[High oncogenic risk human papillomavirus and urinary bladder cancer].

Science.gov (United States)

Loran, O B; Sinyakova, L A; Gundorova, L V; Kosov, V A; Kosova, I V; Pogodina, I E; Kolbasov, D N

2017-07-01

To determine the role of human papillomavirus (HPV) of high oncogenic risk in the development of urinary bladder cancer. 100 patients (72 men and 28 women) aged 38 to 90 years (mean age 65+/-10 years) diagnosed with bladder cancer were examined and underwent treatment. Clinical assessment was complemented by enzyme-linked immunosorbent assays for the presence of antiviral antibodies to herpes simplex virus (HSV) type 1 and type 2, cytomegalovirus (CMV), Epstein-Barr virus (EBV), urethra scraping for detecting high oncogenic risk HPV. Tumor tissue was sampled for PCR virus detection. Semi-quantitative analysis was used to evaluate the components of lymphocyte-plasmocyte and leukocyte infiltrates and cytopathic changes in tumor tissue. There were positive correlations between cytopathic cell changes (koylocytosis and intranuclear inclusions, as manifestations of HPV) and the level of antiviral antibodies, the presence of viruses in the tumor, as well as with the components of the lymphoid-plasmocyte infiltrate. Negative correlations were found between the presence of papillomatosis and the above changes. Human papillomavirus is believed to be a trigger for the initiation of a tumor in young patients with a latent infection (CMV and EBV, HSV, HPV). Cytopathic changes (kylocytosis and intranuclear inclusions) were associated with the activity and morphological features of herpes-viral infections. Their degree varied depending on the stage of the process, but not on the anaplasia degree. Papillomatosis is associated with a more favorable course of the tumor process.

The human T-cell leukemia virus type-1 p30II protein activates p53 and induces the TIGAR and suppresses oncogene-induced oxidative stress during viral carcinogenesis.

Science.gov (United States)

Romeo, Megan; Hutchison, Tetiana; Malu, Aditi; White, Averi; Kim, Janice; Gardner, Rachel; Smith, Katie; Nelson, Katherine; Bergeson, Rachel; McKee, Ryan; Harrod, Carolyn; Ratner, Lee; Lüscher, Bernhard; Martinez, Ernest; Harrod, Robert

2018-05-01

In normal cells, aberrant oncogene expression leads to the accumulation of cytotoxic metabolites, including reactive oxygen species (ROS), which can cause oxidative DNA-damage and apoptosis as an intrinsic barrier against neoplastic disease. The c-Myc oncoprotein is overexpressed in many lymphoid cancers due to c-myc gene amplification and/or 8q24 chromosomal translocations. Intriguingly, p53 is a downstream target of c-Myc and hematological malignancies, such as adult T-cell leukemia/lymphoma (ATL), frequently contain wildtype p53 and c-Myc overexpression. We therefore hypothesized that p53-regulated pro-survival signals may thwart the cell's metabolic anticancer defenses to support oncogene-activation in lymphoid cancers. Here we show that the Tp53-induced glycolysis and apoptosis regulator (TIGAR) promotes c-myc oncogene-activation by the human T-cell leukemia virus type-1 (HTLV-1) latency-maintenance factor p30 II , associated with c-Myc deregulation in ATL clinical isolates. TIGAR prevents the intracellular accumulation of c-Myc-induced ROS and inhibits oncogene-induced cellular senescence in ATL, acute lymphoblastic leukemia, and multiple myeloma cells with elevated c-Myc expression. Our results allude to a pivotal role for p53-regulated antioxidant signals as mediators of c-Myc oncogenic functions in viral and non-viral lymphoid tumors. Copyright © 2018 Elsevier Inc. All rights reserved.

Oncogene-induced progression of preneoplastic rat tracheal epithelial cells to neoplasia

International Nuclear Information System (INIS)

Thomassen, D.G.; Kelly, G.

1988-01-01

N-methyl-N'-nitro-N-nitrosoguanidine (MNNG) induced preneoplastic variants of rat tracheal epithelial (RTE) cells can be neo plastically transformed following transfection with oncogenic DNA. Variants differ with respect to the oncogenes required for neoplastic conversion. Polyma virus DNA transformed each of four variants neo plastically, whereas viral ras DNA only transformed two of four variants. These data demonstrate that preneoplastic variants of RTE cells differ with respect to the changes needed for conversion to neoplastic cells and that the variants tested are either at different stages or on different pathways of progression to neoplasia. (author)

Critical role of the virus-encoded microRNA-155 ortholog in the induction of Marek's disease lymphomas.

Directory of Open Access Journals (Sweden)

Yuguang Zhao

2011-02-01

Full Text Available Notwithstanding the well-characterised roles of a number of oncogenes in neoplastic transformation, microRNAs (miRNAs are increasingly implicated in several human cancers. Discovery of miRNAs in several oncogenic herpesviruses such as KSHV has further highlighted the potential of virus-encoded miRNAs to contribute to their oncogenic capabilities. Nevertheless, despite the identification of several possible cancer-related genes as their targets, the direct in vivo role of virus-encoded miRNAs in neoplastic diseases such as those induced by KSHV is difficult to demonstrate in the absence of suitable models. However, excellent natural disease models of rapid-onset Marek's disease (MD lymphomas in chickens allow examination of the oncogenic potential of virus-encoded miRNAs. Using viruses modified by reverse genetics of the infectious BAC clone of the oncogenic RB-1B strain of MDV, we show that the deletion of the six-miRNA cluster 1 from the viral genome abolished the oncogenicity of the virus. This loss of oncogenicity appeared to be primarily due to the single miRNA within the cluster, miR-M4, the ortholog of cellular miR-155, since its deletion or a 2-nucleotide mutation within its seed region was sufficient to inhibit the induction of lymphomas. The definitive role of this miR-155 ortholog in oncogenicity was further confirmed by the rescue of oncogenic phenotype by revertant viruses that expressed either the miR-M4 or the cellular homolog gga-miR-155. This is the first demonstration of the direct in vivo role of a virus-encoded miRNA in inducing tumors in a natural infection model. Furthermore, the use of viruses deleted in miRNAs as effective vaccines against virulent MDV challenge, enables the prospects of generating genetically defined attenuated vaccines.

B lymphoma Moloney murine leukemia virus insertion region 1: An oncogenic mediator in prostate cancer.

Science.gov (United States)

Liu, Qipeng; Li, Qiaqia; Zhu, Sen; Yi, Yang; Cao, Qi

2018-06-01

B lymphoma Moloney murine leukemia virus insertion region 1 (BMI1), a core member of polycomb repressive complex 1 (PRC1), has been intensely investigated in the field of cancer epigenetics for decades. Widely known as a critical regulator in cellular physiology, BMI1 is essential in self-renewal and differentiation in different lineages of stem cells. BMI1 also plays a significant role in cancer etiology for its involvement in pathological progress such as epithelial-mesenchymal transition (EMT) and cancer stem cell maintenance, propagation, and differentiation. Importantly, overexpression of BMI1 is predictive for drug resistance, tumor recurrence, and eventual therapy failure of various cancer subtypes, which renders the pharmacological targeting at BMI1 as a novel and promising therapeutic approach. The study on prostate cancer, a prevalent hormone-related cancer among men, has promoted enormous research advancements in cancer genetics and epigenetics. This review summarizes the role of BMI1 as an oncogenic and epigenetic regulator in tumor initiation, progression, and relapse of prostate cancer.

V-cbl, an oncogene from a dual-recombinant murine retrovirus that induces early B-lineage lymphomas

International Nuclear Information System (INIS)

Langdon, W.Y.; Klinken, S.P.; Hartley, J.W.; Morse, H.C. III; Ruscetti, S.K.

1989-01-01

Cas NS-1 is an acutely transforming murine retrovirus that induces pre-B and pro-B cell lymphomas. Molecular cloning showed it was generated from the ecotropic Cas-Br-M virus by sequential recombinations with endogenous retroviral sequences and a cellular oncogene. The oncogene sequence shows no homology with known oncogenes but some similarity to the yeast transcriptional activator GCN4. A 100-kDa gag-cbl fusion protein, with no detectable kinase activity, is responsible for the cellular transformation. The cellular homologue of v-cbl, present in mouse and human DNA, is expressed in a range of hemopoietic lineages

ARF and ATM/ATR cooperate in p53-mediated apoptosis upon oncogenic stress

International Nuclear Information System (INIS)

Pauklin, Siim; Kristjuhan, Arnold; Maimets, Toivo; Jaks, Viljar

2005-01-01

Induction of apoptosis is pivotal for eliminating cells with damaged DNA or deregulated proliferation. We show that tumor suppressor ARF and ATM/ATR kinase pathways cooperate in the induction of apoptosis in response to elevated expression of c-myc, β-catenin or human papilloma virus E7 oncogenes. Overexpression of oncogenes leads to the formation of phosphorylated H2AX foci, induction of Rad51 protein levels and ATM/ATR-dependent phosphorylation of p53. Inhibition of ATM/ATR kinases abolishes both induction of Rad51 and phosphorylation of p53, and remarkably reduces the level of apoptosis induced by co-expression of oncogenes and ARF. However, the induction of apoptosis is downregulated in p53-/- cells and does not depend on activities of ATM/ATR kinases, indicating that efficient induction of apoptosis by oncogene activation depends on coordinated action of ARF and ATM/ATR pathways in the regulation of p53

Oncogenicity by adenovirus is not determined by the transforming region only

NARCIS (Netherlands)

Bernards, R.A.; Leeuw, M.G.W. de; Vaessen, M.J.; Houweling, A.; Eb, A.J. van der

1984-01-01

We have constructed a nondefective recombinant virus between the nononcogenic adenovirus 5 (Ad5) and the highly oncogenic Ad12. The recombinant genome consists essentially of Ad5 sequences, with the exception of the transforming early region 1 (E1) which is derived from Ad12. HeLa cells infected

Oncogenic Viral Prevalence in Invasive Vulvar Cancer Specimens from HIV Positive and Negative Women in Botswana

Science.gov (United States)

Tesfalul, Martha; Simbiri, Kenneth; Wheat, Chikoti M.; Motsepe, Didintle; Goldbach, Hayley; Armstrong, Kathleen; Hudson, Kathryn; Kayembe, Mukendi K.; Robertson, Erle; Kovarik, Carrie

2014-01-01

Objective The primary aim of this study is to describe the prevalence of select oncogenic viruses within vulvar squamous cell carcinoma (VSCC) and their association with Human Immunodeficiency Virus (HIV) status in women in Botswana, where the national HIV prevalence is the third highest in the world. Methods/materials A cross-sectional study of biopsy-confirmed VSCC specimens and corresponding clinical data was conducted in Gaborone, Botswana. Polymerase Chain Reaction (PCR) and Immunohistochemistry (IHC) viral testing were done for Epstein-Barr Virus (EBV), Human Papilloma Virus (HPV) strains, and Kaposi's Sarcoma Herpesvirus (KSHV), and PCR viral testing alone was done for John Cunningham Virus (JCV). Results HPV prevalence by PCR was 100% (39/39 35/35) among tested samples. HPV16 was the most prevalent HPV strain (82.9% by PCR, 94.7% by either PCR or IHC). KSHV prevalence by PCR had a significant association with HIV status (p = 0.013), but not by IHC (p = 0.650). Conclusions The high burden of HPV, specifically HPV16, in VSCC in Botswana suggests a distinct HPV profile that differs from other studied populations, which provides increased motivation for HPV vaccination efforts. Oncogenic viruses KSHV and EBV were also more prevalent in our study population though their potential role in VSCC pathology is unclear. PMID:24651632

Progression from productive infection to integration and oncogenic transformation in human papillomavirus type 59-immortalized foreskin keratinocytes.

Science.gov (United States)

Spartz, Helena; Lehr, Elizabeth; Zhang, Benyue; Roman, Ann; Brown, Darron R

2005-05-25

Studies of changes in the virus and host cell upon progression from human papillomavirus (HPV) episomal infection to integration are critical to understanding HPV-related malignant transformation. However, there exist only a few in vitro models of both productive HPV infection and neoplastic progression on the same host background. We recently described a unique foreskin keratinocyte cell line (ERIN 59) that contains HPV 59 (a close relative of HPV 18). Early passages of ERIN 59 cells (passages 9-13) contained approximately 50 copies of episomes/cell, were feeder cell-dependent, and could be induced to differentiate and produce infectious virus in a simple culture system. We now report that late passage cells (passages greater than 50) were morphologically different from early passage cells, were feeder cell independent, and did not differentiate or produce virus. These late passage cells contained HPV in an integrated form. An integration-derived oncogene transcript was expressed in late passage cells. The E2 open reading frame was interrupted in this transcript at nucleotide 3351. Despite a lower viral genome copy number in late passage ERIN 59 cells, expression of E6/E7 oncogene transcripts was similar to early passage cells. We conclude that ERIN 59 cells are a valuable cell line representing a model of progression from HPV 59 episomal infection and virus production to HPV 59 integration and associated oncogenic transformation on the same host background.

Epstein-Barr virus-associated lymphomas.

Science.gov (United States)

Shannon-Lowe, Claire; Rickinson, Alan B; Bell, Andrew I

2017-10-19

Epstein-Barr virus (EBV), originally discovered through its association with Burkitt lymphoma, is now aetiologically linked to a remarkably wide range of lymphoproliferative lesions and malignant lymphomas of B-, T- and NK-cell origin. Some occur as rare accidents of virus persistence in the B lymphoid system, while others arise as a result of viral entry into unnatural target cells. The early finding that EBV is a potent B-cell growth transforming agent hinted at a simple oncogenic mechanism by which this virus could promote lymphomagenesis. In reality, the pathogenesis of EBV-associated lymphomas involves a complex interplay between different patterns of viral gene expression and cellular genetic changes. Here we review recent developments in our understanding of EBV-associated lymphomagenesis in both the immunocompetent and immunocompromised host.This article is part of the themed issue 'Human oncogenic viruses'. © 2017 The Authors.

Determination of the transforming activities of adenovirus oncogenes.

Science.gov (United States)

Speiseder, Thomas; Nevels, Michael; Dobner, Thomas

2014-01-01

The last 50 years of molecular biological investigations into human adenoviruses (Ads) have contributed enormously to our understanding of the basic principles of normal and malignant cell growth. Much of this knowledge stems from analyses of the Ad productive infection cycle in permissive host cells. Also, initial observations concerning the transforming potential of human Ads subsequently revealed decisive insights into the molecular mechanisms of the origins of cancer and established Ads as a model system for explaining virus-mediated transformation processes. Today it is well established that cell transformation by human Ads is a multistep process involving several gene products encoded in early transcription units 1A (E1A) and 1B (E1B). Moreover, a large body of evidence now indicates that alternative or additional mechanisms are engaged in Ad-mediated oncogenic transformation involving gene products encoded in early region 4 (E4) as well as epigenetic changes resulting from viral DNA integration. In particular, studies on the transforming potential of several E4 gene products have now revealed new pathways that point to novel general mechanisms of virus-mediated oncogenesis. In this chapter we describe in vitro and in vivo assays to determine the transforming and oncogenic activities of the E1A, E1B, and E4 oncoproteins in primary baby rat kidney cells, human amniotic fluid cells and athymic nude mice.

Oncogenic human papilloma virus and cervical pre-cancerous lesions in brothel-based sex workers in India

Directory of Open Access Journals (Sweden)

Kamalesh Sarkar

 = 9, those with two to three clients had a prevalence of 30% (n = 34 and those with one or less clients had a prevalence of 10% (n = 9 (statistically significant differences, P = 0.00003. Multivariate analysis showed a statistical association only with a duration of sex work of ≤1 year [odds ratio (OR = 3.3; 95% confidence interval (CI 1.4–7.6] and daily income of Rupees (Rp ≥101 (OR = 2.5; 95% CI 1.3–5. Regarding pre-cancerous lesions, 2 of 229 sex workers showed the presence of a low-grade squamous intraepithelial lesion along with high-risk HPV. Thus, 1% of the studied population suffer from a pre-cancerous lesion caused by high-risk HPV. This study concludes that young sex workers are particularly vulnerable to high-risk HPV, similar to human immunodeficiency virus (HIV. The observation of older sex workers relatively free from HPV supports the view of acquired immunity against HPV, which needs to be studied in-depth further. There is a need for a suitable community-based intervention programme targeted towards sex workers, with special reference to younger sex workers, for control and prevention of HPV and cervical cancer. Vaccination against HPV for newly entrant sex workers may be an important component for a successful intervention programme. Keywords: Human papillomavirus, Oncogenic HPV, Sex workers, India, Risk factors, Cervicitis, Cervical pre-cancerous lesion, STI

Coinfection with Epstein–Barr Virus (EBV), Human Papilloma Virus (HPV) and Polyoma BK Virus (BKPyV) in Laryngeal, Oropharyngeal and Oral Cavity Cancer

OpenAIRE

Drop, Bartłomiej; Strycharz-Dudziak, Małgorzata; Kliszczewska, Ewa; Polz-Dacewicz, Małgorzata

2017-01-01

Most research providing evidence for the role of oncogenic viruses in head and neck squamous cell carcinoma (SCC) development is focused on one type of virus without analyzing possible interactions between two or more types of viruses. The aim of this study was to analyse the prevalence of co-infection with human papillomavirus (HPV), Epstein–Barr virus (EBV) and polyoma BK virus (BKPyV) in oral, oropharyngeal and laryngeal squamous cell carcinomas in Polish patients. The correlations between...

A novel monoclonal antibody for detection of galectin-9 in tissue sections: application to human tissues infected by oncogenic viruses

Directory of Open Access Journals (Sweden)

Barjon Clément

2012-07-01

Full Text Available Abstract Background Galectin-9 is a mammalian lectin which possesses immunosuppressive properties. Excessive production of galectin-9 has been reported in two types of human virus-associated diseases chronic hepatitis C and nasopharyngeal carcinoma associated to the Epstein-Barr virus. The objective of this study was to produce new monoclonal antibodies targeting galectin-9 in order to improve its detection in clinical samples, especially on tissue sections analysed by immunohistochemistry. Methods Hybridomas were produced through immunization of mice with the recombinant c-terminus part of galectin-9 (residues 191 to 355 of the long isoform and semi-solid fusion of spleen cells with Sp2/0 cells. Monoclonal antibodies were characterized using ELISA, epitope mapping, western blot and immunohistochemistry. Results We selected seven hybridomas producing antibodies reacting with our recombinant c-terminus galectin-9 in ELISA. Five of them reacted with the epitope “TPAIPPMMYPHPA” (common to all isoforms, residues 210 to 222 of the long isoform and stained all three isoforms of galectin-9 analysed by western blot. One of them, 1G3,demonstrated very good sensitivity and specificity when used for immunohistochemistry. Using 1G3, we could confirm the intense and constant expression of galectin-9 by Epstein-Barr virus positive malignant cells from nasopharyngeal carcinomas. In most samples, specific staining was detected in both cytoplasm and nuclei. Galectin-9 was also detected in liver biopsies from patients infected by the human hepatitis C or B viruses with expression not only in inflammatory leucocytes and Kupffer cells, but also in hepatocytes. In contrast, galectin-9 was virtually absent in non-infected liver specimens. Conclusion The 1G3 monoclonal antibody will be a powerful tool to assess galectin-9 expression and distribution especially in diseases related to oncogenic viruses.

Ras oncogenes in oral cancer: the past 20 years.

Science.gov (United States)

Murugan, Avaniyapuram Kannan; Munirajan, Arasambattu Kannan; Tsuchida, Nobuo

2012-05-01

Oral squamous cell carcinoma (OSCC) of head and neck is associated with high morbidity and mortality in both Western and Asian countries. Several risk factors for the development of oral cancer are very well established, including tobacco chewing, betel quid, smoking, alcohol drinking and human papilloma virus (HPV) infection. Apart from these risk factors, many genetic factors such as oncogenes, tumor suppressor genes and regulatory genes are identified to involve in oral carcinogenesis with these risk factors dependent and independent manner. Ras is one of the most frequently genetically deregulated oncogene in oral cancer. In this review, we analyze the past 22years of literature on genetic alterations such as mutations and amplifications of the isoforms of the ras oncogene in oral cancer. Further, we addressed the isoform-specific role of the ras in oral carcinogenesis. We also discussed how targeting the Akt and MEK, downstream effectors of the PI3K/Akt and MAPK pathways, respectively, would probably pave the possible molecular therapeutic target for the ras driven tumorigenesis in oral cancer. Analysis of these ras isoforms may critically enlighten specific role of a particular ras isoform in oral carcinogenesis, enhance prognosis and pave the way for isoform-specific molecular targeted therapy in OSCC. Copyright © 2011 Elsevier Ltd. All rights reserved.

Viral Causes of Lymphoma: The History of Epstein-Barr Virus and Human T-Lymphotropic Virus 1.

Science.gov (United States)

Esau, Daniel

2017-01-01

In 1964, Epstein, Barr, and Achong published a report outlining their discovery of viral particles in lymphoblasts isolated from a patient with Burkitt lymphoma. The Epstein-Barr virus (EBV) was the first human cancer virus to be described, and its discovery paved the way for further investigations into the oncogenic potential of viruses. In the decades following the discovery of EBV, multinational research efforts led to the discovery of further viral causes of various human cancers. Lymphomas are perhaps the cancer type that is most closely associated with oncogenic viruses: infection with EBV, human T-lymphotropic virus 1 (HTLV-1), human immunodeficiency virus (HIV), Kaposi sarcoma-associated herpesvirus/human herpesvirus 8, and hepatitis C virus have all been associated with lymphomagenesis. Lymphomas have also played an important role in the history of oncoviruses, as both the first human oncovirus (EBV) and the first human retrovirus (HTLV-1) were discovered through isolates taken from patients with unique lymphoma syndromes. The history of the discovery of these 2 key oncoviruses is presented here, and their impact on further medical research, using the specific example of HIV research, is briefly discussed.

Viral Causes of Lymphoma: The History of Epstein-Barr Virus and Human T-Lymphotropic Virus 1

Directory of Open Access Journals (Sweden)

Daniel Esau

2017-09-01

Full Text Available In 1964, Epstein, Barr, and Achong published a report outlining their discovery of viral particles in lymphoblasts isolated from a patient with Burkitt lymphoma. The Epstein-Barr virus (EBV was the first human cancer virus to be described, and its discovery paved the way for further investigations into the oncogenic potential of viruses. In the decades following the discovery of EBV, multinational research efforts led to the discovery of further viral causes of various human cancers. Lymphomas are perhaps the cancer type that is most closely associated with oncogenic viruses: infection with EBV, human T-lymphotropic virus 1 (HTLV-1, human immunodeficiency virus (HIV, Kaposi sarcoma-associated herpesvirus/human herpesvirus 8, and hepatitis C virus have all been associated with lymphomagenesis. Lymphomas have also played an important role in the history of oncoviruses, as both the first human oncovirus (EBV and the first human retrovirus (HTLV-1 were discovered through isolates taken from patients with unique lymphoma syndromes. The history of the discovery of these 2 key oncoviruses is presented here, and their impact on further medical research, using the specific example of HIV research, is briefly discussed.

Human Papilloma Virus and oral cancer: Narrative review of the literature.

OpenAIRE

Alejandra Fernández; Maureen Marshall; Alfredo Esguep

2014-01-01

ABSTRACT The Human Papilloma Virus (HPV) infection is now more common sexually transmitted diseases, with an incidence of 5.5 million worldwide, with 85% of the carrier of this virus adult population. Their oncogenic potential and increased oral lesions associated with oral HPV infection have led us to make a narrative of the literature on the role of HPV in oral cancer, especially types 16 and 18. Here we refer to the possible routes of infection, oncogenic mechanisms, both benign and potent...

The inhibitory NKR-P1B:Clr-b recognition axis facilitates detection of oncogenic transformation and cancer immunosurveillance

DEFF Research Database (Denmark)

Tanaka, M; Fine, Jason; Kirkham, Christina

2018-01-01

Natural killer (NK) cells express receptors specific for MHC class I (MHC-I) molecules involved in "missing-self" recognition of cancer and virus-infected cells. Here we elucidate the role of MHC-I-independent NKR-P1B:Clr-b interactions in the detection of oncogenic transformation by NK cells. Ras......-b protein, in turn promoting missing-self recognition via the NKR-P1B inhibitory receptor. Both Ras- and c-Myc-mediated Clr-b loss selectively augmented cytotoxicity of oncogene-transformed leukemia cells by NKR-P1B+ NK cells in vitro and enhanced rejection by WT mice in vivo. Interestingly, genetic...

Amino-terminal domain of the v-fms oncogene product includes a functional signal peptide that directs synthesis of a transforming glycoprotein in the absence of feline leukemia virus gag sequences

International Nuclear Information System (INIS)

Wheeler, E.F.; Roussel, M.F.; Hampe, A.; Walker, M.H.; Fried, V.A.; Look, A.T.; Rettenmier, C.W.; Sherr, C.J.

1986-01-01

The nucleotide sequence of a 5' segment of the human genomic c-fms proto-oncogene suggested that recombination between feline leukemia virus and feline c-fms sequences might have occurred in a region encoding the 5' untranslated portion of c-fms mRNA. The polyprotein precursor gP180/sup gag-fms/ encoded by the McDonough strain of feline sarcoma virus was therefore predicted to contain 34 v-fms-coded amino acids derived from sequences of the c-fms gene that are not ordinarily translated from the proto-oncogene mRNA. The (gP180/sup gag-fms/) polyprotein was cotranslationally cleaved near the gag-fms junction to remove its gag gene-coded portion. Determination of the amino-terminal sequence of the resulting v-fms-coded glycoprotein, gp120/sup v-fms/, showed that the site of proteolysis corresponded to a predicted signal peptidase cleavage site within the c-fms gene product. Together, these analyses suggested that the linked gag sequences may not be necessary for expression of a biologically active v-fms gene product. The gag-fms sequences of feline sarcoma virus strain McDonough and the v-fms sequences alone were inserted into a murine retroviral vector containing a neomycin resistance gene. The authors conclude that a cryptic hydrophobic signal peptide sequence in v-fms was unmasked by gag deletion, thereby allowing the correct orientation and transport of the v-fms was unmasked by gag deletion, thereby allowing the correct orientation and transport of the v-fms gene product within membranous organelles. It seems likely that the proteolytic cleavage of gP180/gag-fms/ is mediated by signal peptidase and that the amino termini of gp140/sup v-fms/ and the c-fms gene product are identical

Amino-terminal domain of the v-fms oncogene product includes a functional signal peptide that directs synthesis of a transforming glycoprotein in the absence of feline leukemia virus gag sequences

Energy Technology Data Exchange (ETDEWEB)

Wheeler, E.F.; Roussel, M.F.; Hampe, A.; Walker, M.H.; Fried, V.A.; Look, A.T.; Rettenmier, C.W.; Sherr, C.J.

1986-08-01

The nucleotide sequence of a 5' segment of the human genomic c-fms proto-oncogene suggested that recombination between feline leukemia virus and feline c-fms sequences might have occurred in a region encoding the 5' untranslated portion of c-fms mRNA. The polyprotein precursor gP180/sup gag-fms/ encoded by the McDonough strain of feline sarcoma virus was therefore predicted to contain 34 v-fms-coded amino acids derived from sequences of the c-fms gene that are not ordinarily translated from the proto-oncogene mRNA. The (gP180/sup gag-fms/) polyprotein was cotranslationally cleaved near the gag-fms junction to remove its gag gene-coded portion. Determination of the amino-terminal sequence of the resulting v-fms-coded glycoprotein, gp120/sup v-fms/, showed that the site of proteolysis corresponded to a predicted signal peptidase cleavage site within the c-fms gene product. Together, these analyses suggested that the linked gag sequences may not be necessary for expression of a biologically active v-fms gene product. The gag-fms sequences of feline sarcoma virus strain McDonough and the v-fms sequences alone were inserted into a murine retroviral vector containing a neomycin resistance gene. The authors conclude that a cryptic hydrophobic signal peptide sequence in v-fms was unmasked by gag deletion, thereby allowing the correct orientation and transport of the v-fms was unmasked by gag deletion, thereby allowing the correct orientation and transport of the v-fms gene product within membranous organelles. It seems likely that the proteolytic cleavage of gP180/gag-fms/ is mediated by signal peptidase and that the amino termini of gp140/sup v-fms/ and the c-fms gene product are identical.

AKT capture by feline leukemia virus.

Science.gov (United States)

Kawamura, Maki; Umehara, Daigo; Odahara, Yuka; Miyake, Ariko; Ngo, Minh Ha; Ohsato, Yoshiharu; Hisasue, Masaharu; Nakaya, Masa-Aki; Watanabe, Shinya; Nishigaki, Kazuo

2017-04-01

Oncogene-containing retroviruses are generated by recombination events between viral and cellular sequences, a phenomenon called "oncogene capture". The captured cellular genes, referred to as "v-onc" genes, then acquire new oncogenic properties. We report a novel feline leukemia virus (FeLV), designated "FeLV-AKT", that has captured feline c-AKT1 in feline lymphoma. FeLV-AKT contains a gag-AKT fusion gene that encodes the myristoylated Gag matrix protein and the kinase domain of feline c-AKT1, but not its pleckstrin homology domain. Therefore, it differs structurally from the v-Akt gene of murine retrovirus AKT8. AKT may be involved in the mechanisms underlying malignant diseases in cats.

Risk factors and distribution of oncogenic strains of human papilloma virus in women presenting for cervical cancer screening in Port Harcourt, Nigeria.

Science.gov (United States)

Kennedy, Nyengidiki Tamunomie; Ikechukwu, Durugbo; Goddy, Bassey

2016-01-01

Human papilloma virus(HPV) accounts for most cases of cervical cancer with high risk HPV(hrHPV) genotypes largely responsible. The objective is to ascertain the distribution of oncogenic strains of human papilloma virus genotypes and predisposing risk factors in women presenting for cervical cancer screening in Nigeria. A cross-sectional study of 80 women who presented for cervical cancer screening. The biodata of the participants, the presence of risk factors to HPV were recorded and hrHPV were identified using PCR technique. The information obtained was processed using the SPSS version 20 software. Results were presented in tables, test of significance and association done using student's t-test and Odds ratio, with P value prevalence of hrHPV of 10%. HrHPV are more in patients with more than one life time sexual partner (OR 1.26,95%CI 0.13-29.99), multiple sexual partners (OR 1.55, 95% CI 0.28-8.70), early coitarche (OR 1.57, 95% CI 0.14-15.00) and previous STI (OR 150, 95%CI 9.53-1979. 62). Four hrHPV genotypes: 16, 18, 31 and 35 were detected. HPV genotype 18 was predominant in Port Harcourt, Nigeria. High risk sexual behaviours are associated with acquisition of hrHPV.

Identifying Breast Cancer Oncogenes

Science.gov (United States)

2011-10-01

cells we observed that it promoted transformation of HMLE cells, suggesting a tumor suppressive role of Merlin in breast cancer (Figure 4B). A...08-1-0767 TITLE: Identifying Breast Cancer Oncogenes PRINCIPAL INVESTIGATOR: Yashaswi Shrestha...Standard Form 298 (Rev. 8-98) Prescribed by ANSI Std. Z39.18 W81XWH-08-1-0767 Identifying Breast Cancer Oncogenes Yashaswi Shrestha Dana-Farber

Oncogenic cancer/testis antigens

DEFF Research Database (Denmark)

Gjerstorff, Morten F; Andersen, Mads H; Ditzel, Henrik J

2015-01-01

Recent developments have set the stage for immunotherapy as a supplement to conventional cancer treatment. Consequently, a significant effort is required to further improve efficacy and specificity, particularly the identification of optimal therapeutic targets for clinical testing. Cancer....../testis antigens are immunogenic, highly cancer-specific, and frequently expressed in various types of cancer, which make them promising candidate targets for cancer immunotherapy, including cancer vaccination and adoptive T-cell transfer with chimeric T-cell receptors. Our current understanding of tumor...... immunology and immune escape suggests that targeting oncogenic antigens may be beneficial, meaning that identification of cancer/testis antigens with oncogenic properties is of high priority. Recent work from our lab and others provide evidence that many cancer/testis antigens, in fact, have oncogenic...

Coinfection with Epstein–Barr Virus (EBV, Human Papilloma Virus (HPV and Polyoma BK Virus (BKPyV in Laryngeal, Oropharyngeal and Oral Cavity Cancer

Directory of Open Access Journals (Sweden)

Bartłomiej Drop

2017-12-01

Full Text Available Most research providing evidence for the role of oncogenic viruses in head and neck squamous cell carcinoma (SCC development is focused on one type of virus without analyzing possible interactions between two or more types of viruses. The aim of this study was to analyse the prevalence of co-infection with human papillomavirus (HPV, Epstein–Barr virus (EBV and polyoma BK virus (BKPyV in oral, oropharyngeal and laryngeal squamous cell carcinomas in Polish patients. The correlations between viral infection, SCC, demographic parameters, evidence of metastases and grading were also investigated. Fresh-frozen tumour tissue samples were collected from 146 patients with laryngeal, oropharyngeal and oral cancer. After DNA extraction, the DNA of the studied viruses was detected using polymerase chain rection (PCR assay. Males (87.7% with a history of smoking (70.6% and alcohol abuse (59.6% prevailed in the studied group. Histological type G2 was recognized in 64.4% cases. The patients were most frequently diagnosed with T2 stage (36.3% and with N1 stage (45.8%. Infection with at least two viruses was detected in 56.2% of patients. In this group, co-infection with HPV/EBV was identified in 34.1% of cases, EBV/BKV in 23.2%, HPV/BKV in 22.0%, and HPV/EBV/BKV in 20.7%. No difference of multiple infection in different locations of cancer was observed. The prevalence of poorly differentiated tumours (G3 was more frequent in co-infection with all three viruses than EBV or BKV alone. A significant correlation was observed between tumour dimensions (T and lymph-node involvement (N in co-infected patients compared to single infection. Further studies are necessary to clarify whether co-infection plays an important role in the initiation and/or progression of oncogenic transformation of oral, oropharyngeal and laryngeal epithelial cells.

Coinfection with Epstein-Barr Virus (EBV), Human Papilloma Virus (HPV) and Polyoma BK Virus (BKPyV) in Laryngeal, Oropharyngeal and Oral Cavity Cancer.

Science.gov (United States)

Drop, Bartłomiej; Strycharz-Dudziak, Małgorzata; Kliszczewska, Ewa; Polz-Dacewicz, Małgorzata

2017-12-19

Most research providing evidence for the role of oncogenic viruses in head and neck squamous cell carcinoma (SCC) development is focused on one type of virus without analyzing possible interactions between two or more types of viruses. The aim of this study was to analyse the prevalence of co-infection with human papillomavirus (HPV), Epstein-Barr virus (EBV) and polyoma BK virus (BKPyV) in oral, oropharyngeal and laryngeal squamous cell carcinomas in Polish patients. The correlations between viral infection, SCC, demographic parameters, evidence of metastases and grading were also investigated. Fresh-frozen tumour tissue samples were collected from 146 patients with laryngeal, oropharyngeal and oral cancer. After DNA extraction, the DNA of the studied viruses was detected using polymerase chain rection (PCR) assay. Males (87.7%) with a history of smoking (70.6%) and alcohol abuse (59.6%) prevailed in the studied group. Histological type G2 was recognized in 64.4% cases. The patients were most frequently diagnosed with T2 stage (36.3%) and with N1 stage (45.8%). Infection with at least two viruses was detected in 56.2% of patients. In this group, co-infection with HPV/EBV was identified in 34.1% of cases, EBV/BKV in 23.2%, HPV/BKV in 22.0%, and HPV/EBV/BKV in 20.7%. No difference of multiple infection in different locations of cancer was observed. The prevalence of poorly differentiated tumours (G3) was more frequent in co-infection with all three viruses than EBV or BKV alone. A significant correlation was observed between tumour dimensions (T) and lymph-node involvement (N) in co-infected patients compared to single infection. Further studies are necessary to clarify whether co-infection plays an important role in the initiation and/or progression of oncogenic transformation of oral, oropharyngeal and laryngeal epithelial cells.

Coinfection with Epstein–Barr Virus (EBV), Human Papilloma Virus (HPV) and Polyoma BK Virus (BKPyV) in Laryngeal, Oropharyngeal and Oral Cavity Cancer

Science.gov (United States)

Drop, Bartłomiej; Strycharz-Dudziak, Małgorzata; Kliszczewska, Ewa; Polz-Dacewicz, Małgorzata

2017-01-01

Most research providing evidence for the role of oncogenic viruses in head and neck squamous cell carcinoma (SCC) development is focused on one type of virus without analyzing possible interactions between two or more types of viruses. The aim of this study was to analyse the prevalence of co-infection with human papillomavirus (HPV), Epstein–Barr virus (EBV) and polyoma BK virus (BKPyV) in oral, oropharyngeal and laryngeal squamous cell carcinomas in Polish patients. The correlations between viral infection, SCC, demographic parameters, evidence of metastases and grading were also investigated. Fresh-frozen tumour tissue samples were collected from 146 patients with laryngeal, oropharyngeal and oral cancer. After DNA extraction, the DNA of the studied viruses was detected using polymerase chain rection (PCR) assay. Males (87.7%) with a history of smoking (70.6%) and alcohol abuse (59.6%) prevailed in the studied group. Histological type G2 was recognized in 64.4% cases. The patients were most frequently diagnosed with T2 stage (36.3%) and with N1 stage (45.8%). Infection with at least two viruses was detected in 56.2% of patients. In this group, co-infection with HPV/EBV was identified in 34.1% of cases, EBV/BKV in 23.2%, HPV/BKV in 22.0%, and HPV/EBV/BKV in 20.7%. No difference of multiple infection in different locations of cancer was observed. The prevalence of poorly differentiated tumours (G3) was more frequent in co-infection with all three viruses than EBV or BKV alone. A significant correlation was observed between tumour dimensions (T) and lymph-node involvement (N) in co-infected patients compared to single infection. Further studies are necessary to clarify whether co-infection plays an important role in the initiation and/or progression of oncogenic transformation of oral, oropharyngeal and laryngeal epithelial cells. PMID:29257122

Role of Virus-Encoded microRNAs in Avian Viral Diseases

Directory of Open Access Journals (Sweden)

Yongxiu Yao

2014-03-01

Full Text Available With total dependence on the host cell, several viruses have adopted strategies to modulate the host cellular environment, including the modulation of microRNA (miRNA pathway through virus-encoded miRNAs. Several avian viruses, mostly herpesviruses, have been shown to encode a number of novel miRNAs. These include the highly oncogenic Marek’s disease virus-1 (26 miRNAs, avirulent Marek’s disease virus-2 (36 miRNAs, herpesvirus of turkeys (28 miRNAs, infectious laryngotracheitis virus (10 miRNAs, duck enteritis virus (33 miRNAs and avian leukosis virus (2 miRNAs. Despite the closer antigenic and phylogenetic relationship among some of the herpesviruses, miRNAs encoded by different viruses showed no sequence conservation, although locations of some of the miRNAs were conserved within the repeat regions of the genomes. However, some of the virus-encoded miRNAs showed significant sequence homology with host miRNAs demonstrating their ability to serve as functional orthologs. For example, mdv1-miR-M4-5p, a functional ortholog of gga-miR-155, is critical for the oncogenicity of Marek’s disease virus. Additionally, we also describe the potential association of the recently described avian leukosis virus subgroup J encoded E (XSR miRNA in the induction of myeloid tumors in certain genetically-distinct chicken lines. In this review, we describe the advances in our understanding on the role of virus-encoded miRNAs in avian diseases.

Effect of ionizing radiation on the biological activity of activated oncogenes and dormant proto-oncogenes

International Nuclear Information System (INIS)

Angenent, G.C.; Berg, K.J. van den.

1984-01-01

The authors have studied the effect of ionizing radiation on the cloned human activated Ha-ras oncogene, on the Ha-ras gene in integrated form and on the dormant proto-oncogene murine c-mos using the NIH/3T3 transfection system. NIH/3T3 cells were transfected with DNA from the plasmid pT24 carrying the cloned Ha-ras oncogene of the T24 bladder carcinoma cell line. Various individual foci which developed were injected into nude mice. DNA was isolated from tumours, digested with the restriction enzyme Bam HI, electrophoresed on agarose and blotted onto nitrocellulose filter according to Southern. Hybridization with a pT24 probe showed that all the primary foci of transformed cells contained various fragments of the pT24 plasmid indicating that fibroblast transformation had been induced by introduction of the Ha-ras oncogene. (Auth.)

Oncogenic impact of human papilloma virus in head and neck cancer.

LENUS (Irish Health Repository)

Heffernan, C B

2012-02-01

There is considerable debate within the literature about the significance of human papilloma virus in head and neck squamous cell carcinoma, and its potential influence on the prevention, diagnosis, grading, treatment and prognosis of these cancers. Cigarette smoking and alcohol consumption have traditionally been cited as the main risk factors for head and neck cancers. However, human papilloma virus, normally associated with cervical and other genital carcinomas, has emerged as a possible key aetiological factor in head and neck squamous cell carcinoma, especially oropharyngeal cancers. These cancers pose a significant financial burden on health resources and are increasing in incidence. The recent introduction of vaccines targeted against human papilloma virus types 16 and 18, to prevent cervical cancer, has highlighted the need for ongoing research into the importance of human papilloma virus in head and neck squamous cell carcinoma.

Constitutive activation of a variant of the env-mpl oncogene product by disulfide-linked homodimerization.

OpenAIRE

Courtois, G; Bénit, L; Mikaeloff, Y; Pauchard, M; Charon, M; Varlet, P; Gisselbrecht, S

1995-01-01

The myeloproliferative leukemia retrovirus (MPLV) has the v-mpl cellular sequences transduced in frame with the deleted and rearranged Friend murine leukemia virus env gene. The resulting env-mpl fusion oncogene is responsible for an acute myeloproliferative disorder induced in mice by MPLV. v-mpl is a truncated form of the c-mpl gene which encodes the receptor for thrombopoietin. We investigated the contribution of the Env-Mpl extracellular domain in the constitutive activation of this trunc...

A Role for RNA Viruses in the Pathogenesis of Burkitt's Lymphoma: The Need for Reappraisal

Directory of Open Access Journals (Sweden)

Corry van den Bosch

2012-01-01

Full Text Available Certain infectious agents are associated with lymphomas, but the strength of the association varies geographically, suggesting that local environmental factors make important contributions to lymphomagenesis. Endemic Burkitt’s Lymphoma has well-defined environmental requirements making it particularly suitable for research into local environmental factors. The Epstein-Barr virus and holoendemic Malaria are recognized as important cofactors in endemic Burkitt’s Lymphoma and their contributions are discussed. Additionally, infection with Chikungunya Fever, a potentially oncogenic arbovirus, was associated with the onset of endemic Burkitt’s Lymphoma in one study and also with space-time case clusters of the lymphoma. Chikungunya Virus has several characteristics typical of oncogenic viruses. The Flavivirus, Hepatitis C, a Class 1 Human Carcinogen, closely related to the arboviruses, Yellow Fever, and Dengue, is also more distantly related to Chikungunya Virus. The mechanisms of oncogenesis believed to operate in Hepatitis C lymphomagenesis are discussed, as is their potential applicability to Chikungunya Virus.

Macrophage colony-stimulating factor, CSF-1, and its proto-oncogene-encoded receptor

International Nuclear Information System (INIS)

Sherr, C.J.; Rettenmier, C.W.; Roussel, M.F.

1988-01-01

The macrophage colony-stimulating factor, CSF-1, or M-CSF, is one of a family of hematopoietic growth factors that stimulates the proliferation of monocytes, macrophages, and their committed bone marrow progenitors. Unlike pluripotent hemopoietins such as granulocyte-macrophage colony-stimulating factor (GM-CSF) and interleukin-3 (IL-3 or multi-CSF), which affect the growth of myeloid cells of several different hematopoietic lineages, CSF-1 acts only on cells of the mononuclear phagocyte series to stimulate their growth and enhance their survival. Retroviral transduction of the feline c-fms gene in the Susan McDonough and Hardy Zuckerman-5 (HZ-5) strains of feline sarcoma virus (FeSV) led to genetic alterations that endowed the recombined viral oncogene (v-fms) with the ability to transform cells in culture morphologically and to induce firbrosarcomas and hematopoietic neoplasms in susceptible animals. The v-fms oncogene product differs from the normal CSF-1 receptor in certain of its cardinal biochemical properties, most notably in exhibiting constitutively high basal levels of tyrosine kinase activity in the absence of its ligand. Comparative studies of the c-fms and v-fms genes coupled with analyses of engineered mutants and receptor chimeras have begun to pinpoint pertinent genetic alterations in the normal receptor gene that unmask its latent oncogenic potential. In addition, the availability of biologically active c-fms, v-fms, and CSF-1 cDNAs has allowed these genes to be mobilized and expressed in naive cells, thereby facilitating assays for receptor coupling with downstream components of the mitogenic pathway in diverse cell types

Gene activated by growth factors is related to the oncogene v-jun

International Nuclear Information System (INIS)

Ryder, K.; Lau, L.F.; Nathans, D.

1988-01-01

The authors have recently identified by cDNA cloning a set of genes that are rapidly activated in cultured mouse cells by protein growth factors. Here they report that the nucleotide sequence of a cDNA (clone 465) derived from one of these immediate early genes (hereafter called jun-B) encodes a protein homologous to that encoded by the avian sarcoma virus 17 oncogene v-jun. Homology between the jun-B and v-jun proteins is in two regions: one near the N terminus and the other at the C terminus. The latter sequence was shown to have regions of sequence similarity to the DNA-binding domain of the yeast transcriptional regulatory protein GCN4 and to the oncogenic protein fos. Southern blots of human, mouse, and chicken DNA demonstrate that jun-B and c-jun are different genes and that there may be other vertebrate genes related to jun-B and c-jun. These findings suggest that there is a jun family of genes encoding related transcriptional regulatory proteins. The jun-B protein, and perhaps other members of the jun family, may play a role in regulating the genomic response to growth factors

Sequence variation of functional HTLV-II tax alleles among isolates from an endemic population: lack of evidence for oncogenic determinant in tax.

Science.gov (United States)

Hjelle, B; Chaney, R

1992-02-01

Human T-cell leukemia-lymphoma virus type II (HTLV-II) has been isolated from patients with hairy cell leukemia (HCL). We previously described a population with longstanding endemic HTLV-II infection, and showed that there is no increased risk for HCL in the affected groups. We thus have direct evidence that the endemic form(s) of HTLV-II cause HCL infrequently, if at all. By comparison, there is reason to suspect that the viruses isolated from patients with HCL had an etiologic role in the disease in those patients. One way to reconcile these conflicting observations is to consider that isolates of HTLV-II might differ in oncogenic potential. To determine whether the structure of the putative oncogenic determinant of HTLV-II, tax2, might differ in the new isolates compared to the tax of the prototype HCL isolate, MO, four new functional tax cDNAs were cloned from new isolates. Sequence analysis showed only minor (0.9-2.0%) amino acid variation compared to the published sequence of MO tax2. Some codons were consistently different from published sequences of the MO virus, but in most cases, such variations were also found in each of two tax2 clones we isolated from the MO T-cell line. These variations rendered the new clones more similar to the tax1 of the pathogenic virus HTLV-I. Thus we find no evidence that pathologic determinants of HTLV-II can be assigned to the tax gene.

[THE COMPARATIVE ANALYSIS OF RESULTS OF DETECTION OF CARCINOGENIC TYPES OF HUMAN PAPILLOMA VIRUS BY QUALITATIVE AND QUANTITATIVE TESTS].

Science.gov (United States)

Kuzmenko, E T; Labigina, A V; Leshenko, O Ya; Rusanov, D N; Kuzmenko, V V; Fedko, L P; Pak, I P

2015-05-01

The analysis of results of screening (n = 3208; sexually active citizen aged from 18 to 59 years) was carried out to detect oncogene types of human papilloma virus in using qualitative (1150 females and 720 males) and quantitative (polymerase chain reaction in real-time (843 females and 115 males) techniques. The human papilloma virus of high oncogene type was detected in 65% and 68.4% of females and in 48.6% and 53% of males correspondingly. Among 12 types of human papilloma virus the most frequently diagnosed was human papilloma virus 16 independently of gender of examined and technique of analysis. In females, under application of qualitative tests rate of human papilloma virus 16 made up to 18.3% (n = 280) and under application of quantitative tests Rte of human papilloma virus made up to 14.9% (n = 126; p ≤ 0.05). Under examination of males using qualitative tests rate of human papilloma virus 16 made up to 8.3% (n = 60) and under application of qualitative tests made up to 12.2% (n = 14; p ≥ 0.05). Under application of qualitative tests rate of detection on the rest ofoncogene types of human papilloma virus varied in females from 3.4% to 8.4% and in males from 1.8% to 5.9%. Under application of qualitative tests to females rate of human papilloma virus with high viral load made up to 68.4%, with medium viral load - 2.85% (n = 24) and with low viral load -0.24% (n = 2). Under application of quantitative tests in males rate of detection of types of human papilloma virus made up to 53% and at that in all high viral load was established. In females, the most of oncogene types of human papilloma virus (except for 31, 39, 59) are detected significantly more often than in males.

Human Papilloma Virus and oral cancer: Narrative review of the literature.

Directory of Open Access Journals (Sweden)

Alejandra Fernández

2014-09-01

Full Text Available The Human Papilloma Virus (HPV infection is now more common sexually transmitted diseases, with an incidence of 5.5 million worldwide, with 85% of the carrier of this virus adult population. Their oncogenic potential and increased oral lesions associated with oral HPV infection have led us to make a narrative of the literature on the role of HPV in oral cancer, especially types 16 and 18. Here we refer to the possible routes of infection, oncogenic mechanisms, both benign and potentially malignant oral lesions associated with the infection, different methods used for detection, prediction and prevention of infection. We stress the importance of the role of the dentist to identify individuals considered high risk and ease of performing detection in the oral cavity, through a quick and easy method as exfoliative cytology.

Oncogenes and radiosensitivity: in vitro studies. Potential impact in radiotherapy

International Nuclear Information System (INIS)

Alapetite, C.; Moustacchi, E.; Cosset, J.M.

1992-01-01

It is of interest to address the question of whether or not activated oncogenes can influence tumorigenic cell response to radiations. Malignant transformation through transfection of oncogenes offers a possibility for in vitro comparison of transformed cells and parental cells. Murin cellular system analysis suggests an acquisition of radioresistance through some oncogenes transfection. In human cells, only a limited number of oncogenes (ras and myc) has been studied so far. To date, no crucial influence could be demonstrated. The extension of the analysis to other oncogenes and suppressor genes could potentially be helpful for the choice and the modalities of cancer treatment

Oncogenic activation of v-kit involves deletion of a putative tyrosine-substrate interaction site.

Science.gov (United States)

Herbst, R; Munemitsu, S; Ullrich, A

1995-01-19

The transforming gene of the Hardy-Zuckerman-4 strain of feline sarcoma virus, v-kit, arose by transduction of the cellular c-kit gene, which encodes the receptor tyrosine kinase (RTK) p145c-kit. To gain insight into the molecular basis of the v-kit transforming potential, we characterized the feline c-kit by cDNA cloning. Comparison of the feline v-kit and c-kit sequences revealed, in addition to deletions of the extracellular and transmembrane domains, three additional mutations in the v-kit oncogene product: deletion of tyrosine-569 and valine-570, the exchange of aspartate at position 761 to glycine, and replacement of the C-terminal 50 amino acids by five unrelated residues. Examinations of individual v-kit mutations in the context of chimeric receptors yielded inhibitory effects for some mutants on both autophosphorylation and substrate phosphorylation functions. In contrast, deletion of tyrosine-569 and valine-570 significantly enhanced transforming and mitogenic activities of p145c-kit, while the other mutations had no significant effects. Conservation in subclass III RTKs and the identification of the corresponding residue in beta PDGF-R, Y579, as a binding site for src family tyrosine kinases suggests an important role for Y568 in kit signal regulation and the definition of its oncogenic potential. Repositioning of Y571 by an inframe two codon deletion may be the crucial alteration resulting in enhancement of v-kit oncogenic activity.

Attempts on producing lymphoid cell line from Penaeus monodon by induction with SV40-T and 12S EIA oncogenes.

Science.gov (United States)

Puthumana, Jayesh; Prabhakaran, Priyaja; Philip, Rosamma; Singh, I S Bright

2015-12-01

In an attempt of in vitro transformation, transfection mediated expression of Simian virus-40 (T) antigen (SV40-T) and transduction mediated expression of Adenovirus type 12 early region 1A (12S E1A) oncogene were performed in Penaeus monodon lymphoid cells. pSV3-neo vector encoding SV40-T oncogene and a recombinant baculovirus BacP2-12S E1A-GFP encoding 12S E1A oncogene under the control of hybrid promoters were used. Electroporation and lipofection mediated transformation of SV40-T in lymphoid cells confirmed the transgene expression by phenotypic variation and the expression of GFP in co-transfection experiment. The cells transfected by lipofection (≥ 5%) survived for 14 days with lower toxicity (30%), whilst on electroporation, most of the cells succumbed to death (60%) and survived cells lived up to 7 days. Transduction efficiency in primary lymphoid cells was more than 80% within 14 days of post-transduction, however, an incubation period of 7 days post-transduction was observed without detectable expression of 12S E1A. High level of oncogenic 12S E1A expression were observed after 14 day post-transduction and the proliferating cells survived for more than 90 days with GFP expression, however, without in vitro transformation and immortalization. The study put forth the requirement of transduction mediated 'specific' oncogene expression along with telomerase activation and epigenetic induction for the immortalization and establishment of shrimp cell line. Copyright © 2015. Published by Elsevier Ltd.

Role of the ubiquitin system and tumor viruses in AIDS-related cancer

Directory of Open Access Journals (Sweden)

Pagano Joseph S

2007-11-01

Full Text Available Abstract Tumor viruses are linked to approximately 20% of human malignancies worldwide. This review focuses on examples of human oncogenic viruses that manipulate the ubiquitin system in a subset of viral malignancies; those associated with AIDS. The viruses include Kaposi's sarcoma herpesvirus, Epstein-Barr virus and human papilloma virus, which are causally linked to Kaposi's sarcoma, certain B-cell lymphomas and cervical cancer, respectively. We discuss the molecular mechanisms by which these viruses subvert the ubiquitin system and potential viral targets for anti-cancer therapy from the perspective of this system. Publication history: Republished from Current BioData's Targeted Proteins database (TPdb; http://www.targetedproteinsdb.com.

Genome-wide analysis of Epstein-Barr virus identifies variants and genes associated with gastric carcinoma and population structure.

Science.gov (United States)

Yao, Youyuan; Xu, Miao; Liang, Liming; Zhang, Haojiong; Xu, Ruihua; Feng, Qisheng; Feng, Lin; Luo, Bing; Zeng, Yi-Xin

2017-10-01

Epstein-Barr virus is a ubiquitous virus and is associated with several human malignances, including the significant subset of gastric carcinoma, Epstein-Barr virus-associated gastric carcinoma. Some Epstein-Barr virus-associated diseases are uniquely prevalent in populations with different geographic origins. However, the features of the disease and geographically associated Epstein-Barr virus genetic variation as well as the roles that the variation plays in carcinogenesis and evolution remain unclear. Therefore, in this study, we sequenced 95 geographically distinct Epstein-Barr virus isolates from Epstein-Barr virus-associated gastric carcinoma biopsies and saliva of healthy donors to detect variants and genes associated with gastric carcinoma and population structure from a genome-wide spectrum. We demonstrated that Epstein-Barr virus revealed the population structure between North China and South China. In addition, we observed population stratification between Epstein-Barr virus strains from gastric carcinoma and healthy controls, indicating that certain Epstein-Barr virus subtypes are associated with different gastric carcinoma risks. We identified that the BRLF1, BBRF3, and BBLF2/BBLF3 genes had significant associations with gastric carcinoma. LMP1 and BNLF2a genes were strongly geographically associated genes in Epstein-Barr virus. Our study provides insights into the genetic basis of oncogenic Epstein-Barr virus for gastric carcinoma, and the genetic variants associated with gastric carcinoma can serve as biomarkers for oncogenic Epstein-Barr virus.

A Network-Based Model of Oncogenic Collaboration for Prediction of Drug Sensitivity

Directory of Open Access Journals (Sweden)

Ted G Laderas

2015-12-01

Full Text Available Tumorigenesis is a multi-step process, involving the acquisition of multiple oncogenic mutations that transform cells, resulting in systemic dysregulation that enables proliferation, among other cancer hallmarks. High throughput omics techniques are used in precision medicine, allowing identification of these mutations with the goal of identifying treatments that target them. However, the multiplicity of oncogenes required for transformation, known as oncogenic collaboration, makes assigning effective treatments difficult. Motivated by this observation, we propose a new type of oncogenic collaboration where mutations in genes that interact with an oncogene may contribute to its dysregulation, a new genomic feature that we term surrogate oncogenes. By mapping mutations to a protein/protein interaction network, we can determine significance of the observed distribution using permutation-based methods. For a panel of 38 breast cancer cell lines, we identified significant surrogate oncogenes in oncogenes such as BRCA1 and ESR1. In addition, using Random Forest Classifiers, we show that these significant surrogate oncogenes predict drug sensitivity for 74 drugs in the breast cancer cell lines with a mean error rate of 30.9%. Additionally, we show that surrogate oncogenes are predictive of survival in patients. The surrogate oncogene framework incorporates unique or rare mutations on an individual level. Our model has the potential for integrating patient-unique mutations in predicting drug-sensitivity, suggesting a potential new direction in precision medicine, as well as a new approach for drug development. Additionally, we show the prevalence of significant surrogate oncogenes in multiple cancers within the Cancer Genome Atlas, suggesting that surrogate oncogenes may be a useful genomic feature for guiding pancancer analyses and assigning therapies across many tissue types.

Oncogenes E6-E7 de los Papilomavirus Humanos de alto riesgo detectados por PCR en Biopsias de pene incluidas en parafina

Directory of Open Access Journals (Sweden)

I Guerrero

1999-01-01

Full Text Available La alta prevalencia del papilomavirus humano (PVH, referida a nivel mundial, en lesiones genitales de ambos sexos, el rol del varón como reservorio pasivo del virus, y el incremento de la mortalidad por cáncer genital en la mujer en nuestro país, motiva la detección y correlación de los oncogenes de los PVH de alto riesgo con la neoplasia de pene. Informamos de diez casos de biopsias de carcinoma escamoso de pene, incluidos en parafina, los cuales fueron investigados para la presencia de los oncogenes E6-E7 de PVH de alto riesgo, utilizando cebadores tipo específico para los PVH -16 y 18, mediante la reacción en cadena de la polimerasa (PCR. El 40% de los casos mostró un producto de amplificación ADN E6-E7 de los PVH estudiados, correspondiendo el 75% de ellos a detección simple por PVH-18 y el 25% presentó detección mixta ADN E6 - E7 del PVH-16 y 18 simultáneamente. El producto de amplificación fue sometido a comprobación por análisis de restricción específico. La prevalencia obtenida de los oncogenes E6-E7 de los PVH de alto riesgo, usando un método tan sensible como la PCR, apoya el rol de estos virus en el proceso de carcinogénesis de la neoplasia de pene.

Characterization of the env gene and long terminal repeat of molecularly cloned Friend mink cell focus-inducing virus DNA.

OpenAIRE

Adachi, A; Sakai, K; Kitamura, N; Nakanishi, S; Niwa, O; Matsuyama, M; Ishimoto, A

1984-01-01

The highly oncogenic erythroleukemia-inducing Friend mink cell focus-inducing (MCF) virus was molecularly cloned in phage lambda gtWES.lambda B, and the DNA sequences of the env gene and the long terminal repeat were determined. The nucleotide sequences of Friend MCF virus and Friend spleen focus-forming virus were quite homologous, supporting the hypothesis that Friend spleen focus-forming virus might be generated via Friend MCF virus from an ecotropic Friend virus mainly by some deletions. ...

Identification of domains of the v-crk oncogene product sufficient for association with phosphotyrosine-containing proteins.

OpenAIRE

Matsuda, M; Mayer, B J; Hanafusa, H

1991-01-01

The oncogene product of the avian sarcoma virus CT10, P47gag-crk, contains the SH2, SH2', and SH3 domains and binds proteins in a phosphotyrosine (ptyr)-dependent manner. In this study, we have determined the region of P47gag-crk essential for binding to ptyr-containing proteins. Mutant P47gag-crk proteins expressed in Escherichia coli that have the intact SH2 and SH2' regions retained the capacity to bind ptyr-containing proteins obtained from cells transformed by crk and src. The deletion o...

Oncogene mutational profile in nasopharyngeal carcinoma

Directory of Open Access Journals (Sweden)

Zhang ZC

2014-03-01

Full Text Available Zi-Chen Zhang,1,* Sha Fu,1,* Fang Wang,1 Hai-Yun Wang,1 Yi-Xin Zeng,2 Jian-Yong Shao11Department of Molecular Diagnostics, 2Department of Experimental Research, Sun Yat-sen University Cancer Center, State Key Laboratory of Oncology in South China, Collaborative Innovation Center of Cancer Medicine, Guangzhou, People's Republic of China *These authors contributed equally to this work Abstract: Nasopharyngeal carcinoma (NPC is a common tumor in Southern China, but the oncogene mutational status of NPC patients has not been clarified. Using time-of-flight mass spectrometry, 238 mutation hotspots in 19 oncogenes were examined in 123 NPC patients. The relationships between mutational status and clinical data were assessed with a χ2 or Fisher's exact test. Survival analysis was performed using the Kaplan–Meier method with the log-rank test. In 123 patients, 21 (17.1% NPC tumors were positive for mutations in eight oncogenes: six patients had PIK3CA mutations (4.9%, five NRAS mutations (4.1%, four KIT mutations (3.3%, two PDGFRA mutations (1.6%, two ABL mutations (1.6%, and one with simultaneous mutations in HRAS, EGFR, and BRAF (1%. Patients with mutations were more likely to relapse or develop metastasis than those with wild-type alleles (P=0.019. No differences or correlations were found in other clinical characteristics or in patient survival. No mutations were detected in oncogenes AKT1, AKT2, CDK, ERBB2, FGFR1, FGFR3, FLT3, JAK2, KRAS, MET, and RET. These results demonstrate an association between NPC and mutations in NRAS, KIT, PIK3CA, PDGFRA, and ABL, which are associated with patient relapse and metastasis. Keywords: NPC, oncogene, mutation

Two novel genital human papillomavirus (HPV) types, HPV68 and HPV70, related to the potentially oncogenic HPV39.

OpenAIRE

Longuet, M; Beaudenon, S; Orth, G

1996-01-01

The genomes of two novel human papillomavirus (HPV) types, HPV68 and HPV70, were cloned from a low-grade cervical intraepithelial neoplasia and a vulvar papilloma, respectively, and partially sequenced. Both types are related to HPV39, a potentially oncogenic virus. HPV68 and HPV70 were also detected in genital intraepithelial neoplasia from three patients and one patient, respectively. Comparison with sequence data in the literature indicates that the subgenomic ME180-HPV DNA fragment, clone...

Oncogenes and radiation resistance - a review

International Nuclear Information System (INIS)

Dritschilo, A.

1992-01-01

Oncogenes exert their effects on the genetic programs of cells by regulating signal transduction pathways, resulting in multi-factorial genetic responses. By such actions, the genetic elements responsible for the cellular responses to ionizing radiation may be affected. Reports implicating the association of oncogene expression with modulation of the radiation response include the ras, raf, and myc genes. Experiments overexpressing H-ras and c-raf-1 using genetically engineered constructs result in enhanced post-radiation cellular survival. Conversely, inhibition of raf gene expression has resulted in relative radiation sensitization and delay of human squamous cell carcinoma tumor growth in nude mice. There appears to be a potential strategy for therapeutic intervention. The identification of genes that confer survival advantage following radiation exposure, and understanding their mechanisms of action, may permit a genetically based intervention for radiation sensitization. One such approach employs oligo-deoxynucleotides complementary to oncogene-encoded in RNA's (antisense DNA). (author)

Research update: Avian Disease and Oncology Laboratory avian tumor viruses

Science.gov (United States)

Genomics and Immunogenetics Use of genomics to identify QTL, genes, and proteins associated with resistance to Marek’s disease. Marek’s disease (MD), a lymphoproliferative disease caused by the highly oncogenic herpesvirus Marek's disease virus (MDV), continues to be a major disease concern to the p...

A Screen Identifies the Oncogenic Micro-RNA miR-378a-5p as a Negative Regulator of Oncogene-Induced Senescence

DEFF Research Database (Denmark)

Kooistra, Susanne Marije; Rudkjær, Lise Christine; Lees, Michael James

2014-01-01

Oncogene-induced senescence (OIS) can occur in response to hyperactive oncogenic signals and is believed to be a fail-safe mechanism protecting against tumorigenesis. To identify new factors involved in OIS, we performed a screen for microRNAs that can overcome or inhibit OIS in human diploid fib...

DNA damage and repair in oncogenic transformation by heavy ion radiation

Science.gov (United States)

Yang, T. C.; Mei, M.; George, K. A.; Craise, L. M.

1996-01-01

Energetic heavy ions are present in galactic cosmic rays and solar particle events. One of the most important late effects in risk assessment is carcinogenesis. We have studied the carcinogenic effects of heavy ions at the cellular and molecular levels and have obtained quantitative data on dose-response curves and on the repair of oncogenic lesions for heavy particles with various charges and energies. Studies with repair inhibitors and restriction endonucleases indicated that for oncogenic transformation DNA is the primary target. Results from heavy ion experiments showed that the cross section increased with LET and reached a maximum value of about 0.02 micrometer2 at about 500 keV/micrometer. This limited size of cross section suggests that only a fraction of cellular genomic DNA is important in radiogenic transformation. Free radical scavengers, such as DMSO, do not give any effect on induction of oncogenic transformation by 600 MeV/u iron particles, suggesting most oncogenic damage induced by high-LET heavy ions is through direct action. Repair studies with stationary phase cells showed that the amount of reparable oncogenic lesions decreased with an increase of LET and that heavy ions with LET greater than 200 keV/micrometer produced only irreparable oncogenic damage. An enhancement effect for oncogenic transformation was observed in cells irradiated by low-dose-rate argon ions (400 MeV/u; 120 keV/micrometer). Chromosomal aberrations, such as translocation and deletion, but not sister chromatid exchange, are essential for heavy-ion-induced oncogenic transformation. The basic mechanism(s) of misrepair of DNA damage, which form oncogenic lesions, is unknown.

Viruses and oral cancer. Is there a link?

Science.gov (United States)

Sand, Lars; Jalouli, Jamshid

2014-05-01

Oral squamous cell carcinoma (OSCC) is the most common malignant tumour of the oral cavity. The aetiology of epithelial cancer of the head and neck is considered to be a multifactorial, sequential process. DNA viruses are found in many different cancers and are also capable of transforming cells to a malignant phenotype. Human Papilloma Virus (HPV) has been proposed as risk factors in OSCC development and HPV type 16 is the most important subtype. Other oncogenic virus species i.e., Epstein-Barr Virus and Herpes Simplex Virus Type 1 have been proposed to be involved in oral carcinogenesis. However, no convincing evidence exist that they are an established risk factor in OSCC. Therefore more studies are needed in order to clarify the different aspects of virus involvement. Here, we review the existing literature on viral involvement in oral cancer. Copyright © 2014 Institut Pasteur. Published by Elsevier Masson SAS. All rights reserved.

Carcinoma de células escamosas oral - contribuição de vírus oncogênicos e alguns marcadores moleculares no desenvolvimento e prognóstico da lesão: uma revisão Oral squamous cell carcinoma - contribution of oncogenic virus and some molecular markers in the development and prognosis of the lesion: a review

Directory of Open Access Journals (Sweden)

Beatriz da Rocha Miranda Venturi

2004-06-01

Full Text Available O carcinoma de células escamosas oral é um evento de muitas etapas, cuja incidência cresce continuamente, particularmente em jovens, numa amplitude que não pode ser completamente explicada pelo aumento da exposição a fatores de risco, como o tabaco e o álcool. Recentes investigações moleculares sugerem que existem múltiplos eventos genéticos, e vírus oncogênicos que são capazes de alterar as funções normais de oncogenes e genes de supressão tumoral. O objetivo deste artigo foi revisar o conhecimento atual sobre o papel do papilomavírus humano (HPV, Epstein-Barr vírus (EBV, P53 e telomerase no desenvolvimento e prognóstico do carcinoma de células escamosas oral.Oral squamous cell carcinoma is a multistep event that continues to increase in incidence, particularly in the young, and to an extent that cannot be fully explained by increased exposure to known risk factors, as tobacco or alcohol. Recent molecular investigations suggest that there are multiple genetic events, and oncogenic virus that are able to alter the normal functions of oncogenes and tumor suppressor genes. The aim of the present article was to review the current knowledge on the role of Human papillomavirus (HPV, Epstein-Barr virus (EBV, P53 and telomerase in the development and prognosis of the oral squamous cell carcinoma.

Expression of Mitochondrial Non-coding RNAs (ncRNAs) Is Modulated by High Risk Human Papillomavirus (HPV) Oncogenes*

Science.gov (United States)

Villota, Claudio; Campos, América; Vidaurre, Soledad; Oliveira-Cruz, Luciana; Boccardo, Enrique; Burzio, Verónica A.; Varas, Manuel; Villegas, Jaime; Villa, Luisa L.; Valenzuela, Pablo D. T.; Socías, Miguel; Roberts, Sally; Burzio, Luis O.

2012-01-01

The study of RNA and DNA oncogenic viruses has proved invaluable in the discovery of key cellular pathways that are rendered dysfunctional during cancer progression. An example is high risk human papillomavirus (HPV), the etiological agent of cervical cancer. The role of HPV oncogenes in cellular immortalization and transformation has been extensively investigated. We reported the differential expression of a family of human mitochondrial non-coding RNAs (ncRNAs) between normal and cancer cells. Normal cells express a sense mitochondrial ncRNA (SncmtRNA) that seems to be required for cell proliferation and two antisense transcripts (ASncmtRNAs). In contrast, the ASncmtRNAs are down-regulated in cancer cells. To shed some light on the mechanisms that trigger down-regulation of the ASncmtRNAs, we studied human keratinocytes (HFK) immortalized with HPV. Here we show that immortalization of HFK with HPV-16 or 18 causes down-regulation of the ASncmtRNAs and induces the expression of a new sense transcript named SncmtRNA-2. Transduction of HFK with both E6 and E7 is sufficient to induce expression of SncmtRNA-2. Moreover, E2 oncogene is involved in down-regulation of the ASncmtRNAs. Knockdown of E2 in immortalized cells reestablishes in a reversible manner the expression of the ASncmtRNAs, suggesting that endogenous cellular factors(s) could play functions analogous to E2 during non-HPV-induced oncogenesis. PMID:22539350

Expression of mitochondrial non-coding RNAs (ncRNAs) is modulated by high risk human papillomavirus (HPV) oncogenes.

Science.gov (United States)

Villota, Claudio; Campos, América; Vidaurre, Soledad; Oliveira-Cruz, Luciana; Boccardo, Enrique; Burzio, Verónica A; Varas, Manuel; Villegas, Jaime; Villa, Luisa L; Valenzuela, Pablo D T; Socías, Miguel; Roberts, Sally; Burzio, Luis O

2012-06-15

The study of RNA and DNA oncogenic viruses has proved invaluable in the discovery of key cellular pathways that are rendered dysfunctional during cancer progression. An example is high risk human papillomavirus (HPV), the etiological agent of cervical cancer. The role of HPV oncogenes in cellular immortalization and transformation has been extensively investigated. We reported the differential expression of a family of human mitochondrial non-coding RNAs (ncRNAs) between normal and cancer cells. Normal cells express a sense mitochondrial ncRNA (SncmtRNA) that seems to be required for cell proliferation and two antisense transcripts (ASncmtRNAs). In contrast, the ASncmtRNAs are down-regulated in cancer cells. To shed some light on the mechanisms that trigger down-regulation of the ASncmtRNAs, we studied human keratinocytes (HFK) immortalized with HPV. Here we show that immortalization of HFK with HPV-16 or 18 causes down-regulation of the ASncmtRNAs and induces the expression of a new sense transcript named SncmtRNA-2. Transduction of HFK with both E6 and E7 is sufficient to induce expression of SncmtRNA-2. Moreover, E2 oncogene is involved in down-regulation of the ASncmtRNAs. Knockdown of E2 in immortalized cells reestablishes in a reversible manner the expression of the ASncmtRNAs, suggesting that endogenous cellular factors(s) could play functions analogous to E2 during non-HPV-induced oncogenesis.

Large-scale analysis by SAGE reveals new mechanisms of v-erbA oncogene action

Directory of Open Access Journals (Sweden)

Faure Claudine

2007-10-01

Full Text Available Abstract Background: The v-erbA oncogene, carried by the Avian Erythroblastosis Virus, derives from the c-erbAα proto-oncogene that encodes the nuclear receptor for triiodothyronine (T3R. v-ErbA transforms erythroid progenitors in vitro by blocking their differentiation, supposedly by interference with T3R and RAR (Retinoic Acid Receptor. However, v-ErbA target genes involved in its transforming activity still remain to be identified. Results: By using Serial Analysis of Gene Expression (SAGE, we identified 110 genes deregulated by v-ErbA and potentially implicated in the transformation process. Bioinformatic analysis of promoter sequence and transcriptional assays point out a potential role of c-Myb in the v-ErbA effect. Furthermore, grouping of newly identified target genes by function revealed both expected (chromatin/transcription and unexpected (protein metabolism functions potentially deregulated by v-ErbA. We then focused our study on 15 of the new v-ErbA target genes and demonstrated by real time PCR that in majority their expression was activated neither by T3, nor RA, nor during differentiation. This was unexpected based upon the previously known role of v-ErbA. Conclusion: This paper suggests the involvement of a wealth of new unanticipated mechanisms of v-ErbA action.

Interplay of viruses and radiation in carcinogenesis

International Nuclear Information System (INIS)

Upton, A.C.

1975-01-01

The discovery by Gross and by Lieberman and Kaplan that leukemias induced by irradiation in mice may be transmissible by cell-free filtrates pointed to the existence of an interplay between the effects of radiation and those of an otherwise latent oncogenic virus, which has since been the subject of intensive study. In the years intervening since these pioneer observations, efforts have been made to elucidate the nature and mechanisms of the interplay and to determine whether other neoplasms also may be elicited by an interaction between virus and radiation. The results of these efforts, although still highly preliminary, are surveyed in the light of recent advances in viral oncology

Adenovirus-Mediated Delivery of Decoy Hyper Binding Sites Targeting Oncogenic HMGA1 Reduces Pancreatic and Liver Cancer Cell Viability.

Science.gov (United States)

Hassan, Faizule; Ni, Shuisong; Arnett, Tyler C; McKell, Melanie C; Kennedy, Michael A

2018-03-30

High mobility group AT-hook 1 (HMGA1) protein is an oncogenic architectural transcription factor that plays an essential role in early development, but it is also implicated in many human cancers. Elevated levels of HMGA1 in cancer cells cause misregulation of gene expression and are associated with increased cancer cell proliferation and increased chemotherapy resistance. We have devised a strategy of using engineered viruses to deliver decoy hyper binding sites for HMGA1 to the nucleus of cancer cells with the goal of sequestering excess HMGA1 at the decoy hyper binding sites due to binding competition. Sequestration of excess HMGA1 at the decoy binding sites is intended to reduce HMGA1 binding at the naturally occurring genomic HMGA1 binding sites, which should result in normalized gene expression and restored sensitivity to chemotherapy. As proof of principle, we engineered the replication defective adenovirus serotype 5 genome to contain hyper binding sites for HMGA1 composed of six copies of an individual HMGA1 binding site, referred to as HMGA-6. A 70%-80% reduction in cell viability and increased sensitivity to gemcitabine was observed in five different pancreatic and liver cancer cell lines 72 hr after infection with replication defective engineered adenovirus serotype 5 virus containing the HMGA-6 decoy hyper binding sites. The decoy hyper binding site strategy should be general for targeting overexpression of any double-stranded DNA-binding oncogenic transcription factor responsible for cancer cell proliferation.

The oncogenic action of ionizing radiation on rat skin

International Nuclear Information System (INIS)

Burns, F.J.

1991-01-01

Progress has occurred in several areas corresponding to the specific aims of the proposal: (1) Progression and multiple events in radiation carcinogenesis of rat skin as a function of LET; (2) cell cycle kinetics of irradiated rat epidermis as determined by double labeling and double emulsion autoradiography; (3) oncogene activation detected by in situ hybridization in radiation-induced rat skin tumors; (4) amplification of the c-myc oncogene in radiation-induced rat skin tumors as a function of LET; and (5) transformation of rat skin keratinocytes by ionizing radiation in combination with c-Ki-ras and c-myc oncogenes. 111 refs., 13 figs., 12 tabs

Oncogenic osteomalacia associated with soft tissue chondromyxoid fibroma

International Nuclear Information System (INIS)

Park, Jeong Mi; Woo, Young Kyun; Kang, Moo Il; Kang, Chang Suk; Hahn, Seong Tae

2001-01-01

Oncogenic osteomalacia is a rarely described clinical entity characterized by hypophosphatemia, phosphaturia, and a low concentration of 1,25-dihydroxyvitamin D 3 . It is most often associated with benign mesenchymal tumor and can be cured with surgical removal of the tumor. In this paper, we present a case of oncogenic osteomalacia caused by chondromyxoid fibroma in the soft tissue of the sole of the foot in a 56-year-old woman

Targeting MET Amplification as a New Oncogenic Driver

International Nuclear Information System (INIS)

Kawakami, Hisato; Okamoto, Isamu; Okamoto, Wataru; Tanizaki, Junko; Nakagawa, Kazuhiko; Nishio, Kazuto

2014-01-01

Certain genetically defined cancers are dependent on a single overactive oncogene for their proliferation and survival, a phenomenon known as “oncogene addiction”. A new generation of drugs that selectively target such “driver oncogenes” manifests a clinical efficacy greater than that of conventional chemotherapy in appropriate genetically defined patients. MET is a proto-oncogene that encodes a receptor tyrosine kinase, and aberrant activation of MET signaling occurs in a subset of advanced cancers as result of various genetic alterations including gene amplification, polysomy, and gene mutation. Our preclinical studies have shown that inhibition of MET signaling either with the small-molecule MET inhibitor crizotinib or by RNA interference targeted to MET mRNA resulted in marked antitumor effects in cancer cell lines with MET amplification both in vitro and in vivo. Furthermore, patients with non-small cell lung cancer or gastric cancer positive for MET amplification have shown a pronounced clinical response to crizotinib. Accumulating preclinical and clinical evidence thus suggests that MET amplification is an “oncogenic driver” and therefore a valid target for treatment. However, the prevalence of MET amplification has not been fully determined, possibly in part because of the difficulty in evaluating gene amplification. In this review, we provide a rationale for targeting this genetic alteration in cancer therapy

Targeting MET Amplification as a New Oncogenic Driver

Energy Technology Data Exchange (ETDEWEB)

Kawakami, Hisato [Department of Medical Oncology, Kinki University Faculty of Medicine, 377-2 Ohno-higashi, Osaka-Sayama, Osaka 589-8511 (Japan); Okamoto, Isamu, E-mail: okamotoi@kokyu.med.kyushu-u.ac.jp [Department of Medical Oncology, Kinki University Faculty of Medicine, 377-2 Ohno-higashi, Osaka-Sayama, Osaka 589-8511 (Japan); Center for Clinical and Translational Research, Kyushu University Hospital, 3-1-1 Maidashi, Higashiku, Fukuoka 812-8582 (Japan); Okamoto, Wataru [Department of Medical Oncology, Kinki University Faculty of Medicine, 377-2 Ohno-higashi, Osaka-Sayama, Osaka 589-8511 (Japan); Division of Transrlational Research, Exploratory Oncology Research & Clinical Trial Center, National Cancer Center, 6-5-1 Kashiwanoha, Kashiwa, Chiba 277-8577 (Japan); Tanizaki, Junko [Department of Medical Oncology, Kinki University Faculty of Medicine, 377-2 Ohno-higashi, Osaka-Sayama, Osaka 589-8511 (Japan); Lowe Center for Thoracic Oncology, Dana-Farber Cancer Institute, HIM223, 450 Brookline Avenue, Boston, MA 02215 (United States); Nakagawa, Kazuhiko [Department of Medical Oncology, Kinki University Faculty of Medicine, 377-2 Ohno-higashi, Osaka-Sayama, Osaka 589-8511 (Japan); Nishio, Kazuto [Department of Genome Biology, Kinki University Faculty of Medicine, 377-2 Ohno-higashi, Osaka-Sayama, Osaka 589-8511 (Japan)

2014-07-22

Certain genetically defined cancers are dependent on a single overactive oncogene for their proliferation and survival, a phenomenon known as “oncogene addiction”. A new generation of drugs that selectively target such “driver oncogenes” manifests a clinical efficacy greater than that of conventional chemotherapy in appropriate genetically defined patients. MET is a proto-oncogene that encodes a receptor tyrosine kinase, and aberrant activation of MET signaling occurs in a subset of advanced cancers as result of various genetic alterations including gene amplification, polysomy, and gene mutation. Our preclinical studies have shown that inhibition of MET signaling either with the small-molecule MET inhibitor crizotinib or by RNA interference targeted to MET mRNA resulted in marked antitumor effects in cancer cell lines with MET amplification both in vitro and in vivo. Furthermore, patients with non-small cell lung cancer or gastric cancer positive for MET amplification have shown a pronounced clinical response to crizotinib. Accumulating preclinical and clinical evidence thus suggests that MET amplification is an “oncogenic driver” and therefore a valid target for treatment. However, the prevalence of MET amplification has not been fully determined, possibly in part because of the difficulty in evaluating gene amplification. In this review, we provide a rationale for targeting this genetic alteration in cancer therapy.

Transformation of human fibroblasts by ionizing radiation, a chemical carcinogen, or simian virus 40 correlates with an increase in susceptibility to the autonomous parvoviruses H-1 virus and minute virus of mice

International Nuclear Information System (INIS)

Cornelis, J.J.; Becquart, P.; Duponchel, N.; Salome, N.; Avalosse, B.L.; Namba, M.; Rommelaere, J.

1988-01-01

Morphologically altered and established human fibroblasts, obtained either by 60 Co gamma irradiation, treatment with the carcinogen 4-nitroquinoline 1-oxide, or simian virus 40 (SV40) infection, were compared with their normal finite-life parental strains for susceptibility to the autonomous parvoviruses H-1 virus and the prototype strain of minute virus of mice (MVMp). All transformed cells suffered greater virus-induced killing than their untransformed progenitors. The cytotoxic effect of H-1 virus was more severe than that of MVMp. Moreover, the level of viral DNA replication was much (10- to 85-fold) enhanced in the transformants compared with their untransformed parent cells. Thus, in this system, cell transformation appears to correlate with an increase in both DNA amplification and cytotoxicity of the parvoviruses. However, the accumulation of parvovirus DNA in the transformants was not always accompanied by the production of infectious virus. Like in vitro-transformed fibroblasts, a fibrosarcoma-derived cell line was sensitive to the killing effect of both H-1 virus and MVMp and amplified viral DNA to high extents. The results indicate that oncogenic transformation can be included among cellular states which modulate permissiveness to parvoviruses under defined growth conditions

Oncogenic osteomalacia associated with soft tissue chondromyxoid fibroma

Energy Technology Data Exchange (ETDEWEB)

Park, Jeong Mi E-mail: jmpark@cmc.cuk.ac.kr; Woo, Young Kyun; Kang, Moo Il; Kang, Chang Suk; Hahn, Seong Tae

2001-08-01

Oncogenic osteomalacia is a rarely described clinical entity characterized by hypophosphatemia, phosphaturia, and a low concentration of 1,25-dihydroxyvitamin D{sub 3}. It is most often associated with benign mesenchymal tumor and can be cured with surgical removal of the tumor. In this paper, we present a case of oncogenic osteomalacia caused by chondromyxoid fibroma in the soft tissue of the sole of the foot in a 56-year-old woman.

