WorldWideScience

Sample records for tumor gene int6

  1. Int6/eIF3e Is Essential for Proliferation and Survival of Human Glioblastoma Cells

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    Julie Sesen

    2014-01-01

    Full Text Available Glioblastomas (GBM are very aggressive and malignant brain tumors, with frequent relapses despite an appropriate treatment combining surgery, chemotherapy and radiotherapy. In GBM, hypoxia is a characteristic feature and activation of Hypoxia Inducible Factors (HIF-1α and HIF-2α has been associated with resistance to anti-cancer therapeutics. Int6, also named eIF3e, is the “e” subunit of the translation initiation factor eIF3, and was identified as novel regulator of HIF-2α. Eukaryotic initiation factors (eIFs are key factors regulating total protein synthesis, which controls cell growth, size and proliferation. The functional significance of Int6 and the effect of Int6/EIF3E gene silencing on human brain GBM has not yet been described and its role on the HIFs is unknown in glioma cells. In the present study, we show that Int6/eIF3e suppression affects cell proliferation, cell cycle and apoptosis of various GBM cells. We highlight that Int6 inhibition induces a diminution of proliferation through cell cycle arrest and increased apoptosis. Surprisingly, these phenotypes are independent of global cell translation inhibition and are accompanied by decreased HIF expression when Int6 is silenced. In conclusion, we demonstrate here that Int6/eIF3e is essential for proliferation and survival of GBM cells, presumably through modulation of the HIFs.

  2. The Drosophila orthologue of the INT6 onco-protein regulates mitotic microtubule growth and kinetochore structure.

    Directory of Open Access Journals (Sweden)

    Fioranna Renda

    2017-05-01

    Full Text Available INT6/eIF3e is a highly conserved component of the translation initiation complex that interacts with both the 26S proteasome and the COP9 signalosome, two complexes implicated in ubiquitin-mediated protein degradation. The INT6 gene was originally identified as the insertion site of the mouse mammary tumor virus (MMTV, and later shown to be involved in human tumorigenesis. Here we show that depletion of the Drosophila orthologue of INT6 (Int6 results in short mitotic spindles and deformed centromeres and kinetochores with low intra-kinetochore distance. Poleward flux of microtubule subunits during metaphase is reduced, although fluorescence recovery after photobleaching (FRAP demonstrates that microtubules remain dynamic both near the kinetochores and at spindle poles. Mitotic progression is delayed during metaphase due to the activity of the spindle assembly checkpoint (SAC. Interestingly, a deubiquitinated form of the kinesin Klp67A (a putative orthologue of human Kif18A accumulates near the kinetochores in Int6-depleted cells. Consistent with this finding, Klp67A overexpression mimics the Int6 RNAi phenotype. Furthermore, simultaneous depletion of Int6 and Klp67A results in a phenotype identical to RNAi of just Klp67A, which indicates that Klp67A deficiency is epistatic over Int6 deficiency. We propose that Int6-mediated ubiquitination is required to control the activity of Klp67A. In the absence of this control, excess of Klp67A at the kinetochore suppresses microtubule plus-end polymerization, which in turn results in reduced microtubule flux, spindle shortening, and centromere/kinetochore deformation.

  3. Tumor targeted gene therapy

    International Nuclear Information System (INIS)

    Kang, Joo Hyun

    2006-01-01

    Knowledge of molecular mechanisms governing malignant transformation brings new opportunities for therapeutic intervention against cancer using novel approaches. One of them is gene therapy based on the transfer of genetic material to an organism with the aim of correcting a disease. The application of gene therapy to the cancer treatment had led to the development of new experimental approaches such as suicidal gene therapy, inhibition of oncogenes and restoration of tumor-suppressor genes. Suicidal gene therapy is based on the expression in tumor cells of a gene encoding an enzyme that converts a prodrug into a toxic product. Representative suicidal genes are Herpes simplex virus type 1 thymidine kinase (HSV1-tk) and cytosine deaminase (CD). Especially, physicians and scientists of nuclear medicine field take an interest in suicidal gene therapy because they can monitor the location and magnitude, and duration of expression of HSV1-tk and CD by PET scanner

  4. Gene therapy and radiotherapy in malignant tumor

    International Nuclear Information System (INIS)

    Zhang Yaowen; Cao Yongzhen; Li Jin; Wang Qin

    2008-01-01

    Tumor treatment is one of the most important fields in medical research. Nowadays, a novel method which is combined gene therapy with radiotherapy plays an important role in the field of cancer research, and mainly includes immune gene therapy combined with radiotherapy, suicide gene therapy or tumor suppressor gene therapy combined with radiotherapy, antiangiogenesis gene therapy combined with radiotherapy and protective gene therapy combined with radiotherapy based on the technical features. This review summarized the current status of combined therapies of gene therapy and radiotherapy and possible mechanism. (authors)

  5. Gene expression profiling of laterally spreading tumors.

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    Minemura, Shoko; Tanaka, Takeshi; Arai, Makoto; Okimoto, Kenichiro; Oyamada, Arata; Saito, Keiko; Maruoka, Daisuke; Matsumura, Tomoaki; Nakagawa, Tomoo; Katsuno, Tatsuro; Kishimoto, Takashi; Yokosuka, Osamu

    2015-06-06

    Laterally spreading tumors (LSTs) are generally defined as lesions >10 mm in diameter, are characterized by lateral expansion along the luminal wall with a low vertical axis. In contrast to other forms of tumor, LSTs are generally considered to have a superficial growth pattern and the potential for malignancy. We focused on this morphological character of LSTs, and analyzed the gene expression profile of LSTs. The expression of 168 genes in 41 colorectal tumor samples (17 LST-adenoma, 12 LST-carcinoma, 12 Ip [pedunculated type of the Paris classification)-adenoma, all of which were 10 mm or more in diameter] was analyzed by PCR array. Based on the results, we investigated the expression levels of genes up-regulated in LST-adenoma, compared to Ip-adenoma, by hierarchical and K-means clustering. To confirm the results of the array analysis, using an additional 60 samples (38 LST-adenoma, 22 Ip-adenoma), we determined the localization of the gene product by immunohistochemical staining. The expression of 129 genes differed in colorectal tumors from normal mucosa by PCR array analysis. As a result of K-means clustering, the expression levels of five genes, AKT1, BCL2L1, ERBB2, MTA2 and TNFRSF25, were found to be significantly up-regulated (p < 0.05) in LST-adenoma, compared to Ip-adenoma. Immunohistochemical analysis showed that the BCL2L1 protein was significantly and meaningfully up-regulated in LST-adenoma compared to Ip-adenoma (p = 0.010). With respect to apoptosis status in LST-Adenoma, it assumes that BCL2L1 is anti-apoptotic protein, the samples such as BCL2L1 positive and TUNEL negative, or BCL2L1 negative and TUNEL positive are consistent with the assumption. 63.2 % LST-adenoma samples were consistent with the assumption. LSTs have an unusual profile of gene expression compared to other tumors and BCL2L1 might be concerned in the organization of LSTs.

  6. Identification of epigenetically silenced genes in tumor endothelial cells

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    Hellebrekers, Debby M. E. I.; Melotte, Veerle; Vire, Emmanuelle; Langenkamp, Elise; Molema, Grietje; Fuks, Francois; Herman, James G.; Van Criekinge, Wim; Griffioen, Arjan W.; van Engeland, Manon

    2007-01-01

    Tumor angiogenesis requires intricate regulation of gene expression in endothelial cells. We recently showed that DNA methyltransferase (DNMT) and histone deacetylase (HDAC) inhibitors directly repress endothelial cell growth and tumor angiogenesis, suggesting that epigenetic modifications mediated

  7. PTEN, a Tumor Suppressor Gene for Prostate Cancer

    National Research Council Canada - National Science Library

    Ittmann, Michael

    1999-01-01

    .... The PTEN gene is a tumor suppressor gene recently cloned from human chromosome 10q23.3 that encodes a lipid phosphatase which influences a variety of cellular processes that impact on the neoplastic phenotype...

  8. Immunotherapy of Malignancy by in vivo Gene Transfer into Tumors

    Science.gov (United States)

    Plautz, Gregory E.; Yang, Zhi-Yong; Wu, Bei-Yue; Gao, Xiang; Huang, Leaf; Nabel, Gary J.

    1993-05-01

    The immune system confers protection against a variety of pathogens and contributes to the surveillance and destruction of neoplastic cells. Several cell types participate in the recognition and lysis of tumors, and appropriate immune stimulation provides therapeutic effects in malignancy. Foreign major histocompatibility complex (MHC) proteins also serve as a potent stimulus to the immune system. In this report, a foreign MHC gene was introduced directly into malignant tumors in vivo in an effort to stimulate tumor rejection. In contrast to previous attempts to induce tumor immunity by cell-mediated gene transfer, the recombinant gene was introduced directly into tumors in vivo. Expression of the murine class I H-2K^s gene within the CT26 mouse colon adenocarcinoma (H-2K^d) or the MCA 106 fibrosarcoma (H-2K^b) induced a cytotoxic T-cell response to H-2K^s and, more importantly, to other antigens present on unmodified tumor cells. This immune response attenuated tumor growth and caused complete tumor regression in many cases. Direct gene transfer in vivo can therefore induce cell-mediated immunity against specific gene products, which provides an immunotherapeutic effect for malignancy, and potentially can be applied to the treatment of cancer and infectious diseases in man.

  9. Hypomethylation of tumor suppressor genes in odontogenic myxoma

    OpenAIRE

    Moreira,Paula Rocha; Cardoso,Fabiano Pereira; Brito,João Artur Ricieri; Batista,Aline Carvalho; Gomes,Carolina Cavaliéri; Gomez,Ricardo Santiago

    2011-01-01

    Odontogenic myxoma (OM) is an ectomesenchymal benign odontogenic tumor characterized by spindle or stellate-shaped cells embedded in an abundant myxoid or mucoid extracellular matrix. DNA methylation is characterized by the addition of methyl groups in cytosines within CpG islands in the promoter gene. DNA methylation can decrease the expression of tumor suppressor genes and contribute to the development of neoplastic lesions. The aim of study was to evaluate the methylation pattern of the tu...

  10. 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

  11. Expression of the p16{sup INK4a} tumor suppressor gene in rodent lung tumors

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    Swafford, D.S.; Tesfaigzi, J.; Belinsky, S.A.

    1995-12-01

    Aberrations on the short arm of chromosome 9 are among the earliest genetic changes in human cancer. p16{sup INK4a} is a candidate tumor suppressor gene that lies within human 9p21, a chromosome region associated with frequent loss of heterozygosity in human lung tumors. The p16{sup INK4a} protein functions as an inhibitor of cyclin D{sub 1}-dependent kinases that phosphorylate the retinoblastoma (Rb) tumor suppressor gene product enabling cell-cycle progression. Thus, overexpression of cyclin D{sub 1}, mutation of cyclin-dependent kinase genes, or loss of p16{sup INK4a} function, can all result in functional inactivation of Rb. Inactivation of Rb by mutation or deletion can result in an increase in p16{sup INK4a} transcription, suggesting that an increased p16{sup INK4a} expression in a tumor cell signals dysfunction of the pathway. The p16{sup (INK4a)} gene, unlike some tumor suppressor genes, is rarely inactivated by mutation. Instead, the expression of this gene is suppressed in some human cancers by hypermethylation of the CpG island within the first exon or by homozygous deletion: 686. Chromosome losses have been observed at 9p21 syntenic loci in tumors of the mouse and rat, two species often used as animal models for pulmonary carcinogenesis. Expression of p16{sup INK4a} is lost in some mouse tumor cell lines, often due to homozygous deletion. These observations indicate that p16{sup INK4a} dysfunction may play a role in the development of neoplasia in rodents as well as humans. The purpose of the current investigation was to define the extent to which p16{sup INK4a} dysfunction contributes to the development of rodent lung tumors and to determine the mechanism of inactivation of the gene. There is no evidence to suggest a loss of function of the p16{sup INK4a} tumor suppressor gene in these primary murine lung tumors by mutation, deletion, or methylation.

  12. Modeling and Targeting MYC Genes in Childhood Brain Tumors

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    Hutter, Sonja; Bolin, Sara; Weishaupt, Holger; Swartling, Fredrik J.

    2017-01-01

    Brain tumors are the second most common group of childhood cancers, accounting for about 20%–25% of all pediatric tumors. Deregulated expression of the MYC family of transcription factors, particularly c-MYC and MYCN genes, has been found in many of these neoplasms, and their expression levels are often correlated with poor prognosis. Elevated c-MYC/MYCN initiates and drives tumorigenesis in many in vivo model systems of pediatric brain tumors. Therefore, inhibition of their oncogenic function is an attractive therapeutic target. In this review, we explore the roles of MYC oncoproteins and their molecular targets during the formation, maintenance, and recurrence of childhood brain tumors. We also briefly summarize recent progress in the development of therapeutic approaches for pharmacological inhibition of MYC activity in these tumors. PMID:28333115

  13. RET is a potential tumor suppressor gene in colorectal cancer

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    Luo, Yanxin; Tsuchiya, Karen D.; Park, Dong Il; Fausel, Rebecca; Kanngurn, Samornmas; Welcsh, Piri; Dzieciatkowski, Slavomir; Wang, Jianping; Grady, William M.

    2012-01-01

    Cancer arises as the consequence of mutations and epigenetic alterations that activate oncogenes and inactivate tumor suppressor genes. Through a genome-wide screen for methylated genes in colon neoplasms, we identified aberrantly methylated RET in colorectal cancer. RET, a transmembrane receptor tyrosine kinase and a receptor for the GDNF-family ligands, was one of the first oncogenes to be identified and has been shown to be an oncogene in thyroid cancer and pheochromocytoma. However, unexpectedly, we found RET is methylated in 27% of colon adenomas and in 63% of colorectal cancers, and now provide evidence that RET has tumor suppressor activity in colon cancer. The aberrant methylation of RET correlates with decreased RET expression, whereas the restoration of RET in colorectal cancer cell lines results in apoptosis. Furthermore, in support of a tumor suppressor function of RET, mutant RET has also been found in primary colorectal cancer. We now show that these mutations inactivate RET, which is consistent with RET being a tumor suppressor gene in the colon. These findings suggest that the aberrant methylation of RET and the mutational inactivation of RET promote colorectal cancer formation and that RET can serve as a tumor suppressor gene in the colon. Moreover, the increased frequency of methylated RET in colon cancers compared to adenomas suggests RET inactivation is involved in the progression of colon adenomas to cancer. PMID:22751117

  14. OFFICIAL MEDICATIONS FOR ANTI-TUMOR GENE THERAPY

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    E. R. Nemtsova

    2016-01-01

    Full Text Available This is a review of modern literature data of official medications for anti-tumor gene therapy as well as of medications that finished clinical trials.The article discusses the concept of gene therapy, the statistical analysis results of initiated clinical trials of gene products, the most actively developing directions of anticancer gene therapy, and the characteristics of anti-tumor gene medications.Various delivery systems for gene material are being examined, including viruses that are defective in  replication (Gendicine™ and Advexin and oncolytic (tumor specific conditionally replicating viruses (Oncorine™, ONYX-015, Imlygic®.By now three preparations for intra-tumor injection have been introduced into oncology clinical practice: two of them – Gendicine™ and Oncorine™ have been registered in China, and one of them – Imlygic® has been registered in the USA. Gendicine™ and Oncorine™ are based on the wild type p53 gene and are designed for treatment of patients with head and neck malignancies. Replicating adenovirus is the delivery system in Gendicine™, whereas oncolytic adenovirus is the vector for gene material in Oncorine™. Imlygic® is based on the  recombinant replicating HSV1 virus with an introduced GM–CSF gene and is designed for treatment of  melanoma patients. These medications are well tolerated and do not cause any serious adverse events. Gendicine™ and Oncorine™ are not effective in monotherapy but demonstrate pronounced synergism with chemoand radiation therapy. Imlygic® has just started the post marketing trials.

  15. Novel fusion genes and chimeric transcripts in ependymal tumors.

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    Olsen, Thale Kristin; Panagopoulos, Ioannis; Gorunova, Ludmila; Micci, Francesca; Andersen, Kristin; Kilen Andersen, Hege; Meling, Torstein R; Due-Tønnessen, Bernt; Scheie, David; Heim, Sverre; Brandal, Petter

    2016-12-01

    We have previously identified two ALK rearrangements in a subset of ependymal tumors using a combination of cytogenetic data and RNA sequencing. The aim of this study was to perform an unbiased search for fusion transcripts in our entire series of ependymal tumors. Fusion analysis was performed using the FusionCatcher algorithm on 12 RNA-sequenced ependymal tumors. Candidate transcripts were prioritized based on the software's filtering and manual visualization using the BLAST (Basic Local Alignment Search Tool) and BLAT (BLAST-like alignment tool) tools. Genomic and reverse transcriptase PCR with subsequent Sanger sequencing was used to validate the potential fusions. Fluorescent in situ hybridization (FISH) using locus-specific probes was also performed. A total of 841 candidate chimeric transcripts were identified in the 12 tumors, with an average of 49 unique candidate fusions per tumor. After algorithmic and manual filtering, the final list consisted of 24 potential fusion events. Raw RNA-seq read sequences and PCR validation supports two novel fusion genes: a reciprocal fusion gene involving UQCR10 and C1orf194 in an adult spinal ependymoma and a TSPAN4-CD151 fusion gene in a pediatric infratentorial anaplastic ependymoma. Our previously reported ALK rearrangements and the RELA and YAP1 fusions found in supratentorial ependymomas were until now the only known fusion genes present in ependymal tumors. The chimeric transcripts presented here are the first to be reported in infratentorial or spinal ependymomas. Further studies are required to characterize the genomic rearrangements causing these fusion genes, as well as the frequency and functional importance of the fusions. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

  16. Wilms' tumor gene 1 (WT1) in endometrial carcinoma.

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    Coosemans, An; Moerman, Philippe; Verbist, Godelieve; Maes, Wim; Neven, Patrick; Vergote, Ignace; Van Gool, Stefaan W; Amant, Frédéric

    2008-12-01

    Wilms' tumor gene (WT1), located on chromosome 11, encodes a transcription factor that contributes to the carcinogenesis of uterine sarcomas. To expand the knowledge on the biological role of WT1 in other uterine cancers, we focused on its detection in endometrial carcinoma. In total, 36 paraffin-embedded tumors were available for WT1 immunohistochemical (IHC) analysis including endometrial endometrioid carcinoma (n=24), serous carcinoma (n=9) and clear cell carcinoma (n=3). Three slides from different sites of the tumor were analysed. Of these tumors, 32 snap frozen tissue samples were available for RT-PCR (endometrioid carcinoma (23), serous carcinoma (7) and clear cell carcinoma (2)). To compare, WT1 expression was also evaluated by IHC in benign endometrium (12) and benign endometrial polyps (5). WT1 positivity was noticed in tumor cells and endothelial cells, lining the intratumoral blood vessels. Overall, 72% (26/36) of tumors stained positive for WT1. RT-PCR results showed WT1 positivity in 75% (24/32) of samples. Comparing the staining patterns of the 3 different bioptic sites, tumor heterogeneity was demonstrated in the majority (72%) of samples. Although WT1 is expressed in a majority of endometrial carcinomas, a heterogeneous staining pattern is observed. This information is important for WT1-directed immunotherapy.

  17. Role for the Wilms tumor gene in genital development

    Energy Technology Data Exchange (ETDEWEB)

    van Heyningen, V.; Bickmore, W.A.; Seawright, A.; Fletcher, J.M.; Maule, J.; Hastie, N.D. (Western General Hospital, Edinburgh (England)); Fekete, G. (Semmelweis Univ. Medical School, Budapest (Hungary)); Gessler, M.; Bruns, G.A.P. (Harvard Medical School, Boston, MA (USA)); Huerre-Jeanpierre, C.; Junien, C. (Institut National de la Sante et de la Recherche Medicale, Paris (France)); Williams, B.R.G. (Univ. of Toronto, Ontario (Canada))

    1990-07-01

    Detailed molecular definition of the WAGR region at chromosome 11p13 has been achieved by chromosome breakpoint analysis and long-range restriction mapping. Here the authors describe the molecular detection of a cytogenetically invisible 1-megabase deletion in an individual with aniridia, cryptorchidism, and hypospadias but no Wilms tumor (WT). The region of overlap between this deletion and one associated with WT and similar genital anomalies but no aniridia covers a region of 350-400 kilobases, which is coincident with the extent of homozygous deletion detected in tumor tissue from a sporadic WT. A candidate WT gene located within this region has recently been isolated, suggesting nonpenetrance for tumor expression in the first individual. The inclusion within the overlap region of a gene for WT predisposition and a gene for the best-documented WT-associated genitourinary malformations leads to suggest that both of these anomalies result from a loss-of-function mutation at the same locus. This in turn implies that the WT gene exerts pleiotropic effect on both kidney and genitourinary development, a possibility supported by the observed expression pattern of the WT candidate gene in developing kidney and gonads.

  18. Real-time PCR analysis of genes encoding tumor antigens in esophageal tumors and a cancer vaccine

    DEFF Research Database (Denmark)

    Weinert, Brian T; Krishnadath, Kausilia K; Milano, Francesca

    2009-01-01

    Tumor antigens are the primary target of therapeutic cancer vaccines. We set out to define and compare the expression pattern of tumor antigen genes in esophagus carcinoma biopsies and in an allogeneic tumor lysate-based cancer vaccine, MelCancerVac. Cells used for vaccine production were treated...... with the DNA methyltransferase inhibitor 5-aza-2'-deoxycytidine (5-aza-CdR) to determine whether this treatment could improve the profile of tumor antigen genes expressed in these cells. In addition, the presence of MAGE-A tumor antigen protein was evaluated in the purified tumor cell lysate used...

  19. Trojan horse at cellular level for tumor gene therapies.

    Science.gov (United States)

    Collet, Guillaume; Grillon, Catherine; Nadim, Mahdi; Kieda, Claudine

    2013-08-10

    Among innovative strategies developed for cancer treatments, gene therapies stand of great interest despite their well-known limitations in targeting, delivery, toxicity or stability. The success of any given gene-therapy is highly dependent on the carrier efficiency. New approaches are often revisiting the mythic trojan horse concept to carry therapeutic nucleic acid, i.e. DNAs, RNAs or small interfering RNAs, to pathologic tumor site. Recent investigations are focusing on engineering carrying modalities to overtake the above limitations bringing new promise to cancer patients. This review describes recent advances and perspectives for gene therapies devoted to tumor treatment, taking advantage of available knowledge in biotechnology and medicine. Copyright © 2013 Elsevier B.V. All rights reserved.

  20. Molecular Imaging of Gene Expression and Efficacy following Adenoviral-Mediated Brain Tumor Gene Therapy

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    Alnawaz Rehemtulla

    2002-01-01

    Full Text Available Cancer gene therapy is an active area of research relying upon the transfer and subsequent expression of a therapeutic transgene into tumor cells in order to provide for therapeutic selectivity. Noninvasive assessment of therapeutic response and correlation of the location, magnitude, and duration of transgene expression in vivo would be particularly useful in the development of cancer gene therapy protocols by facilitating optimization of gene transfer protocols, vector development, and prodrug dosing schedules. In this study, we developed an adenoviral vector containing both the therapeutic transgene yeast cytosine deaminase (yCD along with an optical reporter gene (luciferase. Following intratumoral injection of the vector into orthotopic 9L gliomas, anatomical and diffusion-weighted MR images were obtained over time in order to provide for quantitative assessment of overall therapeutic efficacy and spatial heterogeneity of cell kill, respectively. In addition, bioluminescence images were acquired to assess the duration and magnitude of gene expression. MR images revealed significant reduction in tumor growth rates associated with yCD/5-fluorocytosine (5FC gene therapy. Significant increases in mean tumor diffusion values were also observed during treatment with 5FC. Moreover, spatial heterogeneity in tumor diffusion changes were also observed revealing that diffusion magnetic resonance imaging could detect regional therapeutic effects due to the nonuniform delivery and/or expression of the therapeutic yCD transgene within the tumor mass. In addition, in vivo bioluminescence imaging detected luciferase gene expression, which was found to decrease over time during administration of the prodrug providing a noninvasive surrogate marker for monitoring gene expression. These results demonstrate the efficacy of the yCD/5FC strategy for the treatment of brain tumors and reveal the feasibility of using multimodality molecular and functional imaging

  1. Normalization of gene expression measurements in tumor tissues: comparison of 13 endogenous control genes.

    NARCIS (Netherlands)

    Kok, J.B. de; Roelofs, R.W.; Giesendorf, B.A.J.; Pennings, J.L.; Waas, E.T.; Feuth, A.B.; Swinkels, D.W.; Span, P.N.

    2005-01-01

    For interpretation of quantitative gene expression measurements in clinical tumor samples, a normalizer is necessary to correct expression data for differences in cellular input, RNA quality, and RT efficiency between samples. In many studies, a single housekeeping gene is used for normalization.