Regulation of expression of the c-sis proto-oncogene

Energy Technology Data Exchange (ETDEWEB)

Ratner, L. (Washington Univ., St. Louis, MO (USA))

1989-06-12

Regulation of expression of platelet derived growth factor polypeptide B encoded by the c-sis proto-oncogene is important in a number of physiological and pathological conditions. Sequences in the 1,028 nucleotide long 5{prime} untranslated region of the c-sis mRNA were found to inhibit protein synthesis. The inhibition is relieved by deletion of nucleotides 154-378 or 398-475. Sequences within 375 nucleotides upstream of the RNA initiation sites are important for transcriptional activity. Sequences in two portions of this region, between {minus}375 and {minus}235 nucleotides and between {minus}235 and {minus}99 nucleotides relative to the RNA CAP site are important for full activity. A transcriptional enhancer activity is demonstrated by its ability to increase the activity of the human T lymphotropic virus type (HTLV) I promoter at a distance and in an orientation-independent manner. Furthermore, sequences upstream of the c-sis RNA CAP site respond to the HTLV I transactivator protein to increase RNA synthesis from either the c-sis or HTLV I promoter.

The application of human papilloma virus genotyping for the identification of neoplasm lesions in the cervix of women with abnormal cytology smears.

Science.gov (United States)

Ciszek, Barbara; Heimrath, Jerzy; Ciszek, Marian

2012-01-01

A connection between infections with a highly oncogenic type of human papilloma virus and the development of cervical intraepithelial neoplasia and preinvasive cervical cancer has been proven both experimentally and clinically. The period after which persistent virus infection will lead to the development of precancerous and invasive lesions is dependent on, among others, the HPV genotype. The oncogenic types of human papilloma virus destabilize the genome of an infected cell and thus initiate the carcinogenesis process. The aim of this work was to analyze the frequency of occurrence of different oncogenic HPV genotypes among women with abnormal cytological smears and the correlation of this data with the degree of cervical intraepithelial neoplasia exacerbation. The sample consisted of 75 women of child-bearing age (16-43 years old) with an abnormal cytological smear and positive test identifying an infection with an oncogenic type of human papilloma virus. In every case histopathological verification, aimed at excluding pathologies in the endocervix, was conducted using a colposcopy with guided biopsy and cervix abrasion. The authors found that the frequency of occurrence of different HPV genotypes of the groups of cytological diagnoses ASC-US, LSIL and HSIL do not differ statistically (p = 0.57). However, what is noteworthy is the more common occurrence of HPV 16 in type LSIL lesions (45.45%) and HPV 18 of a more advanced type HSIL (37.50%) pathology. Through the verification of the cytology results with histopathological diagnosis of the above groups the authors obtained statistically significant differences (p human papilloma virus, the authors found that the most common were HPV 31, 45 and 33. In CIN 1 and CIN 2 their share was over 60%. In CIS/AIS type pathologies, no other types of human papilloma virus than HPV 16 and HPV 18 were shown. Positive results of DNA HR HPV testing of women with abnormal cytology results identified a risk group for the

Problem-Solving Test: The Mechanism of Action of a Human Papilloma Virus Oncoprotein

Science.gov (United States)

Szeberenyi, Jozsef

2009-01-01

Terms to be familiar with before you start to solve the test: human papilloma virus; cervical cancer; oncoproteins; malignant transformation; retinoblastoma protein; cell cycle; quiescent and cycling cells; cyclin/cyclin-dependent kinase (Cdk) complexes; E2F; S-phase genes; enhancer element; proto-oncogenes; tumor suppressor genes; radioactive…

Transformation and oncogenicity by Adenoviruses

NARCIS (Netherlands)

Bernards, R.A.; Eb, A.J. van der

1984-01-01

Adenoviruses have attracted considerable attention since it was discovered by TRENTIN et all. and HUEBNER et al. that certain species (formerly called serotypes) are oncogenic when injected into newborn hamsters. Since then, adenoviruses have been used extensively as a model for studies on tumor

Oncogene expression in primary lung tumors in dogs that inhaled 239PuO2

International Nuclear Information System (INIS)

Kelly, G.; Kerkof, P.R.; Haley, P.J.

1988-01-01

Ten radiation-induced and three spontaneous lung tumors were analyzed for aberrant expression of known oncogenes. In 12 of 13 tumors tested, sequences hybridizing to the c-myc oncogene were expressed at levels 1.5 times higher than sequences hybridizing to β-actin. This level of oncogene expression was also observed in 9 of 13 tumors for 1 or more members of the ras family of oncogenes. Seven of thirteen tumors examined express sequences that hybridize with clones of v-ros or c-met. The ros and met clones both code for oncogenes whose normal homologues are transmembrane proteins related to the insulin receptor. (author)

Targeting oncogenic Myc as a strategy for cancer treatment.

Science.gov (United States)

Chen, Hui; Liu, Hudan; Qing, Guoliang

2018-01-01

The MYC family oncogene is deregulated in >50% of human cancers, and this deregulation is frequently associated with poor prognosis and unfavorable patient survival. Myc has a central role in almost every aspect of the oncogenic process, orchestrating proliferation, apoptosis, differentiation, and metabolism. Although Myc inhibition would be a powerful approach for the treatment of many types of cancers, direct targeting of Myc has been a challenge for decades owing to its "undruggable" protein structure. Hence, alternatives to Myc blockade have been widely explored to achieve desirable anti-tumor effects, including Myc/Max complex disruption, MYC transcription and/or translation inhibition, and Myc destabilization as well as the synthetic lethality associated with Myc overexpression. In this review, we summarize the latest advances in targeting oncogenic Myc, particularly for cancer therapeutic purposes.

Modulating factors in the expression of radiation-induced oncogenic transformation

International Nuclear Information System (INIS)

Hall, E.J.; Hei, T.K.

1990-01-01

Many assays for oncogenic transformation have been developed ranging from those in established rodent cell lines where morphological alteration is scored, to those in human cells growing in nude mice where tumor invasiveness is scored. In general, systems that are most quantitaive are also the least relevant in terms of human carcinogenesis and human risk estimation. The development of cell culture systems has made it possible to assess at the cellular level the oncogenic potential of a variety of chemical, physical and viral agents. Cell culture systems afford the opportunity to identify factors and conditions that may prevent or enhance cellular transformation by radiation and chemicals. Permissive and protective factors in radiation-induced transformation include thyroid hormone and the tumor promoter TPA that increase the transformation incidence for a given dose of radiation, and retinoids, selenium, vitamin E, and 5-aminobenzamide that inhibit the expression of transformation. Densely ionizing α-particles, similar to those emitted by radon daughters, are highly effective in inducing transformations and appear to interact in a supra-additive fashion with asbestos fibers. The activation of a known dominant oncogene has not yet been demonstrated in radiation-induced oncogenic transformation. The most likely mechanism for radiation activation of an oncogene would be via the production of a chromosomal translocation. Radiation also efficiently induces deletions and may thus lead to the loss of a suppressor gene

Discordance between bovine leukemia virus tax immortalization in vitro and oncogenicity in vivo.

Science.gov (United States)

Twizere, J C; Kerkhofs, P; Burny, A; Portetelle, D; Kettmann, R; Willems, L

2000-11-01

Bovine leukemia virus (BLV) Tax protein, a transcriptional activator of viral expression, is essential for viral replication in vivo. Tax is believed to be involved in leukemogenesis because of its second function, immortalization of primary cells in vitro. These activities of Tax can be dissociated on the basis of point mutations within specific regions of the protein. For example, mutation of the phosphorylation sites at serines 106 and 293 abrogates immortalization potential in vitro but maintains transcriptional activity. This type of mutant is thus particularly useful for unraveling the role of Tax immortalization activity during leukemogenesis independently of viral replication. In this report, we describe the biological properties of BLV recombinant proviruses mutated in the Tax phosphorylation sites (BLVTax106+293). Titration of the proviral loads by semiquantitative PCR revealed that the BLV mutants propagated at wild-type levels in vivo. Furthermore, two animals (sheep 480 and 296) infected with BLVTax106+293 developed leukemia or lymphosarcoma after 16 and 36 months, respectively. These periods of time are within the normal range of latencies preceding the onset of pathogenesis induced by wild-type viruses. The phenotype of the mutant-infected cells was characteristic of a B lymphocyte (immunoglobulin M positive) expressing CD11b and CD5 (except at the final stage for the latter marker), a pattern that is typical of wild-type virus-infected target cells. Interestingly, the transformed B lymphocytes from sheep 480 also coexpressed the CD8 marker, a phenotype rarely observed in tumor biopsies from chronic lymphocytic leukemia patients. Finally, direct sequencing of the tax gene demonstrated that the leukemic cells did not harbor revertant proviruses. We conclude that viruses expressing a Tax mutant unable to transform primary cells in culture are still pathogenic in the sheep animal model. Our data thus provide a clear example of the discordant conclusions

Oncogenic transformation with radiation and chemicals: review

International Nuclear Information System (INIS)

Hall, E.J.; Hei, T.K.

1985-01-01

Quantitative in vitro assay systems for oncogenic transformation are a powerful research tool. They may be based on short-term cultures of hamster embryo cells, or established cell lines of mouse origin. While X-ray-induced transformation of human cells has been demonstrated, it has proved difficult to develop quantitative assay systems based on cells of human origin. The presently available quantitative assays have two quite distinct basic uses. First, they may be useful to accumulate data which is essentially pragmatic in nature. For example, they may be used to compare and contrast the oncogenic potential of chemotherapeutic agents or hypoxic cell sensitizers used or proposed in the clinic. They may be used to identify compounds that inhibit or suppress the transformation incidence resulting from known oncogenic agents, or they may be used to demonstrate the interaction between two different agents, such as radiation and asbestos. Second, they may prove to be invaluable in the study of the basic mechanisms of carcinogenesis, inasmuch as they represent models of tumourigenesis in which the various steps can be manipulated and modified more readily and in a controlled way. (author)

Oncogenic osteomalacia diagnosed by blood pool scintigraphy

International Nuclear Information System (INIS)

Palaniswamy, Shanmuga Sundaram; Subramanyam, Padma; Kumar, Harish

2011-01-01

Oncogenic osteomalacia is a rare metabolic bone disease characterized by phosphaturia and hypophosphatemia. Certain tumors secrete a phosphaturic factor, which results in this metabolic abnormality; this factor called as phosphatonin, is in fact a fibroblast growth factor 23 (FGF-23) involved closely in phosphate homeostasis and skeletogenesis. Complete excision of these tumors facilitates reversal of the problem. We have reported here the case of a patient who was crippled with this disease and on thorough investigation revealed an oncogenic osteomalacia with tumor focus in the right tibia. The tumor was identified as a mesenchymal tumor, i.e., hemangiopericytoma. Tumor excision alleviated patient symptoms with rapid symptomatic and biochemical improvement

Extracellular vesicle communication pathways as regulatory targets of oncogenic transformation.

Science.gov (United States)

Choi, Dongsic; Lee, Tae Hoon; Spinelli, Cristiana; Chennakrishnaiah, Shilpa; D'Asti, Esterina; Rak, Janusz

2017-07-01

Pathogenesis of human cancers bridges intracellular oncogenic driver events and their impact on intercellular communication. Among multiple mediators of this 'pathological connectivity' the role of extracellular vesicles (EVs) and their subsets (exosomes, ectosomes, oncosomes) is of particular interest for several reasons. The release of EVs from cancer cells represents a unique mechanism of regulated expulsion of bioactive molecules, a process that also mediates cell-to-cell transfer of lipids, proteins, and nucleic acids. Biological effects of these processes have been implicated in several aspects of cancer-related pathology, including tumour growth, invasion, angiogenesis, metastasis, immunity and thrombosis. Notably, the emerging evidence suggests that oncogenic mutations may impact several aspects of EV-mediated cell-cell communication including: (i) EV release rate and protein content; (ii) molecular composition of cancer EVs; (iii) the inclusion of oncogenic and mutant macromolecules in the EV cargo; (iv) EV-mediated release of genomic DNA; (v) deregulation of mechanisms responsible for EV biogenesis (vesiculome) and (vi) mechanisms of EV uptake by cancer cells. Intriguingly, EV-mediated intercellular transfer of mutant and oncogenic molecules between subpopulations of cancer cells, their indolent counterparts and stroma may exert profound biological effects that often resemble (but are not tantamount to) oncogenic transformation, including changes in cell growth, clonogenicity and angiogenic phenotype, or cause cell stress and death. However, several biological barriers likely curtail a permanent horizontal transformation of normal cells through EV-mediated mechanisms. The ongoing analysis and targeting of EV-mediated intercellular communication pathways can be viewed as a new therapeutic paradigm in cancer, while the analysis of oncogenic cargo contained in EVs released from cancer cells into biofluids is being developed for clinical use as a biomarker

Characterization of a Suppressive Cis-acting Element in the Epstein–Barr Virus LMP1 Promoter

Directory of Open Access Journals (Sweden)

Masahiro Yoshida

2017-11-01

Full Text Available Latent membrane protein 1 (LMP1 is a major oncogene encoded by Epstein–Barr virus (EBV and is essential for immortalization of B cells by the virus. Previous studies suggested that several transcription factors, such as PU.1, RBP-Jκ, NFκB, EBF1, AP-2 and STAT, are involved in LMP1 induction; however, the means by which the oncogene is negatively regulated remains unclear. Here, we introduced short mutations into the proximal LMP1 promoter that includes recognition sites for the E-box and Ikaros transcription factors in the context of EBV-bacterial artificial chromosome. Upon infection, the mutant exhibited increased LMP1 expression and EBV-mediated immortalization of B cells. However, single mutations of either the E-box or Ikaros sites had limited effects on LMP1 expression and transformation. Our results suggest that this region contains a suppressive cis-regulatory element, but other transcriptional repressors (apart from the E-box and Ikaros transcription factors may remain to be discovered.

Intragenic origins due to short G1 phases underlie oncogene-induced DNA replication stress.

Science.gov (United States)

Macheret, Morgane; Halazonetis, Thanos D

2018-03-01

Oncogene-induced DNA replication stress contributes critically to the genomic instability that is present in cancer. However, elucidating how oncogenes deregulate DNA replication has been impeded by difficulty in mapping replication initiation sites on the human genome. Here, using a sensitive assay to monitor nascent DNA synthesis in early S phase, we identified thousands of replication initiation sites in cells before and after induction of the oncogenes CCNE1 and MYC. Remarkably, both oncogenes induced firing of a novel set of DNA replication origins that mapped within highly transcribed genes. These ectopic origins were normally suppressed by transcription during G1, but precocious entry into S phase, before all genic regions had been transcribed, allowed firing of origins within genes in cells with activated oncogenes. Forks from oncogene-induced origins were prone to collapse, as a result of conflicts between replication and transcription, and were associated with DNA double-stranded break formation and chromosomal rearrangement breakpoints both in our experimental system and in a large cohort of human cancers. Thus, firing of intragenic origins caused by premature S phase entry represents a mechanism of oncogene-induced DNA replication stress that is relevant for genomic instability in human cancer.

Oncogenic osteomalacia due to FGF23-expressing colon adenocarcinoma.

Science.gov (United States)

Leaf, David E; Pereira, Renata C; Bazari, Hasan; Jüppner, Harald

2013-03-01

Oncogenic osteomalacia, a paraneoplastic syndrome associated with hypophosphatemia due to increased urinary phosphate excretion, is caused by excessive synthesis and secretion of fibroblast growth factor 23 (FGF23), a phosphaturic hormone that is normally produced by osteocytes. Most cases of oncogenic osteomalacia have been associated with benign tumors of bone or soft tissue; however, whether malignant neoplasms can also produce and secrete FGF23 is currently unknown. The aim was to determine whether a malignant neoplasm could cause oncogenic osteomalacia through excessive production and secretion of FGF23. We describe an 80-year-old woman with stage IV colon adenocarcinoma who presented with severe hypophosphatemia (0.4 mg/dL; reference, 2.6-4.5 mg/dL). Fractional excretion of phosphate was 34% (reference, osteomalacia should be considered in the differential diagnosis for patients with a malignant tumor who present with hypophosphatemia.

Studies on the role of RNA tumour viruses in human leukaemia

International Nuclear Information System (INIS)

Nooter, K.

1979-01-01

A search has been made for an etiological role of retroviruses in human leukemia and cocultivation studies have led to the isolation of a presumed human type C virus which appeared to be oncogenic for experimental animals. The experimental procedures and results are fully discussed. The parallels between irradiation induced lymphomas in mice and leukaemias in man are explored. (C.F.)

Oncogene-inducible organoids as a miniature platform to assess cancer characteristics

NARCIS (Netherlands)

Mizutani, Tomohiro; Tsukamoto, Yoshiyuki; Clevers, Hans

2017-01-01

Direct effects of oncogenic proteins or inhibitor treatments on signaling pathways are difficult to assess in transgenic mice. In this issue, Riemer et al. (2017. J. Cell Biol. https://doi.org/10.1083/jcb.201610058) demonstrate that oncogene-inducible organoids offer the experimental versatility of

Prevalence of herpes simplex, Epstein Barr and human papilloma viruses in oral lichen planus.

Science.gov (United States)

Yildirim, Benay; Sengüven, Burcu; Demir, Cem

2011-03-01

The aim of the present study was to assess the prevalence of Herpes Simplex virus, Epstein Barr virus and Human Papilloma virus -16 in oral lichen planus cases and to evaluate whether any clinical variant, histopathological or demographic feature correlates with these viruses. The study was conducted on 65 cases. Viruses were detected immunohistochemically. We evaluated the histopathological and demographic features and statistically analysed correlation of these features with Herpes Simplex virus, Epstein Barr virus and Human Papilloma virus-16 positivity. Herpes Simplex virus was positive in six (9%) cases and this was not statistically significant. The number of Epstein Barr virus positive cases was 23 (35%) and it was statistically significant. Human Papilloma virus positivity in 14 cases (21%) was statistically significant. Except basal cell degeneration in Herpes Simplex virus positive cases, we did not observe any significant correlation between virus positivity and demographic or histopathological features. However an increased risk of Epstein Barr virus and Human Papilloma virus infection was noted in oral lichen planus cases. Taking into account the oncogenic potential of both viruses, oral lichen planus cases should be detected for the presence of these viruses.

Epstein-Barr virus-kodet BILF1 er en konstitutivt aktiv G-protein-koblede receptor

DEFF Research Database (Denmark)

Paulsen, Sarah J; Rosenkilde, Mette M; Eugen-Olsen, Jesper

2005-01-01

væsentligste Oncogene i Kaposis sarkom patogenese. I modsætning hertil den nuværende annotation af Epstein-Barr virus (EBV) genom ikke afslører nogen GPCR homolog kodet af denne menneskelige onkogene gamma1-herpesvirus. Men, ved at anvende bioinformatik, anerkendte vi, at den tidligere fastsatte EBV åben...

HPV integration hijacks and multimerizes a cellular enhancer to generate a viral-cellular super-enhancer that drives high viral oncogene expression

Science.gov (United States)

Redmond, Catherine J.; Dooley, Katharine E.; Fu, Haiqing; Gillison, Maura L.; Akagi, Keiko; Symer, David E.; Aladjem, Mirit I.

2018-01-01

Integration of human papillomavirus (HPV) genomes into cellular chromatin is common in HPV-associated cancers. Integration is random, and each site is unique depending on how and where the virus integrates. We recently showed that tandemly integrated HPV16 could result in the formation of a super-enhancer-like element that drives transcription of the viral oncogenes. Here, we characterize the chromatin landscape and genomic architecture of this integration locus to elucidate the mechanisms that promoted de novo super-enhancer formation. Using next-generation sequencing and molecular combing/fiber-FISH, we show that ~26 copies of HPV16 are integrated into an intergenic region of chromosome 2p23.2, interspersed with 25 kb of amplified, flanking cellular DNA. This interspersed, co-amplified viral-host pattern is frequent in HPV-associated cancers and here we designate it as Type III integration. An abundant viral-cellular fusion transcript encoding the viral E6/E7 oncogenes is expressed from the integration locus and the chromatin encompassing both the viral enhancer and a region in the adjacent amplified cellular sequences is strongly enriched in the super-enhancer markers H3K27ac and Brd4. Notably, the peak in the amplified cellular sequence corresponds to an epithelial-cell-type specific enhancer. Thus, HPV16 integration generated a super-enhancer-like element composed of tandem interspersed copies of the viral upstream regulatory region and a cellular enhancer, to drive high levels of oncogene expression. PMID:29364907

Identification of Novel Ovarian Cancer Oncogenes that Function by Regulating Exosome Function

Science.gov (United States)

2017-09-01

Novel Ovarian Cancer Oncogenes that Function by Regulating Exosome Function September 2017 x 1Sep2016...31Aug2017 Email: mbirrer@partners.org 6 Identification of Novel Ovarian Cancer Oncogenes that Function by Regulating Exosome Function xx

Retrospective analysis of oncogenic human papilloma virus and Epstein-Barr virus prevalence in Turkish nasopharyngeal cancer patients.

Science.gov (United States)

Tatlı Doğan, Hayriye; Kılıçarslan, Aydan; Doğan, Mehmet; Süngü, Nuran; Güler Tezel, Gaye; Güler, Gülnur

2016-11-01

Nasopharyngeal carcinoma (NPC) is associated with the Epstein-Barr virus (EBV). Human papilloma virus (HPV) has also been detected in NPC cases. In this retrospective study, we analyze the frequency of EBV and HPV infection in 82 Turkish patients with NPC. A total of 82 were evaluated for EBV and HPV. In situ hybridization (ISH) was performed for EBV. HPV-ISH and P16 immunohistochemistry used to determine the HPV status. Seventy-two of the 82 (87%) NPC patients were EBV-positive. The highest rate of EBV-positivity was found in undifferentiated NPC patients, which accounted for 65 of 68 (95.6%) undifferentiated cases. One of the 82 NPC patients whose tumor was non-keratinizing differentiated, contained HPV. Our data shows that EBV is closely associated with NPC in Turkey. We found lower rates of HPV-positivity in NPC patients than in North American populations. In addition, both EBV and HPV-negativity were more associated with decreased survival than EBV-positive cases. Copyright © 2016 Elsevier GmbH. All rights reserved.

The Oncogenic Risks of Diagnostic CT Scam Studies in Children

International Nuclear Information System (INIS)

Brent, R.

2004-01-01

Brenner et al (2001) reported that estimates of the exposure to children from CT scans indicates that the exposures are both higher than from conventional radiographic studies and higher than is necessary to obtain quality examinations. utilizing the oncogenic risk data from the RERF study in Japan, Brenner et al estimated that the oncogenic risk in this population of CT exposed children exposed each year would result in an additional 500 cases of cancer. This risk estimate is supported by the RERF epidemiological data obtained from the populations exposed in Hiroshima and Nagasaki. the increased risks associated with the increased exposure from CT scans have raised concern and stimulated discussion. Although there is little doubt about the benefits of CT scans in improving the health care of children, there is concern about the estimated oncogenic risk, especially since the frequency of CT studies has been increasing. Applying the oncogenic risks of ionizing radiation from the RERF data may not be appropriate for all types of radiation exposure for accurately predicting the incidence of cancer in exposed children because of the impact of 1) partial versus whole-body irradiation, and 2) the protraction of the exposure. Other population of children who have been exposed to radiation and whose incidence of cancer has been studied will be presented and those studies indicate that the risk of cancer is much lower or not increased at all with exposures in the diagnostic range. finally, the dramatic impact of the use of CT scans in clinical pediatric practice saves lives and improves diagnostic accuracy. Therefore, it is crucial that a scholarly evaluation of the risks and benefits should be initiated. The radiology community and the manufacturers have already initiated programs to decrease the exposure significantly. But it is essential that well-planned, retrospective and prospective epidemiology studies should be initiated to study the oncogenic risks. If you want to

A view on EGFR-targeted therapies from the oncogene-addiction perspective.

Science.gov (United States)

Perez, Rolando; Crombet, Tania; de Leon, Joel; Moreno, Ernesto

2013-01-01

Tumor cell growth and survival can often be impaired by inactivating a single oncogen- a phenomenon that has been called as "oncogene addiction." It is in such scenarios that molecular targeted therapies may succeed. among known oncogenes, the epidermal growth factor receptor (EGFR) has become the target of different cancer therapies. So far, however, the clinical benefit from EGFR-targeted therapies has been rather limited. a critical review of the large amount of clinical data obtained with anti-EGFR agents, carried out from the perspective of the oncogene addiction concept, may help to understand the causes of the unsatisfactory results. In this article we intend to do such an exercise taking as basis for the analysis a few case studies of anti-EGFR agents that are currently in the clinic. There, the "EGFR addiction" phenomenon becomes apparent in high-responder patients. We further discuss how the concept of oncogene addiction needs to be interpreted on the light of emerging experimental evidences and ideas; in particular, that EGFR addiction may reflect the interconnection of several cellular pathways. In this regard we set forth several hypotheses; namely, that requirement of higher glucose uptake by hypoxic tumor cells may reinforce EGFR addiction; and that chronic use of EGFR-targeted antibodies in EGFR-addicted tumors would induce stable disease by reversing the malignant phenotype of cancer stem cells and also by sustaining an anti-tumor T cell response. Finally, we discuss possible reasons for the failure of certain combinatorial therapies involving anti-EGFR agents, arguing that some of these agents might produce either a negative or a positive trans-modulation effect on other oncogenes. It becomes evident that we need operational definitions of EGFR addiction in order to determine which patient populations may benefit from treatment with anti-EGFR drugs, and to improve the design of these therapies.

A view on EGFR-targeted therapies from the oncogene-addiction perspective

Directory of Open Access Journals (Sweden)

Rolando ePerez

2013-04-01

Full Text Available Tumor cell growth and survival can often be impaired by inactivating a single oncogen – a phenomenon that has been called as 'oncogene addiction'. It is in such scenarios that molecular targeted therapies may succeed. Among known oncogenes, the epidermal growth factor receptor (EGFR has become the target of different cancer therapies. So far, however, the clinical benefit from EGFR-targeted therapies has been rather limited. A critical review of the large amount of clinical data obtained with anti-EGFR agents, carried out from the perspective of the oncogene addiction concept, may help to understand the causes of the unsatisfactory results. In this article we intend to do such an exercise taking as basis for the analysis a few case studies of anti-EGFR agents that are currently in the clinic. There, the 'EGFR addiction' phenomenon becomes apparent in high-responder patients. We further discuss how the concept of oncogene addiction needs to be interpreted on the light of emerging experimental evidences and ideas; in particular, that EGFR addiction may reflect the interconnection of several cellular pathways. In this regard we set forth several hypotheses; namely, that requirement of higher glucose uptake by hypoxic tumor cells may reinforce EGFR addiction; and that chronic use of EGFR-targeted antibodies in EGFR-addicted tumors would induce stable disease by reversing the malignant phenotype of cancer stem cells and also by sustaining an anti-tumor T cell response. Finally, we discuss possible reasons for the failure of certain combinatorial therapies involving anti-EGFR agents, arguing that some of these agents might produce either a negative or a positive trans-modulation effect on other oncogenes. It becomes evident that we need operational definitions of EGFR addiction in order to determine which patient populations may benefit from treatment with anti-EGFR drugs, and to improve the design of these therapies.

Epstein-Barr virus infection and nasopharyngeal carcinoma: the other side of the coin.

Science.gov (United States)

Perri, Francesco; Della Vittoria Scarpati, Giuseppina; Giuliano, Mario; D'Aniello, Carmine; Gnoni, Antonio; Cavaliere, Carla; Licchetta, Antonella; Pisconti, Salvatore

2015-11-01

Oncogenic viruses may have a significant impact on the therapeutic management of several malignancies besides their well-known role in tumor pathogenesis. Epstein-Barr virus (EBV) induces neoplastic transformation of epithelial cells of the nasopharynx by various molecular mechanisms mostly involving activation of oncogenes and inactivation of tumor-suppressor genes. EBV infection can also induce the expression of several immunogenic peptides on the plasma membrane of the infected cells. Importantly, these virus-related antigens may be used as targets for antitumor immunotherapy-based treatment strategies. Two different immunotherapy strategies, namely adoptive and active immunotherapy, have been developed and strongly improved in the recent years. Furthermore, EBV infection may influence the use of targeted therapies for nasopharyngeal carcinoma (NPC) considering that the presence of EBV can induce important modifications in cell signaling. As an example, latent membrane protein type 1 is a viral transmembrane protein mainly involved in the cancerogenesis process, which can also mediate overexpression of the epidermal growth factor receptor (EGFR) in NPC cells, rendering them more sensitive to anti-EGFR therapy. Finally, EBV may induce epigenetic changes in the infected cells, such as DNA hypermethylation and histone deacetylation, that can sustain tumor growth and can thus be considered potential targets for novel therapies. In conclusion, EBV infection can modify important biological features of NPC cells, rendering them more vulnerable to both immunotherapy and targeted therapy.

Molecular biology III - Oncogenes and tumor suppressor genes

International Nuclear Information System (INIS)

Giaccia, Amato J.

1996-01-01

Purpose: The purpose of this course is to introduce to radiation oncologists the basic concepts of tumorigenesis, building on the information that will be presented in the first and second part of this series of lectures. Objective: Our objective is to increase the current understanding of radiation oncologists with the process of tumorigenesis, especially focusing on genes that are altered in many tumor types that are potential candidates for novel molecular strategies. As strategies to treat cancer of cancer are becoming more sophisticated, it will be important for both the practitioner and academician to develop a basic understanding of the function of cancer 'genes'. This will be the third in a series of refresher courses that are meant to address recent advances in Cancer Biology in a way that both clinicians without previous knowledge of molecular biology or experienced researchers will find interesting. The lecture will begin with a basic overview of tumorigenesis; methods of detecting chromosome/DNA alterations, approaches used to isolate oncogenes and tumor suppressor genes, and their role in cell killing by apoptosis. Special attention will be given to oncogenes and tumor suppressor genes that are modulated by ionizing radiation and the tumor microenvironment. We will relate the biology of oncogenes and tumor suppressor genes to basic aspects of radiation biology that would be important in clinical practice. Finally, we will review recent studies on the prognostic significance of p53 mutations and apoptosis in tumor specimens. The main point of this lecture is to relate both researcher and clinician what are the therapeutic ramifications of oncogene and tumor suppressor gene mutations found in human neoptasia

Silencing Agrobacterium oncogenes in transgenic grapevine results in strain-specific crown gall resistance.

Science.gov (United States)

Galambos, A; Zok, A; Kuczmog, A; Oláh, R; Putnoky, P; Ream, W; Szegedi, E

2013-11-01

Grapevine rootstock transformed with an Agrobacterium oncogene-silencing transgene was resistant to certain Agrobacterium strains but sensitive to others. Thus, genetic diversity of Agrobacterium oncogenes may limit engineering crown gall resistance. Crown gall disease of grapevine induced by Agrobacterium vitis or Agrobacterium tumefaciens causes serious economic losses in viticulture. To establish crown gall-resistant lines, somatic proembryos of Vitis berlandieri × V. rupestris cv. 'Richter 110' rootstock were transformed with an oncogene-silencing transgene based on iaaM and ipt oncogene sequences from octopine-type, tumor-inducing (Ti) plasmid pTiA6. Twenty-one transgenic lines were selected, and their transgenic nature was confirmed by polymerase chain reaction (PCR). These lines were inoculated with two A. tumefaciens and three A. vitis strains. Eight lines showed resistance to octopine-type A. tumefaciens A348. Resistance correlated with the expression of the silencing genes. However, oncogene silencing was mostly sequence specific because these lines did not abolish tumorigenesis by A. vitis strains or nopaline-type A. tumefaciens C58.

Retroviruses Hijack Chromatin Loops to Drive Oncogene Expression and Highlight the Chromatin Architecture around Proto-Oncogenic Loci

Science.gov (United States)

Pattison, Jillian M.; Wright, Jason B.; Cole, Michael D.

2015-01-01

The majority of the genome consists of intergenic and non-coding DNA sequences shown to play a major role in different gene regulatory networks. However, the specific potency of these distal elements as well as how these regions exert function across large genomic distances remains unclear. To address these unresolved issues, we closely examined the chromatin architecture around proto-oncogenic loci in the mouse and human genomes to demonstrate a functional role for chromatin looping in distal gene regulation. Using cell culture models, we show that tumorigenic retroviral integration sites within the mouse genome occur near existing large chromatin loops and that this chromatin architecture is maintained within the human genome as well. Significantly, as mutagenesis screens are not feasible in humans, we demonstrate a way to leverage existing screens in mice to identify disease relevant human enhancers and expose novel disease mechanisms. For instance, we characterize the epigenetic landscape upstream of the human Cyclin D1 locus to find multiple distal interactions that contribute to the complex cis-regulation of this cell cycle gene. Furthermore, we characterize a novel distal interaction upstream of the Cyclin D1 gene which provides mechanistic evidence for the abundant overexpression of Cyclin D1 occurring in multiple myeloma cells harboring a pathogenic translocation event. Through use of mapped retroviral integrations and translocation breakpoints, our studies highlight the importance of chromatin looping in oncogene expression, elucidate the epigenetic mechanisms crucial for distal cis-regulation, and in one particular instance, explain how a translocation event drives tumorigenesis through upregulation of a proto-oncogene. PMID:25799187

bcr-abl oncogene activation in Philadelphia chromosome-positive acute lymphoblastic leukemia

NARCIS (Netherlands)

Hermans, A.; Gow, J.; Selleri, L.; von Lindern, M.; Hagemeijer, A.; Wiedemann, L. M.; Grosveld, G.

1988-01-01

Tumor-specific alterations in oncogenes are thought to play a central role in the development of cancer. An example is the consistent fusion of the bcr gene to the c-abl oncogene on the Ph chromosome in CML. The Ph chromosome can also be observed in ALL. About 50% of Ph+ ALL cases, in contrast to

Change of mitotic cycle and DNA repair in embryonic cells of rat, immortalized by E1 A oncogene and transformated by E1 A and c-Ha-Ras oncogenes under ionizing radiation action

International Nuclear Information System (INIS)

Kirillova, T.V.

1997-01-01

Comparison investigation into the repair of mitotic cycle and the reunion of DN single- and double-strand breaks in gamma-ray irradiated initial E1 A oncogene immortalized and E1 A and c-Ha-Ras oncogene transformed (mutant form) lines of rat embryonic fibroblasts was carried out. Possible involvement of Ras gene product in DNA repair speed governing and absence of tumor suppression function of p 53 protein in the embryonic and E1 A oncogene immortalized cells of rat fibroblast, as well as, presence of the mentioned function of p 53 protein in E1 A and c-Ha-Ras oncogene transformed cells were studied [ru

Oncogene expression in primary lung tumors in dogs that inhaled {sup 239}PuO{sub 2}

Energy Technology Data Exchange (ETDEWEB)

Kelly, G; Kerkof, P R; Haley, P J

1988-12-01

Ten radiation-induced and three spontaneous lung tumors were analyzed for aberrant expression of known oncogenes. In 12 of 13 tumors tested, sequences hybridizing to the c-myc oncogene were expressed at levels 1.5 times higher than sequences hybridizing to {beta}-actin. This level of oncogene expression was also observed in 9 of 13 tumors for 1 or more members of the ras family of oncogenes. Seven of thirteen tumors examined express sequences that hybridize with clones of v-ros or c-met. The ros and met clones both code for oncogenes whose normal homologues are transmembrane proteins related to the insulin receptor. (author)

Early bichemical markers of effects: Enzyme induction, oncogene activation and markers of oxidative damage

DEFF Research Database (Denmark)

Poulsen, Henrik E.; Loft, Steffen

1995-01-01

Early bichemical marker, enzyme induction, oncogene activation, oxidative damage, low-density lipoprotein......Early bichemical marker, enzyme induction, oncogene activation, oxidative damage, low-density lipoprotein...

Role of Tax protein in human T-cell leukemia virus type-I leukemogenicity

Directory of Open Access Journals (Sweden)

Aboud Mordechai

2004-08-01

Full Text Available Abstract HTLV-1 is the etiological agent of adult T-cell leukemia (ATL, the neurological syndrome TSP/HAM and certain other clinical disorders. The viral Tax protein is considered to play a central role in the process leading to ATL. Tax modulates the expression of many viral and cellular genes through the CREB/ATF-, SRF- and NF-κB-associated pathways. In addition, Tax employs the CBP/p300 and p/CAF co-activators for implementing the full transcriptional activation competence of each of these pathways. Tax also affects the function of various other regulatory proteins by direct protein-protein interaction. Through these activities Tax sets the infected T-cells into continuous uncontrolled replication and destabilizes their genome by interfering with the function of telomerase and topoisomerase-I and by inhibiting DNA repair. Furthermore, Tax prevents cell cycle arrest and apoptosis that would otherwise be induced by the unrepaired DNA damage and enables, thereby, accumulation of mutations that can contribute to the leukemogenic process. Together, these capacities render Tax highly oncogenic as reflected by its ability to transform rodent fibroblasts and primary human T-cells and to induce tumors in transgenic mice. In this article we discuss these effects of Tax and their apparent contribution to the HTLV-1 associated leukemogenic process. Notably, however, shortly after infection the virus enters into a latent state, in which viral gene expression is low in most of the HTLV-1 carriers' infected T-cells and so is the level of Tax protein, although rare infected cells may still display high viral RNA. This low Tax level is evidently insufficient for exerting its multiple oncogenic effects. Therefore, we propose that the latent virus must be activated, at least temporarily, in order to elevate Tax to its effective level and that during this transient activation state the infected cells may acquire some oncogenic mutations which can enable them to

Role of Tax protein in human T-cell leukemia virus type-I leukemogenicity.

Science.gov (United States)

Azran, Inbal; Schavinsky-Khrapunsky, Yana; Aboud, Mordechai

2004-08-13

HTLV-1 is the etiological agent of adult T-cell leukemia (ATL), the neurological syndrome TSP/HAM and certain other clinical disorders. The viral Tax protein is considered to play a central role in the process leading to ATL. Tax modulates the expression of many viral and cellular genes through the CREB/ATF-, SRF- and NF-kappaB-associated pathways. In addition, Tax employs the CBP/p300 and p/CAF co-activators for implementing the full transcriptional activation competence of each of these pathways. Tax also affects the function of various other regulatory proteins by direct protein-protein interaction. Through these activities Tax sets the infected T-cells into continuous uncontrolled replication and destabilizes their genome by interfering with the function of telomerase and topoisomerase-I and by inhibiting DNA repair. Furthermore, Tax prevents cell cycle arrest and apoptosis that would otherwise be induced by the unrepaired DNA damage and enables, thereby, accumulation of mutations that can contribute to the leukemogenic process. Together, these capacities render Tax highly oncogenic as reflected by its ability to transform rodent fibroblasts and primary human T-cells and to induce tumors in transgenic mice. In this article we discuss these effects of Tax and their apparent contribution to the HTLV-1 associated leukemogenic process. Notably, however, shortly after infection the virus enters into a latent state, in which viral gene expression is low in most of the HTLV-1 carriers' infected T-cells and so is the level of Tax protein, although rare infected cells may still display high viral RNA. This low Tax level is evidently insufficient for exerting its multiple oncogenic effects. Therefore, we propose that the latent virus must be activated, at least temporarily, in order to elevate Tax to its effective level and that during this transient activation state the infected cells may acquire some oncogenic mutations which can enable them to further progress towards

The DNA damage checkpoint precedes activation of ARF in response to escalating oncogenic stress during tumorigenesis

DEFF Research Database (Denmark)

Evangelou, K.; Bartkova, J.; Kotsinas, A.

2013-01-01

oncogenes showed that the delayed upregulation of ARF reflected a requirement for a higher, transcriptionally based threshold of oncogenic stress, elicited by at least two oncogenic 'hits', compared with lower activation threshold for DDR. We propose that relative to DDR activation, ARF provides...

Characterization of TRPS1 and ERAS as oncogenes implicated in breast cancer

Energy Technology Data Exchange (ETDEWEB)

Lopez Gonzalez, L.

2015-07-01

New high throughput technologies have made possible to identify putative oncogenes in breast cancer. In this project we aim to relate and characterise two novel putative oncogenes, ERAS and TRPS1, in their role in human breast cancer. TRPS1, an atypical GATA factor, modulates cell proliferation and controls cell cycle progression through repression of GATA-regulated genes, therefore acting as a tumour suppressor gene. Conversely, TRPS1 expression has been shown to be significantly elevated in luminal and in a lesser extent in basal breast cancer cells, presenting roles both as an oncogene and as a tumour suppressor gene in breast cancer development. The aim of this project is therefore to determine the characteristics of TRPS1 either as a putative novel human oncogene or as a tumour suppressor gene in breast cancer cells. To this aim, we have cloned a novel isoform of TRPS1 and introduced it into several breast cancer cell lines. Our results show that overexpression of this isoform of TRPS1 results in variations in motility in non-carcinogenic cell lines, as well as in a series of EMT-like changes such as the down-regulation of the EMT marker E-cadherin, both of which can be associated to an increase in malignancy, suggesting an oncogenic behaviour for TRPS1. Furthermore, our results suggest that constitutively active members of the RAS protein family induce the expression of TRPS1, establishing a relationship between both genes. We can conclude that the effects of TRPS1 overexpression are moderate, inducing some changes but not fully transforming the cells. Therefore we cannot confirm that TRPS1 is a putative oncogene in breast cancer. (Author)

Poultry Allele-Specific Expression (ASE) of CD4+ T Cells in Response to Marek’s Disease Virus Infection

Science.gov (United States)

Marek’s disease (MD) is a T cell lymphoma disease of poultry induced by Marek’s disease virus (MDV), a highly oncogenic alphaherpesvirus. To identify high-confidence candidate genes of MD genetic resistance, transcriptomic data in CD4+ T cells were obtained from MDV infected and non-infected groups ...

Purified Hexameric Epstein-Barr Virus-Encoded BARF1 Protein for Measuring Anti-BARF1 Antibody Responses in Nasopharyngeal Carcinoma Patients

NARCIS (Netherlands)

Hoebe, E. K.; Hutajulu, S. H.; van Beek, J.; Stevens, S. J.; Paramita, D. K.; Greijer, A. E.; Middeldorp, J. M.

2011-01-01

WHO type III nasopharyngeal carcinoma (NPC) is highly prevalent in Indonesia and 100% associated with Epstein-Barr virus (EBV). NPC tumor cells express viral proteins, including BARF1, which is secreted and is considered to have oncogenic and immune-modulating properties. Recently, we found

Diagnosis of Epstein-Barr Virus Markers and Particles in Generalized Lymphadenopathy in Egyptian Children before and after School Age

International Nuclear Information System (INIS)

Nasr, S.; Ashry, K.; El-Gayar, A.; Zawahry, K.; Mohamed, F.

2005-01-01

Viral Infections are more more likely to cause generalized lymphadenopathy than other type of infections. Epstein-Barr virus (EBV) has been identified as the etiological agent in infectious mononucleosis and has been proved to be an oncogenic virus. It has been reported to be associated with Burkett's lymphoma. The present work aimed at studying the frequency of Epstein-Barr virus in relation to lymphadenopathy in Egyptian children, immunological, ultra-structural and epidemiological studies of Epstein-Barr virus infection in relation to different age groups and sex factors. The study also correlates between diagnostic value of the different serological tests including quality control double study in Cairo and France and hematological finding as well as electron microscopic finding

Using 18F FDG PET/CT to Detect an occult Mesenchymal Tumor Causing Oncogenic Osteomalacia

International Nuclear Information System (INIS)

Seo, Hyo Jung; Choi, Yun Jung; Kim, Hyun Jeong; Jeong, Yong Hyu; Cho, Arthur; Lee, Jae Hoon; Yun, Mijin; Lee, Jong Doo; Kang, Won Jun

2011-01-01

Oncogenic osteomalacia is a rare paraneoplastic syndrome characterized by renal phosphate excretion, hypophosphatemia, and osteomalacia. This syndrome is often caused by tumors of mesenchymal origin. Patients with oncogenic osteomalacia have abnormal bone mineralization, resulting in a high frequency of fractures. Tumor resection is the treatment of choice, as it will often correct the metabolic imbalance. Although oncogenic osteomalacia is a potentially curable disease, diagnosis is difficult and often delayed because of the small size and sporadic location of the tumor. Bone scintigraphy and radiography best characterize osteoma lacia; magnetic resonance imaging findings are nonspecific. Here, we report a case of oncogenic osteomalacia secondary to a phosphaturic mesenchymal tumor that was successfully detected by 18F fluorodeoxyglucose positron emission tomography/computed tomography ( 18F FDG PET/CT). This case illustrates the advantages of 18F FDG PET/CT in detecting the occult mesenchymal tumor that causes oncogenic osteomalacia.

Exosomes facilitate therapeutic targeting of oncogenic KRAS in pancreatic cancer.

Science.gov (United States)

Kamerkar, Sushrut; LeBleu, Valerie S; Sugimoto, Hikaru; Yang, Sujuan; Ruivo, Carolina F; Melo, Sonia A; Lee, J Jack; Kalluri, Raghu

2017-06-22

The mutant form of the GTPase KRAS is a key driver of pancreatic cancer but remains a challenging therapeutic target. Exosomes are extracellular vesicles generated by all cells, and are naturally present in the blood. Here we show that enhanced retention of exosomes, compared to liposomes, in the circulation of mice is likely due to CD47-mediated protection of exosomes from phagocytosis by monocytes and macrophages. Exosomes derived from normal fibroblast-like mesenchymal cells were engineered to carry short interfering RNA or short hairpin RNA specific to oncogenic Kras G12D , a common mutation in pancreatic cancer. Compared to liposomes, the engineered exosomes (known as iExosomes) target oncogenic KRAS with an enhanced efficacy that is dependent on CD47, and is facilitated by macropinocytosis. Treatment with iExosomes suppressed cancer in multiple mouse models of pancreatic cancer and significantly increased overall survival. Our results demonstrate an approach for direct and specific targeting of oncogenic KRAS in tumours using iExosomes.

Cellular oncogene expression following exposure of mice to γ-rays

International Nuclear Information System (INIS)

Anderson, A.; Woloschak, G.E.

1991-01-01

We examined the effects of total body exposure of BCF1 mice to γ-rays (300 cGy) in modulating expression of cellular oncogenes in both gut and liver tissues. We selected specific cellular oncogenes (c-fos, c-myc, c-src, and c-H-ras), based on their normal expression in liver and gut tissues from untreated mice. As early as 5 min. following whole body exposure of BCF1 mice to γ-rays we detected induction of mRNA specific for c-src and c-H-ras in both liver and gut tissues. c-fos RNA was slightly decreased in accumulation in gut but was unaffected in liver tissue from irradiated mice relative to untreated controls. c-myc mRNA accumulation was unaffected in all tissues examined. These experiments document that modulation of cellular oncogene expression can occur as an early event in tissues following irradiation and suggest that this modulation may play a role in radiation-induced carcinogenesis

Construction of rat cell lines that contain potential morphologically transforming regions of the herpes simplex virus type 2 genome

NARCIS (Netherlands)

van den Berg, F. M.; van Amstel, P. J.; Walboomers, J. M.

1985-01-01

Hybrid recombinant plasmids were constructed; they were composed of the herpes simplex virus type 2 (HSV2) thymidine kinase (tk) gene and DNA sequences of HSV2 that have been reported to induce morphological and/or oncogenic transformation of rodent cells in culture. Several plasmids were made in

One lesion, one virus: individual components of high-grade anal intraepithelial neoplasia in HIV-positive men contain a single HPV type

NARCIS (Netherlands)

Richel, Olivier; Quint, Koen D.; Lindeman, Jan; van Noesel, Carel J. M.; de Koning, Maurits N. C.; van den Munckhof, Henk A. M.; de Vries, Henry J. C.; Prins, Jan M.; Quint, Wim G. V.

2014-01-01

High-grade anal intraepithelial neoplasia (AIN) is present in many human immunodeficiency virus (HIV)-positive men who have sex with men. The major etiologic factor is infection with an oncogenic human papillomavirus (HPV) genotype. We investigated whether individual components of high-grade AIN are

Intracortical osteoblastic osteosarcoma with oncogenic rickets

International Nuclear Information System (INIS)

Hasegawa, T.; Hirohashi, Setsuo; Shimoda, Tadakazu; Yokoyama, Ryohei; Beppu, Yasuo; Maeda, Shotaro

1999-01-01

Intracortical osteosarcoma is the rarest variant of osteosarcoma, occurring within, and usually confined to, the cortical bone. Oncogenic osteomalacia, or rickets, is an unusual clinicopathologic entity in which vitamin D-resistant osteomalacia, or rickets, occurs in association with some tumors of soft tissue or bone. We present a case of oncogenic rickets associated with intracortical osteosarcoma of the tibia in a 9-year-old boy, whose roentgenographic abnormalities of rickets disappeared and pertinent laboratory data except for serum alkaline phosphatase became normal after surgical resection of the tumor. Histologically, the tumor was an osteosarcoma with a prominent osteoblastic pattern. An unusual microscopic feature was the presence of matrix mineralization showing rounded calcified structures (calcified spherules). Benign osteoblastic tumors, such as osteoid osteoma and osteoblastoma, must be considered in the differential diagnosis because of the relatively low cellular atypia and mitotic activity of this tumor. The infiltrating pattern with destruction or engulfment of normal bone is a major clue to the correct diagnosis of intracortical osteosarcoma. The co-existing radiographic changes of rickets were due to the intracortical osteosarcoma. (orig.)

Novel Combinatorial Chemistry-Derived Inhibitors of Oncogenic Phosphatases

National Research Council Canada - National Science Library

Lazo, John

1999-01-01

Our overall goal of this US Army Breast Cancer Grant entitled "Novel Combinatorial Chemistry-Derived Inhibitors of Oncogenic Phosphatases" is to identity and develop novel therapeutic agents for human breast cancer...

Activation of oncogenes by radon progeny and x-rays

Energy Technology Data Exchange (ETDEWEB)

Ling, C.C.

1990-01-01

The overall goal of this proposal is to study the carcinogenic effect of both high and low LET radiation at the molecular level, utilizing techniques developed in molecular biology, cancer cell biology and radiation biology. The underlying assumption is that malignant transformation of normal cells is a multistep process requiring two or more molecular events in the genomic DNA. We hypothesize that radiation may induce such events in one or more steps of the multistep process. We will use in vitro models of transformation that reproduce the stepwise progression of normal cells toward the transformed phenotype and ask whether radiation can provide the necessary activating function at discrete steps along this path. Our strategy involves transfecting into normal primary cells a variety of cloned oncogenes that are known to supply only some of the functions necessary for full transformation. These partially transformed'' cells will be the targets for irradiation by x-rays and alpha particles. The results will provide the basis for assessing the ability of ionizing radiation to activate oncogenic functions that complement'' the oncogene already present in the transfected cells and produce the fully transformed phenotype. Progress is described. 121 refs.

Activation of oncogenes by radon progeny and x-rays

International Nuclear Information System (INIS)

Ling, C.C.

1990-01-01

The overall goal of this proposal is to study the carcinogenic effect of both high and low LET radiation at the molecular level, utilizing techniques developed in molecular biology, cancer cell biology and radiation biology. The underlying assumption is that malignant transformation of normal cells is a multistep process requiring two or more molecular events in the genomic DNA. We hypothesize that radiation may induce such events in one or more steps of the multistep process. We will use in vitro models of transformation that reproduce the stepwise progression of normal cells toward the transformed phenotype and ask whether radiation can provide the necessary activating function at discrete steps along this path. Our strategy involves transfecting into normal primary cells a variety of cloned oncogenes that are known to supply only some of the functions necessary for full transformation. These ''partially transformed'' cells will be the targets for irradiation by x-rays and alpha particles. The results will provide the basis for assessing the ability of ionizing radiation to activate oncogenic functions that ''complement'' the oncogene already present in the transfected cells and produce the fully transformed phenotype. Progress is described. 121 refs

Shared Oncogenic Pathways Implicated in Both Virus-Positive and UV-Induced Merkel Cell Carcinomas.

Science.gov (United States)

González-Vela, María Del Carmen; Curiel-Olmo, Soraya; Derdak, Sophia; Beltran, Sergi; Santibañez, Miguel; Martínez, Nerea; Castillo-Trujillo, Alfredo; Gut, Martha; Sánchez-Pacheco, Roxana; Almaraz, Carmen; Cereceda, Laura; Llombart, Beatriz; Agraz-Doblas, Antonio; Revert-Arce, José; López Guerrero, José Antonio; Mollejo, Manuela; Marrón, Pablo Isidro; Ortiz-Romero, Pablo; Fernandez-Cuesta, Lynnette; Varela, Ignacio; Gut, Ivo; Cerroni, Lorenzo; Piris, Miguel Ángel; Vaqué, José Pedro

2017-01-01

Merkel cell carcinoma (MCC) is a highly malignant neuroendocrine tumor of the skin whose molecular pathogenesis is not completely understood, despite the role that Merkel cell polyomavirus can play in 55-90% of cases. To study potential mechanisms driving this disease in clinically characterized cases, we searched for somatic mutations using whole-exome sequencing, and extrapolated our findings to study functional biomarkers reporting on the activity of the mutated pathways. Confirming previous results, Merkel cell polyomavirus-negative tumors had higher mutational loads with UV signatures and more frequent mutations in TP53 and RB compared with their Merkel cell polyomavirus-positive counterparts. Despite important genetic differences, the two Merkel cell carcinoma etiologies both exhibited nuclear accumulation of oncogenic transcription factors such as NFAT or nuclear factor of activated T cells (NFAT), P-CREB, and P-STAT3, indicating commonly deregulated pathogenic mechanisms with the potential to serve as targets for therapy. A multivariable analysis identified phosphorylated CRE-binding protein as an independent survival factor with respect to clinical variables and Merkel cell polyomavirus status in our cohort of Merkel cell carcinoma patients. Copyright © 2016 The Authors. Published by Elsevier Inc. All rights reserved.

Human microRNA oncogenes and tumor suppressors show significantly different biological patterns: from functions to targets.

Directory of Open Access Journals (Sweden)

Dong Wang

Full Text Available MicroRNAs (miRNAs are small noncoding RNAs which play essential roles in many important biological processes. Therefore, their dysfunction is associated with a variety of human diseases, including cancer. Increasing evidence shows that miRNAs can act as oncogenes or tumor suppressors, and although there is great interest in research into these cancer-associated miRNAs, little is known about them. In this study, we performed a comprehensive analysis of putative human miRNA oncogenes and tumor suppressors. We found that miRNA oncogenes and tumor suppressors clearly show different patterns in function, evolutionary rate, expression, chromosome distribution, molecule size, free energy, transcription factors, and targets. For example, miRNA oncogenes are located mainly in the amplified regions in human cancers, whereas miRNA tumor suppressors are located mainly in the deleted regions. miRNA oncogenes tend to cleave target mRNAs more frequently than miRNA tumor suppressors. These results indicate that these two types of cancer-associated miRNAs play different roles in cancer formation and development. Moreover, the patterns identified here can discriminate novel miRNA oncogenes and tumor suppressors with a high degree of accuracy. This study represents the first large-scale bioinformatic analysis of human miRNA oncogenes and tumor suppressors. Our findings provide help for not only understanding of miRNAs in cancer but also for the specific identification of novel miRNAs as miRNA oncogenes and tumor suppressors. In addition, the data presented in this study will be valuable for the study of both miRNAs and cancer.

Repression of transcription mediated at a thyroid hormone response element by the v-erb-A oncogene product

DEFF Research Database (Denmark)

Sap, J; Muñoz, A; Schmitt, J

1989-01-01

Several recent observations, such as the identification of the cellular homologue of the v-erb-A oncogene as a thyroid-hormone receptor, have strongly implicated nuclear oncogenes in transcriptional control mechanisms. The v-erb-A oncogene blocks the differentiation of erythroid cells, and changes...

Tc-99m-HYNIC-TOC SPECT/CT in Oncogenic Osteomalacia

International Nuclear Information System (INIS)

Pusuwan, Pawana; Sriwijitkamol, Apiradee; Muangsomboon, Kobkun; Jantanayingyong, Jantanaras; Muangsomboon, Soranart; Poramatikul, Nipavan

2009-07-01

Full text: Oncogenic osteomalacia is a rare condition characterized by progressive bone pain, muscle weakness and multiple biochemical abnormalities such as hypophosphataemia, hyper phosphaturia and elevated serum alkaline phosphatase. The cause of this syndrome is most commonly from a benign mesenchymal tumor. The tumor is usually small and difficult to localize. We report two patients with oncogenic osteomalacia diagnosed and localized of the tumors by Tc-99m HYNIC-TOC SPECT/CT imaging. The tumors were localized at right thigh and right inguinal region. Tumor removal was successfully done

Links between human LINE-1 retrotransposons and hepatitis virus-related hepatocellular carcinoma

Science.gov (United States)

Honda, Tomoyuki

2016-05-01

Hepatocellular carcinoma (HCC) accounts for approximately 80% of liver cancers, the third most frequent cause of cancer mortality. The most prevalent risk factors for HCC are infections by hepatitis B or hepatitis C virus. Findings suggest that hepatitis virus-related HCC might be a cancer in which LINE-1 retrotransposons, often termed L1, activity plays a potential role. Firstly, hepatitis viruses can suppress host defense factors that also control L1 mobilization. Secondly, many recent studies also have indicated that hypomethylation of L1 affects the prognosis of HCC patients. Thirdly, endogenous L1 retrotransposition was demonstrated to activate oncogenic pathways in HCC. Fourthly, several L1 chimeric transcripts with host or viral genes are found in hepatitis virus-related HCC. Such lines of evidence suggest a linkage between L1 retrotransposons and hepatitis virus-related HCC. Here, I briefly summarize current understandings of the association between hepatitis virus-related HCC and L1. Then, I discuss potential mechanisms of how hepatitis viruses drive the development of HCC via L1 retrotransposons. An increased understanding of the contribution of L1 to hepatitis virus-related HCC may provide unique insights related to the development of novel therapeutics for this disease.

The Leukemic Stem Cell Niche: Adaptation to “Hypoxia” versus Oncogene Addiction

Directory of Open Access Journals (Sweden)

Giulia Cheloni

2017-01-01

Full Text Available Previous studies based on low oxygen concentrations in the incubation atmosphere revealed that metabolic factors govern the maintenance of normal hematopoietic or leukemic stem cells (HSC and LSC. The physiological oxygen concentration in tissues ranges between 0.1 and 5.0%. Stem cell niches (SCN are placed in tissue areas at the lower end of this range (“hypoxic” SCN, to which stem cells are metabolically adapted and where they are selectively hosted. The data reported here indicated that driver oncogenic proteins of several leukemias are suppressed following cell incubation at oxygen concentration compatible with SCN physiology. This suppression is likely to represent a key positive regulator of LSC survival and maintenance (self-renewal within the SCN. On the other hand, LSC committed to differentiation, unable to stand suppression because of addiction to oncogenic signalling, would be unfit to home in SCN. The loss of oncogene addiction in SCN-adapted LSC has a consequence of crucial practical relevance: the refractoriness to inhibitors of the biological activity of oncogenic protein due to the lack of their molecular target. Thus, LSC hosted in SCN are suited to sustain the long-term maintenance of therapy-resistant minimal residual disease.

RASOnD - A comprehensive resource and search tool for RAS superfamily oncogenes from various species

Directory of Open Access Journals (Sweden)

Singh Tej P

2011-07-01

Full Text Available Abstract Background The Ras superfamily plays an important role in the control of cell signalling and division. Mutations in the Ras genes convert them into active oncogenes. The Ras oncogenes form a major thrust of global cancer research as they are involved in the development and progression of tumors. This has resulted in the exponential growth of data on Ras superfamily across different public databases and in literature. However, no dedicated public resource is currently available for data mining and analysis on this family. The present database was developed to facilitate straightforward accession, retrieval and analysis of information available on Ras oncogenes from one particular site. Description We have developed the RAS Oncogene Database (RASOnD as a comprehensive knowledgebase that provides integrated and curated information on a single platform for oncogenes of Ras superfamily. RASOnD encompasses exhaustive genomics and proteomics data existing across diverse publicly accessible databases. This resource presently includes overall 199,046 entries from 101 different species. It provides a search tool to generate information about their nucleotide and amino acid sequences, single nucleotide polymorphisms, chromosome positions, orthologies, motifs, structures, related pathways and associated diseases. We have implemented a number of user-friendly search interfaces and sequence analysis tools. At present the user can (i browse the data (ii search any field through a simple or advance search interface and (iii perform a BLAST search and subsequently CLUSTALW multiple sequence alignment by selecting sequences of Ras oncogenes. The Generic gene browser, GBrowse, JMOL for structural visualization and TREEVIEW for phylograms have been integrated for clear perception of retrieved data. External links to related databases have been included in RASOnD. Conclusions This database is a resource and search tool dedicated to Ras oncogenes. It has

Human Papilloma Virus and Autophagy

Directory of Open Access Journals (Sweden)

Domenico Mattoscio

2018-06-01

Full Text Available Human papilloma viruses (HPVs are a group of double-stranded DNA viruses known to be the primary cause of cervical cancer. In addition, evidence has now established their role in non-melanoma skin cancers, head and neck cancer (HNC, and the development of other anogenital malignancies. The prevalence of HPV-related HNC, in particular oropharyngeal cancers, is rapidly increasing, foreseeing that HPV-positive oropharyngeal cancers will outnumber uterine cervical cancers in the next 15–20 years. Therefore, despite the successful advent of vaccines originally licensed for cervical cancer prevention, HPV burden is still very high, and a better understanding of HPV biology is urgently needed. Autophagy is the physiological cellular route that accounts for removal, degradation, and recycling of damaged organelles, proteins, and lipids in lysosomal vacuoles. In addition to this scavenger function, autophagy plays a fundamental role during viral infections and cancers and is, therefore, frequently exploited by viruses to their own benefit. Recently, a link between HPV and autophagy has clearly emerged, leading to the conceivable development of novel anti-viral strategies aimed at restraining HPV infectivity. Here, recent findings on how oncogenic HPV16 usurp autophagy are described, highlighting similarities and differences with mechanisms adopted by other oncoviruses.

A Novel Role for Keratin 17 in Coordinating Oncogenic Transformation and Cellular Adhesion in Ewing Sarcoma

Science.gov (United States)

Sankar, Savita; Tanner, Jason M.; Bell, Russell; Chaturvedi, Aashi; Randall, R. Lor; Beckerle, Mary C.

2013-01-01

Oncogenic transformation in Ewing sarcoma is caused by EWS/FLI, an aberrant transcription factor fusion oncogene. Glioma-associated oncogene homolog 1 (GLI1) is a critical target gene activated by EWS/FLI, but the mechanism by which GLI1 contributes to the transformed phenotype of Ewing sarcoma was unknown. In this work, we identify keratin 17 (KRT17) as a direct downstream target gene upregulated by GLI1. We demonstrate that KRT17 regulates cellular adhesion by activating AKT/PKB (protein kinase B) signaling. In addition, KRT17 is necessary for oncogenic transformation in Ewing sarcoma and accounts for much of the GLI1-mediated transformation function but via a mechanism independent of AKT signaling. Taken together, our data reveal previously unknown molecular functions for a cytoplasmic intermediate filament protein, KRT17, in coordinating EWS/FLI- and GLI1-mediated oncogenic transformation and cellular adhesion in Ewing sarcoma. PMID:24043308

Using {sup 18F} FDG PET/CT to Detect an occult Mesenchymal Tumor Causing Oncogenic Osteomalacia

Energy Technology Data Exchange (ETDEWEB)

Seo, Hyo Jung; Choi, Yun Jung; Kim, Hyun Jeong; Jeong, Yong Hyu; Cho, Arthur; Lee, Jae Hoon; Yun, Mijin; Lee, Jong Doo; Kang, Won Jun [Yonsei Univ. College of Medicine, Seoul (Korea, Republic of)

2011-09-15

Oncogenic osteomalacia is a rare paraneoplastic syndrome characterized by renal phosphate excretion, hypophosphatemia, and osteomalacia. This syndrome is often caused by tumors of mesenchymal origin. Patients with oncogenic osteomalacia have abnormal bone mineralization, resulting in a high frequency of fractures. Tumor resection is the treatment of choice, as it will often correct the metabolic imbalance. Although oncogenic osteomalacia is a potentially curable disease, diagnosis is difficult and often delayed because of the small size and sporadic location of the tumor. Bone scintigraphy and radiography best characterize osteoma lacia; magnetic resonance imaging findings are nonspecific. Here, we report a case of oncogenic osteomalacia secondary to a phosphaturic mesenchymal tumor that was successfully detected by {sup 18F} fluorodeoxyglucose positron emission tomography/computed tomography ({sup 18F} FDG PET/CT). This case illustrates the advantages of {sup 18F} FDG PET/CT in detecting the occult mesenchymal tumor that causes oncogenic osteomalacia.

Marek’s Disease Virus influences the core gut microbiome of the chicken during the early and late phases of viral replication

Science.gov (United States)

Marek’s disease (MD) is an important neoplastic disease of chickens caused by the Marek’s disease virus (MDV), an oncogenic alphaherpesvirus. In this study, dysbiosis induced by MDV on the core gut flora of chicken was assessed using next generation sequence (NGS) analysis. Total fecal and cecum-der...

Tumor Suppressor p53 Stimulates the Expression of Epstein-Barr Virus Latent Membrane Protein 1.

Science.gov (United States)

Wang, Qianli; Lingel, Amy; Geiser, Vicki; Kwapnoski, Zachary; Zhang, Luwen

2017-10-15

Epstein-Barr virus (EBV) is associated with multiple human malignancies. EBV latent membrane protein 1 (LMP1) is required for the efficient transformation of primary B lymphocytes in vitro and possibly in vivo The tumor suppressor p53 plays a seminal role in cancer development. In some EBV-associated cancers, p53 tends to be wild type and overly expressed; however, the effects of p53 on LMP1 expression is not clear. We find LMP1 expression to be associated with p53 expression in EBV-transformed cells under physiological and DNA damaging conditions. DNA damage stimulates LMP1 expression, and p53 is required for the stimulation. Ectopic p53 stimulates endogenous LMP1 expression. Moreover, endogenous LMP1 blocks DNA damage-mediated apoptosis. Regarding the mechanism of p53-mediated LMP1 expression, we find that interferon regulatory factor 5 (IRF5), a direct target of p53, is associated with both p53 and LMP1. IRF5 binds to and activates a LMP1 promoter reporter construct. Ectopic IRF5 increases the expression of LMP1, while knockdown of IRF5 leads to reduction of LMP1. Furthermore, LMP1 blocks IRF5-mediated apoptosis in EBV-infected cells. All of the data suggest that cellular p53 stimulates viral LMP1 expression, and IRF5 may be one of the factors for p53-mediated LMP1 stimulation. LMP1 may subsequently block DNA damage- and IRF5-mediated apoptosis for the benefits of EBV. The mutual regulation between p53 and LMP1 may play an important role in EBV infection and latency and its related cancers. IMPORTANCE The tumor suppressor p53 is a critical cellular protein in response to various stresses and dictates cells for various responses, including apoptosis. This work suggests that an Epstein-Bar virus (EBV) principal viral oncogene is activated by cellular p53. The viral oncogene blocks p53-mediated adverse effects during viral infection and transformation. Therefore, the induction of the viral oncogene by p53 provides a means for the virus to cope with infection and

Intracortical osteoblastic osteosarcoma with oncogenic rickets

Energy Technology Data Exchange (ETDEWEB)

Hasegawa, T.; Hirohashi, Setsuo [Pathology Division, National Cancer Center Research Institute, Tokyo (Japan); Shimoda, Tadakazu [Clinical Laboratory Division, National Cancer Center Hospital, Tokyo (Japan); Yokoyama, Ryohei; Beppu, Yasuo [Orthopedic Division, National Cancer Center Hospital, Tokyo (Japan); Maeda, Shotaro [Department of Pathology, Nippon Medical School Hospital, Tokyo (Japan)

1999-01-01

Intracortical osteosarcoma is the rarest variant of osteosarcoma, occurring within, and usually confined to, the cortical bone. Oncogenic osteomalacia, or rickets, is an unusual clinicopathologic entity in which vitamin D-resistant osteomalacia, or rickets, occurs in association with some tumors of soft tissue or bone. We present a case of oncogenic rickets associated with intracortical osteosarcoma of the tibia in a 9-year-old boy, whose roentgenographic abnormalities of rickets disappeared and pertinent laboratory data except for serum alkaline phosphatase became normal after surgical resection of the tumor. Histologically, the tumor was an osteosarcoma with a prominent osteoblastic pattern. An unusual microscopic feature was the presence of matrix mineralization showing rounded calcified structures (calcified spherules). Benign osteoblastic tumors, such as osteoid osteoma and osteoblastoma, must be considered in the differential diagnosis because of the relatively low cellular atypia and mitotic activity of this tumor. The infiltrating pattern with destruction or engulfment of normal bone is a major clue to the correct diagnosis of intracortical osteosarcoma. The co-existing radiographic changes of rickets were due to the intracortical osteosarcoma. (orig.) With 8 figs., 25 refs.

Scintigraphic imaging of oncogenes with antisense probes: does it make sense?

International Nuclear Information System (INIS)

Urbain, J.L.C.; Shore, S.K.; Vekemans, M.C.; Cosenza, S.C.; DeRiel, K.; Patel, G.V.; Charkes, N.D.; Malmud, L.S.; Reddy, E.P.

1995-01-01

The aim of this study was to demonstrate that cells which are expressing a particular mRNA transcript do preferentially and specifically retain the antisense probe targeting that mRNA. Using a mouse plasmacytoma cell line (MOPC315) which produces high levels of IgA heavy chain mRNA, a control mouse pre B cell line (7OZ/3B), a human mammary cell line (MCF7) which expresses the erbB2 or neu oncogene, MOPC315 cells as neu-negative controls, and antisense DNA oligonucleotides complementary to the 5' region of the mRNAs and the sense sequence, we have shown that there is a preferential, specific retention of the IgA and neu antisense sequence in MOPC315 and MCF7 cells, respectively. We have further demonstrated that this retention is time and concentration dependent with a maximum at 24 h. We conclude that cancer cells which express a particular oncogene are suitable targets for radiolabeled antisense deoxyoligonucleotides directed toward the oncogene transcript. (orig.)

[Inheritable phenotypic normalization of rodent cells transformed by simian adenovirus SA7 E1 oncogenes by singled-stranded oligonucleotides complementary to a long region of integrated oncogenes].

Science.gov (United States)

Grineva, N I; Borovkova, T V; Sats, N V; Kurabekova, R M; Rozhitskaia, O S; Solov'ev, G Ia; Pantin, V I

1995-08-01

G11 mouse cells and SH2 rat cells transformed with simian adenovirus SA7 DNA showed inheritable oncogen-specific phenotypic normalization when treated with sense and antisense oligonucleotides complementary to long RNA sequences, plus or minus strands of the integrated adenovirus oncogenes E1A and E1B. Transitory treatment of the cells with the oligonucleotides in the absence of serum was shown to cause the appearance of normalized cell lines with fibroblastlike morphology, slower cell proliferation, and lack of ability to form colonies in soft agar. Proliferative activity and adhesion of the normalized cells that established cell lines were found to depend on the concentration of growth factors in the cultural medium. In some of the cell lines, an inhibition of transcription of the E1 oncogenes was observed. The normalization also produced cells that divided 2 - 5 times and died and cells that reverted to a transformed phenotype in 2 - 10 days. The latter appeared predominantly upon the action of the antisense oligonucleotides.

Differential p53 engagement in response to oxidative and oncogenic stresses in Fanconi anemia mice

Science.gov (United States)

Rani, Reena; Li, Jie; Pang, Qishen

2008-01-01

Members of the Fanconi anemia (FA) protein family are involved in repair of genetic damage caused by DNA cross-linkers. It is not clear whether the FA proteins function in oxidative DNA damage and oncogenic stress response. Here we report that deficiency in the Fanca gene in mice elicits a p53-dependent growth arrest and DNA damage response to oxidative DNA damage and oncogenic stress. Using a Fanca-/- Trp53-/- double knockout model and a functionally switchable p53 retrovirus, we define the kinetics, dependence, and persistence of p53-mediated response to oxidative and oncogenic stresses in Fanca-/- cells. Notably, oxidative stress induces persistent p53 response in Fanca-/- cells, likely due to accumulation of unrepaired DNA damage. On the other hand, whereas WT cells exhibit prolonged response to oncogene activation, the p53-activating signals induced by oncogenic ras are short-lived in Fanca-/- cells, suggesting that Fanca may be required for the cell to engage p53 during constitutive ras activation. We propose that the FA proteins protect cells from stress-induced proliferative arrest and tumor evolution by acting as a modulator of the signaling pathways that link FA to p53. PMID:19047147

Differential p53 engagement in response to oxidative and oncogenic stresses in Fanconi anemia mice.

Science.gov (United States)

Rani, Reena; Li, Jie; Pang, Qishen

2008-12-01

Members of the Fanconi anemia (FA) protein family are involved in repair of genetic damage caused by DNA cross-linkers. It is not clear whether the FA proteins function in oxidative DNA damage and oncogenic stress response. Here, we report that deficiency in the Fanca gene in mice elicits a p53-dependent growth arrest and DNA damage response to oxidative DNA damage and oncogenic stress. Using a Fanca-/-Trp53-/- double knockout model and a functionally switchable p53 retrovirus, we define the kinetics, dependence, and persistence of p53-mediated response to oxidative and oncogenic stresses in Fanca-/- cells. Notably, oxidative stress induces persistent p53 response in Fanca-/- cells, likely due to accumulation of unrepaired DNA damage. On the other hand, whereas wild-type cells exhibit prolonged response to oncogene activation, the p53-activating signals induced by oncogenic ras are short-lived in Fanca-/- cells, suggesting that Fanca may be required for the cell to engage p53 during constitutive ras activation. We propose that the FA proteins protect cells from stress-induced proliferative arrest and tumor evolution by acting as a modulator of the signaling pathways that link FA to p53.

Activation of human immunodeficiency virus by ultraviolet radiation

International Nuclear Information System (INIS)

Zmudzka, B.Z.; Beer, J.Z.

1990-01-01

This article reviews the current status of knowledge about UV-induced HIV activation. A brief description of HIV structure and, in particular, its gene promoter is given. The effects of UVR exposure of cells on HIV activation and HIV promoter induction will be reviewed. Some events that follow production of DNA damage and lead, via activation of an oncogene, to HIV promoter induction will be discussed. Possible consequences of promoter induction and HIV activation for the cell and the virus are mentioned. The review concludes with a discussion of practical aspects and perspectives in this research area. (author)

Mechanism of infectivity of a murine leukemia virus in adult mice

International Nuclear Information System (INIS)

Levy, R.L.; Barrington, M.H.; Lerner, R.A.; Dixon, F.J.

1976-01-01

Infection of adult BALB/c mice with murine leukemia virus (MuLV) induces typical thymic lymphomas. Expression of virus was measured by using a radioimmunoassay for murine P-30, a virion core protein. Nineteen days after injection of MuLV-S into adult mice, there were 0.3μg P-30/ml of serum. X-irradiation permitted the early expression of high levels of viremia, when given before or after MuLV-S administration, and it also hastened the development of lymphomas. Seventeen to 21 days after injection of MuLV-S into x-irradiated (600 rads) adult mice, there were 2.7 μg of P-30/ml of serum. The virus produced by infected adult mice was infectious and oncogenic when given to newborn mice. Several lines of evidence are presented that suggest the mechanism by which x-irradiation permits early expession of virion proteins and lymphomas is not immunosuppression

The Expression, Purification, and Characterization of a Ras Oncogene (Bras2) in Silkworm (Bombyx mori)

OpenAIRE

Lv, Zhengbing; Wang, Tao; Zhuang, Wenhua; Wang, Dan; Chen, Jian; Nie, Zuoming; Liu, Lili; Zhang, Wenping; Wang, Lisha; Wang, Deming; Wu, Xiangfu; Li, Jun; Qian, Lian; Zhang, Yaozhou

2013-01-01

The Ras oncogene of silkworm pupae (Bras2) may belong to the Ras superfamily. It shares 77% of its amino acid identity with teratocarcinoma oncogene 21 (TC21) related ras viral oncogene homolog-2 (R-Ras2) and possesses an identical core effector region. The mRNA of Bombyx mori Bras2 has 1412 bp. The open reading frame contains 603 bp, which encodes 200 amino acid residues. This recombinant BmBras2 protein was subsequently used as an antigen to raise a rabbit polyclonal antibody. Western blott...

Oncogenic osteomalacia secondary to a hemangiopericytoma of the hip: case report

International Nuclear Information System (INIS)

Baronofsky, S.I.; Kalbhen, C.L.; Demos, T.C.; Sizemore, G.W.

1999-01-01

Osteomalacia is characterized by abnormally increased unmineralized osteoid within the bone matrix. This metabolic bone disease is usually the result of decreased uptake or abnormal metabolism of vitamin D or of renal tubular phosphate loss. Dietary deficiency, malabsorption, cirrhosis, renal tubular acidosis and certain drugs can cause osteomalacia., Oncogenic osteomalacia - osteomalacia secondary to tumours - is rare, and the exact mechanisms by which neoplasms induce osteomalacia are not known. We describe a patient with chronic osteomalacia of unknown origin who was subsequently found to have oncogenic osteomalacia secondary to a hemangiopericytoma of the hip. (author)

Oncogenic osteomalacia secondary to a hemangiopericytoma of the hip: case report

Energy Technology Data Exchange (ETDEWEB)

Baronofsky, S.I.; Kalbhen, C.L.; Demos, T.C.; Sizemore, G.W. [Loyola Univ. Medical Center, Dept. of Medicine, Maywood, IL (United States)

1999-02-01

Osteomalacia is characterized by abnormally increased unmineralized osteoid within the bone matrix. This metabolic bone disease is usually the result of decreased uptake or abnormal metabolism of vitamin D or of renal tubular phosphate loss. Dietary deficiency, malabsorption, cirrhosis, renal tubular acidosis and certain drugs can cause osteomalacia., Oncogenic osteomalacia - osteomalacia secondary to tumours - is rare, and the exact mechanisms by which neoplasms induce osteomalacia are not known. We describe a patient with chronic osteomalacia of unknown origin who was subsequently found to have oncogenic osteomalacia secondary to a hemangiopericytoma of the hip. (author)

Human papillomavirus E6/E7 oncogenes promote mouse ear regeneration by increasing the rate of wound re-epithelization and epidermal growth.

Science.gov (United States)

Valencia, Concepción; Bonilla-Delgado, José; Oktaba, Katarzyna; Ocádiz-Delgado, Rodolfo; Gariglio, Patricio; Covarrubias, Luis

2008-12-01

Mammals have limited regeneration capacity. We report here that, in transgenic mice (Tg(bK6-E6/E7)), the expression of the E6/E7 oncogenes of human papilloma virus type 16 (HPV16) under the control of the bovine keratin 6 promoter markedly improves the mouse's capacity to repair portions of the ear after being wounded. Increased repair capacity correlates with an increased number of epidermal proliferating cells. In concordance with the expected effects of the E6 and E7 oncogenes, levels of p53 decreased and those of p16 in epidermal cells increased. In addition, we observed that wound re-epithelization proceeded faster in transgenic than in wild-type animals. After the initial re-epithelization, epidermal cell migration from the intact surrounding tissue appears to be a major contributor to the growing epidermis, especially in the repairing tissue of transgenic mice. We also found that there is a significantly higher number of putative epidermal stem cells in Tg(bK6-E6/E7) than in wild-type mice. Remarkably, hair follicles and cartilage regenerated within the repaired ear tissue, without evidence of tumor formation. We propose that the ability to regenerate ear portions is limited by the capacity of the epidermis to repair itself and grow.

p53-independent upregulation of miR-34a during oncogene-induced senescence represses MYC

DEFF Research Database (Denmark)

Christoffersen, N R; Shalgi, R; Frankel, L B

2010-01-01

Aberrant oncogene activation induces cellular senescence, an irreversible growth arrest that acts as a barrier against tumorigenesis. To identify microRNAs (miRNAs) involved in oncogene-induced senescence, we examined the expression of miRNAs in primary human TIG3 fibroblasts after constitutive...

Decomposing Oncogenic Transcriptional Signatures to Generate Maps of Divergent Cellular States.

Science.gov (United States)

Kim, Jong Wook; Abudayyeh, Omar O; Yeerna, Huwate; Yeang, Chen-Hsiang; Stewart, Michelle; Jenkins, Russell W; Kitajima, Shunsuke; Konieczkowski, David J; Medetgul-Ernar, Kate; Cavazos, Taylor; Mah, Clarence; Ting, Stephanie; Van Allen, Eliezer M; Cohen, Ofir; Mcdermott, John; Damato, Emily; Aguirre, Andrew J; Liang, Jonathan; Liberzon, Arthur; Alexe, Gabriella; Doench, John; Ghandi, Mahmoud; Vazquez, Francisca; Weir, Barbara A; Tsherniak, Aviad; Subramanian, Aravind; Meneses-Cime, Karina; Park, Jason; Clemons, Paul; Garraway, Levi A; Thomas, David; Boehm, Jesse S; Barbie, David A; Hahn, William C; Mesirov, Jill P; Tamayo, Pablo

2017-08-23

The systematic sequencing of the cancer genome has led to the identification of numerous genetic alterations in cancer. However, a deeper understanding of the functional consequences of these alterations is necessary to guide appropriate therapeutic strategies. Here, we describe Onco-GPS (OncoGenic Positioning System), a data-driven analysis framework to organize individual tumor samples with shared oncogenic alterations onto a reference map defined by their underlying cellular states. We applied the methodology to the RAS pathway and identified nine distinct components that reflect transcriptional activities downstream of RAS and defined several functional states associated with patterns of transcriptional component activation that associates with genomic hallmarks and response to genetic and pharmacological perturbations. These results show that the Onco-GPS is an effective approach to explore the complex landscape of oncogenic cellular states across cancers, and an analytic framework to summarize knowledge, establish relationships, and generate more effective disease models for research or as part of individualized precision medicine paradigms. Copyright © 2017 Elsevier Inc. All rights reserved.

Development of Novel Therapeutic Agents by Inhibition of Oncogenic MicroRNAs

Directory of Open Access Journals (Sweden)

Dinh-Duc Nguyen

2017-12-01

Full Text Available MicroRNAs (miRs, miRNAs are regulatory small noncoding RNAs, with their roles already confirmed to be important for post-transcriptional regulation of gene expression affecting cell physiology and disease development. Upregulation of a cancer-causing miRNA, known as oncogenic miRNA, has been found in many types of cancers and, therefore, represents a potential new class of targets for therapeutic inhibition. Several strategies have been developed in recent years to inhibit oncogenic miRNAs. Among them is a direct approach that targets mature oncogenic miRNA with an antisense sequence known as antimiR, which could be an oligonucleotide or miRNA sponge. In contrast, an indirect approach is to block the biogenesis of miRNA by genome editing using the CRISPR/Cas9 system or a small molecule inhibitor. The development of these inhibitors is straightforward but involves significant scientific and therapeutic challenges that need to be resolved. In this review, we summarize recent relevant studies on the development of miRNA inhibitors against cancer.

An Anti-Oncogenic Role for Decorin in Mammary Carcinoma

National Research Council Canada - National Science Library

Iozzo, Renato V

2004-01-01

.... In the preliminary data that support the basis of this proposal, we discovered that decorin causes a functional inactivation of the oncogenic ErbB2 protein in mammary carcinoma cells overexpressing ErbB2...

Mutations that abrogate transactivational activity of the feline leukemia virus long terminal repeat do not affect virus replication

International Nuclear Information System (INIS)

Abujamra, Ana L.; Faller, Douglas V.; Ghosh, Sajal K.

2003-01-01

The U3 region of the LTR of oncogenic Moloney murine leukemia virus (Mo-MuLV) and feline leukemia viruses (FeLV) have been previously reported to activate expression of specific cellular genes in trans, such as MHC class I, collagenase IV, and MCP-1, in an integration-independent manner. It has been suggested that transactivation of these specific cellular genes by leukemia virus U3-LTR may contribute to the multistage process of leukemogenesis. The U3-LTR region, necessary for gene transactivational activity, also contains multiple transcription factor-binding sites that are essential for normal virus replication. To dissect the promoter activity and the gene transactivational activity of the U3-LTR, we conducted mutational analysis of the U3-LTR region of FeLV-A molecular clone 61E. We identified minimal nucleotide substitution mutants on the U3 LTR that did not disturb transcription factor-binding sites but abrogated its ability to transactivate the collagenase gene promoter. To determine if these mutations actually have altered any uncharacterized important transcription factor-binding site, we introduced these U3-LTR mutations into the full-length infectious molecular clone 61E. We demonstrate that the mutant virus was replication competent but could not transactivate cellular gene expression. These results thus suggest that the gene transactivational activity is a distinct property of the LTR and possibly not related to its promoter activity. The cellular gene transactivational activity-deficient mutant FeLV generated in this study may also serve as a valuable reagent for testing the biological significance of LTR-mediated cellular gene activation in the tumorigenesis caused by leukemia viruses

Large-scale analysis of protein expression changes in human keratinocytes immortalized by human papilloma virus type 16 E6 and E7 oncogenes

Directory of Open Access Journals (Sweden)

Arnouk Hilal

2009-08-01

Full Text Available Abstract Background Infection with high-risk type human papilloma viruses (HPVs is associated with cervical carcinomas and with a subset of head and neck squamous cell carcinomas. Viral E6 and E7 oncogenes cooperate to achieve cell immortalization by a mechanism that is not yet fully understood. Here, human keratinocytes were immortalized by long-term expression of HPV type 16 E6 or E7 oncoproteins, or both. Proteomic profiling was used to compare expression levels for 741 discrete protein features. Results Six replicate measurements were performed for each group using two-dimensional difference gel electrophoresis (2D-DIGE. The median within-group coefficient of variation was 19–21%. Significance of between-group differences was tested based on Significance Analysis of Microarray and fold change. Expression of 170 (23% of the protein features changed significantly in immortalized cells compared to primary keratinocytes. Most of these changes were qualitatively similar in cells immortalized by E6, E7, or E6/7 expression, indicating convergence on a common phenotype, but fifteen proteins (~2% were outliers in this regulatory pattern. Ten demonstrated opposite regulation in E6- and E7-expressing cells, including the cell cycle regulator p16INK4a; the carbohydrate binding protein Galectin-7; two differentially migrating forms of the intermediate filament protein Cytokeratin-7; HSPA1A (Hsp70-1; and five unidentified proteins. Five others had a pattern of expression that suggested cooperativity between the co-expressed oncoproteins. Two of these were identified as forms of the small heat shock protein HSPB1 (Hsp27. Conclusion This large-scale analysis provides a framework for understanding the cooperation between E6 and E7 oncoproteins in HPV-driven carcinogenesis.

CARCINOMA OF THE LARYNX AND HUMAN PAPILLOMA VIRUS INFECTION

Directory of Open Access Journals (Sweden)

Georgi N. Nikolov

2016-03-01

Full Text Available Background: Laryngeal carcinoma is one of the most common form of head and neck cancer. During the last two decades, it has been recognized that this cancer is causally related to human papillomavirus (HPV. Objective: We presented a study on prevalence of human papilloma viruses (HPV in patients with laryngeal carcinoma. Methods: This study consists of 43 patients with laryngeal carcinoma who were diagnosed and treated with surgical techniques in Department of Otorhinolaryngology, University Hospital, Pleven, Bulgaria. Immunohistochemistry of p16INK4a and Ki-67 were used to prove the relationship between high-risk-HPV (HR-HPV and carcinogenesis. Results: Papilloma virus infection with high-risk oncogenic types of HPV was determined in more than 39.5% of surgically treated patients with histologically proven laryngeal cancer. HPV-induced carcinogenesis was assumed in 17 (13.9% of all patients whose spouses were operated from cervical cancer. The patients with HPV-positive laryngeal carcinoma were younger than the others in the group (8 years on average. Risk factors for development of HPV-associated laryngeal carcinoma were related to higher number of sexual partners and the practice of oral sex. Frequently, in patients with HPV-associated laryngeal carcinoma we find data for so-called “family’s carcinogenesis”. The possibility of appearance (either preceding or following the treatment of a second carcinoma and/or tumour recurrence is higher in HPV-positive laryngeal carcinomas. Conclusion: It is recommended to extend the diagnostic methods for laryngeal and hypo pharyngeal cancer with a routine search for high-risk oncogenic HPV strains.

Induction of non-apoptotic programmed cell death by oncogenic RAS in human epithelial cells and its suppression by MYC overexpression.

Science.gov (United States)

Dendo, Kasumi; Yugawa, Takashi; Nakahara, Tomomi; Ohno, Shin-Ichi; Goshima, Naoki; Arakawa, Hirofumi; Kiyono, Tohru

2018-02-09

Oncogenic mutations of RAS genes, found in about 30% of human cancers, are considered to play important roles in cancer development. However, oncogenic RAS can also induce senescence in mouse and human normal fibroblasts. In some cell lines, oncogenic RAS has been reported to induce non-apoptotic programed cell death (PCD). Here, we investigated effects of oncogenic RAS expression in several types of normal human epithelial cells. Oncogenic RAS but not wild-type RAS stimulated macropinocytosis with accumulation of large-phase lucent vacuoles in the cytoplasm, subsequently leading to cell death which was indistinguishable from a recently proposed new type of PCD, methuosis. A RAC1 inhibitor suppressed accumulation of macropinosomes and overexpression of MYC attenuated oncogenic RAS-induced such accumulation, cell cycle arrest and cell death. MYC suppression or rapamycin treatment in some cancer cell lines harbouring oncogenic mutations in RAS genes induced cell death with accumulation of macropinosomes. These results suggest that this type of non-apoptotic PCD is a tumour-suppressing mechanism acting against oncogenic RAS mutations in normal human epithelial cells, which can be overcome by MYC overexpression, raising the possibility that its induction might be a novel approach to treatment of RAS-mutated human cancers. © The Author(s) 2017. Published by Oxford University Press.

An Interaction with Ewing's Sarcoma Breakpoint Protein EWS Defines a Specific Oncogenic Mechanism of ETS Factors Rearranged in Prostate Cancer.

Science.gov (United States)

Kedage, Vivekananda; Selvaraj, Nagarathinam; Nicholas, Taylor R; Budka, Justin A; Plotnik, Joshua P; Jerde, Travis J; Hollenhorst, Peter C

2016-10-25

More than 50% of prostate tumors have a chromosomal rearrangement resulting in aberrant expression of an oncogenic ETS family transcription factor. However, mechanisms that differentiate the function of oncogenic ETS factors expressed in prostate tumors from non-oncogenic ETS factors expressed in normal prostate are unknown. Here, we find that four oncogenic ETS (ERG, ETV1, ETV4, and ETV5), and no other ETS, interact with the Ewing's sarcoma breakpoint protein, EWS. This EWS interaction was necessary and sufficient for oncogenic ETS functions including gene activation, cell migration, clonogenic survival, and transformation. Significantly, the EWS interacting region of ERG has no homology with that of ETV1, ETV4, and ETV5. Therefore, this finding may explain how divergent ETS factors have a common oncogenic function. Strikingly, EWS is fused to various ETS factors by the chromosome translocations that cause Ewing's sarcoma. Therefore, these findings link oncogenic ETS function in both prostate cancer and Ewing's sarcoma. Copyright © 2016 The Author(s). Published by Elsevier Inc. All rights reserved.

Lipoteichoic Acid (LTA) and Lipopolysaccharides (LPS) from Periodontal Pathogenic Bacteria Facilitate Oncogenic Herpesvirus Infection within Primary Oral Cells

Science.gov (United States)

Dai, Lu; DeFee, Michael R.; Cao, Yueyu; Wen, Jiling; Wen, Xiaofei; Noverr, Mairi C.; Qin, Zhiqiang

2014-01-01

Kaposi’s sarcoma (KS) remains the most common tumor arising in patients with HIV/AIDS, and involvement of the oral cavity represents one of the most common clinical manifestations of this tumor. HIV infection incurs an increased risk for periodontal diseases and oral carriage of a variety of bacteria. Whether interactions involving pathogenic bacteria and oncogenic viruses in the local environment facilitate replication or maintenance of these viruses in the oral cavity remains unknown. In the current study, our data indicate that pretreatment of primary human oral fibroblasts with two prototypical pathogen-associated molecular patterns (PAMPs) produced by oral pathogenic bacteria–lipoteichoic acid (LTA) and lipopolysaccharide (LPS), increase KSHV entry and subsequent viral latent gene expression during de novo infection. Further experiments demonstrate that the underlying mechanisms induced by LTA and/or LPS include upregulation of cellular receptor, increasing production of reactive oxygen species (ROS), and activating intracellular signaling pathways such as MAPK and NF-κB, and all of which are closely associated with KSHV entry or gene expression within oral cells. Based on these findings, we hope to provide the framework of developing novel targeted approaches for treatment and prevention of oral KSHV infection and KS development in high-risk HIV-positive patients. PMID:24971655

Bioinformatics of non small cell lung cancer and the ras proto-oncogene

CERN Document Server

Kashyap, Amita; Babu M, Naresh

2015-01-01

Cancer is initiated by activation of oncogenes or inactivation of tumor suppressor genes. Mutations in the K-ras proto-oncogene are responsible for 10–30% of adenocarcinomas. Clinical Findings point to a wide variety of other cancers contributing to lung cancer incidence. Such a scenario makes identification of lung cancer difficult and thus identifying its mechanisms can contribute to the society. Identifying unique conserved patterns common to contributing proto-oncogenes may further be a boon to Pharmacogenomics and pharmacoinformatics. This calls for ab initio/de novo drug discovery that in turn will require a comprehensive in silico approach of Sequence, Domain, Phylogenetic and Structural analysis of the receptors, ligand screening and optimization and detailed Docking studies. This brief involves extensive role of the RAS subfamily that includes a set of proteins, which cause an over expression of cancer-causing genes like M-ras and initiate tumour formation in lungs. SNP Studies and Structure based ...

Evidences Suggesting Involvement of Viruses in Oral Squamous Cell Carcinoma

Science.gov (United States)

Gupta, Kanupriya; Metgud, Rashmi

2013-01-01

Oral cancer is one of the most common cancers and it constitutes a major health problem particularly in developing countries. Oral squamous cell carcinoma (OSCC) represents the most frequent of all oral neoplasms. Several risk factors have been well characterized to be associated with OSCC with substantial evidences. The etiology of OSCC is complex and involves many factors. The most clearly defined potential factors are smoking and alcohol, which substantially increase the risk of OSCC. However, despite this clear association, a substantial proportion of patients develop OSCC without exposure to them, emphasizing the role of other risk factors such as genetic susceptibility and oncogenic viruses. Some viruses are strongly associated with OSCC while the association of others is less frequent and may depend on cofactors for their carcinogenic effects. Therefore, the exact role of viruses must be evaluated with care in order to improve the diagnosis and treatment of OSCC. Although a viral association within a subset of OSCC has been shown, the molecular and histopathological characteristics of these tumors have yet to be clearly defined. PMID:24455418

Evidences Suggesting Involvement of Viruses in Oral Squamous Cell Carcinoma

Directory of Open Access Journals (Sweden)

Kanupriya Gupta

2013-01-01

Full Text Available Oral cancer is one of the most common cancers and it constitutes a major health problem particularly in developing countries. Oral squamous cell carcinoma (OSCC represents the most frequent of all oral neoplasms. Several risk factors have been well characterized to be associated with OSCC with substantial evidences. The etiology of OSCC is complex and involves many factors. The most clearly defined potential factors are smoking and alcohol, which substantially increase the risk of OSCC. However, despite this clear association, a substantial proportion of patients develop OSCC without exposure to them, emphasizing the role of other risk factors such as genetic susceptibility and oncogenic viruses. Some viruses are strongly associated with OSCC while the association of others is less frequent and may depend on cofactors for their carcinogenic effects. Therefore, the exact role of viruses must be evaluated with care in order to improve the diagnosis and treatment of OSCC. Although a viral association within a subset of OSCC has been shown, the molecular and histopathological characteristics of these tumors have yet to be clearly defined.

Immunodetection of rasP21 and c-myc oncogenes in oral mucosal swab preparation from clove cigarette smokers

Directory of Open Access Journals (Sweden)

Silvi Kintawati

2008-12-01

Full Text Available Background: Smoking is the biggest factor for oral cavity malignancy. Some carcinogens found in cigar will stimulate epithel cell in oral cavity and cause mechanism disturbance on tissue resistance and produce abnormal genes (oncogenes. Oncogenes ras and myc are found on malignant tumor in oral cavity which are associated with smoking. Purpose: This research is to find the expression of oncogenes rasP21 and c-myc in oral mucosa epithelial of smoker with immunocytochemistry reaction. Methods: An oral mucosal swab was performed to 30 smokers categorized as light, moderate, and chain, and 10 non smokers which was followed by immunocytochemistry reaction using antibody towards oncogene rasP21 and c-myc is reacted to identify the influence of smoking towards malignant tumor in oral cavity. The result is statistically analyzed using Kruskal-Wallis test. Result: Based on the observation result of oncogene rasP21reaction, it shows that there is significant difference between non smoker group and light smoker, compared to moderate and chain smoker group (p < 0.01. On the other side, the observation result of oncogene c-myc indicates that there is no significant difference between the group of non smokers and the group of light, moderate, and chain smokers (p > 0.05. Conclusion: The higher the possibility of oral cavity malignancy and that the antibody for rasP21 oncogene can be used as a marker for early detection of oral cavity malignancy caused by smoking.

Oncogenic and incidental HPV types associated with histologically ...

African Journals Online (AJOL)

Background. In Africa, data on the relationship between oncogenic human papillomavirus (HPV) types, immune status and cervical preinvasive lesions are lacking. Methods. We investigated low-risk (lrHPV) and high-risk (hrHPV) HPV types in a cohort of women with cervical intraepithelial neoplasia (CIN) II/III confirmed on ...

Mechanisms of virus immune evasion lead to development from chronic inflammation to cancer formation associated with human papillomavirus infection.

Science.gov (United States)

Senba, Masachika; Mori, Naoki

2012-10-02

Human papillomavirus (HPV) has developed strategies to escape eradication by innate and adaptive immunity. Immune response evasion has been considered an important aspect of HPV persistence, which is the main contributing factor leading to HPV-related cancers. HPV-induced cancers expressing viral oncogenes E6 and E7 are potentially recognized by the immune system. The major histocompatibility complex (MHC) class I molecules are patrolled by natural killer cells and CD8+ cytotoxic T lymphocytes, respectively. This system of recognition is a main target for the strategies of immune evasion deployed by viruses. The viral immune evasion proteins constitute useful tools to block defined stages of the MHC class I presentation pathway, and in this way HPV avoids the host immune response. The long latency period from initial infection to persistence signifies that HPV evolves mechanisms to escape the immune response. It has now been established that there are oncogenic mechanisms by which E7 binds to and degrades tumor suppressor Rb, while E6 binds to and inactivates tumor suppressor p53. Therefore, interaction of p53 and pRb proteins can give rise to an increased immortalization and genomic instability. Overexpression of NF-κB in cervical and penile cancers suggests that NF-κB activation is a key modulator in driving chronic inflammation to cancer. HPV oncogene-mediated suppression of NF-κB activity contributes to HPV escape from the immune system. This review focuses on the diverse mechanisms of the virus immune evasion with HPV that leads to chronic inflammation and cancer.

Understanding personal risk of oropharyngeal cancer: risk-groups for oncogenic oral HPV infection and oropharyngeal cancer.

Science.gov (United States)

D'Souza, G; McNeel, T S; Fakhry, C

2017-12-01

Incidence of human papillomavirus (HPV)-related oropharyngeal cancer is increasing. There is interest in identifying healthy individuals most at risk for development of oropharyngeal cancer to inform screening strategies. All data are from 2009 to 2014, including 13 089 people ages 20-69 in the National Health and Nutrition Examination Survey (NHANES), oropharyngeal cancer cases from the Surveillance, Epidemiology, and End Results (SEER 18) registries (representing ∼28% of the US population), and oropharyngeal cancer mortality from National Center for Health Statistics (NCHS). Primary study outcomes are (i) prevalence of oncogenic HPV DNA in an oral rinse and gargle sample, and (ii) incident oropharyngeal squamous cell cancer. Oncogenic oral HPV DNA is detected in 3.5% of all adults age 20-69 years; however, the lifetime risk of oropharyngeal cancer is low (37 per 10 000). Among men 50-59 years old, 8.1% have an oncogenic oral HPV infection, 2.1% have an oral HPV16 infection, yet only 0.7% will 'ever' develop oropharyngeal cancer in their lifetime. Oncogenic oral HPV prevalence was higher in men than women, and increased with number of lifetime oral sexual partners and tobacco use. Men who currently smoked and had ≥5 lifetime oral sexual partners had 'elevated risk' (prevalence = 14.9%). Men with only one of these risk factors (i.e. either smoked and had 2-4 partners or did not smoke and had ≥5 partners) had 'medium risk' (7.3%). Regardless of what other risk factors participants had, oncogenic oral HPV prevalence was 'low' among those with only ≤1 lifetime oral sexual partner (women = 0.7% and men = 1.7%). Screening based upon oncogenic oral HPV detection would be challenging. Most groups have low oncogenic oral HPV prevalence. In addition to the large numbers of individuals who would need to be screened to identify prevalent oncogenic oral HPV, the lifetime risk of developing oropharyngeal caner among those with infection remains

[Oncogenic action of ionizing radiation

International Nuclear Information System (INIS)

1990-01-01

An extensive experiment involving approximately 400 rats exposed to the neon ion beam at the Bevalac in Berkeley, CA and to electrons is nearing completion. The carcinogenicity of energetic electrons was determined for comparison with the neon ion results. As in past reports we will describe progress in three areas corresponding to the specific aims of the proposal: (1) carcinogenesis and DNA strand breaks in rat skin following exposure by the neon ions or electrons; (2) DNA strand breaks in the epidermis as a function of radiation penetration; (3) oncogene activation in radiation-induced rat skin cancers. 72 refs., 6 tabs

Machine Learning Identifies Stemness Features Associated with Oncogenic Dedifferentiation

NARCIS (Netherlands)

Malta, Tathiane M.; Sokolov, Artem; Gentles, Andrew J.; Burzykowski, Tomasz; Poisson, Laila; Weinstein, John N.; Kamińska, Bożena; Huelsken, Joerg; Omberg, Larsson; Gevaert, Olivier; Colaprico, Antonio; Czerwińska, Patrycja; Mazurek, Sylwia; Mishra, Lopa; Heyn, Holger; Krasnitz, Alex; Godwin, Andrew K.; Lazar, Alexander J.; Caesar-Johnson, Samantha J.; Demchok, John A.; Felau, Ina; Kasapi, Melpomeni; Ferguson, Martin L.; Hutter, Carolyn M.; Sofia, Heidi J.; Tarnuzzer, Roy; Wang, Zhining; Yang, Liming; Zenklusen, Jean C.; Zhang, Jiashan (Julia); Chudamani, Sudha; Liu, Jia; Lolla, Laxmi; Naresh, Rashi; Pihl, Todd; Sun, Qiang; Wan, Yunhu; Wu, Ye; Cho, Juok; DeFreitas, Timothy; Frazer, Scott; Gehlenborg, Nils; Getz, Gad; Heiman, David I.; Kim, Jaegil; Lawrence, Michael S.; Lin, Pei; Meier, Sam; Noble, Michael S.; Saksena, Gordon; Voet, Doug; Zhang, Hailei; Bernard, Brady; Chambwe, Nyasha; Dhankani, Varsha; Knijnenburg, Theo; Kramer, Roger; Leinonen, Kalle; Liu, Yuexin; Miller, Michael; Reynolds, Sheila; Shmulevich, Ilya; Thorsson, Vesteinn; Zhang, Wei; Akbani, Rehan; Broom, Bradley M.; Hegde, Apurva M.; Ju, Zhenlin; Kanchi, Rupa S.; Korkut, Anil; Li, Jun; Liang, Han; Ling, Shiyun; Liu, Wenbin; Lu, Yiling; Mills, Gordon B.; Ng, Kwok Shing; Rao, Arvind; Ryan, Michael; Wang, Jing; Weinstein, John N.; Zhang, Jiexin; Abeshouse, Adam; Armenia, Joshua; Chakravarty, Debyani; Chatila, Walid K.; de Bruijn, Ino; Gao, Jianjiong; Gross, Benjamin E.; Heins, Zachary J.; Kundra, Ritika; La, Konnor; Ladanyi, Marc; Luna, Augustin; Nissan, Moriah G.; Ochoa, Angelica; Phillips, Sarah M.; Reznik, Ed; Sanchez-Vega, Francisco; Sander, Chris; Schultz, Nikolaus; Sheridan, Robert; Sumer, S. Onur; Sun, Yichao; Taylor, Barry S.; Wang, Jioajiao; Zhang, Hongxin; Anur, Pavana; Peto, Myron; Spellman, Paul; Benz, Christopher; Stuart, Joshua M.; Wong, Christopher K.; Yau, Christina; Hayes, D. Neil; Parker, Joel S.; Wilkerson, Matthew D.; Ally, Adrian; Balasundaram, Miruna; Bowlby, Reanne; Brooks, Denise; Carlsen, Rebecca; Chuah, Eric; Dhalla, Noreen; Holt, Robert; Jones, Steven J.M.; Kasaian, Katayoon; Lee, Darlene; Ma, Yussanne; Marra, Marco A.; Mayo, Michael; Moore, Richard A.; Mungall, Andrew J.; Mungall, Karen; Robertson, A. Gordon; Sadeghi, Sara; Schein, Jacqueline E.; Sipahimalani, Payal; Tam, Angela; Thiessen, Nina; Tse, Kane; Wong, Tina; Berger, Ashton C.; Beroukhim, Rameen; Cherniack, Andrew D.; Cibulskis, Carrie; Gabriel, Stacey B.; Gao, Galen F.; Ha, Gavin; Meyerson, Matthew; Schumacher, Steven E.; Shih, Juliann; Kucherlapati, Melanie H.; Kucherlapati, Raju S.; Baylin, Stephen; Cope, Leslie; Danilova, Ludmila; Bootwalla, Moiz S.; Lai, Phillip H.; Maglinte, Dennis T.; Van Den Berg, David J.; Weisenberger, Daniel J.; Auman, J. Todd; Balu, Saianand; Bodenheimer, Tom; Fan, Cheng; Hoadley, Katherine A.; Hoyle, Alan P.; Jefferys, Stuart R.; Jones, Corbin D.; Meng, Shaowu; Mieczkowski, Piotr A.; Mose, Lisle E.; Perou, Amy H.; Perou, Charles M.; Roach, Jeffrey; Shi, Yan; Simons, Janae V.; Skelly, Tara; Soloway, Matthew G.; Tan, Donghui; Veluvolu, Umadevi; Fan, Huihui; Hinoue, Toshinori; Laird, Peter W.; Shen, Hui; Zhou, Wanding; Bellair, Michelle; Chang, Kyle; Covington, Kyle; Creighton, Chad J.; Dinh, Huyen; Doddapaneni, Harsha Vardhan; Donehower, Lawrence A.; Drummond, Jennifer; Gibbs, Richard A.; Glenn, Robert; Hale, Walker; Han, Yi; Hu, Jianhong; Korchina, Viktoriya; Lee, Sandra; Lewis, Lora; Li, Wei; Liu, Xiuping; Morgan, Margaret; Morton, Donna; Muzny, Donna; Santibanez, Jireh; Sheth, Margi; Shinbrot, Eve; Wang, Linghua; Wang, Min; Wheeler, David A.; Xi, Liu; Zhao, Fengmei; Hess, Julian; Appelbaum, Elizabeth L.; Bailey, Matthew; Cordes, Matthew G.; Ding, Li; Fronick, Catrina C.; Fulton, Lucinda A.; Fulton, Robert S.; Kandoth, Cyriac; Mardis, Elaine R.; McLellan, Michael D.; Miller, Christopher A.; Schmidt, Heather K.; Wilson, Richard K.; Crain, Daniel; Curley, Erin; Gardner, Johanna; Lau, Kevin; Mallery, David; Morris, Scott; Paulauskis, Joseph; Penny, Robert; Shelton, Candace; Shelton, Troy; Sherman, Mark; Thompson, Eric; Yena, Peggy; Bowen, Jay; Gastier-Foster, Julie M.; Gerken, Mark; Leraas, Kristen M.; Lichtenberg, Tara M.; Ramirez, Nilsa C.; Wise, Lisa; Zmuda, Erik; Corcoran, Niall; Costello, Tony; Hovens, Christopher; Carvalho, Andre L.; de Carvalho, Ana C.; Fregnani, José H.; Longatto-Filho, Adhemar; Reis, Rui M.; Scapulatempo-Neto, Cristovam; Silveira, Henrique C.S.; Vidal, Daniel O.; Burnette, Andrew; Eschbacher, Jennifer; Hermes, Beth; Noss, Ardene; Singh, Rosy; Anderson, Matthew L.; Castro, Patricia D.; Ittmann, Michael; Huntsman, David; Kohl, Bernard; Le, Xuan; Thorp, Richard; Andry, Chris; Duffy, Elizabeth R.; Lyadov, Vladimir; Paklina, Oxana; Setdikova, Galiya; Shabunin, Alexey; Tavobilov, Mikhail; McPherson, Christopher; Warnick, Ronald; Berkowitz, Ross; Cramer, Daniel; Feltmate, Colleen; Horowitz, Neil; Kibel, Adam; Muto, Michael; Raut, Chandrajit P.; Malykh, Andrei; Barnholtz-Sloan, Jill S.; Barrett, Wendi; Devine, Karen; Fulop, Jordonna; Ostrom, Quinn T.; Shimmel, Kristen; Wolinsky, Yingli; Sloan, Andrew E.; De Rose, Agostino; Giuliante, Felice; Goodman, Marc; Karlan, Beth Y.; Hagedorn, Curt H.; Eckman, John; Harr, Jodi; Myers, Jerome; Tucker, Kelinda; Zach, Leigh Anne; Deyarmin, Brenda; Hu, Hai; Kvecher, Leonid; Larson, Caroline; Mural, Richard J.; Somiari, Stella; Vicha, Ales; Zelinka, Tomas; Bennett, Joseph; Iacocca, Mary; Rabeno, Brenda; Swanson, Patricia; Latour, Mathieu; Lacombe, Louis; Têtu, Bernard; Bergeron, Alain; McGraw, Mary; Staugaitis, Susan M.; Chabot, John; Hibshoosh, Hanina; Sepulveda, Antonia; Su, Tao; Wang, Timothy; Potapova, Olga; Voronina, Olga; Desjardins, Laurence; Mariani, Odette; Roman-Roman, Sergio; Sastre, Xavier; Stern, Marc Henri; Cheng, Feixiong; Signoretti, Sabina; Berchuck, Andrew; Bigner, Darell; Lipp, Eric; Marks, Jeffrey; McCall, Shannon; McLendon, Roger; Secord, Angeles; Sharp, Alexis; Behera, Madhusmita; Brat, Daniel J.; Chen, Amy; Delman, Keith; Force, Seth; Khuri, Fadlo; Magliocca, Kelly; Maithel, Shishir; Olson, Jeffrey J.; Owonikoko, Taofeek; Pickens, Alan; Ramalingam, Suresh; Shin, Dong M.; Sica, Gabriel; Van Meir, Erwin G.; Zhang, Hongzheng; Eijckenboom, Wil; Gillis, Ad; Korpershoek, Esther; Looijenga, Leendert; Oosterhuis, Wolter; Stoop, Hans; van Kessel, Kim E.; Zwarthoff, Ellen C.; Calatozzolo, Chiara; Cuppini, Lucia; Cuzzubbo, Stefania; DiMeco, Francesco; Finocchiaro, Gaetano; Mattei, Luca; Perin, Alessandro; Pollo, Bianca; Chen, Chu; Houck, John; Lohavanichbutr, Pawadee; Hartmann, Arndt; Stoehr, Christine; Stoehr, Robert; Taubert, Helge; Wach, Sven; Wullich, Bernd; Kycler, Witold; Murawa, Dawid; Wiznerowicz, Maciej; Chung, Ki; Edenfield, W. Jeffrey; Martin, Julie; Baudin, Eric; Bubley, Glenn; Bueno, Raphael; De Rienzo, Assunta; Richards, William G.; Kalkanis, Steven; Mikkelsen, Tom; Noushmehr, Houtan; Scarpace, Lisa; Girard, Nicolas; Aymerich, Marta; Campo, Elias; Giné, Eva; Guillermo, Armando López; Van Bang, Nguyen; Hanh, Phan Thi; Phu, Bui Duc; Tang, Yufang; Colman, Howard; Evason, Kimberley; Dottino, Peter R.; Martignetti, John A.; Gabra, Hani; Juhl, Hartmut; Akeredolu, Teniola; Stepa, Serghei; Hoon, Dave; Ahn, Keunsoo; Kang, Koo Jeong; Beuschlein, Felix; Breggia, Anne; Birrer, Michael; Bell, Debra; Borad, Mitesh; Bryce, Alan H.; Castle, Erik; Chandan, Vishal; Cheville, John; Copland, John A.; Farnell, Michael; Flotte, Thomas; Giama, Nasra; Ho, Thai; Kendrick, Michael; Kocher, Jean Pierre; Kopp, Karla; Moser, Catherine; Nagorney, David; O'Brien, Daniel; O'Neill, Brian Patrick; Patel, Tushar; Petersen, Gloria; Que, Florencia; Rivera, Michael; Roberts, Lewis; Smallridge, Robert; Smyrk, Thomas; Stanton, Melissa; Thompson, R. Houston; Torbenson, Michael; Yang, Ju Dong; Zhang, Lizhi; Brimo, Fadi; Ajani, Jaffer A.; Gonzalez, Ana Maria Angulo; Behrens, Carmen; Bondaruk, Jolanta; Broaddus, Russell; Czerniak, Bogdan; Esmaeli, Bita; Fujimoto, Junya; Gershenwald, Jeffrey; Guo, Charles; Lazar, Alexander J.; Logothetis, Christopher; Meric-Bernstam, Funda; Moran, Cesar; Ramondetta, Lois; Rice, David; Sood, Anil; Tamboli, Pheroze; Thompson, Timothy; Troncoso, Patricia; Tsao, Anne; Wistuba, Ignacio; Carter, Candace; Haydu, Lauren; Hersey, Peter; Jakrot, Valerie; Kakavand, Hojabr; Kefford, Richard; Lee, Kenneth; Long, Georgina; Mann, Graham; Quinn, Michael; Saw, Robyn; Scolyer, Richard; Shannon, Kerwin; Spillane, Andrew; Stretch, Jonathan; Synott, Maria; Thompson, John; Wilmott, James; Al-Ahmadie, Hikmat; Chan, Timothy A.; Ghossein, Ronald; Gopalan, Anuradha; Levine, Douglas A.; Reuter, Victor; Singer, Samuel; Singh, Bhuvanesh; Tien, Nguyen Viet; Broudy, Thomas; Mirsaidi, Cyrus; Nair, Praveen; Drwiega, Paul; Miller, Judy; Smith, Jennifer; Zaren, Howard; Park, Joong Won; Hung, Nguyen Phi; Kebebew, Electron; Linehan, W. Marston; Metwalli, Adam R.; Pacak, Karel; Pinto, Peter A.; Schiffman, Mark; Schmidt, Laura S.; Vocke, Cathy D.; Wentzensen, Nicolas; Worrell, Robert; Yang, Hannah; Moncrieff, Marc; Goparaju, Chandra; Melamed, Jonathan; Pass, Harvey; Botnariuc, Natalia; Caraman, Irina; Cernat, Mircea; Chemencedji, Inga; Clipca, Adrian; Doruc, Serghei; Gorincioi, Ghenadie; Mura, Sergiu; Pirtac, Maria; Stancul, Irina; Tcaciuc, Diana; Albert, Monique; Alexopoulou, Iakovina; Arnaout, Angel; Bartlett, John; Engel, Jay; Gilbert, Sebastien; Parfitt, Jeremy; Sekhon, Harman; Thomas, George; Rassl, Doris M.; Rintoul, Robert C.; Bifulco, Carlo; Tamakawa, Raina; Urba, Walter; Hayward, Nicholas; Timmers, Henri; Antenucci, Anna; Facciolo, Francesco; Grazi, Gianluca; Marino, Mirella; Merola, Roberta; de Krijger, Ronald; Gimenez-Roqueplo, Anne Paule; Piché, Alain; Chevalier, Simone; McKercher, Ginette; Birsoy, Kivanc; Barnett, Gene; Brewer, Cathy; Farver, Carol; Naska, Theresa; Pennell, Nathan A.; Raymond, Daniel; Schilero, Cathy; Smolenski, Kathy; Williams, Felicia; Morrison, Carl; Borgia, Jeffrey A.; Liptay, Michael J.; Pool, Mark; Seder, Christopher W.; Junker, Kerstin; Omberg, Larsson; Dinkin, Mikhail; Manikhas, George; Alvaro, Domenico; Bragazzi, Maria Consiglia; Cardinale, Vincenzo; Carpino, Guido; Gaudio, Eugenio; Chesla, David; Cottingham, Sandra; Dubina, Michael; Moiseenko, Fedor; Dhanasekaran, Renumathy; Becker, Karl Friedrich; Janssen, Klaus Peter; Slotta-Huspenina, Julia; Abdel-Rahman, Mohamed H.; Aziz, Dina; Bell, Sue; Cebulla, Colleen M.; Davis, Amy; Duell, Rebecca; Elder, J. Bradley; Hilty, Joe; Kumar, Bahavna; Lang, James; Lehman, Norman L.; Mandt, Randy; Nguyen, Phuong; Pilarski, Robert; Rai, Karan; Schoenfield, Lynn; Senecal, Kelly; Wakely, Paul; Hansen, Paul; Lechan, Ronald; Powers, James; Tischler, Arthur; Grizzle, William E.; Sexton, Katherine C.; Kastl, Alison; Henderson, Joel; Porten, Sima; Waldmann, Jens; Fassnacht, Martin; Asa, Sylvia L.; Schadendorf, Dirk; Couce, Marta; Graefen, Markus; Huland, Hartwig; Sauter, Guido; Schlomm, Thorsten; Simon, Ronald; Tennstedt, Pierre; Olabode, Oluwole; Nelson, Mark; Bathe, Oliver; Carroll, Peter R.; Chan, June M.; Disaia, Philip; Glenn, Pat; Kelley, Robin K.; Landen, Charles N.; Phillips, Joanna; Prados, Michael; Simko, Jeffry; Smith-McCune, Karen; VandenBerg, Scott; Roggin, Kevin; Fehrenbach, Ashley; Kendler, Ady; Sifri, Suzanne; Steele, Ruth; Jimeno, Antonio; Carey, Francis; Forgie, Ian; Mannelli, Massimo; Carney, Michael; Hernandez, Brenda; Campos, Benito; Herold-Mende, Christel; Jungk, Christin; Unterberg, Andreas; von Deimling, Andreas; Bossler, Aaron; Galbraith, Joseph; Jacobus, Laura; Knudson, Michael; Knutson, Tina; Ma, Deqin; Milhem, Mohammed; Sigmund, Rita; Godwin, Andrew K.; Madan, Rashna; Rosenthal, Howard G.; Adebamowo, Clement; Adebamowo, Sally N.; Boussioutas, Alex; Beer, David; Giordano, Thomas; Mes-Masson, Anne Marie; Saad, Fred; Bocklage, Therese; Landrum, Lisa; Mannel, Robert; Moore, Kathleen; Moxley, Katherine; Postier, Russel; Walker, Joan; Zuna, Rosemary; Feldman, Michael; Valdivieso, Federico; Dhir, Rajiv; Luketich, James; Pinero, Edna M.Mora; Quintero-Aguilo, Mario; Carlotti, Carlos Gilberto; Dos Santos, Jose Sebastião; Kemp, Rafael; Sankarankuty, Ajith; Tirapelli, Daniela; Catto, James; Agnew, Kathy; Swisher, Elizabeth; Creaney, Jenette; Robinson, Bruce; Shelley, Carl Simon; Godwin, Eryn M.; Kendall, Sara; Shipman, Cassaundra; Bradford, Carol; Carey, Thomas; Haddad, Andrea; Moyer, Jeffey; Peterson, Lisa; Prince, Mark; Rozek, Laura; Wolf, Gregory; Bowman, Rayleen; Fong, Kwun M.; Yang, Ian; Korst, Robert; Rathmell, W. Kimryn; Fantacone-Campbell, J. Leigh; Hooke, Jeffrey A.; Kovatich, Albert J.; Shriver, Craig D.; DiPersio, John; Drake, Bettina; Govindan, Ramaswamy; Heath, Sharon; Ley, Timothy; Van Tine, Brian; Westervelt, Peter; Rubin, Mark A.; Lee, Jung Il; Aredes, Natália D.; Mariamidze, Armaz; Stuart, Joshua M.; Hoadley, Katherine A.; Laird, Peter W.; Noushmehr, Houtan; Wiznerowicz, Maciej

2018-01-01

Cancer progression involves the gradual loss of a differentiated phenotype and acquisition of progenitor and stem-cell-like features. Here, we provide novel stemness indices for assessing the degree of oncogenic dedifferentiation. We used an innovative one-class logistic regression (OCLR)

The H3K27me3 demethylase, KDM6B, is induced by Epstein-Barr virus and over-expressed in Hodgkin's Lymphoma

DEFF Research Database (Denmark)

Anderton, J A; Bose, S; Vockerodt, M

2011-01-01

), an Epstein-Barr virus (EBV) associated malignancy. KDM6B is over-expressed in primary HL and induced by the EBV oncogene, latent membrane protein (LMP1) in GC B cells, the presumptive progenitors of HL. Consistent with these observations, we found that KDM6B transcriptional targets in GC B cells are enriched...

Characterization of a human cell line stably over-expressing the candidate oncogene, dual specificity phosphatase 12.

Directory of Open Access Journals (Sweden)

Erica L Cain

2011-04-01

Full Text Available Analysis of chromosomal rearrangements within primary tumors has been influential in the identification of novel oncogenes. Identification of the "driver" gene(s within cancer-derived amplicons is, however, hampered by the fact that most amplicons contain many gene products. Amplification of 1q21-1q23 is strongly associated with liposarcomas and microarray-based comparative genomic hybridization narrowed down the likely candidate oncogenes to two: the activating transcription factor 6 (atf6 and the dual specificity phosphatase 12 (dusp12. While atf6 is an established transcriptional regulator of the unfolded protein response, the potential role of dusp12 in cancer remains uncharacterized.To evaluate the oncogenic potential of dusp12, we established stable cell lines that ectopically over-express dusp12 in isolation and determined whether this cell line acquired properties frequently associated with transformed cells. Here, we demonstrate that cells over-expressing dusp12 display increased cell motility and resistance to apoptosis. Additionally, over-expression of dusp12 promoted increased expression of the c-met proto-oncogene and the collagen and laminin receptor intergrin alpha 1 (itga1 which is implicated in metastasis.Collectively, these results suggest that dusp12 is oncologically relevant and exposes a potential association between dusp12 and established oncogenes that could be therapeutically targeted.

Suppressor of cytokine signaling 1 interacts with oncogenic lymphocyte-specific protein tyrosine kinase.

Science.gov (United States)

Venkitachalam, Srividya; Chueh, Fu-Yu; Leong, King-Fu; Pabich, Samantha; Yu, Chao-Lan

2011-03-01

Lymphocyte-specific protein tyrosine kinase (Lck) plays a key role in T cell signal transduction and is tightly regulated by phosphorylation and dephosphorylation. Lck can function as an oncoprotein when overexpressed or constantly activated by mutations. Our previous studies showed that Lck-induced cellular transformation could be suppressed by enforced expression of suppressor of cytokine signaling 1 (SOCS1), a SOCS family member involved in the negative feedback control of cytokine signaling. We observed attenuated Lck kinase activity in SOCS1-expressing cells, suggesting an important role of SOCS in regulating Lck functions. It remains largely unknown whether and how SOCS proteins interact with the oncogenic Lck kinase. Here, we report that among four SOCS family proteins, SOCS1, SOCS2, SOCS3 and CIS (cytokine-inducible SH2 domain containing protein), SOCS1 has the highest affinity in binding to the oncogenic Lck kinase. We identified the positive regulatory phosphotyrosine 394 residue in the kinase domain as the key interacting determinant in Lck. Additionally, the Lck kinase domain alone is sufficient to bind SOCS1. While the SH2 domain in SOCS1 is important in its association with the oncogenic Lck kinase, other functional domains may also contribute to overall binding affinity. These findings provide important mechanistic insights into the role of SOCS proteins as tumor suppressors in cells transformed by oncogenic protein tyrosine kinases.

Proto-oncogene expression: a predictive assay for radiation biodosimetry applications

Energy Technology Data Exchange (ETDEWEB)

Miller, A.C.; Luo, L.; Chin, W.K.; Director-Myska, A.E.; Prasanna, P.G.S.; Blakely, W.F

2002-07-01

Using a model system of in vitro human peripheral blood lymphocytes, the effect of low-dose (0.25 to 1.50 Gy) 250-kV{sub p} X ray radiation (1 Gy.min{sup -1}) on the expression of several proto-oncogenes was examined (c-Haras, c-src, c-met, c-jun, c-fos, and c-myc) and {beta}-actin from 0.25 to 17 h post-radiation. RNA was extracted from cells harvested at various times after exposure and examined for levels of particular mRNAs by northern blot hybridisation. A progressive time- and dose-dependent increase in mRNA levels was observed for c-Haras mRNA, while the other proto-oncogenes (c-src, c-met, c-fos, c-jun, and c-myc) examined were variable during the same time period. {beta}-actin levels were initially decreased but at 17 h post-radiation had returned to control levels. A comparison of the rate of c-Haras transcription at 5 and 17 h post-irradiation revealed that c-Haras transcription was higher at 5 h than at 17 h. These findings suggest that the level of specific proto-oncogene expression, particularly c-Haras, may be useful early diagnostic molecular biomarkers for biodosimetry applications. The use of real-time PCR technologies to quantify gene expression changes will also be discussed. (author)

 Oncogenic osteomalacia and its symptoms: hypophosphatemia, bone pain and pathological fractures

Directory of Open Access Journals (Sweden)

Sonia Kaniuka-Jakubowska

2012-08-01

Full Text Available  Oncogenic osteomalacia (OOM is a rare paraneoplastic syndrome induced by tumor produced phosphaturic factors, i.e. phosphatonins. The disorder is characterized by renal tubular phosphate loss, secondary to this process hypophosphatemia and defective production of active form of vitamin D. The clinical course of oncogenic osteomalacia is characterized by bone pain, pathological fractures, muscle weakness and general fatigue. Osteomalacia-associated tumors are usually located in the upper and lower limbs, with half of the lesions primarily situated in the bones. Most of them are small, slow-growing tumors. Their insignificant size and various location coupled with rare occurrence of the disease and non-specificity of clinical symptoms lead to difficulties in reaching a diagnosis, which is often time-consuming and requires a number of additional tests. The average time between the appearance of the first symptoms and the establishment of an accurate diagnosis and the beginning of treatment is over 2.5 years. The aim of this study is to discuss the pathophysiology of disease symptoms, pathomorphology of tumors, diagnostic methods and treatment of oncogenic osteomalacia.

Comparison of the oncogenic potential of several chemotherapeutic agents

International Nuclear Information System (INIS)

Miller, R.C.; Hall, E.J.; Osmak, R.S.

1981-01-01

Several chemotherapeutic drugs that have been routinely used in cancer treatment were tested for their carcinogenic potential. Two antitumor antibiotics (adriamycin and vincristine), an alkalating agent (melphalan), 5-azacytidine and the bifunctional agent cis-platinum that mimics alkylating agents and/or binds Oxygen-6 or Nitrogen-7 atoms of quanine were tested. Cell killing and cancer induction was assessed using in vitro transformation system. C3H/10T 1/2 cells, while normally exhibiting contact inhibition, can undergo transformation from normal contact inhibited cells to tumorgenic cells when exposed to chemical carcinogens. These cells have been used in the past by this laboratory to study oncogenic transformation of cells exposed to ionizing radiation and electron affinic compounds that sensitize hypoxic cells to x-rays. The endpoints of cell killing and oncogenic transformation presented here give an estimate of the carcinogenic potential of these agents

Oncogenic RAS enables DNA damage- and p53-dependent differentiation of acute myeloid leukemia cells in response to chemotherapy.

Directory of Open Access Journals (Sweden)

Mona Meyer

Full Text Available Acute myeloid leukemia (AML is a clonal disease originating from myeloid progenitor cells with a heterogeneous genetic background. High-dose cytarabine is used as the standard consolidation chemotherapy. Oncogenic RAS mutations are frequently observed in AML, and are associated with beneficial response to cytarabine. Why AML-patients with oncogenic RAS benefit most from high-dose cytarabine post-remission therapy is not well understood. Here we used bone marrow cells expressing a conditional MLL-ENL-ER oncogene to investigate the interaction of oncogenic RAS and chemotherapeutic agents. We show that oncogenic RAS synergizes with cytotoxic agents such as cytarabine in activation of DNA damage checkpoints, resulting in a p53-dependent genetic program that reduces clonogenicity and increases myeloid differentiation. Our data can explain the beneficial effects observed for AML patients with oncogenic RAS treated with higher dosages of cytarabine and suggest that induction of p53-dependent differentiation, e.g. by interfering with Mdm2-mediated degradation, may be a rational approach to increase cure rate in response to chemotherapy. The data also support the notion that the therapeutic success of cytotoxic drugs may depend on their ability to promote the differentiation of tumor-initiating cells.

Oncogenic programmes and Notch activity: an 'organized crime'?

Science.gov (United States)

Dominguez, Maria

2014-04-01

The inappropriate Notch signalling can influence virtually all aspect of cancer, including tumour-cell growth, survival, apoptosis, angiogenesis, invasion and metastasis, although it does not do this alone. Hence, elucidating the partners of Notch that are active in cancer is now the focus of much intense research activity. The genetic toolkits available, coupled to the small size and short life of the fruit fly Drosophila melanogaster, makes this an inexpensive and effective animal model, suited to large-scale cancer gene discovery studies. The fly eye is not only a non-vital organ but its stereotyped size and disposition also means it is easy to screen for mutations that cause tumours and metastases and provides ample opportunities to test cancer theories and to unravel unanticipated nexus between Notch and other cancer genes, or to discover unforeseen Notch's partners in cancer. These studies suggest that Notch's oncogenic capacity is brought about not simply by increasing signal strength but through partnerships, whereby oncogenes gain more by cooperating than acting individually, as in a ring 'organized crime'. Copyright © 2014 Elsevier Ltd. All rights reserved.

Limited role of murine ATM in oncogene-induced senescence and p53-dependent tumor suppression.

Directory of Open Access Journals (Sweden)

Alejo Efeyan

Full Text Available Recent studies in human fibroblasts have provided a new general paradigm of tumor suppression according to which oncogenic signaling produces DNA damage and this, in turn, results in ATM/p53-dependent cellular senescence. Here, we have tested this model in a variety of murine experimental systems. Overexpression of oncogenic Ras in murine fibroblasts efficiently induced senescence but this occurred in the absence of detectable DNA damage signaling, thus suggesting a fundamental difference between human and murine cells. Moreover, lung adenomas initiated by endogenous levels of oncogenic K-Ras presented abundant senescent cells, but undetectable DNA damage signaling. Accordingly, K-Ras-driven adenomas were also senescent in Atm-null mice, and the tumorigenic progression of these lesions was only modestly accelerated by Atm-deficiency. Finally, we have examined chemically-induced fibrosarcomas, which possess a persistently activated DNA damage response and are highly sensitive to the activity of p53. We found that the absence of Atm favored genomic instability in the resulting tumors, but did not affect the persistent DNA damage response and did not impair p53-dependent tumor suppression. All together, we conclude that oncogene-induced senescence in mice may occur in the absence of a detectable DNA damage response. Regarding murine Atm, our data suggest that it plays a minor role in oncogene-induced senescence or in p53-dependent tumor suppression, being its tumor suppressive activity probably limited to the maintenance of genomic stability.

[The LMP1 oncogene sequence variations in patients with oral tumours associated or not associated with the Epstein Barr].

Science.gov (United States)

Gurtsevitch, V E; Iakovleva, L S; Shcherbak, L N; Goncharova, E V; Smirnova, K V; Diduk, S V; Kondratova, V N; Maksimovich, D M; Lichtenstein, A V; Seniuta, N B

2013-01-01

The role of the Epstein-Barr virus (EBV), a ubiquitous lymphotropic human herpesvirus type 4, in the etiology of nasopharyngeal carcinoma (NPC) is not fully understood. The mechanism of NPC carcinogenesis, associated with the virus, is also not clear. The objective of present investigation was to carry out comparative analysis of the structure of an LMP1 oncogene of EBV in viral isolates obtained from patients with two types of tumors of the oral cavity: (a) associated (i.e., NPC) and (b) not associated (other tumors of the same anatomical region, OTOC) with EBV. Comparative analysis of C-terminal regions of LMP1 variants that was based on a sequence analysis of LMP1 from tumor, blood and throat washing samples of NPC and OTOC patients showed that all structural characteristics of LMP1 in both groups of patients were genetically similar, and differences found between compared parameters were statistically insignificant. Thus, for the first time it has been revealed that in NPC and OTOC patients in Russia genetically related EBV strains with structurally similar LMP1 variants are persisting that are likely to reflect a polymorphism of the virus circulating in population. The findings allow us to suggest that in non-NPC-endemic regions of the world, which include Russia, the risk of NPC development does not depend on the EBVstrain and its variant of LMP1 so much, but mostly from the genetic predisposition of infected persons to the disease and the exposure to other, as yet unknown agents.

Malignant transformation of diploid human fibroblasts by transfection of oncogenes

Energy Technology Data Exchange (ETDEWEB)

McCormick, J.J.

1992-01-01

This document consist of brief reports prepared by postdoctoral students supported by the project, each describing his accomplishments under the grant. Topics include (1) Malignant Transformation of MSU-1. 1 Cells by Gamma Radiation, (2) Correlation between Levels of ras Expression and Presence of Transformed Phenotypes Including Tumorigenicity, Using a Modulatable Promoter, (3) Relation between Specific rad Oncogene Expression, (4) Correlation of Genetic Changes in Fibroblastic Tumors with Malignancies, (5)Transformation of MSU-1.1 Cells by sis Oncogene, (6) Malignant Transformation of MSU-1.0 Cells, (7) Correlation of Urokinase Plasminogen Activation (mu-PA) with Malignant Phenotype, (8)Two Dimensional Gel Electrophoresis Studies of the Proteins of the Major Cell Strains of the MSU-1 Family of Cells, and (9) Correlation between Proteinase Activity Levels and Malignancy.

Malignant transformation of diploid human fibroblasts by transfection of oncogenes

International Nuclear Information System (INIS)

McCormick, J.J.

1992-01-01

This document consist of brief reports prepared by postdoctoral students supported by the project, each describing his accomplishments under the grant. Topics include (1) Malignant Transformation of MSU-1. 1 Cells by Gamma Radiation, (2) Correlation between Levels of ras Expression and Presence of Transformed Phenotypes Including Tumorigenicity, Using a Modulatable Promoter, (3) Relation between Specific rad Oncogene Expression, (4) Correlation of Genetic Changes in Fibroblastic Tumors with Malignancies, (5)Transformation of MSU-1.1 Cells by sis Oncogene, (6) Malignant Transformation of MSU-1.0 Cells, (7) Correlation of Urokinase Plasminogen Activation (mu-PA) with Malignant Phenotype, (8)Two Dimensional Gel Electrophoresis Studies of the Proteins of the Major Cell Strains of the MSU-1 Family of Cells, and (9) Correlation between Proteinase Activity Levels and Malignancy

Oncogenic K-Ras Activates p38 to Maintain Colorectal Cancer Cell Proliferation during MEK Inhibition

Directory of Open Access Journals (Sweden)

Winan J. van Houdt

2010-01-01

Full Text Available Background: Colon carcinomas frequently contain activating mutations in the K-ras proto-oncogene. K-ras itself is a poor drug target and drug development efforts have mostly focused on components of the classical Ras-activated MEK/ERK pathway. Here we have studied whether endogenous oncogenic K-ras affects the dependency of colorectal tumor cells on MEK/ERK signaling.

Effects of c-myc oncogene modulation on differentiation of human small cell lung carcinoma cell lines

NARCIS (Netherlands)

Van Waardenburg, RCAM; Meijer, C; Pinto-Sietsma, SJ; De Vries, EGE; Timens, W; Mulder, NM

1998-01-01

Amplification and over-expression of oncogenes of the myc family are related to the prognosis of certain solid tumors such as small cell lung cancer (SCLC). For SCLC, c-myc is the oncogene most consistently found to correlate with the end stage behaviour of the tumour, in particular with survival

Oncogenic fusion proteins adopt the insulin-like growth factor signaling pathway.

Science.gov (United States)

Werner, Haim; Meisel-Sharon, Shilhav; Bruchim, Ilan

2018-02-19

The insulin-like growth factor-1 receptor (IGF1R) has been identified as a potent anti-apoptotic, pro-survival tyrosine kinase-containing receptor. Overexpression of the IGF1R gene constitutes a typical feature of most human cancers. Consistent with these biological roles, cells expressing high levels of IGF1R are expected not to die, a quintessential feature of cancer cells. Tumor specific chromosomal translocations that disrupt the architecture of transcription factors are a common theme in carcinogenesis. Increasing evidence gathered over the past fifteen years demonstrate that this type of genomic rearrangements is common not only among pediatric and hematological malignancies, as classically thought, but may also provide a molecular and cytogenetic foundation for an ever-increasing portion of adult epithelial tumors. In this review article we provide evidence that the mechanism of action of oncogenic fusion proteins associated with both pediatric and adult malignancies involves transactivation of the IGF1R gene, with ensuing increases in IGF1R levels and ligand-mediated receptor phosphorylation. Disrupted transcription factors adopt the IGF1R signaling pathway and elicit their oncogenic activities via activation of this critical regulatory network. Combined targeting of oncogenic fusion proteins along with the IGF1R may constitute a promising therapeutic approach.

Knowledge and perception of human papilloma virus vaccine among the antenatal women in a Nigerian tertiary hospital

OpenAIRE

Agida, Teddy E.; Akaba, Godwin O.; Isah, Aliyu Y.; Ekele, Bissalla

2015-01-01

Background: Cervical cancer is a major health problem globally, especially in sub-Saharan Africa, Nigeria inclusive. One of the preventive measures is the vaccination of teenagers against oncogenic human papilloma virus. The aim of this study was to find out the level of knowledge mothers possess about these vaccines and their willingness to administer vaccination to their teenage girls. Materials and Methods: This was a cross-sectional descriptive study of 255 consecutive women attending ant...

Human Natural Killer Cells Prevent Infectious Mononucleosis Features by Targeting Lytic Epstein-Barr Virus Infection

Directory of Open Access Journals (Sweden)

Obinna Chijioke

2013-12-01

Full Text Available Primary infection with the human oncogenic Epstein-Barr virus (EBV can result in infectious mononucleosis (IM, a self-limiting disease caused by massive lymphocyte expansion that predisposes for the development of distinct EBV-associated lymphomas. Why some individuals experience this symptomatic primary EBV infection, whereas the majority acquires the virus asymptomatically, remains unclear. Using a mouse model with reconstituted human immune system components, we show that depletion of human natural killer (NK cells enhances IM symptoms and promotes EBV-associated tumorigenesis mainly because of a loss of immune control over lytic EBV infection. These data suggest that failure of innate immune control by human NK cells augments symptomatic lytic EBV infection, which drives lymphocyte expansion and predisposes for EBV-associated malignancies.

Genital condyloma virus infection following pelvic radiation therapy: report of seven cases

International Nuclear Information System (INIS)

Lowell, D.M.; Livolsi, V.A.; Ludwig, M.E.

1983-01-01

Six women who underwent radiation therapy for gynecologic malignancies demonstrated cytologic evidence of condyloma virus infection 2 or more years following radiation. Histologic confirmation was obtained in two of the cases. A seventh patient developed in situ and invasive squamous cell carcinoma in a vulvar condyloma acuminatum following radiation therapy for Hodgkin's disease. This venereal infection is found most frequently in sexually active younger women (average age, 27 years). It is felt that depressed cell-mediated immunity consequent to the radiation therapy allowed the development of this infection in the older patients described in this report. The evolution of invasive squamous cell carcinoma in the condyloma acuminatum may indicate a possible oncogenic or cocarcinogenic effect of the virus. The immunologic responses to infection caused by the human papillomavirus group are discussed, as well as its potential for malignant transformation

A chimeric 18L1-45RG1 virus-like particle vaccine cross-protects against oncogenic alpha-7 human papillomavirus types.

Directory of Open Access Journals (Sweden)

Bettina Huber

Full Text Available Persistent infection with oncogenic human papillomaviruses (HPV types causes all cervical and a subset of other anogenital and oropharyngeal carcinomas. Four high-risk (hr mucosal types HPV16, 18, 45, or 59 cause almost all cervical adenocarcinomas (AC, a subset of cervical cancer (CxC. Although the incidence of cervical squamous cell carcinoma (SCC has dramatically decreased following introduction of Papanicolaou (PAP screening, the proportion of AC has relatively increased. Cervical SCC arise mainly from the ectocervix, whereas AC originate primarily from the endocervical canal, which is less accessible to obtain viable PAP smears. Licensed (bivalent and quadrivalent HPV vaccines comprise virus-like particles (VLP of the most important hr HPV16 and 18, self-assembled from the major capsid protein L1. Due to mainly type-restricted efficacy, both vaccines do not target 13 additional hr mucosal types causing 30% of CxC. The papillomavirus genus alpha species 7 (α7 includes a group of hr types of which HPV18, 45, 59 are proportionally overrepresented in cervical AC and only partially (HPV18 targeted by current vaccines. To target these types, we generated a chimeric vaccine antigen that consists of a cross-neutralizing epitope (homologue of HPV16 RG1 of the L2 minor capsid protein of HPV45 genetically inserted into a surface loop of HPV18 L1 VLP (18L1-45RG1. Vaccination of NZW rabbits with 18L1-45RG1 VLP plus alum-MPL adjuvant induced high-titer neutralizing antibodies against homologous HPV18, that cross-neutralized non-cognate hr α7 types HPV39, 45, 68, but not HPV59, and low risk HPV70 in vitro, and induced a robust L1-specific cellular immune response. Passive immunization protected mice against experimental vaginal challenge with pseudovirions of HPV18, 39, 45 and 68, but not HPV59 or the distantly related α9 type HPV16. 18L1-45RG1 VLP might be combined with our previously described 16L1-16RG1 VLP to develop a second generation bivalent

The small FOXP1 isoform predominantly expressed in activated B cell-like diffuse large B-cell lymphoma and full-length FOXP1 exert similar oncogenic and transcriptional activity in human B cells.

Science.gov (United States)

van Keimpema, Martine; Grüneberg, Leonie J; Schilder-Tol, Esther J M; Oud, Monique E C M; Beuling, Esther A; Hensbergen, Paul J; de Jong, Johann; Pals, Steven T; Spaargaren, Marcel

2017-03-01

The forkhead transcription factor FOXP1 is generally regarded as an oncogene in activated B cell-like diffuse large B-cell lymphoma. Previous studies have suggested that a small isoform of FOXP1 rather than full-length FOXP1, may possess this oncogenic activity. Corroborating those studies, we herein show that activated B cell-like diffuse large B-cell lymphoma cell lines and primary activated B cell-like diffuse large B-cell lymphoma cells predominantly express a small FOXP1 isoform, and that the 5'-end of the Foxp1 gene is a common insertion site in murine lymphomas in leukemia virus- and transposon-mediated insertional mutagenesis screens. By combined mass spectrometry, (quantative) reverse transcription polymerase chain reaction/sequencing, and small interfering ribonucleic acid-mediated gene silencing, we determined that the small FOXP1 isoform predominantly expressed in activated B cell-like diffuse large B-cell lymphoma lacks the N-terminal 100 amino acids of full-length FOXP1. Aberrant overexpression of this FOXP1 isoform (ΔN100) in primary human B cells revealed its oncogenic capacity; it repressed apoptosis and plasma cell differentiation. However, no difference in potency was found between this small FOXP1 isoform and full-length FOXP1. Furthermore, overexpression of full-length FOXP1 or this small FOXP1 isoform in primary B cells and diffuse large B-cell lymphoma cell lines resulted in similar gene regulation. Taken together, our data indicate that this small FOXP1 isoform and full-length FOXP1 have comparable oncogenic and transcriptional activity in human B cells, suggesting that aberrant expression or overexpression of FOXP1, irrespective of the specific isoform, contributes to lymphomagenesis. These novel insights further enhance the value of FOXP1 for the diagnostics, prognostics, and treatment of diffuse large B-cell lymphoma patients. Copyright© Ferrata Storti Foundation.

Oncogenic osteomalacia presenting as bilateral stress fractures of the tibia

International Nuclear Information System (INIS)

Ohashi, Kenjirou; Ohnishi, Takeshi; Ishikawa, Tohru; Tani, Haruo; Uesugi, Keisuke; Takagi, Masayuki

1999-01-01

We report on a patient with bilateral stress fractures of the tibia who subsequently showed classic biochemical features of oncogenic osteomalacia. Conventional radiographs were normal. MR imaging revealed symmetric, bilateral, band-like low-signal lesions perpendicular to the medial cortex of the tibiae and corresponding to the only lesions subsequently seen on the bone scan. A maxillary sinus lesion was subsequently detected and surgically removed resulting in prompt alleviation of symptoms and normalization of hypophosphatemia and low 1,25-(OH) 2 vitamin D 3 . The lesion was pathologically diagnosed as a hemangiopericytoma-like tumor. Patients with oncogenic osteomalacia may present with stress fractures limited to the tibia, as seen in athletes. The clue to the real diagnosis lies in paying close attention to the serum phosphate levels, especially in patients suffering generalized symptoms of weakness and not given to unusual physical activity. (orig.)

Reverse engineering of TLX oncogenic transcriptional networks identifies RUNX1 as tumor suppressor in T-ALL.

Science.gov (United States)

Della Gatta, Giusy; Palomero, Teresa; Perez-Garcia, Arianne; Ambesi-Impiombato, Alberto; Bansal, Mukesh; Carpenter, Zachary W; De Keersmaecker, Kim; Sole, Xavier; Xu, Luyao; Paietta, Elisabeth; Racevskis, Janis; Wiernik, Peter H; Rowe, Jacob M; Meijerink, Jules P; Califano, Andrea; Ferrando, Adolfo A

2012-02-26

The TLX1 and TLX3 transcription factor oncogenes have a key role in the pathogenesis of T cell acute lymphoblastic leukemia (T-ALL). Here we used reverse engineering of global transcriptional networks to decipher the oncogenic regulatory circuit controlled by TLX1 and TLX3. This systems biology analysis defined T cell leukemia homeobox 1 (TLX1) and TLX3 as master regulators of an oncogenic transcriptional circuit governing T-ALL. Notably, a network structure analysis of this hierarchical network identified RUNX1 as a key mediator of the T-ALL induced by TLX1 and TLX3 and predicted a tumor-suppressor role for RUNX1 in T cell transformation. Consistent with these results, we identified recurrent somatic loss-of-function mutations in RUNX1 in human T-ALL. Overall, these results place TLX1 and TLX3 at the top of an oncogenic transcriptional network controlling leukemia development, show the power of network analyses to identify key elements in the regulatory circuits governing human cancer and identify RUNX1 as a tumor-suppressor gene in T-ALL.

Radiation-induced Epstein-Barr virus reactivation in gastric cancer cells with latent EBV infection.

Science.gov (United States)

Nandakumar, Athira; Uwatoko, Futoshi; Yamamoto, Megumi; Tomita, Kazuo; Majima, Hideyuki J; Akiba, Suminori; Koriyama, Chihaya

2017-07-01

Epstein-Barr virus, a ubiquitous human herpes virus with oncogenic activity, can be found in 6%-16% of gastric carcinomas worldwide. In Epstein-Barr virus-associated gastric carcinoma, only a few latent genes of the virus are expressed. Ionizing irradiation was shown to induce lytic Epstein-Barr virus infection in lymphoblastoid cell lines with latent Epstein-Barr virus infection. In this study, we examined the effect of ionizing radiation on the Epstein-Barr virus reactivation in a gastric epithelial cancer cell line (SNU-719, an Epstein-Barr virus-associated gastric carcinoma cell line). Irradiation with X-ray (dose = 5 and 10 Gy; dose rate = 0.5398 Gy/min) killed approximately 25% and 50% of cultured SNU-719 cells, respectively, in 48 h. Ionizing radiation increased the messenger RNA expression of immediate early Epstein-Barr virus lytic genes (BZLF1 and BRLF1), determined by real-time reverse transcription polymerase chain reaction, in a dose-dependent manner at 48 h and, to a slightly lesser extent, at 72 h after irradiation. Similar findings were observed for other Epstein-Barr virus lytic genes (BMRF1, BLLF1, and BcLF1). After radiation, the expression of transforming growth factor beta 1 messenger RNA increased and reached a peak in 12-24 h, and the high-level expression of the Epstein-Barr virus immediate early genes can convert latent Epstein-Barr virus infection into the lytic form and result in the release of infectious Epstein-Barr virus. To conclude, Ionizing radiation activates lytic Epstein-Barr virus gene expression in the SNU-719 cell line mainly through nuclear factor kappaB activation. We made a brief review of literature to explore underlying mechanism involved in transforming growth factor beta-induced Epstein-Barr virus reactivation. A possible involvement of nuclear factor kappaB was hypothesized.

Epstein-Barr Virus-associated lymphoproliferative disorders: experimental and clinical developments

Science.gov (United States)

Geng, Lingyun; Wang, Xin

2015-01-01

Epstein-Barr Virus (EBV), the first human virus related to oncogenesis, was initially identified in a Burkitt lymphoma cell line in 1964. EBV infects over 90% of the world’s population. Most infected people maintain an asymptomatic but persistent EBV infection lifelong. However, in some individuals, EBV infection has been involved in the development of cancer and autoimmune disease. Nowadays, oncogenic potential of EBV has been intensively studied in a wide range of human neoplasms, including Hodgkin’s lymphoma (HL), non-Hodgkin’s lymphoma (NHL), nasopharyngeal carcinoma (NPC), gastric carcinoma (GC), etc. EBV encodes a series of viral protein and miRNAs, promoting its persistent infection and the transformation of EBV-infected cells. Although the exact role of EBV in the oncogenesis remains to be clarified, novel diagnostic and targeted therapeutic approaches are encouraging for the management of EBV-related malignancies. This review mainly focuses on the experimental and clinical advances of EBV-associated lymphoproliferative disorders. PMID:26628948

Oncogenic Human Papillomavirus: Application of CRISPR/Cas9 Therapeutic Strategies for Cervical Cancer

Directory of Open Access Journals (Sweden)

Shuai Zhen

2017-12-01

Full Text Available Oncogenic human papillomaviruses (HPVs cause different types of cancer especially cervical cancer. HPV-associated carcinogenesis provides a classical model system for clustered regularly interspaced short palindromic repeats (CRISPR/Cas9 based cancer therapies since the viral oncogenes E6 and E7 are exclusively expressed in cancerous cells. Sequence-specific gene knockdown/knockout using CRISPR/Cas9 shows promise as a novel therapeutic approach for the treatment of a variety of diseases that currently lack effective treatments. However, CRISPR/Cas9-based targeting therapy requires further validation of its efficacy in vitro and in vivo to eliminate the potential off-target effects, necessitates verification of the delivery vehicles and the combinatory use of conventional therapies with CRISPR/Cas9 to ensure the feasibility and safety. In this review we discuss the potential of combining CRISPR/Cas9 with other treatment options as therapies for oncogenic HPVs-associated carcinogenesis. and present our assessment of the promising path to the development of CRISPR/Cas9 therapeutic strategies for clinical settings.

Inhibition of Zika Virus Replication by Silvestrol

Directory of Open Access Journals (Sweden)

Fabian Elgner

2018-03-01

Full Text Available The Zika virus (ZIKV outbreak in 2016 in South America with specific pathogenic outcomes highlighted the need for new antiviral substances with broad-spectrum activities to react quickly to unexpected outbreaks of emerging viral pathogens. Very recently, the natural compound silvestrol isolated from the plant Aglaia foveolata was found to have very potent antiviral effects against the (−-strand RNA-virus Ebola virus as well as against Corona- and Picornaviruses with a (+-strand RNA-genome. This antiviral activity is based on the impaired translation of viral RNA by the inhibition of the DEAD-box RNA helicase eukaryotic initiation factor-4A (eIF4A which is required to unwind structured 5´-untranslated regions (5′-UTRs of several proto-oncogenes and thereby facilitate their translation. Zika virus is a flavivirus with a positive-stranded RNA-genome harboring a 5′-capped UTR with distinct secondary structure elements. Therefore, we investigated the effects of silvestrol on ZIKV replication in A549 cells and primary human hepatocytes. Two different ZIKV strains were used. In both infected A549 cells and primary human hepatocytes, silvestrol has the potential to exert a significant inhibition of ZIKV replication for both analyzed strains, even though the ancestor strain from Uganda is less sensitive to silvestrol. Our data might contribute to identify host factors involved in the control of ZIKV infection and help to develop antiviral concepts that can be used to treat a variety of viral infections without the risk of resistances because a host protein is targeted.

Oncogenic Notch signaling in T-cell and B-cell lymphoproliferative disorders.

Science.gov (United States)

Chiang, Mark Y; Radojcic, Vedran; Maillard, Ivan

2016-07-01

This article highlights recent discoveries about Notch activation and its oncogenic functions in lymphoid malignancies, and discusses the therapeutic potential of Notch inhibition. NOTCH mutations arise in a broad spectrum of lymphoid malignancies and are increasingly scrutinized as putative therapeutic targets. In T-cell acute lymphoblastic leukemia (T-ALL), NOTCH1 mutations affect the extracellular negative regulatory region and lead to constitutive Notch activation, although mutated receptors remain sensitive to Notch ligands. Other NOTCH1 mutations in T-ALL and NOTCH1/2 mutations in multiple B-cell malignancies truncate the C-terminal proline (P), glutamic acid (E), serine (S), threonine (T)-rich (PEST) domain, leading to decreased Notch degradation after ligand-mediated activation. Thus, targeting Notch ligand-receptor interactions could provide therapeutic benefits. In addition, we discuss recent reports on clinical testing of Notch inhibitors in T-ALL that influenced contemporary thinking on the challenges of targeting Notch in cancer. We review advances in the laboratory to address these challenges in regards to drug targets, the Notch-driven metabolome, and the sophisticated protein-protein interactions at Notch-dependent superenhancers that underlie oncogenic Notch functions. Notch signaling is a recurrent oncogenic pathway in multiple T- and B-cell lymphoproliferative disorders. Understanding the complexity and consequences of Notch activation is critical to define optimal therapeutic strategies targeting the Notch pathway.

Oncogenic osteomalacia presenting as bilateral stress fractures of the tibia

Energy Technology Data Exchange (ETDEWEB)

Ohashi, Kenjirou; Ohnishi, Takeshi; Ishikawa, Tohru [Department of Radiology, St. Marianna University Hospital, Kanagawa (Japan); Tani, Haruo [Department of Internal Medicine III, St. Marianna University Hospital, Kawasaki City, Kanagawa (Japan); Uesugi, Keisuke [Department of Otolaryngology, St. Marianna University Hospital, Kawasaki City, Kanagawa (Japan); Takagi, Masayuki [Department of Pathology, St. Marianna University Hospital, Kawasaki City, Kanagawa (Japan)

1999-01-01

We report on a patient with bilateral stress fractures of the tibia who subsequently showed classic biochemical features of oncogenic osteomalacia. Conventional radiographs were normal. MR imaging revealed symmetric, bilateral, band-like low-signal lesions perpendicular to the medial cortex of the tibiae and corresponding to the only lesions subsequently seen on the bone scan. A maxillary sinus lesion was subsequently detected and surgically removed resulting in prompt alleviation of symptoms and normalization of hypophosphatemia and low 1,25-(OH){sub 2} vitamin D{sub 3}. The lesion was pathologically diagnosed as a hemangiopericytoma-like tumor. Patients with oncogenic osteomalacia may present with stress fractures limited to the tibia, as seen in athletes. The clue to the real diagnosis lies in paying close attention to the serum phosphate levels, especially in patients suffering generalized symptoms of weakness and not given to unusual physical activity. (orig.) With 4 figs., 6 refs.

Genetic modelling of PIM proteins in cancer: proviral tagging, cooperation with oncogenes, tumor suppressor genes and carcinogens.

Directory of Open Access Journals (Sweden)

Enara eAguirre

2014-05-01

Full Text Available The PIM proteins, which were initially discovered as proviral insertion sites in Moloney murine leukemia virus infection, are a family of highly homologous serine/threonine kinases that have been reported to be overexpressed in hematological malignancies and solid tumors. The PIM proteins have also been associated with metastasis and overall treatment responses and implicated in the regulation of apoptosis, metabolism, the cell cycle, and homing and migration, which makes these proteins interesting targets for anticancer drug discovery. The use of retroviral insertional mutagenesis and refined approaches such as complementation tagging has allowed the identification of myc, pim and a third group of genes (including bmi1 and gfi1 as complementing genes in lymphomagenesis. Moreover, mouse modeling of human cancer has provided an understanding of the molecular pathways that are involved in tumor initiation and progression at the physiological level. In particular, genetically modified mice have allowed researchers to further elucidate the role of each of the Pim isoforms in various tumor types. PIM kinases have been identified as weak oncogenes because experimental overexpression in lymphoid tissue, prostate and liver induces tumors at a relatively low incidence and with a long latency. However, very strong synergistic tumorigenicity between Pim1/2 and c-Myc and other oncogenes has been observed in lymphoid tissues. Mouse models have also been used to study whether the inhibition of specific PIM isoforms is required to prevent carcinogen-induced sarcomas, indicating that the absence of Pim2 and Pim3 greatly reduces sarcoma growth and bone invasion; the extent of this effect is similar to that observed in the absence of all 3 isoforms. This review will summarize some of the animal models that have been used to understand the isoform-specific contribution of PIM kinases to tumorigenesis.

Virus como inductores de neoplasias cutáneas Viruses as agents inducing cutaneous neoplasms

Directory of Open Access Journals (Sweden)

Francisco Bravo Puccio

2013-03-01

Full Text Available El rol oncogénico de los virus en las neoplasias cutáneas es conocido por el hombre desde hace más de un siglo, cuando se atribuía el origen de la verruga vulgar al virus papiloma humano (VPH. En la actualidad, las neoplasias inducidas por virus pueden agruparse en tumores sólidos y procesos linfoproliferativos. Destacan entre los primeros el VPH, del cual ahora conocemos numerosos serotipos, cada uno vinculado a una neoplasia específica, el herpesvirus humano tipo 8 que produce el sarcoma de Kaposi y el poliomavirus vinculado al carcinoma de Merkel. Entre los procesos linfoproliferativos debemos mencionar al virus linfotrópico de células T humanas tipo 1 (HTLV-1 responsable de los linfomas de células T, en los cuales el compromiso cutáneo es inespecífico, con un amplio espectro de presentaciones clínicas y, que por consiguiente, plantean un reto para el diagnóstico diferencial. En este grupo también se encuentra el virus Epstein Barr vinculado a los linfomas nasales de Células NK/T y a los linfomas tipo Hidroa, de reciente descripción. En esta era en la que lo genético y lo molecular priman en las investigaciones en cáncer, no podemos dejar de lado el concepto de neoplasia como resultado de la infección por un agente viral, lo que abre una nueva veta de posibilidades de tratamiento anticanceroso basado en medicamentos antiviralesThe oncogenic role of viruses in cutaneous neoplasms has been known by humankind for more than a century, when the origin of the common wart, or verruca vulgaris, was attributed to the human papilloma virus (HPV. Currently, virus-induced cutaneous neoplasms may be grouped into solid tumors and lymphoproliferative disorders. HPV, from which various serotypes are now known, each being linked to a specific neoplasm, the human herpes virus type 8 producing Kaposi sarcoma, and the Merkel cell polyomavirus, highlight among the first group. Regarding the lymphoproliferative disorders, we should mention the

Niclosamide inhibits lytic replication of Epstein-Barr virus by disrupting mTOR activation.

Science.gov (United States)

Huang, Lu; Yang, Mengtian; Yuan, Yan; Li, Xiaojuan; Kuang, Ersheng

2017-02-01

Infection with the oncogenic γ-herpesviruses Epstein-Barr virus (EBV) and Kaposi's sarcoma-associated herpesvirus (KSHV) cause several severe malignancies in humans. Inhibition of the lytic replication of EBV and KSHV eliminates the reservoir of persistent infection and transmission, consequently preventing the occurrence of diseases from the sources of infection. Antiviral drugs are limited in controlling these viral infectious diseases. Here, we demonstrate that niclosamide, an old anthelmintic drug, inhibits mTOR activation during EBV lytic replication. Consequently, niclosamide effectively suppresses EBV lytic gene expression, viral DNA lytic replication and virion production in EBV-infected lymphoma cells and epithelial cells. Niclosamide exhibits cytotoxicity toward lymphoma cells and induces irreversible cell cycle arrest in lytically EBV-infected cells. The ectopic overexpression of mTOR reverses the inhibition of niclosamide in EBV lytic replication. Similarly, niclosamide inhibits KSHV lytic replication. Thus, we conclude that niclosamide is a promising candidate for chemotherapy against the acute occurrence and transmission of infectious diseases of oncogenic γ-herpesviruses. Copyright © 2016 Elsevier B.V. All rights reserved.

Human natural killer cells prevent infectious mononucleosis features by targeting lytic Epstein-Barr virus infection.

Science.gov (United States)

Chijioke, Obinna; Müller, Anne; Feederle, Regina; Barros, Mario Henrique M; Krieg, Carsten; Emmel, Vanessa; Marcenaro, Emanuela; Leung, Carol S; Antsiferova, Olga; Landtwing, Vanessa; Bossart, Walter; Moretta, Alessandro; Hassan, Rocio; Boyman, Onur; Niedobitek, Gerald; Delecluse, Henri-Jacques; Capaul, Riccarda; Münz, Christian

2013-12-26

Primary infection with the human oncogenic Epstein-Barr virus (EBV) can result in infectious mononucleosis (IM), a self-limiting disease caused by massive lymphocyte expansion that predisposes for the development of distinct EBV-associated lymphomas. Why some individuals experience this symptomatic primary EBV infection, whereas the majority acquires the virus asymptomatically, remains unclear. Using a mouse model with reconstituted human immune system components, we show that depletion of human natural killer (NK) cells enhances IM symptoms and promotes EBV-associated tumorigenesis mainly because of a loss of immune control over lytic EBV infection. These data suggest that failure of innate immune control by human NK cells augments symptomatic lytic EBV infection, which drives lymphocyte expansion and predisposes for EBV-associated malignancies. Copyright © 2013 The Authors. Published by Elsevier Inc. All rights reserved.

Deletion mutants of region E1 a of AD12 E1 plasmids: Effect on oncogenic transformation

NARCIS (Netherlands)

Bos, J.L.; Jochemsen, A.G.; Bernards, R.A.; Schrier, P.I.; Ormondt, H. van; Eb, A.J. van der

1983-01-01

Plasmids containing the El region of Ad12 DNA can transform certain rodent cells into oncogenic cells. To study the role of the Ela subregion in the process of oncogenic transformation, Ad12 region El mutants carrying deletions in the Ela region were constructed. Deletion mutants pR7 and pR8 affect

Oncogenic N-Ras Stimulates SRF-Mediated Transactivation via H3 Acetylation at Lysine 9

Directory of Open Access Journals (Sweden)

Sun-Ju Yi

2018-01-01

Full Text Available Signal transduction pathways regulate the gene expression by altering chromatin dynamics in response to mitogens. Ras proteins are key regulators linking extracellular stimuli to a diverse range of biological responses associated with gene regulation. In mammals, the three ras genes encode four Ras protein isoforms: H-Ras, K-Ras4A, K-Ras4B, and N-Ras. Although emerging evidence suggests that Ras isoforms differentially regulate gene expressions and are functionally nonredundant, the mechanisms underlying Ras specificity and Ras signaling effects on gene expression remain unclear. Here, we show that oncogenic N-Ras acts as the most potent regulator of SRF-, NF-κB-, and AP-1-dependent transcription. N-Ras-RGL2 axis is a distinct signaling pathway for SRF target gene expression such as Egr1 and JunB, as RGL2 Ras binding domain (RBD significantly impaired oncogenic N-Ras-induced SRE activation. By monitoring the effect of Ras isoforms upon the change of global histone modifications in oncogenic Ras-overexpressed cells, we discovered that oncogenic N-Ras elevates H3K9ac/H3K23ac levels globally in the chromatin context. Importantly, chromatin immunoprecipitation (ChIP assays revealed that H3K9ac is significantly enriched at the promoter and coding regions of Egr1 and JunB. Collectively, our findings define an undocumented role of N-Ras in modulating of H3 acetylation and in gene regulation.

Bilateral insufficiency fracture of the femoral head and neck in a case of oncogenic osteomalacia.

Science.gov (United States)

Chouhan, V; Agrawal, K; Vinothkumar, T K; Mathesul, A

2010-07-01

We describe a case of oncogenic osteomalacia in an adult male who presented with low back pain and bilateral hip pain. Extensive investigations had failed to find a cause. A plain pelvic radiograph showed Looser's zones in both femoral necks. MRI confirmed the presence of insufficiency fractures bilaterally in the femoral head and neck. Biochemical investigations confirmed osteomalacia which was unresponsive to treatment with vitamin D and calcium. A persistently low serum phosphate level suggested a diagnosis of hypophosphataemic osteomalacia. The level of fibroblast growth factor-23 was highly raised, indicating the cause as oncogenic osteomalacia. This was confirmed on positron-emission tomography, MRI and excision of a benign fibrous histiocytoma following a rapid recovery. The diagnosis of oncogenic osteomalacia may be delayed due to the non-specific presenting symptoms. Subchondral insufficiency fractures of the femoral head may be missed unless specifically looked for.

Oncogenes Activate an Autonomous Transcriptional Regulatory Circuit That Drives Glioblastoma

Directory of Open Access Journals (Sweden)

Dinesh K. Singh

2017-01-01

Full Text Available Efforts to identify and target glioblastoma (GBM drivers have primarily focused on receptor tyrosine kinases (RTKs. Clinical benefits, however, have been elusive. Here, we identify an SRY-related box 2 (SOX2 transcriptional regulatory network that is independent of upstream RTKs and capable of driving glioma-initiating cells. We identified oligodendrocyte lineage transcription factor 2 (OLIG2 and zinc-finger E-box binding homeobox 1 (ZEB1, which are frequently co-expressed irrespective of driver mutations, as potential SOX2 targets. In murine glioma models, we show that different combinations of tumor suppressor and oncogene mutations can activate Sox2, Olig2, and Zeb1 expression. We demonstrate that ectopic co-expression of the three transcription factors can transform tumor-suppressor-deficient astrocytes into glioma-initiating cells in the absence of an upstream RTK oncogene. Finally, we demonstrate that the transcriptional inhibitor mithramycin downregulates SOX2 and its target genes, resulting in markedly reduced proliferation of GBM cells in vivo.

Radiosensitivity and ras oncogene expression in preneoplastic rat tracheal epithelial cells

International Nuclear Information System (INIS)

Thomassen, D.G.; Wuensch, S.A.; Kelly, G.

1988-01-01

The sensitivity of preneoplastic rat tracheal epithelial (RTE) cells to the cytotoxic effects of high- and low-LET radiation, and the modulating effect of the viral ras oncogene on this sensitivity were determined. Two lines of preneoplastic RTE cells have the same responsiveness to high-LET radiation, but differ in their responsiveness to a transfected ras oncogene and in their sensitivities to low-LET radiation. Cells that respond to ras by becoming neoplastic are more resistant to the cytotoxic effects of low-LET radiation than cells that are not transformable by ras. The radiosensitivity of ras-responsive cells was not altered by transfection with ras. However, transfection of ras-non responsive cells with ras decreased their sensitivity to low-LET radiation. These data suggest that the ability of cells to repair radiation damage changes as they progress to neoplasia. (author)

Epstein-Barr virus: a master epigenetic manipulator.

Science.gov (United States)

Scott, Rona S

2017-10-01

Like all herpesviruses, the ability of Epstein-Barr virus (EBV) to establish life-long persistent infections is related to a biphasic viral lifecycle that involves latency and reactivation/lytic replication. Memory B cells serve as the EBV latency compartment where silencing of viral gene expression allows maintenance of the viral genome, avoidance of immune surveillance, and life-long carriage. Upon viral reactivation, viral gene expression is induced for replication, progeny virion production, and viral spread. EBV uses the host epigenetic machinery to regulate its distinct viral gene expression states. However, epigenetic manipulation by EBV affects the host epigenome by reprogramming cells in ways that leave long-lasting, oncogenic phenotypes. Such virally-induced epigenetic alterations are evident in EBV-associated cancers. Copyright © 2017 Elsevier B.V. All rights reserved.