  2. Cytokine Gene Polymorphisms in Egyptian Cases with Brain Tumors

    International Nuclear Information System (INIS)

    Badr El-Din, N.K.; Abdel-Hady, E.K.; Salem, F.K.; Settin, A.; ALI, N.

    2009-01-01

    Background: Cytokines are proposed to play important roles in brain tumor biology as well as neuro degeneration or impaired neuronal function. Objectives: This work aimed to check the association of polymorphisms of cytokine genes in Egyptian cases with brain tumors. Methods: This work included 45 cases affected by brain tumors diagnosed as 24 benign and 21 malignant. Their median age was 45 years, and they were 20 males and 25 females. These cases were taken randomly from the Neurosurgery Department of Mansoura University Hospital, Egypt. Case genotypes were compared to 98 healthy unrelated controls from the same locality. DNA was amplified using PCR utilizing sequence specific primers (SSP) for detection of polymorphisms related to TNF-a-308 (G/A), IL-10-1082 (G/A), IL-6-174 (G/C) and IL-1Ra (VNTR) genes. Results: Cases affected with benign brain tumors showed a significant higher frequency of IL-10-1082 A/A [odds ratio (OR=8.0), p<0.001] and IL-6-174 C/C (OR=6.3, p=0.002) homozygous genotypes as compared to controls. Malignant cases, on the other hand, showed significantly higher frequency of IL-6-174 C/C (OR =4.8, p=0.002) homozygous genotype and TNF-a-308 A/A (OR=4.9, p<0.001) homozygous genotype when compared to controls. In the meantime, all cases showed no significant difference regarding the distribution of IL-1Ra VNTR genotype polymorphism compared to controls. Conclusions: Cytokine gene polymorphisms showed a pattern of association with brain tumors which may have potential impact on family counseling and disease management.

  3. Molecular genetic analysis of tumor suppressor genes in ovarian cancer

    International Nuclear Information System (INIS)

    Lee, Je Ho; Park, Sang Yun

    1992-04-01

    To examine the loci of putative tumor suppressor genes in ovarian cancers, we performed the molecular genetic analysis with fresh human ovarian cancers and observed the following data. Frequent allelic losses were observed on chromosomes 4p(42%), 6p(50%), 7p(43%), 8q(31%), 12p(38%), 12q(33%), 16p(33%), 16q(37%), and 19p(34%) in addition to the previously reported 6q, 11p, and 17p in ovarian caroinomas. we have used an additional probe, TCP10 to narrow down the deleted region on chromosome 6q. TCP10 was reported to be mapped to 6q 25-27. Allelic loss was found to be 40% in epithelial ovarian caroinomas. This finding suggests that chromosome 6q 24-27 is one of putative region haboring the tumor suppressor gene of epithelial ovarian cancer (particularly serous type). To examine the association between FAL(Fractional Allelic Loss) and histopathological features, the FAL value on each phenotypically different tumor was calculated as the ratio of the number of allelic losses versus the number of cases informative in each chromosomal arm. The average FALs for each phenotypically different tumor were: serous cystoadenocarcinomas. FAL=0.31 : mucinous 0.12 : and clear cell carcinoma. FAL=0.20. (Author)

  4. Gene therapy for patients with advanced solid tumors

    DEFF Research Database (Denmark)

    Spanggaard, Iben; Dahlstroem, Karin; Laessoee, Line

    2017-01-01

    BACKGROUND: Gene electrotrotransfer describes the use of electric pulses to transfer DNA to cells. Particularly skeletal muscle has potential for systemic secretion of therapeutic proteins. Gene electrotransfer to muscle using the integrin inhibitor plasmid AMEP (Antiangiogenic MEtargidin Peptide......) was investigated in a phase I dose escalation study. Primary objective was safety. MATERIAL AND METHODS: Patients with metastatic or locally advanced solid tumors, without further standard treatments available, were treated with once-only gene electrotransfer of plasmid AMEP to the femoral muscle. Safety...... not be detected, which could be due to the limit of detection. No objective responses were seen. CONCLUSIONS: Gene electrotransfer of plasmid AMEP was found to be safe and tolerable. No objective responses were observed but other DNA drugs may be tested in the future using this procedure....

  5. Histone deacetylase regulation of immune gene expression in tumor cells

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    Tomasi, Thomas B.

    2011-01-01

    Epigenetic modifications of chromatin, such as histone acetylation, are involved in repression of tumor antigens and multiple immune genes that are thought to facilitate tumor escape. The status of acetylation in a cell is determined by the balance of the activities of histone acetyltransferases and histone deacetylases. Inhibitors of histone deacetylase (HDACi) can enhance the expression of immunologically important molecules in tumor cells and HDACi treated tumor cells are able to induce immune responses in vitro and in vivo. Systemic HDACi are in clinical trails in cancer and also being used in several autoimmune disease models. To date, 18 HDACs have been reported in human cells and more than thirty HDACi identified, although only a few immune targets of these inhibitors have been identified. Here, we discuss the molecular pathways employed by HDACi and their potential role in inducing immune responses against tumors. We review data suggesting that selection of target specific HDACi and combinations with other agents and modalities, including those that activate stress pathways, may further enhance the efficacy of epigenetic therapies. PMID:18213528

  6. Combining Oncolytic Virotherapy with p53 Tumor Suppressor Gene Therapy

    Directory of Open Access Journals (Sweden)

    Christian Bressy

    2017-06-01

    Full Text Available Oncolytic virus (OV therapy utilizes replication-competent viruses to kill cancer cells, leaving non-malignant cells unharmed. With the first U.S. Food and Drug Administration-approved OV, dozens of clinical trials ongoing, and an abundance of translational research in the field, OV therapy is poised to be one of the leading treatments for cancer. A number of recombinant OVs expressing a transgene for p53 (TP53 or another p53 family member (TP63 or TP73 were engineered with the goal of generating more potent OVs that function synergistically with host immunity and/or other therapies to reduce or eliminate tumor burden. Such transgenes have proven effective at improving OV therapies, and basic research has shown mechanisms of p53-mediated enhancement of OV therapy, provided optimized p53 transgenes, explored drug-OV combinational treatments, and challenged canonical roles for p53 in virus-host interactions and tumor suppression. This review summarizes studies combining p53 gene therapy with replication-competent OV therapy, reviews preclinical and clinical studies with replication-deficient gene therapy vectors expressing p53 transgene, examines how wild-type p53 and p53 modifications affect OV replication and anti-tumor effects of OV therapy, and explores future directions for rational design of OV therapy combined with p53 gene therapy.

  7. Alternative polyadenylation of tumor suppressor genes in small intestinal neuroendocrine tumors

    DEFF Research Database (Denmark)

    Rehfeld, Anders Aagaard; Plass, Mireya; Døssing, Kristina

    2014-01-01

    The tumorigenesis of small intestinal neuroendocrine tumors (SI-NETs) is poorly understood. Recent studies have associated alternative polyadenylation (APA) with proliferation, cell transformation, and cancer. Polyadenylation is the process in which the pre-messenger RNA is cleaved at a polyA site...... and a polyA tail is added. Genes with two or more polyA sites can undergo APA. This produces two or more distinct mRNA isoforms with different 3' untranslated regions. Additionally, APA can also produce mRNAs containing different 3'-terminal coding regions. Therefore, APA alters both the repertoire...... and the expression level of proteins. Here, we used high-throughput sequencing data to map polyA sites and characterize polyadenylation genome-wide in three SI-NETs and a reference sample. In the tumors, 16 genes showed significant changes of APA pattern, which lead to either the 3' truncation of mRNA coding regions...

  8. Tissue elasticity regulated tumor gene expression: implication for diagnostic biomarkers of primitive neuroectodermal tumor.

    Directory of Open Access Journals (Sweden)

    Long T Vu

    Full Text Available The tumor microenvironment consists of both physical and chemical factors. Tissue elasticity is one physical factor contributing to the microenvironment of tumor cells. To test the importance of tissue elasticity in cell culture, primitive neuroectodermal tumor (PNET stem cells were cultured on soft polyacrylamide (PAA hydrogel plates that mimics the elasticity of brain tissue compared with PNET on standard polystyrene (PS plates. We report the molecular profiles of PNET grown on either PAA or PS.A whole-genome microarray profile of transcriptional expression between the two culture conditions was performed as a way to probe effects of substrate on cell behavior in culture. The results showed more genes downregulated on PAA compared to PS. This led us to propose microRNA (miRNA silencing as a potential mechanism for downregulation. Bioinformatic analysis predicted a greater number of miRNA binding sites from the 3' UTR of downregulated genes and identified as specific miRNA binding sites that were enriched when cells were grown on PAA-this supports the hypothesis that tissue elasticity plays a role in influencing miRNA expression. Thus, Dicer was examined to determine if miRNA processing was affected by tissue elasticity. Dicer genes were downregulated on PAA and had multiple predicted miRNA binding sites in its 3' UTR that matched the miRNA binding sites found enriched on PAA. Many differentially regulated genes were found to be present on PS but downregulated on PAA were mapped onto intron sequences. This suggests expression of alternative polyadenylation sites within intron regions that provide alternative 3' UTRs and alternative miRNA binding sites. This results in tissue specific transcriptional downregulation of mRNA in humans by miRNA. We propose a mechanism, driven by the physical characteristics of the microenvironment by which downregulation of genes occur. We found that tissue elasticity-mediated cytokines (TGFβ2 and TNFα signaling

  9. p53 tumor suppressor gene: significance in neoplasia - a review

    International Nuclear Information System (INIS)

    Alam, J.M.

    2000-01-01

    p53 is a tumor suppressor gene located on chromosome 17p13.1. Its function includes cell cycle control and apoptosis. Loss of p53 function, either due to decreased level or genetic transformation, is associated with loss of cell cycle control, decrease, apoptosis and genomic modification, such mutation of p53 gene is now assessed and the indicator of neoplasia of cancer of several organs and cell types, p53 has demonstrated to have critical role in defining various progressive stages of neoplasia, therapeutic strategies and clinical application. The present review briefly describes function of p53 in addition to its diagnostic and prognostic significance in detecting several types of neoplasia. (author)

  10. Classical Oncogenes and Tumor Suppressor Genes: A Comparative Genomics Perspective

    Directory of Open Access Journals (Sweden)

    Oxana K. Pickeral

    2000-05-01

    Full Text Available We have curated a reference set of cancer-related genes and reanalyzed their sequences in the light of molecular information and resources that have become available since they were first cloned. Homology studies were carried out for human oncogenes and tumor suppressors, compared with the complete proteome of the nematode, Caenorhabditis elegans, and partial proteomes of mouse and rat and the fruit fly, Drosophila melanogaster. Our results demonstrate that simple, semi-automated bioinformatics approaches to identifying putative functionally equivalent gene products in different organisms may often be misleading. An electronic supplement to this article1 provides an integrated view of our comparative genomics analysis as well as mapping data, physical cDNA resources and links to published literature and reviews, thus creating a “window” into the genomes of humans and other organisms for cancer biology.

  11. Epigenetic silencing of tumor suppressor genes: Paradigms, puzzles, and potential.

    Science.gov (United States)

    Kazanets, Anna; Shorstova, Tatiana; Hilmi, Khalid; Marques, Maud; Witcher, Michael

    2016-04-01

    Cancer constitutes a set of diseases with heterogeneous molecular pathologies. However, there are a number of universal aberrations common to all cancers, one of these being the epigenetic silencing of tumor suppressor genes (TSGs). The silencing of TSGs is thought to be an early, driving event in the oncogenic process. With this in consideration, great efforts have been made to develop small molecules aimed at the restoration of TSGs in order to limit tumor cell proliferation and survival. However, the molecular forces that drive the broad epigenetic reprogramming and transcriptional repression of these genes remain ill-defined. Undoubtedly, understanding the molecular underpinnings of transcriptionally silenced TSGs will aid us in our ability to reactivate these key anti-cancer targets. Here, we describe what we consider to be the five most logical molecular mechanisms that may account for this widely observed phenomenon: 1) ablation of transcription factor binding, 2) overexpression of DNA methyltransferases, 3) disruption of CTCF binding, 4) elevation of EZH2 activity, 5) aberrant expression of long non-coding RNAs. The strengths and weaknesses of each proposed mechanism is highlighted, followed by an overview of clinical efforts to target these processes. Copyright © 2016 The Authors. Published by Elsevier B.V. All rights reserved.

  12. A novel splice mutation in the TP53 gene associated with Leydig cell tumor and primitive neuroectodermal tumor

    DEFF Research Database (Denmark)

    Stecher, Chalotte Willemann; Grønbaek, Kirsten; Hasle, Henrik

    2008-01-01

    A 20-month-old boy presented with precocious puberty due to a Leydig cell tumor, and at the age of 6 years with a primitive neuroectodermal brain-tumor (PNET). A novel splice site mutation of the TP53-gene, likely to be associated with a nonfunctional protein, was found in the proband, his father...

  13. Tumorer

    DEFF Research Database (Denmark)

    Prause, J.U.; Heegaard, S.

    2005-01-01

    oftalmologi, øjenlågstumorer, conjunctivale tumorer, malignt melanom, retinoblastom, orbitale tumorer......oftalmologi, øjenlågstumorer, conjunctivale tumorer, malignt melanom, retinoblastom, orbitale tumorer...

  14. Methylation of Tumor Suppressor Genes in Autoimmune Pancreatitis.

    Science.gov (United States)

    Kinugawa, Yasuhiro; Uehara, Takeshi; Sano, Kenji; Matsuda, Kazuyuki; Maruyama, Yasuhiro; Kobayashi, Yukihiro; Nakajima, Tomoyuki; Hamano, Hideaki; Kawa, Shigeyuki; Higuchi, Kayoko; Hosaka, Noriko; Shiozawa, Satoshi; Ishigame, Hiroki; Ota, Hiroyoshi

    Autoimmune pancreatitis (AIP) is a representative IgG4-related and inflammatory disease of unknown etiology. To clarify mechanisms of carcinogenesis resulting from AIP, we focused on methylation abnormalities and KRAS mutations in AIP. Six tumor suppressor genes (NPTX2, Cyclin D2, FOXE1, TFPI2, ppENK, and p16) that exhibited hypermethylation in pancreatic carcinoma were selected for quantitative SYBR green methylation-specific polymerase chain reaction in 10 AIP specimens, 10 pancreatic adenocarcinoma cases without history of AIP containing carcinoma areas (CAs) and noncarcinoma areas (NCAs), and 11 normal pancreas (NP) samples. KRAS mutation in codons 12, 13, and 61 were also investigated using direct sequencing. Hypermethylation events (≥10%) were identified in NPTX2, Cyclin D2, FOXE1, TFPI2, ppENK, and p16 in 1, 2, 2, 0, 2, and 0 CA cases, respectively, but not in these 6 candidate genes in AIP, NCA, and NP. However, the TFPI2 methylation ratio was significantly higher in AIP than NCA and NP. Direct sequencing results for KRAS showed no single-point mutations in AIP. These are the first studies characterizing methylation abnormalities in AIP. AIP's inflammatory condition may be related to carcinogenesis. Further study will elucidate methylation abnormalities associated with carcinogenesis in AIP.

  15. The progress of tumor gene-radiotherapy induced by Egr-1 promoter

    International Nuclear Information System (INIS)

    Guo Rui; Li Biao

    2010-01-01

    The promoter of early growth response gene-1 (Egr-1) is a cis-acting element of Egr-1, and its activity is regulated by inducers such as ionizing radiation, free radical. In designated gene-radiotherapy system, radiation combined with therapeutic gene (such as tumor necrosis factor-α gene, suicide gene) can spatially and temporally regulate therapeutic gene expression in the irradiated field, produced a marked effect, while little systemic toxicities were observed. The combination of radiotherapy and gene therapy is promising in tumor therapy. (authors)

  16. [Correlation analysis of G870A CCND1 gene polymorphism with digestive system tumors].

    Science.gov (United States)

    Yang, Shu-Min; Shi, Ya-Lin

    2016-11-20

    To study the correlation of G870A CCND1 gene polymorphism and digestive system tumors. From August 2010 to August 2014, 164 digestive system cancer patients (including 82 patients with gastric cancer and 82 with colorectal cancer) and 82 healthy subjects (control group) were examined with PCR-restriction fragment length polymorphism (PCR-RFLP). The distribution of CCND1 gene G870A frequency in the 3 groups and its association with tumor staging and grading were analyzed. The frequencies of the GG, GA and AA genotypes in G870A CCND1 gene loci in patients with gastric cancer and colorectal cancer differed significantly from those in the control group (Pdigestive system tumors (Pdigestive system cancer risk than the GG genotype (Pdigestive system tumors. The allele A is associated with an increased risk of digestive system tumors and correlated with the tumor differentiation and staging of the tumor.

  17. Tumoral Environment Triggers Transcript Anomalies in Established Tumors: Induction of Altered Gene Expression and of Aberrant, Truncated and B2 Repeat-Containing Gene Transcripts

    Directory of Open Access Journals (Sweden)

    Pieter Rottiers

    1999-12-01

    Full Text Available In addition to eugenetic changes, cancerous cells exhibit extensive modifications in the expression levels of a variety of genes. The phenotypic switch observed after inoculation of T lymphoma cells into syngenic mice illustrates the active participation of tumoral environment in the induction of an aberrant gene expression pattern. To further substantiate this contribution, we performed polymerase chain reaction (PCR-based subtraction suppression hybridization (SSH to identify genes that are differentially expressed in tumor-derived EL4/13.3 cells compared to the same cells isolated from cultures. Besides a number of unknown genes, the subtracted library contained several known genes that have been reported to be expressed at increased levels in tumors and/or to contribute to carcinogenesis. Apart from clones representing translated transcripts, the subtracted library also contained a high number of clones representing B2 repeat elements, viz. short interspersed repetitive elements that are transcribed by RNA polymerase III. Northern blotting confirmed the induction of B2 transcripts in tumor tissue and also revealed induction of chimeric, B2 repeat-containing mRNA. The appearance of chimeric transcripts was accompanied by aberrant, shorter-than-full-length transcripts, specifically from upregulated genes. Accordingly, in addition to altered gene expression, tumoral environmental triggers constitute a potent mechanism to create an epigenetic diversity in cancers by inducing extensive transcript anomalies.

  18. The common mechanisms of transformation by the small DNA tumor viruses: The inactivation of tumor suppressor gene products: p53.

    Science.gov (United States)

    Levine, Arnold J

    2009-02-20

    The small DNA tumor viruses, Polyoma virus, Simian Vacuolating Virus 40, the Papilloma viruses and the human Adenoviruses, were first described during a period of intense virus discovery (1930-1960s) and shown to produce tumors in animals. In each of these cases the viral DNA was shown to persist (commonly integrated into a host chromosome) and only a selected portion of this DNA was expressed as m-RNA and proteins in these cancers. The viral encoded tumor antigens were identified and shown to be required to both establish the tumor and maintain the transformed cell phenotype. The functions of these viral tumor antigens were explored and shown to have common features and mechanisms even though they appear to have evolved from diverse genes. The SV40 large tumor antigen, the human Papilloma virus E7 protein and the Adenovirus E1A protein were shown to bind to and inactivate the functions of the Retinoblastoma proteins in transformed cells. This resulted in the activation of the E2F and DP transcription factors and the entry of cells into the S-phase of DNA synthesis which was required for viral DNA replication. These events triggered the activation of p53 which promotes apoptosis of these virus infected cells limiting virus replication and tumor formation. These viruses responded by evolving and producing the SV40 large tumor antigen, the human Papilloma virus E6 protein and the Adenovirus E1b-55Kd protein which binds to and inactivates the p53 functions in both the infected cells and transformed cells. Some of the human Papilloma viruses and one of the Polyoma viruses have been shown to cause selected cancers in humans. Both the p53 tumor suppressor gene, which was uncovered in the studies with these viruses, and the retinoblastoma protein, have been shown to play a central role in the origins of human cancers via both somatic and germ line mutations in those genes.

  19. The wild type p53 gene radiosensitizes malignant cells and tumors

    International Nuclear Information System (INIS)

    Gallardo, David; McBride, William

    1996-01-01

    Purpose/Objective: To investigate the use of the wild-type p53 gene as a radiosensitizer of human malignant cells and tumors. Materials and Methods: An ovarian carcinoma cell line (SKOV) lacking the p53 gene was transfected in vitro with E1 deleted adenovirus containing the wild type p53 gene (Ad/p53). SKOV cells expressing the p53 protein were tested for intrinsic radiosensitivity with clonogenic survival assays. SKOV tumors growing in the flanks of SCID mice were injected with 1x10(9) PFU of Ad/p53 or Ad/luciferase. Injected tumors were either irradiated to 24 Gy in 4 Gy fractions or not irradiated. Tumor diameters were then monitored. Results: Cells expressing the p53 gene product were more sensitive to radiation than control cells expressing the luciferase gene in in vitro clonogenic survival assays. SKOV tumors injected with the Ad/p53 virus expressed the p53 protein as demonstrated through immunohistochemical analysis. Tumors injected with Ad/p53 grew more slowly than tumors injected with Ad/luciferase or saline. After irradiation with 24Gy, tumors injected with Ad/p53 were controlled while those injected with Ad/luciferase were not. Conclusions: Our results formally demonstrate that transfer of the wild-type p53 gene can increase the intrinsic radiation sensitivity of a malignant cell line lacking the p53 gene. We also demonstrate that intra-tumoral injection of an adenoviral vector containing the wild type p53 gene increases the radiation responsiveness of established tumors, consistent with the radiosensitizing activity of the wild type p53 gene demonstrated in vitro. These studies support clinical trials using p53 gene transfer to potentially improve the efficacy of radiation therapy in human malignancies

  20. The effect of endostatin gene in combination with radiotherapy on rats with implanted tumor

    International Nuclear Information System (INIS)

    Li Yong; Jin Ning; Yang Haishan; Piao Chunji; Lv Zhe

    2005-01-01

    Objective: To study the combination therapy effect of the radiotherapy with endostatin gene therapy on the rats with implanted tumor. Methods: Immediate Walker-256 cancerous ascetic injection method was used to make a rat tumor-bearing model, then the tumor was treated with saline, endostatin gene, irradiation or endostatin gene plus irradiation. The tumor growth rate and weight were observed, Western blot and RT-PCR were adopted to check the expressions of endostatin mRNA and protein. Results: The expressions of endostatin mRNA and protein were significant in the gene therapy group and the gene plus radiotherapy group, but there was a significant difference between these two groups. As compared with the control group, the tumor growth rate and weight decreased significantly in all the therapy groups (P 0.05). Conclusion: After the pCMV-Endostatin was induced, the expressions of endostatin mRNA and protein was significant in Walker-256 tumor and the tumor growth was inhibited. However, the effect of the endostatin gene plus radiotherapy was obviously better than that of the endostatin gene therapy group or the radiotherapy group for inhibiting tumor growth. (authors)

  1. Microenvironment alters epigenetic and gene expression profiles in Swarm rat chondrosarcoma tumors

    Directory of Open Access Journals (Sweden)

    Hamm Christopher A

    2010-09-01

    Full Text Available Abstract Background Chondrosarcomas are malignant cartilage tumors that do not respond to traditional chemotherapy or radiation. The 5-year survival rate of histologic grade III chondrosarcoma is less than 30%. An animal model of chondrosarcoma has been established - namely, the Swarm Rat Chondrosarcoma (SRC - and shown to resemble the human disease. Previous studies with this model revealed that tumor microenvironment could significantly influence chondrosarcoma malignancy. Methods To examine the effect of the microenvironment, SRC tumors were initiated at different transplantation sites. Pyrosequencing assays were utilized to assess the DNA methylation of the tumors, and SAGE libraries were constructed and sequenced to determine the gene expression profiles of the tumors. Based on the gene expression analysis, subsequent functional assays were designed to determine the relevancy of the specific genes in the development and progression of the SRC. Results The site of transplantation had a significant impact on the epigenetic and gene expression profiles of SRC tumors. Our analyses revealed that SRC tumors were hypomethylated compared to control tissue, and that tumors at each transplantation site had a unique expression profile. Subsequent functional analysis of differentially expressed genes, albeit preliminary, provided some insight into the role that thymosin-β4, c-fos, and CTGF may play in chondrosarcoma development and progression. Conclusion This report describes the first global molecular characterization of the SRC model, and it demonstrates that the tumor microenvironment can induce epigenetic alterations and changes in gene expression in the SRC tumors. We documented changes in gene expression that accompany changes in tumor phenotype, and these gene expression changes provide insight into the pathways that may play a role in the development and progression of chondrosarcoma. Furthermore, specific functional analysis indicates that

  2. Microenvironment alters epigenetic and gene expression profiles in Swarm rat chondrosarcoma tumors

    International Nuclear Information System (INIS)

    Hamm, Christopher A; Wang, Deli; Malchenko, Sergey; Fatima Bonaldo, Maria de; Casavant, Thomas L; Hendrix, Mary JC; Soares, Marcelo B; Stevens, Jeff W; Xie, Hehuang; Vanin, Elio F; Morcuende, Jose A; Abdulkawy, Hakeem; Seftor, Elisabeth A; Sredni, Simone T; Bischof, Jared M

    2010-01-01

    Chondrosarcomas are malignant cartilage tumors that do not respond to traditional chemotherapy or radiation. The 5-year survival rate of histologic grade III chondrosarcoma is less than 30%. An animal model of chondrosarcoma has been established - namely, the Swarm Rat Chondrosarcoma (SRC) - and shown to resemble the human disease. Previous studies with this model revealed that tumor microenvironment could significantly influence chondrosarcoma malignancy. To examine the effect of the microenvironment, SRC tumors were initiated at different transplantation sites. Pyrosequencing assays were utilized to assess the DNA methylation of the tumors, and SAGE libraries were constructed and sequenced to determine the gene expression profiles of the tumors. Based on the gene expression analysis, subsequent functional assays were designed to determine the relevancy of the specific genes in the development and progression of the SRC. The site of transplantation had a significant impact on the epigenetic and gene expression profiles of SRC tumors. Our analyses revealed that SRC tumors were hypomethylated compared to control tissue, and that tumors at each transplantation site had a unique expression profile. Subsequent functional analysis of differentially expressed genes, albeit preliminary, provided some insight into the role that thymosin-β4, c-fos, and CTGF may play in chondrosarcoma development and progression. This report describes the first global molecular characterization of the SRC model, and it demonstrates that the tumor microenvironment can induce epigenetic alterations and changes in gene expression in the SRC tumors. We documented changes in gene expression that accompany changes in tumor phenotype, and these gene expression changes provide insight into the pathways that may play a role in the development and progression of chondrosarcoma. Furthermore, specific functional analysis indicates that thymosin-β4 may have a role in chondrosarcoma metastasis

  3. Cellular senescence and tumor suppressor gene p16.

    Science.gov (United States)

    Rayess, Hani; Wang, Marilene B; Srivatsan, Eri S

    2012-04-15

    Cellular senescence is an irreversible arrest of cell growth. Biochemical and morphological changes occur during cellular senescence, including the formation of a unique cellular morphology such as flattened cytoplasm. Function of mitochondria, endoplasmic reticulum and lysosomes are affected resulting in the inhibition of lysosomal and proteosomal pathways. Cellular senescence can be triggered by a number of factors including, aging, DNA damage, oncogene activation and oxidative stress. While the molecular mechanism of senescence involves p16 and p53 tumor suppressor genes and telomere shortening, this review is focused on the mechanism of p16 control. The p16-mediated senescence acts through the retinoblastoma (Rb) pathway inhibiting the action of the cyclin dependant kinases leading to G1 cell cycle arrest. Rb is maintained in a hypophosphorylated state resulting in the inhibition of transcription factor E2F1. Regulation of p16 expression is complex and involves epigenetic control and multiple transcription factors. PRC1 (Pombe repressor complex (1) and PRC2 (Pombe repressor complex (2) proteins and histone deacetylases play an important role in the promoter hypermethylation for suppressing p16 expression. While transcription factors YY1 and Id1 suppress p16 expression, transcription factors CTCF, Sp1 and Ets family members activate p16 transcription. Senescence occurs with the inactivation of suppressor elements leading to the enhanced expression of p16. Copyright © 2011 UICC.