Characterization of IKBKE as a Breast Cancer Oncogene

Science.gov (United States)

2011-10-01

HMLE -MEKDD cells stably expressing either pWZL or MF-IKKε. Immunoblot analysis by IKKε antibody. (D) IP with an IKK antibody from MCF-7 breast cancer ...summary is presented of research performed during three years of a project to further characterize the breast cancer oncogene IKKε. Two specific aims...constitutive IKKε transgenic mouse model to study the role of IKKε in breast cancer initiation and maintenance. The long term goals of this research

Proto-oncogene FBI-1 (Pokemon) and SREBP-1 Synergistically Activate Transcription of Fatty-acid Synthase Gene (FASN)*S⃞

Science.gov (United States)

Choi, Won-Il; Jeon, Bu-Nam; Park, Hyejin; Yoo, Jung-Yoon; Kim, Yeon-Sook; Koh, Dong-In; Kim, Myung-Hwa; Kim, Yu-Ri; Lee, Choong-Eun; Kim, Kyung-Sup; Osborne, Timothy F.; Hur, Man-Wook

2008-01-01

FBI-1 (Pokemon/ZBTB7A) is a proto-oncogenic transcription factor of the BTB/POZ (bric-à-brac, tramtrack, and broad complex and pox virus zinc finger) domain family. Recent evidence suggested that FBI-1 might be involved in adipogenic gene expression. Coincidentally, expression of FBI-1 and fatty-acid synthase (FASN) genes are often increased in cancer and immortalized cells. Both FBI-1 and FASN are important in cancer cell proliferation. SREBP-1 is a major regulator of many adipogenic genes, and FBI-1 and SREBP-1 (sterol-responsive element (SRE)-binding protein 1) interact with each other directly via their DNA binding domains. FBI-1 enhanced the transcriptional activation of SREBP-1 on responsive promoters, pGL2-6x(SRE)-Luc and FASN gene. FBI-1 and SREBP-1 synergistically activate transcription of the FASN gene by acting on the proximal GC-box and SRE/E-box. FBI-1, Sp1, and SREBP-1 can bind to all three SRE, GC-box, and SRE/E-box. Binding competition among the three transcription factors on the GC-box and SRE/E-box appears important in the transcription regulation. FBI-1 is apparently changing the binding pattern of Sp1 and SREBP-1 on the two elements in the presence of induced SREBP-1 and drives more Sp1 binding to the proximal promoter with less of an effect on SREBP-1 binding. The changes induced by FBI-1 appear critical in the synergistic transcription activation. The molecular mechanism revealed provides insight into how proto-oncogene FBI-1 may attack the cellular regulatory mechanism of FASN gene expression to provide more phospholipid membrane components needed for rapid cancer cell proliferation. PMID:18682402

Mutant p53 - heat shock response oncogenic cooperation: a new mechanism of cancer cell survival

Directory of Open Access Journals (Sweden)

Evguenia eAlexandrova

2015-04-01

Full Text Available The main tumor suppressor function of p53 as a ‘guardian of the genome’ is to respond to cellular stress by transcriptional activation of apoptosis, growth arrest or senescence in damaged cells. Not surprisingly, mutations in the p53 gene are the most frequent genetic alteration in human cancers. Importantly, mutant p53 (mutp53 proteins not only lose their wild-type tumor suppressor activity, but also can actively promote tumor development. Two main mechanisms accounting for mutp53 proto-oncogenic activity are inhibition of the wild-type p53 in a dominant-negative fashion and gain of additional oncogenic activities known as gain-of-function (GOF. Here we discuss a novel mechanism of mutp53 GOF, which relies on its oncogenic cooperation with the heat shock machinery. This coordinated adaptive mechanism renders cancer cells more resistant to proteotoxic stress and provides both, a strong survival advantage to cancer cells and a promising means for therapeutic intervention.

THE MYC FAMILY OF ONCOGENES AND THEIR PRESENCE AND IMPORTANCE IN SMALL-CELL LUNG-CARCINOMA AND OTHER TUMOR TYPES

NARCIS (Netherlands)

DEVRIES, EGE; MULDER, NH

1993-01-01

The myc family of cellular oncogenes, c - myr, N - myc, encodes three highly related, cell cycle specific, nuclear phosphoproteins. All are able to transform primary rat embryo fibroblasts when cotransfected with the c - ras oncogene. Myc family genes am differentially expressed with respect to

[HPV (Human Papilloma Virus) implication in other cancers than gynaecological].

Science.gov (United States)

Badoual, C; Tartour, E; Roussel, H; Bats, A S; Pavie, J; Pernot, S; Weiss, L; Mohamed, A Si; Thariat, J; Hoffmann, C; Péré, H

2015-08-01

Worldwide, approximately 5 to 10% of the population is infected by a Human Papilloma Virus (HPV). Some of these viruses, with a high oncogenic risk (HPV HR), are responsible for about 5% of cancer. It is now accepted that almost all carcinomas of the cervix and the vulva are due to an HPV HR (HPV16 and 18) infection. However, these viruses are known to be involved in the carcinogenesis of many other cancers (head and neck [SCCHN], penis, anus). For head and neck cancer, HPV infection is considered as a good prognostic factor. The role of HPV HR in anal cancer is also extensively studied in high-risk patient's population. The role of HPV infection in the carcinogenesis of esophageal, bladder, lung, breast or skin cancers is still debated. Given the multiple possible locations of HPV HR infection, the question of optimizing the management of patients with a HPV+ cancer arises in the implementation of a comprehensive clinical and biological monitoring. It is the same in therapeutics with the existence of a preventive vaccination, for example. Copyright © 2015 Société nationale française de médecine interne (SNFMI). Published by Elsevier SAS. All rights reserved.

Infektion mit Epstein-Barr-Virus und Tumor-Entstehung beim Menschen

Science.gov (United States)

Kirchner, H.

1981-08-01

The Epstein-Barr Virus (EBV) is the only infectious agent for which a close association with human malignant tumors has been clearly demonstrated. These tumors are one type of nasopharyngeal carcinoma which is frequent in parts of East Asia and the Burkitt lymphoma which predominantly occurs in parts of Africa and New Guinea. Nonetheless, the EBV is the causative agent of infectious mononucleosis (IM), a benign, self-limiting lymphoproliferative disease of adolescents. The major difference between the countries in which the EBV-induced tumors occur and those in which IM occurs is the late primary EBV infection in the latter, whereas primary infection with EBV occurs in the first year of life in the former. All theories of viral carcinogenesis have to explain the long latency period between primary infection and tumor growth and how an ubiquitous virus may be oncogenic. Thus, invariably, one has to assume a role of cofactors, which may be of cytogenetic nature or may be represented by additional infections or by chemical agents. Since most modern theories of carcinogenesis consider a multi-step development of tumors, the theory that infection with an ubiquitous virus at the right time of life represents one step to carcinogenesis seems to be tenable.

An overview of triple infection with hepatitis B, C and D viruses.

Science.gov (United States)

Riaz, Mehwish; Idrees, Muhamad; Kanwal, Hifza; Kabir, Firoz

2011-07-27

Viral hepatitis is one of the major health problems worldwide, particularly in South East Asian countries including Pakistan where hepatitis C virus (HCV) and hepatitis B virus (HBV) infections are highly endemic. Hepatitis delta virus (HDV) is also not uncommon world-wide. HCV, HBV, and HDV share parallel routes of transmission due to which dual or triple viral infection can occur in a proportion of patients at the same time. HBV and HCV are important factors in the development of liver cirrhosis (LC) and hepatocellular carcinoma (HCC). In addition to LC and HCC, chronic HDV infection also plays an important role in liver damage with oncogenic potential.The current article reviews the available literature about the epidemiology, pathogenesis, transmission, symptoms, diagnosis, replication, disease outcome, treatment and preventive measures of triple hepatitis infection by using key words; epidemiology of triple infection, risk factors, awareness status, treatment and replication cycle in PubMed, PakMediNet, Directory of Open Access Journals (DOAJ) and Google Scholar. Total data from 74 different studies published from 1983 to 2010 on triple hepatitis infections were reviewed and included in this study. The present article briefly describes triple infection with HCV, HBV and HDV.

Differential p53 engagement in response to oxidative and oncogenic stresses in Fanconi anemia mice

OpenAIRE

Rani, Reena; Li, Jie; Pang, Qishen

2008-01-01

Members of the Fanconi anemia (FA) protein family are involved in repair of genetic damage caused by DNA cross-linkers. It is not clear whether the FA proteins function in oxidative DNA damage and oncogenic stress response. Here we report that deficiency in the Fanca gene in mice elicits a p53-dependent growth arrest and DNA damage response to oxidative DNA damage and oncogenic stress. Using a Fanca-/- Trp53-/- double knockout model and a functionally switchable p53 retrovirus, we define the ...

Prevention of EBV lymphoma development by oncolytic myxoma virus in a murine xenograft model of post-transplant lymphoproliferative disease

Energy Technology Data Exchange (ETDEWEB)

Kim, Manbok, E-mail: manbok66@dankook.ac.kr [Department of Molecular Genetics and Microbiology, University of Florida, Gainesville, FL 32610 (United States); Rahman, Masmudur M. [Department of Molecular Genetics and Microbiology, University of Florida, Gainesville, FL 32610 (United States); Cogle, Christopher R. [Department of Hematology/Oncology, University of Florida, Gainesville, FL 32610 (United States); McFadden, Grant [Department of Molecular Genetics and Microbiology, University of Florida, Gainesville, FL 32610 (United States)

2015-07-10

Epstein–Barr virus (EBV) has been associated with a variety of epithelial and hematologic malignancies, including B-, T- and NK cell-lymphomas, Hodgkin's disease (HD), post-transplant lymphoproliferative diseases (LPDs), nasopharyngeal and gastric carcinomas, smooth muscle tumors, and HIV-associated lymphomas. Currently, treatment options for EBV-associated malignancies are limited. We have previously shown that myxoma virus specifically targets various human solid tumors and leukemia cells in a variety of animal models, while sparing normal human or murine tissues. Since transplant recipients of bone marrow or solid organs often develop EBV-associated post-transplant LPDs and lymphoma, myxoma virus may be of utility to prevent EBV-associated malignancies in immunocompromised transplant patients where treatment options are frequently limited. In this report, we demonstrate the safety and efficacy of myxoma virus purging as a prophylactic strategy for preventing post-transplant EBV-transformed human lymphomas, using a highly immunosuppressed mouse xenotransplantation model. This provides support for developing myxoma virus as a potential oncolytic therapy for preventing EBV-associated LPDs following transplantation of bone marrow or solid organ allografts. - Highlights: • Myxoma virus effectively infects and purges EBV lymphoma cells in vivo. • Oncolytic myxoma virus effectively eradicates oncogenic EBV tumorigenesis. • Ex vivo pre-treatment of myxoma virus can be effective as a preventive treatment modality for post-transplant lymphoproliferative diseases.

Prevention of EBV lymphoma development by oncolytic myxoma virus in a murine xenograft model of post-transplant lymphoproliferative disease

International Nuclear Information System (INIS)

Kim, Manbok; Rahman, Masmudur M.; Cogle, Christopher R.; McFadden, Grant

2015-01-01

Epstein–Barr virus (EBV) has been associated with a variety of epithelial and hematologic malignancies, including B-, T- and NK cell-lymphomas, Hodgkin's disease (HD), post-transplant lymphoproliferative diseases (LPDs), nasopharyngeal and gastric carcinomas, smooth muscle tumors, and HIV-associated lymphomas. Currently, treatment options for EBV-associated malignancies are limited. We have previously shown that myxoma virus specifically targets various human solid tumors and leukemia cells in a variety of animal models, while sparing normal human or murine tissues. Since transplant recipients of bone marrow or solid organs often develop EBV-associated post-transplant LPDs and lymphoma, myxoma virus may be of utility to prevent EBV-associated malignancies in immunocompromised transplant patients where treatment options are frequently limited. In this report, we demonstrate the safety and efficacy of myxoma virus purging as a prophylactic strategy for preventing post-transplant EBV-transformed human lymphomas, using a highly immunosuppressed mouse xenotransplantation model. This provides support for developing myxoma virus as a potential oncolytic therapy for preventing EBV-associated LPDs following transplantation of bone marrow or solid organ allografts. - Highlights: • Myxoma virus effectively infects and purges EBV lymphoma cells in vivo. • Oncolytic myxoma virus effectively eradicates oncogenic EBV tumorigenesis. • Ex vivo pre-treatment of myxoma virus can be effective as a preventive treatment modality for post-transplant lymphoproliferative diseases

Engineering and Functional Characterization of Fusion Genes Identifies Novel Oncogenic Drivers of Cancer. | Office of Cancer Genomics

Science.gov (United States)

Oncogenic gene fusions drive many human cancers, but tools to more quickly unravel their functional contributions are needed. Here we describe methodology permitting fusion gene construction for functional evaluation. Using this strategy, we engineered the known fusion oncogenes, BCR-ABL1, EML4-ALK, and ETV6-NTRK3, as well as 20 previously uncharacterized fusion genes identified in TCGA datasets.

Oncogene activation and surface markers in mouse lymphomas induced by radiation and nitrosomethylurea

Energy Technology Data Exchange (ETDEWEB)

Guerrero, I.; Villasante, A.; Diamond, L.; Berman, J.W.; Newcomb, E.W.; Steinberg, J.J.; Lake, R.; Pellicer, A.

1986-01-01

Thymic lymphomas have been induced by ..gamma..-radiation and treatment with the chemical nitrosomethylurea in different mice strains. As indicated by the NIH 3T3 focus forming assay, a significant percentage of the tumors contain activated oncogenes of the ras family (K or N). Cloning and sequencing has enabled us to identify single base mutations as the only significant alteration present in the activated oncogenes. These alterations result in the substitution of amino-acid 12 or 61 of the p21 product of the ras genes. With the use of synthetic oligonucleotides it has been found that the tumors do not all contain the same mutation and in one case so far the normal allele is absent.

Human papilloma virus, herpes simplex virus and epstein barr virus in oral squamous cell carcinoma from eight different countries.

Science.gov (United States)

Jalouli, Jamshid; Jalouli, Miranda M; Sapkota, Dipak; Ibrahim, Salah O; Larsson, Per-Anders; Sand, Lars

2012-02-01

Oral squamous cell carcinoma (OSCC) is a major health problem in many parts of the world, and the major causative agents are thought to be the use of alcohol and tobacco. Oncogenic viruses have also been suggested to be involved in OSCC development. This study investigated the prevalence of human papillomaviruses (HPV), herpes simplex virus (HSV) and Epstein-Barr virus (EBV) in 155 OSCC from eight different countries from different ethnic groups, continents and with different socioeconomic backgrounds. 41 A total of OSCCs were diagnosed in the tongue (26%) and 23 in the floor of the mouth (15%); the other 91 OSCCs were diagnosed in other locations (59%). The patients were also investigated regarding the use of alcohol and smoking and smokeless tobacco habits. Tissue samples were obtained from formalin-fixed, paraffin-embedded samples of the OSCC. DNA was extracted and the viral genome was examined by single, nested and semi-nested PCR assays. Sequencing of double-stranded DNA from the PCR product was carried out. Following sequencing of the HPV-, HSV- and EBV-positive PCR products, 100% homology between the sampels was found. Of all the 155 OSCCs examined, 85 (55%) were positive for EBV, 54 (35%) for HPV and 24 (15%) for HSV. The highest prevalence of HPV was seen in Sudan (65%), while HSV (55%) and EBV (80%) were most prevalent in the UK. In 34% (52/155) of all the samples examined, co-infection by two (46/155=30%) or three (6/155=4%) virus specimens was detected. The most frequent double infection was HPV with EBV in 21% (32/155) of all OSCCs. There was a statistically significant higher proportion of samples with HSV (p=0.026) and EBV (p=0.015) in industrialized countries (Sweden, Norway, UK and USA) as compared to developing countries (Sudan, India, Sri Lanka and Yemen). Furthermore, there was a statistically significant higher co-infection of HSV and EBV in samples from industrialized countries (p=0.00031). No firm conclusions could be drawn regarding the

Detection of Active Epstein-Barr Virus Infection in Duodenal Mucosa of Patients With Refractory Celiac Disease.

Science.gov (United States)

Perfetti, Vittorio; Baldanti, Fausto; Lenti, Marco Vincenzo; Vanoli, Alessandro; Biagi, Federico; Gatti, Marta; Riboni, Roberta; Dallera, Elena; Paulli, Marco; Pedrazzoli, Paolo; Corazza, Gino Roberto

2016-08-01

Refractory celiac disease is characterized by mucosal damage in patients with celiac disease despite a gluten-free diet. Little is known about the mechanisms that cause persistent intestinal inflammation in these patients. We performed a case-control study of 17 consecutive patients diagnosed with refractory celiac disease from 2001 through 2014 (median age, 51 y; 10 women) and 24 patients with uncomplicated celiac disease (controls) to determine whether refractory disease is associated with infection by lymphotropic oncogenic viruses. We performed real-time PCR analyses of duodenal biopsy samples from all patients to detect Epstein-Barr virus (EBV), human herpesvirus-8, and human T-cell lymphotropic virus-I, -II, or -III. We used in situ hybridization and immunohistochemical analyses to identify infected cells and viral proteins. We did not detect human herpesvirus-8 or human T-cell lymphotropic viruses in any of the biopsy specimens. However, 12 of 17 (70.5%) biopsy specimens from patients with refractory celiac disease were positive for EBV, compared with 4 of 24 (16.6%) biopsy specimens from controls (P disease and enteropathy-associated T-cell lymphoma. Copyright © 2016 AGA Institute. Published by Elsevier Inc. All rights reserved.

Multistep process of neoplastic transformation of normal human fibroblasts by 60Co gamma rays and Harvey sarcoma viruses

Energy Technology Data Exchange (ETDEWEB)

Namba, M.; Nishitani, K.; Fukushima, F.; Kimoto, T.; Nose, K.

1986-03-15

As reported previously (Namba et al., 1985), normal human fibroblasts were transformed by 60Co gamma-ray irradiation into immortal cells with abnormal karyotypes. These transformed cells (KMST-6), however, showed a low cloning efficiency in soft agar and no transplantability. However, upon treatment with Harvey murine sarcoma virus (Ha-MSV), the cells acquired elevated clonability in soft agar and transplantability in nude mice. Ha-MSV alone, however, did not convert normal human fibroblasts into either immortal or tumorigenic cells. The Ha-MSV-transformed KMST-6 cells showed an enhanced expression of the ras oncogene, but normal and 60Co gamma-ray-transformed cells did not. Our current data suggest that gamma rays worked against normal human cells as an initiator, giving rise to chromosome aberrations and immortality, and that Ha-MSV, probably through its ras oncogene, played a role in the progression of the malignant cell population to a more malignant one showing enhanced colony formation in soft agar and tumorigenicity in nude mice.

Aging-associated inflammation promotes selection for adaptive oncogenic events in B cell progenitors.

Science.gov (United States)

Henry, Curtis J; Casás-Selves, Matias; Kim, Jihye; Zaberezhnyy, Vadym; Aghili, Leila; Daniel, Ashley E; Jimenez, Linda; Azam, Tania; McNamee, Eoin N; Clambey, Eric T; Klawitter, Jelena; Serkova, Natalie J; Tan, Aik Choon; Dinarello, Charles A; DeGregori, James

2015-12-01

The incidence of cancer is higher in the elderly; however, many of the underlying mechanisms for this association remain unexplored. Here, we have shown that B cell progenitors in old mice exhibit marked signaling, gene expression, and metabolic defects. Moreover, B cell progenitors that developed from hematopoietic stem cells (HSCs) transferred from young mice into aged animals exhibited similar fitness defects. We further demonstrated that ectopic expression of the oncogenes BCR-ABL, NRAS(V12), or Myc restored B cell progenitor fitness, leading to selection for oncogenically initiated cells and leukemogenesis specifically in the context of an aged hematopoietic system. Aging was associated with increased inflammation in the BM microenvironment, and induction of inflammation in young mice phenocopied aging-associated B lymphopoiesis. Conversely, a reduction of inflammation in aged mice via transgenic expression of α-1-antitrypsin or IL-37 preserved the function of B cell progenitors and prevented NRAS(V12)-mediated oncogenesis. We conclude that chronic inflammatory microenvironments in old age lead to reductions in the fitness of B cell progenitor populations. This reduced progenitor pool fitness engenders selection for cells harboring oncogenic mutations, in part due to their ability to correct aging-associated functional defects. Thus, modulation of inflammation--a common feature of aging--has the potential to limit aging-associated oncogenesis.

Energy parasites trigger oncogene mutation.

Science.gov (United States)

Pokorný, Jiří; Pokorný, Jan; Jandová, Anna; Kobilková, Jitka; Vrba, Jan; Vrba, Jan

2016-10-01

Cancer initialization can be explained as a result of parasitic virus energy consumption leading to randomized genome chemical bonding. Analysis of experimental data on cell-mediated immunity (CMI) containing about 12,000 cases of healthy humans, cancer patients and patients with precancerous cervical lesions disclosed that the specific cancer and the non-specific lactate dehydrogenase-elevating (LDH) virus antigen elicit similar responses. The specific antigen is effective only in cancer type of its origin but the non-specific antigen in all examined cancers. CMI results of CIN patients display both healthy and cancer state. The ribonucleic acid (RNA) of the LDH virus parasitizing on energy reduces the ratio of coherent/random oscillations. Decreased effect of coherent cellular electromagnetic field on bonding electrons in biological macromolecules leads to elevating probability of random genome reactions. Overlapping of wave functions in biological macromolecules depends on energy of the cellular electromagnetic field which supplies energy to bonding electrons for selective chemical bonds. CMI responses of cancer and LDH virus antigens in all examined healthy, precancerous and cancer cases point to energy mechanism in cancer initiation. Dependence of the rate of biochemical reactions on biological electromagnetic field explains yet unknown mechanism of genome mutation.

Prostate-derived Ets factor, an oncogenic driver in breast cancer.

Science.gov (United States)

Sood, Ashwani K; Geradts, Joseph; Young, Jessica

2017-05-01

Prostate-derived Ets factor (PDEF), a member of the Ets family of transcription factors, differs from other family members in its restricted expression in normal tissues and its unique DNA-binding motif. These interesting attributes coupled with its aberrant expression in cancer have rendered PDEF a focus of increasing interest by tumor biologists. This review provides a current understanding of the characteristics of PDEF expression and its role in breast cancer. The bulk of the evidence is consistent with PDEF overexpression in most breast tumors and an oncogenic role for this transcription factor in breast cancer. In addition, high PDEF expression in estrogen receptor-positive breast tumors showed significant correlation with poor overall survival in several independent cohorts of breast cancer patients. Together, these findings demonstrate PDEF to be an oncogenic driver of breast cancer and a biomarker of poor prognosis in this cancer. Based on this understanding and the limited expression of PDEF in normal human tissues, the development of PDEF-based therapeutics for prevention and treatment of breast cancer is also discussed.

G.I.S. Surveillance of Chronic Non-occupational Exposure to Heavy Metals as Oncogenic Risk

Directory of Open Access Journals (Sweden)

Mariana Vlad

2016-02-01

Full Text Available Introduction: The potential oncogenic effect of some heavy metals in people occupationally and non-occupationally exposed to such heavy metals is already well demonstrated. This study seeks to clarify the potential role of these heavy metals in the living environment, in this case in non-occupational multifactorial aetiology of malignancies in the inhabitants of areas with increased prevalent environmental levels of heavy metals. Methods: Using a multidisciplinary approach throughout a complex epidemiological study, we investigated the potential oncogenic role of non-occupational environmental exposure to some heavy metals [chrome (Cr, nickel (Ni, copper (Cu, zinc (Zn, cadmium (Cd, lead (Pb and arsenic (As—in soil, drinking water, and food, as significant components of the environment] in populations living in areas with different environmental levels (high vs. low of the above-mentioned heavy metals. The exposures were evaluated by identifying the exposed populations, the critical elements of the ecosystems, and as according to the means of identifying the types of exposure. The results were interpreted both epidemiologically (causal inference, statistical significance, mathematical modelling and by using a GIS approach, which enabled indirect surveillance of oncogenic risks in each population. Results: The exposure to the investigated heavy metals provides significant risk factors of cancer in exposed populations, in both urban and rural areas [χ² test (p < 0.05]. The GIS approach enables indirect surveillance of oncogenic risk in populations. Conclusions: The role of non-occupational environmental exposure to some heavy metals in daily life is among the more significant oncogenic risk factors in exposed populations. The statistically significant associations between environmental exposure to such heavy metals and frequency of neoplasia in exposed populations become obvious when demonstrated on maps using the GIS system. Environmental

Pim kinases are upregulated during Epstein-Barr virus infection and enhance EBNA2 activity

International Nuclear Information System (INIS)

Rainio, Eeva-Marja; Ahlfors, Helena; Carter, Kara L.; Ruuska, Marja; Matikainen, Sampsa; Kieff, Elliott; Koskinen, Paeivi J.

2005-01-01

Latent Epstein-Barr virus (EBV) infection is strongly associated with B-cell proliferative diseases such as Burkitt's lymphoma. Here we show that the oncogenic serine/threonine kinases Pim-1 and Pim-2 enhance the activity of the viral transcriptional activator EBNA2. During EBV infection of primary B-lymphocytes, the mRNA expression levels of pim genes, especially of pim-2, are upregulated and remain elevated in latently infected B-cell lines. Thus, EBV-induced upregulation of Pim kinases and Pim-stimulated EBNA2 transcriptional activity may contribute to the ability of EBV to immortalize B-cells and predispose them to malignant growth

Polymerase chain reaction-based detection of myc transduction in feline leukemia virus-infected cats.

Science.gov (United States)

Sumi, Ryosuke; Miyake, Ariko; Endo, Taiji; Ohsato, Yoshiharu; Ngo, Minh Ha; Nishigaki, Kazuo

2018-04-01

Feline lymphomas are associated with the transduction and activation of cellular proto-oncogenes, such as c-myc, by feline leukemia virus (FeLV). We describe a polymerase chain reaction assay for detection of myc transduction usable in clinical diagnosis. The assay targets c-myc exons 2 and 3, which together result in a FeLV-specific fusion gene following c-myc transduction. When this assay was conducted on FeLV-infected feline tissues submitted for clinical diagnosis of tumors, myc transduction was detected in 14% of T-cell lymphoma/leukemias. This newly established system could become a useful diagnostic tool in veterinary medicine.

The Homeodomain Transcription Factor Cdx1 Does Not Behave as an Oncogene in Normal Mouse Intestine

Directory of Open Access Journals (Sweden)

Mary Ann S. Crissey

2008-01-01

Full Text Available The Caudal-related homeobox genes Cdx1 and Cdx2 are intestine-specific transcription factors that regulate differentiation of intestinal cell types. Previously, we have shown Cdx1 to be antiproliferative and to promote cell differentiation. However, other studies have suggested that Cdx1 may be an oncogene. To test for oncogenic behavior, we used the murine villin promoter to ectopically express Cdx1 in the small intestinal villi and colonic surface epithelium. No changes in intestinal architecture, cell differentiation, or lineage selection were observed with expression of the transgene. Classic oncogenes enhance proliferation and induce tumors when ectopically expressed. However, the Cdx1 transgene neither altered intestinal proliferation nor induced spontaneous intestinal tumors. In a murine model for colitis-associated cancer, the Cdx1 transgene decreased, rather than increased, the number of adenomas that developed. In the polyps, the expression of the endogenous and the transgenic Cdx1 proteins was largely absent, whereas endogenous Villin expression was retained. This suggests that transgene silencing was specific and not due to a general Villin inactivation. In conclusion, neither the ectopic expression of Cdx1 was associated with changes in intestinal cell proliferation or differentiation nor was there increased intestinal cancer susceptibility. Our results therefore suggest that Cdx1 is not an oncogene in normal intestinal epithelium.

Assessment of differential expression of oncogenes in adenocarcinoma of stomach with fluorescent labeling and simultaneous amplification of gene transcripts

International Nuclear Information System (INIS)

Rajcevic, U.; Hudler, P.; Komel, R.; Mijovski, G.; Gorjanc, G.; Kovac, M.; Hoelzl, G.; Repse, S.; Juvan, R.; Huber, C.G.

2007-01-01

Background. Gastric cancer is one of the leading malignancies with a poor prognosis and low survival rates. Although the mechanisms underlying its development are still unknown, there is a consensus that genetic instability, inactivation of tumor suppressor genes and over-expression of oncogenes are involved in the early and late stages of gastric carcinogenesis. In the present study we wanted to display differential expression of seven oncogenes, namely CCNE1, EGF, ERBB3, FGF4, HRG1, HGFR and TDGF1. Patients and methods. We employed a method based on the multiplex reverse transcription polymerase chain (RT-PCR) method with a fluorescence detection. Results. More than half of patients (74.3%) out of total 74 with gastric adenocarcinoma had over-expressed at least one oncogene, with the exception of FGF4, which was expressed in tumor tissue of less than one third of patients. 56.8% of the patients patients showed over-expression of two or more oncogenes. Conclusions. Patients with precancerous lesions had elevated levels of TDGF1 or cripto-1 (64.9%) and CCNE1 (57.1%), suggesting that they could be used as markers for an early detection of malignant changes in stomach. Finally, the fluorescent multiplex RT-PCR method could be of value for rapid assessment of oncogene mRNA levels in small samples of tumor or precancerous biopsies. (author)

Oncogenic ras-driven cancer cell vesiculation leads to emission of double-stranded DNA capable of interacting with target cells

International Nuclear Information System (INIS)

Lee, Tae Hoon; Chennakrishnaiah, Shilpa; Audemard, Eric; Montermini, Laura; Meehan, Brian; Rak, Janusz

2014-01-01

Highlights: • Oncogenic H-ras stimulates emission of extracellular vesicles containing double-stranded DNA. • Vesicle-associated extracellular DNA contains mutant N-ras sequences. • Vesicles mediate intercellular transfer of mutant H-ras DNA to normal fibroblasts where it remains for several weeks. • Fibroblasts exposed to vesicles containing H-ras DNA exhibit increased proliferation. - Abstract: Cell free DNA is often regarded as a source of genetic cancer biomarkers, but the related mechanisms of DNA release, composition and biological activity remain unclear. Here we show that rat epithelial cell transformation by the human H-ras oncogene leads to an increase in production of small, exosomal-like extracellular vesicles by viable cancer cells. These EVs contain chromatin-associated double-stranded DNA fragments covering the entire host genome, including full-length H-ras. Oncogenic N-ras and SV40LT sequences were also found in EVs emitted from spontaneous mouse brain tumor cells. Disruption of acidic sphingomyelinase and the p53/Rb pathway did not block emission of EV-related oncogenic DNA. Exposure of non-transformed RAT-1 cells to EVs containing mutant H-ras DNA led to the uptake and retention of this material for an extended (30 days) but transient period of time, and stimulated cell proliferation. Thus, our study suggests that H-ras-mediated transformation stimulates vesicular emission of this histone-bound oncogene, which may interact with non-transformed cells

Oncogenic ras-driven cancer cell vesiculation leads to emission of double-stranded DNA capable of interacting with target cells

Energy Technology Data Exchange (ETDEWEB)

Lee, Tae Hoon; Chennakrishnaiah, Shilpa [Montreal Children’s Hospital, Research Institute of McGill University Health Centre, McGill University, Montreal, Quebec (Canada); Audemard, Eric [McGill University and Genome Quebec Innovation Centre, Montreal, Quebec (Canada); Montermini, Laura; Meehan, Brian [Montreal Children’s Hospital, Research Institute of McGill University Health Centre, McGill University, Montreal, Quebec (Canada); Rak, Janusz, E-mail: janusz.rak@mcgill.ca [Montreal Children’s Hospital, Research Institute of McGill University Health Centre, McGill University, Montreal, Quebec (Canada)

2014-08-22

Highlights: • Oncogenic H-ras stimulates emission of extracellular vesicles containing double-stranded DNA. • Vesicle-associated extracellular DNA contains mutant N-ras sequences. • Vesicles mediate intercellular transfer of mutant H-ras DNA to normal fibroblasts where it remains for several weeks. • Fibroblasts exposed to vesicles containing H-ras DNA exhibit increased proliferation. - Abstract: Cell free DNA is often regarded as a source of genetic cancer biomarkers, but the related mechanisms of DNA release, composition and biological activity remain unclear. Here we show that rat epithelial cell transformation by the human H-ras oncogene leads to an increase in production of small, exosomal-like extracellular vesicles by viable cancer cells. These EVs contain chromatin-associated double-stranded DNA fragments covering the entire host genome, including full-length H-ras. Oncogenic N-ras and SV40LT sequences were also found in EVs emitted from spontaneous mouse brain tumor cells. Disruption of acidic sphingomyelinase and the p53/Rb pathway did not block emission of EV-related oncogenic DNA. Exposure of non-transformed RAT-1 cells to EVs containing mutant H-ras DNA led to the uptake and retention of this material for an extended (30 days) but transient period of time, and stimulated cell proliferation. Thus, our study suggests that H-ras-mediated transformation stimulates vesicular emission of this histone-bound oncogene, which may interact with non-transformed cells.

The PDZ domain binding motif (PBM) of human T-cell leukemia virus type 1 Tax can be substituted by heterologous PBMs from viral oncoproteins during T-cell transformation.

Science.gov (United States)

Aoyagi, Tomoya; Takahashi, Masahiko; Higuchi, Masaya; Oie, Masayasu; Tanaka, Yuetsu; Kiyono, Tohru; Aoyagi, Yutaka; Fujii, Masahiro

2010-04-01

Several tumor viruses, such as human T-cell leukemia virus (HTLV), human papilloma virus (HPV), human adenovirus, have high-oncogenic and low-oncogenic subtypes, and such subtype-specific oncogenesis is associated with the PDZ-domain binding motif (PBM) in their transforming proteins. HTLV-1, the causative agent of adult T-cell leukemia, encodes Tax1 with PBM as a transforming protein. The Tax1 PBM was substituted with those from other oncoviruses, and the transforming activity was examined. Tax1 mutants with PBM from either HPV-16 E6 or adenovirus type 9 E4ORF1 are fully active in the transformation of a mouse T-cell line from interleukin-2-dependent growth into independent growth. Interestingly, one such Tax1 PBM mutant had an extra amino acid insertion derived from E6 between PBM and the rest of Tax1, thus suggesting that the amino acid sequences of the peptides between PBM and the rest of Tax1 and the numbers only slightly affect the function of PBM in the transformation. Tax1 and Tax1 PBM mutants interacted with tumor suppressors Dlg1 and Scribble with PDZ-domains. Unlike E6, Tax1 PBM mutants as well as Tax1 did not or minimally induced the degradations of Dlg1 and Scribble, but instead induced their subcellular translocation from the detergent-soluble fraction into the insoluble fraction, thus suggesting that the inactivation mechanism of these tumor suppressor proteins is distinct. The present results suggest that PBMs of high-risk oncoviruses have a common function(s) required for these three tumor viruses to transform cells, which is likely associated with the subtype-specific oncogenesis of these tumor viruses.

The oncogenic action of ionizing radiation on rat skin: Progress report, February 1, 1988-January 31, 1989

International Nuclear Information System (INIS)

Burns, F.J.; Garte, S.J.

1988-01-01

Progress is described in 3 general areas corresponding to the specific aims of the proposal, including DNA strand breaks in the epidermis as a function of radiation penetration; oncogene activation in radiation-induced rat skin cancers; and carcinogenesis in rat skin induced by the neon ion beam. Numerous experiments have established that DNA strand breaks per unit dose in the rat epidermis are reduced by about 60% when the radiation penetration is reduced from 1.0 mm to 0.2 mm. The activation of oncogenes in the radiation-induced rat skin cancers followed a pattern. Four highly malignant cancers exhibited activation of K-ras and c-myc oncogenes, while the remaining 8 cancers exhibited only one or the other of these 2 oncogenes. Of 5 squamous carcinomas, 4 showed K-ras activation and 1 showed c-myc activation. Approximately 200 rats were exposed to the neon ion beam at the Bevalac in Berkeley, CA. The carcinogenicity of energetic electrons (2.0 MeV) was determined in conjunction with the neon ion experiment. It is too early to evaluate tumor incidence in the neon ion experiment, but for electrons an unusually large excess of connective tissue tumors, fibromas and sarcomas, have been observed so far. 59 refs., 2 tabs

Oncogene Mimicry as a Mechanism of Primary Resistance to BRAF Inhibitors

Directory of Open Access Journals (Sweden)

Martin L. Sos

2014-08-01

Full Text Available Despite the development of potent RAF/mitogen-activated protein kinase (MAPK pathway inhibitors, only a fraction of BRAF-mutant patients benefit from treatment with these drugs. Using a combined chemogenomics and chemoproteomics approach, we identify drug-induced RAS-RAF-MEK complex formation in a subset of BRAF-mutant cancer cells characterized by primary resistance to vemurafenib. In these cells, autocrine interleukin-6 (IL-6 secretion may contribute to the primary resistance phenotype via induction of JAK/STAT3 and MAPK signaling. In a subset of cell lines, combined IL-6/MAPK inhibition is able to overcome primary resistance to BRAF-targeted therapy. Overall, we show that the signaling plasticity exerted by primary resistant BRAF-mutant cells is achieved by their ability to mimic signaling features of oncogenic RAS, a strategy that we term “oncogene mimicry.” This model may guide future strategies for overcoming primary resistance observed in these tumors.

Fused pyrazine mono-N-oxides as bioreductive drugs. II cytotoxicity in human cells and oncogenicity in a rodent transformation assay

International Nuclear Information System (INIS)

Langmuir, Virginia K.; Laderoute, Keith R.; Mendonca, Holly L.; Sutherland, Robert M.; Hei, Tom K.; Liu, S.-X.; Hall, Eric J.; Naylor, Matthew A.; Adams, Gerald E.

1996-01-01

Purpose: To determine what structural moieties of the fused pyrazine mono-N-oxides are determining factors in their in vitro cytotoxicity and oncogenicity. Methods and Materials: A new series of experimental bioreductive drugs, fused pyrazine mono-N-oxides, was evaluated in vitro for aerobic and hypoxic cytotoxicity in the HT29 human colon adenocarcinoma cell line by using clonogenic assays. The relative oncogenicities of these compounds were also determined in aerobic cultures of C3H 10T1/2 mouse embryo fibroblasts by using a standard transformation assay. Results: Removal of the 4-methyl piperazine side chain from the parent compound, RB 90740, reduced the potency of the hypoxic cytotoxin. Reduction of the N-oxide function increased the aerobic cytotoxicity and eliminated most of the hypoxic/aerobic cytotoxic differential. The reduced N-oxide also had significant oncogenicity, consistent with a mechanism of genotoxicity following bioreduction of RB 90740. Conclusion: This new series of bioreductive compounds may be effective in cancer therapy, particularly the lead compound RB 90740. The oncogenic potential of these compounds is similar to that for other cancer therapies. Further studies should include evaluation of these compounds in vivo and the development of analogs with reduced oncogenic potential and retention of the hypoxic/aerobic cytotoxicity differential

Multiple fractions of gamma rays do not induce overexpression of c-myc or c-Ki-ras oncogenes in human cervical carcinoma cells

International Nuclear Information System (INIS)

Osmak, M.; Soric, J.; Matulic, M.

1993-01-01

Multiple fractions of gamma rays (0.5 Gy daily, 30 fractions) had previously been found to change the sensitivity of human cervical carcinoma HeLa cells to anticancer drugs. Preirradiated cells became resistant to cisplatin, methotrexate and vincristine but retained the same sensitivity to gamma rays and ultraviolet light. Some mechanisms involved in the resistance of preirradiated cells to cisplatin and vincristine were determined, i.e. the increased levels of metallothioneins and increased expression of plasma membrane P glycoprotein. As recent reports indicated that the resistance to cisplatin and ionizing radiation may involve the expression of oncogenes, the problem was studied whether multiple fractions of gamma rays can change the expression of c-myc and c-Ki-ras oncogenes in HeLa cells and whether there is a correlation between the expression of these oncogenes and the sensitivity of preirradiated cells to cisplatin and gamma rays. The expression of c-myc and c-Ki-ras oncogenes was examined using the DNA dot blot, the RNA dot blot and Northern blot analysis. The results show that preirradiation induced neither amplification nor elevated expression of c-myc and c-Ki-ras oncogenes. Furthermore, there is no correlation between the expression of c-myc and c-Ki-ras oncogenes and the acquired resistance to cisplatin. (author) 3 figs., 32 refs

Oncogenic LINE-1 Retroelements Sustain Prostate Tumor Cells and Promote Metastatic Progression

Science.gov (United States)

2015-10-01

limit to 20 words ). 3. ACCOMPLISHMENTS: The PI is reminded that the recipient organization is required to obtain prior written approval...activating novel oncogenic transcriptional pathways and by acting as a telomerase thereby contributing to immortalization of the metastases. We also

Imaging manifestations and its clinical significance in patients with oncogenic osteomalacia

International Nuclear Information System (INIS)

Yu Wei; Lin Qiang; Zhang Yunqing; Jiang Bo; Jin Jin; Jiang Yan; Li Mei; Li Fang

2006-01-01

Objective: To compare images from different modality for detecting lesions in patients with oncogenic osteomalacia. Methods: Eight patients with oncogenic osteomalacia were recruited in this study. The age ranged from 28 to 69 years (mean age 44.1, 5 men and 3 women). All patients were diagnosed as osteomalacia according to their clinical and radiographic manifestations. Main laboratory tests included serum calcium, phosphorus, alkaline phosphatase activity, parathyroid hormone, urinary phosphorus as well as liver and renal functions. Octreotide scans were performed for all patients according to clinical request for confirming the oncogenic osteomalacia. Further examinations of MR imaging in 8 patients, spiral CT in four patients and conventional radiography in four patients were obtained after the octreotide scans respectively. All patients had operation for their tumor resections and for the pathologic diagnostic findings. Results: Abnormal laboratory findings in all patients included low serum phosphorus level (ranged from 0.29 to 0.65 mmol·L -1 ), elevated alkaline phosphatase activity (ranged from 36. 6 to 310.6 μmol·s -1 ·L -1 ) as well as urinary phosphorus level (ranged from 11.5 to 40. 9 mmol·L -1 ). Normal results included parathyroid hormone level, liver and renal functions. Pathology confirmed the diagnosis of 4 soft tissue tumors including 1 hemangiomas, 1 giant-cell tumor of tendon sheath, 1 hemangiopericytoma and 1 mesenchymal tumor, as well as 4 bone tumors including 1 malignant neurofibroma, 2 mesenchymal tumors and 1 fibroblastoma. All lesions were shown abnormal region of increasing uptake tracer on octreotide scans. However, the octreotide scans could not determine where (bone or soft tissues) the lesions located. MR imaging could differentiate the lesions within the bone or within the soft tissues in all patients. All lesions had hypo- or iso- signal intensity on T 1 WI and high signal intensity on T 2 WI with heterogeneous in 6 tumors and

A germline RET proto-oncogene mutation in multiple members of an ...

African Journals Online (AJOL)

Background: Multiple endocrine neoplasia type 2A (MEN2A) is a rare cancer associated-syndrome, inherited in an autosomal dominant fashion and caused by germline mutation in RET proto-oncogene. Clinical diagnosis depends on the manifestation of two or more certain endocrine tumors in an individual, such as ...

MSH3-deficiency initiates EMAST without oncogenic transformation of human colon epithelial cells.

Directory of Open Access Journals (Sweden)

Christoph Campregher

Full Text Available BACKGROUND/AIM: Elevated microsatellite instability at selected tetranucleotide repeats (EMAST is a genetic signature in certain cases of sporadic colorectal cancer and has been linked to MSH3-deficiency. It is currently controversial whether EMAST is associated with oncogenic properties in humans, specifically as cancer development in Msh3-deficient mice is not enhanced. However, a mutator phenotype is different between species as the genetic positions of repetitive sequences are not conserved. Here we studied the molecular effects of human MSH3-deficiency. METHODS: HCT116 and HCT116+chr3 (both MSH3-deficient and primary human colon epithelial cells (HCEC, MSH3-wildtype were stably transfected with an EGFP-based reporter plasmid for the detection of frameshift mutations within an [AAAG]17 repeat. MSH3 was silenced by shRNA and changes in protein expression were analyzed by shotgun proteomics. Colony forming assay was used to determine oncogenic transformation and double strand breaks (DSBs were assessed by Comet assay. RESULTS: Despite differential MLH1 expression, both HCT116 and HCT116+chr3 cells displayed comparable high mutation rates (about 4×10(-4 at [AAAG]17 repeats. Silencing of MSH3 in HCECs leads to a remarkable increased frameshift mutations in [AAAG]17 repeats whereas [CA]13 repeats were less affected. Upon MSH3-silencing, significant changes in the expression of 202 proteins were detected. Pathway analysis revealed overexpression of proteins involved in double strand break repair (MRE11 and RAD50, apoptosis, L1 recycling, and repression of proteins involved in metabolism, tRNA aminoacylation, and gene expression. MSH3-silencing did not induce oncogenic transformation and DSBs increased 2-fold. CONCLUSIONS: MSH3-deficiency in human colon epithelial cells results in EMAST, formation of DSBs and significant changes of the proteome but lacks oncogenic transformation. Thus, MSH3-deficiency alone is unlikely to drive human colon

The role of hypoxia inducible factor-1 alpha in bypassing oncogene-induced senescence.

Directory of Open Access Journals (Sweden)

Mehtap Kilic Eren

Full Text Available Oncogene induced senescence (OIS is a sustained anti-proliferative response acutely induced in primary cells via activation of mitogenic oncogenes such as Ras/BRAF. This mechanism acts as an initial barrier preventing normal cells transformation into malignant cell. Besides oncogenic activation and DNA damage response (DDR, senescence is modulated by a plethora of other factors, and one of the most important one is oxygen tension of the tissue. The aim of this study was to determine the impact of hypoxia on RasV12-induced senescence in human diploid fibroblasts (HDFs. We showed here that hypoxia prevents execution of oncogene induced senescence (OIS, through a strong down-regulation of senescence hallmarks, such as SA- β-galactosidase, H3K9me3, HP1γ, p53, p21CIP1 and p16INK4a in association with induction of hypoxia inducible factor-1α (HIF-1α. In addition, hypoxia also decreased marks of H-RasV12-induced DDR in both cell lines through down-regulation of ATM/ATR, Chk1 and Chk2 phosphorylation as well as decreased γ-H2AX positivity. Utilizing shRNA system targeting HIF-1α we show that HIF-1α is directly involved in down regulation of p53 and its target p21CIP1 but not p16INK4a. In line with this finding we found that knock down of HIF-1α leads to a strong induction of apoptotic response, but not restoration of senescence in Ras expressing HDFs in hypoxia. This indicates that HIF-1α is an important player in early steps of tumorigenesis, leading to suppression of senescence through its negative regulation of p53 and p21CIP1. In our work we describe a mechanism through which hypoxia and specifically HIF-1α preclude cells from maintaining senescence-driven anti proliferative response. These findings indicate the possible mechanism through which hypoxic environment helps premalignant cells to evade impingement of cellular failsafe pathways.

Carcinogenic viruses in etiopathogenesis of skin cancers in patients after organ transplantation

Directory of Open Access Journals (Sweden)

Maria Luiza Piesiaków

2016-02-01

Full Text Available The latest literature report specifies multifactoral etiology of skin cancer in population of patients after organs transplats. Carcirogenic viruses are one of etiopathogenesis components. Viruses of a vital meaning for skin oncogenesis are called Human papillomavirus – HPV, Human herpesvirus 8 – HHV8 i Merkel cell polyomavirus – MCV. Report on connections exisisting between viruses HPV and skin cancers in the population of patients after organs transplants confirms clinical connection between viruses papillas and cancers centres occuring in similar locations and more frequent appearance of attributes characteristic for HPV infection within the limits of changes in the type of Squamous cell carcinoma (SCC. What’s more, coexisting of viruses papillas and SCC is more often noticed in the population of organ recipients than in the population of healthy people. It is not confirmed yet that any specific correlation between subtypes of HPV and greater frequency of morbidity in skin cancers really exist. However, in the population of organ recipients infections of different types of HPV are found within the limits of cancers centres in the case of SCC (63% as well as in basal cell carcinoma-BCC (55%. DNA of HPV was also fund in healthy parts of organ recipients skin (92-94%.HHV8 is also an oncogenic viruse that influences the development of lymphoma. Infection of that virus may cause ocuuring of Kaposi’s sarkoma, which is one of the most frequent types of cancer appearing in population of patients treating by long – term immunosuppression in particular geographical zones. MCV, which belongs to the group called Polyomaviriade, owes a particular meaning in etiopathogenesis of Merkel cell carcinoma – MCC. It is a rare cancer derived from neuroendocrine cells of the basic layers of epidermie. For over 30 years it was supposed that correlation between viruses and skin cancers in population of organ recipient exist. Knowledge of the total

Carcinogenic viruses in etiopathogenesis of skin cancers in patients after organ transplantation

Directory of Open Access Journals (Sweden)

Maria Luiza Piesiaków

2016-02-01

Full Text Available The latest literature report specifies multifactoral etiology of skin cancer in population of patients after organs transplats. Carcirogenic viruses are one of etiopathogenesis components. Viruses of a vital meaning for skin oncogenesis are called Human papillomavirus – HPV, Human herpesvirus 8 – HHV8 i Merkel cell polyomavirus – MCV. Report on connections exisisting between viruses HPV and skin cancers in the population of patients after organs transplants confirms clinical connection between viruses papillas and cancers centres occuring in similar locations and more frequent appearance of attributes characteristic for HPV infection within the limits of changes in the type of Squamous cell carcinoma (SCC. What’s more, coexisting of viruses papillas and SCC is more often noticed in the population of organ recipients than in the population of healthy people. It is not confirmed yet that any specific correlation between subtypes of HPV and greater frequency of morbidity in skin cancers really exist. However, in the population of organ recipients infections of different types of HPV are found within the limits of cancers centres in the case of SCC (63% as well as in basal cell carcinoma-BCC (55%. DNA of HPV was also fund in healthy parts of organ recipients skin (92-94%. HHV8 is also an oncogenic viruse that influences the development of lymphoma. Infection of that virus may cause ocuuring of Kaposi’s sarkoma, which is one of the most frequent types of cancer appearing in population of patients treating by long – term immunosuppression in particular geographical zones. MCV, which belongs to the group called Polyomaviriade, owes a particular meaning in etiopathogenesis of Merkel cell carcinoma – MCC. It is a rare cancer derived from neuroendocrine cells of the basic layers of epidermie. For over 30 years it was supposed that correlation between viruses and skin cancers in population of organ recipient exist. Knowledge of the total

The Homeodomain Transcription Factor Cdx1 Does Not Behave as an Oncogene in Normal Mouse Intestine1

Science.gov (United States)

Crissey, Mary Ann S; Guo, Rong-Jun; Fogt, Franz; Li, Hong; Katz, Jonathan P; Silberg, Debra G; Suh, Eun Ran; Lynch, John P

2008-01-01

The Caudal-related homeobox genes Cdx1 and Cdx2 are intestine-specific transcription factors that regulate differentiation of intestinal cell types. Previously, we have shown Cdx1 to be antiproliferative and to promote cell differentiation. However, other studies have suggested that Cdx1 may be an oncogene. To test for oncogenic behavior, we used the murine villin promoter to ectopically express Cdx1 in the small intestinal villi and colonic surface epithelium. No changes in intestinal architecture, cell differentiation, or lineage selection were observed with expression of the transgene. Classic oncogenes enhance proliferation and induce tumors when ectopically expressed. However, the Cdx1 transgene neither altered intestinal proliferation nor induced spontaneous intestinal tumors. In a murine model for colitis-associated cancer, the Cdx1 transgene decreased, rather than increased, the number of adenomas that developed. In the polyps, the expression of the endogenous and the transgenic Cdx1 proteins was largely absent, whereas endogenous Villin expression was retained. This suggests that transgene silencing was specific and not due to a general Villin inactivation. In conclusion, neither the ectopic expression of Cdx1 was associated with changes in intestinal cell proliferation or differentiation nor was there increased intestinal cancer susceptibility. Our results therefore suggest that Cdx1 is not an oncogene in normal intestinal epithelium. PMID:18231635

Primary structure of the human fgr proto-oncogene product p55/sup c-fgr/

Energy Technology Data Exchange (ETDEWEB)

Katamine, S.; Notario, V.; Rao, C.D.; Miki, T.; Cheah, M.S.C.; Tronick, S.R.; Robbins, K.C.

1988-01-01

Normal human c-fgr cDNA clones were constructed by using normal peripheral blood mononuclear cell mRNA as a template. Nucleotide sequence analysis of two such clones revealed a 1,587-base-pair-long open reading frame which predicted the primary amino acid sequence of the c-fgr translational product. Homology of this protein with the v-fgr translational product stretched from codons 128 to 516, where 32 differences among 388 codons were observed. Sequence similarity with human c-src, c-yes, and fyn translations products began at amino acid position 76 of the predicted c-fgr protein and extended nearly to its C-terminus. In contrast, the stretch of 75 amino acids at the N-terminus demonstrated a greatly reduced degree of relatedness to these same proteins. To verify the deduced amino acid sequence, antibodies were prepared against peptides representing amino- and carboxy-terminal regions of the predicted c-fgr translational product. Both antibodies specifically recognized a 55-kilodalton protein expressed in COS-1 cells transfected with a c-fgr cDNA expression plasmid. Moreover, the same protein was immunoprecipitated from an Epstein-Barr virus-infected Burkitt's lymphoma cell line which expressed c-fgr mRNA but not in its uninfected fgr mRNA-negative counterpart. These findings identified the 55-kilodalton protein as the product of the human fgr proto-oncogene.

ERBB oncogene proteins as targets for monoclonal antibodies.

Science.gov (United States)

Polanovski, O L; Lebedenko, E N; Deyev, S M

2012-03-01

General properties of the family of tyrosine kinase ERBB receptors are considered in connection with their role in the generation of cascades of signal transduction in normal and tumor cells. Causes of acquisition of oncogene features by genes encoding these receptors and their role in tumorigenesis are analyzed. Anti-ERBB monoclonal antibodies approved for therapy are described in detail, and mechanisms of their antitumor activity and development of resistance to them are reviewed. The existing and the most promising strategies for creating and using monoclonal antibodies and their derivatives for therapy of cancer are discussed.

Undifferentiated Pleomorphic Sarcoma and the Importance of Considering the Oncogenic and Immune-Suppressant Role of the Human T-Cell Lymphotropic Virus Type 1: A Case Report

Directory of Open Access Journals (Sweden)

Sergio Lupo

2017-05-01

Full Text Available IntroductionSoft-tissue sarcomas account for 0.7% of all malignant tumors, with an incidence rate of 3 per 100,000 persons/year. The undifferentiated pleomorphic sarcoma (UPS with giant cells, a high grade tumor of soft tissue, is very unusual, especially in young adults before the age of 40. Human T-cell lymphotropic virus type 1 (HTLV-1 is a human retrovirus, classified as group 1 human carcinogens by The International Agency for Research on Cancer, that causes an aggressive malignancy known as adult T-cell lymphoma/leukemia and a progressive chronic inflammatory neurological disease named HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP. HTLV-1 causes accumulation of genetic mutations in the host genome that could contribute to cellular transformation, one of the oncogenic features of HTLV-1.Case reportWe describe a case of a young woman with UPS who suffered from HAM/TSP with 3 years of evolution. In 2013, the patient started with neurological symptoms: weakness in the legs and bladder dysfunction. One year later, the patient developed a mild paraparesis in both extremities, anti-HTLV-1 antibodies were detected in plasma and in cerebrospinal fluid, and HAM/TSP was confirmed. In November 2015, a benign ganglion cyst was first suspected without intervention and by March 2016 a sarcoma was diagnosed. Three weeks after surgical resection, the tumor aroused in deep tissue and behaved aggressively, implicating a curative wide resection of the fibula, joint reconstruction, and soft-tissue graft. Histopathological examination confirmed UPS with giant cells.Concluding remarksThe unapparent subclinical immunodeficiency state due to HTLV-1 infection deserves to be considered in order to carefully monitor the possibility of developing any type of cancer. Besides, reaching an accurate and timely diagnosis of UPS can be challenging due to the difficulty in diagnosis/classification and delayed consultation. In this particular case

Role of 18F FDG PET scan to localize tumor in patients of oncogenic osteomalacia

International Nuclear Information System (INIS)

Malhotra, Gaurav; Mukta, K.; Asopa, V.; Varsha, J.; Vijaya, S.; Shah, Nalini S.; Padmavathy, M.

2010-01-01

Full text: Oncogenic osteomalacia is a rare paraneoplastic syndrome of renal phosphate wasting which is usually caused by phosphaturic mesenchymal tumors. Conventional radiologic techniques usually fail to detect these small, slow growing neoplasms located at unusual sites. The objective of this study was to evaluate the role of 18 F FDG PET imaging in patients of oncogenic osteomalacia. Materials and Methods: Fifteen patients (8 males and 7 females) (mean age: 38.5 ± 12.2 years) with clinical and biochemical evidence of oncogenic osteomalacia were subjected to 'total' whole body 18 F FDG PET scan including both limbs and skull views. The images were reconstructed and the final output was displayed as per the standard institution protocol. Results: 18 F FDG PET imaging localized suspicious hypermetabolic foci of SUVmax ranging from 1.4 to 3.8 (Mean ± S.D.: 2.39 ± 0.63) suggesting presence of occult tumor in 11 of 15 patients. The suspected foci were localized in lower limbs in ten patients and in the petrous temporal region of skull in 1 patient. FDG localized tumors were histopathologically correlated in 6 patients who underwent surgical biopsy/excision after correlative radiological investigations. Four of these patients were cured after surgical excision while partial surgical excision/biopsy was performed in two patients. Conclusions: 18 F FDG PET imaging is a promising technique for detection of occult tumors in patients of oncogenic osteomalacia. It is mandatory to include limbs in the field as these tumors are common in limbs and may be easily missed. Preoperative localization increases odds for cure after surgical removal of tumor

Infection with the oncogenic human papillomavirus type 59 alters protein components of the cornified cell envelope

International Nuclear Information System (INIS)

Lehr, Elizabeth; Brown, Darron R.

2003-01-01

Infection of the genital tract with human papillomaviruses (HPVs) leads to proliferative and dysplastic epithelial lesions. The mechanisms used by the virus to escape the infected keratinocyte are not well understood. Infection of keratinocytes with HPV does not cause lysis, the mechanism used by many viruses to release newly formed virions. For HPV 11, a type associated with a low risk of neoplastic disease, the cornified cell envelope (CCE) of infected keratinocytes is thin and fragile, and transcription of loricrin, the major CCE protein, is reduced. The effects of high-risk HPV infection on components of the CCE have not been previously reported. HPV 59, an oncogenic genital type related to HPV types 18 and 45 was identified in a condylomata acuminata lesion. An extract of this lesion was used to infect human foreskin fragments, which were grown in athymic mice as xenografts. Continued propagation using extracts of xenografts permitted growth of additional HPV 59-infected xenografts. CCEs purified from HPV 59-infected xenografts displayed subtle morphologic abnormalities compared to those derived from uninfected xenografts. HPV 59-infected xenografts revealed dysplastic-appearing cells with mitotic figures. Detection of loricrin, involucrin, and cytokeratin 10 was reduced in HPV 59-infected epithelium, while small proline-rich protein 3 (SPR3) was increased. Reduction in loricrin was most apparent in regions of epithelium containing abundant HPV 59 DNA. Compared to uninfected epithelium, loricrin transcription was decreased in HPV 59-infected epithelium. We conclude that HPV 59 shares with HPV 11 the ability to alter CCE components and to specifically reduce transcription of the loricrin gene. Because loricrin is the major CCE protein, a reduction in this component could alter the physical properties of the CCE, thus facilitating virion release

Localisation of lung cancer by a radiolabelled monoclonal antibody against the c-myc oncogene product

Energy Technology Data Exchange (ETDEWEB)

Chan, S Y.T.; Evan, G I; Ritson, A; Watson, J; Wraight, P; Sikora, K

1986-11-01

A set of mouse monoclonal antibodies against the c-myc oncogene product, a 62,000 dalton nuclear binding protein involved in cell cycle control, has been constructed by immunisation with synthetic peptide fragments. One such antibody, CT14, was radiolabelled with /sup 131/I and administered to 20 patients with different malignant diseases. Good tumour localisation was observed in 12 out of 14 patients with primary bronchial carcinoma but not in patients with pulmonary metastases from primary tumours elsewhere. Successfully localised tumours were all 3 cm or more in diameter. Monoclonal antibodies against oncogene products may provide novel selective tools for the diagnosis and therapy of cancer.

Expression of proto-oncogenes in non-Hodgkin's lymphomas by in situ hybridization with biotinylated DNA probes

International Nuclear Information System (INIS)

Hamatani, Kiyohiro; Yoshida, Kuniko; Abe, Masumi; Shimaoka, Katsutaro; Shiku, Hiroshi; Akiyama, Mitoshi; Kondo, Hisayoshi.

1989-11-01

Expression of six proto-oncogenes (fos, myc, myb, Ki-ras, Ha-ras, and N-ras) in 43 cases of non-Hodgkin's lymphoma was analyzed by means of in situ hybridization. Biotinylated DNA probes of the six oncogenes and those of the immunoglobulin H-chain (IgH) gene and the T cell receptor β-chain (TCRβ) gene were used. The results of in situ hybridization performed under blind conditions by IgH and TCRβ gene probes were compatible with those of typing by cell surface markers. The nuclear protein-related proto-oncogenes, fos myc, and myb, were expressed in about 70 % - 80 % of all cases regardless of phenotypes, histology or histologic grade. On the contrary, genes of the ras family were expressed in fewer cases except for the Ki-ras gene which was more frequently expressed by cases of the T cell immunophenotype with a high malignancy grade. The results of dot hybridization with RNA extracted from some cases were compatible with those of in situ hybridization, further demonstrating the specificity of in situ hybridization. (author)

Epstein-Barr virus associated modulation of Wnt pathway is not dependent on latent membrane protein-1.

Directory of Open Access Journals (Sweden)

Natasha Webb

2008-09-01

Full Text Available Previous studies have indicated that Epstein-Barr virus (EBV can modulate the Wnt pathway in virus-infected cells and this effect is mediated by EBV-encoded oncogene latent membrane protein 1 (LMP1. Here we have reassessed the role of LMP1 in regulating the expression of various mediators of the canonical Wnt cascade. Contradicting the previous finding, we found that the levels of E-cadherin, beta-catenin, Glycogen Synthase Kinase 3ss (GSK3beta, axin and alpha-catenin were not affected by the expression of LMP1 sequences from normal B cells or nasopharyngeal carcinoma. Moreover, we also show that LMP1 expression had no detectable effect on the E-cadherin and beta-catenin interaction and did not induce transcriptional activation of beta-catenin. Taken together these studies demonstrate that EBV-mediated activation of Wnt pathway is not dependent on the expression of LMP1.

Molecular Detection of Epstein - Barr virus in Nasopharyngeal Carcinoma among Sudanese population

Directory of Open Access Journals (Sweden)

Ali Edris

2016-11-01

Full Text Available Abstract Background Nasopharyngeal carcinoma (NPC is the most common cancer arising from the nasopharynx that varies significantly from other cancers of the head and neck in its occurrence, causes, clinical behavior, and treatment. NPC caused by an interaction between infection with EBV and environmental and genetic factors, encompasses a multistep oncogenic process. The frequency of Epstein-Barr virus EBV among nasopharyngeal carcinoma is well known worldwide, however, in the Sudan there is barely a published data. The aim of this study was to detect Epstein-Barr virus (EBV in nasopharyngeal carcinoma (NPC biopsies obtained from Sudanese patients using Polymerase Chain reaction. Methods This is a descriptive, retrospective hospital based study, conducted at the National Center for ENT diseases and the Faculty of Medical Laboratory Science, University of Khartoum, Khartoum City, Sudan. Archival blocks were obtained from 82 patients diagnosed as having nasopharyngeal carcinoma were molecularly examined for the presence of Epstein-Barr virus. Results Eighty two Paraffin fixed tissue sections were examined for the presence of the virus using PCR, EBV was identified in 51/ 82 (62.2% samples and couldn’t be identified in 31/ 82 (37.8% tissue samples. Out of the 51 infected samples, 33/51 (64.7% were found among males and 18/27 (66.7% were found among females. Conclusion The present study is providing strong evidence supporting the general association of EBV infection in NPC among Sudanese patients.

Skin carcinomas in organ-transplant recipients : from early oncogenic events to therapy

NARCIS (Netherlands)

Graaf, Ymke Grete Leontien de

2008-01-01

Skin carcinomas develop at a high rate in organ-transplant recipients who are kept on immune suppressive drugs to prevent graft rejection. The present study dealt with a broad range of aspects of this elevated carcinoma risk, starting from the earliest oncogenic events to the ultimate therapy.

TAD disruption as oncogenic driver.

Science.gov (United States)

Valton, Anne-Laure; Dekker, Job

2016-02-01

Topologically Associating Domains (TADs) are conserved during evolution and play roles in guiding and constraining long-range regulation of gene expression. Disruption of TAD boundaries results in aberrant gene expression by exposing genes to inappropriate regulatory elements. Recent studies have shown that TAD disruption is often found in cancer cells and contributes to oncogenesis through two mechanisms. One mechanism locally disrupts domains by deleting or mutating a TAD boundary leading to fusion of the two adjacent TADs. The other mechanism involves genomic rearrangements that break up TADs and creates new ones without directly affecting TAD boundaries. Understanding the mechanisms by which TADs form and control long-range chromatin interactions will therefore not only provide insights into the mechanism of gene regulation in general, but will also reveal how genomic rearrangements and mutations in cancer genomes can lead to misregulation of oncogenes and tumor suppressors. Copyright © 2016 Elsevier Ltd. All rights reserved.

Menin-MLL inhibitors reverse oncogenic activity of MLL fusion proteins in leukemia.

Science.gov (United States)

Grembecka, Jolanta; He, Shihan; Shi, Aibin; Purohit, Trupta; Muntean, Andrew G; Sorenson, Roderick J; Showalter, Hollis D; Murai, Marcelo J; Belcher, Amalia M; Hartley, Thomas; Hess, Jay L; Cierpicki, Tomasz

2012-01-29

Translocations involving the mixed lineage leukemia (MLL) gene result in human acute leukemias with very poor prognosis. The leukemogenic activity of MLL fusion proteins is critically dependent on their direct interaction with menin, a product of the multiple endocrine neoplasia (MEN1) gene. Here we present what are to our knowledge the first small-molecule inhibitors of the menin-MLL fusion protein interaction that specifically bind menin with nanomolar affinities. These compounds effectively reverse MLL fusion protein-mediated leukemic transformation by downregulating the expression of target genes required for MLL fusion protein oncogenic activity. They also selectively block proliferation and induce both apoptosis and differentiation of leukemia cells harboring MLL translocations. Identification of these compounds provides a new tool for better understanding MLL-mediated leukemogenesis and represents a new approach for studying the role of menin as an oncogenic cofactor of MLL fusion proteins. Our findings also highlight a new therapeutic strategy for aggressive leukemias with MLL rearrangements.

Fusion peptides from oncogenic chimeric proteins as putative specific biomarkers of cancer.

Science.gov (United States)

Conlon, Kevin P; Basrur, Venkatesha; Rolland, Delphine; Wolfe, Thomas; Nesvizhskii, Alexey I; MacCoss, Michael J; Lim, Megan S; Elenitoba-Johnson, Kojo S J

2013-10-01

Chromosomal translocations encoding chimeric fusion proteins constitute one of the most common mechanisms underlying oncogenic transformation in human cancer. Fusion peptides resulting from such oncogenic chimeric fusions, though unique to specific cancer subtypes, are unexplored as cancer biomarkers. Here we show, using an approach termed fusion peptide multiple reaction monitoring mass spectrometry, the direct identification of different cancer-specific fusion peptides arising from protein chimeras that are generated from the juxtaposition of heterologous genes fused by recurrent chromosomal translocations. Using fusion peptide multiple reaction monitoring mass spectrometry in a clinically relevant scenario, we demonstrate the specific, sensitive, and unambiguous detection of a specific diagnostic fusion peptide in clinical samples of anaplastic large cell lymphoma, but not in a diverse array of benign lymph nodes or other forms of primary malignant lymphomas and cancer-derived cell lines. Our studies highlight the utility of fusion peptides as cancer biomarkers and carry broad implications for the use of protein biomarkers in cancer detection and monitoring.

Oncogenes and tumor suppressors in the molecular pathogenesis of acute promyelocytic leukemia.

Science.gov (United States)

Pandolfi, P P

2001-04-01

Acute promyelocytic leukemia (APL) is associated with reciprocal chromosomal translocations always involving the retinoic acid receptor alpha (RARalpha) gene on chromosome 17 and variable partner genes (X genes) on distinct chromosomes. RARalpha fuses to the PML gene in the vast majority of APL cases, and in a few cases to the PLZF, NPM, NuMA and Stat5b genes, respectively, leading to the generation of RARalpha-X: and X:-RARalpha fusion genes. Both fusion proteins can exert oncogenic functions through their ability to interfere with the activities of X and RARalpha proteins. Here, it will be discussed in detail how an extensive biochemical analysis as well as a systematic in vivo genetic approach in the mouse has allowed the definition of the multiple oncogenic activities of PML-RARalpha, and how it has become apparent that this oncoprotein is able to impair RARalpha at the transcription level and the tumor suppressive function of the PML protein.

Prime-boost therapeutic vaccination in mice with DNA/DNA or DNA/Fowlpox virus recombinants expressing the Human Papilloma Virus type 16 E6 and E7 mutated proteins fused to the coat protein of Potato virus X.

Science.gov (United States)

Illiano, Elena; Bissa, Massimiliano; Paolini, Francesca; Zanotto, Carlo; De Giuli Morghen, Carlo; Franconi, Rosella; Radaelli, Antonia; Venuti, Aldo

2016-10-02

The therapeutic antitumor potency of a prime-boost vaccination strategy was explored, based on the mutated, nontransforming forms of the E6 (E6 F47R ) and E7 (E7 GGG ) oncogenes of Human Papilloma Virus type 16 (HPV16), fused to the Potato virus X (PVX) coat protein (CP) sequence. Previous data showed that CP fusion improves the immunogenicity of tumor-associated antigens and may thus increase their efficacy. After verifying the correct expression of E6 F47R CP and E7 GGG CP inserted into DNA and Fowlpox virus recombinants by Western blotting and immunofluorescence, their combined use was evaluated for therapy in a pre-clinical mouse model of HPV16-related tumorigenicity. Immunization protocols were applied using homologous (DNA/DNA) or heterologous (DNA/Fowlpox) prime-boost vaccine regimens. The humoral immune responses were determined by ELISA, and the therapeutic efficacy evaluated by the delay in tumor appearance and reduced tumor volume after inoculation of syngeneic TC-1* tumor cells. Homologous DNA/DNA genetic vaccines were able to better delay tumor appearance and inhibit tumor growth when DNAE6 F47R CP and DNAE7 GGG CP were administered in combination. However, the heterologous DNA/Fowlpox vaccination strategy was able to delay tumor appearance in a higher number of animals when E6 F47R CP and in particular E7 GGG CP were administered alone. Copyright © 2016 Elsevier B.V. All rights reserved.

The oncogenic action of ionizing radiation on rat skin

International Nuclear Information System (INIS)

Burns, F.J.; Garte, S.J.

1990-01-01

An extensive experiment involving approximately 400 rats exposed to the neon ion beam at the Bevalac in Berkeley, CA and to electrons is nearing completion. Progress is described in three areas corresponding to the specific aims of the proposal: (1) carcinogenesis and DNA strand breaks in rat skin following exposure by the neon ions or electrons; (2) oncogene activation in radiation-induced rat skin cancers; (3) DNA strand breaks in the epidermis as a function of radiation penetration. 59 refs., 4 tabs

Senescence-Associated Secretory Phenotypes Reveal Cell-Nonautonomous Functions of Oncogenic RAS and the p53 Tumor Suppressor

Energy Technology Data Exchange (ETDEWEB)

Copp& #233; , Jean-Philippe; Patil, Christopher; Rodier, Francis; Sun, Yu; Munoz, Denise; Goldstein, Joshua; Nelson, Peter; Desprez, Pierre-Yves; Campisi, Judith

2008-10-24

Cellular senescence suppresses cancer by arresting cell proliferation, essentially permanently, in response to oncogenic stimuli, including genotoxic stress. We modified the use of antibody arrays to provide a quantitative assessment of factors secreted by senescent cells. We show that human cells induced to senesce by genotoxic stress secrete myriad factors associated with inflammation and malignancy. This senescence-associated secretory phenotype (SASP) developed slowly over several days and only after DNA damage of sufficient magnitude to induce senescence. Remarkably similar SASPs developed in normal fibroblasts, normal epithelial cells, and epithelial tumor cells after genotoxic stress in culture, and in epithelial tumor cells in vivo after treatment of prostate cancer patients with DNA-damaging chemotherapy. In cultured premalignant epithelial cells, SASPs induced an epithelial-mesenchyme transition and invasiveness, hallmarks of malignancy, by a paracrine mechanism that depended largely on the SASP factors interleukin (IL)-6 and IL-8. Strikingly, two manipulations markedly amplified, and accelerated development of, the SASPs: oncogenic RAS expression, which causes genotoxic stress and senescence in normal cells, and functional loss of the p53 tumor suppressor protein. Both loss of p53 and gain of oncogenic RAS also exacerbated the promalignant paracrine activities of the SASPs. Our findings define a central feature of genotoxic stress-induced senescence. Moreover, they suggest a cell-nonautonomous mechanism by which p53 can restrain, and oncogenic RAS can promote, the development of age-related cancer by altering the tissue microenvironment.

Deciphering hepatocellular responses to metabolic and oncogenic stress

Directory of Open Access Journals (Sweden)

Kathrina L. Marcelo

2015-08-01

Full Text Available Each cell type responds uniquely to stress and fractionally contributes to global and tissue-specific stress responses. Hepatocytes, liver macrophages (MΦ, and sinusoidal endothelial cells (SEC play functionally important and interdependent roles in adaptive processes such as obesity and tumor growth. Although these cell types demonstrate significant phenotypic and functional heterogeneity, their distinctions enabling disease-specific responses remain understudied. We developed a strategy for the simultaneous isolation and quantification of these liver cell types based on antigenic cell surface marker expression. To demonstrate the utility and applicability of this technique, we quantified liver cell-specific responses to high-fat diet (HFD or diethylnitrosamine (DEN, a liver-specific carcinogen, and found that while there was only a marginal increase in hepatocyte number, MΦ and SEC populations were quantitatively increased. Global gene expression profiling of hepatocytes, MΦ and SEC identified characteristic gene signatures that define each cell type in their distinct physiological or pathological states. Integration of hepatic gene signatures with available human obesity and liver cancer microarray data provides further insight into the cell-specific responses to metabolic or oncogenic stress. Our data reveal unique gene expression patterns that serve as molecular “fingerprints” for the cell-centric responses to pathologic stimuli in the distinct microenvironment of the liver. The technical advance highlighted in this study provides an essential resource for assessing hepatic cell-specific contributions to metabolic and oncogenic stress, information that could unveil previously unappreciated molecular mechanisms for the cellular crosstalk that underlies the continuum from metabolic disruption to obesity and ultimately hepatic cancer.

Oncogenic transformation in C3H10T1/2 cells by low-energy neutrons.

Science.gov (United States)

Miller, R C; Marino, S A; Napoli, J; Shah, H; Hall, E J; Geard, C R; Brenner, D J

2000-03-01

Occupational exposure to neutrons typically includes significant doses of low-energy neutrons, with energies below 100 keV. In addition, the normal-tissue dose from boron neutron capture therapy will largely be from low-energy neutrons. Microdosimetric theory predicts decreasing biological effectiveness for neutrons with energies below about 350 keV compared with that for higher-energy neutrons; based on such considerations, and limited biological data, the current radiation weighting factor (quality factor) for neutrons with energies from 10 keV to 100 keV is less than that for higher-energy neutrons. By contrast, some reports have suggested that the biological effectiveness of low-energy neutrons is similar to that of fast neutrons. The purpose of the current work is to assess the relative biological effectiveness of low-energy neutrons for an endpoint of relevance to carcinogenesis: in vitro oncogenic transformation. Oncogenic transformation induction frequencies were determined for C3H10T1/2 cells exposed to two low-energy neutron beams, respectively, with dose-averaged energies of 40 and 70 keV, and the results were compared with those for higher-energy neutrons and X-rays. These results for oncogenic transformation provide evidence for a significant decrease in biological effectiveness for 40 keV neutrons compared with 350 keV neutrons. The 70 keV neutrons were intermediate in effectiveness between the 70 and 350 keV beams. A decrease in biological effectiveness for low-energy neutrons is in agreement with most (but not all) earlier biological studies, as well as microdosimetric considerations. The results for oncogenic transformation were consistent with the currently recommended decreased values for low-energy neutron radiation weighting factors compared with fast neutrons.

N-myc oncogene amplification is correlated to trace metal concentrations in neuroblastoma cultured cells

International Nuclear Information System (INIS)

Gouget, B.; Sergeant, C.; Benard, J.; Llabador, Y.; Simonoff, M.

2000-01-01

N-myc oncogene amplification is a powerful predictor of aggressive behavior of neuroblastoma (NB), the most common solid tumor of the early childhood. Since N-myc overexpression - subsequent to amplification - determines a phenotype of invasiveness and metastatic spreading, it is assumed that N-myc amplified neuroblasts synthesize zinc metalloenzymes leading to tumor invasion and formation of metastases. In order to test a possible relation between N-myc oncogene amplification and trace metal contents in human NB cells, Fe, Cu and Zn concentrations have been measured by nuclear microprobe analysis in three human neuroblastoma cell lines with various degrees of N-myc amplification. Elemental determinations show uniform distribution of trace metals within the cells, but variations of intracellular trace metal concentrations with respect to the degree of N-myc amplification are highly dependent on the nature of the element. Zinc concentration is higher in both N-myc amplified cell lines (IMR-32 and IGR-N-91) than in the non-amplified cells (SK-N-SH). In contrast, intracellular iron content is particularly low in N-myc amplified cell lines. Moreover, copper concentrations showed an increase with the degree of N-myc amplification. These results indicate that a relationship exists between intracellular trace metals and N-myc oncogene amplification. They further suggest that trace metals very probably play a determinant role in mechanisms of the neuroblastoma invasiveness

Differential splicing of oncogenes and tumor suppressor genes in African and Caucasian American populations: contributing factor in prostate cancer disparities

Science.gov (United States)

2017-12-01

populations: contributing factor in prostate cancer disparities? PRINCIPAL INVESTIGATOR: Norman H Lee, PhD CONTRACTING ORGANIZATION: George Washington...splicing of oncogenes and tumor suppressor genes in African and Caucasian American populations: contributing factor in prostate cancer disparities? 5b...American (AA) versus Caucasian American (CA) prostate cancer (PCa). We focused our efforts on two oncogenes, phosphatidylinositol-4,5-bisphosphate 3

Development of procedures for the identification of human papilloma virus DNA fragments in laser plume

Science.gov (United States)

Woellmer, Wolfgang; Meder, Tom; Jappe, Uta; Gross, Gerd; Riethdorf, Sabine; Riethdorf, Lutz; Kuhler-Obbarius, Christina; Loening, Thomas

1996-01-01

For the investigation of laser plume for the existence of HPV DNA fragments, which possibly occur during laser treatment of virus infected tissue, human papillomas and condylomas were treated in vitro with the CO2-laser. For the sampling of the laser plume a new method for the trapping of the material was developed by use of water-soluble gelatine filters. These samples were analyzed with the polymerase chain reaction (PCR) technique, which was optimized in regard of the gelatine filters and the specific primers. Positive PCR results for HPV DNA fragments up to the size of a complete oncogene were obtained and are discussed regarding infectiousity.

A Poly-ADP-Ribose Trigger Releases the Auto-Inhibition of a Chromatin Remodeling Oncogene

DEFF Research Database (Denmark)

Singh, Hari R; Nardozza, Aurelio P; Möller, Ingvar R

2017-01-01

DNA damage triggers chromatin remodeling by mechanisms that are poorly understood. The oncogene and chromatin remodeler ALC1/CHD1L massively decompacts chromatin in vivo yet is inactive prior to DNA-damage-mediated PARP1 induction. We show that the interaction of the ALC1 macrodomain......-macrodomain interactions, promotes an ungated conformation, and activates the remodeler's ATPase. ALC1 fragments lacking the regulatory macrodomain relax chromatin in vivo without requiring PARP1 activation. Further, the ATPase restricts the macrodomain's interaction with PARP1 under non-DNA damage conditions. Somatic...... cancer mutants disrupt ALC1's auto-inhibition and activate chromatin remodeling. Our data show that the NAD+-metabolite and nucleic acid PAR triggers ALC1 to drive chromatin relaxation. Modular allostery in this oncogene tightly controls its robust, DNA-damage-dependent activation....

Epstein-Barr virus infection and nasopharyngeal carcinoma.

Science.gov (United States)

Tsao, Sai Wah; Tsang, Chi Man; Lo, Kwok Wai

2017-10-19

Epstein-Barr virus (EBV) is associated with multiple types of human cancer, including lymphoid and epithelial cancers. The closest association with EBV infection is seen in undifferentiated nasopharyngeal carcinoma (NPC), which is endemic in the southern Chinese population. A strong association between NPC risk and the HLA locus at chromosome 6p has been identified, indicating a link between the presentation of EBV antigens to host immune cells and NPC risk. EBV infection in NPC is clonal in origin, strongly suggesting that NPC develops from the clonal expansion of a single EBV-infected cell. In epithelial cells, the default program of EBV infection is lytic replication. However, latent infection is the predominant mode of EBV infection in NPC. The establishment of latent EBV infection in pre-invasive nasopharyngeal epithelium is believed to be an early stage of NPC pathogenesis. Recent genomic study of NPC has identified multiple somatic mutations in the upstream negative regulators of NF-κB signalling. Dysregulated NF-κB signalling may contribute to the establishment of latent EBV infection in NPC. Stable EBV infection and the expression of latent EBV genes are postulated to drive the transformation of pre-invasive nasopharyngeal epithelial cells to cancer cells through multiple pathways.This article is part of the themed issue 'Human oncogenic viruses'. © 2017 The Author(s).

Transforming properties of Felis catus papillomavirus type 2 E6 and E7 putative oncogenes in vitro and their transcriptional activity in feline squamous cell carcinoma in vivo

Energy Technology Data Exchange (ETDEWEB)

Altamura, Gennaro, E-mail: gennaro.altamura@unina.it [Department of Veterinary Medicine and Animal Productions, General Pathology and Pathological Anatomy Unit, University of Naples Federico II, Via Delpino 1, 80137 Naples (Italy); Corteggio, Annunziata, E-mail: ancorteg@unina.it [Department of Veterinary Medicine and Animal Productions, General Pathology and Pathological Anatomy Unit, University of Naples Federico II, Via Delpino 1, 80137 Naples (Italy); Pacini, Laura, E-mail: PaciniL@students.iarc.fr [Infections and Cancer Biology Group, International Agency for Research on Cancer, 150 Cours Albert Thomas, 69372 Lyon (France); Conte, Andrea, E-mail: andreaconte88@hotmail.it [Department of Molecular Medicine and Medical Biotechnologies, University of Naples Federico II, Via Pansini 5, 80131 Naples (Italy); Pierantoni, Giovanna Maria, E-mail: gmpieran@unina.it [Department of Molecular Medicine and Medical Biotechnologies, University of Naples Federico II, Via Pansini 5, 80131 Naples (Italy); Tommasino, Massimo, E-mail: tommasinom@iarc.fr [Infections and Cancer Biology Group, International Agency for Research on Cancer, 150 Cours Albert Thomas, 69372 Lyon (France); Accardi, Rosita, E-mail: accardir@iarc.fr [Infections and Cancer Biology Group, International Agency for Research on Cancer, 150 Cours Albert Thomas, 69372 Lyon (France); Borzacchiello, Giuseppe, E-mail: borzacch@unina.it [Department of Veterinary Medicine and Animal Productions, General Pathology and Pathological Anatomy Unit, University of Naples Federico II, Via Delpino 1, 80137 Naples (Italy)

2016-09-15

Felis catus papillomavirus type 2 (FcaPV2) DNA is found in feline cutaneous squamous cell carcinomas (SCCs); however, its biological properties are still uncharacterized. In this study, we successfully expressed FcaPV2 E6 and E7 putative oncogenes in feline epithelial cells and demonstrated that FcaPV2 E6 binds to p53, impairing its protein level. In addition, E6 and E7 inhibited ultraviolet B (UVB)-triggered accumulation of p53, p21 and pro-apoptotic markers such as Cleaved Caspase3, Bax and Bak, suggesting a synergistic action of the virus with UV exposure in tumour pathogenesis. Furthermore, FcaPV2 E7 bound to feline pRb and impaired pRb levels, resulting in upregulation of the downstream pro-proliferative genes Cyclin A and Cdc2. Importantly, we demonstrated mRNA expression of FcaPV2 E2, E6 and E7 in feline SCC samples, strengthening the hypothesis of a causative role in the development of feline SCC. - Highlights: • FcaPV2 E6 binds to and deregulates feline p53 protein. • FcaPV2 E7 binds to and deregulates feline pRb protein. • FcaPV2 oncogenes inhibit UVB-induced apoptosis. • FcaPV2 E6E7 and E7 increase the lifespan of primary cells. • FcaPV2 E2, E6 and E7 are expressed at the mRNA level in feline SCC in vivo.