  4. Characterization of the tumor suppressor gene WWOX in primary human oral squamous cell carcinomas

    Science.gov (United States)

    Pimenta, Flávio J.; Gomes, Dawidson A.; Perdigão, Paolla F.; Barbosa, Alvimar A.; Romano-Silva, Marco A.; Gomez, Marcus V.; Aldaz, C. Marcelo; De Marco, Luiz; Gomez, Ricardo S.

    2014-01-01

    Oral squamous cell carcinoma (OSCC) is the most common malignant neoplasm of the oral cavity, representing ~90% of all oral carcinomas and accounting for 3–5% of all malignancies. The WWOX gene (WW-domain containing oxidoreductase) is a candidate tumor suppressor gene located at 16q23.3–24.1, spanning the second most common fragile site, FRA16D. In this report, the role of the WWOX gene was investigated in 20 tumors and 10 normal oral mucosas, and we demonstrated an altered WWOX gene in 50% (10/20) of OSCCs. Using nested RT-PCR, mRNA transcription was altered in 35% of the tumors, with the complete absence of transcripts in 2 samples as well as absence of exons 6–8 (2 tumors), exon 7 (1 tumor), exon 7 and exon 6–8 (1 tumor) and partial loss of exons 8 and 9 (1 tumor). To determine if the aberrant transcripts were translated, Western blots were performed in all samples; however, only the normal protein was detected. By immunohistochemistry, a reduction in Wwox protein expression was observed, affecting 40% of the tumors when compared with normal mucosa. In addition, a novel somatic mutation (S329F) was found. The presence of alterations in mRNA transcription correlated with the reduced expression of Wwox protein in the tumors. These results show that the WWOX gene is frequently altered in OSCC and may contribute to the carcinogenesis processes in oral cancer. PMID:16152610

  5. MDM2 SNP309, gene-gene interaction, and tumor susceptibility: an updated meta-analysis

    Directory of Open Access Journals (Sweden)

    Wu Wei

    2011-05-01

    Full Text Available Abstract Background The tumor suppressor gene p53 is involved in multiple cellular pathways including apoptosis, transcriptional control, and cell cycle regulation. In the last decade it has been demonstrated that the single nucleotide polymorphism (SNP at codon 72 of the p53 gene is associated with the risk for development of various neoplasms. MDM2 SNP309 is a single nucleotide T to G polymorphism located in the MDM2 gene promoter. From the time that this well-characterized functional polymorphism was identified, a variety of case-control studies have been published that investigate the possible association between MDM2 SNP309 and cancer risk. However, the results of the published studies, as well as the subsequent meta-analyses, remain contradictory. Methods To investigate whether currently published epidemiological studies can clarify the potential interaction between MDM2 SNP309 and the functional genetic variant in p53 codon72 (Arg72Pro and p53 mutation status, we performed a meta-analysis of the risk estimate on 27,813 cases with various tumor types and 30,295 controls. Results The data we reviewed indicated that variant homozygote 309GG and heterozygote 309TG were associated with a significant increased risk of all tumor types (homozygote comparison: odds ratio (OR = 1.25, 95% confidence interval (CI = 1.13-1.37; heterozygote comparison: OR = 1.10, 95% CI = 1.03-1.17. We also found that the combination of GG and Pro/Pro, TG and Pro/Pro, GG and Arg/Arg significantly increased the risk of cancer (OR = 3.38, 95% CI = 1.77-6.47; OR = 1.88, 95% CI = 1.26-2.81; OR = 1.96, 95% CI = 1.01-3.78, respectively. In a stratified analysis by tumor location, we also found a significant increased risk in brain, liver, stomach and uterus cancer (OR = 1.47, 95% CI = 1.06-2.03; OR = 2.24, 95%CI = 1.57-3.18; OR = 1.54, 95%CI = 1.04-2.29; OR = 1.34, 95%CI = 1.07-1.29, respectively. However, no association was seen between MDM2 SNP309 and tumor susceptibility

  6. MDM2 SNP309, gene-gene interaction, and tumor susceptibility: an updated meta-analysis

    International Nuclear Information System (INIS)

    Wan, Yan; Wu, Wei; Yin, Zhihua; Guan, Peng; Zhou, Baosen

    2011-01-01

    The tumor suppressor gene p53 is involved in multiple cellular pathways including apoptosis, transcriptional control, and cell cycle regulation. In the last decade it has been demonstrated that the single nucleotide polymorphism (SNP) at codon 72 of the p53 gene is associated with the risk for development of various neoplasms. MDM2 SNP309 is a single nucleotide T to G polymorphism located in the MDM2 gene promoter. From the time that this well-characterized functional polymorphism was identified, a variety of case-control studies have been published that investigate the possible association between MDM2 SNP309 and cancer risk. However, the results of the published studies, as well as the subsequent meta-analyses, remain contradictory. To investigate whether currently published epidemiological studies can clarify the potential interaction between MDM2 SNP309 and the functional genetic variant in p53 codon72 (Arg72Pro) and p53 mutation status, we performed a meta-analysis of the risk estimate on 27,813 cases with various tumor types and 30,295 controls. The data we reviewed indicated that variant homozygote 309GG and heterozygote 309TG were associated with a significant increased risk of all tumor types (homozygote comparison: odds ratio (OR) = 1.25, 95% confidence interval (CI) = 1.13-1.37; heterozygote comparison: OR = 1.10, 95% CI = 1.03-1.17). We also found that the combination of GG and Pro/Pro, TG and Pro/Pro, GG and Arg/Arg significantly increased the risk of cancer (OR = 3.38, 95% CI = 1.77-6.47; OR = 1.88, 95% CI = 1.26-2.81; OR = 1.96, 95% CI = 1.01-3.78, respectively). In a stratified analysis by tumor location, we also found a significant increased risk in brain, liver, stomach and uterus cancer (OR = 1.47, 95% CI = 1.06-2.03; OR = 2.24, 95%CI = 1.57-3.18; OR = 1.54, 95%CI = 1.04-2.29; OR = 1.34, 95%CI = 1.07-1.29, respectively). However, no association was seen between MDM2 SNP309 and tumor susceptibility in the stratified analysis by p53 mutation status

  7. Applying unmixing to gene expression data for tumor phylogeny inference

    Directory of Open Access Journals (Sweden)

    Shackney Stanley E

    2010-01-01

    Full Text Available Abstract Background While in principle a seemingly infinite variety of combinations of mutations could result in tumor development, in practice it appears that most human cancers fall into a relatively small number of "sub-types," each characterized a roughly equivalent sequence of mutations by which it progresses in different patients. There is currently great interest in identifying the common sub-types and applying them to the development of diagnostics or therapeutics. Phylogenetic methods have shown great promise for inferring common patterns of tumor progression, but suffer from limits of the technologies available for assaying differences between and within tumors. One approach to tumor phylogenetics uses differences between single cells within tumors, gaining valuable information about intra-tumor heterogeneity but allowing only a few markers per cell. An alternative approach uses tissue-wide measures of whole tumors to provide a detailed picture of averaged tumor state but at the cost of losing information about intra-tumor heterogeneity. Results The present work applies "unmixing" methods, which separate complex data sets into combinations of simpler components, to attempt to gain advantages of both tissue-wide and single-cell approaches to cancer phylogenetics. We develop an unmixing method to infer recurring cell states from microarray measurements of tumor populations and use the inferred mixtures of states in individual tumors to identify possible evolutionary relationships among tumor cells. Validation on simulated data shows the method can accurately separate small numbers of cell states and infer phylogenetic relationships among them. Application to a lung cancer dataset shows that the method can identify cell states corresponding to common lung tumor types and suggest possible evolutionary relationships among them that show good correspondence with our current understanding of lung tumor development. Conclusions Unmixing

  8. Application Progress of CRISPR/Cas9 System for Gene Editing in Tumor Research

    Directory of Open Access Journals (Sweden)

    Chao LIU

    2015-09-01

    Full Text Available TCRISPR/Cas9 (Clustered Regularly Interspaced Short Palindromic Repeat/CRISPR-associated nuclease 9 gene editing system is a new type of gene editing technology developed based on the immune mechanism of archaea resisting the invasion of exogenous nucleic acid. Compared with traditional gene editing system, CRISPR/Cas9 system is more efficient, easier operating, and less cytotoxic. Currently, CRISPR/Cas9 gene editing technology has been applied to many aspects of cancer research, including research on cancer genes, constructing animal tumor models, screening tumor resistance-associated and phenotypic-related genes and cancer gene therapy. In this review, the application of the CRISPR/Cas9 system in tumor research were introduced.

  9. The potential for tumor suppressor gene therapy in head and neck cancer.

    Science.gov (United States)

    Birkeland, Andrew C; Ludwig, Megan L; Spector, Matthew E; Brenner, J Chad

    2016-01-01

    Head and neck squamous cell carcinoma remains a highly morbid and fatal disease. Importantly, genomic sequencing of head and neck cancers has identified frequent mutations in tumor suppressor genes. While targeted therapeutics increasingly are being investigated in head and neck cancer, the majority of these agents are against overactive/overexpressed oncogenes. Therapy to restore lost tumor suppressor gene function remains a key and under-addressed niche in trials for head and neck cancer. Recent advances in gene editing have captured the interest of both the scientific community and the public. As our technology for gene editing and gene expression modulation improves, addressing lost tumor suppressor gene function in head and neck cancers is becoming a reality. This review will summarize new techniques, challenges to implementation, future directions, and ethical ramifications of gene therapy in head and neck cancer.

  10. Molecular characteristics of mismatch repair genes in sporadic colorectal tumors in Czech patients.

    Science.gov (United States)

    Vymetalkova, Veronika Polakova; Slyskova, Jana; Korenkova, Vlasta; Bielik, Ludovit; Langerova, Lucie; Prochazka, Pavel; Rejhova, Alexandra; Schwarzova, Lucie; Pardini, Barbara; Naccarati, Alessio; Vodicka, Pavel

    2014-01-31

    Mismatch repair (MMR) genes are known to be frequently altered in colorectal cancer (CRC). Both genetics and epigenetics modifications seems to be relevant in this phenomenon, however it is still not clear how these two aspects are interconnected. The present study aimed at characterizing of epigenetic and gene expression profiles of MMR genes in sporadic CRC patients from the Czech Republic, a country with one of the highest incidences of this cancer all over Europe. Expression levels and CpG promoter methylation status of all MMR genes were evaluated in DNA from tumor and adjacent mucosal samples of 53 incident CRC patients. We have found significantly increased transcription levels in EXO1 gene in tumor tissues (P = 0.05) and significant over-expression of MSH3 gene in colon tumors when compared to adjacent mucosal tissues (P = 0.02). Interestingly, almost all MMR genes were differently expressed when localization of tumors was compared. In particular, colon tumors showed an up-regulation of EXO1, MSH2, MSH3, MSH6, and PMS2 genes in comparison to rectal tumors (P = 0.02). Expression levels of all MMR genes positively correlated between each other. The promoter methylation of MLH1 gene was observed in 9% of CRC tissues only. In our study, we have observed different pattern of MMR genes expression according to tumor localization. However, a lack of association between methylation in MMR genes and their corresponding expressions was noticed in this study, the relationship between these two aspects is worthy to be analyzed in larger population studies and in pre-malignant stages.

  11. Experimental study on anti-tumor effect of pcEgr-IFNγ gene-radiotherapy

    International Nuclear Information System (INIS)

    Wu Congmei; Li Xiuyi; Liu Shuzheng

    2001-01-01

    Objective: To study the anti-tumor effect of IFN γ gene-radiotherapy to murine melanoma and its immunologic mechanism. Methods: pcEgr-IFNγ plasmids were injected locally into tumor, and 36 hours later, the tumors were given 20 Gy X-ray irradiation. Tumor growth at different time, IFN γ expression 3 days later and immunologic indexes 15 days later were detected. Results: At 3-15 days after pcEgr-IFNγ gene-radiotherapy, the tumor growth rate was lower than that of irradiation alone group. It was also lower than that of gene therapy alone group and control plasmid combined with X-ray irradiation group significantly. Day 3 tumor IFN γ expression was higher than that of plasmid treatment alone group. NK activity, IL-2 and IFN γ secretion activities were higher than those of gene therapy alone and irradiation alone groups significantly. Conclusion: The antitumor effect of IFN γ gene-radiotherapy is better than that of either of them applied solely. Its mechanism might be concerned with the higher expression of IFN γ induced by irradiation in tumors and activation of anti-tumor immunologic functions

  12. Novel fusion genes and chimeric transcripts in ependymal tumors

    DEFF Research Database (Denmark)

    Olsen, Thale Kristin; Panagopoulos, Ioannis; Gorunova, Ludmila

    2016-01-01

    using the FusionCatcher algorithm on 12 RNA-sequenced ependymal tumors. Candidate transcripts were prioritized based on the software's filtering and manual visualization using the BLAST (Basic Local Alignment Search Tool) and BLAT (BLAST-like alignment tool) tools. Genomic and reverse transcriptase PCR......We have previously identified two ALK rearrangements in a subset of ependymal tumors using a combination of cytogenetic data and RNA sequencing. The aim of this study was to perform an unbiased search for fusion transcripts in our entire series of ependymal tumors. Fusion analysis was performed...... with subsequent Sanger sequencing was used to validate the potential fusions. Fluorescent in situ hybridization (FISH) using locus-specific probes was also performed. A total of 841 candidate chimeric transcripts were identified in the 12 tumors, with an average of 49 unique candidate fusions per tumor. After...

  13. DNA Methylation and Gene Expression Profiling of Ewing Sarcoma Primary Tumors Reveal Genes That Are Potential Targets of Epigenetic Inactivation

    Directory of Open Access Journals (Sweden)

    Nikul Patel

    2012-01-01

    Full Text Available The role of aberrant DNA methylation in Ewing sarcoma is not completely understood. The methylation status of 503 genes in 52 formalin-fixed paraffin-embedded EWS tumors and 3 EWS cell lines was compared to human mesenchymal stem cell primary cultures (hMSCs using bead chip methylation analysis. Relative expression of methylated genes was assessed in 5-Aza-2-deoxycytidine-(5-AZA-treated EWS cell lines and in a cohort of primary EWS samples and hMSCs by gene expression and quantitative RT-PCR. 129 genes demonstrated statistically significant hypermethylation in EWS tumors compared to hMSCs. Thirty-six genes were profoundly methylated in EWS and unmethylated in hMSCs. 5-AZA treatment of EWS cell lines resulted in upregulation of expression of hundreds of genes including 162 that were increased by at least 2-fold. The expression of 19 of 36 candidate hypermethylated genes was increased following 5-AZA. Analysis of gene expression from an independent cohort of tumors confirmed decreased expression of six of nineteen hypermethylated genes (AXL, COL1A1, CYP1B1, LYN, SERPINE1, and VCAN. Comparing gene expression and DNA methylation analyses proved to be an effective way to identify genes epigenetically regulated in EWS. Further investigation is ongoing to elucidate the role of these epigenetic alterations in EWS pathogenesis.

  14. Assessment of tumor characteristic gene expression in cell lines using a tissue similarity index (TSI).

    Science.gov (United States)

    Sandberg, Rickard; Ernberg, Ingemar

    2005-02-08

    The gene expression profiles of 60 cell lines, derived from nine different tissues, were compared with their corresponding in vivo tumors and tissues. Cell lines expressed few tissue-specific (2%) or tumor-specific (5%) genes when analyzed group-wise. A tissue similarity index (TSI) was designed based upon singular value decomposition that measured in vivo tumor characteristic gene expression in each cell line independently. Only 34 of the 60 cell lines received the highest TSI toward its tumor of origin. In addition, we identified the most appropriate cell lines to be used as model systems for different in vivo tumors. Seven cell lines were identified as being of another origin than the originally presumed one. The proposed TSI will likely become an important tool for the selection of the most appropriate cell lines in pharmaceutical screening programs and experimental and biomedical research.

  15. Differential Gene Expression in Primary Breast Tumors Associated with Lymph Node Metastasis

    Directory of Open Access Journals (Sweden)

    Rachel E. Ellsworth

    2011-01-01

    Full Text Available Lymph node status remains one of the most useful prognostic indicators in breast cancer; however, current methods to assess nodal status disrupt the lymphatic system and may lead to secondary complications. Identification of molecular signatures discriminating lymph node-positive from lymph node-negative primary tumors would allow for stratification of patients requiring surgical assesment of lymph nodes. Primary breast tumors from women with negative (=41 and positive (=35 lymph node status matched for possible confounding factors were subjected to laser microdissection and gene expression data generated. Although ANOVA analysis (1.5 revealed 13 differentially expressed genes, hierarchical clustering classified 90% of node-negative but only 66% of node-positive tumors correctly. The inability to derive molecular profiles of metastasis in primary tumors may reflect tumor heterogeneity, paucity of cells within the primary tumor with metastatic potential, influence of the microenvironment, or inherited host susceptibility to metastasis.

  16. Differential Gene Expression in Primary Breast Tumors Associated with Lymph Node Metastasis

    Science.gov (United States)

    Ellsworth, Rachel E.; Field, Lori A.; Love, Brad; Kane, Jennifer L.; Hooke, Jeffrey A.; Shriver, Craig D.

    2011-01-01

    Lymph node status remains one of the most useful prognostic indicators in breast cancer; however, current methods to assess nodal status disrupt the lymphatic system and may lead to secondary complications. Identification of molecular signatures discriminating lymph node-positive from lymph node-negative primary tumors would allow for stratification of patients requiring surgical assesment of lymph nodes. Primary breast tumors from women with negative (n = 41) and positive (n = 35) lymph node status matched for possible confounding factors were subjected to laser microdissection and gene expression data generated. Although ANOVA analysis (P 1.5) revealed 13 differentially expressed genes, hierarchical clustering classified 90% of node-negative but only 66% of node-positive tumors correctly. The inability to derive molecular profiles of metastasis in primary tumors may reflect tumor heterogeneity, paucity of cells within the primary tumor with metastatic potential, influence of the microenvironment, or inherited host susceptibility to metastasis. PMID:22295210

  17. The Function of PTEN Tumor Suppressor Gene in Prostate Cancer Development

    National Research Council Canada - National Science Library

    Wu, Hong

    2001-01-01

    .... The recently identified tumor suppressor gene PTEN is a promising candidate for being involved in prostate cancer since it is frequently deleted in prostate cancer, especially in advanced or metastatic forms...

  18. The Function of PTEN Tumor Suppressor Gene in Prostate Cancer Development

    National Research Council Canada - National Science Library

    Wu, Hong

    2002-01-01

    .... The recently identified tumor suppressor gene PTEN is a promising candidate for being involved in prostate cancer since it is frequently deleted in prostate cancer, especially in advanced or metastatic forms...

  19. Regulation of IAP (Inhibitor of Apoptosis) Gene Expression by the p53 Tumor Suppressor Protein

    National Research Council Canada - National Science Library

    Murphy, Maureen

    2003-01-01

    The goal of the work proposed in this application, which has just completed Year 1, was to analyze the ability of the p53 tumor suppressor protein to repress the anti-apoptotic genes survivin and cIAP-2...

  20. Gene expression profiling of circulating tumor cells and peripheral blood mononuclear cells from breast cancer patients

    Czech Academy of Sciences Publication Activity Database

    Hensler, M.; Vancurova, I.; Becht, E.; Palata, O.; Strnad, P.; Tesarova, P.; Cabinakova, M.; Švec, David; Kubista, Mikael; Bartunkova, J.; Spisek, R.; Sojka, L.

    2016-01-01

    Roč. 5, č. 4 (2016), e1102827 ISSN 2162-402X Institutional support: RVO:86652036 Keywords : Breast cancer * gene expression profiling * circulating tumor cells Subject RIV: FD - Oncology ; Hematology Impact factor: 7.719, year: 2016

  1. RNA quality and gene expression analysis of ovarian tumor tissue undergoing repeated thaw-freezing

    DEFF Research Database (Denmark)

    Jochumsen, Kirsten Marie; Tan, Qihua; Dahlgaard, Jesper

    2007-01-01

    undergoes repeated thawing and freezing. We evaluated the influence of repeated division of tumor samples at room temperature, on RNA quality and quantity, in addition to the gene expression profile. Sixteen ovarian tumor samples were divided in three aliquots each, undergoing respectively one, two...... unsupervised, and supervised multivariate statistical methods, reliability analysis, as well as verification using published gene lists in ovarian cancer studies. RNA quality and quantity did not change during the division procedure and microarray data showed insignificant difference in gene expression. Tumor......Gene expression profiles evaluated by microarray-based quantization of RNA are used in studies of differential diagnosis and prognosis in cancer. RNA of good quality is mandatory for this evaluation. The RNA most often comes from tumor banks with limited amount of tissue, and the tissue often...

  2. Rad51C-ATXN7 fusion gene expression in colorectal tumors.

    Science.gov (United States)

    Kalvala, Arjun; Gao, Li; Aguila, Brittany; Dotts, Kathleen; Rahman, Mohammad; Nana-Sinkam, Serge P; Zhou, Xiaoping; Wang, Qi-En; Amann, Joseph; Otterson, Gregory A; Villalona-Calero, Miguel A; Duan, Wenrui

    2016-06-13

    Fusion proteins have unique oncogenic properties and their identification can be useful either as diagnostic or therapeutic targets. Next generation sequencing data have previously shown a fusion gene formed between Rad51C and ATXN7 genes in the MCF7 breast cancer cell line. However, the existence of this fusion gene in colorectal patient tumor tissues is largely still unknown. We evaluated for the presence of Rad51C-ATXN7 fusion gene in colorectal tumors and cells by RT-PCR, PCR, Topo TA cloning, Real time PCR, immunoprecipitation and immunoblotting techniques. We identified two forms of fusion mRNAs between Rad51C and ATXN7 in the colorectal tumors, including a Variant 1 (fusion transcript between Rad51C exons 1-7 and ATXN7 exons 6-13), and a Variant 2 (between Rad51C exons 1-6 and ATXN7 exons 6-13). In silico analysis showed that the Variant 1 produces a truncated protein, whereas the Variant 2 was predicted to produce a fusion protein with molecular weight of 110 KDa. Immunoprecipitation and Western blot analysis further showed a 110 KDa protein in colorectal tumors. 5-Azacytidine treatment of LS-174 T cells caused a 3.51-fold increase in expression of the fusion gene (Variant 2) as compared to no treatment controls evaluated by real time PCR. In conclusion we found a fusion gene between DNA repair gene Rad51C and neuro-cerebral ataxia Ataxin-7 gene in colorectal tumors. The in-frame fusion transcript of Variant 2 results in a fusion protein with molecular weight of 110 KDa. In addition, we found that expression of fusion gene is associated with functional impairment of Fanconi Anemia (FA) DNA repair pathway in colorectal tumors. The expression of Rad51C-ATXN7 in tumors warrants further investigation, as it suggests the potential of the fusion gene in treatment and predictive value in colorectal cancers.

  3. Hypoxia-Inducible Regulation of a Prodrug-Activating Enzyme for Tumor-Specific Gene Therapy

    Directory of Open Access Journals (Sweden)

    Toru Shibata

    2002-01-01

    Full Text Available Previous studies have suggested that tumor hypoxia could be exploited for cancer gene therapy. Using hypoxia-responsive elements derived from the human vascular endothelial growth factor gene, we have generated vectors expressing a bacterial nitroreductase. (20NTR gene that can activate the anticancer prodrug CB1954. Stable transfectants of human HT1080 tumor cells with hypoxia-inducible vectors were established with G418 selection. Hypoxic induction of NTR protein correlated with increased sensitivity to in vitro exposure of HT 1080 cells to the prodrug. Growth delay assays were performed with established tumor xenografts derived from the same cells to detect the in vivo efficacy of CB1954 conversion to its cytotoxic form. Significant antitumor effects were achieved with intraperitoneal injections of CB1954 both in tumors that express NTR constitutively or with a hypoxia-inducible promoter. In addition, respiration of 10% O2 increased tumor hypoxia in vivo and enhanced the antitumor effects. Taken together, these results demonstrate that hypoxia-inducible vectors may be useful for tumor-selective gene therapy, although the problem of delivery of the vector to the tumors, particularly to the hypoxic cells in the tumors, is not addressed by these studies.

  4. Restriction landmark genomic scanning of mouse liver tumors for gene amplification: overexpression of cyclin A2.

    Science.gov (United States)

    Haddad, R; Morrow, A D; Plass, C; Held, W A

    2000-07-21

    SV40 T/t antigen-induced liver tumors from transgenic mice were analyzed by Restriction Landmark Genomic Scanning (RLGS). Using NotI as the restriction landmark, RLGS targets CpG islands found in gene-rich regions of the genome. Since many RLGS landmarks are mapped, the candidate gene approach can be used to help determine which genes are altered in tumors. RLGS analysis revealed one tumor-specific amplification mapping close to CcnA2 (cyclin A2) and Fgf2 (fibroblast growth factor 2). Southern analysis confirmed that both oncogenes are amplified in this tumor and in a second, independent liver tumor. Whereas Fgf2 RNA is undetectable in tumors, CcnA2 RNA and cyclin A2 protein was overexpressed in 25 and 50% of tumors, respectively. Combining RLGS with the candidate gene approach indicates that cyclin A2 amplification and overexpression is a likely selected event in transgenic mouse liver tumors. Our results also indicate that our mouse model for liver tumorigenesis in mice accurately recapitulates events observed in human hepatocellular carcinoma. Copyright 2000 Academic Press.

  5. Regional and temporal differences in gene expression of LH(BETA)T(AG) retinoblastoma tumors.

    Science.gov (United States)

    Houston, Samuel K; Pina, Yolanda; Clarke, Jennifer; Koru-Sengul, Tulay; Scott, William K; Nathanson, Lubov; Schefler, Amy C; Murray, Timothy G

    2011-07-23

    The purpose of this study was to evaluate by microarray the hypothesis that LH(BETA)T(AG) retinoblastoma tumors exhibit regional and temporal variations in gene expression. LH(BETA)T(AG) mice aged 12, 16, and 20 weeks were euthanatized (n = 9). Specimens were taken from five tumor areas (apex, anterior lateral, center, base, and posterior lateral). Samples were hybridized to gene microarrays. The data were preprocessed and analyzed, and genes with a P 2.5 were considered to be differentially expressed. Differentially expressed genes were analyzed for overlap with known networks by using pathway analysis tools. There were significant temporal (P 2.5, there were significant changes in gene expression of 190 genes apically, 84 genes anterolaterally, 126 genes posteriorly, 56 genes centrally, and 134 genes at the base. Differentially expressed genes overlapped with known networks, with significant involvement in regulation of cellular proliferation and growth, response to oxygen levels and hypoxia, regulation of cellular processes, cellular signaling cascades, and angiogenesis. There are significant temporal and regional variations in the LH(BETA)T(AG) retinoblastoma model. Differentially expressed genes overlap with key pathways that may play pivotal roles in murine retinoblastoma development. These findings suggest the mechanisms involved in tumor growth and progression in murine retinoblastoma tumors and identify pathways for analysis at a functional level, to determine significance in human retinoblastoma. Microarray analysis of LH(BETA)T(AG) retinal tumors showed significant regional and temporal variations in gene expression, including dysregulation of genes involved in hypoxic responses and angiogenesis.

  6. Dissecting Time- from Tumor-Related Gene Expression Variability in Bilateral Breast Cancer

    Directory of Open Access Journals (Sweden)

    Maurizio Callari

    2018-01-01

    Full Text Available Metachronous (MBC and synchronous bilateral breast tumors (SBC are mostly distinct primaries, whereas paired primaries and their local recurrences (LRC share a common origin. Intra-pair gene expression variability in MBC, SBC, and LRC derives from time/tumor microenvironment-related and tumor genetic background-related factors and pairs represents an ideal model for trying to dissect tumor-related from microenvironment-related variability. Pairs of tumors derived from women with SBC (n = 18, MBC (n = 11, and LRC (n = 10 undergoing local-regional treatment were profiled for gene expression; similarity between pairs was measured using an intraclass correlation coefficient (ICC computed for each gene and compared using analysis of variance (ANOVA. When considering biologically unselected genes, the highest correlations were found for primaries and paired LRC, and the lowest for MBC pairs. By instead limiting the analysis to the breast cancer intrinsic genes, correlations between primaries and paired LRC were enhanced, while lower similarities were observed for SBC and MBC. Focusing on stromal-related genes, the ICC values decreased for MBC and were significantly different from SBC. These findings indicate that it is possible to dissect intra-pair gene expression variability into components that are associated with genetic origin or with time and microenvironment by using specific gene subsets.

  7. Copy Number Alterations in Enzyme-Coding and Cancer-Causing Genes Reprogram Tumor Metabolism.

    Science.gov (United States)

    Sharma, Ashwini Kumar; Eils, Roland; König, Rainer

    2016-07-15

    Somatic copy number alterations frequently occur in the cancer genome affecting not only oncogenic or tumor suppressive genes, but also passenger and potential codriver genes. An intrinsic feature resulting from such genomic perturbations is the deregulation in the metabolism of tumor cells. In this study, we have shown that metabolic and cancer-causing genes are unexpectedly often proximally positioned in the chromosome and share loci with coaltered copy numbers across multiple cancers (19 cancer types from The Cancer Genome Atlas). We have developed an analysis pipeline, Identification of Metabolic Cancer Genes (iMetCG), to infer the functional impact on metabolic remodeling from such coamplifications and codeletions and delineate genes driving cancer metabolism from those that are neutral. Using our identified metabolic genes, we were able to classify tumors based on their tissue and developmental origins. These metabolic genes were similar to known cancer genes in terms of their network connectivity, isoform frequency, and evolutionary features. We further validated these identified metabolic genes by (i) using gene essentiality data from several tumor cell lines, (ii) showing that these identified metabolic genes are strong indicators for patient survival, and (iii) observing a significant overlap between our identified metabolic genes and known cancer-metabolic genes. Our analyses revealed a hitherto unknown generic mechanism for large-scale metabolic reprogramming in cancer cells based on linear gene proximities between cancer-causing and -metabolic genes. We have identified 119 new metabolic cancer genes likely to be involved in rewiring cancer cell metabolism. Cancer Res; 76(14); 4058-67. ©2016 AACR. ©2016 American Association for Cancer Research.

  8. Assessment of Tumor Heterogeneity, as Evidenced by Gene Expression Profiles, Pathway Activation, and Gene Copy Number, in Patients with Multifocal Invasive Lobular Breast Tumors

    Science.gov (United States)

    Norton, Nadine; Advani, Pooja P.; Serie, Daniel J.; Geiger, Xochiquetzal J.; Necela, Brian M.; Axenfeld, Bianca C.; Kachergus, Jennifer M.; Feathers, Ryan W.; Carr, Jennifer M.; Crook, Julia E.; Moreno-Aspitia, Alvaro; Anastasiadis, Panos Z.; Perez, Edith A.; Thompson, E. Aubrey

    2016-01-01

    Background Invasive lobular carcinoma (ILC) comprises approximately ~10–20% of breast cancers. In general, multifocal/multicentric (MF/MC) breast cancer has been associated with an increased rate of regional lymph node metastases. Tumor heterogeneity between foci represents a largely unstudied source of genomic variation in those rare patients with MF/MC ILC. Methods We characterized gene expression and copy number in 2 or more foci from 11 patients with MF/MC ILC (all ER+, HER2-) and adjacent normal tissue. RNA and DNA were extracted from 3x1.5mm cores from all foci. Gene expression (730 genes) and copy number (80 genes) were measured using Nanostring PanCancer and Cancer CNV panels. Linear mixed models were employed to compare expression in tumor versus normal samples from the same patient, and to assess heterogeneity (variability) in expression among multiple ILC within an individual. Results 35 and 34 genes were upregulated (FC>2) and down-regulated (FC<0.5) respectively in ILC tumor relative to adjacent normal tissue, q<0.05. 9/34 down-regulated genes (FIGF, RELN, PROM1, SFRP1, MMP7, NTRK2, LAMB3, SPRY2, KIT) had changes larger than CDH1, a hallmark of ILC. Copy number changes in these patients were relatively few but consistent across foci within each patient. Amplification of three genes (CCND1, FADD, ORAOV1) at 11q13.3 was present in 2/11 patients in both foci. We observed significant evidence of within-patient between-foci variability (heterogeneity) in gene expression for 466 genes (p<0.05 with FDR 8%), including CDH1, FIGF, RELN, SFRP1, MMP7, NTRK2, LAMB3, SPRY2 and KIT. Conclusions There was substantial variation in gene expression between ILC foci within patients, including known markers of ILC, suggesting an additional level of complexity that should be addressed. PMID:27078887

  9. Modulation and Expression of Tumor Suppressor Genes by Environmental Agents

    National Research Council Canada - National Science Library

    Ostrander, Gary Kent

    1996-01-01

    ... in the retinoblastoma gene in retinoblastoma and hepatocarcinomas following induction with known environmental carcinogens. Studies to date suggest the retinoblastoma gene/protein may play a role in oncogenesis in the medaka.

  10. PCR Expression Analysis Of the Estrogeninducible Gene Bcei in Gastrointestinal and Other Human Tumors

    Directory of Open Access Journals (Sweden)

    Iris Wundrack

    1994-01-01

    Full Text Available A polymerase chain reaction (PCR assay was developed to test for tumor cell specific expression of the BCEI gene. This new marker gene, reported at first for human breast cancer, was found specifically active in various gastrointestinal carcinomas by previously applying immunohistochemistry and RNA (Northern blot analysis. Presently, by using reverse transcription -PCR analysis, a series of primary tumor tissues and established tumor cell lines were testcd for BCEI transcription. This approach was compared to immunostaining achieved by an antibody directed against the BCEI gene’s product. The result demonstrate the superior sensitivity of PCR by indicating the gene’ s expression in cases where immunohistochemical testing remained negative.

  11. Gene expression profiling of MYC-driven tumor signatures in porcine liver stem cells by transcriptome sequencing

    Science.gov (United States)

    It is now well-established that cancer stem cells (CSCs) drive tumor growth and that the cancer gene, c-Myc, plays a critical role in converting cells to CSCs. However, little is known about the genes that are induced and regulated by c-Myc to generate tumors, and, in particular, tumors of the live...

  12. Alterations in the K-ras and p53 genes in rat lung tumors

    Energy Technology Data Exchange (ETDEWEB)

    Belinsky, S.A.; Swafford, D.S.; Finch, G.L.; Mitchell, C.E. [Inhalation Toxicology Research Institute, Albuquerque, NM (United States)] [and others

    1997-06-01

    Activation of the K-ras protooncogene and inactivation of the p53 tumor suppressor gene are events common to many types of human cancers. Molecular epidemiology studies have associated mutational profiles in these genes with specific exposures. The purpose of this paper is to review investigations that have examined the role of the K-ras and p53 genes in lung tumors induced in the F344 rat by mutagenic and nonmutagenic exposures. Mutation profiles within the K-ras and p53 genes, if present in rat lung tumors, would help to define some of the molecular mechanisms underlying cancer induction by various environmental agents. Pulmonary adenocarcinomas or squamous cell carcinomas were induced by tetranitromethane (TNM), 4-methylnitrosamino-1-(3-pyridyl)-1-butanone (NNK), beryllium metal, plutonium-239, X-ray, diesel exhaust, or carbon black. These agents were chosen because the tumors they produced could arise via different types of DNA damage. Mutation of the K-ras gene was determined by approaches that included DNA transfection, direct sequencing, mismatch hybridization, and restriction fragment length polymorphism analysis. The frequency for mutation of the K-ras gene was exposure dependent. The transition mutations formed could have been derived from deamination of cytosine. Alteration in the p53 gene was assessed by immunohistochemical analysis for p53 protein and single-strand conformation polymorphism (SSCP) analysis of exons 4 to 9. None of the 93 adenocarinomas examined was immunoreactive toward the anti-p53 antibody CM1. In contrast, 14 of 71 squamous cell carcinomas exhibited nuclear p53 immunoreactivity with no correlation to type of exposure. However, SSCP analysis only detected mutations in 2 of 14 squamous cell tumors that were immunoreactive, suggesting that protein stabilization did not stem from mutations within the p53 gene. Thus, the p53 gene does not appear to be involved in the genesis of most rat lung tumors. 2 figs., 2 tabs., 48 refs.

  13. Fanconi Anemia Gene Mutations Are Not Involved in Sporadic Wilms Tumor

    NARCIS (Netherlands)

    Adank, Muriel A.; Segers, Heidi; van Mil, Saskia E.; van Helsdingen, Yvette M.; Ameziane, Najim; van den Ouweland, Ans M. W.; Wagner, Anja; Meijers-Heijboer, Hanne; Kool, Marcel; de Kraker, Jan; Waisfisz, Quinten; van den Heuvel-Eibrink, Marry M.

    2010-01-01

    Bi-allelic germline mutations of the Fancom anemia (FA) genes, PALB2/FANCN and BRCA2/FANCD1, have been reported in a few Wilms tumor (WT) patients with an atypical FA phenotype Therefore, we screened a random cohort of 47 Dutch WT cases for germline mutations in these two FA-genes by DNA sequencing

  14. Hypoxia Inducible Factor-independent functions for the von Hippel-Lindau tumor suppressor gene

    NARCIS (Netherlands)

    Lolkema, Martijn Paul Jung Kyu

    2006-01-01

    Inactivating mutations of the von Hippel-Lindau gene (VHL) on chromosome 3p have been associated with the autosomal dominant VHL disease, characterized by extensively vascularized tumors and cysts in different organs, as well as the majority of conventional kidney cancers. The VHL gene product

  15. Locally linear representation Fisher criterion based tumor gene expressive data classification.

    Science.gov (United States)

    Li, Bo; Tian, Bei-Bei; Zhang, Xiao-Long; Zhang, Xiao-Ping

    2014-10-01

    Tumor gene expressive data are characterized by a large amount of genes with only a small amount of observations, which always appear with high dimensionality. So it is necessary to reduce the dimensionality before identifying their genre. In this paper, a discriminant manifold learning method, named locally linear representation Fisher criterion (LLRFC), is applied to extract features from tumor gene expressive data. In LLRFC, an inter-class graph and an intra-class graph are constructed based on their genre information, where any tumor gene expressive data in the inter-class graph should select k nearest neighbors with different class labels and in the intra-class graph the k nearest neighbors for any tumor gene expressive data must be sampled from those with the same class. And then the locally least linear reconstruction is introduced to optimize the corresponding weights in both graphs. Moreover, a Fisher criterion is modeled to explore a low dimensional subspace where the reconstruction errors in the inter-class graph can be maximized and the reconstruction errors in the intra-class graph can be minimized, simultaneously. Experiments on some benchmark tumor gene expressive data have been conducted with some related algorithms, by which the proposed LLRFC has been validated to be efficient. Copyright © 2014 Elsevier Ltd. All rights reserved.

  16. Gene Promoter Hypermethylation in Tumors and Plasma of Breast Cancer Patients

    Science.gov (United States)

    Shim, Young Ran; Choi, Joon Hyuk; Kim, Mi Jin; Gabrielson, Edward; Lee, Soo Jung; Hwang, Tae Yoon; Shin, Sei One

    2005-01-01

    Purpose To measure the hypermethylation of four genes in primary tumors and paired plasma samples to determine the feasibility of gene promoter hypermethylation markers for detecting breast cancer in the plasma. Materials and Methods DNA was extracted from the tumor tissues and peripheral blood plasma of 34 patients with invasive breast cancer, and the samples examined for aberrant hypermethylation in cyclin D2, retinoic acid receptor β (RARβ), twist and high in normal-1 (HIN-1) genes using methylation-specific PCR (MSP), and the results correlated with the clinicopathological parameters. Results Promoter hypermethylation was detected at high frequency in the primary tumors for cyclin D2 (53%), RARβ (56%), twist (41%) and HIN-1 (77%). Thirty-three of the 34 (97%) primary tumors displayed promoter hypermethylation in at least one of the genes examined. The corresponding plasma samples showed hyperme thylation of the same genes, although at lower frequencies (6% for cyclin D2, 16% for RARβ, 36% for twist, and 54% for HIN-1). Overall, 22 of the 33 (67%) primary tumors with hypermethylation of at least one of the four genes also had abnormally hypermethylated DNA in their matched plasma samples. No significant relationship was recognized between any of the clinical or pathological parameters (tumor size, axillary lymph node metastasis, stage, or Ki-67 labeling index) with the frequency of hypermethylated DNA in the primary tumor or plasma. Conclusion The detection of aberrant promoter hypermethylation of cancer-related genes in the plasma may be a useful tool for the detection of breast cancer. PMID:19956520

  17. Tumor suppressor genes that escape from X-inactivation contribute to cancer sex bias

    OpenAIRE

    Dunford, Andrew; Weinstock, David M.; Savova, Virginia; Schumacher, Steven E.; Cleary, John P.; Yoda, Akinori; Sullivan, Timothy J.; Hess, Julian M.; Gimelbrant, Alexander A.; Beroukhim, Rameen; Lawrence, Michael S.; Getz, Gad; Lane, Andrew A.

    2016-01-01

    There is a striking and unexplained male predominance across many cancer types. A subset of X chromosome (chrX) genes can escape X-inactivation, which would protect females from complete functional loss by a single mutation. To identify putative “Escape from X-Inactivation Tumor Suppressor” (EXITS) genes, we compared somatic alterations from >4100 cancers across 21 tumor types for sex bias. Six of 783 non-pseudoautosomal region (PAR) chrX genes (ATRX, CNKSR2, DDX3X, KDM5C, KDM6A, and MAGEC3) ...

  18. Radiation immunomodulatory gene tumor therapy of rats with intracerebral glioma tumors

    DEFF Research Database (Denmark)

    Persson, Bertil R R; Koch, Catrin Bauréus; Grafström, Gustav

    2010-01-01

    Single-fraction radiation therapy with 5 or 15 Gy (60)Co gamma radiation was combined with intraperitoneal injections of syngeneic interferon gamma (IFN-gamma)-transfected cells in rats with intracerebral N29 or N32 glioma tumors at days 7, 21 and 35 after inoculation. For intracerebral N29 tumors......, single-fraction radiation therapy with 5 or 15 Gy had no significant effect on the survival time. Immunization with IFN-gamma-transfected N29 cells significantly increased the survival time by 61%. Single-fraction radiation therapy with 5 Gy combined with immunization increased the survival time...... significantly by 87% and complete remissions by 75% while with 15 Gy the survival time increased 45% with 38% complete remissions. For intracerebral N32 tumors, single-fraction radiation therapy with 15 Gy increased the survival time significantly by 20%. Immunization by itself had no significant effect...

  19. Lapachol as an epithelial tumor inhibitor agent in Drosophila melanogaster heterozygote for tumor suppressor gene wts.

    Science.gov (United States)

    Costa, W F; Oliveira, A B; Nepomuceno, J C

    2011-12-22

    The search for new and effective antitumor agents with fewer cytotoxic side effects on normal tissue has increasingly become important. Lapachol, a natural organic compound isolated from the lapacho tree (Tabebuia avellandedae), is chemically identified as belonging to the naphthoquinone group and is known for its anti-inflammatory, analgesic and antibiotic properties, although there are questions about its effectiveness for treating neoplasic cells. We evaluated the antitumoral effects of lapachol by testing for clones of epithelial tumors in Drosophila melanogaster. Seventy-two-hour old larvae bred from wts/TM3, Sb(1) females and mwh/mwh males, were treated with different concentrations of lapachol (20, 40 and 60 μg/mL). Lapachol alone did not significantly increase the number of epithelial tumors. However, lapachol did significantly reduce the number of tumors provoked by doxorubicin.

  20. A mutation screening of oncogenes, tumor suppressor gene TP53 and nuclear encoded mitochondrial complex I genes in oncocytic thyroid tumors.

    Science.gov (United States)

    Evangelisti, Cecilia; de Biase, Dario; Kurelac, Ivana; Ceccarelli, Claudio; Prokisch, Holger; Meitinger, Thomas; Caria, Paola; Vanni, Roberta; Romeo, Giovanni; Tallini, Giovanni; Gasparre, Giuseppe; Bonora, Elena

    2015-03-21

    Thyroid neoplasias with oncocytic features represent a specific phenotype in non-medullary thyroid cancer, reflecting the unique biological phenomenon of mitochondrial hyperplasia in the cytoplasm. Oncocytic thyroid cells are characterized by a prominent eosinophilia (or oxyphilia) caused by mitochondrial abundance. Although disruptive mutations in the mitochondrial DNA (mtDNA) are the most significant hallmark of such tumors, oncocytomas may be envisioned as heterogeneous neoplasms, characterized by multiple nuclear and mitochondrial gene lesions. We investigated the nuclear mutational profile of oncocytic tumors to pinpoint the mutations that may trigger the early oncogenic hit. Total DNA was extracted from paraffin-embedded tissues from 45 biopsies of oncocytic tumors. High-resolution melting was used for mutation screening of mitochondrial complex I subunits genes. Specific nuclear rearrangements were investigated by RT-PCR (RET/PTC) or on isolated nuclei by interphase FISH (PAX8/PPARγ). Recurrent point mutations were analyzed by direct sequencing. In our oncocytic tumor samples, we identified rare TP53 mutations. The series of analyzed cases did not include poorly- or undifferentiated thyroid carcinomas, and none of the TP53 mutated cases had significant mitotic activity or high-grade features. Thus, the presence of disruptive TP53 mutations was completely unexpected. In addition, novel mutations in nuclear-encoded complex I genes were identified. These findings suggest that nuclear genetic lesions altering the bioenergetics competence of thyroid cells may give rise to an aberrant mitochondria-centered compensatory mechanism and ultimately to the oncocytic phenotype.