Malignancies and infection due to the human immunodeficiency virus. Are these emerging diseases?

Science.gov (United States)

Valencia Ortega, M E

2018-04-01

Since the start of the human immunodeficiency virus (HIV) epidemic, tumour disease among patients has been significant. The collection of malignancies can be divided primarily into 2 groups: those associated with HIV (all of which are related to viral diseases) and those not associated with HIV (only some of which are associated with viral diseases). The origin of these malignancies is multifactorial, and the main causes that have led to an increase in tumour disease are immunosuppression, coinfection with oncogenic viruses and life prolongation secondary to the use of antiretroviral therapy. Establishing the general characteristics of the undiagnosed AIDS tumours is difficult, mainly because they are a highly heterogeneous group formed by malignancies of a diverse nature. The treatments do not differ from those used in the general population, although the management can be more difficult due to the late diagnosis, drug interactions and associated comorbidities. Copyright © 2017 Elsevier España, S.L.U. and Sociedad Española de Medicina Interna (SEMI). All rights reserved.

Genomic Profiling on an Unselected Solid Tumor Population Reveals a Highly Mutated Wnt/β-Catenin Pathway Associated with Oncogenic EGFR Mutations

Directory of Open Access Journals (Sweden)

Jingrui Jiang

2018-04-01

Full Text Available Oncogenic epidermal growth factor receptors (EGFRs can recruit key effectors in diverse cellular processes to propagate oncogenic signals. Targeted and combinational therapeutic strategies have been successfully applied for treating EGFR-driven cancers. However, a main challenge in EGFR therapies is drug resistance due to mutations, oncogenic shift, alternative signaling, and other potential mechanisms. To further understand the genetic alterations associated with oncogenic EGFRs and to provide further insight into optimal and personalized therapeutic strategies, we applied a proprietary comprehensive next-generation sequencing (NGS-based assay of 435 genes to systematically study the genomic profiles of 1565 unselected solid cancer patient samples. We found that activating EGFR mutations were predominantly detected in lung cancer, particularly in non-small cell lung cancer (NSCLC. The mutational landscape of EGFR-driven tumors covered most key signaling pathways and biological processes. Strikingly, the Wnt/β-catenin pathway was highly mutated (48 variants detected in 46% of the EGFR-driven tumors, and its variant number topped that in the TP53/apoptosis and PI3K-AKT-mTOR pathways. Furthermore, an analysis of mutation distribution revealed a differential association pattern of gene mutations between EGFR exon 19del and EGFR L858R. Our results confirm the aggressive nature of the oncogenic EGFR-driven tumors and reassure that a combinational strategy should have advantages over an EGFR-targeted monotherapy and holds great promise for overcoming drug resistance.

Thrombopoietin/MPL participates in initiating and maintaining RUNX1-ETO acute myeloid leukemia via PI3K/AKT signaling

NARCIS (Netherlands)

J.A. Pulikkan (John); D. Madera (Dmitri); L. Xue (Liting); P. Bradley (Paul); S.F. Landrette (Sean Francis); Y.-H. Kuo (Ya-Huei); S. Abbas (Saman); L.J. Zhu (Lihua Julie); P.J.M. Valk (Peter); L.H. Castilla (Lucio)

2012-01-01

textabstractOncogenic mutations in components of cytokine signaling pathways elicit ligand-independent activation of downstream signaling, enhancing proliferation and survival in acute myeloid leukemia (AML). The myeloproliferative leukemia virus oncogene, MPL, a homodimeric receptor activated by

WSB1 overcomes oncogene-induced senescence by targeting ATM for degradation

Science.gov (United States)

Kim, Jung Jin; Lee, Seung Baek; Yi, Sang-Yeop; Han, Sang-Ah; Kim, Sun-Hyun; Lee, Jong-Min; Tong, Seo-Yun; Yin, Ping; Gao, Bowen; Zhang, Jun; Lou, Zhenkun

2017-01-01

Oncogene-induced senescence (OIS) or apoptosis through the DNA-damage response is an important barrier of tumorigenesis. Overcoming this barrier leads to abnormal cell proliferation, genomic instability, and cellular transformation, and finally allows cancers to develop. However, it remains unclear how the OIS barrier is overcome. Here, we show that the E3 ubiquitin ligase WD repeat and SOCS box-containing protein 1 (WSB1) plays a role in overcoming OIS. WSB1 expression in primary cells helps the bypass of OIS, leading to abnormal proliferation and cellular transformation. Mechanistically, WSB1 promotes ATM ubiquitination, resulting in ATM degradation and the escape from OIS. Furthermore, we identify CDKs as the upstream kinase of WSB1. CDK-mediated phosphorylation activates WSB1 by promoting its monomerization. In human cancer tissue and in vitro models, WSB1-induced ATM degradation is an early event during tumorigenic progression. We suggest that WSB1 is one of the key players of early oncogenic events through ATM degradation and destruction of the tumorigenesis barrier. Our work establishes an important mechanism of cancer development and progression in premalignant lesions. PMID:27958289

Analysis of the Epstein-Barr virus (EBV) latent membrane protein 1 (LMP-1) gene and promoter in Hodgkin's disease isolates

DEFF Research Database (Denmark)

Sandvej, K; Andresen, B S; Zhou, X G

2000-01-01

AIMS: To study the distribution of Epstein-Barr virus (EBV) variants containing mutations in the latent membrane protein 1 (LMP-1) oncogene and promoter in EBV associated Hodgkin's disease and infectious mononucleosis compared with previous findings in asymptomatic EBV carriers. METHODS: Sequence...... analysis of the EBV LMP-1 promoter and gene in isolates from Danish patients with Hodgkin's disease (n = 61) and infectious mononucleosis (n = 10). RESULTS: Viruses (previously designated group D) that contain two mutations in the activating transcription factor/cAMP response element (ATF/CRE) in the LMP-1...... promoter, which are known to decrease promoter activity greatly, were significantly less frequent in Hodgkin's disease than in both infectious mononucleosis (p = 0.0081) and asymptomatic EBV carriers (p = 0.0084). In some cases, the LMP-1 gene contained mutations in a recently identified cytotoxic T cell...

Characterization of ERAS, a putative novel human oncogene, in skin and breast

Energy Technology Data Exchange (ETDEWEB)

Peña Avalos, B.L. de la

2014-07-01

Most human tumors have mutations in genes of the RAS small GTPase protein family. RAS works as a molecular switch for signaling pathways that modulate many aspects of cell behavior, including proliferation, differentiation, motility and death. Oncogenic mutations in RAS prevent GTP hydrolysis, locking RAS in a permanently active state, being the most common mutations in HRAS, KRAS and NRAS. The human RAS family consists of at least 36 different genes, many of which have been scarcely studied. One of these relatively unknown genes is ERAS (ES cell-expressed RAS), which is a constitutively active RAS protein, localized in chromosome X and expressed only in embryonic cells, being undetectable in adult tissues. New high throughput technologies have made it possible to screen complete cancer genomes for identification of mutations associated to cancer. Using the Sleeping Beauty (SB) transposon system, ERAS was identified as a putative novel oncogene in non-melanoma skin and breast cancers. The major aim of this project is to determine the general characteristics of ERAS as a putative novel human oncogene in skin and breast cells. Forced expression of ERAS results in drastic changes in cell shape, proliferation and motility. When ERAS is overexpressed in skin and breast human cells it is mainly localized in the cytoplasmic membrane. ERAS activates the phosphatidylinositol-3-OH kinase (PI3K) pathway but not the mitogen-activated protein kinase (MAPK) pathway. ERAS-expressing cells suffer spontaneous morphologic and phenotypic EMT-like changes, including cytoskeleton reorganization, vimentin and N-cadherin up-regulation and down-regulation of E-cadherin, which can be associated with increased malignancy, and invasive and metastatic potential. Our results suggest that inappropriate expression of ERAS lead to transformation of human cells. (Author)

Simultaneous inhibition of multiple oncogenic miRNAs by a multi-potent microRNA sponge.

Science.gov (United States)

Jung, Jaeyun; Yeom, Chanjoo; Choi, Yeon-Sook; Kim, Sinae; Lee, EunJi; Park, Min Ji; Kang, Sang Wook; Kim, Sung Bae; Chang, Suhwan

2015-08-21

The roles of oncogenic miRNAs are widely recognized in many cancers. Inhibition of single miRNA using antagomiR can efficiently knock-down a specific miRNA. However, the effect is transient and often results in subtle phenotype, as there are other miRNAs contribute to tumorigenesis. Here we report a multi-potent miRNA sponge inhibiting multiple miRNAs simultaneously. As a model system, we targeted miR-21, miR-155 and miR-221/222, known as oncogenic miRNAs in multiple tumors including breast and pancreatic cancers. To achieve efficient knockdown, we generated perfect and bulged-matched miRNA binding sites (MBS) and introduced multiple copies of MBS, ranging from one to five, in the multi-potent miRNA sponge. Luciferase reporter assay showed the multi-potent miRNA sponge efficiently inhibited 4 miRNAs in breast and pancreatic cancer cells. Furthermore, a stable and inducible version of the multi-potent miRNA sponge cell line showed the miRNA sponge efficiently reduces the level of 4 target miRNAs and increase target protein level of these oncogenic miRNAs. Finally, we showed the miRNA sponge sensitize cells to cancer drug and attenuate cell migratory activity. Altogether, our study demonstrates the multi-potent miRNA sponge is a useful tool to examine the functional impact of simultaneous inhibition of multiple miRNAs and proposes a therapeutic potential.

Multiple-integrations of HPV16 genome and altered transcription of viral oncogenes and cellular genes are associated with the development of cervical cancer.

Directory of Open Access Journals (Sweden)

Xulian Lu

Full Text Available The constitutive expression of the high-risk HPV E6 and E7 viral oncogenes is the major cause of cervical cancer. To comprehensively explore the composition of HPV16 early transcripts and their genomic annotation, cervical squamous epithelial tissues from 40 HPV16-infected patients were collected for analysis of papillomavirus oncogene transcripts (APOT. We observed different transcription patterns of HPV16 oncogenes in progression of cervical lesions to cervical cancer and identified one novel transcript. Multiple-integration events in the tissues of cervical carcinoma (CxCa are significantly more often than those of low-grade squamous intraepithelial lesions (LSIL and high-grade squamous intraepithelial lesions (HSIL. Moreover, most cellular genes within or near these integration sites are cancer-associated genes. Taken together, this study suggests that the multiple-integrations of HPV genome during persistent viral infection, which thereby alters the expression patterns of viral oncogenes and integration-related cellular genes, play a crucial role in progression of cervical lesions to cervix cancer.

A 19-nucleotide insertion in the leader sequence of avian leukosis virus subgroup J contributes to its replication in vitro but is not related to its pathogenicity in vivo.

Directory of Open Access Journals (Sweden)

Xiaolin Ji

Full Text Available Subgroup J avian leukosis virus (ALV-J was first isolated from meat-type chickens that had developed myeloid leukosis and since 2008, ALV-J infections in chickens have become widespread in China. A comparison of the sequence of ALV-J epidemic isolates with HPRS-103, the ALV-J prototype virus, revealed several distinct features, one of which is a 19-nucleotide (nt insertion in the leader sequence. To determine the role of the 19-nt insertion in ALV-J pathogenicity, a pair of viruses were constructed and rescued. The first virus was an ALV-J Chinese isolate (designated rSD1009 containing the 19-nt insertion in its leader sequence. The second virus was a clone, in which the leader sequence had a deleted 19-nt sequence (designated rSD1009△19. Compared with rSD1009△19, rSD1009 displayed a moderate growth advantage in vitro. However, no differences were demonstrated in either viral replication or oncogenicity between the two rescued viruses in chickens. These results indicated that the 19-nt insertion contributed to ALV-J replication in vitro but was not related to its pathogenicity in vivo.

An oncogenic MYB feedback loop drives alternate cell fates in adenoid cystic carcinoma

Science.gov (United States)

Drier, Yotam; Cotton, Matthew J.; Williamson, Kaylyn E.; Gillespie, Shawn M.; Ryan, Russell J.H.; Kluk, Michael J.; Carey, Christopher D.; Rodig, Scott J.; Sholl, Lynette M; Afrogheh, Amir H.; Faquin, William C.; Queimado, Lurdes; Qi, Jun; Wick, Michael J.; El-Naggar, Adel K.; Bradner, James E.; Moskaluk, Christopher A.; Aster, Jon C.; Knoechel, Birgit; Bernstein, Bradley E.

2016-01-01

Translocation events are frequent in cancer and may create chimeric fusions or ‘regulatory rearrangements’ that drive oncogene overexpression. Here we identify super-enhancer translocations that drive overexpression of the oncogenic transcription factor MYB as a recurrent theme in adenoid cystic carcinoma (ACC). Whole-genome sequencing data and chromatin maps reveal distinct chromosomal rearrangements that juxtapose super-enhancers to the MYB locus. Chromosome conformation capture confirms that the translocated enhancers interact with the MYB promoter. Remarkably, MYB protein binds to the translocated enhancers, creating a positive feedback loop that sustains its expression. MYB also binds enhancers that drive different regulatory programs in alternate cell lineages in ACC, cooperating with TP63 in myoepithelial cells and a Notch program in luminal epithelial cells. Bromodomain inhibitors slow tumor growth in ACC primagraft models in vivo. Thus, our study identifies super-enhancer translocations that drive MYB expression and provides insight into downstream MYB functions in the alternate ACC lineages. PMID:26829750

GSK3 is required for rapalogs to induce degradation of some oncogenic proteins and to suppress cancer cell growth.

Science.gov (United States)

Koo, Junghui; Wang, Xuerong; Owonikoko, Taofeek K; Ramalingam, Suresh S; Khuri, Fadlo R; Sun, Shi-Yong

2015-04-20

The single-agent activity of rapalogs (rapamycin and its analogues) in most tumor types has been modest at best. The underlying mechanisms are largely unclear. In this report, we have uncovered a critical role of GSK3 in regulating degradation of some oncogenic proteins induced by rapalogs and cell sensitivity to rapalogs. The basal level of GSK3 activity was positively correlated with cell sensitivity of lung cancer cell lines to rapalogs. GSK3 inhibition antagonized rapamycin's growth inhibitory effects both in vitro and in vivo, while enforced activation of GSK3β sensitized cells to rapamycin. GSK3 inhibition rescued rapamcyin-induced reduction of several oncogenic proteins such as cyclin D1, Mcl-1 and c-Myc, without interfering with the ability of rapamycin to suppress mTORC1 signaling and cap binding. Interestingly, rapamycin induces proteasomal degradation of these oncogenic proteins, as evidenced by their decreased stabilities induced by rapamcyin and rescue of their reduction by proteasomal inhibition. Moreover, acute or short-time rapamycin treatment dissociated not only raptor, but also rictor from mTOR in several tested cell lines, suggesting inhibition of both mTORC1 and mTORC2. Thus, induction of GSK3-dependent degradation of these oncogenic proteins is likely secondary to mTORC2 inhibition; this effect should be critical for rapamycin to exert its anticancer activity.

The Expression, Purification, and Characterization of a Ras Oncogene (Bras2 in Silkworm (Bombyx mori

Directory of Open Access Journals (Sweden)

Zhengbing Lv

2013-01-01

Full Text Available The Ras oncogene of silkworm pupae (Bras2 may belong to the Ras superfamily. It shares 77% of its amino acid identity with teratocarcinoma oncogene 21 (TC21 related ras viral oncogene homolog-2 (R-Ras2 and possesses an identical core effector region. The mRNA of Bombyx mori Bras2 has 1412 bp. The open reading frame contains 603 bp, which encodes 200 amino acid residues. This recombinant BmBras2 protein was subsequently used as an antigen to raise a rabbit polyclonal antibody. Western blotting and real-time PCR analyses showed that BmBras2 was expressed during four developmental stages. The BmBras2 expression level was the highest in the pupae and was low in other life cycle stages. BmBras2 was expressed in all eight tested tissues, and it was highly expressed in the head, intestine, and epidermis. Subcellular localization studies indicated that BmBras2 was predominantly localized in the nuclei of Bm5 cells, although cytoplasmic staining was also observed to a lesser extent. A cell proliferation assay showed that rBmBras2 could stimulate the proliferation of hepatoma cells. The higher BmBras2 expression levels in the pupal stage, tissue expression patterns, and a cell proliferation assay indicated that BmBras2 promotes cell division and proliferation, most likely by influencing cell signal transduction.

The Expression, Purification, and Characterization of a Ras Oncogene (Bras2) in Silkworm (Bombyx mori).

Science.gov (United States)

Lv, Zhengbing; Wang, Tao; Zhuang, Wenhua; Wang, Dan; Chen, Jian; Nie, Zuoming; Liu, Lili; Zhang, Wenping; Wang, Lisha; Wang, Deming; Wu, Xiangfu; Li, Jun; Qian, Lian; Zhang, Yaozhou

2013-01-01

The Ras oncogene of silkworm pupae (Bras2) may belong to the Ras superfamily. It shares 77% of its amino acid identity with teratocarcinoma oncogene 21 (TC21) related ras viral oncogene homolog-2 (R-Ras2) and possesses an identical core effector region. The mRNA of Bombyx mori Bras2 has 1412 bp. The open reading frame contains 603 bp, which encodes 200 amino acid residues. This recombinant BmBras2 protein was subsequently used as an antigen to raise a rabbit polyclonal antibody. Western blotting and real-time PCR analyses showed that BmBras2 was expressed during four developmental stages. The BmBras2 expression level was the highest in the pupae and was low in other life cycle stages. BmBras2 was expressed in all eight tested tissues, and it was highly expressed in the head, intestine, and epidermis. Subcellular localization studies indicated that BmBras2 was predominantly localized in the nuclei of Bm5 cells, although cytoplasmic staining was also observed to a lesser extent. A cell proliferation assay showed that rBmBras2 could stimulate the proliferation of hepatoma cells. The higher BmBras2 expression levels in the pupal stage, tissue expression patterns, and a cell proliferation assay indicated that BmBras2 promotes cell division and proliferation, most likely by influencing cell signal transduction.

Frequencies of micro-nucleated lymphocytes and Epstein-Barr virus contamination in Altay region residents living near the Semipalatinsk atomic testing ground

International Nuclear Information System (INIS)

Ilyinskikh, N.N.; Ilyinskikh, E.N.; Yurkin, A.Yu.; Ilyinskikh, I.N.

2003-01-01

We have assessed frequencies of micro-nucleated lymphocytes in 3036 individuals living in 16 settlements in the west of the Altay region. Among the settlements the majority of individuals with significantly high frequencies of micro-nucleated lymphocytes were detected in settlements adjacent to the Semipalatinsk atomic testing ground (SATG). The most considerable genome instability was found in the individuals born in the period of intensive testing on the SATG (from 1949 to 1962). Moreover, we have determined that the residents of the settlements adjacent to the SATG have significantly high levels of antibodies to potentially oncogenic Epstein-Barr virus besides high frequencies of micro-nucleated lymphocytes. The considerable Epstein-Barr virus contamination among the residents in the radiation polluted zone around the SATG was supposed to be caused by immunodeficiency disorders in these individuals and induce high frequencies of micro-nucleated cells. (author)

Hepatitis C Virus core+1/ARF Protein Modulates the Cyclin D1/pRb Pathway and Promotes Carcinogenesis.

Science.gov (United States)

Moustafa, Savvina; Karakasiliotis, Ioannis; Mavromara, Penelope

2018-05-01

Viruses often encompass overlapping reading frames and unconventional translation mechanisms in order to maximize the output from a minimum genome and to orchestrate their timely gene expression. Hepatitis C virus (HCV) possesses such an unconventional open reading frame (ORF) within the core-coding region, encoding an additional protein, initially designated ARFP, F, or core+1. Two predominant isoforms of core+1/ARFP have been reported, core+1/L, initiating from codon 26, and core+1/S, initiating from codons 85/87 of the polyprotein coding region. The biological significance of core+1/ARFP expression remains elusive. The aim of the present study was to gain insight into the functional and pathological properties of core+1/ARFP through its interaction with the host cell, combining in vitro and in vivo approaches. Our data provide strong evidence that the core+1/ARFP of HCV-1a stimulates cell proliferation in Huh7-based cell lines expressing either core+1/S or core+1/L isoforms and in transgenic liver disease mouse models expressing core+1/S protein in a liver-specific manner. Both isoforms of core+1/ARFP increase the levels of cyclin D1 and phosphorylated Rb, thus promoting the cell cycle. In addition, core+1/S was found to enhance liver regeneration and oncogenesis in transgenic mice. The induction of the cell cycle together with increased mRNA levels of cell proliferation-related oncogenes in cells expressing the core+1/ARFP proteins argue for an oncogenic potential of these proteins and an important role in HCV-associated pathogenesis. IMPORTANCE This study sheds light on the biological importance of a unique HCV protein. We show here that core+1/ARFP of HCV-1a interacts with the host machinery, leading to acceleration of the cell cycle and enhancement of liver carcinogenesis. This pathological mechanism(s) may complement the action of other viral proteins with oncogenic properties, leading to the development of hepatocellular carcinoma. In addition, given that

Mitotic Stress Is an Integral Part of the Oncogene-Induced Senescence Program that Promotes Multinucleation and Cell Cycle Arrest

Directory of Open Access Journals (Sweden)

Dina Dikovskaya

2015-09-01

Full Text Available Oncogene-induced senescence (OIS is a tumor suppression mechanism that blocks cell proliferation in response to oncogenic signaling. OIS is frequently accompanied by multinucleation; however, the origin of this is unknown. Here, we show that multinucleate OIS cells originate mostly from failed mitosis. Prior to senescence, mutant H-RasV12 activation in primary human fibroblasts compromised mitosis, concordant with abnormal expression of mitotic genes functionally linked to the observed mitotic spindle and chromatin defects. Simultaneously, H-RasV12 activation enhanced survival of cells with damaged mitoses, culminating in extended mitotic arrest and aberrant exit from mitosis via mitotic slippage. ERK-dependent transcriptional upregulation of Mcl1 was, at least in part, responsible for enhanced survival and slippage of cells with mitotic defects. Importantly, mitotic slippage and oncogene signaling cooperatively induced senescence and key senescence effectors p21 and p16. In summary, activated Ras coordinately triggers mitotic disruption and enhanced cell survival to promote formation of multinucleate senescent cells.

New acute transforming feline retovirus with fms homology specifies a C-terminally truncated version of the c-fms protein that is different from SM-feline sarcoma virus v-fms protein

International Nuclear Information System (INIS)

Besmer, P.; Lader, E.; George, P.C.; Bergold, P.J.; Qui, F.; Zuckerman, E.E.; Hardy, W.D.

1986-01-01

The HZ5-feline sarcoma virus (FeSV) is a new acute transforming feline retrovirus which was isolated from a multicentric fibrosarcoma of a domestic cat. The HZ5-FeSV transforms fibroblasts in vitro and is replication defective. A biologically active integrated HZ5-FeSV provirus was molecularly cloned from cellular DNA of HZ5-FeSV-infected FRE-3A rat cells. The HZ5-FeSV has oncogene homology with the fms sequences of the SM-FeSV. The genome organization of the 8.6-kilobase HZ5-FeSV provirus is 5' Δgag-fms-Δpol-Δenv 3'. The HZ5- and SM-FeSVs display indistinguishable in vitro transformation characteristics, and the structures of the gag-fms transforming genes in the two viruses are very similar. In the HZ5-FeSV and the SM-FeSV, identical c-fms and feline leukemia virus p10 sequences form the 5' gag-fms junction. With regard to v-fms the two viruses are homologous up to 11 amino acids before the C terminus of the SM-FeSV v-fms protein. In HZ5-FeSV a segment of 362 nucleotides then follows before the 3' recombination site with feline leukemia virus pol. The new 3' v-fms sequence encodes 27 amino acids before reaching a TGA termination signal. The relationship of this sequence with the recently characterized human c-fms sequence has been examined. The 3' HZ5-FeSV v-fms sequence is homologous with 3' c-fms sequences. A frameshift mutation (11-base-pair deletion) was found in the C-terminal fms coding sequence of the HZ5-FeSV. As a result, the HZ5-FeSV v-fms protein is predicted to be a C-terminally truncated version of c-fms. This frameshift mutation may determine the oncogenic properties of v-fms in the HZ5-FeSV

New acute transforming feline retovirus with fms homology specifies a C-terminally truncated version of the c-fms protein that is different from SM-feline sarcoma virus v-fms protein

Energy Technology Data Exchange (ETDEWEB)

Besmer, P.; Lader, E.; George, P.C.; Bergold, P.J.; Qui, F.; Zuckerman, E.E.; Hardy, W.D.

1986-10-01

The HZ5-feline sarcoma virus (FeSV) is a new acute transforming feline retrovirus which was isolated from a multicentric fibrosarcoma of a domestic cat. The HZ5-FeSV transforms fibroblasts in vitro and is replication defective. A biologically active integrated HZ5-FeSV provirus was molecularly cloned from cellular DNA of HZ5-FeSV-infected FRE-3A rat cells. The HZ5-FeSV has oncogene homology with the fms sequences of the SM-FeSV. The genome organization of the 8.6-kilobase HZ5-FeSV provirus is 5' ..delta..gag-fms-..delta..pol-..delta..env 3'. The HZ5- and SM-FeSVs display indistinguishable in vitro transformation characteristics, and the structures of the gag-fms transforming genes in the two viruses are very similar. In the HZ5-FeSV and the SM-FeSV, identical c-fms and feline leukemia virus p10 sequences form the 5' gag-fms junction. With regard to v-fms the two viruses are homologous up to 11 amino acids before the C terminus of the SM-FeSV v-fms protein. In HZ5-FeSV a segment of 362 nucleotides then follows before the 3' recombination site with feline leukemia virus pol. The new 3' v-fms sequence encodes 27 amino acids before reaching a TGA termination signal. The relationship of this sequence with the recently characterized human c-fms sequence has been examined. The 3' HZ5-FeSV v-fms sequence is homologous with 3' c-fms sequences. A frameshift mutation (11-base-pair deletion) was found in the C-terminal fms coding sequence of the HZ5-FeSV. As a result, the HZ5-FeSV v-fms protein is predicted to be a C-terminally truncated version of c-fms. This frameshift mutation may determine the oncogenic properties of v-fms in the HZ5-FeSV.

Caracterización clínica e histopatológica de la infección por Papiloma Virus humano de muestras de cérvix. Hospital Teodoro Maldonado Carbo “IESS”

Directory of Open Access Journals (Sweden)

Bedoya, César

2017-08-01

Full Text Available Human Papilloma Virus (HPV has a predilection for poly-stratified tissues, with persistence in the basal layers, hence mainly is the etiological agent of cervical cancer. Cervical cancer is the second most common cancer in women worldwide. HPV is unique oncogenic infectious agent that causes it. The objective of the study was to determine the prevalence of the virus in women, using DNA detection techniques through PCR, in real-time, from the cervical biopsy. In addition, the related histopathological and clinical characteristics were established. The prevalence was 30.67%, the most frequently infected histopathology presentation was cervical and in situ cancer. The more dysplastic the histopathology of the cervix, the more frequent the presentation of the virus. An association between exposure to infection and the presence of whitish vaginal discharge and dyspareunia was demonstrated.

Characterizing the histopathology of natural co-infection with Marek's disease virus and subgroup J avian leucosis virus in egg-laying hens.

Science.gov (United States)

Wen, Yawen; Huang, Qi; Yang, Chengcheng; Pan, Ling; Wang, Guijun; Qi, Kezong; Liu, Hongmei

2018-02-01

Marek's disease virus (MDV) and avian leucosis virus (ALV) are known to cause tumours in egg-laying hens. Here, we investigated the aetiology of tumours in a flock of egg-laying hens vaccinated against MDV. We carried out gross pathology and histopathological examinations of the diseased tissues, identified virus antigen and sequenced viral oncogenes to elucidate the cause of death in 21-22-week-old hens. At necropsy, diseased hens had distinctly swollen livers, spleens, and proventriculus, and white tumour nodules in the liver. The spleen and liver had been infiltrated by lymphoid tumour cells, while the proventriculus had been infiltrated by both lymphoid tumour cells and myeloblastic cells. Subtype J ALV (ALV-J) and MDV were widely distributed in the proventricular gland cells, and the lymphoid tumour cells in the liver and the spleen. In addition, positive ALV-J signals were also observed in parts of the reticular cells in the spleen. MDV and ALV-J antigens were observed in the same foci of the proventricular gland cells; however, the two antigens were not observed in the same foci from the spleen and liver. The amino acid sequence of the AN-1 (the representative liver tumour tissue that was positive for both ALV-J and MDV) Meq protein was highly similar to the very virulent MDV QD2014 from China. Compared to the ALV-J HPRS-103 reference strain, 10 amino acids (224-CTTEWNYYAY-233) were deleted from the gp85 protein of AN-1. We concluded that concurrent infection with MDV and ALV-J contributed to the tumorigenicity observed in the flock.

Oncogenic Radiation Abscopal Effects In Vivo: Interrogating Mouse Skin

International Nuclear Information System (INIS)

Mancuso, Mariateresa; Leonardi, Simona; Giardullo, Paola; Pasquali, Emanuela; Tanori, Mirella; De Stefano, Ilaria; Casciati, Arianna; Naus, Christian C.; Pazzaglia, Simonetta; Saran, Anna

2013-01-01

Purpose: To investigate the tissue dependence in transmission of abscopal radiation signals and their oncogenic consequences in a radiosensitive mouse model and to explore the involvement of gap junction intercellular communication (GJIC) in mediating radiation tumorigenesis in off-target mouse skin. Methods and Materials: Patched1 heterozygous (Ptch1 +/− ) mice were irradiated at postnatal day 2 (P2) with 10 Gy of x-rays. Individual lead cylinders were used to protect the anterior two-thirds of the body, whereas the hindmost part was directly exposed to radiation. To test the role of GJICs and their major constituent connexin43 (Cx43), crosses between Ptch1 +/− and Cx43 +/− mice were similarly irradiated. These mouse groups were monitored for their lifetime, and skin basal cell carcinomas (BCCs) were counted and recorded. Early responses to DNA damage - Double Strand Breaks (DSBs) and apoptosis - were also evaluated in shielded and directly irradiated skin areas. Results: We report abscopal tumor induction in the shielded skin of Ptch1 +/− mice after partial-body irradiation. Endpoints were induction of early nodular BCC-like tumors and macroscopic infiltrative BCCs. Abscopal tumorigenesis was significantly modulated by Cx43 status, namely, Cx43 reduction was associated with decreased levels of DNA damage and oncogenesis in out-of-field skin, suggesting a key role of GJIC in transmission of oncogenic radiation signals to unhit skin. Conclusions: Our results further characterize the nature of abscopal responses and the implications they have on pathologic processes in different tissues, including their possible underlying mechanistic bases

Oncogenic Radiation Abscopal Effects In Vivo: Interrogating Mouse Skin

Energy Technology Data Exchange (ETDEWEB)

Mancuso, Mariateresa, E-mail: mariateresa.mancuso@enea.it [Laboratory of Radiation Biology and Biomedicine, Agenzia Nazionale per le Nuove Tecnologie, l' Energia e lo Sviluppo Economico Sostenibile (ENEA), Casaccia Research Centre, Rome (Italy); Leonardi, Simona [Laboratory of Radiation Biology and Biomedicine, Agenzia Nazionale per le Nuove Tecnologie, l' Energia e lo Sviluppo Economico Sostenibile (ENEA), Casaccia Research Centre, Rome (Italy); Giardullo, Paola; Pasquali, Emanuela [Department of Radiation Physics, Guglielmo Marconi University, Rome (Italy); Tanori, Mirella [Laboratory of Radiation Biology and Biomedicine, Agenzia Nazionale per le Nuove Tecnologie, l' Energia e lo Sviluppo Economico Sostenibile (ENEA), Casaccia Research Centre, Rome (Italy); De Stefano, Ilaria [Department of Radiation Physics, Guglielmo Marconi University, Rome (Italy); Casciati, Arianna [Laboratory of Radiation Biology and Biomedicine, Agenzia Nazionale per le Nuove Tecnologie, l' Energia e lo Sviluppo Economico Sostenibile (ENEA), Casaccia Research Centre, Rome (Italy); Naus, Christian C. [Department of Cellular and Physiological Sciences, The Life Sciences Institute, University of British Columbia, Vancouver, British Columbia (Canada); Pazzaglia, Simonetta; Saran, Anna [Laboratory of Radiation Biology and Biomedicine, Agenzia Nazionale per le Nuove Tecnologie, l' Energia e lo Sviluppo Economico Sostenibile (ENEA), Casaccia Research Centre, Rome (Italy)

2013-08-01

Purpose: To investigate the tissue dependence in transmission of abscopal radiation signals and their oncogenic consequences in a radiosensitive mouse model and to explore the involvement of gap junction intercellular communication (GJIC) in mediating radiation tumorigenesis in off-target mouse skin. Methods and Materials: Patched1 heterozygous (Ptch1{sup +/−}) mice were irradiated at postnatal day 2 (P2) with 10 Gy of x-rays. Individual lead cylinders were used to protect the anterior two-thirds of the body, whereas the hindmost part was directly exposed to radiation. To test the role of GJICs and their major constituent connexin43 (Cx43), crosses between Ptch1{sup +/−} and Cx43{sup +/−} mice were similarly irradiated. These mouse groups were monitored for their lifetime, and skin basal cell carcinomas (BCCs) were counted and recorded. Early responses to DNA damage - Double Strand Breaks (DSBs) and apoptosis - were also evaluated in shielded and directly irradiated skin areas. Results: We report abscopal tumor induction in the shielded skin of Ptch1{sup +/−} mice after partial-body irradiation. Endpoints were induction of early nodular BCC-like tumors and macroscopic infiltrative BCCs. Abscopal tumorigenesis was significantly modulated by Cx43 status, namely, Cx43 reduction was associated with decreased levels of DNA damage and oncogenesis in out-of-field skin, suggesting a key role of GJIC in transmission of oncogenic radiation signals to unhit skin. Conclusions: Our results further characterize the nature of abscopal responses and the implications they have on pathologic processes in different tissues, including their possible underlying mechanistic bases.

Oncogenic signalling pathways in benign odontogenic cysts and tumours.

Science.gov (United States)

Diniz, Marina Gonçalves; Gomes, Carolina Cavalieri; de Sousa, Sílvia Ferreira; Xavier, Guilherme Machado; Gomez, Ricardo Santiago

2017-09-01

The first step towards the prevention of cancer is to develop an in-depth understanding of tumourigenesis and the molecular basis of malignant transformation. What drives tumour initiation? Why do most benign tumours fail to metastasize? Oncogenic mutations, previously considered to be the hallmark drivers of cancers, are reported in benign cysts and tumours, including those that have an odontogenic origin. Despite the presence of such alterations, the vast majority of odontogenic lesions are benign and never progress to the stage of malignant transformation. As these lesions are likely to develop due to developmental defects, it is possible that they harbour quiet genomes. Now the question arises - do they result from DNA replication errors? Specific candidate genes have been sequenced in odontogenic lesions, revealing recurrent BRAF mutation in the case of ameloblastoma, KRAS mutation in adenomatoid odontogenic tumours, PTCH1 mutation in odontogenic keratocysts, and CTNNB1 (Beta-catenin) mutation in calcifying odontogenic cysts. Studies on these benign and rare entities might reveal important information about the tumorigenic process and the mechanisms that hinder/halt neoplastic progression. This is because the role of relatively common oncogenic mutations seems to be context dependent. In this review, each mutation signature of the odontogenic lesion and the affected signalling pathways are discussed in the context of tooth development and tumorigenesis. Furthermore, behavioural differences between different types of odontogenic lesions are explored and discussed based on the molecular alteration described. This review also includes the employment of molecular results for guiding therapeutic approaches towards odontogenic lesions. Copyright © 2017 Elsevier Ltd. All rights reserved.

RNA epitranscriptomics: Regulation of infection of RNA and DNA viruses by N6 -methyladenosine (m6 A).

Science.gov (United States)

Tan, Brandon; Gao, Shou-Jiang

2018-04-26

N 6 -methyladenosine (m 6 A) was discovered 4 decades ago. However, the functions of m 6 A and the cellular machinery that regulates its changes have just been revealed in the last few years. m 6 A is an abundant internal mRNA modification on cellular RNA and is implicated in diverse cellular functions. Recent works have demonstrated the presence of m 6 A in the genomes of RNA viruses and transcripts of a DNA virus with either a proviral or antiviral role. Here, we first summarize what is known about the m 6 A "writers," "erasers," "readers," and "antireaders" as well as the role of m 6 A in mRNA metabolism. We then review how the replications of numerous viruses are enhanced and restricted by m 6 A with emphasis on the oncogenic DNA virus, Kaposi sarcoma-associated herpesvirus (KSHV), whose m 6 A epitranscriptome was recently mapped. In the context of KSHV, m 6 A and the reader protein YTHDF2 acts as an antiviral mechanism during viral lytic replication. During viral latency, KSHV alters m 6 A on genes that are implicated in cellular transformation and viral latency. Lastly, we discuss future studies that are important to further delineate the functions of m 6 A in KSHV latent and lytic replication and KSHV-induced oncogenesis. Copyright © 2018 John Wiley & Sons, Ltd.

Detection of polyomavirus simian virus 40 tumor antigen DNA in AIDS-related systemic non-Hodgkin lymphoma

Science.gov (United States)

Vilchez, Regis A.; Lednicky, John A.; Halvorson, Steven J.; White, Zoe S.; Kozinetz, Claudia A.; Butel, Janet S.

2002-01-01

Systemic non-Hodgkin lymphoma (S-NHL) is a common malignancy during HIV infection, and it is hypothesized that infectious agents may be involved in the etiology. Epstein-Barr virus DNA is found in <40% of patients with AIDS-related S-NHL, suggesting that other oncogenic viruses, such as polyomaviruses, may play a role in pathogenesis. We analyzed AIDS-related S-NHL samples, NHL samples from HIV-negative patients, peripheral blood leukocytes from HIV-infected and -uninfected patients without NHL, and lymph nodes without tumors from HIV-infected patients. Specimens were examined by polymerase chain reaction analysis with use of primers specific for an N-terminal region of the oncoprotein large tumor antigen ( T-ag ) gene conserved among all three polyomaviruses (simian virus 40 [SV40], JC virus, and BK virus). Polyomavirus T-ag DNA sequences, proven to be SV40-specific, were detected more frequently in AIDS-related S-NHL samples (6 of 26) than in peripheral blood leukocytes from HIV-infected patients (6 of 26 vs. 0 of 69; p =.0001), NHL samples from HIV-negative patients (6 of 26 vs. 0 of 10; p =.09), or lymph nodes (6 of 26 vs. 0 of 7; p =.16). Sequences of C-terminal T-ag DNA from SV40 were amplified from two AIDS-related S-NHL samples. Epstein-Barr virus DNA sequences were detected in 38% (10 of 26) AIDS-related S-NHL samples, 50% (5 of 10) HIV-negative S-NHL samples, and 57% (4 of 7) lymph nodes. None of the S-NHL samples were positive for both Epstein-Barr virus DNA and SV40 DNA. Further studies of the possible role of SV40 in the pathogenesis of S-NHL are warranted.

Induction of uterine cancer with inactivated herpes simplex virus, types 1 and 2

International Nuclear Information System (INIS)

Wentz, W.B.; Reagan, J.W.; Heggie, A.D.; Fu, Y.S.; Anthony, D.D.

1981-01-01

A series of studies were performed to evaluate the oncogenic potential of inactivated herpes simplex viruses types 1 (HSV-1) and 2 (HSV-2) in the mouse cervix. HSV-1 or HSV-2 prepared in HEp-2 cell cultures and inactivated by exposure to formalin or ultraviolet light was applied to the mouse cervix for periods ranging from 20 to 90 weeks. Control mice were exposed for the same period to control fluids. Vaginal cytologic preparations from all animals were examined weekly to detect epithelial abnormalities. Animals were sacrificed and histopathological studies were carried out when cellular changes seen on vaginal smears resembled those indicative of premalignant or malignant changes as previously established in a similar model system using coal tar hydrocarbons. Other animals were exposed for periods up to 90 weeks, or until there was cellular evidence of invasive cancer. Cytologic and histologic materials were coded and evaluated without knowledge of whether they were from virus-exposed or control animals. Premalignant and malignant cervical lesions similar to those that occur in women were encountered in 78 to 90% of the virus-exposed animals. All controls were normal. Invasive cancer was detected in 24 to 60% of the animals and dysplasia was found in 18 to 66%. The yield of invasive cancer was twice as great after exposure to ultraviolet-inactivated HSV-2 as compared with formalin-inactivated virus. Various histologic grades of carcinoma of the cervix and endometrium were found. No primary lesions were found in the vagina or ovaries

Gain-of-function mutant p53 but not p53 deletion promotes head and neck cancer progression in response to oncogenic K-ras

Science.gov (United States)

Acin, Sergio; Li, Zhongyou; Mejia, Olga; Roop, Dennis R; El-Naggar, Adel K; Caulin, Carlos

2015-01-01

Mutations in p53 occur in over 50% of the human head and neck squamous cell carcinomas (SCCHN). The majority of these mutations result in the expression of mutant forms of p53, rather than deletions in the p53 gene. Some p53 mutants are associated with poor prognosis in SCCHN patients. However, the molecular mechanisms that determine the poor outcome of cancers carrying p53 mutations are unknown. Here, we generated a mouse model for SCCHN and found that activation of the endogenous p53 gain-of-function mutation p53R172H, but not deletion of p53, cooperates with oncogenic K-ras during SCCHN initiation, accelerates oral tumour growth, and promotes progression to carcinoma. Mechanistically, expression profiling of the tumours that developed in these mice and studies using cell lines derived from these tumours determined that mutant p53 induces the expression of genes involved in mitosis, including cyclin B1 and cyclin A, and accelerates entry in mitosis. Additionally, we discovered that this oncogenic function of mutant p53 was dependent on K-ras because the expression of cyclin B1 and cyclin A decreased, and entry in mitosis was delayed, after suppressing K-ras expression in oral tumour cells that express p53R172H. The presence of double-strand breaks in the tumours suggests that oncogene-dependent DNA damage resulting from K-ras activation promotes the oncogenic function of mutant p53. Accordingly, DNA damage induced by doxorubicin also induced increased expression of cyclin B1 and cyclin A in cells that express p53R172H. These findings represent strong in vivo evidence for an oncogenic function of endogenous p53 gain-of-function mutations in SCCHN and provide a mechanistic explanation for the genetic interaction between oncogenic K-ras and mutant p53. PMID:21952947

Therapeutic potential of oncolytic Newcastle disease virus: a critical review.

Science.gov (United States)

Tayeb, Shay; Zakay-Rones, Zichria; Panet, Amos

2015-01-01

Newcastle disease virus (NDV) features a natural preference for replication in many tumor cells compared with normal cells. The observed antitumor effect of NDV appears to be a result of both selective killing of tumor cells and induction of immune responses. Genetic manipulations to change viral tropism and arming the virus with genes encoding for cytokines improved the oncolytic capacity of NDV. Several intracellular proteins in tumor cells, including antiapoptotic proteins (Livin) and oncogenic proteins (H-Ras), are relevant for the oncolytic activity of NDV. Defects in the interferon system, found in some tumor cells, also contribute to the oncolytic selectivity of NDV. Notwithstanding, NDV displays effective oncolytic activity in many tumor types, despite having intact interferon signaling. Taken together, several cellular systems appear to dictate the selective oncolytic activity of NDV. Some barriers, such as neutralizing antibodies elicited during NDV treatment and the extracellular matrix in tumor tissue appear to interfere with spread of NDV and reduce oncolysis. To further understand the oncolytic activity of NDV, we compared two NDV strains, ie, an attenuated virus (NDV-HUJ) and a pathogenic virus (NDV-MTH-68/H). Significant differences in amino acid sequence were noted in several viral proteins, including the fusion precursor (F0) glycoprotein, an important determinant of replication and pathogenicity. However, no difference in the oncolytic activity of the two strains was noted using human tumor tissues maintained as organ cultures or in mouse tumor models. To optimize virotherapy in clinical trials, we describe here a unique organ culture methodology, using a biopsy taken from a patient's tumor before treatment for ex vivo infection with NDV to determine the oncolytic potential on an individual basis. In conclusion, oncolytic NDV is an excellent candidate for cancer therapy, but more knowledge is needed to ensure success in clinical trials.

Cytogenetic damage, oncogenic transformation and p53 induction in human epithelial cells in response to irradiation

Science.gov (United States)

Armitage, Mark

Ionizing radiation can have several different effects on cells, some are almost instantaneous such as the generation of DNA damage, other cellular responses take a matter of minutes or hours - DNA repair protein induction/activation, and others may take months or even years to be manifested - carcinogenesis. Human epithelial cell lines derived from both normal, non-neoplastic tissues and from a malignant source were cultured in order to examine several effects of ionizing radiation on such cell types. Cells not from a malignant source were previously immortalized by viral infection or by transfection with viral sequences. Simian virus 40 immortalised uroepithelial cells (SV-HUC) were found to be approximately a factor of two fold more radioresistant than cells of malignant origin (T24) in terms of unrepaired clastogenic damage i.e. assessment of micronuclei levels following irradiation. SV-HUC lines unlike T24 cells are non-tumourigenic when inoculated into nude athymic mice. SV-HUC lines proved very resistant to full oncogenic transformation using radiation and chemical carcinogens. However, morphological alterations and decreased anchorage dependant growth was observed in post carcinogen treated cells after appropriate cell culture conditions were utilized. The progression from this phenotype to a fully tumourigenic one was not recorded in this study. The ability of ionizing radiation to induce increased levels of the nuclear phosphoprotein p53 was also assessed using several different cell lines. SV- HUC and T24 cell lines failed to exhibit any increased p53 stabilization following irradiation. One cell line, a human papilloma virus transformed line (HPV) did show an approximate two fold increase of the wild type p53 protein after treatment with radiation. Only the cell line HPV showed any cell cycle delay, resulting in accumulation of cells in the G2/M compartment in post irradiation cell cycle analysis. The status of p53 was also assessed i.e. wild type or

Using a Novel Transgenic Mouse Model to Study c-Myc Oncogenic Pathway in Castration Resistance and Chemoresistance of Prostate Cancer

Science.gov (United States)

2017-12-01

AWARD NUMBER: W81XWH-13-1-0162 TITLE: Using a Novel Transgenic Mouse Model to Study c -Myc Oncogenic Pathway in Castration Resistance and...DATES COVERED 15Sept2013 - 14Sept2017 4. TITLE AND SUBTITLE 5a. CONTRACT NUMBER Using a Novel Transgenic Mouse Model to Study c -Myc Oncogenic...ABSTRACT We previously made a PB-Cre4/Ai-Myc model for Cre-induced and androgen-independent expression of c -Myc and Luc2 in prostate. This is designed

Role of human papilloma virus-16 in the pathogenesis of oral lichen planus--an immunohistochemical study.

Science.gov (United States)

Pol, Chetan A; Ghige, Suvarna K; Gosavi, Suchitra R

2015-02-01

Oral lichen planus (OLP) is a common chronic inflammatory immune-mediated disease with an aetiopathogenesis associated with cell-mediated immunological dysfunction. It is possible that oral mucosal viral infections, including human papilloma virus-16 (HPV-16) infection, may have a causative role in OLP pathogenesis. To assess the prevalence of HPV-16 in histopathologically diagnosed specimens of OLP and to evaluate whether any clinical features (such as the localisation of specimens) or the age or gender of patients, are correlated with the presence of this virus. This study was conducted on 30 specimens with a histopathological diagnosis of OLP, using the immunohistochemical marker HPV-16. Thirty normal oral mucosa specimens were also included as controls. Brown nuclear staining was accepted as positive for the HPV-16 antibody. The results were analysed using Fisher's exact test. P values<0.05 were considered to be significant. Significant correlation (P=0.0001) was observed between HPV-16 infection and samples with OLP. No statistical conclusions could be drawn regarding age, gender, localisation and HPV-16 positivity. Our study showed that HPV-16 may play a role in the pathogenesis of OLP. Taking into account the oncogenic potential of HPV-16, patients with OLP should be screened for the presence of this virus. © 2014 FDI World Dental Federation.

A New Crucial Protein Interaction Element That Targets the Adenovirus E4-ORF1 Oncoprotein to Membrane Vesicles▿

OpenAIRE

Chung, Sang-Hyuk; Frese, Kristopher K.; Weiss, Robert S.; Prasad, B. V. Venkataram; Javier, Ronald T.

2007-01-01

Human adenovirus type 9 exclusively elicits mammary tumors in experimental animals, and the primary oncogenic determinant of this virus is the E4-ORF1 oncogene, as opposed to the well-known E1A and E1B oncogenes. The tumorigenic potential of E4-ORF1, as well as its ability to oncogenically stimulate phosphatidylinositol 3-kinase (PI3K), depends on a carboxyl-terminal PDZ domain-binding motif (PBM) that mediates interactions with several different membrane-associated cellular PDZ proteins, inc...

Nicotine-mediated suppression of the retinoic acid metabolizing enzyme CYP26A1 limits the oncogenic potential of breast cancer.

Science.gov (United States)

Osanai, Makoto; Lee, Gang-Hong

2011-06-01

Tobacco smoke influences cancer development in tissues that are not directly exposed, and epidemiological studies have indicated that smoking women might experience decreased risk of breast cancer as a result of antiestrogenic effects. However, it remains to be clarified whether nicotine, one of the major addictive and best-investigated constituents of tobacco smoke, has any effect on breast cancer. Our recent work demonstrated that the retinoic acid metabolizing enzyme CYP26A1 enhances oncogenic and cell survival properties of breast carcinoma cells, implying a role as an oncogene. Here, we present evidence that nicotine significantly suppresses constitutive expression of CYP26A1, and that cells treated with nicotine exhibit enhanced sensitivity to apoptosis. In addition, nicotine may inhibit anchorage independent growth, cellular invasiveness and motility. These data show that nicotine can limit CYP26A1-mediated oncogenic characteristics, and suggest mechanisms by which nicotine might inhibit breast cancer development. © 2011 Japanese Cancer Association.

High-Risk Human Papillomaviral Oncogenes E6 and E7 Target Key Cellular Pathways to Achieve Oncogenesis.

Science.gov (United States)

Yeo-Teh, Nicole S L; Ito, Yoshiaki; Jha, Sudhakar

2018-06-08

Infection with high-risk human papillomavirus (HPV) has been linked to several human cancers, the most prominent of which is cervical cancer. The integration of the viral genome into the host genome is one of the manners in which the viral oncogenes E6 and E7 achieve persistent expression. The most well-studied cellular targets of the viral oncogenes E6 and E7 are p53 and pRb, respectively. However, recent research has demonstrated the ability of these two viral factors to target many more cellular factors, including proteins which regulate epigenetic marks and splicing changes in the cell. These have the ability to exert a global change, which eventually culminates to uncontrolled proliferation and carcinogenesis.

FACTORES PRONOSTICOS DEL CANCER DE MAMA Y ONCOGEN HER2/NEU

Directory of Open Access Journals (Sweden)

F.J. Martín Gil

2006-08-01

Full Text Available ABSTRACT: PRONOSTIC FACTORS OF BREAST CANCER AND HER2/NEUThe breast cancer constitutes the main cause of death by cancer in women of our country. In spite of the efforts directed in campaigns of precocious detection, the incidence continues increasing in a 1% approximately per year and the rate of mortality stay constant. Therefore it is of great importance to consolidate efforts directed towards the development and use of therapeutic and diagnostic methods. The development of neoplasia is directly related to successive genetic mutations in which cellular oncogenes are involved.It is known that in case of breast cancer the Her2/neu oncogene (Human epidermal growth receptor-2 factor is amplified and/or overexpressed in approximately a 30% of the cases. The knowledge of a positive result for Her2/neu overexpression has an important value in prognosis as it is associated to a greater aggressiveness of the disease. Also, this gene can be an answer marker to certain treatments like trastuzumab. RESUMEN:El cáncer de mama (CM constituye la principal causa de muerte por cáncer en mujeres de nuestro país. A pesar de los esfuerzos dirigidos hacia las campañas de detección precoz, la incidencia sigue aumentando aproximadamente en un 1% por año y la tasa de mortalidad sigue manteniéndose constante.Es por ello de gran importancia aunar esfuerzos dirigidos al desarrollo y utilización de métodos diagnósticos y terapéuticos. El desarrollo de una neoplasia está directamente relacionado con mutaciones genéticas sucesivas en las que están involucrados oncogenes celulares.En el caso del cáncer de mama se sabe que el encogen Her2/neu (Human epidermal growth factor receptor-2 está amplificado y/o sobreexpresado en aproximadamente un 30% de los casos. El conocimiento de la positividad del mismo tiene un importante valor pronóstico asociándose a una mayor agresividad de la enfermedad. Así mismo dicho gen puede ser un marcador predictivo de respuesta

The non-small cell lung cancer EGFR extracellular domain mutation, M277E, is oncogenic and drug-sensitive

Directory of Open Access Journals (Sweden)

Yu S

2017-09-01

Full Text Available Su Yu,1,2 Yang Zhang,1 Yunjian Pan,1 Chao Cheng,1,3 Yihua Sun,1,3 Haiquan Chen1–4 1Department of Thoracic Surgery, Fudan University Shanghai Cancer Center, Shanghai, China; 2Cancer Research Center, Fudan University Shanghai Cancer Center, Shanghai, China; 3Department of Oncology, Shanghai Medical College, Fudan University, Shanghai, China; 4Institutes of Biomedical Sciences, Fudan University, Shanghai, China Purpose: To identify novel oncogenic mutations in non-small cell lung cancer patient specimens that lack mutations in known targetable genes (“pan-negative” patients.Methods: Comprehensive mutational analyses were performed on 1,356 lung adenocarcinoma specimens. In this cohort of patients, common lung cancer oncogenic driver mutations were detected in the epidermal growth factor receptor (EGFR kinase domain, the human epidermal growth factor receptor 2 kinase domain, as well as the KRAS, BRAF, ALK, ROS1 and RET genes. A sub-cohort of pan-negative patient specimens was assayed for mutations in the EGFR extracellular domain (ECD. Additionally, EGFR mutant NIH-3T3 stable cell lines were constructed and assessed for protein content, anchorage-independent growth, and tumor formation in xenograft models to identify oncogenic mutations. BaF3 lymphocytes were also used to test sensitivities of the mutations to tyrosine kinase inhibitors.Results: In pan-negative lung adenocarcinoma cases, a novel oncogenic EGFR ECD mutation was identified (M277E. EGFR M277E mutations encoded oncoproteins that transformed NIH-3T3 cells to grow in the absence of exogenous epidermal growth factor. Transformation was further evidenced by anchorage-independent growth and tumor formation in immunocompromised xenograft mouse models. Finally, as seen in the canonical EGFR L858R mutation, the M277E mutation conferred sensitivity to both erlotinib and cetuximab in BaF3 cell lines and to erlotinib in xenograft models.Conclusion: Here, a new EGFR driver mutation, M277E

Pro-oncogene Pokemon promotes breast cancer progression by upregulating survivin expression

OpenAIRE

Zu, Xuyu; Ma, Jun; Liu, Hongxia; Liu, Feng; Tan, Chunyan; Yu, Lingling; Wang, Jue; Xie, Zhenhua; Cao, Deliang; Jiang, Yuyang

2011-01-01

Introduction Pokemon is an oncogenic transcription factor involved in cell growth, differentiation and oncogenesis, but little is known about its role in human breast cancer. In this study, we aimed to reveal the role of Pokemon in breast cancer progression and patient survival and to understand its underlying mechanisms. Methods Tissue microarray analysis of breast cancer tissues from patients with complete clinicopathological data and more than 20 years of follow-up were used to evaluate Po...

Occurrence and properties of antibodies against virus-associated transformation proteins in radiation-induced osteosarcomas in mice

International Nuclear Information System (INIS)

Hofherr, J.

1983-01-01

In this thesis it was looked if there is an immunresponse against such viral oncogene products in mice with radiation-induced osteosarcomas. Sera from mice with transplantable radiation-induced osteosacomas showed strong cytotoxicity against cells from a Moloney sarcoma virus-induced tumor and to a smaller extent also against FBJ osteosarcoma virus-transformed nonproducer cells. The cytotoxic activity was bound to the IgM fraction of the sera. Immunprecipitation of 35 S-methionine labelled virus- or radiation-transformed cells with cytotoxic sera showed on PAGE two proteins of molecular weights (m.w.) of about 50-55 kD. A protein of about 38 kD was expressed only in transformed cells whereas another protein of about 43 kD was seen in all cells except in uninfected muscle cells of adult mice. In order to further characterize the nature of these antigens immunprecipitates with unlabelled cells were tested in a protein kinase assay with gamma 32 P ATP and analysed on PAGE. Phosphorylation of proteins occured predominantly of more than 70 kD m.w., of about 68 kD, 50-55 kD and to a lesser extent also of about 32, 34 and 39 kD. The phosphorylation site of the proteins was at serine and threonine residues. These results indicate that mice with radiation-induced osteosarkomas develop antibodies against 'in vivo' and 'in vitro'-sarcoma virus transformed cells. (orig./MG) [de

A comparison of oncogene-induced senescence and replicative senescence: implications for tumor suppression and aging.

Science.gov (United States)

Nelson, David M; McBryan, Tony; Jeyapalan, Jessie C; Sedivy, John M; Adams, Peter D

2014-06-01

Cellular senescence is a stable proliferation arrest associated with an altered secretory pathway, the senescence-associated secretory phenotype. However, cellular senescence is initiated by diverse molecular triggers, such as activated oncogenes and shortened telomeres, and is associated with varied and complex physiological endpoints, such as tumor suppression and tissue aging. The extent to which distinct triggers activate divergent modes of senescence that might be associated with different physiological endpoints is largely unknown. To begin to address this, we performed gene expression profiling to compare the senescence programs associated with two different modes of senescence, oncogene-induced senescence (OIS) and replicative senescence (RS [in part caused by shortened telomeres]). While both OIS and RS are associated with many common changes in gene expression compared to control proliferating cells, they also exhibit substantial differences. These results are discussed in light of potential physiological consequences, tumor suppression and aging.

The oncogenic potential of three different 7, 12-dimethylbenz (a)anthracene transformed C3H/10T1/2 cell clones at various passages and the importance of the mode of immunosuppression

International Nuclear Information System (INIS)

Saxholm, H.J.K.

1979-01-01

The oncogenic potential of C3H/10T1/2 cells which were transformed in vitro with 7,12-dimethylbenz(a)anthracene is reported. The ability of the cells to grow as malignant tumors in syngeneic immunosuppressed mice was used as parameter for oncogenic potential. Cells of types I, II and III were assayed at several dosage levels, i.e., 10 4 , 10 5 or 10 6 cells per inoculum, with or without immunosuppression by antithymocyte serum globulin fraction. The studies were performed in several strains of host animals, i.e., male and female syngeneic C3H mice supplied by the National Cancer Institute, C3H mice supplied by Charles River and nude, athymic female mice. Morphological transformation preceded oncological transformation, and type I cells could not be established as tumors. Type II and type III cells developed oncogenic potential only after several passages in culture. Oncogenic potential was pronounced in the type III cells, and less strongly expressed in type II cells. Also tested were different methods of immunosuppression of the animal against the expression of the oncogenic potential of DMBA transformed C3H/10T1/2 cells from type II and III clones. Immunosuppression by antithymocyte serum globulin fraction was an effective method of preparing the syngeneic host so that cells with a low oncogenic potential would grow as tumors, whereas total body irradiation was not effective. For cells with a high oncogenic potential both ways of immunosuppression were sufficient. Admixing lethally irradiated cells in the cell inoculum slightly enhanced the tumor development from cells with low oncogenic potential and such addition was clearly effective for cells with a higher oncogenic potential, both for the antibody-treated and for the irradiated series. The findings were reproducible. The study stresses the importance of immunosuppression by antithymocyte globulins for detecting in vitro transformed weakly oncogenic cells. (author)

Pathology of fatal lineage 1 and 2 West Nile virus infections in horses in South Africa

Directory of Open Access Journals (Sweden)

June H. Williams

2014-09-01

Full Text Available Since 2007, West Nile virus (WNV has been reported in South African horses, causing severe neurological signs. All cases were of lineage 2, except for one case that clustered with lineage 1 viruses. In the present study, gross and microscopic lesions of six South African lineage 2-infected horses and the one lineage 1 case are described. Diagnoses were confirmed by real-time reverse-transcriptase polymerase chain reaction (RT-PCR of central nervous system (CNS tissue and one by RT-PCR of a brain virus isolate. The CNS of all cases was negative by RT-PCR or immunohistochemistry (IHC for African horse sickness (AHS, equine encephalosis virus, equine herpes viruses 1 and 4, other zoonotic flaviviruses, alphaviruses, and shunivirus, and either by immunofluorescence or IHC for rabies. Gross visceral lesions were nonspecific but often mimicked those of AHS. The CNS histopathology of WNV lineage 2 cases resembled the nonsuppurative polioencephalomyelitis reported in the Northern Hemisphere lineage 1 and recent Hungarian lineage 2 cases. Occasional meningitis, focal spinal ventral horn poliomalacia, dorsal and lateral horn poliomyelitis, leucomyelitis, asymmetrical ventral motor spinal neuritis and frequent olfactory region involvement were also seen. Lineage 2 cases displayed marked variations in CNS lesion severity, type and distribution, and suggested various viral entry routes into the CNS, based on findings in experimental mice and hamsters. Lineage 1 lesions were comparable to the milder lineage 2 cases. West Nile virus IHC on CNS sections with marked lesions from all cases elicited only two antigen-positive cells in the olfactory cortex of one case. The presence in the CNS of T-lymphocytes, B-lymphocytes, plasma cells and macrophage-monocytes was confirmed by cluster of differentiation (CD 3, CD20, multiple myeloma oncogene 1 (MUM1 and macrophage (MAC 387 IHC.

Influence of a ras oncogene on platelet-derived growth factor (PDGF)-stimulated phosphoinositide hydrolysis in murine fibroblasts

International Nuclear Information System (INIS)

Parries, G.; Racker, E.

1986-01-01

The authors have examined the effects of transfection of rat-1 fibroblasts with the ras oncogene on the metabolism of phosphatidylinositol (PI). Incubation of [ 3 H]inositol-labeled rat-1 cells with PDGF resulted in a 2- to 3-fold increase in [ 3 H]IP3 levels within 90 s. In the presence of 25 mM Li+, [ 3 H]IP1 levels were increased 8-fold after 30 min. In contrast, incubation of ras-transfected fibroblasts (EJ-2 line) with PDGF had little or no effect on the level of either [ 3 H]IP3 or [ 3 H]IP1. Similar stimulations by PDGF were observed in NIH 3T3 cells, but not in Kirsten virus-transformed or Harvey ras-transfected cell lines. On the other hand, NIH 3T3 cells transfected with v-src responded to PDGF by stimulation of PI turnover similar to the parent cell line. In NIH 3T3 cells transfected with an expression vector containing the v-Ha-ras gene under transcriptional control of the glucocorticoid-inducible mouse mammary tumor virus promoter, the PDGF stimulation of [ 3 H]inositol incorporation into PI was reduced from 10-fold in the absence of dexamethasone to 1.8-fold when the cells were pretreated for 26 h with 2 μM dexamethasone. In the parental 3T3 cells PDGF stimulation was reduced by about 40% in the presence of dexamethasone. In the absence of PDGF the rate of PI turnover (i.e., the kinetics of [ 3 H]IP1 accumulation in the presence of Li+) in EJ-2 cells was similar to that in rat-1 cells. Thus, in the presence of PDGF, the rate of PI turnover in rat-1 cells was several fold higher than in the transfected cells. These results suggest that the ras gene product (p21) may exert an inhibitory effect on PDGF-stimulated phosphoinositide metabolism

Cytological and oncogene alterations in radiation-transformed Syrian hamster embryo cells

International Nuclear Information System (INIS)

Trutschler, K.; Hieber, L.; Kellerer, A.M.

1991-01-01

Syrian hamster embryo (SHE) cells were neoplastically transformed by different types of ionizing radiation (γ-rays, α-particles or carbon ions). Transformed and tumor cell lines (derived from nude mice tumors) were analysed for alterations of the oncogenes c-Ha-ras and c-myc, i.e. RFLPs, gene amplifications, activation by point mutation, gene expression, and for cytological changes. In addition, the chromosome number and the numbers of micronuclei per cell have been determined in a series of cell lines. (author)

Frequency of twelve carcinogenic human papilloma virus types among women from the South Backa region, Vojvodina, Serbia.

Science.gov (United States)

Kovacevic, Gordana; Nikolic, Natasa; Jovanovic-Galovic, Aleksandra; Hrnjakovic-Cvjetkovic, Iv; Vuleta, Dusan; Patic, Aleksandra; Radovanov, Jelena; Milosevic, Vesna

2016-01-05

The aim of this study was to determine the presence and age distribution of different oncogenic human papilloma virus (HPV) types in women in the South Backa region and its relationship to Pap results. In a group of 1087 women with normal and abnormal cytology, the commercial HR HPV Real-TM kit (Sacace Biotechnologies, Italy) was used. Overall, 50.5% of the women were HPV positive. The presence of HPV types 18, 31, 51, and 58 was significantly influenced by age, while the presence of HPV types 16 and 45 was significantly influenced by cervical cytology. Results of the LSD test show a wide spectrum of high risk HPV among women with normal cytology and women with a low grade cervical lesion rate (atypical squamous cell of undetermined significance (ASCUS) and low grade squamous intraepithelial lesions (LSIL). The most prevalent HPV types found were 16, 31, 51, 18, and 52. In the HSIL group the most prevalent HPV types were 16 and 45. The reported results provide new data on the circulation of oncogenic HPV genotypes and frequency of multiple infections among women in Vojvodina and suggest that a prophylactic vaccine against HPV 16 and 18 has the potential to prevent approximately half of the high-grade lesions.

Prevalence of human papilloma virus infection in pregnant Turkish women compared with non-pregnant women.

Science.gov (United States)

Aydin, Y; Atis, A; Tutuman, T; Goker, N

2010-01-01

We aimed to find a prevalence of human papilloma virus (HPV) in order to define the 100 genotypes and subset of 14 oncogenic genotypes in pregnant Turkish women and to compare these with non-pregnant women. Cervical thin-prep specimens were obtained from 164 women in the first trimester pregnancy and 153 non pregnant women. 29.2% of pregnant versus 19.6% of non-pregnant Turkish women had at least one of the 100 types of HPV infection--a statistically significant difference. The rate of 14 high-risk HPV genotype infections was significantly higher in pregnant (14.6) compared to non-pregnant Turkish women (9.6%). Pregnant Turkish women are at higher risk for all HPV infections including high-risk cervical cancer genotypes.

A single oncogenic enhancer rearrangement causes concomitant EVI1 and GATA2 deregulation in leukemia

NARCIS (Netherlands)

Gröschel, Stefan; Sanders, Mathijs A; Hoogenboezem, Remco; de Wit, Elzo; Bouwman, Britta A M; Erpelinck, Claudia; van der Velden, Vincent H J; Havermans, Marije; Avellino, Roberto; van Lom, Kirsten; Rombouts, Elwin J; van Duin, Mark; Döhner, Konstanze; Beverloo, H Berna; Bradner, James E; Döhner, Hartmut; Löwenberg, Bob; Valk, Peter J M; Bindels, Eric M J; de Laat, Wouter; Delwel, Ruud

2014-01-01

Chromosomal rearrangements without gene fusions have been implicated in leukemogenesis by causing deregulation of proto-oncogenes via relocation of cryptic regulatory DNA elements. AML with inv(3)/t(3;3) is associated with aberrant expression of the stem-cell regulator EVI1. Applying functional

BRAF and RAS oncogenes regulate Rho GTPase pathways to mediate migration and invasion properties in human colon cancer cells: a comparative study

Directory of Open Access Journals (Sweden)

Shirasawa Senji

2011-09-01

Full Text Available Abstract Background Colorectal cancer is a common disease that involves genetic alterations, such as inactivation of tumour suppressor genes and activation of oncogenes. Among them are RAS and BRAF mutations, which rarely coexist in the same tumour. Individual members of the Rho (Ras homology GTPases contribute with distinct roles in tumour cell morphology, invasion and metastasis. The aim of this study is to dissect cell migration and invasion pathways that are utilised by BRAFV600E as compared to KRASG12V and HRASG12V oncoproteins. In particular, the role of RhoA (Ras homolog gene family, member A, Rac1 (Ras-related C3 botulinum toxin substrate 1 and Cdc42 (cell division cycle 42 in cancer progression induced by each of the three oncogenes is described. Methods Colon adenocarcinoma cells with endogenous as well as ectopically expressed or silenced oncogenic mutations of BRAFV600E, KRASG12V and HRASG12V were employed. Signalling pathways and Rho GTPases were inhibited with specific kinase inhibitors and siRNAs. Cell motility and invasion properties were correlated with cytoskeletal properties and Rho GTPase activities. Results Evidence presented here indicate that BRAFV600E significantly induces cell migration and invasion properties in vitro in colon cancer cells, at least in part through activation of RhoA GTPase. The relationship established between BRAFV600E and RhoA activation is mediated by the MEK-ERK pathway. In parallel, KRASG12V enhances the ability of colon adenocarcinoma cells Caco-2 to migrate and invade through filopodia formation and PI3K-dependent Cdc42 activation. Ultimately increased cell migration and invasion, mediated by Rac1, along with the mesenchymal morphology obtained through the Epithelial-Mesenchymal Transition (EMT were the main characteristics rendered by HRASG12V in Caco-2 cells. Moreover, BRAF and KRAS oncogenes are shown to cooperate with the TGFβ-1 pathway to provide cells with additional transforming

Understanding the Role of Intrinsic Disorder of Viral Proteins in the Oncogenicity of Different Types of HPV.

Science.gov (United States)

Tamarozzi, Elvira Regina; Giuliatti, Silvana

2018-01-09

Intrinsic disorder is very important in the biological function of several proteins, and is directly linked to their foldability during interaction with their targets. There is a close relationship between the intrinsically disordered proteins and the process of carcinogenesis involving viral pathogens. Among these pathogens, we have highlighted the human papillomavirus (HPV) in this study. HPV is currently among the most common sexually transmitted infections, besides being the cause of several types of cancer. HPVs are divided into two groups, called high- and low-risk, based on their oncogenic potential. The high-risk HPV E6 protein has been the target of much research, in seeking treatments against HPV, due to its direct involvement in the process of cell cycle control. To understand the role of intrinsic disorder of the viral proteins in the oncogenic potential of different HPV types, the structural characteristics of intrinsically disordered regions of high and low-risk HPV E6 proteins were analyzed. In silico analyses of primary sequences, prediction of tertiary structures, and analyses of molecular dynamics allowed the observation of the behavior of such disordered regions in these proteins, thereby proving a direct relationship of structural variation with the degree of oncogenicity of HPVs. The results obtained may contribute to the development of new therapies, targeting the E6 oncoprotein, for the treatment of HPV-associated diseases.

Tumor-Promoting Circuits That Regulate a Cancer-Related Chemokine Cluster: Dominance of Inflammatory Mediators Over Oncogenic Alterations

International Nuclear Information System (INIS)

Leibovich-Rivkin, Tal; Buganim, Yosef; Solomon, Hilla; Meshel, Tsipi; Rotter, Varda; Ben-Baruch, Adit

2012-01-01

Here, we investigated the relative contribution of genetic/signaling components versus microenvironmental factors to the malignancy phenotype. In this system, we took advantage of non-transformed fibroblasts that carried defined oncogenic modifications in Ras and/or p53. These cells were exposed to microenvironmental pressures, and the expression of a cancer-related chemokine cluster was used as readout for the malignancy potential (CCL2, CCL5, CXCL8, CXCL10). In cells kept in-culture, synergism between Ras hyper-activation and p53 dysfunction was required to up-regulate the expression of the chemokine cluster. The in vivo passage of Ras High /p53 Low -modified cells has led to tumor formation, accompanied by potentiation of chemokine release, implicating a powerful role for the tumor microenvironment in up-regulating the chemokine cluster. Indeed, we found that inflammatory mediators which are prevalent in tumor sites, such as TNFα and IL-1β, had a predominant impact on the release of the chemokines, which was substantially higher than that obtained by the oncogenic modifications alone, possibly acting through the transcription factors AP-1 and NF-κB. Together, our results propose that in the unbiased model system that we were using, inflammatory mediators of the tumor milieu have dominating roles over oncogenic modifications in dictating the expression of a pro-malignancy chemokine readout

Induction of Epstein-Barr Virus Oncoprotein LMP1 by Transcription Factors AP-2 and Early B Cell Factor

Science.gov (United States)

Noda, Chieko; Narita, Yohei; Watanabe, Takahiro; Yoshida, Masahiro; Ashio, Keiji; Sato, Yoshitaka; Goshima, Fumi; Kanda, Teru; Yoshiyama, Hironori; Tsurumi, Tatsuya; Kimura, Hiroshi

2016-01-01

ABSTRACT Latent membrane protein 1 (LMP1) is a major oncogene essential for primary B cell transformation by Epstein-Barr virus (EBV). Previous studies suggested that some transcription factors, such as PU.1, RBP-Jκ, NF-κB, and STAT, are involved in this expression, but the underlying mechanism is unclear. Here, we identified binding sites for PAX5, AP-2, and EBF in the proximal LMP1 promoter (ED-L1p). We first confirmed the significance of PU.1 and POU domain transcription factor binding for activation of the promoter in latency III. We then focused on the transcription factors AP-2 and early B cell factor (EBF). Interestingly, among the three AP-2-binding sites in the LMP1 promoter, two motifs were also bound by EBF. Overexpression, knockdown, and mutagenesis in the context of the viral genome indicated that AP-2 plays an important role in LMP1 expression in latency II in epithelial cells. In latency III B cells, on the other hand, the B cell-specific transcription factor EBF binds to the ED-L1p and activates LMP1 transcription from the promoter. IMPORTANCE Epstein-Barr virus (EBV) latent membrane protein 1 (LMP1) is crucial for B cell transformation and oncogenesis of other EBV-related malignancies, such as nasopharyngeal carcinoma and T/NK lymphoma. Its expression is largely dependent on the cell type or condition, and some transcription factors have been implicated in its regulation. However, these previous reports evaluated the significance of specific factors mostly by reporter assay. In this study, we prepared point-mutated EBV at the binding sites of such transcription factors and confirmed the importance of AP-2, EBF, PU.1, and POU domain factors. Our results will provide insight into the transcriptional regulation of the major oncogene LMP1. PMID:26819314

Synergistic Induction of Potential Warburg Effect in Zebrafish Hepatocellular Carcinoma by Co-Transgenic Expression of Myc and xmrk Oncogenes.

Directory of Open Access Journals (Sweden)

Zhen Li

Full Text Available Previously we have generated inducible liver tumor models by transgenic expression of Myc or xmrk (activated EGFR homolog oncogenes in zebrafish. To investigate the interaction of the two oncogenes, we crossed the two transgenic lines and observed more severe and faster hepatocarcinogenesis in Myc/xmrk double transgenic zebrafish than either single transgenic fish. RNA-Seq analyses revealed distinct changes in many molecular pathways among the three types of liver tumors. In particular, we found dramatic alteration of cancer metabolism based on the uniquely enriched pathways in the Myc/xmrk tumors. Critical glycolytic genes including hk2, pkm and ldha were significantly up-regulated in Myc/xmrk tumors but not in either single oncogene-induced tumors, suggesting a potential Warburg effect. In RT-qPCR analyses, the specific pkm2 isoformin Warburg effect was found to be highly enriched in the Myc/xmrk tumors but not in Myc or xmrk tumors, consistent with the observations in many human cancers with Warburg effect. Moreover, the splicing factor genes (hnrnpa1, ptbp1a, ptbp1b and sfrs3b responsible for generating the pkm isoform were also greatly up-regulated in the Myc/xmrk tumors. As Pkm2 isoform is generally inactive and causes incomplete glycolysis to favor anabolism and tumor growth, by treatment with a Pkm2-specific activator, TEPP-46, we further demonstrated that activation of Pkm2 suppressed the growth of oncogenic liver as well as proliferation of liver cells. Collectively, our Myc/xmrk zebrafish model suggests synergetic effect of EGFR and MYC in triggering Warburg effect in the HCC formation and may provide a promising in vivo model for Warburg effect.

Expression of hepatocyte growth factor and the proto-oncogenic receptor c-Met in canine osteosarcoma

NARCIS (Netherlands)

Fieten, H; Spee, B; Ijzer, J; Kik, M J; Penning, L C; Kirpensteijn, J

Hepatocyte growth factor (HGF) and the proto-oncogenic receptor c-Met are implicated in growth, invasion, and metastasis in human cancer. Little information is available on the expression and role of both gene products in canine osteosarcoma. We hypothesized that the expression of c-Met is

The APC/C E3 Ligase Complex Activator FZR1 Restricts BRAF Oncogenic Function.

Science.gov (United States)

Wan, Lixin; Chen, Ming; Cao, Juxiang; Dai, Xiangpeng; Yin, Qing; Zhang, Jinfang; Song, Su-Jung; Lu, Ying; Liu, Jing; Inuzuka, Hiroyuki; Katon, Jesse M; Berry, Kelsey; Fung, Jacqueline; Ng, Christopher; Liu, Pengda; Song, Min Sup; Xue, Lian; Bronson, Roderick T; Kirschner, Marc W; Cui, Rutao; Pandolfi, Pier Paolo; Wei, Wenyi

2017-04-01

BRAF drives tumorigenesis by coordinating the activation of the RAS/RAF/MEK/ERK oncogenic signaling cascade. However, upstream pathways governing BRAF kinase activity and protein stability remain undefined. Here, we report that in primary cells with active APC FZR1 , APC FZR1 earmarks BRAF for ubiquitination-mediated proteolysis, whereas in cancer cells with APC-free FZR1, FZR1 suppresses BRAF through disrupting BRAF dimerization. Moreover, we identified FZR1 as a direct target of ERK and CYCLIN D1/CDK4 kinases. Phosphorylation of FZR1 inhibits APC FZR1 , leading to elevation of a cohort of oncogenic APC FZR1 substrates to facilitate melanomagenesis. Importantly, CDK4 and/or BRAF/MEK inhibitors restore APC FZR1 E3 ligase activity, which might be critical for their clinical effects. Furthermore, FZR1 depletion cooperates with AKT hyperactivation to transform primary melanocytes, whereas genetic ablation of Fzr1 synergizes with Pten loss, leading to aberrant coactivation of BRAF/ERK and AKT signaling in mice. Our findings therefore reveal a reciprocal suppression mechanism between FZR1 and BRAF in controlling tumorigenesis. Significance: FZR1 inhibits BRAF oncogenic functions via both APC-dependent proteolysis and APC-independent disruption of BRAF dimers, whereas hyperactivated ERK and CDK4 reciprocally suppress APC FZR1 E3 ligase activity. Aberrancies in this newly defined signaling network might account for BRAF hyperactivation in human cancers, suggesting that targeting CYCLIN D1/CDK4, alone or in combination with BRAF/MEK inhibition, can be an effective anti-melanoma therapy. Cancer Discov; 7(4); 424-41. ©2017 AACR. See related commentary by Zhang and Bollag, p. 356 This article is highlighted in the In This Issue feature, p. 339 . ©2017 American Association for Cancer Research.

Human Mut T Homolog 1 (MTH1): a roadblock for the tumor-suppressive effects of oncogenic RAS-induced ROS.

Science.gov (United States)

Rai, Priyamvada

2012-01-01

Oncogenic RAS-induced reactive oxygen species (ROS) trigger barriers to cell transformation and cancer progression through tumor-suppressive responses such as cellular senescence or cell death. We have recently shown that oncogenic RAS-induced DNA damage and attendant premature senescence can be prevented by overexpressing human MutT Homolog 1 (MTH1), the major mammalian detoxifier of the oxidized DNA precursor, 8-oxo-dGTP. Paradoxically, RAS-induced ROS are also able to participate in tumor progression via transformative processes such as mitogenic signaling, the epithelial-mesenchymal transition (EMT), anoikis inhibition, and PI3K/Akt-mediated survival signaling. Here we provide a preliminary insight into the influence of MTH1 levels on the EMT phenotype and Akt activation in RAS-transformed HMLE breast epithelial cells. Within this context, we will discuss the implications of MTH1 upregulation in oncogenic RAS-sustaining cells as a beneficial adaptive change that inhibits ROS-mediated cell senescence and participates in the maintenance of ROS-associated tumor-promoting mechanisms. Accordingly, targeting MTH1 in RAS-transformed tumor cells will not only induce proliferative defects but also potentially enhance therapeutic cytotoxicity by shifting cellular response away from pro-survival mechanisms.

Risk scaling factors from inactivation to chromosome aberrations, mutations and oncogenic transformations in mammalian cells

International Nuclear Information System (INIS)

Alkaharam, A.S.; Watt, D.E.

1997-01-01

Analyses of bio-effect mechanisms of damage to mammalian cells in terms of the quality parameter 'mean free path for primary ionisation', for heavy charged particles, strongly suggests that there is a common mechanism for the biological endpoints of chromosome aberrations, mutations and oncogenic transformation. The lethal lesions are identified as unrepaired double-strand breaks in the intracellular DNA. As data for the various endpoints studied can be represented in a unified scheme, for any radiation type, it follows that radiation risk factors can be determined on the basis of simple ratios to the inactivation cross sections. There are intrinsic physical reasons why neutrons can never reach the saturation level of heavier particles for equal fluences. The probabilities of risk with respect to inactivation, for chromosome dicentrics, mutation of the HPRT gene and of oncogenic transformation are respectively 0.24, 5.8 x 10 -5 , and 4.1 x 10 -3 . (author)

Pan-SRC kinase inhibition blocks B-cell receptor oncogenic signaling in non-Hodgkin lymphoma.

Science.gov (United States)

Battistello, Elena; Katanayeva, Natalya; Dheilly, Elie; Tavernari, Daniele; Donaldson, Maria C; Bonsignore, Luca; Thome, Margot; Christie, Amanda L; Murakami, Mark A; Michielin, Olivier; Ciriello, Giovanni; Zoete, Vincent; Oricchio, Elisa

2018-05-24

In diffuse large B-cell lymphoma (DLBCL), activation of the B-cell receptor (BCR) promotes multiple oncogenic signals, which are essential for tumor proliferation. Inhibition of the Bruton's tyrosine kinase (BTK), a BCR downstream target, is therapeutically effective only in a subgroup of patients with DLBCL. Here, we used lymphoma cells isolated from patients with DLBCL to measure the effects of targeted therapies on BCR signaling and to anticipate response. In lymphomas resistant to BTK inhibition, we show that blocking BTK activity enhanced tumor dependencies from alternative oncogenic signals downstream of the BCR, converging on MYC upregulation. To completely ablate the activity of the BCR, we genetically and pharmacologically repressed the activity of the SRC kinases LYN, FYN, and BLK, which are responsible for the propagation of the BCR signal. Inhibition of these kinases strongly reduced tumor growth in xenografts and cell lines derived from patients with DLBCL independent of their molecular subtype, advancing the possibility to be relevant therapeutic targets in broad and diverse groups of DLBCL patients. © 2018 by The American Society of Hematology.