  1. Wilms tumor gene 1 (WT1) is a prognostic marker in high-grade uterine sarcoma.

    Science.gov (United States)

    Coosemans, An; Van Calster, Ben; Verbist, Godelieve; Moerman, Philippe; Vergote, Ignace; Van Gool, Stefaan W; Amant, Frédéric

    2011-02-01

    Wilms tumor gene 1 (WT1) contributes to uterine sarcoma tumor biology. In this study, we aimed to clarify the prognostic value of WT1. A retrospective clinical and histopathological review of 71 women with high-grade uterine sarcoma (leiomyosarcoma [n = 24], undifferentiated sarcoma [n = 9]), and carcinosarcoma (n = 38) was performed. Patients were followed up for at least 12 months. Wilms tumor gene 1 expression was determined by immunohistochemistry. Data on recurrence (progression-free survival) and overall survival (OS) were available for all patients. Univariate and multivariate analyses of WT1 expression were carried out using Kaplan-Meier curves and Cox regression, respectively. Forty-nine (69%) tumors were WT1 positive. Forty-seven (66%) patients died of the disease, with a median OS time of 22 months. Wilms tumor gene 1 was a predictor of survival in the univariate analysis: the hazard ratio of WT1 positivity was 2.44 (95% confidence interval, 1.34-4.71) for progression-free survival and 2.48 (95% confidence interval, 1.26-4.90) for OS. Multivariate analysis including stage, age, tumor size, and sarcoma subtype identified only stage and WT1 positivity as independent prognostic markers for survival. The identification of WT1 as a prognostic marker confirms its role in high-grade uterine sarcoma and carcinosarcoma tumor biology.

  2. TFPI-2 is a putative tumor suppressor gene frequently inactivated by promoter hypermethylation in nasopharyngeal carcinoma

    International Nuclear Information System (INIS)

    Wang, Shumin; Ma, Ning; Murata, Mariko; Huang, Guangwu; Zhang, Zhe; Xiao, Xue; Zhou, Xiaoying; Huang, Tingting; Du, Chunping; Yu, Nana; Mo, Yingxi; Lin, Longde; Zhang, Jinyan

    2010-01-01

    Epigenetic silencing of tumor suppressor genes play important roles in NPC tumorgenesis. Tissue factor pathway inhibitor-2 (TFPI-2), is a protease inhibitor. Recently, TFPI-2 was suggested to be a tumor suppressor gene involved in tumorigenesis and metastasis in some cancers. In this study, we investigated whether TFPI-2 was inactivated epigenetically in nasopharyngeal carcinoma (NPC). Transcriptional expression levels of TFPI-2 was evaluated by RT-PCR. Methylation status were investigated by methylation specific PCR and bisulfate genomic sequencing. The role of TFPI-2 as a tumor suppressor gene in NPC was addressed by re-introducing TFPI-2 expression into the NPC cell line CNE2. TFPI-2 mRNA transcription was inactivated in NPC cell lines. TFPI-2 was aberrantly methylated in 66.7% (4/6) NPC cell lines and 88.6% (62/70) of NPC primary tumors, but not in normal nasopharyngeal epithelia. TFPI-2 expression could be restored in NPC cells after demethylation treatment. Ectopic expression of TFPI-2 in NPC cells induced apoptosis and inhibited cell proliferation, colony formation and cell migration. Epigenetic inactivation of TFPI-2 by promoter hypermethylation is a frequent and tumor specific event in NPC. TFPI-2 might be considering as a putative tumor suppressor gene in NPC

  3. Haploinsufficiency of the genes encoding the tumor suppressor Pten predisposes zebrafish to hemangiosarcoma

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    Suma Choorapoikayil

    2012-03-01

    PTEN is an essential tumor suppressor that antagonizes Akt/PKB signaling. The zebrafish genome encodes two Pten genes, ptena and ptenb. Here, we report that zebrafish mutants that retain a single wild-type copy of ptena or ptenb (ptena+/−ptenb−/− or ptena−/−ptenb+/− are viable and fertile. ptena+/−ptenb−/− fish develop tumors at a relatively high incidence (10.2% and most tumors developed close to the eye (26/30. Histopathologically, the tumor masses were associated with the retrobulbar vascular network and diagnosed as hemangiosarcomas. A single tumor was identified in 42 ptena−/−ptenb+/− fish and was also diagnosed as hemangiosarcoma. Immunohistochemistry indicated that the tumor cells in ptena+/−ptenb−/− and ptena−/−ptenb+/− fish proliferated rapidly and were of endothelial origin. Akt/PKB signaling was activated in the tumors, whereas Ptena was still detected in tumor tissue from ptena+/−ptenb−/− zebrafish. We conclude that haploinsufficiency of the genes encoding Pten predisposes to hemangiosarcoma in zebrafish.

  4. Haploinsufficiency of the genes encoding the tumor suppressor Pten predisposes zebrafish to hemangiosarcoma.

    Science.gov (United States)

    Choorapoikayil, Suma; Kuiper, Raoul V; de Bruin, Alain; den Hertog, Jeroen

    2012-03-01

    PTEN is an essential tumor suppressor that antagonizes Akt/PKB signaling. The zebrafish genome encodes two Pten genes, ptena and ptenb. Here, we report that zebrafish mutants that retain a single wild-type copy of ptena or ptenb (ptena(+/-)ptenb(-/-) or ptena(-/-)ptenb(+/-)) are viable and fertile. ptena(+/-)ptenb(-/-) fish develop tumors at a relatively high incidence (10.2%) and most tumors developed close to the eye (26/30). Histopathologically, the tumor masses were associated with the retrobulbar vascular network and diagnosed as hemangiosarcomas. A single tumor was identified in 42 ptena(-/-)ptenb(+/-) fish and was also diagnosed as hemangiosarcoma. Immunohistochemistry indicated that the tumor cells in ptena(+/-)ptenb(-/-) and ptena(-/-)ptenb(+/-) fish proliferated rapidly and were of endothelial origin. Akt/PKB signaling was activated in the tumors, whereas Ptena was still detected in tumor tissue from ptena(+/-)ptenb(-/-) zebrafish. We conclude that haploinsufficiency of the genes encoding Pten predisposes to hemangiosarcoma in zebrafish.

  5. Modulation and Expression of Tumor Suppressor Genes by Environmental Agents.

    Science.gov (United States)

    1996-12-01

    Den Otter 1990). In a preliminary report (Windle et al. 1990), a transgenic mouse that develops intraocular neoplasms similar to human retinoblastoma...et al. 1974; McFall et al. 1978; Bogenmann and Mark 1983), and a very recent report of heritable ocular tumors in transgenic mice (Windle et al. 1990...additional pair of forceps (fine Halstead Mosquito hemostatic curved forceps 12.7 cm) were used to clamp off the retracted liver transversely just anterior to

  6. Prolactin gene expression in primary central nervous system tumors

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    Mendes Graziella Alebrant

    2013-01-01

    Full Text Available Abstract Background Prolactin (PRL is a hormone synthesized in both the pituitary gland and extrapituitary sites. It has been associated with the occurrence of neoplasms and, more recently, with central nervous system (CNS neoplasms. The aim of this study was to evaluate prolactin expression in primary central nervous system tumors through quantitative real-time PCR and immunohistochemistry (IH. Results Patient mean age was 49.1 years (SD 15.43, and females accounted for 70% of the sample. The most frequent subtype of histological tumor was meningioma (61.5%, followed by glioblastoma (22.9%. Twenty cases (28.6% showed prolactin expression by immunohistochemistry, most of them females (18 cases, 90%. Quantitative real-time PCR did not show any prolactin expression. Conclusions Despite the presence of prolactin expression by IH, the lack of its expression by quantitative real-time PCR indicates that its presence in primary tumors in CNS is not a reflex of local production.

  7. Oncogenic driver genes and the inflammatory microenvironment dictate liver tumor phenotype.

    Science.gov (United States)

    Matter, Matthias S; Marquardt, Jens U; Andersen, Jesper B; Quintavalle, Cristina; Korokhov, Nikolay; Stauffer, Jim K; Kaji, Kosuke; Decaens, Thomas; Quagliata, Luca; Elloumi, Fathi; Hoang, Tanya; Molinolo, Alfredo; Conner, Elizabeth A; Weber, Achim; Heikenwalder, Mathias; Factor, Valentina M; Thorgeirsson, Snorri S

    2016-06-01

    The majority of hepatocellular carcinoma develops in the background of chronic liver inflammation caused by viral hepatitis and alcoholic or nonalcoholic steatohepatitis. However, the impact of different types of chronic inflammatory microenvironments on the phenotypes of tumors generated 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. Also, the impact of DDC-induced chronic liver inflammation was compared between two liver tumor models using a combination of AKT-CAT or AKT-NRAS(G12V) . Treatment with DDC and carbon tetrachloride significantly facilitated the adenoma-to-carcinoma conversion and accelerated the growth of AKT-CAT tumors. Furthermore, DDC treatment altered the morphology of AKT-CAT tumors and caused loss of lipid droplets. Transcriptome analysis of AKT-CAT tumors revealed that cellular growth and proliferation were mainly affected by chronic inflammation and caused up-regulation of Cxcl16, Galectin-3, and Nedd9, among others. Integration with transcriptome profiles from human hepatocellular carcinomas 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 already existent tumor characteristics as supported by transcriptome analysis. However, it also reduced lipid droplets in AKT-NRAS(G12V) tumors. Our study suggests that liver tumor phenotype is defined by a combination of driving oncogenes but also the nature of chronic liver inflammation. (Hepatology 2016;63:1888-1899). © 2016 by the American Association for the Study of Liver Diseases. This article has been contributed to by U.S. Government

  8. Mutational analysis of the extracellular Ca{sup 2+}-sensing receptor gene in human parathyroid tumors

    Energy Technology Data Exchange (ETDEWEB)

    Hosokawa, Yoshitaka; Arnold, A. [Massachusetts General Hospital and Harvard Medical School, Boston, MA (United States); Pollak, M.R.; Brown, E.M. [Brigham and Women`s Hospital, Boston, MA (United States)

    1995-10-01

    Despite recent progress, such as the identification of PRAD1/cyclin D1 as a parathyroid oncogene, it is likely that many genes involved in the molecular pathogenesis of parathyroid tumors remain unknown. Individuals heterozygous for inherited mutations in the extracellular Ca{sup 2+}-sensing receptor gene that reduce its biological activity exhibit a disorder termed familial hypocalciuric hypercalcemia or familial benign hypercalcemia, which is characterized by reduced responsiveness of parathyroid and kidney to calcium and by PTH-dependent hypercalcemia. Those who are homozygous for such mutations present with neonatal severe hyperparathyroidism and have marked parathroid hypercellularity. Thus, the Ca{sup 2+}-sensing receptor gene is a candidate parathyroid tumor suppressor gene, with inactivating mutations plausibly explaining set-point abnormalities in the regulation of both parathyroid cellular proliferation and PTH secretion by extracellular Ca{sup 2+} similar to those seen in hyperparathyroidism. Using a ribonuclease A protection assay that has detected multiple mutations in the Ca{sup 2+}-sensing receptor gene in familial hypocalciuric hypercalcemia and covers more than 90% of its coding region, we sought somatic mutations in this gene in a total of 44 human parathyroid tumors (23 adenomas, 4 carcinomas, 5 primary hyperplasias, and 12 secondary hyperplasias). No such mutations were detected in these 44 tumors. Thus, our studies suggest that somatic mutation of the Ca{sup 2+}-sensing receptor gene does not commonly contribute to the pathogenesis of sporadic parathyroid tumors. As such, PTH set-point dysfunction in parathroid tumors may well be secondary to other clonal proliferative defects and/or mutations in other components of the extracellular Ca{sup 2+}-sensing pathway. 29 refs., 2 figs.

  9. Gene expression and hormone autonomy in radiation-induced tumors of Arabidopsis thaliana

    International Nuclear Information System (INIS)

    Persinger, S.M.; Town, C.D.

    1989-01-01

    In order to study the molecular genetics of factor controlling plant cell growth, we have isolated a group of radiation-induced tumors from Arabidopsis thaliana. Tumors appeared on plants derived from 60 Co gamma-irradiated seed or seedlings, and are capable of hormone-autonomous growth in culture. We have used vertebrate oncogene probes to explore the hypothesis that the tumors arose by the radiation-induced activation of growth-regulating plant oncogenes. One probe, int-2, was used to isolate cDNA clones representing an mRNA differentially expressed between tumors and hormone-dependent callus tissue. The genomic organization and function of this and other differentially expressed Arabidopsis sequences are being further characterized. A second area of study concerns the hormonal status of individual tumors. Tumor tissue varies in color, texture, and degree of differentiation: while some tumors appear undifferentiated, one consistently produces roots, and others occasionally develop shoots or leaflets. The tumors have characteristic growth rates on hormone-free medium, and growth in response to exogenous hormones differs among the tumors themselves and from wild-type. Characterization of the relationships between hormonal status, morphogenesis, and gene expression should yield valuable insights into the mechanisms regulating plant growth and development

  10. [Sebaceous gland tumor with a rare gene mutation within a tumor syndrome: Muir-Torre syndrome].

    Science.gov (United States)

    Voigt, E; Sommer, F; Geiger, K D; Pillunat, L E

    2014-04-01

    Muir-Torre syndrome is a rare autosomal dominant subtype of hereditary nonpolyposis colorectal carcinoma and is characterized by the simultaneous occurrence of sebaceous gland neoplasms with visceral and urogenital malignancies. This article describes the case of a 72-year-old patient who was referred to our clinic for removal of an upper eyelid tumor, showing the course from the clinical findings to the rare diagnosis of Muir-Torre syndrome.

  11. Prediction of DNA methylation in the promoter of gene suppressor tumor.

    Science.gov (United States)

    Saif, Imane; Kasmi, Yassine; Allali, Karam; Ennaji, Moulay Mustapha

    2018-04-20

    The epigenetics methylation of cytosine is the most common epigenetic form in DNA sequences. It is highly concentrated in the promoter regions of the genes, leading to an inactivation of tumor suppressors regardless of their initial function. In this work, we aim to identify the highly methylated regions; the cytosine-phosphate-guanine (CpG) island located on the promoters and/or the first exon gene known for their key roles in the cell cycle, hence the need to study gene-gene interactions. The Frommer and hidden Markov model algorithms are used as computational methods to identify CpG islands with specificity and sensitivity up to 76% and 80%, respectively. The results obtained show, on the one hand, that the genes studied are suspected of developing hypermethylation in the promoter region of the gene involved in the case of a cancer. We then showed that the relative richness in CG results from a high level of methylation. On the other hand, we observe that the gene-gene interaction exhibits co-expression between the chosen genes. This let us to conclude that the hidden Markov model algorithm predicts more specific and valuable information about the hypermethylation in gene as a preventive and diagnostics tools for the personalized medicine; as that the tumor-suppresser-genes have relative co-expression and complementary relations which the hypermethylation affect in the samples studied in our work. Copyright © 2018. Published by Elsevier B.V.

  12. Tumor Restrictive Suicide Gene Therapy for Glioma Controlled by the FOS Promoter.

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    Jianqing Pan

    Full Text Available Effective suicide gene delivery and expression are crucial to achieving successful effects in gene therapy. An ideal tumor-specific promoter expresses therapeutic genes in tumor cells with minimal normal tissue expression. We compared the activity of the FOS (FBJ murine osteosarcoma viral oncogene homolog promoter with five alternative tumor-specific promoters in glioma cells and non-malignant astrocytes. The FOS promoter caused significantly higher transcriptional activity in glioma cell lines than all alternative promoters with the exception of CMV. The FOS promoter showed 13.9%, 32.4%, and 70.8% of the transcriptional activity of CMV in three glioma cell lines (U87, U251, and U373. Importantly, however, the FOS promoter showed only 1.6% of the transcriptional activity of CMV in normal astrocytes. We also tested the biologic activity of recombinant adenovirus containing the suicide gene herpes simplex virus thymidine kinase (HSV-tk driven by the FOS promoter, including selective killing efficacy in vitro and tumor inhibition rate in vivo. Adenoviral-mediated delivery of the HSV-tk gene controlled by the FOS promoter conferred a cytotoxic effect on human glioma cells in vitro and in vivo. This study suggests that use of the FOS-tk adenovirus system is a promising strategy for glioma-specific gene therapy but still much left for improvement.

  13. Tumor suppressor genes that escape from X-inactivation contribute to cancer sex bias

    Science.gov (United States)

    Dunford, Andrew; Weinstock, David M.; Savova, Virginia; Schumacher, Steven E.; Cleary, John P.; Yoda, Akinori; Sullivan, Timothy J.; Hess, Julian M.; Gimelbrant, Alexander A.; Beroukhim, Rameen; Lawrence, Michael S.; Getz, Gad; Lane, Andrew A.

    2016-01-01

    There is a striking and unexplained male predominance across many cancer types. A subset of X chromosome (chrX) genes can escape X-inactivation, which would protect females from complete functional loss by a single mutation. To identify putative “Escape from X-Inactivation Tumor Suppressor” (EXITS) genes, we compared somatic alterations from >4100 cancers across 21 tumor types for sex bias. Six of 783 non-pseudoautosomal region (PAR) chrX genes (ATRX, CNKSR2, DDX3X, KDM5C, KDM6A, and MAGEC3) more frequently harbored loss-of-function mutations in males (based on false discovery rate <0.1), compared to zero of 18,055 autosomal and PAR genes (P<0.0001). Male-biased mutations in genes that escape X-inactivation were observed in combined analysis across many cancers and in several individual tumor types, suggesting a generalized phenomenon. We conclude that biallelic expression of EXITS genes in females explains a portion of the reduced cancer incidence compared to males across a variety of tumor types. PMID:27869828

  14. Tumor-suppressor genes that escape from X-inactivation contribute to cancer sex bias.

    Science.gov (United States)

    Dunford, Andrew; Weinstock, David M; Savova, Virginia; Schumacher, Steven E; Cleary, John P; Yoda, Akinori; Sullivan, Timothy J; Hess, Julian M; Gimelbrant, Alexander A; Beroukhim, Rameen; Lawrence, Michael S; Getz, Gad; Lane, Andrew A

    2017-01-01

    There is a striking and unexplained male predominance across many cancer types. A subset of X-chromosome genes can escape X-inactivation, which would protect females from complete functional loss by a single mutation. To identify putative 'escape from X-inactivation tumor-suppressor' (EXITS) genes, we examined somatic alterations from >4,100 cancers across 21 tumor types for sex bias. Six of 783 non-pseudoautosomal region (PAR) X-chromosome genes (ATRX, CNKSR2, DDX3X, KDM5C, KDM6A, and MAGEC3) harbored loss-of-function mutations more frequently in males (based on a false discovery rate < 0.1), in comparison to zero of 18,055 autosomal and PAR genes (Fisher's exact P < 0.0001). Male-biased mutations in genes that escape X-inactivation were observed in combined analysis across many cancers and in several individual tumor types, suggesting a generalized phenomenon. We conclude that biallelic expression of EXITS genes in females explains a portion of the reduced cancer incidence in females as compared to males across a variety of tumor types.

  15. Mutations in the hedgehog pathway genes SMO and PTCH1 in human gastric tumors.

    Directory of Open Access Journals (Sweden)

    Xi-De Wang

    Full Text Available The causal role of the hedgehog pathway in cancer has been best documented in basal cell carcinoma of the skin. To assess potential DNA alterations of the hedgehog pathway in gastric cancer, we sequenced SMO and PTCH1 genes in a set of 39 gastric tumors. Tumors were classified by histology based on the Lauren classification and Sanger sequencing was performed to obtain full length coding sequences. Genomic instability was evident in these tumors as a number of silent or missense mutations were found. In addition to those that are potential germline polymorphisms, we found three SMO missense mutations, and one PTCH1 frameshift mutation that are novel and have not been documented in basal cell carcinoma. Mutations were found in both intestinal and diffuse type gastric tumors as well as in tumors that exhibit both intestinal and diffuse features. mRNA expression of hedgehog pathway genes was also examined and their levels do not indicate unequivocal higher pathway activity in tumors with mutations than those without. In summary, SMO and/or PTCH1 mutations are present at low frequency in different histologic subtypes of gastric tumors and these do not appear to be driver mutations.

  16. Profiling of oligosaccharides and p53 gene mutation in Filipino breast tumors

    International Nuclear Information System (INIS)

    Deocaris, Custer C.; De Vera, Azucena C.; Magno, Jose Donato A.; Cruz, Michael Joseph B.; Prodigalidad, Abelardo-Alan T.; Jacinto, Sonia D.

    2010-01-01

    Majority of patients are diagnosed with benign tumors, however, such benign tumors can progress to an invasive disease. Since carbohydrate-mediated cell-cell adhesion and proliferative potential play crucial roles in tumorigenesis and tumor aggressive behavior, we analyzed the qualitative changes in oligosaccharide expression and analyzed for presence of mutation in the tumor suppressor p53 gene, the most mutated gene in all human cancers. Forty-three (43) breast tumors were screened for p53 mutation in exons 2-11 using polymerase chain reaction (PCR)-amplification coupled to temporal temperature gradient electrophoresis (TTGE). Paraffin-embedded tissues were stained with biotinylated-glycoproteins containing the following sugar groups: mannose (Man), lactose (Lac), fucoidan (Fuc), N-acetyl-glucosamine (GlcNac), N-acetyl-b-galactosamine (GalNAc) and hyaluronic acid (Hya). Expression of carbohydrate receptors was significantly elevated (p=0.003) in malignant compared with benign tumors, particularly at receptors for GalNAc, lac and Fuc. No change in overall glycan signatures using our panel of neoglycoconjugates was noted when grouped according to p53 mutation status in both benign and malignant cases. Although the prognostic value of carbohydrate-receptors in breast cancer has not been validated to date, our results indicate that benign and malignant tumors can be defined by their affinities to our battery of neoglyconjugates. However, result from our reverse lectin histochemistry failed to correlated glycan signature with presence of p53 mutations. (author)

  17. Effect of surgical procedures on prostate tumor gene expression profiles.

    Science.gov (United States)

    Li, Jie; Zhang, Zhi-Hong; Yin, Chang-Jun; Pavlovich, Christian; Luo, Jun; Getzenberg, Robert; Zhang, Wei

    2012-09-01

    Current surgical treatment of prostate cancer is typically accomplished by either open radical prostatectomy (ORP) or robotic-assisted laparoscopic radical prostatectomy (RALRP). Intra-operative procedural differences between the two surgical approaches may alter the molecular composition of resected surgical specimens, which are indispensable for molecular analysis and biomarker evaluation. The objective of this study is to investigate the effect of different surgical procedures on RNA quality and genome-wide expression signature. RNA integrity number (RIN) values were compared between total RNA samples extracted from consecutive LRP (n=11) and ORP (n=24) prostate specimens. Expression profiling was performed using the Agilent human whole-genome expression microarrays. Expression differences by surgical type were analyzed by Volcano plot analysis and gene ontology analysis. Quantitative reverse transcription (RT)-PCR was used for expression validation in an independent set of LRP (n=8) and ORP (n=8) samples. The LRP procedure did not compromise RNA integrity. Differential gene expression by surgery types was limited to a small subset of genes, the number of which was smaller than that expected by chance. Unexpectedly, this small subset of differentially expressed genes was enriched for those encoding transcription factors, oxygen transporters and other previously reported surgery-induced stress-response genes, and demonstrated unidirectional reduction in LRP specimens in comparison to ORP specimens. The effect of the LRP procedure on RNA quality and genome-wide transcript levels is negligible, supporting the suitability of LRP surgical specimens for routine molecular analysis. Blunted in vivo stress response in LRP specimens, likely mediated by CO(2) insufflation but not by longer ischemia time, is manifested in the reduced expression of stress-response genes in these specimens.

  18. Differences in gene expression between sonoporation in tumor and in muscle.

    Science.gov (United States)

    Tsai, Kun-Che; Liao, Zhe-Kang; Yang, Shu-Jyuan; Lin, Win-Li; Shieh, Ming-Jium; Hwang, Lih-Hwa; Chen, Wen-Shiang

    2009-10-01

    Ultrasound (US) is a novel and effective tool for the local delivery of genes into target tissues. US can temporarily change the permeability of a cell membrane and thus enhance the delivery of naked DNA into cells. In the present study, the efficiencies of gene expression mediated by US delivery in orthotopic liver tumor, subcutaneous tumor and muscle tissue were evaluated by changing the contrast agent concentrations and US exposure durations. Plasmid DNA coding for luciferase, interleukin-12 or enhanced green fluorescence protein was mixed with SonoVue and injected intratumorally or intramuscularly. The injection sites were then exposed to US (20% duty cycle and 0.4 W/cm(2) intensity). The results obtained showed that the optimal condition was 50% SonoVue for tumors and 30% for muscle, with 10 min of US exposure. The expression levels of the transfected DNAs were in the order: muscle > subcutaneous tumor > orthotopic liver tumor. The present study indicates that muscle tissue is a good target site for producing large amounts of gene products for the purpose of gene therapy.