Human papillomavirus prevalence and type distribution in 3603 HIV-positive and HIV-negative women in the general population of Tanzania

DEFF Research Database (Denmark)

Dartell, Myassa Arkam; Rasch, Vibeke; Kahesa, Crispin

2012-01-01

The aim of the Prevention of Cervical Cancer in Tanzania (PROTECT) study is to assess the prevalence of oncogenic human papillomavirus (HPV) and to determine the type distribution among women in the general population according to human immunodeficiency virus (HIV) status, in preparation for a po......The aim of the Prevention of Cervical Cancer in Tanzania (PROTECT) study is to assess the prevalence of oncogenic human papillomavirus (HPV) and to determine the type distribution among women in the general population according to human immunodeficiency virus (HIV) status, in preparation...

An Oncogenic Role for Alternative NF-κB Signaling in DLBCL Revealed upon Deregulated BCL6 Expression

Directory of Open Access Journals (Sweden)

Baochun Zhang

2015-05-01

Full Text Available Diffuse large B cell lymphoma (DLBCL is a complex disease comprising diverse subtypes and genetic profiles. Possibly because of the prevalence of genetic alterations activating canonical NF-κB activity, a role for oncogenic lesions that activate the alternative NF-κB pathway in DLBCL has remained elusive. Here, we show that deletion/mutation of TRAF3, a negative regulator of the alternative NF-κB pathway, occurs in ∼15% of DLBCLs and that it often coexists with BCL6 translocation, which prevents terminal B cell differentiation. Accordingly, in a mouse model constitutive activation of the alternative NF-κB pathway cooperates with BCL6 deregulation in DLBCL development. This work demonstrates a key oncogenic role for the alternative NF-κB pathway in DLBCL development.

Pan-cancer Alterations of the MYC Oncogene and Its Proximal Network across the Cancer Genome Atlas

NARCIS (Netherlands)

Schaub, Franz X.; Dhankani, Varsha; Berger, Ashton C.; Trivedi, Mihir; Richardson, Anne B.; Shaw, Reid; Zhao, Wei; Zhang, Xiaoyang; Ventura, Andrea; Liu, Yuexin; Ayer, Donald E.; Hurlin, Peter J.; Cherniack, Andrew D.; Eisenman, Robert N.; Bernard, Brady; Grandori, Carla; Caesar-Johnson, Samantha J.; Demchok, John A.; Felau, Ina; Kasapi, Melpomeni; Ferguson, Martin L.; Hutter, Carolyn M.; Sofia, Heidi J.; Tarnuzzer, Roy; Wang, Zhining; Yang, Liming; Zenklusen, Jean C.; Zhang, Jiashan (Julia); Chudamani, Sudha; Liu, Jia; Lolla, Laxmi; Naresh, Rashi; Pihl, Todd; Sun, Qiang; Wan, Yunhu; Wu, Ye; Cho, Juok; DeFreitas, Timothy; Frazer, Scott; Gehlenborg, Nils; Getz, Gad; Heiman, David I.; Kim, Jaegil; Lawrence, Michael S.; Lin, Pei; Meier, Sam; Noble, Michael S.; Saksena, Gordon; Voet, Doug; Zhang, Hailei; Bernard, Brady; Chambwe, Nyasha; Dhankani, Varsha; Knijnenburg, Theo; Kramer, Roger; Leinonen, Kalle; Liu, Yuexin; Miller, Michael; Reynolds, Sheila; Shmulevich, Ilya; Thorsson, Vesteinn; Zhang, Wei; Akbani, Rehan; Broom, Bradley M.; Hegde, Apurva M.; Ju, Zhenlin; Kanchi, Rupa S.; Korkut, Anil; Li, Jun; Liang, Han; Ling, Shiyun; Liu, Wenbin; Lu, Yiling; Mills, Gordon B.; Ng, Kwok Shing; Rao, Arvind; Ryan, Michael; Wang, Jing; Weinstein, John N.; Zhang, Jiexin; Abeshouse, Adam; Armenia, Joshua; Chakravarty, Debyani; Chatila, Walid K.; de Bruijn, Ino; Gao, Jianjiong; Gross, Benjamin E.; Heins, Zachary J.; Kundra, Ritika; La, Konnor; Ladanyi, Marc; Luna, Augustin; Nissan, Moriah G.; Ochoa, Angelica; Phillips, Sarah M.; Reznik, Ed; Sanchez-Vega, Francisco; Sander, Chris; Schultz, Nikolaus; Sheridan, Robert; Sumer, S. Onur; Sun, Yichao; Taylor, Barry S.; Wang, Jioajiao; Zhang, Hongxin; Anur, Pavana; Peto, Myron; Spellman, Paul; Benz, Christopher; Stuart, Joshua M.; Wong, Christopher K.; Yau, Christina; Hayes, D. Neil; Parker, Joel S.; Wilkerson, Matthew D.; Ally, Adrian; Balasundaram, Miruna; Bowlby, Reanne; Brooks, Denise; Carlsen, Rebecca; Chuah, Eric; Dhalla, Noreen; Holt, Robert; Jones, Steven J.M.; Kasaian, Katayoon; Lee, Darlene; Ma, Yussanne; Marra, Marco A.; Mayo, Michael; Moore, Richard A.; Mungall, Andrew J.; Mungall, Karen; Robertson, A. Gordon; Sadeghi, Sara; Schein, Jacqueline E.; Sipahimalani, Payal; Tam, Angela; Thiessen, Nina; Tse, Kane; Wong, Tina; Berger, Ashton C.; Beroukhim, Rameen; Cherniack, Andrew D.; Cibulskis, Carrie; Gabriel, Stacey B.; Gao, Galen F.; Ha, Gavin; Meyerson, Matthew; Schumacher, Steven E.; Shih, Juliann; Kucherlapati, Melanie H.; Kucherlapati, Raju S.; Baylin, Stephen; Cope, Leslie; Danilova, Ludmila; Bootwalla, Moiz S.; Lai, Phillip H.; Maglinte, Dennis T.; Van Den Berg, David J.; Weisenberger, Daniel J.; Auman, J. Todd; Balu, Saianand; Bodenheimer, Tom; Fan, Cheng; Hoadley, Katherine A.; Hoyle, Alan P.; Jefferys, Stuart R.; Jones, Corbin D.; Meng, Shaowu; Mieczkowski, Piotr A.; Mose, Lisle E.; Perou, Amy H.; Perou, Charles M.; Roach, Jeffrey; Shi, Yan; Simons, Janae V.; Skelly, Tara; Soloway, Matthew G.; Tan, Donghui; Veluvolu, Umadevi; Fan, Huihui; Hinoue, Toshinori; Laird, Peter W.; Shen, Hui; Zhou, Wanding; Bellair, Michelle; Chang, Kyle; Covington, Kyle; Creighton, Chad J.; Dinh, Huyen; Doddapaneni, Harsha Vardhan; Donehower, Lawrence A.; Drummond, Jennifer; Gibbs, Richard A.; Glenn, Robert; Hale, Walker; Han, Yi; Hu, Jianhong; Korchina, Viktoriya; Lee, Sandra; Lewis, Lora; Li, Wei; Liu, Xiuping; Morgan, Margaret; Morton, Donna; Muzny, Donna; Santibanez, Jireh; Sheth, Margi; Shinbrot, Eve; Wang, Linghua; Wang, Min; Wheeler, David A.; Xi, Liu; Zhao, Fengmei; Hess, Julian; Appelbaum, Elizabeth L.; Bailey, Matthew; Cordes, Matthew G.; Ding, Li; Fronick, Catrina C.; Fulton, Lucinda A.; Fulton, Robert S.; Kandoth, Cyriac; Mardis, Elaine R.; McLellan, Michael D.; Miller, Christopher A.; Schmidt, Heather K.; Wilson, Richard K.; Crain, Daniel; Curley, Erin; Gardner, Johanna; Lau, Kevin; Mallery, David; Morris, Scott; Paulauskis, Joseph; Penny, Robert; Shelton, Candace; Shelton, Troy; Sherman, Mark; Thompson, Eric; Yena, Peggy; Bowen, Jay; Gastier-Foster, Julie M.; Gerken, Mark; Leraas, Kristen M.; Lichtenberg, Tara M.; Ramirez, Nilsa C.; Wise, Lisa; Zmuda, Erik; Corcoran, Niall; Costello, Tony; Hovens, Christopher; Carvalho, Andre L.; de Carvalho, Ana C.; Fregnani, José H.; Longatto-Filho, Adhemar; Reis, Rui M.; Scapulatempo-Neto, Cristovam; Silveira, Henrique C.S.; Vidal, Daniel O.; Burnette, Andrew; Eschbacher, Jennifer; Hermes, Beth; Noss, Ardene; Singh, Rosy; Anderson, Matthew L.; Castro, Patricia D.; Ittmann, Michael; Huntsman, David; Kohl, Bernard; Le, Xuan; Thorp, Richard; Andry, Chris; Duffy, Elizabeth R.; Lyadov, Vladimir; Paklina, Oxana; Setdikova, Galiya; Shabunin, Alexey; Tavobilov, Mikhail; McPherson, Christopher; Warnick, Ronald; Berkowitz, Ross; Cramer, Daniel; Feltmate, Colleen; Horowitz, Neil; Kibel, Adam; Muto, Michael; Raut, Chandrajit P.; Malykh, Andrei; Barnholtz-Sloan, Jill S.; Barrett, Wendi; Devine, Karen; Fulop, Jordonna; Ostrom, Quinn T.; Shimmel, Kristen; Wolinsky, Yingli; Sloan, Andrew E.; De Rose, Agostino; Giuliante, Felice; Goodman, Marc; Karlan, Beth Y.; Hagedorn, Curt H.; Eckman, John; Harr, Jodi; Myers, Jerome; Tucker, Kelinda; Zach, Leigh Anne; Deyarmin, Brenda; Hu, Hai; Kvecher, Leonid; Larson, Caroline; Mural, Richard J.; Somiari, Stella; Vicha, Ales; Zelinka, Tomas; Bennett, Joseph; Iacocca, Mary; Rabeno, Brenda; Swanson, Patricia; Latour, Mathieu; Lacombe, Louis; Têtu, Bernard; Bergeron, Alain; McGraw, Mary; Staugaitis, Susan M.; Chabot, John; Hibshoosh, Hanina; Sepulveda, Antonia; Su, Tao; Wang, Timothy; Potapova, Olga; Voronina, Olga; Desjardins, Laurence; Mariani, Odette; Roman-Roman, Sergio; Sastre, Xavier; Stern, Marc Henri; Cheng, Feixiong; Signoretti, Sabina; Berchuck, Andrew; Bigner, Darell; Lipp, Eric; Marks, Jeffrey; McCall, Shannon; McLendon, Roger; Secord, Angeles; Sharp, Alexis; Behera, Madhusmita; Brat, Daniel J.; Chen, Amy; Delman, Keith; Force, Seth; Khuri, Fadlo; Magliocca, Kelly; Maithel, Shishir; Olson, Jeffrey J.; Owonikoko, Taofeek; Pickens, Alan; Ramalingam, Suresh; Shin, Dong M.; Sica, Gabriel; Van Meir, Erwin G.; Zhang, Hongzheng; Eijckenboom, Wil; Gillis, Ad; Korpershoek, Esther; Looijenga, Leendert; Oosterhuis, Wolter; Stoop, Hans; van Kessel, Kim E.; Zwarthoff, Ellen C.; Calatozzolo, Chiara; Cuppini, Lucia; Cuzzubbo, Stefania; DiMeco, Francesco; Finocchiaro, Gaetano; Mattei, Luca; Perin, Alessandro; Pollo, Bianca; Chen, Chu; Houck, John; Lohavanichbutr, Pawadee; Hartmann, Arndt; Stoehr, Christine; Stoehr, Robert; Taubert, Helge; Wach, Sven; Wullich, Bernd; Kycler, Witold; Murawa, Dawid; Wiznerowicz, Maciej; Chung, Ki; Edenfield, W. Jeffrey; Martin, Julie; Baudin, Eric; Bubley, Glenn; Bueno, Raphael; De Rienzo, Assunta; Richards, William G.; Kalkanis, Steven; Mikkelsen, Tom; Noushmehr, Houtan; Scarpace, Lisa; Girard, Nicolas; Aymerich, Marta; Campo, Elias; Giné, Eva; Guillermo, Armando López; Van Bang, Nguyen; Hanh, Phan Thi; Phu, Bui Duc; Tang, Yufang; Colman, Howard; Evason, Kimberley; Dottino, Peter R.; Martignetti, John A.; Gabra, Hani; Juhl, Hartmut; Akeredolu, Teniola; Stepa, Serghei; Hoon, Dave; Ahn, Keunsoo; Kang, Koo Jeong; Beuschlein, Felix; Breggia, Anne; Birrer, Michael; Bell, Debra; Borad, Mitesh; Bryce, Alan H.; Castle, Erik; Chandan, Vishal; Cheville, John; Copland, John A.; Farnell, Michael; Flotte, Thomas; Giama, Nasra; Ho, Thai; Kendrick, Michael; Kocher, Jean Pierre; Kopp, Karla; Moser, Catherine; Nagorney, David; O'Brien, Daniel; O'Neill, Brian Patrick; Patel, Tushar; Petersen, Gloria; Que, Florencia; Rivera, Michael; Roberts, Lewis; Smallridge, Robert; Smyrk, Thomas; Stanton, Melissa; Thompson, R. Houston; Torbenson, Michael; Yang, Ju Dong; Zhang, Lizhi; Brimo, Fadi; Ajani, Jaffer A.; Angulo Gonzalez, Ana Maria; Behrens, Carmen; Bondaruk, Jolanta; Broaddus, Russell; Czerniak, Bogdan; Esmaeli, Bita; Fujimoto, Junya; Gershenwald, Jeffrey; Guo, Charles; Lazar, Alexander J.; Logothetis, Christopher; Meric-Bernstam, Funda; Moran, Cesar; Ramondetta, Lois; Rice, David; Sood, Anil; Tamboli, Pheroze; Thompson, Timothy; Troncoso, Patricia; Tsao, Anne; Wistuba, Ignacio; Carter, Candace; Haydu, Lauren; Hersey, Peter; Jakrot, Valerie; Kakavand, Hojabr; Kefford, Richard; Lee, Kenneth; Long, Georgina; Mann, Graham; Quinn, Michael; Saw, Robyn; Scolyer, Richard; Shannon, Kerwin; Spillane, Andrew; Stretch, Jonathan; Synott, Maria; Thompson, John; Wilmott, James; Al-Ahmadie, Hikmat; Chan, Timothy A.; Ghossein, Ronald; Gopalan, Anuradha; Levine, Douglas A.; Reuter, Victor; Singer, Samuel; Singh, Bhuvanesh; Tien, Nguyen Viet; Broudy, Thomas; Mirsaidi, Cyrus; Nair, Praveen; Drwiega, Paul; Miller, Judy; Smith, Jennifer; Zaren, Howard; Park, Joong Won; Hung, Nguyen Phi; Kebebew, Electron; Linehan, W. Marston; Metwalli, Adam R.; Pacak, Karel; Pinto, Peter A.; Schiffman, Mark; Schmidt, Laura S.; Vocke, Cathy D.; Wentzensen, Nicolas; Worrell, Robert; Yang, Hannah; Moncrieff, Marc; Goparaju, Chandra; Melamed, Jonathan; Pass, Harvey; Botnariuc, Natalia; Caraman, Irina; Cernat, Mircea; Chemencedji, Inga; Clipca, Adrian; Doruc, Serghei; Gorincioi, Ghenadie; Mura, Sergiu; Pirtac, Maria; Stancul, Irina; Tcaciuc, Diana; Albert, Monique; Alexopoulou, Iakovina; Arnaout, Angel; Bartlett, John; Engel, Jay; Gilbert, Sebastien; Parfitt, Jeremy; Sekhon, Harman; Thomas, George; Rassl, Doris M.; Rintoul, Robert C.; Bifulco, Carlo; Tamakawa, Raina; Urba, Walter; Hayward, Nicholas; Timmers, Henri; Antenucci, Anna; Facciolo, Francesco; Grazi, Gianluca; Marino, Mirella; Merola, Roberta; de Krijger, Ronald; Gimenez-Roqueplo, Anne Paule; Piché, Alain; Chevalier, Simone; McKercher, Ginette; Birsoy, Kivanc; Barnett, Gene; Brewer, Cathy; Farver, Carol; Naska, Theresa; Pennell, Nathan A.; Raymond, Daniel; Schilero, Cathy; Smolenski, Kathy; Williams, Felicia; Morrison, Carl; Borgia, Jeffrey A.; Liptay, Michael J.; Pool, Mark; Seder, Christopher W.; Junker, Kerstin; Omberg, Larsson; Dinkin, Mikhail; Manikhas, George; Alvaro, Domenico; Bragazzi, Maria Consiglia; Cardinale, Vincenzo; Carpino, Guido; Gaudio, Eugenio; Chesla, David; Cottingham, Sandra; Dubina, Michael; Moiseenko, Fedor; Dhanasekaran, Renumathy; Becker, Karl Friedrich; Janssen, Klaus Peter; Slotta-Huspenina, Julia; Abdel-Rahman, Mohamed H.; Aziz, Dina; Bell, Sue; Cebulla, Colleen M.; Davis, Amy; Duell, Rebecca; Elder, J. Bradley; Hilty, Joe; Kumar, Bahavna; Lang, James; Lehman, Norman L.; Mandt, Randy; Nguyen, Phuong; Pilarski, Robert; Rai, Karan; Schoenfield, Lynn; Senecal, Kelly; Wakely, Paul; Hansen, Paul; Lechan, Ronald; Powers, James; Tischler, Arthur; Grizzle, William E.; Sexton, Katherine C.; Kastl, Alison; Henderson, Joel; Porten, Sima; Waldmann, Jens; Fassnacht, Martin; Asa, Sylvia L.; Schadendorf, Dirk; Couce, Marta; Graefen, Markus; Huland, Hartwig; Sauter, Guido; Schlomm, Thorsten; Simon, Ronald; Tennstedt, Pierre; Olabode, Oluwole; Nelson, Mark; Bathe, Oliver; Carroll, Peter R.; Chan, June M.; Disaia, Philip; Glenn, Pat; Kelley, Robin K.; Landen, Charles N.; Phillips, Joanna; Prados, Michael; Simko, Jeffry; Smith-McCune, Karen; VandenBerg, Scott; Roggin, Kevin; Fehrenbach, Ashley; Kendler, Ady; Sifri, Suzanne; Steele, Ruth; Jimeno, Antonio; Carey, Francis; Forgie, Ian; Mannelli, Massimo; Carney, Michael; Hernandez, Brenda; Campos, Benito; Herold-Mende, Christel; Jungk, Christin; Unterberg, Andreas; von Deimling, Andreas; Bossler, Aaron; Galbraith, Joseph; Jacobus, Laura; Knudson, Michael; Knutson, Tina; Ma, Deqin; Milhem, Mohammed; Sigmund, Rita; Godwin, Andrew K.; Madan, Rashna; Rosenthal, Howard G.; Adebamowo, Clement; Adebamowo, Sally N.; Boussioutas, Alex; Beer, David; Giordano, Thomas; Mes-Masson, Anne Marie; Saad, Fred; Bocklage, Therese; Landrum, Lisa; Mannel, Robert; Moore, Kathleen; Moxley, Katherine; Postier, Russel; Walker, Joan; Zuna, Rosemary; Feldman, Michael; Valdivieso, Federico; Dhir, Rajiv; Luketich, James; Mora Pinero, Edna M.; Quintero-Aguilo, Mario; Carlotti, Carlos Gilberto; Dos Santos, Jose Sebastião; Kemp, Rafael; Sankarankuty, Ajith; Tirapelli, Daniela; Catto, James; Agnew, Kathy; Swisher, Elizabeth; Creaney, Jenette; Robinson, Bruce; Shelley, Carl Simon; Godwin, Eryn M.; Kendall, Sara; Shipman, Cassaundra; Bradford, Carol; Carey, Thomas; Haddad, Andrea; Moyer, Jeffey; Peterson, Lisa; Prince, Mark; Rozek, Laura; Wolf, Gregory; Bowman, Rayleen; Fong, Kwun M.; Yang, Ian; Korst, Robert; Rathmell, W. Kimryn; Fantacone-Campbell, J. Leigh; Hooke, Jeffrey A.; Kovatich, Albert J.; Shriver, Craig D.; DiPersio, John; Drake, Bettina; Govindan, Ramaswamy; Heath, Sharon; Ley, Timothy; Van Tine, Brian; Westervelt, Peter; Rubin, Mark A.; Lee, Jung Il; Aredes, Natália D.; Mariamidze, Armaz

2018-01-01

Although the MYC oncogene has been implicated in cancer, a systematic assessment of alterations of MYC, related transcription factors, and co-regulatory proteins, forming the proximal MYC network (PMN), across human cancers is lacking. Using computational approaches, we define genomic and proteomic

Detection of Hepatocyte Clones Containing Integrated Hepatitis B Virus DNA Using Inverse Nested PCR.

Science.gov (United States)

Tu, Thomas; Jilbert, Allison R

2017-01-01

Chronic hepatitis B virus (HBV) infection is a major cause of liver cirrhosis and hepatocellular carcinoma (HCC), leading to ~600,000 deaths per year worldwide. Many of the steps that occur during progression from the normal liver to cirrhosis and/or HCC are unknown. Integration of HBV DNA into random sites in the host cell genome occurs as a by-product of the HBV replication cycle and forms a unique junction between virus and cellular DNA. Analyses of integrated HBV DNA have revealed that HCCs are clonal and imply that they develop from the transformation of hepatocytes, the only liver cell known to be infected by HBV. Integrated HBV DNA has also been shown, at least in some tumors, to cause insertional mutagenesis in cancer driver genes, which may facilitate the development of HCC. Studies of HBV DNA integration in the histologically normal liver have provided additional insight into HBV-associated liver disease, suggesting that hepatocytes with a survival or growth advantage undergo high levels of clonal expansion even in the absence of oncogenic transformation. Here we describe inverse nested PCR (invPCR), a highly sensitive method that allows detection, sequencing, and enumeration of virus-cell DNA junctions formed by the integration of HBV DNA. The invPCR protocol is composed of two major steps: inversion of the virus-cell DNA junction and single-molecule nested PCR. The invPCR method is highly specific and inexpensive and can be tailored to DNA extracted from large or small amounts of liver. This procedure also allows detection of genome-wide random integration of any known DNA sequence and is therefore a useful technique for molecular biology, virology, and genetic research.

ΔNp63α is an oncogene that induces Lsh expression and promotes stem-like proliferation

Science.gov (United States)

Keyes, William M.; Pecoraro, Matteo; Aranda, Victoria; Vernersson-Lindahl, Emma; Li, Wangzhi; Vogel, Hannes; Guo, Xuecui; Garcia, Elvin L.; Michurina, Tatyana V.; Enikolopov, Grigori; Muthuswamy, Senthil K.; Mills, Alea A.

2014-01-01

SUMMARY The p53 homolog p63 is essential for development, yet its role in cancer is not clear. We discovered that p63 deficiency evokes the tumor suppressive mechanism of cellular senescence, causing a striking absence of stratified epithelia such as the skin. Here we identify the predominant p63 isoform, ΔNp63α, as a protein that bypasses oncogene induced senescence to drive tumorigenesis in vivo. Interestingly, bypass of senescence promotes stem-like proliferation and maintains survival of the keratin 15-positive stem cell population. Furthermore, we identify the chromatin remodeling protein Lsh as a new target of ΔNp63α that is an essential mediator of senescence bypass. These findings indicate that ΔNp63α is an oncogene that cooperates with Ras to promote tumor-initiating stem-like proliferation, and suggest that Lsh-mediated chromatin remodeling events are critical to this process. PMID:21295273

Epstein-Barr virus ensures B cell survival by uniquely modulating apoptosis at early and late times after infection.

Science.gov (United States)

Price, Alexander M; Dai, Joanne; Bazot, Quentin; Patel, Luv; Nikitin, Pavel A; Djavadian, Reza; Winter, Peter S; Salinas, Cristina A; Barry, Ashley Perkins; Wood, Kris C; Johannsen, Eric C; Letai, Anthony; Allday, Martin J; Luftig, Micah A

2017-04-20

Latent Epstein-Barr virus (EBV) infection is causally linked to several human cancers. EBV expresses viral oncogenes that promote cell growth and inhibit the apoptotic response to uncontrolled proliferation. The EBV oncoprotein LMP1 constitutively activates NFκB and is critical for survival of EBV-immortalized B cells. However, during early infection EBV induces rapid B cell proliferation with low levels of LMP1 and little apoptosis. Therefore, we sought to define the mechanism of survival in the absence of LMP1/NFκB early after infection. We used BH3 profiling to query mitochondrial regulation of apoptosis and defined a transition from uninfected B cells (BCL-2) to early-infected (MCL-1/BCL-2) and immortalized cells (BFL-1). This dynamic change in B cell survival mechanisms is unique to virus-infected cells and relies on regulation of MCL-1 mitochondrial localization and BFL-1 transcription by the viral EBNA3A protein. This study defines a new role for EBNA3A in the suppression of apoptosis with implications for EBV lymphomagenesis.

Detection and genotyping of human papilloma virus in cervical cancer specimens from Saudi patients.

Science.gov (United States)

Al-Badawi, Ismail A; Al-Suwaine, Abdulrahman; Al-Aker, Murad; Asaad, Lina; Alaidan, Alwaleed; Tulbah, Asma; Fe Bohol, Marie; Munkarah, Adnan R

2011-07-01

To determine the rates and types of human papilloma virus (HPV) infection in cervical cancer specimens from Saudi patients. One hundred specimens were randomly selected and retrieved from the achieved samples stored in the pathology department accessioned under the diagnosis of cervical cancer and carcinoma in situ between the years 1997 and 2007. Human papilloma virus in the clinical samples was detected using polymerase chain reaction amplification methods. Two primer systems are commonly used: the MY09-MY11 primers and the GP5+-GP6+ that amplify a wide range of HPV genotypes. Human papilloma virus isolates were genotyped using DNA sequencing and reverse line blot hybridization assay to identify the high-risk HPV genotypes. Ninety cases fulfilled the diagnostic criteria and were analyzed. The rate of HPV genotype detection among cervical cancer samples was 95.5%. The most common HPV genotype detected by both methods was HPV-16 (63.4%), followed by HPV-18 (11.1%), HPV-45 (4.5%), HPV-33 (3.3%), and HPV-31, HPV-52, HPV-53, HPV-58, HPV-59, and HPV-66 with 2.2% prevalence rate each. Prevalence of HPV genotypes among patients with cervical cancer in Saudi Arabia is comparable to the international rates. The use of the reverse line blot hybridization assay genotyping method could be useful for classifying oncogenic HPV-positive women. It is relatively inexpensive and reliable and can be performed in routine practice or epidemiological study compared with the available standard commercial kits.

Ebola Virus and Marburg Virus

Science.gov (United States)

Ebola virus and Marburg virus Overview Ebola virus and Marburg virus are related viruses that cause hemorrhagic fevers — illnesses marked by severe bleeding (hemorrhage), organ failure and, in many ...

Study of the relationship virus of the human papilloma (VHP) and cancer of uterine neck

International Nuclear Information System (INIS)

Bravo, Maria Mercedes

1999-01-01

Today in day the narrow relationship is known among the viral infection by VHP and the cancer of uterine neck; in this pathology they also appear the proteins E6 and E7 that are target of oncogenes and important part in the course of cancer of uterine neck. It intends as hypothesis that when to a patient with neck cancer, it is administered radiotherapy, there is lysis tumoral that liberates viral components that then E7 acts on the proteins being given an immunologic answer of cellular type, activating clones. When the immunologic answer is positive, the results to the treatment are but favorable and vice versa. The objective was to determine if the virus is detected after the treatment with the radiotherapy and if the titles of antibodies had increased or diminished. An analysis of the age was made, of the size of the tumor, of the state and one of the virus of the papilloma was looked for before and after the treatment, quantifying the variation (increase or decrease) of its quantity, finally it was observed if the presage after the treatment was related with the patient's survival

Prediction of lung cells oncogenic transformation for induced radon progeny alpha particles using sugarscape cellular automata.

Science.gov (United States)

Baradaran, Samaneh; Maleknasr, Niaz; Setayeshi, Saeed; Akbari, Mohammad Esmaeil

2014-01-01

Alpha particle irradiation from radon progeny is one of the major natural sources of effective dose in the public population. Oncogenic transformation is a biological effectiveness of radon progeny alpha particle hits. The biological effects which has caused by exposure to radon, were the main result of a complex series of physical, chemical, biological and physiological interactions. The cellular and molecular mechanisms for radon-induced carcinogenesis have not been clear yet. Various biological models, including cultured cells and animals, have been found useful for studying the carcinogenesis effects of radon progeny alpha particles. In this paper, sugars cape cellular automata have been presented for computational study of complex biological effect of radon progeny alpha particles in lung bronchial airways. The model has included mechanism of DNA damage, which has been induced alpha particles hits, and then formation of transformation in the lung cells. Biomarkers were an objective measure or evaluation of normal or abnormal biological processes. In the model, the metabolism rate of infected cell has been induced alpha particles traversals, as a biomarker, has been followed to reach oncogenic transformation. The model results have successfully validated in comparison with "in vitro oncogenic transformation data" for C3H 10T1/2 cells. This model has provided an opportunity to study the cellular and molecular changes, at the various stages in radiation carcinogenesis, involving human cells. It has become well known that simulation could be used to investigate complex biomedical systems, in situations where traditional methodologies were difficult or too costly to employ.

Clonal composition of human ovarian cancer based on copy number analysis reveals a reciprocal relation with oncogenic mutation status.

Science.gov (United States)

Sakai, Kazuko; Ukita, Masayo; Schmidt, Jeanette; Wu, Longyang; De Velasco, Marco A; Roter, Alan; Jevons, Luis; Nishio, Kazuto; Mandai, Masaki

2017-10-01

Intratumoral heterogeneity of cancer cells remains largely unexplored. Here we investigated the composition of ovarian cancer and its biological relevance. A whole-genome single nucleotide polymorphism array was applied to detect the clonal composition of 24 formalin-fixed, paraffin-embedded samples of human ovarian cancer. Genome-wide segmentation data consisting of the log2 ratio (log2R) and B allele frequency (BAF) were used to calculate an estimate of the clonal composition number (CC number) for each tumor. Somatic mutation profiles of cancer-related genes were also determined for the same 24 samples by next-generation sequencing. The CC number was estimated successfully for 23 of the 24 cancer samples. The mean ± SD value for the CC number was 1.7 ± 1.1 (range of 0-4). A somatic mutation in at least one gene was identified in 22 of the 24 ovarian cancer samples, with the mutations including those in the oncogenes KRAS (29.2%), PIK3CA (12.5%), BRAF (8.3%), FGFR2 (4.2%), and JAK2 (4.2%) as well as those in the tumor suppressor genes TP53 (54.2%), FBXW7 (8.3%), PTEN (4.2%), and RB1 (4.2%). Tumors with one or more oncogenic mutations had a significantly lower CC number than did those without such a mutation (1.0 ± 0.8 versus 2.3 ± 0.9, P = 0.0027), suggesting that cancers with driver oncogene mutations are less heterogeneous than those with other mutations. Our results thus reveal a reciprocal relation between oncogenic mutation status and clonal composition in ovarian cancer using the established method for the estimation of the CC number. Copyright © 2017 The Author(s). Published by Elsevier B.V. All rights reserved.

Energy parasites trigger oncogene mutation

Czech Academy of Sciences Publication Activity Database

Pokorný, Jiří; Pokorný, Jan; Jandová, Anna; Kobilková, J.; Vrba, J.; Vrba, J. jr.

2016-01-01

Roč. 92, č. 10 (2016), s. 577-582 ISSN 0955-3002 R&D Projects: GA ČR GA16-12757S Institutional support: RVO:68378271 ; RVO:67985882 Keywords : cancer initiation * cell-mediated immunity * coherent electromagnetic states * genome somatic mutation * LDH virus * parasitic energy consumption Subject RIV: BO - Biophysics Impact factor: 1.992, year: 2016

Overexpression of the human DEK oncogene reprograms cellular metabolism and promotes glycolysis

Science.gov (United States)

Watanabe, Miki; Muraleedharan, Ranjithmenon; Lambert, Paul F.; Lane, Andrew N.; Romick-Rosendale, Lindsey E.; Wells, Susanne I.

2017-01-01

The DEK oncogene is overexpressed in many human malignancies including at early tumor stages. Our reported in vitro and in vivo models of squamous cell carcinoma have demonstrated that DEK contributes functionally to cellular and tumor survival and to proliferation. However, the underlying molecular mechanisms remain poorly understood. Based on recent RNA sequencing experiments, DEK expression was necessary for the transcription of several metabolic enzymes involved in anabolic pathways. This identified a possible mechanism whereby DEK may drive cellular metabolism to enable cell proliferation. Functional metabolic Seahorse analysis demonstrated increased baseline and maximum extracellular acidification rates, a readout of glycolysis, in DEK-overexpressing keratinocytes and squamous cell carcinoma cells. DEK overexpression also increased the maximum rate of oxygen consumption and therefore increased the potential for oxidative phosphorylation (OxPhos). To detect small metabolites that participate in glycolysis and the tricarboxylic acid cycle (TCA) that supplies substrate for OxPhos, we carried out NMR-based metabolomics studies. We found that high levels of DEK significantly reprogrammed cellular metabolism and altered the abundances of amino acids, TCA cycle intermediates and the glycolytic end products lactate, alanine and NAD+. Taken together, these data support a scenario whereby overexpression of the human DEK oncogene reprograms keratinocyte metabolism to fulfill energy and macromolecule demands required to enable and sustain cancer cell growth. PMID:28558019

Overexpression of the human DEK oncogene reprograms cellular metabolism and promotes glycolysis.

Directory of Open Access Journals (Sweden)

Marie C Matrka

Full Text Available The DEK oncogene is overexpressed in many human malignancies including at early tumor stages. Our reported in vitro and in vivo models of squamous cell carcinoma have demonstrated that DEK contributes functionally to cellular and tumor survival and to proliferation. However, the underlying molecular mechanisms remain poorly understood. Based on recent RNA sequencing experiments, DEK expression was necessary for the transcription of several metabolic enzymes involved in anabolic pathways. This identified a possible mechanism whereby DEK may drive cellular metabolism to enable cell proliferation. Functional metabolic Seahorse analysis demonstrated increased baseline and maximum extracellular acidification rates, a readout of glycolysis, in DEK-overexpressing keratinocytes and squamous cell carcinoma cells. DEK overexpression also increased the maximum rate of oxygen consumption and therefore increased the potential for oxidative phosphorylation (OxPhos. To detect small metabolites that participate in glycolysis and the tricarboxylic acid cycle (TCA that supplies substrate for OxPhos, we carried out NMR-based metabolomics studies. We found that high levels of DEK significantly reprogrammed cellular metabolism and altered the abundances of amino acids, TCA cycle intermediates and the glycolytic end products lactate, alanine and NAD+. Taken together, these data support a scenario whereby overexpression of the human DEK oncogene reprograms keratinocyte metabolism to fulfill energy and macromolecule demands required to enable and sustain cancer cell growth.

USP22 acts as an oncogene by regulating the stability of cyclooxygenase-2 in non-small cell lung cancer

Energy Technology Data Exchange (ETDEWEB)

Xiao, Haibo [Department of Cardiothoracic Surgery, Xinhua Hospital, School of Medicine, Shanghai Jiaotong University, Shanghai 200092 (China); Tian, Yue [Institute of Orthopaedics, Chinese PLA General Hospital, Beijing 100853 (China); Yang, Yang; Hu, Fengqing; Xie, Xiao; Mei, Ju [Department of Cardiothoracic Surgery, Xinhua Hospital, School of Medicine, Shanghai Jiaotong University, Shanghai 200092 (China); Ding, Fangbao, E-mail: drnail@sina.com [Department of Cardiothoracic Surgery, Xinhua Hospital, School of Medicine, Shanghai Jiaotong University, Shanghai 200092 (China)

2015-05-08

The histone ubiquitin hydrolase ubiquitin-specific protease 22 (USP22) is an epigenetic modifier and an oncogene that is upregulated in many types of cancer. In non-small cell lung cancer (NSCLC), aberrant expression of USP22 is a predictor of poor survival, as is high expression of cyclooxygenase-2 (COX-2). Despite its oncogenic role, few substrates of USP22 have been identified and its mechanism of action in cancer remains unclear. Here, we identified COX-2 as a direct substrate of USP22 and showed that its levels are modulated by USP22 mediated deubiquitination. Silencing of USP22 downregulated COX-2, decreased its half-life, and inhibited lung carcinoma cell proliferation by directly interacting with and modulating the stability and activity of COX-2 through the regulation of its ubiquitination status. The findings of the present study suggest a potential mechanism underlying the oncogenic role of USP22 mediated by the modulation of the stability and activity of COX-2. - Highlights: • USP22 interacts with COX-2. • USP22 deubiquitinates and stabilizes COX-2. • USP22 is required for COX-2-mediated upregulation of prostaglandin E2.

The Therapeutic Potential of CRISPR/Cas9 Systems in Oncogene-Addicted Cancer Types: Virally Driven Cancers as a Model System

Directory of Open Access Journals (Sweden)

Luqman Jubair

2017-09-01

Full Text Available The field of gene editing is undergoing unprecedented growth. The first ex vivo human clinical trial in China started in 2016, more than 1000 US patents have been filed, and there is exponential growth in publications. The ability to edit genes with high fidelity is promising for the development of new treatments for a range of diseases, particularly inherited conditions, infectious diseases, and cancers. For cancer, a major issue is the identification of driver mutations and oncogenes to target for therapeutic effect, and this requires the development of robust models with which to prove their efficacy. The challenge is that there is rarely a single critical gene. However, virally driven cancers, in which cells are addicted to the expression of a single viral oncogene in some cases, may serve as model systems for CRISPR/Cas therapies, as they did for RNAi. These models and systems offer an excellent opportunity to test both preclinical models and clinical conditions to examine the effectiveness of gene editing, and here we review the options and offer a way forward. Keywords: CRISPR/Cas9, virally-driven cancers, cervical cancer, oncogene-addiction

Co-chaperone BAG2 Determines the Pro-oncogenic Role of Cathepsin B in Triple-Negative Breast Cancer Cells

Directory of Open Access Journals (Sweden)

Kyung-Min Yang

2017-12-01

Full Text Available Summary: Triple-negative breast cancer (TNBC is considered incurable with currently available treatments, highlighting the need for therapeutic targets and predictive biomarkers. Here, we report a unique role for Bcl-2-associated athanogene 2 (BAG2, which is significantly overexpressed in TNBC, in regulating the dual functions of cathepsin B as either a pro- or anti-oncogenic enzyme. Silencing BAG2 suppresses tumorigenesis and lung metastasis and induces apoptosis by increasing the intracellular mature form of cathepsin B, whereas BAG2 expression induces metastasis by blocking the auto-cleavage processing of pro-cathepsin B via interaction with the propeptide region. BAG2 regulates pro-cathepsin B/annexin II complex formation and facilitates the trafficking of pro-cathespin-B-containing TGN38-positive vesicles toward the cell periphery, leading to the secretion of pro-cathepsin B, which induces metastasis. Collectively, our results uncover BAG2 as a regulator of the oncogenic function of pro-cathepsin B and a potential diagnostic and therapeutic target that may reduce the burden of metastatic breast cancer. : The mechanisms controlling the pro- and anti-oncogenic roles of cathepsin B are unclear. Yang et al. find that BAG2 is a regulator of the dual functions of its client protein, CTSB, facilitating the progression of TNBC. Keywords: BAG2, cathepsin B, TNBC, tumorigenesis, metastasis, breast cancer, TGN38

The 5T mouse multiple myeloma model: Absence of c-myc oncogene rearrangement in early transplant generations

NARCIS (Netherlands)

Radl, J.; Punt, Y.A.; Enden-Vieveen, M.H.M. van den; Bentvelzen, P.A.J.; Bakkus, M.H.C.; Akker T., W. van den; Benner, R.

1990-01-01

Consistent chromosomal translocations involving the c-myc cellular oncogene and one of the three immunoglobulin loci are typical for human Burkitt's lymphoma, induced mouse plasmacytoma (MPC) and spontaneously arising rat immunocytoma (RIC). Another plasma cell malignancy, multiple myeloma (MM),

Hepatitis C virus core protein regulates p300/CBP co-activation function. Possible role in the regulation of NF-AT1 transcriptional activity

International Nuclear Information System (INIS)

Gomez-Gonzalo, Marta; Benedicto, Ignacio; Carretero, Marta; Lara-Pezzi, Enrique; Maldonado-Rodriguez, Alejandra; Moreno-Otero, Ricardo; Lai, Michael M.C.; Lopez-Cabrera, Manuel

2004-01-01

Hepatitis C virus (HCV) core is a viral structural protein; it also participates in some cellular processes, including transcriptional regulation. However, the mechanisms of core-mediated transcriptional regulation remain poorly understood. Oncogenic virus proteins often target p300/CBP, a known co-activator of a wide variety of transcription factors, to regulate the expression of cellular and viral genes. Here we demonstrate, for the first time, that HCV core protein interacts with p300/CBP and enhances both its acetyl-transferase and transcriptional activities. In addition, we demonstrate that nuclear core protein activates the NH 2 -terminal transcription activation domain (TAD) of NF-AT1 in a p300/CBP-dependent manner. We propose a model in which core protein regulates the co-activation function of p300/CBP and activates NF-AT1, and probably other p300/CBP-regulated transcription factors, by a novel mechanism involving the regulation of the acetylation state of histones and/or components of the transcriptional machinery

Plac8 Links Oncogenic Mutations to Regulation of Autophagy and Is Critical to Pancreatic Cancer Progression

Directory of Open Access Journals (Sweden)

Conan Kinsey

2014-05-01

Full Text Available Mutations in p53 and RAS potently cooperate in oncogenic transformation, and correspondingly, these genetic alterations frequently coexist in pancreatic ductal adenocarcinoma (PDA and other human cancers. Previously, we identified a set of genes synergistically activated by combined RAS and p53 mutations as frequent downstream mediators of tumorigenesis. Here, we show that the synergistically activated gene Plac8 is critical for pancreatic cancer growth. Silencing of Plac8 in cell lines suppresses tumor formation by blocking autophagy, a process essential for maintaining metabolic homeostasis in PDA, and genetic inactivation in an engineered mouse model inhibits PDA progression. We show that Plac8 is a critical regulator of the autophagic machinery, localizing to the lysosomal compartment and facilitating lysosome-autophagosome fusion. Plac8 thus provides a mechanistic link between primary oncogenic mutations and the induction of autophagy, a central mechanism of metabolic reprogramming, during PDA progression.

A Poly-ADP-Ribose Trigger Releases the Auto-Inhibition of a Chromatin Remodeling Oncogene.

Science.gov (United States)

Singh, Hari R; Nardozza, Aurelio P; Möller, Ingvar R; Knobloch, Gunnar; Kistemaker, Hans A V; Hassler, Markus; Harrer, Nadine; Blessing, Charlotte; Eustermann, Sebastian; Kotthoff, Christiane; Huet, Sébastien; Mueller-Planitz, Felix; Filippov, Dmitri V; Timinszky, Gyula; Rand, Kasper D; Ladurner, Andreas G

2017-12-07

DNA damage triggers chromatin remodeling by mechanisms that are poorly understood. The oncogene and chromatin remodeler ALC1/CHD1L massively decompacts chromatin in vivo yet is inactive prior to DNA-damage-mediated PARP1 induction. We show that the interaction of the ALC1 macrodomain with the ATPase module mediates auto-inhibition. PARP1 activation suppresses this inhibitory interaction. Crucially, release from auto-inhibition requires a poly-ADP-ribose (PAR) binding macrodomain. We identify tri-ADP-ribose as a potent PAR-mimic and synthetic allosteric effector that abrogates ATPase-macrodomain interactions, promotes an ungated conformation, and activates the remodeler's ATPase. ALC1 fragments lacking the regulatory macrodomain relax chromatin in vivo without requiring PARP1 activation. Further, the ATPase restricts the macrodomain's interaction with PARP1 under non-DNA damage conditions. Somatic cancer mutants disrupt ALC1's auto-inhibition and activate chromatin remodeling. Our data show that the NAD + -metabolite and nucleic acid PAR triggers ALC1 to drive chromatin relaxation. Modular allostery in this oncogene tightly controls its robust, DNA-damage-dependent activation. Copyright © 2017 Elsevier Inc. All rights reserved.

Interaction of x-rays and food pyrolysis products in producing oncogenic transformation in vitro

International Nuclear Information System (INIS)

Borek, C.; Ong, A.

1981-01-01

In recent years it has become evident from epidemiological and experimental data that a large number of environmental factors, including diet, play a role in modifying the incidence of cancer. Cell culture systems in which oncogenic transformation serves as an end point are powerful tools for evaluating these questions. Using such systems it has been shown recently that pyrolysis products from charred surfaces of broiled meat and fish can transform hamster embryo cells in vitro as well as produce tumors in the animal. Our studies in vitro have demonstrated the oncogenic potential of ionizing radiation in both hamster and human cells and have established in hamster cells the dose response relationship at doses ranging from 1 to 600 rad for x-rays and 0.1 to 150 rad for neutrons. The present work was aimed at evaluating whether there exists a cocarcinogenic interaction between a pyrolysis product and x-rays in their ability to transform hamster embryo cells in vitro. We have found that when cells are exposed to x-rays prior to treatment with the pyrolysis product there appears to be a synergistic interaction between the two agents in their ability to transform the cells

Utilizing ras signaling pathway to direct selective replication of herpes simplex virus-1.

Directory of Open Access Journals (Sweden)

Weihong Pan

Full Text Available Re-engineering the tropism of viruses is an attractive translational strategy for targeting cancer cells. The Ras signal transduction pathway is a central hub for a variety of pro-oncogenic events with a fundamental role in normal and neoplastic physiology. In this work we were interested in linking Ras activation to HSV-1 replication in a direct manner in order to generate a novel oncolytic herpes virus which can target cancer cells. To establish such link, we developed a mutant HSV-1 in which the expression of ICP4 (infected cell protein-4, a viral protein necessary for replication is controlled by activation of ELK, a transcription factor down-stream of the Ras pathway and mainly activated by ERK (extracellular signal-regulated kinase, an important Ras effector pathway. This mutant HSV-1 was named as Signal-Smart 1 (SS1. A series of prostate cells were infected with the SS1 virus. Cells with elevated levels of ELK activation were preferentially infected by the SS1 virus, as demonstrated by increased levels of viral progeny, herpetic glycoprotein C and overall SS1 viral protein production. Upon exposure to SS1, the proliferation, invasiveness and colony formation capabilities of prostate cancer cells with increased ELK activation were significantly decreased (p<0.05, while the rate of apoptosis/necrosis in these cells was increased. Additionally, high Ras signaling cells infected with SS1 showed a prominent arrest in the G1 phase of the cell cycle as compared to cells exposed to parental HSV-1. The results of this study reveal the potential for re-modeling the host-herpes interaction to specifically interfere with the life of cancer cells with increased Ras signaling. SS1 also serves as a "prototype" for development of a family of signal-smart viruses which can target cancer cells on the basis of their signaling portfolio.

Pervasive transcription read-through promotes aberrant expression of oncogenes and RNA chimeras in renal carcinoma

Science.gov (United States)

Grosso, Ana R; Leite, Ana P; Carvalho, Sílvia; Matos, Mafalda R; Martins, Filipa B; Vítor, Alexandra C; Desterro, Joana MP; Carmo-Fonseca, Maria; de Almeida, Sérgio F

2015-01-01

Aberrant expression of cancer genes and non-canonical RNA species is a hallmark of cancer. However, the mechanisms driving such atypical gene expression programs are incompletely understood. Here, our transcriptional profiling of a cohort of 50 primary clear cell renal cell carcinoma (ccRCC) samples from The Cancer Genome Atlas (TCGA) reveals that transcription read-through beyond the termination site is a source of transcriptome diversity in cancer cells. Amongst the genes most frequently mutated in ccRCC, we identified SETD2 inactivation as a potent enhancer of transcription read-through. We further show that invasion of neighbouring genes and generation of RNA chimeras are functional outcomes of transcription read-through. We identified the BCL2 oncogene as one of such invaded genes and detected a novel chimera, the CTSC-RAB38, in 20% of ccRCC samples. Collectively, our data highlight a novel link between transcription read-through and aberrant expression of oncogenes and chimeric transcripts that is prevalent in cancer. DOI: http://dx.doi.org/10.7554/eLife.09214.001 PMID:26575290

Malignant transformation of diploid human fibroblasts by transfection of oncogenes. Part 2, Progress report, July 1989--June 1992

Energy Technology Data Exchange (ETDEWEB)

McCormick, J.J.

1992-12-31

This document consist of brief reports prepared by postdoctoral students supported by the project, each describing his accomplishments under the grant. Topics include (1) Malignant Transformation of MSU-1. 1 Cells by Gamma Radiation, (2) Correlation between Levels of ras Expression and Presence of Transformed Phenotypes Including Tumorigenicity, Using a Modulatable Promoter, (3) Relation between Specific rad Oncogene Expression, (4) Correlation of Genetic Changes in Fibroblastic Tumors with Malignancies, (5)Transformation of MSU-1.1 Cells by sis Oncogene, (6) Malignant Transformation of MSU-1.0 Cells, (7) Correlation of Urokinase Plasminogen Activation (mu-PA) with Malignant Phenotype, (8)Two Dimensional Gel Electrophoresis Studies of the Proteins of the Major Cell Strains of the MSU-1 Family of Cells, and (9) Correlation between Proteinase Activity Levels and Malignancy.

Vav3 oncogene activates estrogen receptor and its overexpression may be involved in human breast cancer

International Nuclear Information System (INIS)

Lee, Kiwon; Liu, Yin; Mo, Jun Qin; Zhang, Jinsong; Dong, Zhongyun; Lu, Shan

2008-01-01

Our previous study revealed that Vav3 oncogene is overexpressed in human prostate cancer, activates androgen receptor, and stimulates growth in prostate cancer cells. The current study is to determine a potential role of Vav3 oncogene in human breast cancer and impact on estrogen receptor a (ERα)-mediated signaling axis. Immunohistochemistry analysis was performed in 43 breast cancer specimens and western blot analysis was used for human breast cancer cell lines to determine the expression level of Vav3 protein. The impact of Vav3 on breast cancer cell growth was determined by siRNA knockdown of Vav3 expression. The role of Vav3 in ERα activation was examined in luciferase reporter assays. Deletion mutation analysis of Vav3 protein was performed to localize the functional domain involved in ERα activation. Finally, the interaction of Vav3 and ERα was assessed by GST pull-down analysis. We found that Vav3 was overexpressed in 81% of human breast cancer specimens, particularly in poorly differentiated lesions. Vav3 activated ERα partially via PI3K-Akt signaling and stimulated growth of breast cancer cells. Vav3 also potentiated EGF activity for cell growth and ERα activation in breast cancer cells. More interestingly, we found that Vav3 complexed with ERα. Consistent with its function for AR, the DH domain of Vav3 was essential for ERα activation. Vav3 oncogene is overexpressed in human breast cancer. Vav3 complexes with ERα and enhances ERα activity. These findings suggest that Vav3 overexpression may aberrantly enhance ERα-mediated signaling axis and play a role in breast cancer development and/or progression

3D view to tumor suppression: Lkb1, polarity and the arrest of oncogenic c-Myc.

Science.gov (United States)

Partanen, Johanna I; Nieminen, Anni I; Klefstrom, Juha

2009-03-01

Machiavelli wrote, in his famous political treatise Il Principe, about disrupting organization by planting seeds of dissension or by eliminating necessary support elements. Tumor cells do exactly that by disrupting the organized architecture of epithelial cell layers during progression from contained benign tumor to full-blown invasive cancer. However, it is still unclear whether tumor cells primarily break free by activating oncogenes powerful enough to cause chaos or by eliminating tumor suppressor genes guarding the order of the epithelial organization. Studies in Drosophila have exposed genes that encode key regulators of the epithelial apicobasal polarity and which, upon inactivation, cause disorganization of the epithelial layers and promote unscheduled cell proliferation. These polarity regulator/tumor suppressor proteins, which include products of neoplastic tumor suppressor genes (nTSGs), are carefully positioned in polarized epithelial cells to maintain the order of epithelial structures and to impose a restraint on cell proliferation. In this review, we have explored the presence and prevalence of somatic mutations in the human counterparts of Drosophila polarity regulator/tumor suppressor genes across the human cancers. The screen points out LKB1, which is a causal genetic lesion in Peutz-Jeghers cancer syndrome, a gene mutated in certain sporadic cancers and a human homologue of the fly polarity gene par-4. We review the evidence linking Lkb1 protein to polarity regulation in the scope of our recent results suggesting a coupled role for Lkb1 as an architect of organized acinar structures and a suppressor of oncogenic c-Myc. We finally present models to explain how Lkb1-dependent formation of epithelial architecture is coupled to suppression of normal and oncogene-induced proliferation.

Analysis of nucleo-cytoplasmic shuttling of the proto-oncogene SET/I2PP2A

NARCIS (Netherlands)

Lam, B. Daniel; Anthony, Eloise C.; Hordijk, Peter L.

2012-01-01

SET/I2PP2A is a nuclear protein that was initially identified as an oncogene in human undifferentiated acute myeloid leukemia, fused to the nuclear porin Nup-214. In addition, SET is a potent inhibitior of the phosphatase PP2A. Previously, we proposed a model in which the small GTPase Rac1 recruits

An integrative approach unveils FOSL1 as an oncogene vulnerability in KRAS-driven lung and pancreatic cancer

DEFF Research Database (Denmark)

Vallejo, Adrian; Perurena, Naiara; Guruceaga, Elisabet

2017-01-01

KRAS mutated tumours represent a large fraction of human cancers, but the vast majority remains refractory to current clinical therapies. Thus, a deeper understanding of the molecular mechanisms triggered by KRAS oncogene may yield alternative therapeutic strategies. Here we report the identifica...

Arsenic trioxide inhibits cell proliferation and human papillomavirus oncogene expression in cervical cancer cells

International Nuclear Information System (INIS)

Wang, Hongtao; Gao, Peng; Zheng, Jie

2014-01-01

Highlights: • As 2 O 3 inhibits growth of cervical cancer cells and expression of HPV oncogenes in these cells. • HPV-negative cervical cancer cells are more sensitive to As 2 O 3 than HPV-positive cervical cancer cells. • HPV-18 positive cervical cancer cells are more sensitive to As 2 O 3 than HPV-16 positive cancer cells. • Down-regulation of HPV oncogenes by As 2 O 3 is partially due to the diminished AP-1 binding. - Abstract: Arsenic trioxide (As 2 O 3 ) has shown therapeutic effects in some leukemias and solid cancers. However, the molecular mechanisms of its anticancer efficacy have not been clearly elucidated, particularly in solid cancers. Our previous data showed that As 2 O 3 induced apoptosis of human papillomavirus (HPV) 16 DNA-immortalized human cervical epithelial cells and cervical cancer cells and inhibited the expression of HPV oncogenes in these cells. In the present study, we systemically examined the effects of As 2 O 3 on five human cervical cancer cell lines and explored the possible molecular mechanisms. MTT assay showed that HPV-negative C33A cells were more sensitive to growth inhibition induced by As 2 O 3 than HPV-positive cervical cancer cells, and HPV 18-positive HeLa and C4-I cells were more sensitive to As 2 O 3 than HPV 16-positive CaSki and SiHa cells. After As 2 O 3 treatment, both mRNA and protein levels of HPV E6 and E7 obviously decreased in all HPV positive cell lines. In contrast, p53 and Rb protein levels increased in all tested cell lines. Transcription factor AP-1 protein expression decreased significantly in HeLa, CaSki and C33A cells with ELISA method. These results suggest that As 2 O 3 is a potential anticancer drug for cervical cancer

Resting potential, oncogene-induced tumorigenesis, and metastasis: the bioelectric basis of cancer in vivo

Science.gov (United States)

Lobikin, Maria; Chernet, Brook; Lobo, Daniel; Levin, Michael

2012-12-01

Cancer may result from localized failure of instructive cues that normally orchestrate cell behaviors toward the patterning needs of the organism. Steady-state gradients of transmembrane voltage (Vmem) in non-neural cells are instructive, epigenetic signals that regulate pattern formation during embryogenesis and morphostatic repair. Here, we review molecular data on the role of bioelectric cues in cancer and present new findings in the Xenopus laevis model on how the microenvironment's biophysical properties contribute to cancer in vivo. First, we investigated the melanoma-like phenotype arising from serotonergic signaling by ‘instructor’ cells—a cell population that is able to induce a metastatic phenotype in normal melanocytes. We show that when these instructor cells are depolarized, blood vessel patterning is disrupted in addition to the metastatic phenotype induced in melanocytes. Surprisingly, very few instructor cells need to be depolarized for the hyperpigmentation phenotype to occur; we present a model of antagonistic signaling by serotonin receptors that explains the unusual all-or-none nature of this effect. In addition to the body-wide depolarization-induced metastatic phenotype, we investigated the bioelectrical properties of tumor-like structures induced by canonical oncogenes and cancer-causing compounds. Exposure to carcinogen 4-nitroquinoline 1-oxide (4NQO) induces localized tumors, but has a broad (and variable) effect on the bioelectric properties of the whole body. Tumors induced by oncogenes show aberrantly high sodium content, representing a non-invasive diagnostic modality. Importantly, depolarized transmembrane potential is not only a marker of cancer but is functionally instructive: susceptibility to oncogene-induced tumorigenesis is significantly reduced by forced prior expression of hyperpolarizing ion channels. Importantly, the same effect can be achieved by pharmacological manipulation of endogenous chloride channels, suggesting

Arsenic trioxide inhibits cell proliferation and human papillomavirus oncogene expression in cervical cancer cells

Energy Technology Data Exchange (ETDEWEB)

Wang, Hongtao [Department of Pathology, School of Medicine, Southeast University, Nanjing 210009 (China); Gao, Peng [Department of Internal Medicine, University of Iowa, Iowa City, IA 52242 (United States); Zheng, Jie, E-mail: jiezheng54@126.com [Department of Pathology, School of Medicine, Southeast University, Nanjing 210009 (China)

2014-09-05

Highlights: • As{sub 2}O{sub 3} inhibits growth of cervical cancer cells and expression of HPV oncogenes in these cells. • HPV-negative cervical cancer cells are more sensitive to As{sub 2}O{sub 3} than HPV-positive cervical cancer cells. • HPV-18 positive cervical cancer cells are more sensitive to As{sub 2}O{sub 3} than HPV-16 positive cancer cells. • Down-regulation of HPV oncogenes by As{sub 2}O{sub 3} is partially due to the diminished AP-1 binding. - Abstract: Arsenic trioxide (As{sub 2}O{sub 3}) has shown therapeutic effects in some leukemias and solid cancers. However, the molecular mechanisms of its anticancer efficacy have not been clearly elucidated, particularly in solid cancers. Our previous data showed that As{sub 2}O{sub 3} induced apoptosis of human papillomavirus (HPV) 16 DNA-immortalized human cervical epithelial cells and cervical cancer cells and inhibited the expression of HPV oncogenes in these cells. In the present study, we systemically examined the effects of As{sub 2}O{sub 3} on five human cervical cancer cell lines and explored the possible molecular mechanisms. MTT assay showed that HPV-negative C33A cells were more sensitive to growth inhibition induced by As{sub 2}O{sub 3} than HPV-positive cervical cancer cells, and HPV 18-positive HeLa and C4-I cells were more sensitive to As{sub 2}O{sub 3} than HPV 16-positive CaSki and SiHa cells. After As{sub 2}O{sub 3} treatment, both mRNA and protein levels of HPV E6 and E7 obviously decreased in all HPV positive cell lines. In contrast, p53 and Rb protein levels increased in all tested cell lines. Transcription factor AP-1 protein expression decreased significantly in HeLa, CaSki and C33A cells with ELISA method. These results suggest that As{sub 2}O{sub 3} is a potential anticancer drug for cervical cancer.

NF-κB-Activating Complex Engaged in Response to EGFR Oncogene Inhibition Drives Tumor Cell Survival and Residual Disease in Lung Cancer

Directory of Open Access Journals (Sweden)

Collin M. Blakely

2015-04-01

Full Text Available Although oncogene-targeted therapy often elicits profound initial tumor responses in patients, responses are generally incomplete because some tumor cells survive initial therapy as residual disease that enables eventual acquired resistance. The mechanisms underlying tumor cell adaptation and survival during initial therapy are incompletely understood. Here, through the study of EGFR mutant lung adenocarcinoma, we show that NF-κB signaling is rapidly engaged upon initial EGFR inhibitor treatment to promote tumor cell survival and residual disease. EGFR oncogene inhibition induced an EGFR-TRAF2-RIP1-IKK complex that stimulated an NF-κB-mediated transcriptional survival program. The direct NF-κB inhibitor PBS-1086 suppressed this adaptive survival program and increased the magnitude and duration of initial EGFR inhibitor response in multiple NSCLC models, including a patient-derived xenograft. These findings unveil NF-κB activation as a critical adaptive survival mechanism engaged by EGFR oncogene inhibition and provide rationale for EGFR and NF-κB co-inhibition to eliminate residual disease and enhance patient responses.

Epithelial–mesenchymal transition during oncogenic transformation induced by hexavalent chromium involves reactive oxygen species-dependent mechanism in lung epithelial cells

Energy Technology Data Exchange (ETDEWEB)

Ding, Song-Ze, E-mail: dingsongze@hotmail.com [Department of Internal Medicine, Henan Provincial People’s Hospital, Zhengzhou University, Wei-Wu Road, Zhengzhou, Henan 450000 (China); Graduate Center for Toxicology, College of Medicine, University of Kentucky, Lexington, KY 40536 (United States); Yang, Yu-Xiu; Li, Xiu-Ling [Department of Internal Medicine, Henan Provincial People’s Hospital, Zhengzhou University, Wei-Wu Road, Zhengzhou, Henan 450000 (China); Michelli-Rivera, Audrey [Graduate Center for Toxicology, College of Medicine, University of Kentucky, Lexington, KY 40536 (United States); Han, Shuang-Yin [Department of Internal Medicine, Henan Provincial People’s Hospital, Zhengzhou University, Wei-Wu Road, Zhengzhou, Henan 450000 (China); Wang, Lei; Pratheeshkumar, Poyil; Wang, Xin; Lu, Jian; Yin, Yuan-Qin; Budhraja, Amit; Hitron, Andrew J. [Graduate Center for Toxicology, College of Medicine, University of Kentucky, Lexington, KY 40536 (United States)

2013-05-15

Hexavalent chromium [Cr(VI)] is an important human carcinogen associated with pulmonary diseases and lung cancer. Exposure to Cr(VI) induces DNA damage, cell morphological change and malignant transformation in human lung epithelial cells. Despite extensive studies, the molecular mechanisms remain elusive, it is also not known if Cr(VI)-induced transformation might accompany with invasive properties to facilitate metastasis. We aimed to study Cr(VI)-induced epithelial–mesenchymal transition (EMT) and invasion during oncogenic transformation in lung epithelial cells. The results showed that Cr(VI) at low doses represses E-cadherin mRNA and protein expression, enhances mesenchymal marker vimentin expression and transforms the epithelial cell into fibroblastoid morphology. Cr(VI) also increases cell invasion and promotes colony formation. Further studies indicated that Cr(VI) uses multiple mechanisms to repress E-cadherin expression, including activation of E-cadherin repressors such as Slug, ZEB1, KLF8 and enhancement the binding of HDAC1 in E-cadherin gene promoter, but DNA methylation is not responsible for the loss of E-cadherin. Catalase reduces Cr(VI)-induced E-cadherin and vimentin protein expression, attenuates cell invasion in matrigel and colony formation on soft agar. These results demonstrate that exposure to a common human carcinogen, Cr(VI), induces EMT and invasion during oncogenic transformation in lung epithelial cells and implicate in cancer metastasis and prevention. - Graphical abstract: Epithelial–mesenchymal transition during oncogenic transformation induced by hexavalent chromium involves reactive oxygen species-dependent mechanisms in lung epithelial cells. - Highlights: • We study if Cr(VI) might induce EMT and invasion in epithelial cells. • Cr(VI) induces EMT by altering E-cadherin and vimentin expression. • It also increases cell invasion and promotes oncogenic transformation. • Catalase reduces Cr(VI)-induced EMT, invasion and

Combined drug action of 2-phenylimidazo[2,1-b]benzothiazole derivatives on cancer cells according to their oncogenic molecular signatures.

Directory of Open Access Journals (Sweden)

Alessandro Furlan

Full Text Available The development of targeted molecular therapies has provided remarkable advances into the treatment of human cancers. However, in most tumors the selective pressure triggered by anticancer agents encourages cancer cells to acquire resistance mechanisms. The generation of new rationally designed targeting agents acting on the oncogenic path(s at multiple levels is a promising approach for molecular therapies. 2-phenylimidazo[2,1-b]benzothiazole derivatives have been highlighted for their properties of targeting oncogenic Met receptor tyrosine kinase (RTK signaling. In this study, we evaluated the mechanism of action of one of the most active imidazo[2,1-b]benzothiazol-2-ylphenyl moiety-based agents, Triflorcas, on a panel of cancer cells with distinct features. We show that Triflorcas impairs in vitro and in vivo tumorigenesis of cancer cells carrying Met mutations. Moreover, Triflorcas hampers survival and anchorage-independent growth of cancer cells characterized by "RTK swapping" by interfering with PDGFRβ phosphorylation. A restrained effect of Triflorcas on metabolic genes correlates with the absence of major side effects in vivo. Mechanistically, in addition to targeting Met, Triflorcas alters phosphorylation levels of the PI3K-Akt pathway, mediating oncogenic dependency to Met, in addition to Retinoblastoma and nucleophosmin/B23, resulting in altered cell cycle progression and mitotic failure. Our findings show how the unusual binding plasticity of the Met active site towards structurally different inhibitors can be exploited to generate drugs able to target Met oncogenic dependency at distinct levels. Moreover, the disease-oriented NCI Anticancer Drug Screen revealed that Triflorcas elicits a unique profile of growth inhibitory-responses on cancer cell lines, indicating a novel mechanism of drug action. The anti-tumor activity elicited by 2-phenylimidazo[2,1-b]benzothiazole derivatives through combined inhibition of distinct effectors in

Cell cycle deregulation by the HBx protein of hepatitis B virus

Directory of Open Access Journals (Sweden)

Vijay Kumar

2007-02-01

Full Text Available

Cell cycle control by oncogenic viruses usually involves disruption of the normal restraints on cellular proliferation via abnormal proteolytic degradation and malignant transformation of cells. The cell cycle regulatory molecules viz. cyclins, cyclin-dependent kinases (cdks and inhibitors of cdks as well as the transcriptional targets of signaling pathways induce cells to move through the cell cycle checkpoints. These check points are often found deregulated in tumor cells and in the cells afflicted with DNA tumor viruses predisposing them towards transformation. The X protein or HBx of hepatitis B virus is a promiscuous transactivator that has been implicated in the development of hepatocellular carcinoma in humans. However, the exact role of HBx in establishing a permissive environment for hepatocarcinogenesis is not fully understood. HBx activates the Ras-Raf-MAP kinase signaling cascade, through which it activates transcription factors AP-1 and NFkappa B, and stimulates cell DNA synthesis. HBx shows a profound effect on cell cycle progression even in the absence of serum. It can override the replicative senescence of cells in G0 phase by binding to p55sen. It stimulates the G0 cells to transit through G1 phase by activating Src kinases and the cyclin A-cyclin-dependent kinase 2 complexes, that in turn induces the cyclin A promoter. There is an early and sustained level of cyclin-cdk2 complex in the presence of HBx during the cell cycle which is coupled with an increased protein kinase activity of cdk2 suggesting an early appearance of S phase. The interaction between cyclin-cdk2 complex and HBx occurs through its carboxyterminal region (amino acids 85-119 and requires a constitutive Src kinase activity. The increased cdk2 activity is associated with stabilization of cyclin E as well as proteasomal degradation of cdk inhibitor p27Kip1. Notably, the HBx mutant

Activating mutation in MET oncogene in familial colorectal cancer

Directory of Open Access Journals (Sweden)

Schildkraut Joellen M

2011-10-01

Full Text Available Abstract Background In developed countries, the lifetime risk of developing colorectal cancer (CRC is 5%, and it is the second leading cause of death from cancer. The presence of family history is a well established risk factor with 25-35% of CRCs attributable to inherited and/or familial factors. The highly penetrant inherited colon cancer syndromes account for approximately 5%, leaving greater than 20% without clear genetic definition. Familial colorectal cancer has been linked to chromosome 7q31 by multiple affected relative pair studies. The MET proto-oncogene which resides in this chromosomal region is considered a candidate for genetic susceptibility. Methods MET exons were amplified by PCR from germline DNA of 148 affected sibling pairs with colorectal cancer. Amplicons with altered sequence were detected with high-resolution melt-curve analysis using a LightScanner (Idaho Technologies. Samples demonstrating alternative melt curves were sequenced. A TaqMan assay for the specific c.2975C >T change was used to confirm this mutation in a cohort of 299 colorectal cancer cases and to look for allelic amplification in tumors. Results Here we report a germline non-synonymous change in the MET proto-oncogene at amino acid position T992I (also reported as MET p.T1010I in 5.2% of a cohort of sibling pairs affected with CRC. This genetic variant was then confirmed in a second cohort of individuals diagnosed with CRC and having a first degree relative with CRC at prevalence of 4.1%. This mutation has been reported in cancer cells of multiple origins, including 2.5% of colon cancers, and in Conclusions Although the MET p.T992I genetic mutation is commonly found in somatic colorectal cancer tissues, this is the first report also implicating this MET genetic mutation as a germline inherited risk factor for familial colorectal cancer. Future studies on the cancer risks associated with this mutation and the prevalence in different at-risk populations will

Minor Capsid Protein L2 Polytope Induces Broad Protection against Oncogenic and Mucosal Human Papillomaviruses.

Science.gov (United States)

Pouyanfard, Somayeh; Spagnoli, Gloria; Bulli, Lorenzo; Balz, Kathrin; Yang, Fan; Odenwald, Caroline; Seitz, Hanna; Mariz, Filipe C; Bolchi, Angelo; Ottonello, Simone; Müller, Martin

2018-02-15

The amino terminus of the human papillomavirus (HPV) minor capsid protein L2 contains a major cross-neutralization epitope which provides the basis for the development of a broadly protecting HPV vaccine. A wide range of protection against different HPV types would eliminate one of the major drawbacks of the commercial, L1-based prophylactic vaccines. Previously, we have reported that insertion of the L2 epitope into a scaffold composed of bacterial thioredoxin protein generates a potent antigen inducing comprehensive protection against different animal and human papillomaviruses. We also reported, however, that although protection is broad, some oncogenic HPV types escape the neutralizing antibody response, if L2 epitopes from single HPV types are used as immunogen. We were able to compensate for this by applying a mix of thioredoxin proteins carrying L2 epitopes from HPV16, -31, and -51. As the development of a cost-efficient HPV prophylactic vaccines is one of our objectives, this approach is not feasible as it requires the development of multiple good manufacturing production processes in combination with a complex vaccine formulation. Here, we report the development of a thermostable thioredoxin-based single-peptide vaccine carrying an L2 polytope of up to 11 different HPV types. The L2 polytope antigens have excellent abilities in respect to broadness of protection and robustness of induced immune responses. To further increase immunogenicity, we fused the thioredoxin L2 polytope antigen with a heptamerization domain. In the final vaccine design, we achieve protective responses against all 14 oncogenic HPV types that we have analyzed plus the low-risk HPVs 6 and 11 and a number of cutaneous HPVs. IMPORTANCE Infections by a large number of human papillomaviruses lead to malignant and nonmalignant disease. Current commercial vaccines based on virus-like particles (VLPs) effectively protect against some HPV types but fail to do so for most others. Further, only

Hepatitis C Virus-Related Lymphomagenesis in a Mouse Model

Science.gov (United States)

Tsukiyama-Kohara, Kyoko; Sekiguchi, Satoshi; Kasama, Yuri; Salem, Nagla Elwy; Machida, Keigo; Kohara, Michinori

2011-01-01

B cell non-Hodgkin lymphoma is a typical extrahepatic manifestation frequently associated with hepatitis C virus (HCV) infection. The mechanism by which HCV infection leads to lymphoproliferative disorder remains unclear. Our group established HCV transgenic mice that expressed the full HCV genome in B cells (RzCD19Cre mice). We observed a 25.0% incidence of diffuse large B cell non-Hodgkin lymphomas (22.2% in male and 29.6% in female mice) within 600 days of birth. Interestingly, RzCD19Cre mice with substantially elevated serum-soluble interleukin-2 receptor α-subunit (sIL-2Rα) levels (>1000 pg/mL) developed B cell lymphomas. Another mouse model of lymphoproliferative disorder was established by persistent expression of HCV structural proteins through disruption of interferon regulatory factor-1 (irf-1_/_/CN2 mice). Irf-1_/_/CN2 mice showed extremely high incidences of lymphomas and lymphoproliferative disorders. Moreover, these mice showed increased levels of interleukin (IL)-2, IL-10, and Bcl-2 as well as increased Bcl-2 expression, which promoted oncogenic transformation of lymphocytes. PMID:22084693

[Human papilloma virus and its association with oral cancer].

Science.gov (United States)

Bologna-Molina, Ronell E; Castañeda-Castaneira, Raúl E; Molina-Frechero, Nelly; Pérez-Rodríguez, Eréndira

2006-01-01

Oral cancer it a pathology of multifactorial etiology, where some factors such as age, sex, race, genetic predisposition, nutrition, and the use of tobacco and alcohol have a bearing on. In the last years, some authors showed the implication of the human papilloma virus (HPV) in the development of precarcinogenic lesions and of oral squamous cell carcinoma. The infection by HPV has been associated to hyperplastic epithelial lesions, papilloma and warty carcinoma in skin and in different types of mucosa, including the anus-genital, cervical, urethral, tracheobronchial, nasal, laryngeal and oral mucosa tracts. The viral high-risk geno-types (oncogenic) such as 16, 18, 31, 33 and 35 are frequently associated to leukoplakia and squamous carcinoma. An association of HPV with oral squamous carcinoma in patients that consume tobacco and alcohol has been fundamentally established. It is important to study and to frequently review the role that viral infections and cancer have, and maybe in the future, it would be possible to create a vaccine that diminishes the frequency of oncological problems.

Bleomycin Can Cleave an Oncogenic Noncoding RNA.

Science.gov (United States)

Angelbello, Alicia J; Disney, Matthew D

2018-01-04

Noncoding RNAs are pervasive in cells and contribute to diseases such as cancer. A question in biomedical research is whether noncoding RNAs are targets of medicines. Bleomycin is a natural product that cleaves DNA; however, it is known to cleave RNA in vitro. Herein, an in-depth analysis of the RNA cleavage preferences of bleomycin A5 is presented. Bleomycin A5 prefers to cleave RNAs with stretches of AU base pairs. Based on these preferences and bioinformatic analysis, the microRNA-10b hairpin precursor was identified as a potential substrate for bleomycin A5. Both in vitro and cellular experiments demonstrated cleavage. Importantly, chemical cleavage by bleomycin A5 in the microRNA-10b hairpin precursors occurred near the Drosha and Dicer enzymatic processing sites and led to destruction of the microRNA. Evidently, oncogenic noncoding RNAs can be considered targets of cancer medicines and might elicit their pharmacological effects by targeting noncoding RNA. © 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

The structural pathway of interleukin 1 (IL-1 initiated signaling reveals mechanisms of oncogenic mutations and SNPs in inflammation and cancer.

Directory of Open Access Journals (Sweden)

Saliha Ece Acuner Ozbabacan

2014-02-01

Full Text Available Interleukin-1 (IL-1 is a large cytokine family closely related to innate immunity and inflammation. IL-1 proteins are key players in signaling pathways such as apoptosis, TLR, MAPK, NLR and NF-κB. The IL-1 pathway is also associated with cancer, and chronic inflammation increases the risk of tumor development via oncogenic mutations. Here we illustrate that the structures of interfaces between proteins in this pathway bearing the mutations may reveal how. Proteins are frequently regulated via their interactions, which can turn them ON or OFF. We show that oncogenic mutations are significantly at or adjoining interface regions, and can abolish (or enhance the protein-protein interaction, making the protein constitutively active (or inactive, if it is a repressor. We combine known structures of protein-protein complexes and those that we have predicted for the IL-1 pathway, and integrate them with literature information. In the reconstructed pathway there are 104 interactions between proteins whose three dimensional structures are experimentally identified; only 15 have experimentally-determined structures of the interacting complexes. By predicting the protein-protein complexes throughout the pathway via the PRISM algorithm, the structural coverage increases from 15% to 71%. In silico mutagenesis and comparison of the predicted binding energies reveal the mechanisms of how oncogenic and single nucleotide polymorphism (SNP mutations can abrogate the interactions or increase the binding affinity of the mutant to the native partner. Computational mapping of mutations on the interface of the predicted complexes may constitute a powerful strategy to explain the mechanisms of activation/inhibition. It can also help explain how an oncogenic mutation or SNP works.

Mutations within ICP4 acquired during in vitro attenuation do not alter virulence of recombinant Marek's disease viruses in vivo

Directory of Open Access Journals (Sweden)

Evin Hildebrandt

2015-12-01

Full Text Available Marek's disease (MD is a T-cell lymphoma of chickens caused by the oncogenic Marek's disease virus (MDV. MD is primarily controlled by live-attenuated vaccines generated by repeated in vitro serial passage. Previous efforts to characterize attenuated MDVs identified numerous mutations, particularly a convergence of high-frequency mutations around amino acids 60–63 within ICP4 (RS1, therefore, ICP4 was considered a candidate gene deserving further characterization. Recombinant MDVs were generated containing a single Q63H mutation or double Q63H + S1630P mutations. Despite the repetitive nature of mutations within ICP4, neither recombinant virus decreased virulence, although one mutant reduced in vivo replication and failed to transmit horizontally. Our results indicate that these mutations are insufficient to reduce disease incidence in infected birds, and suggest that variants in ICP4 do not directly alter virulence, but rather may enhance MDV replication rates in vitro, offering an explanation for the widespread occurrence of ICP4 mutations in a variety of attenuated herpesviruses.

Host genetics of Epstein-Barr virus infection, latency and disease.

Science.gov (United States)

Houldcroft, Charlotte J; Kellam, Paul

2015-03-01

Epstein-Barr virus (EBV) infects 95% of the adult population and is the cause of infectious mononucleosis. It is also associated with 1% of cancers worldwide, such as nasopharyngeal carcinoma, Hodgkin's lymphoma and Burkitt's lymphoma. Human and cancer genetic studies are now major forces determining gene variants associated with many cancers, including nasopharyngeal carcinoma and Hodgkin's lymphoma. Host genetics is also important in infectious disease; however, there have been no large-scale efforts towards understanding the contribution that human genetic variation plays in primary EBV infection and latency. This review covers 25 years of studies into host genetic susceptibility to EBV infection and disease, from candidate gene studies, to the first genome-wide association study of EBV antibody response, and an EBV-status stratified genome-wide association study of Hodgkin's lymphoma. Although many genes are implicated in EBV-related disease, studies are often small, not replicated or followed up in a different disease. Larger, appropriately powered genomic studies to understand the host response to EBV will be needed to move our understanding of the biology of EBV infection beyond the handful of genes currently identified. Fifty years since the discovery of EBV and its identification as a human oncogenic virus, a glimpse of the future is shown by the first whole-genome and whole-exome studies, revealing new human genes at the heart of the host-EBV interaction. © 2014 The Authors Reviews in Medical Virology published by John Wiley & Sons Ltd.

Mutations of the KRAS oncogene in endometrial hyperplasia and carcinoma.

Directory of Open Access Journals (Sweden)

Wiesława Niklińska

2009-05-01

Full Text Available The aim of this study was to examine the prevalence and clinicopathological significance of KRAS point mutation in endometrial hyperplasia and carcinoma. We analysed KRAS in 11 cases of complex atypical hyperplasia and in 49 endometrial carcinomas using polymerase chain reaction associated with restriction fragment length polymorphism (PCR-RFPL. Point mutations at codon 12 of KRAS oncogene were identified in 7 of 49 (14,3% tumor specimens and in 2 of 11 (18,2% hyperplasias. No correlation was found between KRAS gene mutation and age at onset, histology, grade of differentiation and clinical stage. We conclude that KRAS mutation is a relatively common event in endometrial carcinogenesis, but with no prognostic value.

Is it possible to catch leukemia from a cat?

NARCIS (Netherlands)

Horzinek, M.C.; Nowotny, N.; Uthman, A.; Haas, O.A.; Borkhardt, A.; Lechner, K.; Egberink, H.F.; Mostl, K.

1995-01-01

The commentary of Donaldson and colleagues lists several of the unanswered questions concerning the potential oncogenicity of feline leukaemia virus (FeLV) and feline immunodeficiency virus (FIV) in human beings. As a contribution to this debate, we report a study in patients with

Systems biology modeling reveals a possible mechanism of the tumor cell death upon oncogene inactivation in EGFR addicted cancers.

Directory of Open Access Journals (Sweden)

Jian-Ping Zhou

Full Text Available Despite many evidences supporting the concept of "oncogene addiction" and many hypotheses rationalizing it, there is still a lack of detailed understanding to the precise molecular mechanism underlying oncogene addiction. In this account, we developed a mathematic model of epidermal growth factor receptor (EGFR associated signaling network, which involves EGFR-driving proliferation/pro-survival signaling pathways Ras/extracellular-signal-regulated kinase (ERK and phosphoinositol-3 kinase (PI3K/AKT, and pro-apoptotic signaling pathway apoptosis signal-regulating kinase 1 (ASK1/p38. In the setting of sustained EGFR activation, the simulation results show a persistent high level of proliferation/pro-survival effectors phospho-ERK and phospho-AKT, and a basal level of pro-apoptotic effector phospho-p38. The potential of p38 activation (apoptotic potential due to the elevated level of reactive oxygen species (ROS is largely suppressed by the negative crosstalk between PI3K/AKT and ASK1/p38 pathways. Upon acute EGFR inactivation, the survival signals decay rapidly, followed by a fast increase of the apoptotic signal due to the release of apoptotic potential. Overall, our systems biology modeling together with experimental validations reveals that inhibition of survival signals and concomitant release of apoptotic potential jointly contribute to the tumor cell death following the inhibition of addicted oncogene in EGFR addicted cancers.

An update: Epstein-Barr virus and immune evasion via microRNA regulation.

Science.gov (United States)

Zuo, Lielian; Yue, Wenxin; Du, Shujuan; Xin, Shuyu; Zhang, Jing; Liu, Lingzhi; Li, Guiyuan; Lu, Jianhong

2017-06-01

Epstein-Barr virus (EBV) is an oncogenic virus that ubiquitously establishes life-long persistence in humans. To ensure its survival and maintain its B cell transformation function, EBV has developed powerful strategies to evade host immune responses. Emerging evidence has shown that microRNAs (miRNAs) are powerful regulators of the maintenance of cellular homeostasis. In this review, we summarize current progress on how EBV utilizes miRNAs for immune evasion. EBV encodes miRNAs targeting both viral and host genes involved in the immune response. The miRNAs are found in two gene clusters, and recent studies have demonstrated that lack of these clusters increases the CD4 + and CD8 + T cell response of infected cells. These reports strongly indicate that EBV miRNAs are critical for immune evasion. In addition, EBV is able to dysregulate the expression of a variety of host miRNAs, which influence multiple immune-related molecules and signaling pathways. The transport via exosomes of EBV-regulated miRNAs and viral proteins contributes to the construction and modification of the inflammatory tumor microenvironment. During EBV immune evasion, viral proteins, immune cells, chemokines, pro-inflammatory cytokines, and pro-apoptosis molecules are involved. Our increasing knowledge of the role of miRNAs in immune evasion will improve the understanding of EBV persistence and help to develop new treatments for EBV-associated cancers and other diseases.

Anti-ATLA (antibody to adult T-cell leukemia-lymphoma virus-associated antigen)-negative adult T-cell leukemia-lymphoma.

Science.gov (United States)

Shimoyama, M; Minato, K; Tobinai, K; Nagai, M; Setoya, T; Watanabe, S; Hoshino, H; Miwa, M; Nagoshi, H; Ichiki, N; Fukushima, N; Sugiura, K; Funaki, N

1983-01-01

Five cases of adult T-cell leukemia-lymphoma (ATL) having typical clinicohematologic and morphologic features but negative for anti-ATLA [antibody to ATL virus (ATLV)-associated antigen (ATLA)] are presented. Some differences in immunologic, epidemiologic, and serologic data between anti-ATLA-positive and -negative ATLs are also described. Expression of ATLA in early primary cultured leukemic cells was found to be negative in three patients tested (Cases 1, 2 and 4), however, a long-term cultured cell line, ATL-6A, derived from peripheral blood leukemia cells from Case 1, was found to express ATLA. Mother of Case 1 and a daughter of Case 2 were anti-ATLA negative. These results indicate that ATLV was involved in certain anti-ATLA-negative ATL patients, at least in Case 1, and that the patient had no detectable immune response against ATLV and ATLA. However, in other cases in which no ATLA reactivity of serum and no ATLA expression in cultured leukemic cells were observed, another possibility such as activation of an unknown cellular oncogene specific for ATL without ATLV involvement may be considered. In order to prove these possibilities definitely, it is necessary to elucidate whether or not proviral DNA of ATLV is integrated into chromosomal DNA of ATL cells and to find a cellular oncogene specific for ATL in the future.

Human papilloma virus (HPV) prophylactic vaccination: challenges for public health and implications for screening.

Science.gov (United States)

Adams, M; Jasani, B; Fiander, A

2007-04-20

Prophylactic vaccination against high risk human papilloma virus (HPV) 16 and 18 represents an exciting means of protection against HPV related malignancy. However, this strategy alone, even if there is a level of cross protection against other oncogenic viruses, cannot completely prevent cervical cancer. In some developed countries cervical screening programmes have reduced the incidence of invasive cervical cancer by up to 80% although this decline has now reached a plateau with current cancers occurring in patients who have failed to attend for screening or where the sensitivity of the tests have proved inadequate. Cervical screening is inevitably associated with significant anxiety for the many women who require investigation and treatment following abnormal cervical cytology. However, it is vitally important to stress the need for continued cervical screening to complement vaccination in order to optimise prevention in vaccinees and prevent cervical cancer in older women where the value of vaccination is currently unclear. It is likely that vaccination will ultimately change the natural history of HPV disease by reducing the influence of the highly oncogenic types HPV 16 and 18. In the long term this is likely to lead to an increase in recommended screening intervals. HPV vaccination may also reduce the positive predictive value of cervical cytology by reducing the number of truly positive abnormal smears. Careful consideration is required to ensure vaccination occurs at an age when the vaccine is most effective immunologically and when uptake is likely to be high. Antibody titres following vaccination in girls 12-16 years have been shown to be significantly higher than in older women, favouring vaccination in early adolescence prior contact with the virus. Highest prevalence rates for HPV infection are seen following the onset of sexual activity and therefore vaccination would need to be given prior to sexual debut. Since 20% of adolescents are sexually

Effects of cellular non-protein sulfhydryl depletion in radiation induced oncogenic transformation and genotoxicity in mouse C3H 10T1/2 cells

International Nuclear Information System (INIS)

Hei, T.K.; Geard, C.R.; Hall, E.J.

1984-01-01

A study was made of the effects of cellular non-protein sulfhydryl (NPSH) depletion on cytotoxicity, cell cycle kinetics, oncogenic transformation and sister chromatid exchange (SCE) in C 3 H 10T1/2 cells. Using DL-Buthionine S-R-Sulfoximine (BSO) to deplete thiols, it was found spectrophotometrically that less than 5% of control NPSH level remained in the cells after 24-hour treatment under aerated conditions. Such NPSH depleted cells, when subject to a 3 Gy γ-ray treatment, were found to have no radiosensitizing response either in terms of cell survival or oncogenic transformation. In addition, decreased levels of NPSH had no effect on spontaneous or radiation-induced SCE nor were cell cycle kinetics additionally altered. Therefore, the inability of NPSH depletion to alter γ-ray induced cellular transformation was unrelated to any possible effect of BSO on the cell cycle. These results suggest that such depletion may result in little or no additional oncogenic or genotoxic effects on aerated normal tissues

Activation of the JNK pathway is essential for transformation by the Met oncogene.

Science.gov (United States)

Rodrigues, G A; Park, M; Schlessinger, J

1997-05-15

The Met/Hepatocyte Growth Factor (HGF) receptor tyrosine kinase is oncogenically activated through a rearrangement that creates a hybrid gene Tpr-Met. The resultant chimeric p65(Tpr-Met) protein is constitutively phosphorylated on tyrosine residues in vivo and associates with a number of SH2-containing signaling molecules including the p85 subunit of PI-3 kinase and the Grb2 adaptor protein, which couples receptor tyrosine kinases to the Ras signaling pathway. Mutation of the binding site for Grb2 impairs the ability of Tpr-Met oncoprotein to transform fibroblasts, suggesting that the activation of the Ras/MAP kinase signaling pathway through Grb2 may be essential for cellular transformation. To test this hypothesis dominant-negative mutants of Grb2 with deletions of the SH3 domains were introduced into Tpr-Met transformed fibroblasts. Cells overexpressing the mutants were found to be morphologically reverted and exhibited reduced growth in soft agar. Surprisingly, the Grb2 mutants blocked activation of the JNK/SAPK but not MAP kinase activity induced by the Tpr-Met oncoprotein. Additionally, cells expressing dominant-negative Grb2 mutants had reduced PI-3-kinase activity and dominant-negative mutants of Rac1 blocked both Tpr-Met-induced transformation and activation of JNK. These experiments reveal a novel link between Met and the JNK pathway, which is essential for transformation by this oncogene.

Genomic profiling identifies GATA6 as a candidate oncogene amplified in pancreatobiliary cancer.

Directory of Open Access Journals (Sweden)

Kevin A Kwei

2008-05-01

Full Text Available Pancreatobiliary cancers have among the highest mortality rates of any cancer type. Discovering the full spectrum of molecular genetic alterations may suggest new avenues for therapy. To catalogue genomic alterations, we carried out array-based genomic profiling of 31 exocrine pancreatic cancers and 6 distal bile duct cancers, expanded as xenografts to enrich the tumor cell fraction. We identified numerous focal DNA amplifications and deletions, including in 19% of pancreatobiliary cases gain at cytoband 18q11.2, a locus uncommonly amplified in other tumor types. The smallest shared amplification at 18q11.2 included GATA6, a transcriptional regulator previously linked to normal pancreas development. When amplified, GATA6 was overexpressed at both the mRNA and protein levels, and strong immunostaining was observed in 25 of 54 (46% primary pancreatic cancers compared to 0 of 33 normal pancreas specimens surveyed. GATA6 expression in xenografts was associated with specific microarray gene-expression patterns, enriched for GATA binding sites and mitochondrial oxidative phosphorylation activity. siRNA mediated knockdown of GATA6 in pancreatic cancer cell lines with amplification led to reduced cell proliferation, cell cycle progression, and colony formation. Our findings indicate that GATA6 amplification and overexpression contribute to the oncogenic phenotypes of pancreatic cancer cells, and identify GATA6 as a candidate lineage-specific oncogene in pancreatobiliary cancer, with implications for novel treatment strategies.

Agonists and inverse agonists for the herpesvirus 8-encoded constitutively active seven-transmembrane oncogene product, ORF-74

DEFF Research Database (Denmark)

Rosenkilde, M M; Kledal, T N; Bräuner-Osborne, Hans

1999-01-01

A number of CXC chemokines competed with similar, nanomolar affinity against 125I-interleukin-8 (IL-8) binding to ORF-74, a constitutively active seven-transmembrane receptor encoded by human herpesvirus 8. However, in competition against 125I-labeled growth-related oncogene (GRO)-alpha, the ORF-74...

Virus-Vectored Influenza Virus Vaccines

Science.gov (United States)

Tripp, Ralph A.; Tompkins, S. Mark

2014-01-01

Despite the availability of an inactivated vaccine that has been licensed for >50 years, the influenza virus continues to cause morbidity and mortality worldwide. Constant evolution of circulating influenza virus strains and the emergence of new strains diminishes the effectiveness of annual vaccines that rely on a match with circulating influenza strains. Thus, there is a continued need for new, efficacious vaccines conferring cross-clade protection to avoid the need for biannual reformulation of seasonal influenza vaccines. Recombinant virus-vectored vaccines are an appealing alternative to classical inactivated vaccines because virus vectors enable native expression of influenza antigens, even from virulent influenza viruses, while expressed in the context of the vector that can improve immunogenicity. In addition, a vectored vaccine often enables delivery of the vaccine to sites of inductive immunity such as the respiratory tract enabling protection from influenza virus infection. Moreover, the ability to readily manipulate virus vectors to produce novel influenza vaccines may provide the quickest path toward a universal vaccine protecting against all influenza viruses. This review will discuss experimental virus-vectored vaccines for use in humans, comparing them to licensed vaccines and the hurdles faced for licensure of these next-generation influenza virus vaccines. PMID:25105278

Kinase-dead ATM protein is highly oncogenic and can be preferentially targeted by Topo-isomerase I inhibitors.

Science.gov (United States)

Yamamoto, Kenta; Wang, Jiguang; Sprinzen, Lisa; Xu, Jun; Haddock, Christopher J; Li, Chen; Lee, Brian J; Loredan, Denis G; Jiang, Wenxia; Vindigni, Alessandro; Wang, Dong; Rabadan, Raul; Zha, Shan

2016-06-15

Missense mutations in ATM kinase, a master regulator of DNA damage responses, are found in many cancers, but their impact on ATM function and implications for cancer therapy are largely unknown. Here we report that 72% of cancer-associated ATM mutations are missense mutations that are enriched around the kinase domain. Expression of kinase-dead ATM (Atm(KD/-)) is more oncogenic than loss of ATM (Atm(-/-)) in mouse models, leading to earlier and more frequent lymphomas with Pten deletions. Kinase-dead ATM protein (Atm-KD), but not loss of ATM (Atm-null), prevents replication-dependent removal of Topo-isomerase I-DNA adducts at the step of strand cleavage, leading to severe genomic instability and hypersensitivity to Topo-isomerase I inhibitors. Correspondingly, Topo-isomerase I inhibitors effectively and preferentially eliminate Atm(KD/-), but not Atm-proficientor Atm(-/-) leukemia in animal models. These findings identify ATM kinase-domain missense mutations as a potent oncogenic event and a biomarker for Topo-isomerase I inhibitor based therapy.

Oncogenic action of beta, proton, alpha and electron radiation on the rat skin

International Nuclear Information System (INIS)

Burns, F.J.

1980-01-01

Rat skin is being utilized as an empirical model for testing dose and time related aspects of the oncogenic action of ionizing radiation, ultraviolet light, and polycyclic aromatic hydrocarbons. Molecular lesions in the skin DNA, including, strand breaks and thymine dimers, are being measured and compared to tumor induction. The induction and repair kinetics of molcular lesions are being compared to split dose repair. Modifiers and radiosensitizers are being utilized to test specific aspects of a chromosome breakage theory of radiation oncogenesis

PAK1 is a breast cancer oncogene that coordinately activates MAPK and MET signaling.

Science.gov (United States)

Shrestha, Y; Schafer, E J; Boehm, J S; Thomas, S R; He, F; Du, J; Wang, S; Barretina, J; Weir, B A; Zhao, J J; Polyak, K; Golub, T R; Beroukhim, R; Hahn, W C

2012-07-19

Activating mutations in the RAS family or BRAF frequently occur in many types of human cancers but are rarely detected in breast tumors. However, activation of the RAS-RAF-MEK-ERK MAPK pathway is commonly observed in human breast cancers, suggesting that other genetic alterations lead to activation of this signaling pathway. To identify breast cancer oncogenes that activate the MAPK pathway, we screened a library of human kinases for their ability to induce anchorage-independent growth in a derivative of immortalized human mammary epithelial cells (HMLE). We identified p21-activated kinase 1 (PAK1) as a kinase that permitted HMLE cells to form anchorage-independent colonies. PAK1 is amplified in several human cancer types, including 30--33% of breast tumor samples and cancer cell lines. The kinase activity of PAK1 is necessary for PAK1-induced transformation. Moreover, we show that PAK1 simultaneously activates MAPK and MET signaling; the latter via inhibition of merlin. Disruption of these activities inhibits PAK1-driven anchorage-independent growth. These observations establish PAK1 amplification as an alternative mechanism for MAPK activation in human breast cancer and credential PAK1 as a breast cancer oncogene that coordinately regulates multiple signaling pathways, the cooperation of which leads to malignant transformation.

Pokemon proto-oncogene in oral cancer: potential role in the early phase of tumorigenesis.

Science.gov (United States)

Sartini, D; Lo Muzio, L; Morganti, S; Pozzi, V; Di Ruscio, G; Rocchetti, R; Rubini, C; Santarelli, A; Emanuelli, M

2015-05-01

Oral squamous cell carcinoma (OSCC) represents about 90% of all oral neoplasms with a poor clinical prognosis. To improve survival of OSCC patients, it is fundamental to understand the basic molecular mechanisms characterizing oral carcinogenesis. Dysregulation of oncogenes and tumor suppressor genes seems to play a central role in tumorigenesis, including malignant transformation of the oral cavity. We analyzed the expression levels of the pro-oncogenic transcription factor Pokemon through real-time PCR, Western blot and immunohistochemistry in tumor, and normal oral tissue samples obtained from 22 patients with OSCC. The relationship between tumor characteristics and the level of Pokemon intratumor expression was also analyzed. Pokemon was significantly downregulated in OSCC. In particular, both mRNA and protein levels (tumor vs normal tissue) inversely correlated with histological grading, suggesting its potential role as a prognostic factor for OSCC. Moreover, a significant inverse correlation was found between Pokemon protein expression levels (OSCC vs normal oral mucosa) and tumor size, supporting the hypothesis that Pokemon could play an important role in the early phase of tumor expansion. This work shows that reduced expression of Pokemon is a peculiar feature of OSCC. Additional studies may establish the effective role of Pokemon in oral tumorigenesis. © 2014 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Dual paraneoplastic syndromes: small cell lung carcinoma-related oncogenic osteomalacia, and syndrome of inappropriate antidiuretic hormone secretion: report of a case and review of the literature.

Science.gov (United States)

Tantisattamo, Ekamol; Ng, Roland C K

2011-07-01

Acquired isolated renal phosphate wasting associated with a tumor, known as oncogenic osteomalacia or tumor-induced osteomalacia, is a rare paraneoplastic syndrome caused by overproduction of fibroblast growth factor 23. Oncogenic osteomalacia is usually associated with benign mesenchymal tumors. Syndrome of inappropriate antidiuretic hormone secretion (SIADH), on the other hand, is a common paraneoplastic syndrome caused by small cell carcinoma (SCC). Concomitant oncogenic osteomalacia and SIADH associated with SCC is very rare with only 4 other cases reported in the literature. The authors report a case of small cell lung cancer (SCLC)-related renal wasting hypophosphatemia and concurrent SIADH, and review the literature reporting 9 other cases of SCC associated with oncogenic osteomalacia. Almost half of reported cases of renal phosphate wasting associated with SCC concomitantly presented with SIADH. These cases had initial serum phosphorus level lower and survival periods shorter than those without SIADH. This rare combination of a dual paraneoplastic syndrome and low serum phosphorus may be a poor prognostic sign. In addition, both renal phosphate wasting and SIADH usually occur in a short period of time before identification of SCC. Therefore, renal wasting hypophosphatemia with concomitant SIADH/hyponatremia should prompt a search for SCC rather than a benign mesenchymal tumor.

Highly Efficient CRISPR/Cas9-Mediated Cloning and Functional Characterization of Gastric Cancer-Derived Epstein-Barr Virus Strains.

Science.gov (United States)

Kanda, Teru; Furuse, Yuki; Oshitani, Hitoshi; Kiyono, Tohru

2016-05-01

The Epstein-Barr virus (EBV) is etiologically linked to approximately 10% of gastric cancers, in which viral genomes are maintained as multicopy episomes. EBV-positive gastric cancer cells are incompetent for progeny virus production, making viral DNA cloning extremely difficult. Here we describe a highly efficient strategy for obtaining bacterial artificial chromosome (BAC) clones of EBV episomes by utilizing a CRISPR/Cas9-mediated strand break of the viral genome and subsequent homology-directed repair. EBV strains maintained in two gastric cancer cell lines (SNU719 and YCCEL1) were cloned, and their complete viral genome sequences were determined. Infectious viruses of gastric cancer cell-derived EBVs were reconstituted, and the viruses established stable latent infections in immortalized keratinocytes. While Ras oncoprotein overexpression caused massive vacuolar degeneration and cell death in control keratinocytes, EBV-infected keratinocytes survived in the presence of Ras expression. These results implicate EBV infection in predisposing epithelial cells to malignant transformation by inducing resistance to oncogene-induced cell death. Recent progress in DNA-sequencing technology has accelerated EBV whole-genome sequencing, and the repertoire of sequenced EBV genomes is increasing progressively. Accordingly, the presence of EBV variant strains that may be relevant to EBV-associated diseases has begun to attract interest. Clearly, the determination of additional disease-associated viral genome sequences will facilitate the identification of any disease-specific EBV variants. We found that CRISPR/Cas9-mediated cleavage of EBV episomal DNA enabled the cloning of disease-associated viral strains with unprecedented efficiency. As a proof of concept, two gastric cancer cell-derived EBV strains were cloned, and the infection of epithelial cells with reconstituted viruses provided important clues about the mechanism of EBV-mediated epithelial carcinogenesis. This

Molecular basis of hepatitis C virus -associated hepatocarcinogenesis

Directory of Open Access Journals (Sweden)

Isabelle Chemin

2007-02-01

Full Text Available

In areas with an intermediate rate of Hepatocellular Carcinoma (HCC such as Western Europe and Japan, hepatitis C is the predominant cause, whereas in low rate areas such as Western Europe and North USA, HCC is often related to other factors as alcoholic liver disease. There is a rising incidence in HCC in developed countries during the last two decades, due to the increasing rate of hepatitis C infection and improvement of the clinical management of cirrhosis (most of the time appear after cirrhosis, the total number of HCC cases annually registered should be multiplied by 3 until 2020.

The pathogenesis of HCC in HCV infection has extensively been analysed. Hepatitis C virus-induced chronic inflammation and the effects of cytokines in the development of fibrosis and liver cell proliferation are considered as one of the major pathogenic mechanisms. Increasing experimental evidence suggests that HCV contributes to HCC by directly modulating pathways that promote the malignant transformation of hepatocytes. Hepatitis C virus is an RNA virus that does not integrate into the host genome but HCV proteins interact with many host-cell factors well beyond their roles in the viral life cycle and are involved in a wide range of activities at least in vitro, including cell signalling, transcription, cell proliferation, apoptosis, membrane rearrangements, vesicular trafficking and translational regulation. At least four of the HCV gene products, namely HCV core, NS3, NS4B and NS5A, have been shown to exhibit transformation potential in tissue culture and several potentially oncogenic pathways have been shown to be altered by the expression of HCV proteins. Both HCV core and NS5A induce the accumulation of wild-type betacatenin and the Wnt-beta-catenin pathway emerges as a common target

Disruption of PH–kinase domain interactions leads to oncogenic activation of AKT in human cancers

Science.gov (United States)

Parikh, Chaitali; Janakiraman, Vasantharajan; Wu, Wen-I; Foo, Catherine K.; Kljavin, Noelyn M.; Chaudhuri, Subhra; Stawiski, Eric; Lee, Brian; Lin, Jie; Li, Hong; Lorenzo, Maria N.; Yuan, Wenlin; Guillory, Joseph; Jackson, Marlena; Rondon, Jesus; Franke, Yvonne; Bowman, Krista K.; Sagolla, Meredith; Stinson, Jeremy; Wu, Thomas D.; Wu, Jiansheng; Stokoe, David; Stern, Howard M.; Brandhuber, Barbara J.; Lin, Kui; Skelton, Nicholas J.; Seshagiri, Somasekar

2012-01-01

The protein kinase v-akt murine thymoma viral oncogene homolog (AKT), a key regulator of cell survival and proliferation, is frequently hyperactivated in human cancers. Intramolecular pleckstrin homology (PH) domain–kinase domain (KD) interactions are important in maintaining AKT in an inactive state. AKT activation proceeds after a conformational change that dislodges the PH from the KD. To understand these autoinhibitory interactions, we generated mutations at the PH–KD interface and found that most of them lead to constitutive activation of AKT. Such mutations are likely another mechanism by which activation may occur in human cancers and other diseases. In support of this likelihood, we found somatic mutations in AKT1 at the PH–KD interface that have not been previously described in human cancers. Furthermore, we show that the AKT1 somatic mutants are constitutively active, leading to oncogenic signaling. Additionally, our studies show that the AKT1 mutants are not effectively inhibited by allosteric AKT inhibitors, consistent with the requirement for an intact PH–KD interface for allosteric inhibition. These results have important implications for therapeutic intervention in patients with AKT mutations at the PH–KD interface. PMID:23134728

Role of micro-RNAs in LRF and BCL6 oncogenes regulation

International Nuclear Information System (INIS)

Rainaldi, G.

2009-01-01

Micro RNAs (miRNAs) are short 20-22 nucleotide RNA molecules with an important role in the regulation of gene expression at the post-transcriptional level. MiRNA levels have been shown to change markedly in tumors and their expression profile is currently used to classify and diagnose some tumours. MiRNAs have been classified either as oncogenes (overespressed in tumors) or as tumor suppressor (down regulated), and in certain cases they can behave as both depending on the type of tumor. In many cases miRNAs and transcription factors interact directly so that transcriptional and post-transcriptional regulation of gene expression are finely regulated

C/EBPβ represses p53 to promote cell survival downstream of DNA damage independent of oncogenic Ras and p19Arf

Science.gov (United States)

Ewing, SJ; Zhu, S; Zhu, F; House, JS; Smart, RC

2013-01-01

CCAAT/enhancer-binding protein-β (C/EBPβ) is a mediator of cell survival and tumorigenesis. When C/EBPβ−/− mice are treated with carcinogens that produce oncogenic Ras mutations in keratinocytes, they respond with abnormally elevated keratinocyte apoptosis and a block in skin tumorigenesis. Although this aberrant carcinogen-induced apoptosis results from abnormal upregulation of p53, it is not known whether upregulated p53 results from oncogenic Ras and its ability to induce p19Arf and/or activate DNA-damage response pathways or from direct carcinogen-induced DNA damage. We report that p19Arf is dramatically elevated in C/EBPβ−/− epidermis and that C/EBPβ represses a p19Arf promoter reporter. To determine whether p19Arf is responsible for the proapoptotic phenotype in C/EBPβ−/− mice, C/EBPβ−/−;p19Arf−/− mice were generated. C/EBPβ−/−;p19Arf−/− mice responded to carcinogen treatment with increased p53 and apoptosis, indicating p19Arf is not essential. To ascertain whether oncogenic Ras activation induces aberrant p53 and apoptosis in C/EBPβ−/− epidermis, we generated K14-ER:Ras; C/EBPβ−/− mice. Oncogenic Ras activation induced by 4-hydroxytamoxifen did not produce increased p53 or apoptosis. Finally, when C/EBPβ−/− mice were treated with differing types of DNA-damaging agents, including alkylating chemotherapeutic agents, they displayed aberrant levels of p53 and apoptosis. These results indicate that C/EBPβ represses p53 to promote cell survival downstream of DNA damage and suggest that inhibition of C/EBPβ may be a target for cancer cotherapy to increase the efficacy of alkylating chemotherapeutic agents. PMID:18636078

Replication and interaction of herpes simplex virus and human papillomavirus in differentiating host epithelial tissue

International Nuclear Information System (INIS)

Meyers, Craig; Andreansky, Samita S.; Courtney, Richard J.

2003-01-01

We have investigated the interactions and consequences of superinfecting and coreplication of human papillomavirus (HPV) and herpes simplex virus (HSV) in human epithelial organotypic (raft) culture tissues. In HPV-positive tissues, HSV infection and replication induced significant cytopathic effects (CPE), but the tissues were able to recover and maintain a certain degree of tissue integrity and architecture. HPV31b not only maintained the episomal state of its genomic DNA but also maintained its genomic copy number even during times of extensive HSV-induced CPE. E2 transcripts encoded by HPV31b were undetectable even though HPV31b replication was maintained in HSV- infected raft tissues. Expression of HPV31b oncogenes (E6 and E7) was also repressed but to a lesser degree than was E2 expression. The extent of CPE induced by HSV is dependent on the magnitude of HPV replication and gene expression at the time of HSV infection. During active HSV infection, HPV maintains its genomic copy number even though genes required for its replication were repressed. These studies provide new insight into the complex interaction between two common human sexually transmitted viruses in an in vitro system, modeling their natural host tissue in vivo

Oncogene-induced senescence is part of the tumorigenesis barrier imposed by DNA damage checkpoints

DEFF Research Database (Denmark)

Bartkova, Jirina; Rezaei, Nousin; Liontos, Michalis

2006-01-01

Recent studies have indicated the existence of tumorigenesis barriers that slow or inhibit the progression of preneoplastic lesions to neoplasia. One such barrier involves DNA replication stress, which leads to activation of the DNA damage checkpoint and thereby to apoptosis or cell cycle arrest...... and senescence markers cosegregate closely. Thus, senescence in human preneoplastic lesions is a manifestation of oncogene-induced DNA replication stress and, together with apoptosis, provides a barrier to malignant progression....

The Agrobacterium rhizogenes oncogenes rolB and ORF13 increase formation of generative shoots and induce dwarfism in Arabidopsis thaliana (L.) Heynh.

Science.gov (United States)

Kodahl, Nete; Müller, Renate; Lütken, Henrik

2016-11-01

Plant transformation with the wild type Ri plasmid T-DNA of Agrobacterium rhizogenes is a promising method for breeding of compact plants and has been the subject of numerous studies. However, knowledge concerning the isolated functions of single genes and ORFs from the plasmid is limited. The rolB and ORF13 oncogenes of A. rhizogenes show considerable promise in plant breeding, but have not been comprehensively studied. Detailed information regarding the morphological impact of specific genes of the Ri plasmid will allow for optimized targeted breeding of plants transformed with the wild type Ri plasmid T-DNA. rolB and ORF13 were recombined into the genome of Arabidopsis thaliana using Gateway ® cloning and the effect on plant growth was assessed biometrically throughout the plants' life cycle. rolB-lines exhibited dwarfing, early necrosis of rosette leaves, altered leaf and flower morphology, and developed an increased number of inflorescences per rosette area compared to the wild type. ORF13-lines were extremely dwarfed, attaining only ca. 1% of the rosette area of the wild type, leaf and flower size was reduced, and the shape modified. The study documents that the traits inferred by the rolB oncogene yield plants with increased formation of generative shoots, but also result in some degree of premature senescence of vegetative organs. The extreme dwarfism seen in ORF13-lines indicate that this oncogene may be more important in the dwarfing response of plants transformed with the wild type Ri plasmid T-DNA than previously assumed and that transformation with this oncogene induces a very compact phenotype. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Use of glycolytic pathways for inhibiting or measuring oncogenic signaling

Science.gov (United States)

Onodera, Yasuhito; Bissell, Mina

2017-06-27

Disclosed are methods in which glucose metabolism is correlated to oncogenesis through certain specific pathways; inhibition of certain enzymes is shown to interfere with oncogenic signaling, and measurement of certain enzyme levels is correlated with patient survival. The present methods comprise measuring level of expression of at least one of the enzymes involved in glucose uptake or metabolism, wherein increased expression of the at least one of the enzymes relative to expression in a normal cell correlates with poor prognosis of disease in a patient. Preferably the genes whose expression level is measured include GLUT3, PFKP, GAPDH, ALDOC, LDHA and GFPT2. Also disclosed are embodiments directed towards downregulating the expression of some genes in glucose uptake and metabolism.

Alteration in gene expression profile and oncogenicity of esophageal squamous cell carcinoma by RIZ1 upregulation.

Science.gov (United States)

Dong, Shang-Wen; Li, Dong; Xu, Cong; Sun, Pei; Wang, Yuan-Guo; Zhang, Peng

2013-10-07

To investigate the effect of retinoblastoma protein-interacting zinc finger gene 1 (RIZ1) upregulation in gene expression profile and oncogenicity of human esophageal squamous cell carcinoma (ESCC) cell line TE13. TE13 cells were transfected with pcDNA3.1(+)/RIZ1 and pcDNA3.1(+). Changes in gene expression profile were screened and the microarray results were confirmed by reverse transcription-polymerase chain reaction (RT-PCR). Nude mice were inoculated with TE13 cells to establish ESCC xenografts. After two weeks, the inoculated mice were randomly divided into three groups. Tumors were injected with normal saline, transfection reagent pcDNA3.1(+) and transfection reagent pcDNA3.1(+)/RIZ1, respectively. Tumor development was quantified, and changes in gene expression of RIZ1 transfected tumors were detected by RT-PCR and Western blotting. DNA microarray data showed that RIZ1 transfection induced widespread changes in gene expression profile of cell line TE13, with 960 genes upregulated and 1163 downregulated. Treatment of tumor xenografts with RIZ1 recombinant plasmid significantly inhibited tumor growth, decreased tumor size, and increased expression of RIZ1 mRNA compared to control groups. The changes in gene expression profile were also observed in vivo after RIZ1 transfection. Most of the differentially expressed genes were associated with cell development, supervision of viral replication, lymphocyte costimulatory and immune system development in esophageal cells. RIZ1 gene may be involved in multiple cancer pathways, such as cytokine receptor interaction and transforming growth factor beta signaling. The development and progression of esophageal cancer are related to the inactivation of RIZ1. Virus infection may also be an important factor.

Oncogenic functions of the cancer-testis antigen SSX on the proliferation, survival, and signaling pathways of cancer cells.

Directory of Open Access Journals (Sweden)

Padraig D'Arcy

Full Text Available SSX is a transcription factor with elusive oncogenic functions expressed in a variety of human tumors of epithelial and mesenchymal origin. It has raised substantial interest as a target for cancer therapy since it elicits humoral responses and displays restricted expression to cancer, spermatogonia and mesenchymal stem cells. Here, we investigated the oncogenic properties of SSX by employing a RNA interference to knock-down the endogenous expression of SSX in melanoma and osteosarcoma cell lines. Depletion of SSX expression resulted in reduced proliferation with cells accumulating in the G1 phase of the cell cycle. We found that the growth promoting and survival properties of SSX are mediated in part though modulation of MAPK/Erk and Wnt signaling pathways, since SSX silencing inhibited Erk-mediated signaling and transcription of cMYC and Akt-1. We also found that SSX forms a transient complex with β-catenin at the G1-S phase boundary resulting in the altered expression of β-catenin target genes such as E-cadherin, snail-2 and vimentin, involved in epithelial-mesenchymal transitions. Importantly the silencing of SSX expression in in vivo significantly impaired the growth of melanoma tumor xenografts. Tumor biopsies from SSX silenced tumors displayed reduced cyclin A staining, indicative of low proliferation and predominantly cycloplasmic β-catenin compared to SSX expressing tumors. The present study demonstrates a previously unknown function of SSX, that as an oncogene and as a tumor target for the development of novel anti-cancer drugs.

Merkel cell polyomavirus and Merkel cell carcinoma.

Science.gov (United States)

DeCaprio, James A

2017-10-19

Merkel cell polyomavirus (MCPyV) causes the highly aggressive and relatively rare skin cancer known as Merkel cell carcinoma (MCC). MCPyV also causes a lifelong yet relatively innocuous infection and is one of 14 distinct human polyomaviruses species. Although polyomaviruses typically do not cause illness in healthy individuals, several can cause catastrophic diseases in immunocompromised hosts. MCPyV is the only polyomavirus clearly associated with human cancer. How MCPyV causes MCC and what oncogenic events must transpire to enable this virus to cause MCC is the focus of this essay.This article is part of the themed issue 'Human oncogenic viruses'. © 2017 The Author(s).

Prox1-Heterozygosis Sensitizes the Pancreas to Oncogenic Kras-Induced Neoplastic Transformation

Directory of Open Access Journals (Sweden)

Yiannis Drosos

2016-03-01

Full Text Available The current paradigm of pancreatic neoplastic transformation proposes an initial step whereby acinar cells convert into acinar-to-ductal metaplasias, followed by progression of these lesions into neoplasias under sustained oncogenic activity and inflammation. Understanding the molecular mechanisms driving these processes is crucial to the early diagnostic and prevention of pancreatic cancer. Emerging evidence indicates that transcription factors that control exocrine pancreatic development could have either, protective or facilitating roles in the formation of preneoplasias and neoplasias in the pancreas. We previously identified that the homeodomain transcription factor Prox1 is a novel regulator of mouse exocrine pancreas development. Here we investigated whether Prox1 function participates in early neoplastic transformation using in vivo, in vitro and in silico approaches. We found that Prox1 expression is transiently re-activated in acinar cells undergoing dedifferentiation and acinar-to-ductal metaplastic conversion. In contrast, Prox1 expression is largely absent in neoplasias and tumors in the pancreas of mice and humans. We also uncovered that Prox1-heterozygosis markedly increases the formation of acinar-to-ductal-metaplasias and early neoplasias, and enhances features associated with inflammation, in mouse pancreatic tissues expressing oncogenic Kras. Furthermore, we discovered that Prox1-heterozygosis increases tissue damage and delays recovery from inflammation in pancreata of mice injected with caerulein. These results are the first demonstration that Prox1 activity protects pancreatic cells from acute tissue damage and early neoplastic transformation. Additional data in our study indicate that this novel role of Prox1 involves suppression of pathways associated with inflammatory responses and cell invasiveness.

Enhanced inflammation and attenuated tumor suppressor pathways are associated with oncogene-induced lung tumors in aged mice

Science.gov (United States)

Aging is often accompanied by a dramatic increase in cancer susceptibility. To gain insights into how aging affects tumor susceptibility, we generated a conditional mouse model in which oncogenic KrasG12D was activated specifically in lungs of young (3-5 months) and old (19-24 months) mice. Activati...

Characteristics of lentiviral vectors harboring the proximal promoter of the vav proto-oncogene: a weak and efficient promoter for gene therapy.

Science.gov (United States)

Almarza, Elena; Río, Paula; Meza, Nestor W; Aldea, Montserrat; Agirre, Xabier; Guenechea, Guillermo; Segovia, José C; Bueren, Juan A

2007-08-01

Recent published data have shown the efficacy of gene therapy treatments of certain monogenic diseases. Risks of insertional oncogenesis, however, indicate the necessity of developing new vectors with weaker or cell-restricted promoters to minimize the trans-activation activity of integrated proviruses. We have inserted the proximal promoter of the vav proto-oncogene into self-inactivating lentiviral vectors (vav-LVs) and investigated the expression pattern and therapeutic efficacy of these vectors. Compared with other LVs frequently used in gene therapy, vav-LVs mediated a weak, though homogeneous and stable, expression in in vitro-cultured cells. Transplantation experiments using transduced mouse bone marrow and human CD34(+) cells confirmed the stable activity of the promoter in vivo. To investigate whether the weak activity of this promoter was compatible with a therapeutic effect, a LV expressing the Fanconi anemia A (FANCA) gene was constructed (vav-FANCA LV). Although this vector induced a low expression of FANCA, compared to the expression induced by a LV harboring the spleen focus-forming virus (SFFV) promoter, the two vectors corrected the phenotype of cells from a patient with FA-A with the same efficacy. We propose that self-inactivating vectors harboring weak promoters, such as the vav promoter, will improve the safety of gene therapy and will be of particular interest for the treatment of diseases where a high expression of the transgene is not required.

AKT activation drives the nuclear localization of CSE1L and a pro-oncogenic transcriptional activation in ovarian cancer cells

Energy Technology Data Exchange (ETDEWEB)

Lorenzato, Annalisa; Biolatti, Marta [Department of Oncology, University of Torino School of Medicine, Torino (Italy); Institute for Cancer Research at Candiolo, Candiolo, Torino (Italy); Delogu, Giuseppe [Department of Biomedical Sciences-Histology, University of Sassari, Sassari (Italy); Capobianco, Giampiero [Department of Surgical, Microsurgical and Medical Sciences, University of Sassari, Sassari (Italy); Farace, Cristiano [Department of Biomedical Sciences-Histology, University of Sassari, Sassari (Italy); Dessole, Salvatore; Cossu, Antonio; Tanda, Francesco [Department of Surgical, Microsurgical and Medical Sciences, University of Sassari, Sassari (Italy); Madeddu, Roberto [Department of Biomedical Sciences-Histology, University of Sassari, Sassari (Italy); National Institute of Biostructures and Biosystems, Rome (Italy); Olivero, Martina [Department of Oncology, University of Torino School of Medicine, Torino (Italy); Institute for Cancer Research at Candiolo, Candiolo, Torino (Italy); Di Renzo, Maria Flavia, E-mail: mariaflavia.direnzo@unito.it [Department of Oncology, University of Torino School of Medicine, Torino (Italy); Institute for Cancer Research at Candiolo, Candiolo, Torino (Italy)

2013-10-15

The human homolog of the yeast cse1 gene (CSE1L) is over-expressed in ovarian cancer. CSE1L forms complex with Ran and importin-α and has roles in nucleocytoplasmic traffic and gene expression. CSE1L accumulated in the nucleus of ovarian cancer cell lines, while it was localized also in the cytoplasm of other cancer cell lines. Nuclear localization depended on AKT, which was constitutively active in ovarian cancer cells, as the CSE1L protein translocated to the cytoplasm when AKT was inactivated. Moreover, the expression of a constitutively active AKT forced the translocation of CSE1L from the cytoplasm to the nucleus in other cancer cells. Nuclear accrual of CSE1L was associated to the nuclear accumulation of the phosphorylated Ran Binding protein 3 (RanBP3), which depended on AKT as well. Also in samples of human ovarian cancer, AKT activation was associated to nuclear accumulation of CSE1L and phosphorylation of RanBP3. Expression profiling of ovarian cancer cells after CSE1L silencing showed that CSE1L was required for the expression of genes promoting invasion and metastasis. In agreement, CSE1L silencing impaired motility and invasiveness of ovarian cancer cells. Altogether these data show that in ovarian cancer cells activated AKT by affecting RanBP3 phosphorylation determines the nuclear accumulation of CSE1L and likely the nuclear concentration of transcription factors conveying pro-oncogenic signals. - highlights: • CSE1L is a key player in nucleocytoplasmic traffic by forming complex with Ran. • AKT phosphorylates RanBP3 that regulates the nucleocytoplasmic gradient of Ran. • The activated oncogenic AKT drives the nuclear accumulation of CSE1L. • CSE1L in the nucleus up-regulates genes conveying pro-oncogenic signals. • CSE1L might contribute to tumor progression driven by the activated oncogenic AKT.

AKT activation drives the nuclear localization of CSE1L and a pro-oncogenic transcriptional activation in ovarian cancer cells

International Nuclear Information System (INIS)

Lorenzato, Annalisa; Biolatti, Marta; Delogu, Giuseppe; Capobianco, Giampiero; Farace, Cristiano; Dessole, Salvatore; Cossu, Antonio; Tanda, Francesco; Madeddu, Roberto; Olivero, Martina; Di Renzo, Maria Flavia

2013-01-01

The human homolog of the yeast cse1 gene (CSE1L) is over-expressed in ovarian cancer. CSE1L forms complex with Ran and importin-α and has roles in nucleocytoplasmic traffic and gene expression. CSE1L accumulated in the nucleus of ovarian cancer cell lines, while it was localized also in the cytoplasm of other cancer cell lines. Nuclear localization depended on AKT, which was constitutively active in ovarian cancer cells, as the CSE1L protein translocated to the cytoplasm when AKT was inactivated. Moreover, the expression of a constitutively active AKT forced the translocation of CSE1L from the cytoplasm to the nucleus in other cancer cells. Nuclear accrual of CSE1L was associated to the nuclear accumulation of the phosphorylated Ran Binding protein 3 (RanBP3), which depended on AKT as well. Also in samples of human ovarian cancer, AKT activation was associated to nuclear accumulation of CSE1L and phosphorylation of RanBP3. Expression profiling of ovarian cancer cells after CSE1L silencing showed that CSE1L was required for the expression of genes promoting invasion and metastasis. In agreement, CSE1L silencing impaired motility and invasiveness of ovarian cancer cells. Altogether these data show that in ovarian cancer cells activated AKT by affecting RanBP3 phosphorylation determines the nuclear accumulation of CSE1L and likely the nuclear concentration of transcription factors conveying pro-oncogenic signals. - highlights: • CSE1L is a key player in nucleocytoplasmic traffic by forming complex with Ran. • AKT phosphorylates RanBP3 that regulates the nucleocytoplasmic gradient of Ran. • The activated oncogenic AKT drives the nuclear accumulation of CSE1L. • CSE1L in the nucleus up-regulates genes conveying pro-oncogenic signals. • CSE1L might contribute to tumor progression driven by the activated oncogenic AKT

PAK1 is a breast cancer oncogene that coordinately activates MAPK and MET signaling

OpenAIRE

Shrestha, Yashaswi; Schafer, Eric J.; Boehm, Jesse S.; Thomas, Sapana R.; He, Frank; Du, Jinyan; Wang, Shumei; Barretina, Jordi; Weir, Barbara A.; Zhao, Jean J.; Polyak, Kornelia; Golub, Todd R.; Beroukhim, Rameen; Hahn, William C.

2011-01-01

Activating mutations in the RAS family or BRAF frequently occur in many types of human cancers but are rarely detected in breast tumors. However, activation of the RAS-RAF-MEK-ERK Mitogen-Activated Protein Kinase (MAPK) pathway is commonly observed in human breast cancers, suggesting that other genetic alterations lead to activation of this signaling pathway. To identify breast cancer oncogenes that activate the MAPK pathway, we screened a library of human kinases for their ability to induce ...

WIP-YAP/TAZ as A New Pro-Oncogenic Pathway in Glioma

Directory of Open Access Journals (Sweden)

Sergio Rivas

2018-06-01

Full Text Available Wild-type p53 (wtp53 is described as a tumour suppressor gene, and mutations in p53 occur in many human cancers. Indeed, in high-grade malignant glioma, numerous molecular genetics studies have established central roles of RTK-PI3K-PTEN and ARF-MDM2-p53 INK4a-RB pathways in promoting oncogenic capacity. Deregulation of these signalling pathways, among others, drives changes in the glial/stem cell state and environment that permit autonomous growth. The initially transformed cell may undergo subsequent modifications, acquiring a more complete tumour-initiating phenotype responsible for disease advancement to stages that are more aggressive. We recently established that the oncogenic activity of mutant p53 (mtp53 is driven by the actin cytoskeleton-associated protein WIP (WASP-interacting protein, correlated with tumour growth, and more importantly that both proteins are responsible for the tumour-initiating cell phenotype. We reported that WIP knockdown in mtp53-expressing glioblastoma greatly reduced proliferation and growth capacity of cancer stem cell (CSC-like cells and decreased CSC-like markers, such as hyaluronic acid receptor (CD44, prominin-1 (CD133, yes-associated protein (YAP and transcriptional co-activator with PDZ-binding motif (TAZ. We thus propose a new CSC signalling pathway downstream of mtp53 in which Akt regulates WIP and controls YAP/TAZ stability. WIP drives a mechanism that stimulates growth signals, promoting YAP/TAZ and β-catenin stability in a Hippo-independent fashion, which allows cells to coordinate processes such as proliferation, stemness and invasiveness, which are key factors in cancer progression. Based on this multistep tumourigenic model, it is tantalizing to propose that WIP inhibitors may be applied as an effective anti-cancer therapy.

P53 suppresses expression of the 14-3-3gamma oncogene

Directory of Open Access Journals (Sweden)

Qi Wenqing

2011-08-01

Full Text Available Abstract Background 14-3-3 proteins are a family of highly conserved proteins that are involved in a wide range of cellular processes. Recent evidence indicates that some of these proteins have oncogenic activity and that they may promote tumorigenesis. We previously showed that one of the 14-3-3 family members, 14-3-3gamma, is over expressed in human lung cancers and that it can induce transformation of rodent cells in vitro. Methods qRTPCR and Western blot analysis were performed to examine 14-3-3gamma expression in non-small cell lung cancers (NSCLC. Gene copy number was analyzed by qPCR. P53 mutations were detected by direct sequencing and also by western blot. CHIP and yeast one hybrid assays were used to detect p53 binding to 14-3-3gamma promoter. Results Quantitative rtPCR results showed that the expression level of 14-3-3gamma was elevated in the majority of NSCLC that we examined which was also consistent with protein expression. Further analysis of the expression pattern of 14-3-3gamma in lung tumors showed a correlation with p53 mutations suggesting that p53 might suppress 14-3-3 gamma expression. Analysis of the gamma promoter sequence revealed the presence of a p53 consensus binding motif and in vitro assays demonstrated that wild-type p53 bound to this motif when activated by ionizing radiation. Deletion of the p53 binding motif eliminated p53's ability to suppress 14-3-3gamma expression. Conclusion Increased expression of 14-3-3gamma in lung cancer coincides with loss of functional p53. Hence, we propose that 14-3-3gamma's oncogenic activities cooperate with loss of p53 to promote lung tumorigenesis.

mTORC1 is a critical mediator of oncogenic Semaphorin3A signaling

Energy Technology Data Exchange (ETDEWEB)

Yamada, Daisuke; Kawahara, Kohichi; Maeda, Takehiko, E-mail: maeda@nupals.ac.jp

2016-08-05

Aberration of signaling pathways by genetic mutations or alterations in the surrounding tissue environments can result in tumor development or metastasis. However, signaling molecules responsible for these processes have not been completely elucidated. Here, we used mouse Lewis lung carcinoma cells (LLC) to explore the mechanism by which the oncogenic activity of Semaphorin3A (Sema3A) signaling is regulated. Sema3A knockdown by shRNA did not affect apoptosis, but decreased cell proliferation in LLCs; both the mammalian target of rapamycin complex 1 (mTORC1) level and glycolytic activity were also decreased. In addition, Sema3A knockdown sensitized cells to inhibition of oxidative phosphorylation by oligomycin, but conferred resistance to decreased cell viability induced by glucose starvation. Furthermore, recombinant SEMA3A rescued the attenuation of cell proliferation and glycolytic activity in LLCs after Sema3A knockdown, whereas mTORC1 inhibition by rapamycin completely counteracted this effect. These results demonstrate that Sema3A signaling exerts its oncogenic effect by promoting an mTORC1-mediated metabolic shift from oxidative phosphorylation to aerobic glycolysis. -- Highlights: •Sema3A knockdown decreased proliferation of Lewis lung carcinoma cells (LLCs). •Sema3A knockdown decreased mTORC1 levels and glycolytic activity in LLCs. •Sema3A knockdown sensitized cells to inhibition of oxidative phosphorylation. •Sema3A promotes shift from oxidative phosphorylation to aerobic glycolysis via mTORC1.

A novel oncogenic BTK isoform is overexpressed in colon cancers and required for RAS-mediated transformation

DEFF Research Database (Denmark)

Grassilli, E; Pisano, F; Cialdella, A

2016-01-01

Bruton's tyrosine kinase (BTK) is essential for B-cell proliferation/differentiation and it is generally believed that its expression and function are limited to bone marrow-derived cells. Here, we report the identification and characterization of p65BTK, a novel isoform abundantly expressed in c...... therapeutic approach.Oncogene advance online publication, 25 January 2016; doi:10.1038/onc.2015.504....

The Tax oncogene enhances ELL incorporation into p300 and P-TEFb containing protein complexes to activate transcription.

Science.gov (United States)

Fufa, Temesgen D; Byun, Jung S; Wakano, Clay; Fernandez, Alfonso G; Pise-Masison, Cynthia A; Gardner, Kevin

2015-09-11

The eleven-nineteen lysine-rich leukemia protein (ELL) is a key regulator of RNA polymerase II mediated transcription. ELL facilitates RNA polymerase II transcription pause site entry and release by dynamically interacting with p300 and the positive transcription elongation factor b (P-TEFb). In this study, we investigated the role of ELL during the HTLV-1 Tax oncogene induced transactivation. We show that ectopic expression of Tax enhances ELL incorporation into p300 and P-TEFb containing transcriptional complexes and the subsequent recruitment of these complexes to target genes in vivo. Depletion of ELL abrogates Tax induced transactivation of the immediate early genes Fos, Egr2 and NF-kB, suggesting that ELL is an essential cellular cofactor of the Tax oncogene. Thus, our study identifies a novel mechanism of ELL-dependent transactivation of immediate early genes by Tax and provides the rational for further defining the genome-wide targets of Tax and ELL. Published by Elsevier Inc.

The Effect of Coexistence of a Pair of Mutated Oncogenes on the Survival Rate of Invasive Breast Carcinoma Patients

Science.gov (United States)

Nair, D. R.

2017-12-01

The purpose of this project was to determine the effect of two mutated oncogenes on the survival rate from invasive breast carcinoma when in comparison to the mutation of a single oncogene on the survival rate. An oncogene is defined as a gene, that when mutated, can lead to cancer. The two oncogenes used in this project were human epidermal growth factor receptor 2 (HER2) and c-myc (MYC). HER2 and MYC are both oncogenes that contribute to the formation of cancer. HER2 proteins are receptors on breast cells, and when the HER2 gene is mutated, there is an overexpression of HER2 protein on the breast cell. This makes the breast cells proliferate uncontrollably. MYC is a gene that codes for a transcription factor that plays a role in cell cycle progression. The overexpression of MYC also leads to the proliferation of cells. I hypothesized that if there is a mutation in both the MYC and HER2 genes, then the survival rate of invasive breast carcinoma patients will be lower compared to patients with the mutations of only MYC or HER2. To test this hypothesis, we conducted individual gene searches in CBioPortal for HER2 in the datasets from the studies titled TCGA Nature 2012, TCGA Cell 2015, and TCGA Provisional. We conducted individual gene searches in CBioPortal for MYC in the same datasets. The survival rate data was then exported and analyzed for patients with mutations of either HER2 or MYC and with mutations of both genes. To determine the cases that had both HER2 and MYC mutations, we found the overlapping cases in both HER2 and MYC groups for all three datasets. We calculated the median of the survival data for cases where either HER2 or MYC was mutated and cases where both MYC and HER2 were mutated. From the first dataset, the median of MYC data was 95.53, HER2 data was 95.83, and both HER2 and MYC data was 91.24. In the second dataset, the median of MYC data was 92.17 , HER2 data was 93.5, and both HER2 and MYC data was 87.95 . In the third dataset, the median

Characterization of a novel oncogenic K-ras mutation in colon cancer

International Nuclear Information System (INIS)

Akagi, Kiwamu; Uchibori, Ryosuke; Yamaguchi, Kensei; Kurosawa, Keiko; Tanaka, Yoichiro; Kozu, Tomoko

2007-01-01

Activating mutations of RAS are frequently observed in subsets of human cancers, indicating that RAS activation is involved in tumorigenesis. Here, we identified and characterized a novel G to T transversion mutation of the K-ras gene at the third position of codon 19 (TTG) which substituted phenylalanine for leucine in 3 primary colon carcinomas. Biological and biochemical activity was examined using transformed NIH3T3 cells expressing mutant or wild-type K-ras. Transformants harboring the K-ras mutation at codon 19 showed proliferative capacity under serum-starved conditions, less contact inhibition, anchorage-independent growth, tumorigenicity in nude mice and elevation of active Ras-GTP levels. These results indicated that this novel mutation possesses high oncogenic activity

The MHC-II transactivator CIITA, a restriction factor against oncogenic HTLV-1 and HTLV-2 retroviruses: similarities and differences in the inhibition of Tax-1 and Tax-2 viral transactivators

Science.gov (United States)

Forlani, Greta; Abdallah, Rawan; Accolla, Roberto S.; Tosi, Giovanna

2013-01-01

The activation of CD4+ T helper cells is strictly dependent on the presentation of antigenic peptides by MHC class II (MHC-II) molecules. MHC-II expression is primarily regulated at the transcriptional level by the AIR-1 gene product CIITA (class II transactivator). Thus, CIITA plays a pivotal role in the triggering of the adaptive immune response against pathogens. Besides this well known function, we recently found that CIITA acts as an endogenous restriction factor against HTLV-1 (human T cell lymphotropic virus type 1) and HTLV-2 oncogenic retroviruses by targeting their viral transactivators Tax-1 and Tax-2, respectively. Here we review our findings on CIITA-mediated inhibition of viral replication and discuss similarities and differences in the molecular mechanisms by which CIITA specifically counteracts the function of Tax-1 and Tax-2 molecules. The dual function of CIITA as a key regulator of adaptive and intrinsic immunity represents a rather unique example of adaptation of host-derived factors against pathogen infections during evolution. PMID:23986750

Overexpression of hepatoma-derived growth factor in melanocytes does not lead to oncogenic transformation

International Nuclear Information System (INIS)

Sedlmaier, Angela; Wernert, Nicolas; Gallitzendörfer, Rainer; Abouzied, Mekky M; Gieselmann, Volkmar; Franken, Sebastian

2011-01-01

HDGF is a growth factor which is overexpressed in a wide range of tumors. Importantly, expression levels were identified as a prognostic marker in some types of cancer such as melanoma. To investigate the presumed oncogenic/transforming capacity of HDGF, we generated transgenic mice overexpressing HDGF in melanocytes. These mice were bred with mice heterozygous for a defective copy of the Ink4a tumor suppressor gene and were exposed to UV light to increase the risk for tumor development both genetically and physiochemically. Mice were analyzed by immunohistochemistry and Western blotting. Furthermore, primary melanocytes were isolated from different strains created. Transgenic animals overexpressed HDGF in hair follicle melanocytes. Interestingly, primary melanocytes isolated from transgenic animals were not able to differentiate in vitro whereas cells isolated from wild type and HDGF-deficient animals were. Although, HDGF -/- /Ink4a +/- mice displayed an increased number of epidermoid cysts after exposure to UV light, no melanomas or premelanocytic alterations could be detected in this mouse model. The results therefore provide no evidence that HDGF has a transforming capacity in tumor development. Our results in combination with previous findings point to a possible role in cell differentiation and suggest that HDGF promotes tumor progression after secondary upregulation and may represent another protein fitting into the concept of non-oncogene addiction of tumor tissue

Route of challenge is critical in determining the clinical outcome of infection with a very virulent oncogenic herpesvirus, Marek's disease virus.

OpenAIRE

Butter , Colin; Staines , Karen; Baaten , Bas; Smith , Lorraine; Davison , Fred

2007-01-01

Abstract Susceptible (Line 7) and resistant (Line 6) white leghorn chickens were infected with a very virulent Marek?s Disease Virus, RB1B, by either the intra-abdominal or intra-tracheal routes. Birds infected by the intra-tracheal route had earlier, higher or more sustained blood, spleen and lung viral loads, than those infected by the intra-peritoneal route. Line 7 birds had higher viral loads than Line 6 birds infected by the same route. Clinical outcomes reflected these ...

Mapping the history and current situation of research on John Cunningham virus – a bibliometric analysis

Directory of Open Access Journals (Sweden)

Guan Yi-fu

2009-03-01

Full Text Available Abstract Background John Cunningham virus (JCV constitutes a family of polyoma viruses, which plays important roles in the progressive multifocal leukoencephalopathy (PML and tumorigenesis. However, no bibliometric investigation has been reported to guide the researchers and potential readers. Methods Papers were collected from database Sci-expanded and Pubmed until May 22, 2008. The highly-productive authors, institutes and countries, highly-cited authors and journals were ranked. The highly-cited articles were subjected to co-citation and chronological analysis with highly-frequent MeSH words for co-occurrence analysis. Results Until now, 1785 articles about JCV were indexed in Sci-expanded and 1506 in Pubmed. The main document type was original article. USA, Japan and Italy were the largest three producers about JCV. Temple University published 128 papers and ranked the top, followed by University of Tokyo. Khalili K and Yogo Y became the core authors due to more than 20 documents produced. Journal of Neurovirology published more than 15 papers and ranked the top. Padgett BL and Berger JR were the first two highly-cited authors. Journal of Virology and Journal of Neurovirology respectively ranked to the first two highly-cited journals. These top highly-cited articles were divided into 5 aspects: (1 The correlation between JC virus and tumors; (2 Causal correlation of JCV with PML; (3 Polyoma virus infection and its related diseases in renal-allograft recipients; (4 Detection of JCV antibody, oncogene and its encoding protein; (5 Genetics and molecular biology of JCV. The MeSH/subheadings were classified into five groups: (1 JCV and virus infectious diseases; (2 JCV pathogenicity and pathological appearance of PML; (3 JCV isolation and detection; (4 Immunology of JCV and PML; (5 JCV genetics and tumors. Conclusion JCV investigation mainly focused on its isolation and detection, as well as its correlation with PML and tumors. Establishment of

Oncogenic Signaling by Leukemia-Associated Mutant Cbl Proteins

Science.gov (United States)

Nadeau, Scott; An, Wei; Palermo, Nick; Feng, Dan; Ahmad, Gulzar; Dong, Lin; Borgstahl, Gloria E. O.; Natarajan, Amarnath; Naramura, Mayumi; Band, Vimla; Band, Hamid

2013-01-01

Members of the Cbl protein family (Cbl, Cbl-b, and Cbl-c) are E3 ubiquitin ligases that have emerged as critical negative regulators of protein tyrosine kinase (PTK) signaling. This function reflects their ability to directly interact with activated PTKs and to target them as well as their associated signaling components for ubiquitination. Given the critical roles of PTK signaling in driving oncogenesis, recent studies in animal models and genetic analyses in human cancer have firmly established that Cbl proteins function as tumor suppressors. Missense mutations or small in-frame deletions within the regions of Cbl protein that are essential for its E3 activity have been identified in nearly 5% of leukemia patients with myelodysplastic/myeloproliferative disorders. Based on evidence from cell culture studies, in vivo models and clinical data, we discuss the potential signaling mechanisms of mutant Cbl-driven oncogenesis. Mechanistic insights into oncogenic Cbl mutants and associated animal models are likely to enhance our understanding of normal hematopoietic stem cell homeostasis and provide avenues for targeted therapy of mutant Cbl-driven cancers. PMID:23997989

Human papilloma virus positive oropharyngeal squamous cell carcinoma: a growing epidemic.

Science.gov (United States)

Panwar, Aru; Batra, Rishi; Lydiatt, William M; Ganti, Apar Kishor

2014-03-01

The incidence of oropharyngeal squamous cell carcinoma (OPSCC) is increasing despite a decrease in tobacco use. Almost 20-30% of patients with OPSCC do not have the traditional risk factors of smoking and alcohol use and in a vast majority of these patients, the human papilloma virus (HPV) appears to drive the malignant transformation. HPV induced malignant transformation is attributed to two viral oncogenes and their non-structural protein products (E6 and E7). These two proteins appear to affect carcinogenesis by their inhibitory effects on p53 and retinoblastoma proteins (Rb). Patients with HPV mediated OPSCC seem to have a better prognosis compared to their non-HPV counterparts. However, in the absence of strong evidence, standard of care at this time for OPSCC does not differ based on HPV status. Current research is focused on the role of de-escalation of treatment and elucidation of prognostic markers in this unique population. This review focuses on the pathogenesis of HPV mediated OPSCC and details the current evidence in the management of these patients. Published by Elsevier Ltd.

Lack of evidence for KRAS oncogenic mutations in triple-negative breast cancer

International Nuclear Information System (INIS)

Sánchez-Muñoz, Alfonso; Gallego, Elena; Luque, Vanessa de; Pérez-Rivas, Luís G; Vicioso, Luís; Ribelles, Nuria; Lozano, José; Alba, Emilio

2010-01-01

Mutational analysis of the KRAS gene has recently been established as a complementary in vitro diagnostic tool for the identification of patients with colorectal cancer who will not benefit from anti-epidermal growth factor receptor (EGFR) therapies. Assessment of the mutation status of KRAS might also be of potential relevance in other EGFR-overexpressing tumors, such as those occurring in breast cancer. Although KRAS is mutated in only a minor fraction of breast tumors (5%), about 60% of the basal-like subtype express EGFR and, therefore could be targeted by EGFR inhibitors. We aimed to study the mutation frequency of KRAS in that subtype of breast tumors to provide a molecular basis for the evaluation of anti-EGFR therapies. Total, genomic DNA was obtained from a group of 35 formalin-fixed paraffin-embedded, triple-negative breast tumor samples. Among these, 77.1% (27/35) were defined as basal-like by immunostaining specific for the established surrogate markers cytokeratin (CK) 5/6 and/or EGFR. KRAS mutational status was determined in the purified DNA samples by Real Time (RT)-PCR using primers specific for the detection of wild-type KRAS or the following seven oncogenic somatic mutations: Gly12Ala, Gly12Asp, Gly12Arg, Gly12Cys, Gly12Ser, Gly12Val and Gly13Asp. We found no evidence of KRAS oncogenic mutations in all analyzed tumors. This study indicates that KRAS mutations are very infrequent in triple-negative breast tumors and that EGFR inhibitors may be of potential benefit in the treatment of basal-like breast tumors, which overexpress EGFR in about 60% of all cases

Inhibition of the H3K9 methyltransferase G9A attenuates oncogenicity and activates the hypoxia signaling pathway.

Directory of Open Access Journals (Sweden)

Jolene Caifeng Ho

Full Text Available Epigenetic mechanisms play important roles in the regulation of tumorigenesis, and hypoxia-induced epigenetic changes may be critical for the adaptation of cancer cells to the hypoxic microenvironment of solid tumors. Previously, we showed that loss-of-function of the hypoxia-regulated H3K9 methyltransferase G9A attenuates tumor growth. However, the mechanisms by which blockade of G9A leads to a tumor suppressive effect remain poorly understood. We show that G9A is highly expressed in breast cancer and is associated with poor patient prognosis, where it may function as a potent oncogenic driver. In agreement with this, G9A inhibition by the small molecule inhibitor, BIX-01294, leads to increased cell death and impaired cell migration, cell cycle and anchorage-independent growth. Interestingly, whole transcriptome analysis revealed that genes involved in diverse cancer cell functions become hypoxia-responsive upon G9A inhibition. This was accompanied by the upregulation of the hypoxia inducible factors HIF1α and HIF2α during BIX-01294 treatment even in normoxia that may facilitate the tumor suppressive effects of BIX-01294. HIF inhibition was able to reverse some of the transcriptional changes induced by BIX-01294 in hypoxia, indicating that the HIFs may be important drivers of these derepressed target genes. Therefore, we show that G9A is a key mediator of oncogenic processes in breast cancer cells and G9A inhibition by BIX-01294 can successfully attenuate oncogenicity even in hypoxia.

Inhibition of the H3K9 methyltransferase G9A attenuates oncogenicity and activates the hypoxia signaling pathway

Science.gov (United States)

Ho, Jolene Caifeng; Abdullah, Lissa Nurrul; Pang, Qing You; Jha, Sudhakar; Chow, Edward Kai-Hua; Yang, Henry; Kato, Hiroyuki; Ueda, Jun

2017-01-01

Epigenetic mechanisms play important roles in the regulation of tumorigenesis, and hypoxia-induced epigenetic changes may be critical for the adaptation of cancer cells to the hypoxic microenvironment of solid tumors. Previously, we showed that loss-of-function of the hypoxia-regulated H3K9 methyltransferase G9A attenuates tumor growth. However, the mechanisms by which blockade of G9A leads to a tumor suppressive effect remain poorly understood. We show that G9A is highly expressed in breast cancer and is associated with poor patient prognosis, where it may function as a potent oncogenic driver. In agreement with this, G9A inhibition by the small molecule inhibitor, BIX-01294, leads to increased cell death and impaired cell migration, cell cycle and anchorage-independent growth. Interestingly, whole transcriptome analysis revealed that genes involved in diverse cancer cell functions become hypoxia-responsive upon G9A inhibition. This was accompanied by the upregulation of the hypoxia inducible factors HIF1α and HIF2α during BIX-01294 treatment even in normoxia that may facilitate the tumor suppressive effects of BIX-01294. HIF inhibition was able to reverse some of the transcriptional changes induced by BIX-01294 in hypoxia, indicating that the HIFs may be important drivers of these derepressed target genes. Therefore, we show that G9A is a key mediator of oncogenic processes in breast cancer cells and G9A inhibition by BIX-01294 can successfully attenuate oncogenicity even in hypoxia. PMID:29145444

Advances in cancer research

Energy Technology Data Exchange (ETDEWEB)

Klein, G. (Dept. of Tumor Biology, Karolinska Institute, Stockholm, (SE)) Weinhouse, S. (Fels Research Institute, Temples Univ. Medical School, Philadelphia, PA (US))

1987-01-01

This book contains the following 10 chapters: Interactions of Retroviral Oncogenes with the Differentiation Program of Myogenic Cells; The fos Oncogene; Role of the abl Oncogene in Chronic Myelogenous Leukemia; The Epstein-Barr Virus and the Immune System; The Use of Cell Markers in the Study of Human Hematopoietic Neoplasia; Multistage Model of Natural Killer Cell-Mediated Cytotoxicity Involving NKCF as Soluble Cytotoxic Mediators; Shedding of Human Tumor-Associated Antigens in Vitro and in Vivo; New Classes of Tumor Promoters: Teleocidin, Aplysiatoxin and Palytoxin; Anticarcinogenic Action of Protease Inhibitors; and On the Epidemiology of Oral Contraceptives and Disease.

Clinical Implication of Elevated Human Cervical Cancer Oncogene-1 Expression in Esophageal Squamous Cell Carcinoma

OpenAIRE

Liu, Ying; Li, Ke; Ren, Zhonghai; Li, Shenglei; Zhang, Hongyan; Fan, Qingxia

2012-01-01

The human cervical cancer oncogene 1 (HCCR-1), a novel human oncoprotein, has been shown to be upregulated in various human tumors and plays a critical role in tumorigenesis and tumor progression. Here, the authors investigated HCCR-1 level in esophageal squamous cell carcinoma (ESCC) tissues and assessed the correlation between HCCR-1 level and prognosis of the patients with ESCC. HCCR-1 levels were investigated by immunohistochemistry, in situ hybridization, real-time quantit...

The Criteria to Confirm the Role of Epstein-Barr Virus in Nasopharyngeal Carcinoma Initiation

Directory of Open Access Journals (Sweden)

Ai-Di Gu

2012-10-01

Full Text Available Epstein-Barr virus (EBV is associated with nasopharyngeal carcinoma (NPC, but it remains obscure whether EBV is a viral cause of, or only an accompaniment of, NPC. We will discuss the accumulated evidence pointing to the relationship between EBV infection and NPC initiation from epidemiologic, pathogenic, molecular oncogenic, and experimental animal studies. We believe that convincing evidence from these perspectives must be provided before we can ascertain the causal role of EBV infection in NPC. Specifically, (1 epidemiological studies should reveal EBV infection as a risk factor; (2 the introduction of EBV into an animal model should produce NPC; (3 in the animal model NPC, the main molecular event(s or the involved signaling pathway(s should be identical to that in human NPC; and (4 finally and most importantly, prevention of EBV infection or clearance of EBV from infected individuals must be able to reduce the incidence rate of NPC.

No evidence for the presence of Epstein-Barr virus in squamous cell carcinoma of the mobile tongue.

Science.gov (United States)

Wilms, Torben; Khan, Gulfaraz; Coates, Philip J; Sgaramella, Nicola; Fåhraeus, Robin; Hassani, Asma; Philip, Pretty S; Norberg Spaak, Lena; Califano, Luigi; Colella, Giuseppe; Olofsson, Katarina; Loizou, Christos; Franco, Renato; Nylander, Karin

2017-01-01

Squamous cell carcinoma of the head and neck (SCCHN) comprises a large group of cancers in the oral cavity and nasopharyngeal area that typically arise in older males in association with alcohol/tobacco usage. Within the oral cavity, the mobile tongue is the most common site for tumour development. The incidence of tongue squamous cell carcinoma (TSCC) is increasing in younger people, which has been suggested to associate with a viral aetiology. Two common human oncogenic viruses, human papilloma virus (HPV) and Epstein-Barr virus (EBV) are known causes of certain types of SCCHN, namely the oropharynx and nasopharynx, respectively. EBV infects most adults worldwide through oral transmission and establishes a latent infection, with sporadic productive viral replication and release of virus in the oral cavity throughout life. In view of the prevalence of EBV in the oral cavity and recent data indicating that it infects tongue epithelial cells and establishes latency, we examined 98 cases of primary squamous cell carcinoma of the mobile tongue and 15 cases of tonsillar squamous cell carcinoma for the presence of EBV-encoded RNAs (EBERs), EBV DNA and an EBV-encoded protein, EBNA-1. A commercially available in situ hybridisation kit targeting EBER transcripts (EBER-ISH) showed a positive signal in the cytoplasm and/or nuclei of tumour cells in 43% of TSCCs. However, application of control probes and RNase A digestion using in-house developed EBER-ISH showed identical EBER staining patterns, indicating non-specific signals. PCR analysis of the BamH1 W repeat sequences did not identify EBV genomes in tumour samples. Immunohistochemistry for EBNA-1 was also negative. These data exclude EBV as a potential player in TSCC in both old and young patients and highlight the importance of appropriate controls for EBER-ISH in investigating EBV in human diseases.

No evidence for the presence of Epstein-Barr virus in squamous cell carcinoma of the mobile tongue.

Directory of Open Access Journals (Sweden)

Torben Wilms

Full Text Available Squamous cell carcinoma of the head and neck (SCCHN comprises a large group of cancers in the oral cavity and nasopharyngeal area that typically arise in older males in association with alcohol/tobacco usage. Within the oral cavity, the mobile tongue is the most common site for tumour development. The incidence of tongue squamous cell carcinoma (TSCC is increasing in younger people, which has been suggested to associate with a viral aetiology. Two common human oncogenic viruses, human papilloma virus (HPV and Epstein-Barr virus (EBV are known causes of certain types of SCCHN, namely the oropharynx and nasopharynx, respectively. EBV infects most adults worldwide through oral transmission and establishes a latent infection, with sporadic productive viral replication and release of virus in the oral cavity throughout life. In view of the prevalence of EBV in the oral cavity and recent data indicating that it infects tongue epithelial cells and establishes latency, we examined 98 cases of primary squamous cell carcinoma of the mobile tongue and 15 cases of tonsillar squamous cell carcinoma for the presence of EBV-encoded RNAs (EBERs, EBV DNA and an EBV-encoded protein, EBNA-1. A commercially available in situ hybridisation kit targeting EBER transcripts (EBER-ISH showed a positive signal in the cytoplasm and/or nuclei of tumour cells in 43% of TSCCs. However, application of control probes and RNase A digestion using in-house developed EBER-ISH showed identical EBER staining patterns, indicating non-specific signals. PCR analysis of the BamH1 W repeat sequences did not identify EBV genomes in tumour samples. Immunohistochemistry for EBNA-1 was also negative. These data exclude EBV as a potential player in TSCC in both old and young patients and highlight the importance of appropriate controls for EBER-ISH in investigating EBV in human diseases.

No evidence for the presence of Epstein-Barr virus in squamous cell carcinoma of the mobile tongue

Science.gov (United States)

Wilms, Torben; Khan, Gulfaraz; Coates, Philip J.; Sgaramella, Nicola; Fåhraeus, Robin; Hassani, Asma; Philip, Pretty S.; Norberg Spaak, Lena; Califano, Luigi; Colella, Giuseppe; Olofsson, Katarina; Loizou, Christos; Franco, Renato

2017-01-01

Squamous cell carcinoma of the head and neck (SCCHN) comprises a large group of cancers in the oral cavity and nasopharyngeal area that typically arise in older males in association with alcohol/tobacco usage. Within the oral cavity, the mobile tongue is the most common site for tumour development. The incidence of tongue squamous cell carcinoma (TSCC) is increasing in younger people, which has been suggested to associate with a viral aetiology. Two common human oncogenic viruses, human papilloma virus (HPV) and Epstein-Barr virus (EBV) are known causes of certain types of SCCHN, namely the oropharynx and nasopharynx, respectively. EBV infects most adults worldwide through oral transmission and establishes a latent infection, with sporadic productive viral replication and release of virus in the oral cavity throughout life. In view of the prevalence of EBV in the oral cavity and recent data indicating that it infects tongue epithelial cells and establishes latency, we examined 98 cases of primary squamous cell carcinoma of the mobile tongue and 15 cases of tonsillar squamous cell carcinoma for the presence of EBV-encoded RNAs (EBERs), EBV DNA and an EBV-encoded protein, EBNA-1. A commercially available in situ hybridisation kit targeting EBER transcripts (EBER-ISH) showed a positive signal in the cytoplasm and/or nuclei of tumour cells in 43% of TSCCs. However, application of control probes and RNase A digestion using in-house developed EBER-ISH showed identical EBER staining patterns, indicating non-specific signals. PCR analysis of the BamH1 W repeat sequences did not identify EBV genomes in tumour samples. Immunohistochemistry for EBNA-1 was also negative. These data exclude EBV as a potential player in TSCC in both old and young patients and highlight the importance of appropriate controls for EBER-ISH in investigating EBV in human diseases. PMID:28926591

Characterization of Two Novel Oncogenic Pathways Collaborating With Loss of P53 or Activated Neu in Mouse Models of Breast Cancer

National Research Council Canada - National Science Library

Lu, Jianrong; Leder, Philip

2005-01-01

Cancer develops through accumulation of multiple genetic mutations. Loss of tumor suppressor gene p53 and activation of oncogene Neu/ErbB2 are among the most frequent genetic alterations in human breast cancer...

Melanoma Suppressor Functions of the Carcinoma Oncogene FOXQ1

Directory of Open Access Journals (Sweden)

Archis Bagati

2017-09-01

Full Text Available Lineage-specific regulation of tumor progression by the same transcription factor is understudied. We find that levels of the FOXQ1 transcription factor, an oncogene in carcinomas, are decreased during melanoma progression. Moreover, in contrast to carcinomas, FOXQ1 suppresses epithelial-to-mesenchymal transition, invasion, and metastasis in melanoma cells. We find that these lineage-specific functions of FOXQ1 largely depend on its ability to activate (in carcinomas or repress (in melanoma transcription of the N-cadherin gene (CDH2. We demonstrate that FOXQ1 interacts with nuclear β-catenin and TLE proteins, and the β-catenin/TLE ratio, which is higher in carcinoma than melanoma cells, determines the effect of FOXQ1 on CDH2 transcription. Accordingly, other FOXQ1-dependent phenotypes can be manipulated by altering nuclear β-catenin or TLE proteins levels. Our data identify FOXQ1 as a melanoma suppressor and establish a mechanism underlying its inverse lineage-specific transcriptional regulation of transformed phenotypes.

Oncogenic osteomalacia: a clinicopathologic study of 17 bone lesions.

Science.gov (United States)

Park, Y. K.; Unni, K. K.; Beabout, J. W.; Hodgson, S. F.

1994-01-01

Oncogenic osteomalacia is an unusual and rare clinicopathologic syndrome characterized by mesenchymal tumors that apparently produce osteomalacia and biochemical abnormalities consisting of hypophosphatemia, normocalcemia, and increased levels of alkaline phosphatase. We collected from the Mayo Clinic files and from our consultation files the records for 17 cases of osteomalacia associated with bone lesions. There were five cases of fibrous dysplasia, three of hemangiopericytoma, and two of phosphaturic mesenchymal tumor. There was one case each of osteosarcoma, chondroblastoma, chondromyxoid fibroma, malignant fibrous histiocytoma, giant cell tumor, metaphyseal fibrous defect, and hemangioma. In this study we can figure out that the most common characteristic histologic features of our cases were hemangiopericytomatous vascular proliferation, fine lace-like stromal calcification, and stromal giant cells. In most of the cases, the clinical and biochemical symptoms and signs resolved soon after complete resection of the lesion. When the lesion recurred or metastasized, the symptoms and signs also recurred. PMID:7848576

GTP Binding and Oncogenic Mutations May Attenuate Hypervariable Region (HVR)-Catalytic Domain Interactions in Small GTPase K-Ras4B, Exposing the Effector Binding Site*

Science.gov (United States)

Lu, Shaoyong; Banerjee, Avik; Jang, Hyunbum; Zhang, Jian; Gaponenko, Vadim; Nussinov, Ruth

2015-01-01

K-Ras4B, a frequently mutated oncogene in cancer, plays an essential role in cell growth, differentiation, and survival. Its C-terminal membrane-associated hypervariable region (HVR) is required for full biological activity. In the active GTP-bound state, the HVR interacts with acidic plasma membrane (PM) headgroups, whereas the farnesyl anchors in the membrane; in the inactive GDP-bound state, the HVR may interact with both the PM and the catalytic domain at the effector binding region, obstructing signaling and nucleotide exchange. Here, using molecular dynamics simulations and NMR, we aim to figure out the effects of nucleotides (GTP and GDP) and frequent (G12C, G12D, G12V, G13D, and Q61H) and infrequent (E37K and R164Q) oncogenic mutations on full-length K-Ras4B. The mutations are away from or directly at the HVR switch I/effector binding site. Our results suggest that full-length wild-type GDP-bound K-Ras4B (K-Ras4BWT-GDP) is in an intrinsically autoinhibited state via tight HVR-catalytic domain interactions. The looser association in K-Ras4BWT-GTP may release the HVR. Some of the oncogenic mutations weaken the HVR-catalytic domain association in the K-Ras4B-GDP/-GTP bound states, which may facilitate the HVR disassociation in a nucleotide-independent manner, thereby up-regulating oncogenic Ras signaling. Thus, our results suggest that mutations can exert their effects in more than one way, abolishing GTP hydrolysis and facilitating effector binding. PMID:26453300

Mitochondrial clearance by the STK38 kinase supports oncogenic Ras-induced cell transformation

Science.gov (United States)

Bettoun, Audrey; Surdez, Didier; Vallerand, David; Gundogdu, Ramazan; Sharif, Ahmad A.D.; Gomez, Marta; Cascone, Ilaria; Meunier, Brigitte; White, Michael A.; Codogno, Patrice; Parrini, Maria Carla; Camonis, Jacques H.; Hergovich, Alexander

2016-01-01

Oncogenic Ras signalling occurs frequently in many human cancers. However, no effective targeted therapies are currently available to treat patients suffering from Ras-driven tumours. Therefore, it is imperative to identify downstream effectors of Ras signalling that potentially represent promising new therapeutic options. Particularly, considering that autophagy inhibition can impair the survival of Ras-transformed cells in tissue culture and mouse models, an understanding of factors regulating the balance between autophagy and apoptosis in Ras-transformed human cells is needed. Here, we report critical roles of the STK38 protein kinase in oncogenic Ras transformation. STK38 knockdown impaired anoikis resistance, anchorage-independent soft agar growth, and in vivo xenograft growth of Ras-transformed human cells. Mechanistically, STK38 supports Ras-driven transformation through promoting detachment-induced autophagy. Even more importantly, upon cell detachment STK38 is required to sustain the removal of damaged mitochondria by mitophagy, a selective autophagic process, to prevent excessive mitochondrial reactive oxygen species production that can negatively affect cancer cell survival. Significantly, knockdown of PINK1 or Parkin, two positive regulators of mitophagy, also impaired anoikis resistance and anchorage-independent growth of Ras-transformed human cells, while knockdown of USP30, a negative regulator of PINK1/Parkin-mediated mitophagy, restored anchorage-independent growth of STK38-depleted Ras-transformed human cells. Therefore, our findings collectively reveal novel molecular players that determine whether Ras-transformed human cells die or survive upon cell detachment, which potentially could be exploited for the development of novel strategies to target Ras-transformed cells. PMID:27283898

Relationship of ultrasonic shear wave velocity with oncogene and tumor suppressor gene expression in primary liver cancer lesions as well as angiogenesis factor contents

Directory of Open Access Journals (Sweden)

Xing Yin1

2017-06-01

Full Text Available Objective: To discuss the relationship of ultrasonic shear wave velocity (SWV with oncogene and tumor suppressor gene expression in primary liver cancer lesions as well as angiogenesis factor contents. Methods: 100 patients with primary liver cancer who underwent surgical treatment in our hospital between March 2014 and September 2016 were collected as observation group, and 50 healthy subjects who received physical examination in our hospital during the same period were collected as normal control group. The ultrasonic SWV levels of two groups of subjects were measured before the operation, and the observation groups were further divided into high SWV group and low SWV group, 50 cases in each group. Intraoperative tumor tissue samples were kept and fluorescence quantitative PCR was used to determine the mRNA expression of oncogenes and tumor suppressor genes. Enzymelinked immunosorbent assay was used to determine serum contents of angiogenesis factors in observation group before operation. Results: Hepatic ultrasonic SWV level in observation group was significantly higher than that in normal control group; proto-oncogene CK, Ki67, Gly-3, Survivin and Pokemon mRNA expression in tumor tissue of high SWV group were higher than those of low SWV group while tumor suppressor genes Tg737, p16, p27, PTEN and runx3 mRNA expression were lower than those of low SWV group; serum angiogenesis factors VEGF, MMP-9 and IGF-1R contents were higher than those in low SWV group. Conclusion: The hepatic ultrasonic SWV level increases in patients with primary liver cancer, and the SWV level is directly correlated with oncogene and tumor suppressor gene expression as well as angiogenesis factor contents.

FOXP3 is a novel transcriptional repressor for the breast cancer oncogene SKP2

OpenAIRE

Zuo, Tao; Liu, Runhua; Zhang, Huiming; Chang, Xing; Liu, Yan; Wang, Lizhong; Zheng, Pan; Liu, Yang

2007-01-01

S-phase kinase-associated protein 2 (SKP2) is a component of the E3 ubiquitin ligase SKP1-Cul1-Fbox complex. Overexpression of SKP2 results in cell cycle dysregulation and carcinogenesis; however, the genetic lesions that cause this upregulation are poorly understood. We recently demonstrated that forkhead box P3 (FOXP3) is an X-linked breast cancer suppressor and an important repressor of the oncogene ERBB2/HER2. Since FOXP3 suppresses tumor growth regardless of whether the tumors overexpres...

Role of cannabinoid receptor CB2 in HER2 pro-oncogenic signaling in breast cancer.

Science.gov (United States)

Pérez-Gómez, Eduardo; Andradas, Clara; Blasco-Benito, Sandra; Caffarel, María M; García-Taboada, Elena; Villa-Morales, María; Moreno, Estefanía; Hamann, Sigrid; Martín-Villar, Ester; Flores, Juana M; Wenners, Antonia; Alkatout, Ibrahim; Klapper, Wolfram; Röcken, Christoph; Bronsert, Peter; Stickeler, Elmar; Staebler, Annette; Bauer, Maret; Arnold, Norbert; Soriano, Joaquim; Pérez-Martínez, Manuel; Megías, Diego; Moreno-Bueno, Gema; Ortega-Gutiérrez, Silvia; Artola, Marta; Vázquez-Villa, Henar; Quintanilla, Miguel; Fernández-Piqueras, José; Canela, Enric I; McCormick, Peter J; Guzmán, Manuel; Sánchez, Cristina

2015-06-01

Pharmacological activation of cannabinoid receptors elicits antitumoral responses in different cancer models. However, the biological role of these receptors in tumor physio-pathology is still unknown. We analyzed CB2 cannabinoid receptor protein expression in two series of 166 and 483 breast tumor samples operated in the University Hospitals of Kiel, Tübingen, and Freiburg between 1997 and 2010 and CB2 mRNA expression in previously published DNA microarray datasets. The role of CB2 in oncogenesis was studied by generating a mouse line that expresses the human V-Erb-B2 Avian Erythroblastic Leukemia Viral Oncogene Homolog 2 (HER2) rat ortholog (neu) and lacks CB2 and by a variety of biochemical and cell biology approaches in human breast cancer cells in culture and in vivo, upon modulation of CB2 expression by si/shRNAs and overexpression plasmids. CB2-HER2 molecular interaction was studied by colocalization, coimmunoprecipitation, and proximity ligation assays. Statistical tests were two-sided. We show an association between elevated CB2 expression in HER2+ breast tumors and poor patient prognosis (decreased overall survival, hazard ratio [HR] = 0.29, 95% confidence interval [CI] = 0.09 to 0.71, P = .009) and higher probability to suffer local recurrence (HR = 0.09, 95% CI = 0.049 to 0.54, P = .003) and to develop distant metastases (HR = 0.33, 95% CI = 0.13 to 0.75, P = .009). We also demonstrate that genetic inactivation of CB2 impairs tumor generation and progression in MMTV-neu mice. Moreover, we show that HER2 upregulates CB2 expression by activating the transcription factor ELK1 via the ERK cascade and that an increased CB2 expression activates the HER2 pro-oncogenic signaling at the level of the tyrosine kinase c-SRC. Finally, we show HER2 and CB2 form heteromers in cancer cells. Our findings reveal an unprecedented role of CB2 as a pivotal regulator of HER2 pro-oncogenic signaling in breast cancer, and they suggest that CB2 may be a biomarker with

Direct Targeting of β-Catenin by a Small Molecule Stimulates Proteasomal Degradation and Suppresses Oncogenic Wnt/β-Catenin Signaling

Directory of Open Access Journals (Sweden)

So-Young Hwang

2016-06-01

Full Text Available The Wnt/β-catenin signaling pathway plays a major role in tissue homeostasis, and its dysregulation can lead to various human diseases. Aberrant activation of β-catenin is oncogenic and is a critical driver in the development and progression of human cancers. Despite the significant potential of targeting the oncogenic β-catenin pathway for cancer therapy, the development of specific inhibitors remains insufficient. Using a T cell factor (TCF-dependent luciferase-reporter system, we screened for small-molecule compounds that act against Wnt/β-catenin signaling and identified MSAB (methyl 3-{[(4-methylphenylsulfonyl]amino}benzoate as a selective inhibitor of Wnt/β-catenin signaling. MSAB shows potent anti-tumor effects selectively on Wnt-dependent cancer cells in vitro and in mouse cancer models. MSAB binds to β-catenin, promoting its degradation, and specifically downregulates Wnt/β-catenin target genes. Our findings might represent an effective therapeutic strategy for cancers addicted to the Wnt/β-catenin signaling pathway.