  19. Mutational hotspots in the TP53 gene and, possibly, other tumor suppressors evolve by positive selection

    Directory of Open Access Journals (Sweden)

    Koonin Eugene V

    2006-01-01

    Full Text Available Abstract Background The mutation spectra of the TP53 gene and other tumor suppressors contain multiple hotspots, i.e., sites of non-random, frequent mutation in tumors and/or the germline. The origin of the hotspots remains unclear, the general view being that they represent highly mutable nucleotide contexts which likely reflect effects of different endogenous and exogenous factors shaping the mutation process in specific tissues. The origin of hotspots is of major importance because it has been suggested that mutable contexts could be used to infer mechanisms of mutagenesis contributing to tumorigenesis. Results Here we apply three independent tests, accounting for non-uniform base compositions in synonymous and non-synonymous sites, to test whether the hotspots emerge via selection or due to mutational bias. All three tests consistently indicate that the hotspots in the TP53 gene evolve, primarily, via positive selection. The results were robust to the elimination of the highly mutable CpG dinucleotides. By contrast, only one, the least conservative test reveals the signature of positive selection in BRCA1, BRCA2, and p16. Elucidation of the origin of the hotspots in these genes requires more data on somatic mutations in tumors. Conclusion The results of this analysis seem to indicate that positive selection for gain-of-function in tumor suppressor genes is an important aspect of tumorigenesis, blurring the distinction between tumor suppressors and oncogenes. Reviewers This article was reviewed by Sandor Pongor, Christopher Lee and Mikhail Blagosklonny.

  20. Hypermethylation Of The Tumor Suppressor RASSF1A Gene In ...

    African Journals Online (AJOL)

    Breast cancer is the leading cancer among females. There is a critical need for improved molecular biomarkers that are diagnostic, prognostic and also capable of predicting the progression of benign high-risk lesions to invasive carcinoma. RAS association domain family protein 1A (RASSF1A) gene, is a biologically ...

  1. Bioinformatic screening of human ESTs for differentially expressed genes in normal and tumor tissues

    Directory of Open Access Journals (Sweden)

    Mouchiroud Dominique

    2006-04-01

    Full Text Available Abstract Background Owing to the explosion of information generated by human genomics, analysis of publicly available databases can help identify potential candidate genes relevant to the cancerous phenotype. The aim of this study was to scan for such genes by whole-genome in silico subtraction using Expressed Sequence Tag (EST data. Methods Genes differentially expressed in normal versus tumor tissues were identified using a computer-based differential display strategy. Bcl-xL, an anti-apoptotic member of the Bcl-2 family, was selected for confirmation by western blot analysis. Results Our genome-wide expression analysis identified a set of genes whose differential expression may be attributed to the genetic alterations associated with tumor formation and malignant growth. We propose complete lists of genes that may serve as targets for projects seeking novel candidates for cancer diagnosis and therapy. Our validation result showed increased protein levels of Bcl-xL in two different liver cancer specimens compared to normal liver. Notably, our EST-based data mining procedure indicated that most of the changes in gene expression observed in cancer cells corresponded to gene inactivation patterns. Chromosomes and chromosomal regions most frequently associated with aberrant expression changes in cancer libraries were also determined. Conclusion Through the description of several candidates (including genes encoding extracellular matrix and ribosomal components, cytoskeletal proteins, apoptotic regulators, and novel tissue-specific biomarkers, our study illustrates the utility of in silico transcriptomics to identify tumor cell signatures, tumor-related genes and chromosomal regions frequently associated with aberrant expression in cancer.

  2. A Patient With Desmoid Tumors and Familial FAP Having Frame Shift Mutation of the APC Gene

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    Sanambar Sadighi

    2017-02-01

    Full Text Available Desmoids tumors, characterized by monoclonal proliferation of myofibroblasts, could occur in 5-10% of patients with familial adenomatous polyposis (FAP as an extra-colonic manifestation of the disease. FAP can develop when there is a germ-line mutation in the adenomatous polyposis coli gene. Although mild or attenuated FAP may follow mutations in 5΄ extreme of the gene, it is more likely that 3΄ extreme mutations haveamore severe manifestation of thedisease. A 28-year-old woman was admitted to the Cancer Institute of Iran with an abdominal painful mass. She had strong family history of FAP and underwent prophylactic total colectomy. Pre-operative CT scans revealed a large mass. Microscopic observation showed diffuse fibroblast cell infiltration of the adjacent tissue structures. Peripheral blood DNA extraction followed by adenomatous polyposis coli gene exon by exon sequencing was performed to investigate the mutation in adenomatous polyposis coli gene. Analysis of DNA sequencing demonstrated a mutation of 4 bpdeletions at codon 1309-1310 of the exon 16 of adenomatous polyposis coli gene sequence which was repeated in 3 members of the family. Some of them had desmoid tumor without classical FAP history. Even when there is no familial history of adenomatous polyposis, the adenomatous polyposis coli gene mutation should be investigated in cases of familial desmoids tumors for a suitable prevention. The 3΄ extreme of the adenomatous polyposis coli gene is still the best likely location in such families.

  3. Implementation of plaid model biclustering method on microarray of carcinoma and adenoma tumor gene expression data

    Science.gov (United States)

    Ardaneswari, Gianinna; Bustamam, Alhadi; Sarwinda, Devvi

    2017-10-01

    A Tumor is an abnormal growth of cells that serves no purpose. Carcinoma is a tumor that grows from the top of the cell membrane and the organ adenoma is a benign tumor of the gland-like cells or epithelial tissue. In the field of molecular biology, the development of microarray technology is used in the data store of disease genetic expression. For each of microarray gene, an amount of information is stored for each trait or condition. In gene expression data clustering can be done with a bicluster algorithm, thats clustering method which not only the objects to be clustered, but also the properties or condition of the object. This research proposed Plaid Model Biclustering as one of biclustering method. In this study, we discuss the implementation of Plaid Model Biclustering Method on microarray of Carcinoma and Adenoma tumor gene expression data. From the experimental results, we found three biclusters are formed by Carcinoma gene expression data and four biclusters are formed by Adenoma gene expression data.

  4. Quantitative gene-expression of the tumor angiogenesis markers vascular endothelial growth factor, integrin alphaV and integrin beta3 in human neuroendocrine tumors

    DEFF Research Database (Denmark)

    Oxboel, Jytte; Binderup, Tina; Knigge, Ulrich

    2009-01-01

    compared to both colorectal liver metastases (p=0.10) and normal liver tissue (p=0.06). In neuroendocrine tumors, gene-expression was highly variable of VEGF (530-fold), integrin alphaV (23-fold) and integrin beta3 (106-fold). Quantitative gene-expression levels of the key angiogenesis molecules VEGF......, in neuroendocrine tumors. We used quantitative real-time PCR for measuring mRNA gene-expression of vascular endothelial growth factor (VEGF), integrin alphaV, and integrin beta3, and CD34 for a group of patients with neuroendocrine tumors (n=13). Tissue from patients with colorectal cancer liver metastases (n=14......) and normal liver tissues (n=16) was used as control. We found a lower mRNA level of VEGF in neuroendocrine tumors compared to both colorectal liver metastases (pbeta3 there was also a borderline significant lower level of mRNA in neuroendocrine tumors...

  5. Indications for a tumor suppressor gene at 22q11 involved in the pathogenesis of ependymal tumors and distinct from hSNF5/INI1.

    Science.gov (United States)

    Kraus, J A; de Millas, W; Sörensen, N; Herbold, C; Schichor, C; Tonn, J C; Wiestler, O D; von Deimling, A; Pietsch, T

    2001-07-01

    Ependymomas account for approximately 9% of all neuroepithelial tumors and represent the most frequent neuroepithelial tumors of the spinal cord. In adults, allelic loss of chromosome arm 22q occurs in up to 60% of the cases studied. Some of these tumors show an altered neurofibromatosis type 2 (NF2) gene; in others, NF2 appears to be unaffected, indicating the involvement of another tumor suppressor gene. Recently, the tumor suppressor gene hSNF5/INI1, located on 22q11.23, has been shown to contribute to the pathogenesis of renal and extrarenal rhabdoid tumors. In addition, this gene may be responsible for a new hereditary syndrome predisposing to a variety of tumors designated "rhabdoid predisposition syndrome." In the present study, we analyzed a series of 53 ependymal tumors of 48 patients [4 myxopapillary ependymomas (WHO grade I), 3 subependymomas (WHO grade I), 18 ependymomas (WHO grade II), 21 anaplastic ependymomas (WHO grade III) and 2 ependymoblastomas (WHO grade IV)] for mutations and homozygous deletions in the coding region of the hSNF5/INI1 gene and for allelic loss of its flanking chromosomal regions in 39 ependymal tumors of 35 patients. Allelic loss was detected in 11 of 35 informative primary ependymal tumors (31%) with a common region of overlap covered by the markers D22S257 and D22S310 on 22q11 including the marker D22S301. However, a detailed molecular analysis of 53 ependymal tumors for mutations and homozygous deletion of the hSNF5/INI1 gene revealed no alterations. We conclude that the hSNF5/INI1 gene is not involved in the pathogenesis of human ependymal tumors with allelic loss on chromosome arm 22q and an intact NF2 locus. In addition, our study localizes a putative ependymoma tumor suppressor gene(s) to a domain of chromosome arm 22q flanked by the microsatellite markers D22S257 and D22S310.

  6. Generation of two modified mouse alleles of the Hic1 tumor suppressor gene

    Czech Academy of Sciences Publication Activity Database

    Pospíchalová, Vendula; Turečková, Jolana; Fafílek, Bohumil; Vojtěchová, Martina; Krausová, Michaela; Lukáš, Jan; Šloncová, Eva; Takacova, S.; Divoký, V.; Leprince, D.; Plachý, Jiří; Kořínek, Vladimír

    2011-01-01

    Roč. 49, č. 3 (2011), s. 142-151 ISSN 1526-954X R&D Projects: GA ČR(CZ) GA204/07/1567; GA ČR(CZ) GD204/09/H058 Institutional research plan: CEZ:AV0Z50520514 Keywords : Hypermethylated In Cancer 1 * Hic1 tumor suppressor * gene targeting Subject RIV: EB - Gene tics ; Molecular Biology Impact factor: 2.527, year: 2011

  7. The Multi-Purpose Tool of Tumor Immunotherapy: Gene-Engineered T Cells.

    Science.gov (United States)

    Mo, Zeming; Du, Peixin; Wang, Guoping; Wang, Yongsheng

    2017-01-01

    A detailed summary of the published clinical trials of chimeric antigen receptor T cells (CAR-T) and TCR-transduced T cells (TCR-T) was constructed to understand the development trend of adoptive T cell therapy (ACT). In contrast to TCR-T, the number of CAR-T clinical trials has increased dramatically in China in the last three years. The ACT seems to be very prosperous. But, the multidimensional interaction of tumor, tumor associated antigen (TAA) and normal tissue exacerbates the uncontrolled outcome of T cells gene therapy. It reminds us the importance that optimizing treatment security to prevent the fatal serious adverse events. How to balance the safety and effectiveness of the ACT? At least six measures can potentially optimize the safety of ACT. At the same time, with the application of gene editing techniques, more endogenous receptors are disrupted while more exogenous receptors are expressed on T cells. As a multi-purpose tool of tumor immunotherapy, gene-engineered T cells (GE-T) have been given different functional weapons. A network which is likely to link radiation therapy, tumor vaccines, CAR-T and TCR-T is being built. Moreover, more and more evidences indicated that the combination of the ACT and other therapies would further enhance the anti-tumor capacity of the GE-T.

  8. Single-Cell RNA Sequencing Identifies Extracellular Matrix Gene Expression by Pancreatic Circulating Tumor Cells

    Directory of Open Access Journals (Sweden)

    David T. Ting

    2014-09-01

    Full Text Available Circulating tumor cells (CTCs are shed from primary tumors into the bloodstream, mediating the hematogenous spread of cancer to distant organs. To define their composition, we compared genome-wide expression profiles of CTCs with matched primary tumors in a mouse model of pancreatic cancer, isolating individual CTCs using epitope-independent microfluidic capture, followed by single-cell RNA sequencing. CTCs clustered separately from primary tumors and tumor-derived cell lines, showing low-proliferative signatures, enrichment for the stem-cell-associated gene Aldh1a2, biphenotypic expression of epithelial and mesenchymal markers, and expression of Igfbp5, a gene transcript enriched at the epithelial-stromal interface. Mouse as well as human pancreatic CTCs exhibit a very high expression of stromal-derived extracellular matrix (ECM proteins, including SPARC, whose knockdown in cancer cells suppresses cell migration and invasiveness. The aberrant expression by CTCs of stromal ECM genes points to their contribution of microenvironmental signals for the spread of cancer to distant organs.

  9. Single-cell RNA sequencing identifies extracellular matrix gene expression by pancreatic circulating tumor cells.

    Science.gov (United States)

    Ting, David T; Wittner, Ben S; Ligorio, Matteo; Vincent Jordan, Nicole; Shah, Ajay M; Miyamoto, David T; Aceto, Nicola; Bersani, Francesca; Brannigan, Brian W; Xega, Kristina; Ciciliano, Jordan C; Zhu, Huili; MacKenzie, Olivia C; Trautwein, Julie; Arora, Kshitij S; Shahid, Mohammad; Ellis, Haley L; Qu, Na; Bardeesy, Nabeel; Rivera, Miguel N; Deshpande, Vikram; Ferrone, Cristina R; Kapur, Ravi; Ramaswamy, Sridhar; Shioda, Toshi; Toner, Mehmet; Maheswaran, Shyamala; Haber, Daniel A

    2014-09-25

    Circulating tumor cells (CTCs) are shed from primary tumors into the bloodstream, mediating the hematogenous spread of cancer to distant organs. To define their composition, we compared genome-wide expression profiles of CTCs with matched primary tumors in a mouse model of pancreatic cancer, isolating individual CTCs using epitope-independent microfluidic capture, followed by single-cell RNA sequencing. CTCs clustered separately from primary tumors and tumor-derived cell lines, showing low-proliferative signatures, enrichment for the stem-cell-associated gene Aldh1a2, biphenotypic expression of epithelial and mesenchymal markers, and expression of Igfbp5, a gene transcript enriched at the epithelial-stromal interface. Mouse as well as human pancreatic CTCs exhibit a very high expression of stromal-derived extracellular matrix (ECM) proteins, including SPARC, whose knockdown in cancer cells suppresses cell migration and invasiveness. The aberrant expression by CTCs of stromal ECM genes points to their contribution of microenvironmental signals for the spread of cancer to distant organs. Copyright © 2014 The Authors. Published by Elsevier Inc. All rights reserved.

  10. Correlation of SHOX2 Gene Amplification and DNA Methylation in Lung Cancer Tumors

    International Nuclear Information System (INIS)

    Schneider, Katja U; Liebenberg, Volker; Kneip, Christoph; Seegebarth, Anke; Erdogan, Fikret; Rappold, Gudrun; Schmidt, Bernd; Dietrich, Dimo; Fleischhacker, Michael; Leschber, Gunda; Merk, Johannes; Schäper, Frank; Stapert, Henk R; Vossenaar, Erik R; Weickmann, Sabine

    2011-01-01

    DNA methylation in the SHOX2 locus was previously used to reliably detect lung cancer in a group of critical controls, including 'cytologically negative' samples with no visible tumor cell content, at a high specificity based on the analysis of bronchial lavage samples. This study aimed to investigate, if the methylation correlates with SHOX2 gene expression and/or copy number alterations. An amplification of the SHOX2 gene locus together with the observed tumor-specific hypermethylation might explain the good performance of this marker in bronchial lavage samples. SHOX2 expression, gene copy number and DNA methylation were determined in lung tumor tissues and matched morphologically normal adjacent tissues (NAT) from 55 lung cancer patients. Quantitative HeavyMethyl (HM) real-time PCR was used to detect SHOX2 DNA methylation levels. SHOX2 expression was assayed with quantitative real-time PCR, and copy numbers alterations were measured with conventional real-time PCR and array CGH. A hypermethylation of the SHOX2 locus in tumor tissue as compared to the matched NAT from the same patient was detected in 96% of tumors from a group of 55 lung cancer patients. This correlated highly significantly with the frequent occurrence of copy number amplification (p < 0.0001), while the expression of the SHOX2 gene showed no difference. Frequent gene amplification correlated with hypermethylation of the SHOX2 gene locus. This concerted effect qualifies SHOX2 DNA methylation as a biomarker for lung cancer diagnosis, especially when sensitive detection is needed, i.e. in bronchial lavage or blood samples

  11. Gene expression analysis of matched ovarian primary tumors and peritoneal metastasis

    Directory of Open Access Journals (Sweden)

    Malek Joel A

    2012-06-01

    Full Text Available Abstract Background Ovarian cancer is the most deadly gynecological cancer due to late diagnosis at advanced stage with major peritoneal involvement. To date most research has focused on primary tumor. However the prognosis is directly related to residual disease at the end of the treatment. Therefore it is mandatory to focus and study the biology of meatastatic disease that is most frequently localized to the peritoneal caivty in ovarian cancer. Methods We used high-density gene expression arrays to investigate gene expression changes between matched primary and metastatic (peritoneal lesions. Results Here we show that gene expression profiles in peritoneal metastasis are significantly different than their matched primary tumor and these changes are affected by underlying copy number variation differences among other causes. We show that differentially expressed genes are enriched in specific pathways including JAK/STAT pathway, cytokine signaling and other immune related pathways. We show that underlying copy number variations significantly affect gene expression. Indeed patients with important differences in copy number variation displayed greater gene expression differences between their primary and matched metastatic lesions. Conclusions Our analysis shows a very specific targeting at both the genomic and transcriptomic level to upregulate certain pathways in the peritoneal metastasis of ovarian cancer. Moreover, while primary tumors use certain pathways we identify distinct differences with metastatic lesions. The variation between primary and metastatic lesions should be considered in personalized treatment of ovarian cancer.

  12. Tumoral tissue specific promoter hypermethylation of distinct tumor suppressor genes in a case with non--small cell lung carcinoma: A case report

    Directory of Open Access Journals (Sweden)

    Arslan Sulhattin

    2008-01-01

    Full Text Available Objective: Non-small cell lung carcinoma is an aggressive phenomenon and the epigenetical alterations of some tumor supressor genes have been reported for the different tumor types. Case Presentation: It is presented a case report concerning a 43 years old male with NSCLC on the lower segment of the right lung. The patient underwent a diag-nostic excisional thin-needle biopsy and after the histological confirmation. We examined the promoter methylation status of some distinct tumor supressor genes in tumoral and blood tissues of the case after sodium bisulfite conversion and DNA amplification with methylation specific multiplex PCR technique. Both tissues were also searched for G to A transitions in codons 12 and 13 of the K-ras proto-oncogene. Results: Tumor specimen showed fully methyl pattern profiles for the SFRP2, p16, DAPK1 and partially hyper-methylated profile for the p53 and MGMT genes in this case with non-small lung carci-noma. Blood speicemen showed normal hypomethylated profiles for all studied TS genes. The K-ras proto-oncogene was in normal structure both in blood and tumoral spiecemens that examined. Conclusion: Results indicate that genes exhibit tumor suppressor activi-ties in blood, but exhibit epigenetic inactivation in carcinoma cell. These findings strongly support the hypothesis that epigenetic mechanisms may play an important role in the non-small cell lung carcinogenesis in human.

  13. Expression of iron-related genes in human brain and brain tumors

    Directory of Open Access Journals (Sweden)

    Britton Robert S

    2009-04-01

    Full Text Available Abstract Background Defective iron homeostasis may be involved in the development of some diseases within the central nervous system. Although the expression of genes involved in normal iron balance has been intensively studied in other tissues, little is known about their expression in the brain. We investigated the mRNA levels of hepcidin (HAMP, HFE, neogenin (NEO1, transferrin receptor 1 (TFRC, transferrin receptor 2 (TFR2, and hemojuvelin (HFE2 in normal human brain, brain tumors, and astrocytoma cell lines. The specimens included 5 normal brain tissue samples, 4 meningiomas, one medulloblastoma, 3 oligodendrocytic gliomas, 2 oligoastrocytic gliomas, 8 astrocytic gliomas, and 3 astrocytoma cell lines. Results Except for hemojuvelin, all genes studied had detectable levels of mRNA. In most tumor types, the pattern of gene expression was diverse. Notable findings include high expression of transferrin receptor 1 in the hippocampus and medulla oblongata compared to other brain regions, low expression of HFE in normal brain with elevated HFE expression in meningiomas, and absence of hepcidin mRNA in astrocytoma cell lines despite expression in normal brain and tumor specimens. Conclusion These results indicate that several iron-related genes are expressed in normal brain, and that their expression may be dysregulated in brain tumors.

  14. Molecular characterization of the porcine deleted in malignant brain tumors 1 gene (DMBT1)

    DEFF Research Database (Denmark)

    Haase, Bianca; Humphray, Sean J; Lyer, Stefan

    2006-01-01

    The human gene deleted in malignant brain tumors 1 (DMBT1) is considered to play a role in tumorigenesis and pathogen defense. It encodes a protein with multiple scavenger receptor cysteine-rich (SRCR) domains, which are involved in recognition and binding of a broad spectrum of bacterial pathogens...

  15. Haploinsufficiency of the genes encoding the tumor suppressor Pten predisposes zebrafish to hemangiosarcoma

    NARCIS (Netherlands)

    Choorapoikayil, S.; Kuiper, R.V.; de Bruin, A.; den Hertog, J.

    2012-01-01

    PTEN is an essential tumor suppressor that antagonizes Akt/PKB signaling. The zebrafish genome encodes two Pten genes, ptena and ptenb. Here, we report that zebrafish mutants that retain a single wild-type copy of ptena or ptenb (ptena(+/-)ptenb(-/-) or ptena(-/-)ptenb(+/-)) are viable and fertile.

  16. Positional cloning of genes involved in the Beckwith-Wiedemann syndrome, hemihypertrophy, and associated childhood tumors

    NARCIS (Netherlands)

    Mannens, M.; Alders, M.; Redeker, B.; Bliek, J.; Steenman, M.; Wiesmeyer, C.; de Meulemeester, M.; Ryan, A.; Kalikin, L.; Voûte, T.; de Kraker, J.; Hoovers, J.; Slater, R.; Feinberg, A.; Little, P.; Westerveld, A.

    1996-01-01

    The Beckwith-Wiedemann syndrome (BWS) is an overgrowth malformation syndrome that occurs with an incidence of 1:13,700 births. There is a striking incidence of childhood tumors found in BWS patients. Various lines of investigation have localized "imprinted" genes involved in BWS and associated

  17. Analyses of tumor-suppressor genes in germline mouse models of cancer.

    Science.gov (United States)

    Wang, Jingqiang; Abate-Shen, Cory

    2014-08-01

    Tumor-suppressor genes are critical regulators of growth and functioning of cells, whose loss of function contributes to tumorigenesis. Accordingly, analyses of the consequences of their loss of function in genetically engineered mouse models have provided important insights into mechanisms of human cancer, as well as resources for preclinical analyses and biomarker discovery. Nowadays, most investigations of genetically engineered mouse models of tumor-suppressor function use conditional or inducible alleles, which enable analyses in specific cancer (tissue) types and overcome the consequences of embryonic lethality of germline loss of function of essential tumor-suppressor genes. However, historically, analyses of genetically engineered mouse models based on germline loss of function of tumor-suppressor genes were very important as these early studies established the principle that loss of function could be studied in mouse cancer models and also enabled analyses of these essential genes in an organismal context. Although the cancer phenotypes of these early germline models did not always recapitulate the expected phenotypes in human cancer, these models provided the essential foundation for the more sophisticated conditional and inducible models that are currently in use. Here, we describe these "first-generation" germline models of loss of function models, focusing on the important lessons learned from their analyses, which helped in the design and analyses of "next-generation" genetically engineered mouse models. © 2014 Cold Spring Harbor Laboratory Press.

  18. Tumor suppressor gene-based nanotherapy: from test tube to the clinic.

    Science.gov (United States)

    Shanker, Manish; Jin, Jiankang; Branch, Cynthia D; Miyamoto, Shinya; Grimm, Elizabeth A; Roth, Jack A; Ramesh, Rajagopal

    2011-01-01

    Cancer is a major health problem in the world. Advances made in cancer therapy have improved the survival of patients in certain types of cancer. However, the overall five-year survival has not significantly improved in the majority of cancer types. Major challenges encountered in having effective cancer therapy are development of drug resistance by the tumor cells, nonspecific cytotoxicity, and inability to affect metastatic tumors by the chemodrugs. Overcoming these challenges requires development and testing of novel therapies. One attractive cancer therapeutic approach is cancer gene therapy. Several laboratories including the authors' laboratory have been investigating nonviral formulations for delivering therapeutic genes as a mode for effective cancer therapy. In this paper the authors will summarize their experience in the development and testing of a cationic lipid-based nanocarrier formulation and the results from their preclinical studies leading to a Phase I clinical trial for nonsmall cell lung cancer. Their nanocarrier formulation containing therapeutic genes such as tumor suppressor genes when administered intravenously effectively controls metastatic tumor growth. Additional Phase I clinical trials based on the results of their nanocarrier formulation have been initiated or proposed for treatment of cancer of the breast, ovary, pancreas, and metastatic melanoma, and will be discussed.