Evaluation of rapid diagnostic test kits for feline leukemia virus infection using samples from naturally infected cats

Directory of Open Access Journals (Sweden)

Jiayou Liu

2016-09-01

Full Text Available Objectives Feline leukemia virus (FeLV is a potentially life-threatening oncogenic retrovirus. The p27 viral core protein is produced by the virus in infected feline cells, is found in the cytoplasm in several blood cells and can be free in the serum and plasma. ELISA or particle-based immunoassay are commonly used to detect the presence of the p27 core protein in samples obtained from blood. The objective of this study was to compare the performance of several in-clinic tests: the SNAP Feline Triple Test (IDEXX Laboratories, the WITNESS FeLV-FIV Test (Zoetis and the VetScan Feline FeLV/FIV Rapid Test (Abaxis. Methods The sample population (100 positive, 105 negative samples consisted of serum and plasma samples submitted to IDEXX’s worldwide reference laboratory for feline retrovirus testing. Virus isolation and reverse transcriptase PCR results were not available and so samples were judged to be positive or negative based on the results of the ViraCHEK FeLV (Zoetis microtiter plate assay. Results The percentage of samples positive and negative for FeLV p27 antigen using the three in-clinic tests compared with the ViraCHEK method were as follows: IDEXX Feline Triple (positive 98.0%, negative 100%; Zoetis WITNESS (positive 79.0%, negative 97.1%; Abaxis VetScan (positive 73.0%, negative 97.1%. Conclusions and relevance The SNAP Feline Triple Test demonstrated a high level of agreement for FeLV-positive and FeLV-negative samples when assessed in this model. Results of FeLV assays can vary among tests.

Evaluation of rapid diagnostic test kits for feline leukemia virus infection using samples from naturally infected cats.

Science.gov (United States)

Liu, Jiayou; O'Connor, Thomas; Beall, Melissa; Chandrashekar, Ramaswamy; Lappin, Michael

2016-01-01

Feline leukemia virus (FeLV) is a potentially life-threatening oncogenic retrovirus. The p27 viral core protein is produced by the virus in infected feline cells, is found in the cytoplasm in several blood cells and can be free in the serum and plasma. ELISA or particle-based immunoassay are commonly used to detect the presence of the p27 core protein in samples obtained from blood. The objective of this study was to compare the performance of several in-clinic tests: the SNAP Feline Triple Test (IDEXX Laboratories), the WITNESS FeLV-FIV Test (Zoetis) and the VetScan Feline FeLV/FIV Rapid Test (Abaxis). The sample population (100 positive, 105 negative samples) consisted of serum and plasma samples submitted to IDEXX's worldwide reference laboratory for feline retrovirus testing. Virus isolation and reverse transcriptase PCR results were not available and so samples were judged to be positive or negative based on the results of the ViraCHEK FeLV (Zoetis) microtiter plate assay. The percentage of samples positive and negative for FeLV p27 antigen using the three in-clinic tests compared with the ViraCHEK method were as follows: IDEXX Feline Triple (positive 98.0%, negative 100%); Zoetis WITNESS (positive 79.0%, negative 97.1%); Abaxis VetScan (positive 73.0%, negative 97.1%). The SNAP Feline Triple Test demonstrated a high level of agreement for FeLV-positive and FeLV-negative samples when assessed in this model. Results of FeLV assays can vary among tests.

Role of GSK-3β in Regulation of Canonical Wnt/β-catenin Signaling and PI3-K/Akt Oncogenic Pathway in Colon Cancer.

Science.gov (United States)

Jain, Shelly; Ghanghas, Preety; Rana, Chandan; Sanyal, S N

2017-08-09

Non-steroidal anti-inflammatory drugs (NSAIDs) are emerging as novel chemopreventive agents because of their ability in blocking cellular proliferation, and thereby tumor development, and also by promoting apoptosis. GSK-3β, a serine threonine kinase and a negative regulator of the oncogenic Wnt/β-catenin signaling pathway, plays a critical role in the regulation of oncogenesis. Celecoxib and etoricoxib, the two cyclooxygenase-2 (COX-2) selective NSAIDs, and Diclofenac, a preferential COX-2 inhibitory NSAID, had shown uniformly the chemopreventive and anti-neoplastic effects in the early stage of colon cancer by promoting apoptosis as well as an over-expression of GSK-3β while down-regulating the PI3-K/Akt oncogenic pathway.

Proteome-wide analysis of protein abundance and turnover remodelling during oncogenic transformation of human breast epithelial cells [version 1; referees: 2 approved, 1 approved with reservations

Directory of Open Access Journals (Sweden)

Tony Ly

2018-05-01

Full Text Available Background: Viral oncogenes and mutated proto-oncogenes are potent drivers of cancer malignancy. Downstream of the oncogenic trigger are alterations in protein properties that give rise to cellular transformation and the acquisition of malignant cellular phenotypes. Developments in mass spectrometry enable large-scale, multidimensional characterisation of proteomes. Such techniques could provide an unprecedented, unbiased view of how oncogene activation remodels a human cell proteome. Methods: Using quantitative MS-based proteomics and cellular assays, we analysed how transformation induced by activating v-Src kinase remodels the proteome and cellular phenotypes of breast epithelial (MCF10A cells. SILAC MS was used to comprehensively characterise the MCF10A proteome and to measure v-Src-induced changes in protein abundance across seven time-points (1-72 hrs. We used pulse-SILAC MS (Boisvert et al., 2012, to compare protein synthesis and turnover in control and transformed cells. Follow-on experiments employed a combination of cellular and functional assays to characterise the roles of selected Src-responsive proteins. Results: Src-induced transformation changed the expression and/or turnover levels of ~3% of proteins, affecting ~1.5% of the total protein molecules in the cell. Transformation increased the average rate of proteome turnover and disrupted protein homeostasis. We identify distinct classes of protein kinetics in response to Src activation. We demonstrate that members of the polycomb repressive complex 1 (PRC1 are important regulators of invasion and migration in MCF10A cells. Many Src-regulated proteins are present in low abundance and some are regulated post-transcriptionally. The signature of Src-responsive proteins is highly predictive of poor patient survival across multiple cancer types. Open access to search and interactively explore all these proteomic data is provided via the EPD database (www.peptracker.com/epd. Conclusions

Antineoplastic Effects of siRNA against TMPRSS2-ERG Junction Oncogene in Prostate Cancer.

Directory of Open Access Journals (Sweden)

Giorgia Urbinati

Full Text Available TMPRSS2-ERG junction oncogene is present in more than 50% of patients with prostate cancer and its expression is frequently associated with poor prognosis. Our aim is to achieve gene knockdown by siRNA TMPRSS2-ERG and then to assess the biological consequences of this inhibition. First, we designed siRNAs against the two TMPRSS2-ERG fusion variants (III and IV, most frequently identified in patients' biopsies. Two of the five siRNAs tested were found to efficiently inhibit mRNA of both TMPRSS2-ERG variants and to decrease ERG protein expression. Microarray analysis further confirmed ERG inhibition by both siRNAs TMPRSS2-ERG and revealed one common down-regulated gene, ADRA2A, involved in cell proliferation and migration. The siRNA against TMPRSS2-ERG fusion variant IV showed the highest anti-proliferative effects: Significantly decreased cell viability, increased cleaved caspase-3 and inhibited a cluster of anti-apoptotic proteins. To propose a concrete therapeutic approach, siRNA TMPRSS2-ERG IV was conjugated to squalene, which can self-organize as nanoparticles in water. The nanoparticles of siRNA TMPRSS2-ERG-squalene injected intravenously in SCID mice reduced growth of VCaP xenografted tumours, inhibited oncoprotein expression and partially restored differentiation (decrease in Ki67. In conclusion, this study offers a new prospect of treatment for prostate cancer based on siRNA-squalene nanoparticles targeting TMPRSS2-ERG junction oncogene.

FOXP3 is a novel transcriptional repressor for the breast cancer oncogene SKP2.

Science.gov (United States)

Zuo, Tao; Liu, Runhua; Zhang, Huiming; Chang, Xing; Liu, Yan; Wang, Lizhong; Zheng, Pan; Liu, Yang

2007-12-01

S-phase kinase-associated protein 2 (SKP2) is a component of the E3 ubiquitin ligase SKP1-Cul1-Fbox complex. Overexpression of SKP2 results in cell cycle dysregulation and carcinogenesis; however, the genetic lesions that cause this upregulation are poorly understood. We recently demonstrated that forkhead box P3 (FOXP3) is an X-linked breast cancer suppressor and an important repressor of the oncogene ERBB2/HER2. Since FOXP3 suppresses tumor growth regardless of whether the tumors overexpress ERBB2/HER2, additional FOXP3 targets may be involved in its tumor suppressor activity. Here, we show that mammary carcinomas from mice heterozygous for a Foxp3 mutation exhibited increased Skp2 expression. Ectopic expression of FOXP3 in mouse mammary cancer cells repressed SKP2 expression with a corresponding increase in p27 and polyploidy. Conversely, siRNA silencing of the FOXP3 gene in human mammary epithelial cells increased SKP2 expression. We also show that Foxp3 directly interacted with and repressed the Skp2 promoter. Moreover, the analysis of over 200 primary breast cancer samples revealed an inverse correlation between FOXP3 and SKP2 levels. Finally, we demonstrated that downregulation of SKP2 was critical for FOXP3-mediated growth inhibition in breast cancer cells that do not overexpress ERBB2/HER2. Our data provide genetic, biochemical, and functional evidence that FOXP3 is a novel transcriptional repressor for the oncogene SKP2.

Nairobi sheep disease virus/Ganjam virus.

Science.gov (United States)

M D, Baron; B, Holzer

2015-08-01

Nairobi sheep disease virus (NSDV) is a tick-borne virus which causes a severe disease in sheep and goats, and has been responsible for several outbreaks of disease in East Africa. The virus is also found in the Indian subcontinent, where it is known as Ganjam virus. The virus only spreads through the feeding of competent infected ticks, and is therefore limited in its geographic distribution by the distribution of those ticks, Rhipicephalus appendiculata in Africa and Haemaphysalis intermedia in India. Animals bred in endemic areas do not normally develop disease, and the impact is therefore primarily on animals being moved for trade or breeding purposes. The disease caused by NSDV has similarities to several other ruminant diseases, and laboratory diagnosis is necessary for confirmation. There are published methods for diagnosis based on polymerase chain reaction, for virus growth in cell culture and for other simple diagnostic tests, though none has been commercialised. There is no established vaccine against NSDV, although cell-culture attenuated strains have been developed which show promise and could be put into field trials if it were deemed necessary. The virus is closely related to Crimean-Congo haemorrhagic fever virus, and studies on NSDV may therefore be useful in understanding this important human pathogen.

Structural analysis of a hepatitis B virus genome integrated into chromosome 17p of a human hepatocellular carcinoma

International Nuclear Information System (INIS)

Zhou, Y.Z.; Slagle, B.L.; Donehower, L.A.; van Tuinen, P.; Ledbetter, D.H.; Butel, J.S.

1988-01-01

Hepatitis B virus (HBV) is clearly a factor in the development of hepatocellular carcinoma, but its mechanism of action remains obscure. One possibility is that the HBV integration event alters the expression of a nearby growth-regulatory cellular gene. A 9-kilobase (kb) DNA fragment containing an HBV insert plus flanking cellular sequences was cloned from a hepatoma specimen from Shanghai, People's Republic of China. Restriction mapping of the insert revealed a large inverted repeat structure consisting of both viral sequences (encompassing all of the core and pre-S regions and portions of the X and S genes) and at least 3 kb of unique cellular sequences. The virus-cell junction mapped 11 nucleotides from the DRI region, in a position within the HBV X gene and included in the cohesive overlap region. A probe generated from 1.0 kb of the flanking cellular DNA mapped the viral insert to chromosome 17 in the region designated 17p11.2-17p12, which is near the human proto-oncogene p53. Sequence data from a portion of the flanking cellular DNA revealed a stretch of approximately 70 base pairs that showed highly significant homology with a conserved region of a number of functional mammalian DNA, including the human autonomously replicating sequence 1 (ASRI)

EphrinB1 expression is dysregulated and promotes oncogenic signaling in medulloblastoma.

Science.gov (United States)

McKinney, Nicole; Yuan, Liangping; Zhang, Hongying; Liu, Jingbo; Cho, Yoon-Jae; Rushing, Elisabeth; Schniederjan, Matthew; MacDonald, Tobey J

2015-01-01

Eph receptors and ephrin ligands are master regulators of oncogenic signaling required for proliferation, migration, and metastasis. Yet, Eph/ephrin expression and activity in medulloblastoma (MB), the most common malignant brain tumor of childhood, remains poorly defined. We hypothesized that Eph/ephrins are differentially expressed by sonic hedgehog (SHH) and non-SHH MB and that specific members contribute to the aggressive phenotype. Affymetrix gene expression profiling of 29 childhood MB, separated into SHH (N = 11) and non-SHH (N = 18), was performed followed by protein validation of selected Eph/ephrins in another 60 MB and two MB cell lines (DAOY, D556). Functional assays were performed using MB cells overexpressing or deleted for selected ephrins. We found EPHB4 and EFNA4 almost exclusively expressed by SHH MB, whereas EPHA2, EPHA8, EFNA1 and EFNA3 are predominantly expressed by non-SHH MB. The remaining family members, except EFNB1, are ubiquitously expressed by over 70-90 % MB, irrespective of subgroup. EFNB1 is the only member differentially expressed by 28 % of SHH and non-SHH MB. Corresponding protein expression for EphB/ephrinB1 and B2 was validated in MB. Only ephrinB2 was also detected in fetal cerebellum, indicating that EphB/ephrinB1 expression is MB-specific. EphrinB1 immunopositivity localizes to tumor cells within MB with the highest proliferative index. EphrinB1 overexpression promotes EphB activation, alters F-actin distribution and morphology, decreases adhesion, and significantly promotes proliferation. Either silencing or overexpression of ephrinB1 impairs migration. These results indicate that EphrinB1 is uniquely dysregulated in MB and promotes oncogenic responses in MB cells, implicating ephrinB1 as a potential target.

Engineering CHO cells with an oncogenic KIT improves cells growth, resilience to stress, and productivity.

Science.gov (United States)

Mahameed, Mohamed; Tirosh, Boaz

2017-11-01

An optimized biomanufacturing process in mammalian cells is contingent on the ability of the producing cells to reach high viable cell densities. In addition, at the peak of growth, cells need to continue producing the biological entity at a consistent quality. Thus, engineering cells with robust growth performance and resilience to variable stress conditions is highly desirable. The tyrosine kinase receptor, KIT, plays a key role in cell differentiation and the survival of several immune cell types. Its oncogenic mutant, D816V, endows cells with high proliferation capacity, and resistance to kinase inhibitors. Importantly, this onco-KIT mutant when introduced into various cell types is arrested in the endoplasmic reticulum in a constitutively active form. Here, we investigated the effect of oncogenic D816V KIT on the performance of CHO-K1 cells under conventional tissue culture growth settings and when adapted, to shaking conditions. The onco-KIT promoted global protein synthesis, elevated the expression of a secretable transgene, enhanced proliferation, and improved the overall titers of a model glycoprotein. Moreover, the expression of the onco-KIT endowed the cells with a remarkable resistance to various stress conditions. Our data suggest that the introduction of onco-KIT can serve as a strategy for improving glycoprotein biomanufacturing. Biotechnol. Bioeng. 2017;114: 2560-2570. © 2017 Wiley Periodicals, Inc. © 2017 Wiley Periodicals, Inc.

Detection of E6/E7 HPV oncogene transcripts as biomarker of cervical intaepithelial displasia

Directory of Open Access Journals (Sweden)

Mauro Carcheri

2009-09-01

Full Text Available It is widely accepted that only persistent infection with high risk types of Human Papillomavirus (HPV HR is a significant risk factor for the development of an invasive squamous cervical cancer. The overexpression of viral oncogenes E6/E7 of HPV is considered a necessary process for incurring in a malignant phenotype.A HPV infection can be identified by detection of HPV DNA in biological samples, but the DNAbased tests cannot delineate between transient or persistent and potentially transforming infection. Instead there is many evidence to suggest that detection of HPV gene expression may constitute a more specific approach to highlight a clinically significant infection. Especially seems that the detection of E6/E7 transcripts can be usefully used for identify the women with a persistent HPV infection that will can induce a future cervical cancer. The aim of our study is to investigate if the detection of oncogenic viral gene activity by detecting transcripts of the E6 and E7 genes can be most usefull of HPV-DNA test in the triage of ASCUS or low grade cervical lesions. Our results confirm that HPV E6/E7 mRNA test can be considered a promising method to stratify HPV positive women for risk of future high-grade cervical lesions or cervical intaepithelial neoplasia.

Targeted Cancer Therapy: Vital Oncogenes and a New Molecular Genetic Paradigm for Cancer Initiation Progression and Treatment

Science.gov (United States)

Willis, Rudolph E.

2016-01-01

It has been declared repeatedly that cancer is a result of molecular genetic abnormalities. However, there has been no working model describing the specific functional consequences of the deranged genomic processes that result in the initiation and propagation of the cancer process during carcinogenesis. We no longer need to question whether or not cancer arises as a result of a molecular genetic defect within the cancer cell. The legitimate questions are: how and why? This article reviews the preeminent data on cancer molecular genetics and subsequently proposes that the sentinel event in cancer initiation is the aberrant production of fused transcription activators with new molecular properties within normal tissue stem cells. This results in the production of vital oncogenes with dysfunctional gene activation transcription properties, which leads to dysfunctional gene regulation, the aberrant activation of transduction pathways, chromosomal breakage, activation of driver oncogenes, reactivation of stem cell transduction pathways and the activation of genes that result in the hallmarks of cancer. Furthermore, a novel holistic molecular genetic model of cancer initiation and progression is presented along with a new paradigm for the approach to personalized targeted cancer therapy, clinical monitoring and cancer diagnosis. PMID:27649156

[Hybrids of human and monkey adenoviruses (adeno-adeno hybrids) that can reproduce in monkey cells: biological and molecular genetic peculiarities].

Science.gov (United States)

Grinenko, N F; Savitskaia, N V; Pashvykina, G V; Al'tshteĭn, A D

2003-06-01

A highly oncogenic monkey adenovirus SA7(C8) facilitates the reproduction of human adenovirus type 2 (Ad2) in monkey cells. Upon mixed infection of monkey cells with both viruses, these viruses recombine producing defective adeno-adeno hybrids Ad2C8 serologically identical to Ad2 and capable of assisting Ad2 to reproduce in monkey cells. Ad2C8 and Ad2 form an intercomplementary pair inseparable in monkey cells. Unlike oncogenic SA7(C8), Ad2C8 is a nononcogenic virus for hamsters but is able to induce tumor antigens of this virus (T and TSTA). Molecular genetic analysis of 68 clones of adeno-adeno hybrids revealed that the left part of their genome consists of Ad2 DNA, and the right part contains no less than 40% of the viral SA7(C8) genome where E2A, E3, and E4 genes are located. Apparently, the products of these genes contribute to the composition of adenoviral tumor antigens, while the E4 gene is involved in complementation of monkey and human adenoviruses and makes a contribution to host range determination of these viruses.

Colocalization of somatic and meiotic double strand breaks near the Myc oncogene on mouse chromosome 15.

Science.gov (United States)

Ng, Siemon H; Maas, Sarah A; Petkov, Petko M; Mills, Kevin D; Paigen, Kenneth

2009-10-01

Both somatic and meiotic recombinations involve the repair of DNA double strand breaks (DSBs) that occur at preferred locations in the genome. Improper repair of DSBs during either mitosis or meiosis can lead to mutations, chromosomal aberration such as translocations, cancer, and/or cell death. Currently, no model exists that explains the locations of either spontaneous somatic DSBs or programmed meiotic DSBs or relates them to each other. One common class of tumorigenic translocations arising from DSBs is chromosomal rearrangements near the Myc oncogene. Myc translocations have been associated with Burkitt lymphoma in humans, plasmacytoma in mice, and immunocytoma in rats. Comparing the locations of somatic and meiotic DSBs near the mouse Myc oncogene, we demonstrated that the placement of these DSBs is not random and that both events clustered in the same short discrete region of the genome. Our work shows that both somatic and meiotic DSBs tend to occur in proximity to each other within the Myc region, suggesting that they share common originating features. It is likely that some regions of the genome are more susceptible to both somatic and meiotic DSBs, and the locations of meiotic hotspots may be an indicator of genomic regions more susceptible to DNA damage. (c) 2009 Wiley-Liss, Inc.

Misoprostol-induced radioprotection of Syrian hamster embryo cells in utero from cell death and oncogenic transformation

International Nuclear Information System (INIS)

Miller, R.C.; LaNasa, P.; Hanson, W.R.

1994-01-01

Misoprostol, a PGE analog, is an effective radioprotector of murine intestine and hematopoietic and hair cell renewal systems. The radioprotective nature of misoprostol was extended to examine its ability to influence clonogenic cell survival and induction of oncogenic transformation in Syrian hamster embryo cells exposed to X rays in utero and assayed in vitro. Hamsters in their 12th day of pregnancy were injected subcutaneously with misoprostal, and 2 h later the pregnant hamsters were exposed to graded doses of X rays. Immediately after irradiation, hamsters were euthanized and embryonic tissue was explanted into culture dishes containing complete growth medium. After a 2-week incubation period, clongenic cell survival and morphologically transformed foci were determined. Survival of misoprostol-treated SHE cells was increased and yielded a dose reduction factor of 1.5 compared to SHE cells treated with X rays alone. In contrast, radiation-induced oncogenic transformation of misoprostol-treated cells was reduced by a factor of 20 compared to cells treated with X rays alone. These studies suggest that misoprostol not only protects normal tissues in vivo from acute radiation injury, but also protects cells, to a large extent, from injury leading to transforming events. 26 refs., 6 figs., 2 tabs

Complete coding sequence of the human raf oncogene and the corresponding structure of the c-raf-1 gene

Energy Technology Data Exchange (ETDEWEB)

Bonner, T I; Oppermann, H; Seeburg, P; Kerby, S B; Gunnell, M A; Young, A C; Rapp, U R

1986-01-24

The complete 648 amino acid sequence of the human raf oncogene was deduced from the 2977 nucleotide sequence of a fetal liver cDNA. The cDNA has been used to obtain clones which extend the human c-raf-1 locus by an additional 18.9 kb at the 5' end and contain all the remaining coding exons.

Oncogene alterations in carcinomas of the uterine cervix: overexpression of the epidermal growth factor receptor is associated with poor prognosis

NARCIS (Netherlands)

Kersemaekers, A. M.; Fleuren, G. J.; Kenter, G. G.; van den Broek, L. J.; Uljee, S. M.; Hermans, J.; van de Vijver, M. J.

1999-01-01

The involvement of human papillomavirus (HPV) in the development of carcinomas of the uterine cervix has been firmly established. However, other genetic alterations also play an important role in the pathogenesis of cervical cancer. Therefore, we have investigated the role of several (onco)genes in

Selective elimination of high constitutive activity or chemokine binding in the human herpesvirus 8 encoded seven transmembrane oncogene ORF74

DEFF Research Database (Denmark)

Rosenkilde, M M; Kledal, T N; Holst, Peter Johannes

2000-01-01

Open reading frame 74 (ORF74) encoded by human herpesvirus 8 is a highly constitutively active seven transmembrane (7TM) receptor stimulated by angiogenic chemokines, e.g. growth-related oncogene-alpha, and inhibited by angiostatic chemokines e.g. interferon-gamma-inducible protein. Transgenic mice...

Bacterionomics and vironomics in carcinogenesis

Directory of Open Access Journals (Sweden)

Pratiwi Sudarmono

2017-02-01

Full Text Available Virus and bacteria are microbes which are very common cause human infection. Most of the bacterial infection can be eradicated by antibiotics and infection symptoms disappear. But for virus infection, once infected, the virus will persistently stay in the host, even undergo not only a lytic cycle but also integrated into host genome. Nowadays, at least 6 virus type are consistently related to human cancer, such as EBV,HPV,HTLV,HBV,HCV,HKSV, and the new one Merkel Virus (MCV. Although not every infected people will get cancer, but around 20% of the whole cancer in human are caused by viral oncogene. Class one oncogenic bacterial is Helicobacter pylori. Infection with this bacteria can cause persistent gastro duodenal inflammation which cause some alteration in gastric cell growth into transformation. Expression of Cag gene and Vac gene and some expression of OMP protein usually link to gastric cancer. Molecular mechanisms of carcinogenesis for every virus which cause infection  is a very complex , which include several processes caused by cell transformation. Besides, other host and environmental factors are also play a significant role in cancer development. Some scientist put a Hallmark analysis as a model to quickly summarize what pathobiology process will happen and what gene or protein caused the process. The Hallmark analysis comprise of several process which may happen simultaneously because some of the Hallmark is caused by the same protein. The Hallmark consists of various virus strategies in oncogenesis such as promoting angiogenesis, avoiding immune destruction, genome instability and mutation, deregulating cellular energetic, resisting cell death, sustaining proliferative signaling, evading growth suppressors, enabling cellular immortality, promoting inflammation and activation metastasis. For example, infection by HPV, will cause low grade dysplasia which can continue to invasive cervical cancer. After host cell transformation, in

DIAGNOSTICS OF VIRUS PHYTOPATHOGENS FRUIT TREE PLUM POX VIRUS, PRUNUS NECROTIC RINGSPOT VIRUS AND PRUNUS DWARF VIRUS BY BIOLOGICAL AND MOLECULAR DIAGNOSTICS

Directory of Open Access Journals (Sweden)

Július Rozák

2013-02-01

Full Text Available The aim of this study was to determine the incidence of viral phytopathogen Plum pox virus, Prunus necrotic ringspot virus and Prunus dwarf virus in selected localities of Slovakia and diagnose them using a molecular and biological methods. Forty samples of fruit trees of the genus Prunus, twenty samples from intensive plantings and twenty samples from wild subject were analysed. Biological diagnostic by using biological indicators Prunus persica cv. GF 305, Prunus serrulata cv. Schirofugen and molecular diagnostic by mRT-PCR were applied. Five samples with Plum pox virus were infected. The two samples positive for Prunus necrotic ringspot virus and one sample for Prunus dwarf virus were confirmed. The two samples were found to be infected with two viruses Prunus necrotic ringspot virus and Prunus dwarf virus. This work focuses on two techniques, their application to the diagnosis of stone fruit viruses and their routinely used for sanitary and certification programmes.

GTP Binding and Oncogenic Mutations May Attenuate Hypervariable Region (HVR)-Catalytic Domain Interactions in Small GTPase K-Ras4B, Exposing the Effector Binding Site.

Science.gov (United States)

Lu, Shaoyong; Banerjee, Avik; Jang, Hyunbum; Zhang, Jian; Gaponenko, Vadim; Nussinov, Ruth

2015-11-27

K-Ras4B, a frequently mutated oncogene in cancer, plays an essential role in cell growth, differentiation, and survival. Its C-terminal membrane-associated hypervariable region (HVR) is required for full biological activity. In the active GTP-bound state, the HVR interacts with acidic plasma membrane (PM) headgroups, whereas the farnesyl anchors in the membrane; in the inactive GDP-bound state, the HVR may interact with both the PM and the catalytic domain at the effector binding region, obstructing signaling and nucleotide exchange. Here, using molecular dynamics simulations and NMR, we aim to figure out the effects of nucleotides (GTP and GDP) and frequent (G12C, G12D, G12V, G13D, and Q61H) and infrequent (E37K and R164Q) oncogenic mutations on full-length K-Ras4B. The mutations are away from or directly at the HVR switch I/effector binding site. Our results suggest that full-length wild-type GDP-bound K-Ras4B (K-Ras4B(WT)-GDP) is in an intrinsically autoinhibited state via tight HVR-catalytic domain interactions. The looser association in K-Ras4B(WT)-GTP may release the HVR. Some of the oncogenic mutations weaken the HVR-catalytic domain association in the K-Ras4B-GDP/-GTP bound states, which may facilitate the HVR disassociation in a nucleotide-independent manner, thereby up-regulating oncogenic Ras signaling. Thus, our results suggest that mutations can exert their effects in more than one way, abolishing GTP hydrolysis and facilitating effector binding. © 2015 by The American Society for Biochemistry and Molecular Biology, Inc.

The PDZ-binding motif of Yes-associated protein is required for its co-activation of TEAD-mediated CTGF transcription and oncogenic cell transforming activity

International Nuclear Information System (INIS)

Shimomura, Tadanori; Miyamura, Norio; Hata, Shoji; Miura, Ryota; Hirayama, Jun; Nishina, Hiroshi

2014-01-01

Highlights: •Loss of the PDZ-binding motif inhibits constitutively active YAP (5SA)-induced oncogenic cell transformation. •The PDZ-binding motif of YAP promotes its nuclear localization in cultured cells and mouse liver. •Loss of the PDZ-binding motif inhibits YAP (5SA)-induced CTGF transcription in cultured cells and mouse liver. -- Abstract: YAP is a transcriptional co-activator that acts downstream of the Hippo signaling pathway and regulates multiple cellular processes, including proliferation. Hippo pathway-dependent phosphorylation of YAP negatively regulates its function. Conversely, attenuation of Hippo-mediated phosphorylation of YAP increases its ability to stimulate proliferation and eventually induces oncogenic transformation. The C-terminus of YAP contains a highly conserved PDZ-binding motif that regulates YAP’s functions in multiple ways. However, to date, the importance of the PDZ-binding motif to the oncogenic cell transforming activity of YAP has not been determined. In this study, we disrupted the PDZ-binding motif in the YAP (5SA) protein, in which the sites normally targeted by Hippo pathway-dependent phosphorylation are mutated. We found that loss of the PDZ-binding motif significantly inhibited the oncogenic transformation of cultured cells induced by YAP (5SA). In addition, the increased nuclear localization of YAP (5SA) and its enhanced activation of TEAD-dependent transcription of the cell proliferation gene CTGF were strongly reduced when the PDZ-binding motif was deleted. Similarly, in mouse liver, deletion of the PDZ-binding motif suppressed nuclear localization of YAP (5SA) and YAP (5SA)-induced CTGF expression. Taken together, our results indicate that the PDZ-binding motif of YAP is critical for YAP-mediated oncogenesis, and that this effect is mediated by YAP’s co-activation of TEAD-mediated CTGF transcription

The PDZ-binding motif of Yes-associated protein is required for its co-activation of TEAD-mediated CTGF transcription and oncogenic cell transforming activity

Energy Technology Data Exchange (ETDEWEB)

Shimomura, Tadanori; Miyamura, Norio; Hata, Shoji; Miura, Ryota; Hirayama, Jun, E-mail: hirayama.dbio@mri.tmd.ac.jp; Nishina, Hiroshi, E-mail: nishina.dbio@mri.tmd.ac.jp

2014-01-17

Highlights: •Loss of the PDZ-binding motif inhibits constitutively active YAP (5SA)-induced oncogenic cell transformation. •The PDZ-binding motif of YAP promotes its nuclear localization in cultured cells and mouse liver. •Loss of the PDZ-binding motif inhibits YAP (5SA)-induced CTGF transcription in cultured cells and mouse liver. -- Abstract: YAP is a transcriptional co-activator that acts downstream of the Hippo signaling pathway and regulates multiple cellular processes, including proliferation. Hippo pathway-dependent phosphorylation of YAP negatively regulates its function. Conversely, attenuation of Hippo-mediated phosphorylation of YAP increases its ability to stimulate proliferation and eventually induces oncogenic transformation. The C-terminus of YAP contains a highly conserved PDZ-binding motif that regulates YAP’s functions in multiple ways. However, to date, the importance of the PDZ-binding motif to the oncogenic cell transforming activity of YAP has not been determined. In this study, we disrupted the PDZ-binding motif in the YAP (5SA) protein, in which the sites normally targeted by Hippo pathway-dependent phosphorylation are mutated. We found that loss of the PDZ-binding motif significantly inhibited the oncogenic transformation of cultured cells induced by YAP (5SA). In addition, the increased nuclear localization of YAP (5SA) and its enhanced activation of TEAD-dependent transcription of the cell proliferation gene CTGF were strongly reduced when the PDZ-binding motif was deleted. Similarly, in mouse liver, deletion of the PDZ-binding motif suppressed nuclear localization of YAP (5SA) and YAP (5SA)-induced CTGF expression. Taken together, our results indicate that the PDZ-binding motif of YAP is critical for YAP-mediated oncogenesis, and that this effect is mediated by YAP’s co-activation of TEAD-mediated CTGF transcription.

FOXO1 is a direct target of EWS-Fli1 oncogenic fusion protein in Ewing's sarcoma cells

International Nuclear Information System (INIS)

Yang, Liu; Hu, Hsien-Ming; Zielinska-Kwiatkowska, Anna; Chansky, Howard A.

2010-01-01

Research highlights: → Inducible and reversible siRNA knockdown of an oncogenic fusion protein such as EWS-Fli1 is feasible and more advantageous than other siRNA methods. → The tumor suppressor gene FOXO1 is a new EWS-Fli1 target. → While trans-activators are known for the FOXO1 gene, there has been no report on negative regulators of FOXO1 transcription. → This study provides first evidence that the EWS-Fli1 oncogenic fusion protein can function as a transcriptional repressor of the FOXO1 gene. -- Abstract: Ewing's family tumors are characterized by a specific t(11;22) chromosomal translocation that results in the formation of EWS-Fli1 oncogenic fusion protein. To investigate the effects of EWS-Fli1 on gene expression, we carried out DNA microarray analysis after specific knockdown of EWS-Fli1 through transfection of synthetic siRNAs. EWS-Fli1 knockdown increased expression of genes such as DKK1 and p57 that are known to be repressed by EWS-Fli1 fusion protein. Among other potential EWS-Fli1 targets identified by our microarray analysis, we have focused on the FOXO1 gene since it encodes a potential tumor suppressor and has not been previously reported in Ewing's cells. To better understand how EWS-Fli1 affects FOXO1 expression, we have established a doxycycline-inducible siRNA system to achieve stable and reversible knockdown of EWS-Fli1 in Ewing's sarcoma cells. Here we show that FOXO1 expression in Ewing's cells has an inverse relationship with EWS-Fli1 protein level, and FOXO1 promoter activity is increased after doxycycline-induced EWS-Fli1 knockdown. In addition, we have found that direct binding of EWS-Fli1 to FOXO1 promoter is attenuated after doxycycline-induced siRNA knockdown of the fusion protein. Together, these results suggest that suppression of FOXO1 function by EWS-Fli1 fusion protein may contribute to cellular transformation in Ewing's family tumors.

Conditional Selection of Genomic Alterations Dictates Cancer Evolution and Oncogenic Dependencies.

Science.gov (United States)

Mina, Marco; Raynaud, Franck; Tavernari, Daniele; Battistello, Elena; Sungalee, Stephanie; Saghafinia, Sadegh; Laessle, Titouan; Sanchez-Vega, Francisco; Schultz, Nikolaus; Oricchio, Elisa; Ciriello, Giovanni

2017-08-14

Cancer evolves through the emergence and selection of molecular alterations. Cancer genome profiling has revealed that specific events are more or less likely to be co-selected, suggesting that the selection of one event depends on the others. However, the nature of these evolutionary dependencies and their impact remain unclear. Here, we designed SELECT, an algorithmic approach to systematically identify evolutionary dependencies from alteration patterns. By analyzing 6,456 genomes from multiple tumor types, we constructed a map of oncogenic dependencies associated with cellular pathways, transcriptional readouts, and therapeutic response. Finally, modeling of cancer evolution shows that alteration dependencies emerge only under conditional selection. These results provide a framework for the design of strategies to predict cancer progression and therapeutic response. Copyright © 2017 Elsevier Inc. All rights reserved.

From General Aberrant Alternative Splicing in Cancers and Its Therapeutic Application to the Discovery of an Oncogenic DMTF1 Isoform

Directory of Open Access Journals (Sweden)

Na Tian

2017-03-01

Full Text Available Alternative pre-mRNA splicing is a crucial process that allows the generation of diversified RNA and protein products from a multi-exon gene. In tumor cells, this mechanism can facilitate cancer development and progression through both creating oncogenic isoforms and reducing the expression of normal or controllable protein species. We recently demonstrated that an alternative cyclin D-binding myb-like transcription factor 1 (DMTF1 pre-mRNA splicing isoform, DMTF1β, is increasingly expressed in breast cancer and promotes mammary tumorigenesis in a transgenic mouse model. Aberrant pre-mRNA splicing is a typical event occurring for many cancer-related functional proteins. In this review, we introduce general aberrant pre-mRNA splicing in cancers and discuss its therapeutic application using our recent discovery of the oncogenic DMTF1 isoform as an example. We also summarize new insights in designing novel targeting strategies of cancer therapies based on the understanding of deregulated pre-mRNA splicing mechanisms.

Attenuated Recombinant Influenza A Virus Expressing HPV16 E6 and E7 as a Novel Therapeutic Vaccine Approach.

Directory of Open Access Journals (Sweden)

Christoph Jindra

Full Text Available Persistent infection with high-risk human papillomavirus (HPV types, most often HPV16 and HPV18, causes all cervical and most anal cancers, and a subset of vulvar, vaginal, penile and oropharyngeal carcinomas. Two prophylactic virus-like particle (VLPs-based vaccines, are available that protect against vaccine type-associated persistent infection and associated disease, yet have no therapeutic effect on existing lesions or infections. We have generated recombinant live-attenuated influenza A viruses expressing the HPV16 oncogenes E6 and E7 as experimental immunotherapeutic vaccine candidates. The influenza A virus life cycle lacks DNA intermediates as important safety feature. Different serotypes were generated to ensure efficient prime and boost immunizations. The immune response to vaccination in C57BL/6 mice was characterized by peptide ELISA and IFN-γ ELISpot, demonstrating induction of cell-mediated immunity to HPV16 E6 and E7 oncoproteins. Prophylactic and therapeutic vaccine efficacy was analyzed in the murine HPV16-positive TC-1 tumor challenge model. Subcutaneous (s.c. prime and boost vaccinations of mice with recombinant influenza A serotypes H1N1 and H3N2, followed by challenge with TC-1 cells resulted in complete protection or significantly reduced tumor growth as compared to control animals. In a therapeutic setting, s.c. vaccination of mice with established TC-1 tumors decelerated tumor growth and significantly prolonged survival. Importantly, intralesional vaccine administration induced complete tumor regression in 25% of animals, and significantly reduced tumor growth in 50% of mice. These results suggest recombinant E6E7 influenza viruses as a promising new approach for the development of a therapeutic vaccine against HPV-induced disease.

Merkel Cell Polyomavirus Infection of Animal Dermal Fibroblasts.

Science.gov (United States)

Liu, Wei; Krump, Nathan A; MacDonald, Margo; You, Jianxin

2018-02-15

Merkel cell polyomavirus (MCPyV) is the first polyomavirus to be associated with human cancer. Mechanistic studies attempting to fully elucidate MCPyV's oncogenic mechanisms have been hampered by the lack of animal models for MCPyV infection. In this study, we examined the ability of MCPyV-GFP pseudovirus (containing a green fluorescent protein [GFP] reporter construct), MCPyV recombinant virions, and several MCPyV chimeric viruses to infect dermal fibroblasts isolated from various model animals, including mouse ( Mus musculus ), rabbit ( Oryctolagus cuniculus ), rat ( Rattus norvegicus ), chimpanzee ( Pan troglodytes ), rhesus macaque ( Macaca mulatta ), patas monkey ( Erythrocebus patas ), common woolly monkey ( Lagothrix lagotricha ), red-chested mustached tamarin ( Saguinus labiatus ), and tree shrew ( Tupaia belangeri ). We found that MCPyV-GFP pseudovirus was able to enter the dermal fibroblasts of all species tested. Chimpanzee dermal fibroblasts were the only type that supported vigorous MCPyV gene expression and viral replication, and they did so to a level beyond that of human dermal fibroblasts. We further demonstrated that both human and chimpanzee dermal fibroblasts produce infectious MCPyV virions that can successfully infect new cells. In addition, rat dermal fibroblasts supported robust MCPyV large T antigen expression after infection with an MCPyV chimeric virus in which the entire enhancer region of the MCPyV early promoter has been replaced with the simian virus 40 (SV40) analog. Our results suggest that viral transcription and/or replication events represent the major hurdle for MCPyV cross-species transmission. The capacity of rat dermal fibroblasts to support MCPyV early gene expression suggests that the rat is a candidate model organism for studying viral oncogene function during Merkel cell carcinoma (MCC) oncogenic progression. IMPORTANCE MCPyV plays an important role in the development of a highly aggressive form of skin cancer, Merkel

Long-range effects of direct-hit ultraviolet and particle radiation in oncogene activation

International Nuclear Information System (INIS)

Ladik, J.J.

1990-01-01

A simple statistical analysis shows that the oncogene-activation effect of chemical carcinogens cannot be explained if one takes into account only short-range effects. As one of the most probable solid state physical long-range effects, the generation at the site of carcinogen binding of travelling solitary waves, which can interfere with DNA-blocking protein interactions, is discussed. It has been shown that the direct hit carcinogenic effects on DNA by ultraviolet--or particle radiation can also be explained by the generation of solitary waves (in the latter case the first step is a collective plasma oscillation which decays to individual local excitations and ionizations)

An Epstein-Barr virus anti-apoptotic protein constitutively expressed in transformed cells and implicated in burkitt lymphomagenesis: the Wp/BHRF1 link.

Directory of Open Access Journals (Sweden)

Gemma L Kelly

2009-03-01

Full Text Available Two factors contribute to Burkitt lymphoma (BL pathogenesis, a chromosomal translocation leading to c-myc oncogene deregulation and infection with Epstein-Barr virus (EBV. Although the virus has B cell growth-transforming ability, this may not relate to its role in BL since many of the transforming proteins are not expressed in the tumor. Mounting evidence supports an alternative role, whereby EBV counteracts the high apoptotic sensitivity inherent to the c-myc-driven growth program. In that regard, a subset of BLs carry virus mutants in a novel form of latent infection that provides unusually strong resistance to apoptosis. Uniquely, these virus mutants use Wp (a viral promoter normally activated early in B cell transformation and express a broader-than-usual range of latent antigens. Here, using an inducible system to express the candidate antigens, we show that this marked apoptosis resistance is mediated not by one of the extended range of EBNAs seen in Wp-restricted latency but by Wp-driven expression of the viral bcl2 homologue, BHRF1, a protein usually associated with the virus lytic cycle. Interestingly, this Wp/BHRF1 connection is not confined to Wp-restricted BLs but appears integral to normal B cell transformation by EBV. We find that the BHRF1 gene expression recently reported in newly infected B cells is temporally linked to Wp activation and the presence of W/BHRF1-spliced transcripts. Furthermore, just as Wp activity is never completely eclipsed in in vitro-transformed lines, low-level BHRF1 transcripts remain detectable in these cells long-term. Most importantly, recognition by BHRF1-specific T cells confirms that such lines continue to express the protein independently of any lytic cycle entry. This work therefore provides the first evidence that BHRF1, the EBV bcl2 homologue, is constitutively expressed as a latent protein in growth-transformed cells in vitro and, in the context of Wp-restricted BL, may contribute to virus

Oncogenic S1P signalling in EBV-associated nasopharyngeal carcinoma activates AKT and promotes cell migration through S1P receptor 3.

Science.gov (United States)

Lee, Hui Min; Lo, Kwok-Wai; Wei, Wenbin; Tsao, Sai Wah; Chung, Grace Tin Yun; Ibrahim, Maha Hafez; Dawson, Christopher W; Murray, Paul G; Paterson, Ian C; Yap, Lee Fah

2017-05-01

Undifferentiated nasopharyngeal carcinoma (NPC) is a cancer with high metastatic potential that is consistently associated with Epstein-Barr virus (EBV) infection. In this study, we have investigated the functional contribution of sphingosine-1-phosphate (S1P) signalling to the pathogenesis of NPC. We show that EBV infection or ectopic expression of the EBV-encoded latent genes (EBNA1, LMP1, and LMP2A) can up-regulate sphingosine kinase 1 (SPHK1), the key enzyme that produces S1P, in NPC cell lines. Exogenous addition of S1P promotes the migration of NPC cells through the activation of AKT; shRNA knockdown of SPHK1 resulted in a reduction in the levels of activated AKT and inhibition of cell migration. We also show that S1P receptor 3 (S1PR3) mRNA is overexpressed in EBV-positive NPC patient-derived xenografts and a subset of primary NPC tissues, and that knockdown of S1PR3 suppressed the activation of AKT and the S1P-induced migration of NPC cells. Taken together, our data point to a central role for EBV in mediating the oncogenic effects of S1P in NPC and identify S1P signalling as a potential therapeutic target in this disease. Copyright © 2017 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd. Copyright © 2017 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.

Evolutionary relationship of alfalfa mosaic virus with cucumber mosaic virus and brome mosaic virus

OpenAIRE

Savithri, HS; Murthy, MRN

1983-01-01

The amino acid sequences of the non-structural protein (molecular weight 35,000; 3a protein) from three plant viruses - cucumber mosaic, brome mosaic and alfalfa mosaic have been systematically compared using the partial genomic sequences for these three viruses already available. The 3a protein of cucumber mosaic virus has an amino acid sequence homology of 33.7% with the corresponding protein of brome mosaic virus. A similar protein from alfalfa mosaic virus has a homology of 18.2% and 14.2...

Modulation of the tumor microenvironment by Epstein-Barr virus latent membrane protein 1 in nasopharyngeal carcinoma.

Science.gov (United States)

Yoshizaki, Tomokazu; Kondo, Satoru; Endo, Kazuhira; Nakanishi, Yosuke; Aga, Mitsuharu; Kobayashi, Eiji; Hirai, Nobuyuki; Sugimoto, Hisashi; Hatano, Miyako; Ueno, Takayoshi; Ishikawa, Kazuya; Wakisaka, Naohiro

2018-02-01

Latent membrane protein 1 (LMP1) is a primary oncogene encoded by the Epstein-Barr virus, and various portions of LMP1 are detected in nasopharyngeal carcinoma (NPC) tumor cells. LMP1 has been extensively studied since the discovery of its transforming property in 1985. LMP1 promotes cancer cell growth during NPC development and facilitates the interaction of cancer cells with surrounding stromal cells for invasion, angiogenesis, and immune modulation. LMP1 is detected in 100% of pre-invasive NPC tumors and in approximately 50% of advanced NPC tumors. Moreover, a small population of LMP1-expressing cells in advanced NPC tumor tissue is proposed to orchestrate NPC tumor tissue maintenance and development through cancer stem cells and progenitor cells. Recent studies suggest that LMP1 activity shifts according to tumor development stage, but it still has a pivotal role during all stages of NPC development. © 2017 The Authors. Cancer Science published by John Wiley & Sons Australia, Ltd on behalf of Japanese Cancer Association.

XMEN disease: a new primary immunodeficiency affecting Mg2+ regulation of immunity against Epstein-Barr virus.

Science.gov (United States)

Li, Feng-Yen; Chaigne-Delalande, Benjamin; Su, Helen; Uzel, Gulbu; Matthews, Helen; Lenardo, Michael J

2014-04-03

Epstein-Barr virus (EBV) is an oncogenic gammaherpesvirus that infects and persists in 95% of adults worldwide and has the potential to cause fatal disease, especially lymphoma, in immunocompromised hosts. Primary immunodeficiencies (PIDs) that predispose to EBV-associated malignancies have provided novel insights into the molecular mechanisms of immune defense against EBV. We have recently characterized a novel PID now named "X-linked immunodeficiency with magnesium defect, EBV infection, and neoplasia" (XMEN) disease characterized by loss-of-function mutations in the gene encoding magnesium transporter 1 (MAGT1), chronic high-level EBV with increased EBV-infected B cells, and heightened susceptibility to EBV-associated lymphomas. The genetic etiology of XMEN disease has revealed an unexpected quantitative role for intracellular free magnesium in immune functions and has led to novel diagnostic and therapeutic strategies. Here, we review the clinical presentation, genetic mutation spectrum, molecular mechanisms of pathogenesis, and diagnostic and therapeutic considerations for this previously unrecognized disease.

A New Strategy to Control and Eradicate "Undruggable" Oncogenic K-RAS-Driven Pancreatic Cancer: Molecular Insights and Core Principles Learned from Developmental and Evolutionary Biology.

Science.gov (United States)

Van Sciver, Robert E; Lee, Michael P; Lee, Caroline Dasom; Lafever, Alex C; Svyatova, Elizaveta; Kanda, Kevin; Colliver, Amber L; Siewertsz van Reesema, Lauren L; Tang-Tan, Angela M; Zheleva, Vasilena; Bwayi, Monicah N; Bian, Minglei; Schmidt, Rebecca L; Matrisian, Lynn M; Petersen, Gloria M; Tang, Amy H

2018-05-14

Oncogenic K-RAS mutations are found in virtually all pancreatic cancers, making K-RAS one of the most targeted oncoproteins for drug development in cancer therapies. Despite intense research efforts over the past three decades, oncogenic K-RAS has remained largely "undruggable". Rather than targeting an upstream component of the RAS signaling pathway (i.e., EGFR/HER2) and/or the midstream effector kinases (i.e., RAF/MEK/ERK/PI3K/mTOR), we propose an alternative strategy to control oncogenic K-RAS signal by targeting its most downstream signaling module, Seven-In-Absentia Homolog (SIAH). SIAH E3 ligase controls the signal output of oncogenic K-RAS hyperactivation that drives unchecked cell proliferation, uncontrolled tumor growth, and rapid cancer cell dissemination in human pancreatic cancer. Therefore, SIAH is an ideal therapeutic target as it is an extraordinarily conserved downstream signaling gatekeeper indispensable for proper RAS signaling. Guided by molecular insights and core principles obtained from developmental and evolutionary biology, we propose an anti-SIAH-centered anti-K-RAS strategy as a logical and alternative anticancer strategy to dampen uncontrolled K-RAS hyperactivation and halt tumor growth and metastasis in pancreatic cancer. The clinical utility of developing SIAH as both a tumor-specific and therapy-responsive biomarker, as well as a viable anti-K-RAS drug target, is logically simple and conceptually innovative. SIAH clearly constitutes a major tumor vulnerability and K-RAS signaling bottleneck in pancreatic ductal adenocarcinoma (PDAC). Given the high degree of evolutionary conservation in the K-RAS/SIAH signaling pathway, an anti-SIAH-based anti-PDAC therapy will synergize with covalent K-RAS inhibitors and direct K-RAS targeted initiatives to control and eradicate pancreatic cancer in the future.

Oncogenic c-Myc-induced lymphomagenesis is inhibited non-redundantly by the p19Arf–Mdm2–p53 and RP–Mdm2–p53 pathways

OpenAIRE

Meng, X; Carlson, NR; Dong, J; Zhang, Y

2015-01-01

The multifaceted oncogene c-Myc plays important roles in the development and progression of human cancer. Recent in vitro and in vivo studies have shown that the p19Arf–Mdm2–p53 and the ribosomal protein (RP)–Mdm2–p53 pathways are both essential in preventing oncogenic c-Myc-induced tumorigenesis. Disruption of each pathway individually by p19Arf deletion or by Mdm2C305F mutation, which disrupts RP-Mdm2 binding, accelerates Eμ-myc transgene-induced pre-B/B-cell lymphoma in mice at seemingly s...

A sparse regulatory network of copy-number driven gene expression reveals putative breast cancer oncogenes.

Science.gov (United States)

Yuan, Yinyin; Curtis, Christina; Caldas, Carlos; Markowetz, Florian

2012-01-01

Copy number aberrations are recognized to be important in cancer as they may localize to regions harboring oncogenes or tumor suppressors. Such genomic alterations mediate phenotypic changes through their impact on expression. Both cis- and transacting alterations are important since they may help to elucidate putative cancer genes. However, amidst numerous passenger genes, trans-effects are less well studied due to the computational difficulty in detecting weak and sparse signals in the data, and yet may influence multiple genes on a global scale. We propose an integrative approach to learn a sparse interaction network of DNA copy-number regions with their downstream transcriptional targets in breast cancer. With respect to goodness of fit on both simulated and real data, the performance of sparse network inference is no worse than other state-of-the-art models but with the advantage of simultaneous feature selection and efficiency. The DNA-RNA interaction network helps to distinguish copy-number driven expression alterations from those that are copy-number independent. Further, our approach yields a quantitative copy-number dependency score, which distinguishes cis- versus trans-effects. When applied to a breast cancer data set, numerous expression profiles were impacted by cis-acting copy-number alterations, including several known oncogenes such as GRB7, ERBB2, and LSM1. Several trans-acting alterations were also identified, impacting genes such as ADAM2 and BAGE, which warrant further investigation. An R package named lol is available from www.markowetzlab.org/software/lol.html.

Chromosome breakage at sites of oncogenes in a population accidentally exposed to radioactive chemical pollution

International Nuclear Information System (INIS)

Ilyinskikh, N.N.; IIlyinskikh, I.N.; Ilyinskikh, E.N.

2003-01-01

The purpose of the present study was to investigate the level of aberrations at fragile sites of chromosomes in peripheral blood lymphocytes of the population of an area polluted with radionuclides, following an accident at the Siberian Chemical Plant (SCP). We carried out the micro-nucleus test to screen people with radiation-related cytogenetic effects. Of the 1246 examined inhabitants of the settlement of Samus, 148 showed a significantly increased frequency of micro-nucleated erythrocytes and were selected for the chromosome analysis as a radiation-exposed group. Additional analysis was carried out on 40 patients with gastric cancer and atrophic gastritis with stage II-III epithelial dysplasia. Eighty six individuals from a non-polluted area were used as a control group. Chromosomal breaks and exchanges occurred preferentially in chromosomes 3 and 6 among radiation-exposed persons and patients. The regions 3p14-3p25 and 6p23 were damaged most often. There was a tendency towards preferential involvement at q21-q25 of chromosome 6 in patients with gastric cancer and atrophic gastritis. Specific damage at certain chromosome sites was observed in the radiation-exposed population as well as in patients with gastric cancer. Most often this damage were located near oncogene loci which could imply that chromosome damage induced by radiation is likely to be a predisposing factor to the expression of oncogenes and malignant transformation of cells in exposed individuals. (author)

EWS/FLI mediates transcriptional repression via NKX2.2 during oncogenic transformation in Ewing's sarcoma.

Directory of Open Access Journals (Sweden)

Leah A Owen

2008-04-01

Full Text Available EWS/FLI is a master regulator of Ewing's sarcoma formation. Gene expression studies in A673 Ewing's sarcoma cells have demonstrated that EWS/FLI downregulates more genes than it upregulates, suggesting that EWS/FLI, and/or its targets, function as transcriptional repressors. One critical EWS/FLI target, NKX2.2, is a transcription factor that contains both transcriptional activation and transcriptional repression domains, raising the possibility that it mediates portions of the EWS/FLI transcriptional signature. We now report that microarray analysis demonstrated that the transcriptional profile of NKX2.2 consists solely of downregulated genes, and overlaps with the EWS/FLI downregulated signature, suggesting that NKX2.2 mediates oncogenic transformation via transcriptional repression. Structure-function analysis revealed that the DNA binding and repressor domains in NKX2.2 are required for oncogenesis in Ewing's sarcoma cells, while the transcriptional activation domain is completely dispensable. Furthermore, blockade of TLE or HDAC function, two protein families thought to mediate the repressive function of NKX2.2, inhibited the transformed phenotype and reversed the NKX2.2 transcriptional profile in Ewing's sarcoma cells. Whole genome localization studies (ChIP-chip revealed that a significant portion of the NKX2.2-repressed gene expression signature was directly mediated by NKX2.2 binding. These data demonstrate that the transcriptional repressive function of NKX2.2 is necessary, and sufficient, for the oncogenic phenotype of Ewing's sarcoma, and suggest a therapeutic approach to this disease.

Oncogenic kinase NPM/ALK induces through STAT3 expression of immunosuppressive protein CD274 (PD-L1, B7-H1)

DEFF Research Database (Denmark)

Marzec, Michal; Zhang, Qian; Goradia, Ami

2008-01-01

The mechanisms of malignant cell transformation caused by the oncogenic, chimeric nucleophosmin (NPM)/anaplastic lymphoma kinase (ALK) remain only partially understood, with most of the previous studies focusing mainly on the impact of NPM/ALK on cell survival and proliferation. Here we report th...

Chemically Induced Degradation of the Oncogenic Transcription Factor BCL6

Directory of Open Access Journals (Sweden)

Nina Kerres

2017-09-01

Full Text Available The transcription factor BCL6 is a known driver of oncogenesis in lymphoid malignancies, including diffuse large B cell lymphoma (DLBCL. Disruption of its interaction with transcriptional repressors interferes with the oncogenic effects of BCL6. We used a structure-based drug design to develop highly potent compounds that block this interaction. A subset of these inhibitors also causes rapid ubiquitylation and degradation of BCL6 in cells. These compounds display significantly stronger induction of expression of BCL6-repressed genes and anti-proliferative effects than compounds that merely inhibit co-repressor interactions. This work establishes the BTB domain as a highly druggable structure, paving the way for the use of other members of this protein family as drug targets. The magnitude of effects elicited by this class of BCL6-degrading compounds exceeds that of our equipotent non-degrading inhibitors, suggesting opportunities for the development of BCL6-based lymphoma therapeutics.

Loss of Dependence on Continued Expression of the Human Papillomavirus 16 E7 Oncogene in Cervical Cancers and Precancerous Lesions Arising in Fanconi Anemia Pathway-Deficient Mice

Science.gov (United States)

Park, Soyeong; Park, Jung Wook; Pitot, Henry C.

2016-01-01

ABSTRACT   Fanconi anemia (FA) is a rare genetic disorder caused by defects in DNA damage repair. FA patients often develop squamous cell carcinoma (SCC) at sites where high-risk human papillomaviruses (HPVs) are known to cause cancer, including the cervix. However, SCCs found in human FA patients are often HPV negative, even though the majority of female FA patients with anogenital cancers had preexisting HPV-positive dysplasia. We hypothesize that HPVs contribute to the development of SCCs in FA patients but that the continued expression of HPV oncogenes is not required for the maintenance of the cancer state because FA deficiency leads to an accumulation of mutations in cellular genes that render the cancer no longer dependent upon viral oncogenes. We tested this hypothesis, making use of Bi-L E7 transgenic mice in which we temporally controlled expression of HPV16 E7, the dominant viral oncogene in HPV-associated cancers. As seen before, the persistence of cervical neoplastic disease was highly dependent upon the continued expression of HPV16 E7 in FA-sufficient mice. However, in mice with FA deficiency, cervical cancers persisted in a large fraction of the mice after HPV16 E7 expression was turned off, indicating that these cancers had escaped from their dependency on E7. Furthermore, the severity of precancerous lesions also failed to be reduced significantly in the mice with FA deficiency upon turning off expression of E7. These findings confirm our hypothesis and may explain the fact that, while FA patients have a high frequency of infections by HPVs and HPV-induced precancerous lesions, the cancers are frequently HPV negative. Importance   Fanconi anemia (FA) patients are at high risk for developing squamous cell carcinoma (SCC) at sites where high-risk human papillomaviruses (HPVs) frequently cause cancer. Yet these SCCs are often HPV negative. FA patients have a genetic defect in their capacity to repair damaged DNA. HPV oncogenes cause an

MicroRNA-26a-mediated regulation of interleukin-2 expression in transformed avian lymphocyte lines

Directory of Open Access Journals (Sweden)

Smith Lorraine P

2010-05-01

Full Text Available Abstract Background Micro(miRNAs are a class of small non-coding RNAs that play critical roles in the induction of various cancers, including lymphomas induced by oncogenic viruses. While some of the miRNAs are oncogenic, miRNAs such as miR-26a are consistently downregulated in a number of cancers, demonstrating their potential tumor suppressor functions. Global miRNA expression profiles of a number of virus-transformed avian lymphoma cell lines have shown downregulation of gga-miR-26a expression, irrespective of molecular mechanisms of transformation or the viral aetiology. The neoplastic transformation of lymphocytes by many viruses accompanies high levels of proliferative responses, mostly mediated through cytokines such as IL-2. Chicken IL-2 can modulate T-cell proliferation and cytotoxicity in vitro and in vivo and dysregulation of IL-2 expression is observed in diseases such as leukaemia. Results The expression levels of gga-miR-26a in chicken lymphoma cells transformed by 3 distinct avian oncogenic viruses, viz Marek's disease virus (MDV, avian leukosis virus (ALV and Reticuloendotheliosis virus (REV were consistently downregulated compared to the levels in the normal lymphocytes. This downregulation of miR-26a regardless of the viral etiology and molecular mechanisms of transformation was consistent with the tumor suppressor role of this miRNA. Notwithstanding this well-established role in cancer, we demonstrate the additional role of this miRNA in directly targeting chicken IL-2 through reporter and biochemical assays. The downregulation of miR-26a can relieve the suppressive effect of this miRNA on IL-2 expression. Conclusions We show that miR-26a is globally downregulated in a number of avian lymphoma cells irrespective of the mechanisms of transformation, reiterating the highly conserved tumor suppressor function of this miRNA. However, with the potential for directly targeting chicken IL-2, the downregulation of miR-26a in these

scid Thymocytes with TCRbeta gene rearrangements are targets for the oncogenic effect of SCL and LMO1 transgenes.

Science.gov (United States)

Chervinsky, D S; Lam, D H; Melman, M P; Gross, K W; Aplan, P D

2001-09-01

SCL and LMO1 were both discovered by virtue of their activation by chromosomaltranslocation in patients with T-cell acute lymphoblastic leukemia (T-ALL). Overexpression of SCL and LMO1 in the thymus of transgenic mice leads to T-ALL at a young age. scid (severe combined immunodeficient) mice are unable to efficiently recombine antigen receptor genes and consequently display a developmental block at the CD4-CD8- to CD4+CD8+ transition. To test the hypothesis that this developmental block would protect SCL/LMO1 transgenic mice from developing T-ALL, we crossed the SCL and LMO1 transgenes onto a scid background. The age of onset for T-ALL in the SCL/LMO1/scid mice was significantly delayed (P < 0.001) compared with SCL/LMO1/wild-type mice. Intriguingly, all of the SCL/LMO1/scid malignancies displayed clonal, in-frame TCRbeta gene rearrangements. Taken together, these findings suggest that the "leaky" scid thymocyte that undergoes a productive TCRbeta gene rearrangement is susceptible to the oncogenic action of SCL and LMO1 and additionally suggests that TCRbeta gene rearrangements may be required for the oncogenic action of SCL and LMO1.

Epstein–Barr virus nuclear antigen 3C interact with p73: Interplay between a viral oncoprotein and cellular tumor suppressor

Energy Technology Data Exchange (ETDEWEB)

Sahu, Sushil Kumar; Mohanty, Suchitra; Kumar, Amit [Division of Infectious Disease Biology, Institute of Life Sciences, Nalco Square, Chandrasekharpur, Bhubaneswar 751023 (India); Kundu, Chanakya N. [School of Biotechnology, KIIT University, Bhubaneswar (India); Verma, Subhash C. [Department of Microbiology and Immunology, University of Nevada, School of Medicine, Reno, NV 89557 (United States); Choudhuri, Tathagata, E-mail: tatha@ils.res.in [Division of Infectious Disease Biology, Institute of Life Sciences, Nalco Square, Chandrasekharpur, Bhubaneswar 751023 (India); Department of Biotechnology, Siksha Bhavana, Visva Bharati, Santiniketan, Bolpur (India)

2014-01-05

The p73 protein has structural and functional homology with the tumor suppressor p53, which plays an important role in cell cycle regulation, apoptosis, and DNA repair. The p73 locus encodes both a tumor suppressor (TAp73) and a putative oncogene (ΔNp73). p73 May play a significant role in p53-deficient lymphomas infected with Epstein–Barr virus (EBV). EBV produces an asymptomatic infection in the majority of the global population, but it is associated with several human B-cell malignancies. The EBV-encoded Epstein–Barr virus nuclear antigen 3C (EBNA3C) is thought to disrupt the cell cycle checkpoint by interacting directly with p53 family proteins. Doxorubicin, a commonly used chemotherapeutic agent, induces apoptosis through p53 and p73 signaling such that the lowΔNp73 level promotes the p73-mediated intrinsic pathway of apoptosis. In this report, we investigated the mechanism by which EBV infection counters p73α-induced apoptosis through EBNA3C. - Highlights: • EBV-encoded EBNA3C suppresses doxorubicin-induced apoptosis in B-cell lymphomas. • EBNA3C binds to p73 to suppress its apoptotic effect. • EBNA3C maintains latency by regulating downstream mitochondrial pathways.

Epstein–Barr virus nuclear antigen 3C interact with p73: Interplay between a viral oncoprotein and cellular tumor suppressor

International Nuclear Information System (INIS)

Sahu, Sushil Kumar; Mohanty, Suchitra; Kumar, Amit; Kundu, Chanakya N.; Verma, Subhash C.; Choudhuri, Tathagata

2014-01-01

The p73 protein has structural and functional homology with the tumor suppressor p53, which plays an important role in cell cycle regulation, apoptosis, and DNA repair. The p73 locus encodes both a tumor suppressor (TAp73) and a putative oncogene (ΔNp73). p73 May play a significant role in p53-deficient lymphomas infected with Epstein–Barr virus (EBV). EBV produces an asymptomatic infection in the majority of the global population, but it is associated with several human B-cell malignancies. The EBV-encoded Epstein–Barr virus nuclear antigen 3C (EBNA3C) is thought to disrupt the cell cycle checkpoint by interacting directly with p53 family proteins. Doxorubicin, a commonly used chemotherapeutic agent, induces apoptosis through p53 and p73 signaling such that the lowΔNp73 level promotes the p73-mediated intrinsic pathway of apoptosis. In this report, we investigated the mechanism by which EBV infection counters p73α-induced apoptosis through EBNA3C. - Highlights: • EBV-encoded EBNA3C suppresses doxorubicin-induced apoptosis in B-cell lymphomas. • EBNA3C binds to p73 to suppress its apoptotic effect. • EBNA3C maintains latency by regulating downstream mitochondrial pathways

Oncogenic driver genes and the inflammatory microenvironment dictate liver tumor phenotype

DEFF Research Database (Denmark)

Matter, Matthias S; Marquardt, Jens U; Andersen, Jesper B

2016-01-01

The majority of hepatocellular carcinoma (HCC) develops in the background of chronic liver inflammation caused by viral hepatitis and alcoholic or non-alcoholic steatohepatitis. However, the impact of different types of chronic inflammatory microenvironments on the phenotypes of tumors generated...... with transcriptome profiles from human HCCs further demonstrated that AKT-CAT tumors generated in the context of chronic liver inflammation showed enrichment of poor prognosis gene sets or decrease of good prognosis gene sets. In contrast, DDC had a more subtle effect on AKT-NRAS(G12V) tumors and primarily enhanced...... by distinct oncogenes is largely unresolved. To address this issue, we generated murine liver tumors by constitutively active AKT-1 (AKT) and β-catenin (CAT) followed by induction of chronic liver inflammation by 3,5-diethoxycarbonyl-1,4-dihydrocollidine (DDC) and carbon tetrachloride (CCl4 ). Also...

Vaccines against papillomavirus infections and disease Vacunas contra el virus del papiloma humano y cáncer cervical invasor

Directory of Open Access Journals (Sweden)

Luisa Lina Villa

2003-01-01

Full Text Available Squamous cell carcinoma of the uterine cervix is the second cause of cancer-related deaths in women, the higher incidence being observed in developing countries. Infection with oncogenic types of human papillomavirus (HPV is considered the major risk factor for the development of malignancies in the uterine cervix. However, HPV is considered to be a necessary but not sufficient cause for cervical cancer and, therefore, other factors contribute to the carcinogenic process, both present in the environment and from the host. Studies performed in animals, and more recently in humans, indicate that vaccination against the capsid proteins of the virus can prevent efficiently from infection. Furthermore, therapeutic vaccines are under investigation aiming the regression of papillomavirus induced tumors. The scientific basis for the development of papillomavirus vaccines and present status of clinical trials will be addressed in this chapter.El cáncer de células escamosas del cérvix uterino es la segunda causa de muerte relacionada con cáncer en mujeres en el mundo; la incidencia más alta se ha observado en países en desarrollo. La infección con tipos oncogénicos de virus de papiloma humano es considerado el factor de riesgo principal para el desarrollo de malignidad en el cérvix uterino. Sin embargo, el virus es considerado una causa necesaria pero no suficiente para desarrollo de cáncer cervical y, por lo tanto, existen otros factores en el ambiente y en el huésped que contribuyen al proceso carcinogénico. Estudios desarrollados en animales, y más recientemente en humanos, indican que la vacunación en contra de la cápside de las proteínas del virus puede prevenir eficientemente la infección en forma profiláctica; además, las vacunas terapéuticas están bajo investigación con el propósito de promover regresión de los tumores inducidos por virus de papiloma humano. Las bases científicas de las vacunas desarrolladas contra este

Presence of adenovirus species C in infiltrating lymphocytes of human sarcoma.

Directory of Open Access Journals (Sweden)

Karin Kosulin

Full Text Available Human adenoviruses are known to persist in T-lymphocytes of tonsils, adenoids and intestinal tract. The oncogenic potential of different adenovirus types has been widely studied in rodents, in which adenovirus inoculation can induce multiple tumors such as undifferentiated sarcomas, adenocarcinomas and neuroectodermal tumors. However, the oncogenic potential of this virus has never been proven in human subjects. Using a highly sensitive broad-spectrum qRT-PCR, we have screened a set of different human sarcomas including leiomyosarcoma, liposarcoma and gastro intestinal stroma tumors. Primers binding the viral oncogene E1A and the capsid-coding gene Hexon were used to detect the presence of adenovirus DNA in tumor samples. We found that 18% of the tested leiomyosarcomas and 35% of the liposarcomas were positive for the presence of adenovirus DNA, being species C types the most frequently detected adenoviruses. However, only in one sample of the gastro intestinal stroma tumors the virus DNA could be detected. The occurrence of adenovirus in the tumor sections was confirmed by subsequent fluorescence in-situ-hybridization analysis and co-staining with the transcription factor Bcl11b gives evidence for the presence of the virus in infiltrating T-lymphocytes within the tumors. Together these data underline, for the first time, the persistence of adenovirus in T-lymphocytes infiltrated in muscular and fatty tissue tumor samples. If an impaired immune system leads to the viral persistence and reactivation of the virus is involved in additional diseases needs further investigation.

Plasma levels of calcitonin in medullary thyroid carcinoma patients with and without the RET proto-oncogene mutations in exons 10 and 11

Directory of Open Access Journals (Sweden)

Samira Ehyayi

2017-09-01

Conclusion: Routine measurement of calcitonin has been investigated as a screening method for the diagnosis of medullary thyroid carcinoma patients. Nevertheless, additional data are required to definitely support routine measurement of calcitonin due to the role of RET proto-oncogene.

Comparative analysis of chrysanthemum transcriptome in response to three RNA viruses: Cucumber mosaic virus, Tomato spotted wilt virus and Potato virus X.

Science.gov (United States)

Choi, Hoseong; Jo, Yeonhwa; Lian, Sen; Jo, Kyoung-Min; Chu, Hyosub; Yoon, Ju-Yeon; Choi, Seung-Kook; Kim, Kook-Hyung; Cho, Won Kyong

2015-06-01

The chrysanthemum is one of popular flowers in the world and a host for several viruses. So far, molecular interaction studies between the chrysanthemum and viruses are limited. In this study, we carried out a transcriptome analysis of chrysanthemum in response to three different viruses including Cucumber mosaic virus (CMV), Tomato spotted wilt virus (TSWV) and Potato virus X (PVX). A chrysanthemum 135K microarray derived from expressed sequence tags was successfully applied for the expression profiles of the chrysanthemum at early stage of virus infection. Finally, we identified a total of 125, 70 and 124 differentially expressed genes (DEGs) for CMV, TSWV and PVX, respectively. Many DEGs were virus specific; however, 33 DEGs were commonly regulated by three viruses. Gene ontology (GO) enrichment analysis identified a total of 132 GO terms, and of them, six GO terms related stress response and MCM complex were commonly identified for three viruses. Several genes functioning in stress response such as chitin response and ethylene mediated signaling pathway were up-regulated indicating their involvement in establishment of host immune system. In particular, TSWV infection significantly down-regulated genes related to DNA metabolic process including DNA replication, chromatin organization, histone modification and cytokinesis, and they are mostly targeted to nucleosome and MCM complex. Taken together, our comparative transcriptome analysis revealed several genes related to hormone mediated viral stress response and DNA modification. The identified chrysanthemums genes could be good candidates for further functional study associated with resistant to various plant viruses.

Long-range gap junctional signaling controls oncogene-mediated tumorigenesis in Xenopus laevis embryos

Directory of Open Access Journals (Sweden)

Brook T Chernet

2015-01-01

Full Text Available In addition to the immediate microenvironment, long-range signaling may be an important component of cancer. Molecular-genetic analyses have implicated gap junctions – key mediators of cell-cell communication – in carcinogenesis. We recently showed that the resting voltage potential of distant cell groups is a key determinant of metastatic transformation and tumor induction. Here, we show in the Xenopus laevis model that gap junctional communication (GJC is a modulator of the long-range bioelectric signaling that regulates tumor formation. Genetic disruption of GJC taking place within tumors, within remote host tissues, or between the host and tumors – significantly lowers the incidence of tumors induced by KRAS mutations. The most pronounced suppression of tumor incidence was observed upon GJC disruption taking place farther away from oncogene-expressing cells, revealing a role for GJC in distant cells in the control of tumor growth. In contrast, enhanced GJC communication through the overexpression of wild-type connexin Cx26 increased tumor incidence. Our data confirm a role for GJC in tumorigenesis, and reveal that this effect is non-local. Based on these results and on published data on movement of ions through GJs, we present a quantitative model linking the GJC coupling and bioelectrical state of cells to the ability of oncogenes to initiate tumorigenesis. When integrated with data on endogenous bioelectric signaling during left-right patterning, the model predicts differential tumor incidence outcomes depending on the spatial configurations of gap junction paths relative to tumor location and major anatomical body axes. Testing these predictions, we found that the strongest influence of GJ modulation on tumor suppression by hyperpolarization occurred along the embryonic left-right axis. Together, these data reveal new, long-range aspects of cancer control by the host’s physiological parameters.

Trans-activation function of a 3' truncated X gene-cell fusion product from integrated hepatitis B virus DNA in chronic hepatitis tissues

International Nuclear Information System (INIS)

Takada, Shinako; Koike, Katsuro

1990-01-01

To investigate the expression and transactivation function of the X gene in integrated hepatitis B virus (HBV) DNA from chronic hepatitis tissues, a series of transfectants containing cloned integrated HBV DNAs was made and analyzed for X mRNA expression and trans-activation activity by using a chloramphenicol acetyltransferase assay. Most of the integrated HBV DNAs expressed X mRNA and encoded a product with trans-activation activity in spite of the loss of the 3' end region of the X gene due to integration. From cDNA cloning and sequence analysis of X mRNA transcribed from native or integrated HBV DNA, the X protein was found to be translated from the X open reading frame without splicing. For integrated HBV DNA, transcription was extended to a cellular flanking DNA and an X gene-cell fusion transcript was terminated by using a cellular poly(A) signal. The amino acid sequence deduced from an X-cell fusion transcript indicated truncation of the carboxyl-terminal five amino acids, but the upstream region of seven amino acids conserved among hepadnaviruses was retained in the integrated HBV DNA, suggesting that this conserved region is essential for the transactivation function of the X protein. These findings support the following explanation for hepatocarcinogenesis by HBV DNA integration: the expression of a cellular oncogene(s) is transactivated at the time of chronic infection by the increasing amounts of the integrated HBV gene product(s), such as the X-cell fusion product

Hepatitis B virus X promotes hepatocellular carcinoma development via nuclear protein 1 pathway

Energy Technology Data Exchange (ETDEWEB)

Bak, Yesol; Shin, Hye-jun; Bak, In seon [Disease Model Research Laboratory, Aging Intervention Research Center, Korea Research Institute of Bioscience and Biotechnology (KRIBB), Daejeon (Korea, Republic of); Yoon, Do-young [Department of Bioscience and Biotechnology, Bio/Molecular Informatics Center, Konkuk University, Seoul (Korea, Republic of); Yu, Dae-Yeul, E-mail: dyyu10@kribb.re.kr [Disease Model Research Laboratory, Aging Intervention Research Center, Korea Research Institute of Bioscience and Biotechnology (KRIBB), Daejeon (Korea, Republic of)

2015-10-30

Hepatocellular carcinoma (HCC) is one of the most common malignancies and chronic hepatitis B virus (HBV) infection is a major risk factor for HCC. Hepatitis B virus X (HBx) protein relates to trigger oncogenesis. HBx has oncogenic properties with a hyperproliferative response to HCC. Nuclear protein 1 (NUPR1) is a stress-response protein, frequently upregulated in several cancers. Recent data revealed that NUPR1 is involved in tumor progression, but its function in HCC is not revealed yet. Here we report HBx can induce NUPR1 in patients, mice, and HCC cell lines. In an HBx transgenic mouse model, we found that HBx overexpression upregulates NUPR1 expression consistently with tumor progression. Further, in cultured HBV positive cells, HBx knockdown induces downregulation of NUPR1. Smad4 is a representative transcription factor, regulated by HBx, and we showed that HBx upregulates NUPR1 by Smad4 dependent way. We found that NUPR1 can inhibit cell death and induce vasculogenic mimicry in HCC cell lines. Moreover, NUPR1 silencing in HepG2-HBx showed reduced cell motility. These results suggest that HBx can modulate NUPR1 expression through the Smad4 pathway and NUPR1 has a role in hepatocellular carcinoma progression. - Highlights: • NUPR1 is overexpressed in HBx transgenic mouse and HCC patients. • NUPR1 inactivation hampers the HBx induced growth, VM formation, and migration of HepG2 cells in vitro. • NUPR1 has a role for survival of HCC and mechanistically NUPR1 is activated by HBx-Smad4 axis.

Long Intergenic Noncoding RNA 00511 Acts as an Oncogene in Non–small-cell Lung Cancer by Binding to EZH2 and Suppressing p57

Directory of Open Access Journals (Sweden)

Cheng-Cao Sun

2016-01-01

Full Text Available Long noncoding RNAs (lncRNAs play crucial roles in carcinogenesis. However, the function and mechanism of lncRNAs in human non–small-cell lung cancer (NSCLC are still remaining largely unknown. Long intergenic noncoding RNA 00511 (LINC00511 has been found to be upregulated and acts as an oncogene in breast cancer, but little is known about its expression pattern, biological function and underlying mechanism in NSCLC. Herein, we identified LINC00511 as an oncogenic lncRNA by driving tumorigenesis in NSCLC. We found LINC00511 was upregulated and associated with oncogenesis, tumor size, metastasis, and poor prognosis in NSCLC. Moreover, LINC00511 affected cell proliferation, invasiveness, metastasis, and apoptosis in multiple NSCLC cell lines. Mechanistically, LINC00511 bound histone methyltransferase enhancer of zeste homolog 2 ((EZH2, the catalytic subunit of the polycomb repressive complex 2 (PRC2, a highly conserved protein complex that regulates gene expression by methylating lysine 27 on histone H3, and acted as a modular scaffold of EZH2/PRC2 complexes, coordinated their localization, and specified the histone modification pattern on the target genes, including p57, and consequently altered NSCLC cell biology. Thus, LINC00511 is mechanistically, functionally, and clinically oncogenic in NSCLC. Targeting LINC00511 and its pathway may be meaningful for treating patients with NSCLC.

Orphan nuclear receptor TLX functions as a potent suppressor of oncogene-induced senescence in prostate cancer via its transcriptional co-regulation of the CDKN1A (p21(WAF1) (/) (CIP1) ) and SIRT1 genes.

Science.gov (United States)

Wu, Dinglan; Yu, Shan; Jia, Lin; Zou, Chang; Xu, Zhenyu; Xiao, Lijia; Wong, Kam-Bo; Ng, Chi-Fai; Chan, Franky L

2015-05-01

Oncogene-induced senescence is an important tumour-suppressing mechanism to prevent both premalignant transformation and cancer progression. Overcoming this process is a critical step in early cancer development. The druggable orphan nuclear receptor TLX (NR2E1) is characterized as an important regulator of neural stem cells and is also implicated in the development of some brain tumours. However, its exact functional roles in cancer growth regulation still remain unclear. Here we report that TLX can act as a promoter of tumourigenesis in prostate cancer by suppressing oncogene-induced senescence. We determined that TLX exhibited an increased expression in high-grade prostate cancer tissues and many prostate cancer cell lines. Functional studies revealed that TLX could perform an oncogenic function in prostate cancer cells, as its knockdown triggered cellular senescence and cell growth arrest in vitro and in vivo, whereas its over-expression promoted the malignant growth of prostate cancer cells. Furthermore, enhancement of TLX activity, by either ectopic expression or ligand stimulation, could potently prevent doxorubicin-induced senescence in prostate cancer cells and also allow prostatic epithelial cells to escape oncogene-induced senescence induced either by activated oncogene H-Ras(G12V) or knockdown of tumour suppressor PTEN, via a mechanism of direct but differential transcriptional regulation of two senescence-associated genes, repression of CDKN1A and transactivation of SIRT1. Together, our present study shows, for the first time, that TLX may play an important role in prostate carcinogenesis through its suppression of oncogene-induced senescence, and also suggests that targeting the senescence-regulatory TLX is of potential therapeutic significance in prostate cancer. Copyright © 2015 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.

Pleomorphic Malignant Mesothelioma in a Broiler Breeder Infected with Avian Leucosis Virus Subgroup J.

Science.gov (United States)

Murakami, T; Sassa, Y

2018-04-01

Avian leucosis virus (ALV) is an oncogenic retrovirus that induces tumours including lymphoid leucosis and myeloid leucosis. Pleomorphic malignant mesothelioma and myelocytoma, which were thought to be induced by ALV subgroup J (ALV-J) infection, were identified in a 432-day-old broiler breeder. The bird showed no clinical signs; however, at necropsy examination there were multiple nodules in the alimentary tract. Microscopical analysis showed that these consisted of pleomorphic cells and myelocyte-like cells. Immunohistochemistry revealed that the pleomorphic cells were atypical and expressed cytokeratin, vimentin, c-kit, calretinin and ALV. The myelocyte-like cells were also positive for ALV. Retroviral type C particles were observed by electron microscopy. ALV-E and ALV-J nucleotide sequences were detected in DNA extracted from formalin-fixed and paraffin wax-embedded small intestinal tissue. Based on these results, the tumours were diagnosed as pleomorphic malignant mesothelioma and myelocytoma and were thought to have been induced by ALV-J infection. This is the first report of malignant mesothelioma associated with naturally acquired ALV-J infection. Copyright © 2018 Elsevier Ltd. All rights reserved.