  19. Tumor Suppressor Gene-Based Nanotherapy: From Test Tube to the Clinic

    Directory of Open Access Journals (Sweden)

    Manish Shanker

    2011-01-01

    Full Text Available Cancer is a major health problem in the world. Advances made in cancer therapy have improved the survival of patients in certain types of cancer. However, the overall five-year survival has not significantly improved in the majority of cancer types. Major challenges encountered in having effective cancer therapy are development of drug resistance by the tumor cells, nonspecific cytotoxicity, and inability to affect metastatic tumors by the chemodrugs. Overcoming these challenges requires development and testing of novel therapies. One attractive cancer therapeutic approach is cancer gene therapy. Several laboratories including the authors' laboratory have been investigating nonviral formulations for delivering therapeutic genes as a mode for effective cancer therapy. In this paper the authors will summarize their experience in the development and testing of a cationic lipid-based nanocarrier formulation and the results from their preclinical studies leading to a Phase I clinical trial for nonsmall cell lung cancer. Their nanocarrier formulation containing therapeutic genes such as tumor suppressor genes when administered intravenously effectively controls metastatic tumor growth. Additional Phase I clinical trials based on the results of their nanocarrier formulation have been initiated or proposed for treatment of cancer of the breast, ovary, pancreas, and metastatic melanoma, and will be discussed.

  20. Molecular Biology In Young Women With Breast Cancer: From Tumor Gene Expression To DNA Mutations.

    Science.gov (United States)

    Gómez-Flores-Ramos, Liliana; Castro-Sánchez, Andrea; Peña-Curiel, Omar; Mohar-Betancourt, Alejandro

    2017-01-01

    Young women with breast cancer (YWBC) represent roughly 15% of breast cancer (BC) cases in Latin America and other developing regions. Breast tumors occurring at an early age are more aggressive and have an overall worse prognosis compared to breast tumors in postmenopausal women. The expression of relevant proliferation biomarkers such as endocrine receptors and human epidermal growth factor receptor 2 appears to be unique in YWBC. Moreover, histopathological, molecular, genetic, and genomic studies have shown that YWBC exhibit a higher frequency of aggressive subtypes, differential tumor gene expression, increased genetic susceptibility, and specific genomic signatures, compared to older women with BC. This article reviews the current knowledge on tumor biology and genomic signatures in YWBC.

  1. Mutations in Exons 9 and 13 of KIT Gene Are Rare Events in Gastrointestinal Stromal Tumors

    Science.gov (United States)

    Lasota, Jerzy; Wozniak, Agnieszka; Sarlomo-Rikala, Maarit; Rys, Janusz; Kordek, Radzislaw; Nassar, Aziza; Sobin, Leslie H.; Miettinen, Markku

    2000-01-01

    Gastrointestinal stromal tumors (GISTs), the most common mesenchymal tumors of the gastrointestinal tract, typically express the KIT protein. Activating mutations in the juxtamembrane domain (exon 11) of the c-kit gene have been shown in a subset of GISTs. These mutations lead into ligand-independent activation of the tyrosine kinase of c-kit, and have a transforming effect in vitro. Several groups have studied the clinical implication of the c-kit mutation status of exon 11 in GISTs and a possible relationship between c-kit mutations and malignant behavior has been established. Recently, a 1530ins6 mutation in exon 9 and missense mutations, 1945A>G in exon 13 of the c-kit gene were reported. The frequency and clinical importance of these findings are unknown. In this study we evaluated 200 GISTs for the presence of mutations in exons 9 and 13 of c-kit. Six cases revealed 1530ins6 mutation in exon 9 and two cases 1945A>G mutation in exon 13. All tumors with mutations in exon 9 and 13 lacked mutations in exon 11 of c-kit. None of the analyzed tumors had more than one type of c-kit mutation. All but one of the eight tumors with mutations in exon 9 or 13 of the c-kit gene were histologically and clinically malignant. All four of six cases with exon 9 mutation of which location of primary tumor was known, were small intestinal, suggesting that this type of mutation could preferentially occur in small intestinal tumors. Exon 9 and 13 mutations seem to be rare, and they cover only a small portion (8%) of the balance of GISTs that do not have mutations in exon 11 of c-kit. This finding indicates that other genetic alterations may activate c-kit in GISTs, or that KIT is not activated by mutations in all cases. PMID:11021812

  2. IL4-induced gene 1 promotes tumor growth by shaping the immune microenvironment in melanoma.

    Science.gov (United States)

    Bod, Lloyd; Lengagne, Renée; Wrobel, Ludovic; Ramspott, Jan Philipp; Kato, Masashi; Avril, Marie-Françoise; Castellano, Flavia; Molinier-Frenkel, Valérie; Prévost-Blondel, Armelle

    2017-01-01

    Amino acid catabolizing enzymes emerged as a crucial mechanism used by tumors to dampen immune responses. The L-phenylalanine oxidase IL-4 induced gene 1 (IL4I1) is expressed by tumor-associated myeloid cells of most solid tumors, including melanoma. We previously provided the only evidence that IL4I1 accelerates tumor growth by limiting the CD8 + T cell mediated immune response, in a mouse model of melanoma cell transplantation. Here, we explored the role of IL4I1 in Ret mice, a spontaneous model of melanoma. We found that IL4I1 was expressed by CD11b + myeloid cells and that its activity correlated with disease aggressiveness. IL4I1 did not enhance tumor cell proliferation or angiogenesis, but orchestrated the remodeling of the immune compartment within the primary tumor. Indeed, the inactivation of IL4I1 limited the recruitment of polymorphonuclear myeloid-derived suppressor cells and enhanced the infiltration by Th1 and cytotoxic T cells, thus delaying tumor development and metastatic dissemination. Accordingly, human primary melanomas that were poorly infiltrated by IL4I1 + cells exhibited a higher density of CD8 + T cells. Collectively, our findings strengthen the rationale for therapeutic targeting of IL4I1 as one of the key immune regulators.

  3. Baculovirus-based gene silencing of Humanin for the treatment of pituitary tumors.

    Science.gov (United States)

    Gottardo, María Florencia; Pidre, Matías L; Zuccato, Camila; Asad, Antonela S; Imsen, Mercedes; Jaita, Gabriela; Candolfi, Marianela; Romanowski, Víctor; Seilicovich, Adriana

    2018-02-01

    Pituitary tumors are the most common primary intracranial neoplasms. Humanin (HN) and Rattin (HNr), a rat homolog of HN, are short peptides with a cytoprotective action. In the present study, we aimed to evaluate whether endogenous HNr plays an antiapoptotic role in pituitary tumor cells. Thus, we used RNA interference based on short-hairpin RNA (shRNA) targeted to HNr (shHNr). A plasmid including the coding sequences for shHNr and dTomato fluorescent reporter gene was developed (pUC-shHNr). Transfection of somatolactotrope GH3 cells with pUC-shHNr increased apoptosis, suggesting that endogenous HNr plays a cytoprotective role in pituitary tumor cells. In order to evaluate the effect of blockade of endogenous HNr expression in vivo, we constructed a recombinant baculovirus (BV) encoding shHNr (BV-shHNr). In vitro, BV-shRNA was capable of transducing more than 80% of GH3 cells and decreased HNr mRNA. Also, BV-shHNr increased apoptosis in transduced GH3 cells. Intratumor injection of BV-shHNr to nude mice bearing s.c. GH3 tumors increased the number of apoptotic cells, delayed tumor growth and enhanced survival rate, suggesting that endogenous HNr may be involved in pituitary tumor progression. These preclinical data suggests that the silencing of HN expression could have a therapeutic impact on the treatment of pituitary tumors.

  4. Hypomethylation and Aberrant Expression of the Glioma Pathogenesis-Related 1 Gene in Wilms Tumors

    Directory of Open Access Journals (Sweden)

    Laxmi Chilukamarri

    2007-11-01

    Full Text Available Wilms tumors (WTs have a complex etiology, displaying genetic and epigenetic changes, including loss of imprinting (LOI and tumor suppressor gene silencing. To identify new regions of epigenetic perturbation in WTs, we screened kidney and tumor DNA using CpG island (CGI tags associated with cancer-specific DNA methylation changes. One such tag corresponded to a paralog of the glioma pathogenesis-related 1/related to testis-specific, vespid, and pathogenesis proteins 1 (GLIPR1/RTVP-1 gene, previously reported to be a tumor-suppressor gene silenced by hypermethylation in prostate cancer. Here we report methylation analysis of the GLIPR1/RTVP-1 gene in WTs and normal fetal and pediatric kidneys. Hypomethylation of the GLIPR1/RTVP-1 5'-region in WTs relative to normal tissue is observed in 21/24 (87.5% of WTs analyzed. Quantitative analysis of GLIPR1/RTVP-1 expression in 24 WTs showed elevated transcript levels in 16/24 WTs (67%, with 12 WTs displaying in excess of 20-fold overexpression relative to fetal kidney (FK control samples. Immunohistochemical analysis of FK and WT corroborates the RNA expression data and reveals high GLIPR1/RTVP-1 in WT blastemal cells together with variable levels in stromal and epithelial components. Hypomethylation is also evident in the WT precursor lesions and nephrogenic rests (NRs, supporting a role for GLIPR1/RTVP-1 deregulation early in Wilms tumorigenesis. Our data show that, in addition to gene dosage changes arising from LOI and hypermethylation-induced gene silencing, gene activation resulting from hypomethylation is also prevalent in WTs.

  5. Overexpression and amplification of the c-myc gene in mouse tumors induced by chemical and radiations

    International Nuclear Information System (INIS)

    Niwa, Ohtsura; Enoki, Yoshitaka; Yokoro, Kenjiro

    1989-01-01

    We examined expression of the c-myc gene by the dot blot hybridization of total cellular RNA from mouse primary tumors induced by chemicals and radiations. Expression of the c-myc gene was found to be elevated in 69 cases among 177 independently induced tumors of 12 different types. DNA from tumors overexpressing the myc gene was analyzed by Southern blotting. No case of rearrangement was detected. However, amplification of the c-myc gene was found in 7 cases of primary sarcomas. These included 4 cases out of 24 methylcholanthrene-induced sarcomas and 3 cases out of 7 α-tocopherol-induced sacromas. We also analyzed 8 cases of sarcomas induced by radiations, but could not find changes in the gene structure of the c-myc gene. Thus, our data indicate tumor type specificity and agent specificity of c-myc gene amplification. (author)

  6. Genes Associated With Prognosis After Surgery For Malignant Pleural Mesothelioma Promote Tumor Cell Survival In Vitro

    Directory of Open Access Journals (Sweden)

    Sugarbaker David J

    2011-05-01

    Full Text Available Abstract Background Mesothelioma is an aggressive neoplasm with few effective treatments, one being cytoreductive surgery. We previously described a test, based on differential expression levels of four genes, to predict clinical outcome in prospectively consented mesothelioma patients after surgery. In this study, we determined whether any of these four genes could be linked to a cancer relevant phenotype. Methods We conducted a high-throughput RNA inhibition screen to knockdown gene expression levels of the four genes comprising the test (ARHGDIA, COBLL1, PKM2, TM4SF1 in both a human lung-derived normal and a tumor cell line using three different small inhibitory RNA molecules per gene. Successful knockdown was confirmed using quantitative RT-PCR. Detection of statistically significant changes in apoptosis and mitosis was performed using immunological assays and quantified using video-assisted microscopy at a single time-point. Changes in nuclear shape, size, and numbers were used to provide additional support of initial findings. Each experiment was conducted in triplicate. Specificity was assured by requiring that at least 2 different siRNAs produced the observed change in each cell line/time-point/gene/assay combination. Results Knockdown of ARHGDIA, COBLL1, and TM4SF1 resulted in 2- to 4-fold increased levels of apoptosis in normal cells (ARHGDIA only and tumor cells (all three genes. No statistically significant changes were observed in apoptosis after knockdown of PKM2 or for mitosis after knockdown of any gene. Conclusions We provide evidence that ARHGDIA, COBLL1, and TM4SF1 are negative regulators of apoptosis in cultured tumor cells. These genes, and their related intracellular signaling pathways, may represent potential therapeutic targets in mesothelioma.

  7. Genes Associated With Prognosis After Surgery For Malignant Pleural Mesothelioma Promote Tumor Cell Survival In Vitro

    International Nuclear Information System (INIS)

    Gordon, Gavin J; Bueno, Raphael; Sugarbaker, David J

    2011-01-01

    Mesothelioma is an aggressive neoplasm with few effective treatments, one being cytoreductive surgery. We previously described a test, based on differential expression levels of four genes, to predict clinical outcome in prospectively consented mesothelioma patients after surgery. In this study, we determined whether any of these four genes could be linked to a cancer relevant phenotype. We conducted a high-throughput RNA inhibition screen to knockdown gene expression levels of the four genes comprising the test (ARHGDIA, COBLL1, PKM2, TM4SF1) in both a human lung-derived normal and a tumor cell line using three different small inhibitory RNA molecules per gene. Successful knockdown was confirmed using quantitative RT-PCR. Detection of statistically significant changes in apoptosis and mitosis was performed using immunological assays and quantified using video-assisted microscopy at a single time-point. Changes in nuclear shape, size, and numbers were used to provide additional support of initial findings. Each experiment was conducted in triplicate. Specificity was assured by requiring that at least 2 different siRNAs produced the observed change in each cell line/time-point/gene/assay combination. Knockdown of ARHGDIA, COBLL1, and TM4SF1 resulted in 2- to 4-fold increased levels of apoptosis in normal cells (ARHGDIA only) and tumor cells (all three genes). No statistically significant changes were observed in apoptosis after knockdown of PKM2 or for mitosis after knockdown of any gene. We provide evidence that ARHGDIA, COBLL1, and TM4SF1 are negative regulators of apoptosis in cultured tumor cells. These genes, and their related intracellular signaling pathways, may represent potential therapeutic targets in mesothelioma

  8. DNA methylation mediated control of gene expression is critical for development of crown gall tumors.

    Directory of Open Access Journals (Sweden)

    Jochen Gohlke

    Full Text Available Crown gall tumors develop after integration of the T-DNA of virulent Agrobacterium tumefaciens strains into the plant genome. Expression of the T-DNA-encoded oncogenes triggers proliferation and differentiation of transformed plant cells. Crown gall development is known to be accompanied by global changes in transcription, metabolite levels, and physiological processes. High levels of abscisic acid (ABA in crown galls regulate expression of drought stress responsive genes and mediate drought stress acclimation, which is essential for wild-type-like tumor growth. An impact of epigenetic processes such as DNA methylation on crown gall development has been suggested; however, it has not yet been investigated comprehensively. In this study, the methylation pattern of Arabidopsis thaliana crown galls was analyzed on a genome-wide scale as well as at the single gene level. Bisulfite sequencing analysis revealed that the oncogenes Ipt, IaaH, and IaaM were unmethylated in crown galls. Nevertheless, the oncogenes were susceptible to siRNA-mediated methylation, which inhibited their expression and subsequently crown gall growth. Genome arrays, hybridized with methylated DNA obtained by immunoprecipitation, revealed a globally hypermethylated crown gall genome, while promoters were rather hypomethylated. Mutants with reduced non-CG methylation developed larger tumors than the wild-type controls, indicating that hypermethylation inhibits plant tumor growth. The differential methylation pattern of crown galls and the stem tissue from which they originate correlated with transcriptional changes. Genes known to be transcriptionally inhibited by ABA and methylated in crown galls became promoter methylated upon treatment of A. thaliana with ABA. This suggests that the high ABA levels in crown galls may mediate DNA methylation and regulate expression of genes involved in drought stress protection. In summary, our studies provide evidence that epigenetic processes

  9. Molecular studies on the function of tumor suppressor gene in gastrointestinal cancer

    International Nuclear Information System (INIS)

    Kim, You Cheoul

    1993-01-01

    Cancer of stomach, colon and liver are a group of the most common cancer in Korea. However, results with current therapeutic modalities are still unsatisfactory. The intensive efforts have been made to understand basic pathogenesis and to find better therapeutic tools for the treatment of this miserable disease. We studies the alteration of tumor suppressor gene in various Gastrointestinal cancer in Korea. Results showed that genetic alteration of Rb gene was in 83% of colorectal cancer. Our results suggest that genetic alteration of Rb gene is crucially involved in the tumorigenesis of colorectum in Korea. (Author)

  10. Aberrations of the p53 tumor suppressor gene in human epithelial ovarian carcinoma.

    Science.gov (United States)

    Kim, J W; Cho, Y H; Kwon, D J; Kim, T E; Park, T C; Lee, J M; Namkoong, S E

    1995-05-01

    Aberrations of the p53 gene in 26 surgical specimens of human epithelial ovarian carcinomas were examined by single-strand conformation polymorphism (SSCP) analysis of polymerase chain reaction (PCR) products. Seven (27%) of the tumors demonstrated a SSCP band shift in exons 4 to 9 of the gene, including 5 in the region encompassing exons 5 and 6, 1 in exon 7, and 1 in the region encompassing exons 8 and 9. Mutations were clustered in exon 5 in highly conserved regions of the p53 gene. All of the abnormal DNA fragments have been further characterized by direct DNA sequencing. These include five missense mutations (five transitions), a one-base-pair deletion introducing, by frameshift, a stop codon further downstream, and a two-base-pair insertion introducing a stop codon downstream by frameshift. Most mutations were base substitutions, and were clustered in exon 5 (71%), especially codons 175 and 179. The aberrations of the p53 gene were only found in tumors of FIGO stages III and IV. Histologic grading was also reviewed with respect to p53 aberrations. The aberrations were absent in well-differentiated carcinomas. The more undifferentiated the primary tumor, the more frequent p53 mutation (P p53 gene were common in epithelial ovarian cancers and p53 aberration may occur late during ovarian cancer evolution.

  11. Tumor suppressor gene E-cadherin and its role in normal and malignant cells

    Directory of Open Access Journals (Sweden)

    Pećina-Šlaus Nives

    2003-10-01

    Full Text Available Abstract E-cadherin tumor suppressor genes are particularly active area of research in development and tumorigenesis. The calcium-dependent interactions among E-cadherin molecules are critical for the formation and maintenance of adherent junctions in areas of epithelial cell-cell contact. Loss of E-cadherin-mediated-adhesion characterises the transition from benign lesions to invasive, metastatic cancer. Nevertheless, there is evidence that E-cadherins may also play a role in the wnt signal transduction pathway, together with other key molecules involved in it, such as beta-catenins and adenomatous poliposis coli gene products. The structure and function of E-cadherin, gene and protein, in normal as well as in tumor cells are reviewed in this paper.

  12. PLGA Nanoparticles for Ultrasound-Mediated Gene Delivery to Solid Tumors

    Directory of Open Access Journals (Sweden)

    Marxa Figueiredo

    2012-01-01

    Full Text Available This paper focuses on novel approaches in the field of nanotechnology-based carriers utilizing ultrasound stimuli as a means to spatially target gene delivery in vivo, using nanoparticles made with either poly(lactic-co-glycolic acid (PLGA or other polymers. We specifically discuss the potential for gene delivery by particles that are echogenic (amenable to destruction by ultrasound composed either of polymers (PLGA, polystyrene or other contrast agent materials (Optison, SonoVue microbubbles. The use of ultrasound is an efficient tool to further enhance gene delivery by PLGA or other echogenic particles in vivo. Echogenic PLGA nanoparticles are an attractive strategy for ultrasound-mediated gene delivery since this polymer is currently approved by the US Food and Drug Administration for drug delivery and diagnostics in cancer, cardiovascular disease, and also other applications such as vaccines and tissue engineering. This paper will review recent successes and the potential of applying PLGA nanoparticles for gene delivery, which include (a echogenic PLGA used with ultrasound to enhance local gene delivery in tumors or muscle and (b PLGA nanoparticles currently under development, which could benefit in the future from ultrasound-enhanced tumor targeted gene delivery.

  13. Ancestry as a potential modifier of gene expression in breast tumors from Colombian women.

    Science.gov (United States)

    Serrano-Gómez, Silvia J; Sanabria-Salas, María Carolina; Garay, Jone; Baddoo, Melody C; Hernández-Suarez, Gustavo; Mejía, Juan Carlos; García, Oscar; Miele, Lucio; Fejerman, Laura; Zabaleta, Jovanny

    2017-01-01

    Hispanic/Latino populations are a genetically admixed and heterogeneous group, with variable fractions of European, Indigenous American and African ancestries. The molecular profile of breast cancer has been widely described in non-Hispanic Whites but equivalent knowledge is lacking in Hispanic/Latinas. We have previously reported that the most prevalent breast cancer intrinsic subtype in Colombian women was Luminal B as defined by St. Gallen 2013 criteria. In this study we explored ancestry-associated differences in molecular profiles of Luminal B tumors among these highly admixed women. We performed whole-transcriptome RNA-seq analysis in 42 Luminal tumors (21 Luminal A and 21 Luminal B) from Colombian women. Genetic ancestry was estimated from a panel of 80 ancestry-informative markers (AIM). We categorized patients according to Luminal subtype and to the proportion of European and Indigenous American ancestry and performed differential expression analysis comparing Luminal B against Luminal A tumors according to the assigned ancestry groups. We found 5 genes potentially modulated by genetic ancestry: ERBB2 (log2FC = 2.367, padjancestry (p = 0.02, B = 3.11). This association was not biased by the distribution of HER2+ tumors among the groups analyzed. Our results suggest that genetic ancestry in Hispanic/Latina women might modify ERBB2 gene expression in Luminal tumors. Further analyses are needed to confirm these findings and explore their prognostic value.

  14. Oxygen Sensitivity of Reporter Genes: Implications for Preclinical Imaging of Tumor Hypoxia

    Directory of Open Access Journals (Sweden)

    Ivana Cecic

    2007-07-01

    Full Text Available Reporter gene techniques have been applied toward studying the physiologic phenomena associated with tumor hypoxia, a negative prognostic indicator. The purpose of this study was to assess the potential adverse effects of hypoxic conditions on the effectiveness of four commonly used reporter genes: Renilla luciferase, monomeric red fluorescent protein, thymidine kinase, and lacZ. Tumor-forming A375 cells expressing a trifusion reporter consisting of Renilla luciferase, monomeric red fluorescent protein, and thymidine kinase were subjected to decreasing oxygen tensions and assayed for reporter expression and activity. A375 cells expressing β-galactosidase were similarly exposed to hypoxia, with activity of the reporter monitored by cleavage of the fluorescent substrate 7-hydroxy-9H-(1, 3-dichloro-9, 9-dimethylacridin-2-one-β-galactoside (DDAOG. Generation of signal in in vivo tumor models expressing bioluminescent or β-galactosidase reporters were also examined over the course of hypoxic stresses, either by tumor clamping or the antivascular agent 5, 6-dimethylxanthenone-4-acetic acid (DMXAA. Our findings indicate that bioluminescent and fluorescent reporter activity are decreased under hypoxia despite minimal variations in protein production, whereas β-galactosidase reporter activity per unit protein was unchanged. These results demonstrate that combining β-galactosidase with the DDAOG optical probe may be a robust reporter system for the in vivo study of tumor hypoxia.

  15. Anti-tumor effects of gene therapy with GALV membrane fusion glycoprotein in lung adenocarcinoma.

    Science.gov (United States)

    Zhu, Bing; Yang, Jian-ru; Fu, Xin-ping; Jiang, Yue-quan

    2014-07-01

    This study examined the efficacy of gene therapy of lung adenocarcinoma using specifically controlled type I herpes simplex virus recombinant vector expressing Gibbon ape leukemia virus membrane fusion glycoprotein gene (GALV.fus). Recombinant HSV-I plasmid carrying target transgene was constructed, and recombinant viral vector was generated in Vero cells using Lipofectamine transfection. Viral vector was introduced into lung adenocarcinoma A549 cells or human fetal fibroblast HFL-I GNHu 5 cells, or inoculated into human lung adenocarcinoma xenografts in nude mice. The anti-tumor and cytotoxic effects of GALV-FMG, the transgene, were examined in these cell and animal models. Expression of GALV-FMG in xenographs achieved 100 % tumorigenicity. Recombinant HSV-I viral vector also exhibited significant tumor cell killing effect in vitro. Relative survival rates of tumor cells treated with GALV-FMG or control vectors were, respectively, 20 and 70 %. GALV.fus has a potent anti-tumor effect against lung cancer both in vitro and in vivo. This anti-tumor potential provides foundation for further studies with this vector.

  16. Tumor Classification Using High-Order Gene Expression Profiles Based on Multilinear ICA

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    Ming-gang Du

    2009-01-01

    Full Text Available Motivation. Independent Components Analysis (ICA maximizes the statistical independence of the representational components of a training gene expression profiles (GEP ensemble, but it cannot distinguish relations between the different factors, or different modes, and it is not available to high-order GEP Data Mining. In order to generalize ICA, we introduce Multilinear-ICA and apply it to tumor classification using high order GEP. Firstly, we introduce the basis conceptions and operations of tensor and recommend Support Vector Machine (SVM classifier and Multilinear-ICA. Secondly, the higher score genes of original high order GEP are selected by using t-statistics and tabulate tensors. Thirdly, the tensors are performed by Multilinear-ICA. Finally, the SVM is used to classify the tumor subtypes. Results. To show the validity of the proposed method, we apply it to tumor classification using high order GEP. Though we only use three datasets, the experimental results show that the method is effective and feasible. Through this survey, we hope to gain some insight into the problem of high order GEP tumor classification, in aid of further developing more effective tumor classification algorithms.

  17. Mutations in cancer genes of UV-induced skin tumors of hairless mice.

    Science.gov (United States)

    van Kranen, H J; de Gruijl, F R

    1999-12-01

    Ultraviolet (UV) radiation is a very common carcinogen in our environment. Epidemiological data on the relationship between skin cancers and ambient solar UV radiation are very limited. Hairless mice provide the possibility to study the process of UV carcinogenesis in more detail. Experiments with this animal model have yielded quantitative data on how tumor development depends on dose, time and wavelength of the UV radiation. In addition, at the molecular level the interactions between UV, specific cancer genes-like the Ras oncogene family and the p53 tumor suppressor gene, together with the role of DNA repair in this process have been addressed recently. In wildtype hairless mice mutations in the p53 gene are clearly linked to UVB but not to UVA radiation. Furthermore, the p53 alterations seem to be essential early in tumor development. However, in Xpa-deficient mice this dependency on p53 alterations appeared to be different as is the tumor type induced by UVB. Research using genetically modified hairless mice should enable us to further unravel the mechanisms of UV-induced skin cancer.

  18. An integrative CGH, MSI and candidate genes methylation analysis of colorectal tumors.

    Directory of Open Access Journals (Sweden)

    Hassan Brim

    Full Text Available Different DNA aberrations processes can cause colorectal cancer (CRC. Herein, we conducted a comprehensive molecular characterization of 27 CRCs from Iranian patients.Array CGH was performed. The MSI phenotype and the methylation status of 15 genes was established using MSP. The CGH data was compared to two established lists of 41 and 68 cancer genes, respectively, and to CGH data from African Americans. A maximum parsimony cladogram based on global aberrations was established.The number of aberrations seem to depend on the MSI status. MSI-H tumors displayed the lowest number of aberrations. MSP revealed that most markers were methylated, except RNF182 gene. P16 and MLH1 genes were primarily methylated in MSI-H tumors. Seven markers with moderate to high frequency of methylation (SYNE1, MMP2, CD109, EVL, RET, LGR and PTPRD had very low levels of chromosomal aberrations. All chromosomes were targeted by aberrations with deletions more frequent than amplifications. The most amplified markers were CD248, ERCC6, ERGIC3, GNAS, MMP2, NF1, P2RX7, SFRS6, SLC29A1 and TBX22. Most deletions were noted for ADAM29, CHL1, CSMD3, FBXW7, GALNS, MMP2, NF1, PRKD1, SMAD4 and TP53. Aberrations targeting chromosome X were primarily amplifications in male patients and deletions in female patients. A finding similar to what we reported for African American CRC patients.This first comprehensive analysis of CRC Iranian tumors reveals a high MSI rate. The MSI tumors displayed the lowest level of chromosomal aberrations but high frequency of methylation. The MSI-L were predominantly targeted with chromosomal instability in a way similar to the MSS tumors. The global chromosomal aberration profiles showed many similarities with other populations but also differences that might allow a better understanding of CRC's clinico-pathological specifics in this population.

  19. An integrative CGH, MSI and candidate genes methylation analysis of colorectal tumors.

    Science.gov (United States)

    Brim, Hassan; Abu-Asab, Mones S; Nouraie, Mehdi; Salazar, Jose; Deleo, Jim; Razjouyan, Hadi; Mokarram, Pooneh; Schaffer, Alejandro A; Naghibhossaini, Fakhraddin; Ashktorab, Hassan

    2014-01-01

    Different DNA aberrations processes can cause colorectal cancer (CRC). Herein, we conducted a comprehensive molecular characterization of 27 CRCs from Iranian patients. Array CGH was performed. The MSI phenotype and the methylation status of 15 genes was established using MSP. The CGH data was compared to two established lists of 41 and 68 cancer genes, respectively, and to CGH data from African Americans. A maximum parsimony cladogram based on global aberrations was established. The number of aberrations seem to depend on the MSI status. MSI-H tumors displayed the lowest number of aberrations. MSP revealed that most markers were methylated, except RNF182 gene. P16 and MLH1 genes were primarily methylated in MSI-H tumors. Seven markers with moderate to high frequency of methylation (SYNE1, MMP2, CD109, EVL, RET, LGR and PTPRD) had very low levels of chromosomal aberrations. All chromosomes were targeted by aberrations with deletions more frequent than amplifications. The most amplified markers were CD248, ERCC6, ERGIC3, GNAS, MMP2, NF1, P2RX7, SFRS6, SLC29A1 and TBX22. Most deletions were noted for ADAM29, CHL1, CSMD3, FBXW7, GALNS, MMP2, NF1, PRKD1, SMAD4 and TP53. Aberrations targeting chromosome X were primarily amplifications in male patients and deletions in female patients. A finding similar to what we reported for African American CRC patients. This first comprehensive analysis of CRC Iranian tumors reveals a high MSI rate. The MSI tumors displayed the lowest level of chromosomal aberrations but high frequency of methylation. The MSI-L were predominantly targeted with chromosomal instability in a way similar to the MSS tumors. The global chromosomal aberration profiles showed many similarities with other populations but also differences that might allow a better understanding of CRC's clinico-pathological specifics in this population.

  20. Tumor development is associated with decrease of TET gene expression and 5-methylcytosine hydroxylation

    OpenAIRE

    Yang, H; Liu, Y; Bai, F; Zhang, J-Y; Ma, S-H; Liu, J; Xu, Z-D; Zhu, H-G; Ling, Z-Q; Ye, D; Guan, K-L; Xiong, Y

    2012-01-01

    The TET (ten–eleven translocation) family of α-ketoglutarate (α-KG)-dependent dioxygenases catalyzes the sequential oxidation of 5-methylcytosine (5mC) to 5-hydroxymethyl-cytosine (5hmC), 5-formylcytosine and 5-carboxylcytosine, leading to eventual DNA demethylation. The TET2 gene is a bona fide tumor suppressor frequently mutated in leukemia, and TET enzyme activity is inhibited in IDH1/2-mutated tumors by the oncometabolite 2-hydroxyglutarate, an antagonist of α-KG, linking 5mC oxidation to...

  1. Candidate gene DNA methylation associations with breast cancer characteristics and tumor progression.

    Science.gov (United States)

    Kresovich, Jacob K; Gann, Peter H; Erdal, Serap; Chen, Hua Y; Argos, Maria; Rauscher, Garth H

    2018-03-12

    We examined methylation patterns with aggressive tumor phenotypes and investigated demographic, socioeconomic and reproductive predictors of gene methylation. Pyrosequencing quantified methylation of BRCA1, EGFR, GSTM2, RASSF1, TFF1 and Sat 2. We used quantile regression models to calculate adjusted median methylation values by estrogen and progesterone receptor (ER/PR) status. Bivariate associations between participant characteristics and methylation were examined. Higher percent methylation of GSTM2 was observed in ER/PR-negative compared with ER/PR-positive tumors in ductal carcinoma in situ (14 vs 2%) and invasive (35 vs 3%) tissue components. Trends in aberrant GSTM2 methylation across tissue components were stronger among ER/PR-negative tumors (p-interaction <0.001). Black women were more likely to have ER/PR-negative tumors (p = 0.01) and show hypermethylation of GSTM2 compared with other women (p = 0.05). GSTM2 promoter hypermethylation may serve as a potential biomarker of aggressive tumor development and a mechanism for ER/PR-negative tumor progression.

  2. confFuse: High-Confidence Fusion Gene Detection across Tumor Entities.

    Science.gov (United States)

    Huang, Zhiqin; Jones, David T W; Wu, Yonghe; Lichter, Peter; Zapatka, Marc

    2017-01-01

    Background: Fusion genes play an important role in the tumorigenesis of many cancers. Next-generation sequencing (NGS) technologies have been successfully applied in fusion gene detection for the last several years, and a number of NGS-based tools have been developed for identifying fusion genes during this period. Most fusion gene detection tools based on RNA-seq data report a large number of candidates (mostly false positives), making it hard to prioritize candidates for experimental validation and further analysis. Selection of reliable fusion genes for downstream analysis becomes very important in cancer research. We therefore developed confFuse, a scoring algorithm to reliably select high-confidence fusion genes which are likely to be biologically relevant. Results: confFuse takes multiple parameters into account in order to assign each fusion candidate a confidence score, of which score ≥8 indicates high-confidence fusion gene predictions. These parameters were manually curated based on our experience and on certain structural motifs of fusion genes. Compared with alternative tools, based on 96 published RNA-seq samples from different tumor entities, our method can significantly reduce the number of fusion candidates (301 high-confidence from 8,083 total predicted fusion genes) and keep high detection accuracy (recovery rate 85.7%). Validation of 18 novel, high-confidence fusions detected in three breast tumor samples resulted in a 100% validation rate. Conclusions: confFuse is a novel downstream filtering method that allows selection of highly reliable fusion gene candidates for further downstream analysis and experimental validations. confFuse is available at https://github.com/Zhiqin-HUANG/confFuse.

  3. Selector genes display tumor cooperation and inhibition in Drosophila epithelium in a developmental context-dependent manner

    OpenAIRE

    Ram Prakash Gupta; Anjali Bajpai; Pradip Sinha

    2017-01-01

    During animal development, selector genes determine identities of body segments and those of individual organs. Selector genes are also misexpressed in cancers, although their contributions to tumor progression per se remain poorly understood. Using a model of cooperative tumorigenesis, we show that gain of selector genes results in tumor cooperation, but in only select developmental domains of the wing, haltere and eye-antennal imaginal discs of Drosophila larva. Thus, the field selector, Ey...

  4. Selector genes display tumor cooperation and inhibition in Drosophila epithelium in a developmental context-dependent manner

    OpenAIRE

    Gupta, Ram Prakash; Bajpai, Anjali; Sinha, Pradip

    2017-01-01

    ABSTRACT During animal development, selector genes determine identities of body segments and those of individual organs. Selector genes are also misexpressed in cancers, although their contributions to tumor progression per se remain poorly understood. Using a model of cooperative tumorigenesis, we show that gain of selector genes results in tumor cooperation, but in only select developmental domains of the wing, haltere and eye-antennal imaginal discs of Drosophila larva. Thus, the field sel...

  5. Gene methylation profile of gastric cancerous tissue according to tumor site in the stomach.

    Science.gov (United States)

    Kupcinskaite-Noreikiene, Rita; Ugenskiene, Rasa; Noreika, Alius; Rudzianskas, Viktoras; Gedminaite, Jurgita; Skieceviciene, Jurgita; Juozaityte, Elona

    2016-01-26

    There is considerable information on the methylation of the promoter regions of different genes involved in gastric carcinogenesis. However, there is a lack of information on how this epigenetic process differs in tumors originating at different sites in the stomach. The aim of this study is to assess the methylation profiles of the MLH1, MGMT, and DAPK-1 genes in cancerous tissues from different stomach sites. Samples were acquired from 81 patients suffering stomach adenocarcinoma who underwent surgery for gastric cancer in the Lithuanian University of Health Sciences Hospital Kaunas Clinics in 2009-2012. Gene methylation was investigated with methylation-specific PCR. The study was approved by the Lithuanian Biomedical Research Ethics Committee. The frequencies of methylation in cancerous tissues from the upper, middle, and lower thirds of the stomach were 11.1, 23.1, and 45.4%, respectively, for MLH1; 22.2, 30.8, and 57.6%, respectively, for MGMT; and 44.4, 48.7, and 51.5%, respectively, for DAPK-1. MLH1 and MGMT methylation was observed more often in the lower third of the stomach than in the upper third (p stomach (coefficient, -0.48; p = 0.01). DAPK-1 and MLH1 methylation correlated inversely in tumors in the middle-third of the stomach (coefficient, -0.41; p = 0.01). Gene promoter methylation depends on the gastric tumor location.

  6. The Ras effector RASSF2 is a novel tumor-suppressor gene in human colorectal cancer.

    Science.gov (United States)

    Akino, Kimishige; Toyota, Minoru; Suzuki, Hiromu; Mita, Hiroaki; Sasaki, Yasushi; Ohe-Toyota, Mutsumi; Issa, Jean-Pierre J; Hinoda, Yuji; Imai, Kohzoh; Tokino, Takashi

    2005-07-01

    Activation of Ras signaling is a hallmark of colorectal cancer (CRC), but the roles of negative regulators of Ras are not fully understood. Our aim was to address that question by surveying genetic and epigenetic alterations of Ras-Ras effector genes in CRC cells. The expression and methylation status of 6 RASSF family genes were examined using RT-PCR and bisulfite PCR in CRC cell lines and in primary CRCs and colorectal adenomas. Colony formation assays and flow cytometry were used to assess the tumor suppressor activities of RASSF1 and RASSF2. Immunofluorescence microscopy was used to determine the effect of altered RASSF2 expression on cell morphology. Mutations of K- ras , BRAF, and p53 were identified using single-strand conformation analysis and direct sequencing. Aberrant methylation and histone deacetylation of RASSF2 was associated with the gene's silencing in CRC. The activities of RASSF2, which were distinct from those of RASSF1, included induction of morphologic changes and apoptosis; moreover, its ability to prevent cell transformation suggests that RASSF2 acts as a tumor suppressor in CRC. Primary CRCs that showed K- ras /BRAF mutations also frequently showed RASSF2 methylation, and inactivation of RASSF2 enhanced K- ras -induced oncogenic transformation. RASSF2 methylation was also frequently identified in colorectal adenomas. RASSF2 is a novel tumor suppressor gene that regulates Ras signaling and plays a pivotal role in the early stages of colorectal tumorigenesis.

  7. The tumor suppressor Rb and its related Rbl2 genes are regulated by Utx histone demethylase

    Energy Technology Data Exchange (ETDEWEB)

    Terashima, Minoru; Ishimura, Akihiko; Yoshida, Masakazu [Division of Functional Genomics, Cancer Research Institute, Kanazawa University, Kakuma-machi, Kanazawa 920-1192, Ishikawa (Japan); Suzuki, Yutaka; Sugano, Sumio [Graduate School of Frontier Sciences, The University of Tokyo, Kashiwa 277-8561, Chiba (Japan); Suzuki, Takeshi, E-mail: suzuki-t@staff.kanazawa-u.ac.jp [Division of Functional Genomics, Cancer Research Institute, Kanazawa University, Kakuma-machi, Kanazawa 920-1192, Ishikawa (Japan)

    2010-08-20

    Research highlights: {yields} Utx increases expression of Rb and Rbl2 genes through its demethylase activity. {yields} Utx changes histone H3 methylation on the Rb and Rbl2 promoters. {yields} Utx induces decreased cell proliferation of mammalian primary cells. -- Abstract: Utx is a candidate tumor suppressor gene that encodes histone H3 lysine 27 (H3K27) demethylase. In this study, we found that ectopic expression of Utx enhanced the expression of retinoblastoma tumor suppressor gene Rb and its related gene Rbl2. This activation was dependent on the demethylase activity of Utx, and was suggested to contribute to the decreased cell proliferation induced by Utx. A chromatin immunoprecipitation assay showed that over-expressed Utx was associated with the promoter regions of Rb and Rbl2 resulting in the removal of repressive H3K27 tri-methylation and the increase in active H3K4 tri-methylation. Furthermore, siRNA-mediated knockdown of Utx revealed the recruitment of endogenous Utx protein on the promoters of Rb and Rbl2 genes. These results indicate that Rb and Rbl2 are downstream target genes of Utx and may play important roles in Utx-mediated cell growth control.

  8. P53 tumor suppressor gene and protein expression is altered in cell lines derived from spontaneous and alpha-radiation-induced canine lung tumors

    International Nuclear Information System (INIS)

    Tierney, L.A.; Johnson, N.F.; Lechner, J.F.

    1994-01-01

    Mutations in the p53 tumor suppressor gene are the most frequently occurring gene alterations in malignant human cancers, including lung cancer. In lung cancer, common point mutations within conserved exons of the p53 gene result in a stabilized form of mutant protein which is detectable in most cases by immunohistochemistry. In addition to point mutations, allelic loss, rearrangements, and deletions of the p53 gene have also been detected in both human and rodent tumors. It has been suggested that for at least some epithelial neoplasms, the loss of expression of wild-type p53 protein may be more important for malignant transformation than the acquisition of activating mutations. Mechanisms responsible for the loss of expression of wild-type protein include gene deletion or rearrangement, nonsense or stop mutations, mutations within introns or upstream regulatory regions of the gene, and accelerated rates of degradation of the protein by DNA viral oncoproteins

  9. Filaggrin gene polymorphism associated with Epstein-Barr virus-associated tumors in China.

    Science.gov (United States)

    Yang, Yang; Liu, Wen; Zhao, Zhenzhen; Zhang, Yan; Xiao, Hua; Luo, Bing

    2017-08-01

    Mutations of filaggrin gene (FLG) have been identified as the cause of ichthyosis vulgaris, while recently FLG mutations were found to be associated with gastric cancer. This study aimed to investigate the association of filaggrin polymorphism with Epstein-Barr virus-associated tumors in China. A total of 200 patients with three types of tumors and 117 normal control samples were genotyped at three common FLG mutation loci (rs3126085, K4671X, R501X) by using Sequenom MassARRAY technique. The χ 2 test was used to evaluate the relationship between the mutation and the three kinds of tumors. A two-sided P value of Epstein-Barr virus (EBV)-associated gastric carcinoma (EBVaGC) and EBV-negative gastric carcinoma (EBVnGC), respectively. Furthermore, allele distributions in EBVaGC and EBVnGC were verified to be different in both SNP loci.

  10. ING Genes Work as Tumor Suppressor Genes in the Carcinogenesis of Head and Neck Squamous Cell Carcinoma

    Directory of Open Access Journals (Sweden)

    Xiaohan Li

    2011-01-01

    Full Text Available Head and neck squamous cell carcinoma (HNSCC is the sixth most common cancer in the world. The evolution and progression of HNSCC are considered to result from multiple stepwise alterations of cellular and molecular pathways in squamous epithelium. Recently, inhibitor of growth gene (ING family consisting of five genes, ING1 to ING5, was identified as a new tumor suppressor gene family that was implicated in the downregulation of cell cycle and chromatin remodeling. In contrast, it has been shown that ING1 and ING2 play an oncogenic role in some cancers, this situation being similar to TGF-β. In HNSCC, the ING family has been reported to be downregulated, and ING translocation from the nucleus to the cytoplasm may be a critical event for carcinogenesis. In this paper, we describe our recent results and briefly summarize current knowledge regarding the biologic functions of ING in HNSCC.

  11. Genetic and epigenetic silencing of the beclin 1 gene in sporadic breast tumors

    Directory of Open Access Journals (Sweden)

    Wu Yiqing

    2010-03-01

    Full Text Available Abstract Background Beclin 1, an important autophagy-related protein in human cells, is involved in cell death and cell survival. Beclin 1 mapped to human chromosome 17q21. It is widely expressed in normal mammary epithelial cells. Although down-regulated expression with mono-allelic deletions of beclin 1 gene was frequently observed in breast tumors, whether there was other regulatory mechanism of beclin 1 was to be investigated. We studied the expression of beclin 1 and explored the possible regulatory mechanisms on its expression in breast tumors. Methods 20 pairs of tumors and adjacent normal tissues from patients with sporadic breast invasive ductal cancer (IDCs were collected. The mRNA expression of beclin 1 was detected by real-time quantitative RT-PCR. Loss of heterozygosity (LOH was determined by real-time quantitative PCR and microsatellite methods. The protein expression of beclin 1, p53, BRCA1 and BRCA2 was assessed by immunohistochemistry. CpG islands in 5' genomic region of beclin 1 gene were identified using MethylPrimer Program. Sodium bisulfite sequencing was used in examining the methylation status of each CpG island. Results Decreased beclin 1 mRNA expression was detected in 70% of the breast tumors, and the protein levels were co-related to the mRNA levels. Expression of beclin 1 mRNA was demonstrated to be much higher in the BRCA1 positive tumors than that in the BRCA1 negative ones. Loss of heterozygosity was detected in more than 45% of the breast tumors, and a dense cluster of CpG islands was found from the 5' end to the intron 2 of the beclin 1 gene. Methylation analysis showed that the promoter and the intron 2 of beclin 1 were aberrantly methylated in the tumors with decreased expression. Conclusions These data indicated that LOH and aberrant DNA methylation might be the possible reasons of the decreased expression of beclin 1 in the breast tumors. The findings here shed some new light on the regulatory mechanisms of

  12. Genetic and epigenetic silencing of the beclin 1 gene in sporadic breast tumors

    International Nuclear Information System (INIS)

    Li, Zidong; Chen, Bo; Wu, Yiqing; Jin, Feng; Xia, Yongjing; Liu, Xiangjun

    2010-01-01

    Beclin 1, an important autophagy-related protein in human cells, is involved in cell death and cell survival. Beclin 1 mapped to human chromosome 17q21. It is widely expressed in normal mammary epithelial cells. Although down-regulated expression with mono-allelic deletions of beclin 1 gene was frequently observed in breast tumors, whether there was other regulatory mechanism of beclin 1 was to be investigated. We studied the expression of beclin 1 and explored the possible regulatory mechanisms on its expression in breast tumors. 20 pairs of tumors and adjacent normal tissues from patients with sporadic breast invasive ductal cancer (IDCs) were collected. The mRNA expression of beclin 1 was detected by real-time quantitative RT-PCR. Loss of heterozygosity (LOH) was determined by real-time quantitative PCR and microsatellite methods. The protein expression of beclin 1, p53, BRCA1 and BRCA2 was assessed by immunohistochemistry. CpG islands in 5' genomic region of beclin 1 gene were identified using MethylPrimer Program. Sodium bisulfite sequencing was used in examining the methylation status of each CpG island. Decreased beclin 1 mRNA expression was detected in 70% of the breast tumors, and the protein levels were co-related to the mRNA levels. Expression of beclin 1 mRNA was demonstrated to be much higher in the BRCA1 positive tumors than that in the BRCA1 negative ones. Loss of heterozygosity was detected in more than 45% of the breast tumors, and a dense cluster of CpG islands was found from the 5' end to the intron 2 of the beclin 1 gene. Methylation analysis showed that the promoter and the intron 2 of beclin 1 were aberrantly methylated in the tumors with decreased expression. These data indicated that LOH and aberrant DNA methylation might be the possible reasons of the decreased expression of beclin 1 in the breast tumors. The findings here shed some new light on the regulatory mechanisms of beclin 1 in breast cancer

  13. Predicting survival in patients with metastatic kidney cancer by gene-expression profiling in the primary tumor.

    Science.gov (United States)

    Vasselli, James R; Shih, Joanna H; Iyengar, Shuba R; Maranchie, Jodi; Riss, Joseph; Worrell, Robert; Torres-Cabala, Carlos; Tabios, Ray; Mariotti, Andra; Stearman, Robert; Merino, Maria; Walther, McClellan M; Simon, Richard; Klausner, Richard D; Linehan, W Marston

    2003-06-10

    To identify potential molecular determinants of tumor biology and possible clinical outcomes, global gene-expression patterns were analyzed in the primary tumors of patients with metastatic renal cell cancer by using cDNA microarrays. We used grossly dissected tumor masses that included tumor, blood vessels, connective tissue, and infiltrating immune cells to obtain a gene-expression "profile" from each primary tumor. Two patterns of gene expression were found within this uniformly staged patient population, which correlated with a significant difference in overall survival between the two patient groups. Subsets of genes most significantly associated with survival were defined, and vascular cell adhesion molecule-1 (VCAM-1) was the gene most predictive for survival. Therefore, despite the complex biological nature of metastatic cancer, basic clinical behavior as defined by survival may be determined by the gene-expression patterns expressed within the compilation of primary gross tumor cells. We conclude that survival in patients with metastatic renal cell cancer can be correlated with the expression of various genes based solely on the expression profile in the primary kidney tumor.

  14. Gene profiling and circulating tumor cells as biomarker to prognostic of patients with locoregional breast cancer.

    Science.gov (United States)

    Kuniyoshi, Renata K; Gehrke, Flávia de Sousa; Alves, Beatriz C A; Vilas-Bôas, Viviane; Coló, Anna E; Sousa, Naiara; Nunes, João; Fonseca, Fernando L A; Del Giglio, Auro

    2015-09-01

    The gene profile of primary tumors, as well as the identification of circulating tumor cells (CTCs), can provide important prognostic and predictive information. In this study, our objective was to perform tumor gene profiling (TGP) in combination with CTC characterization in women with nonmetastatic breast cancer. Biological samples (from peripheral blood and tumors) from 167 patients diagnosed with stage I, II, and III mammary carcinoma, who were also referred for adjuvant/neoadjuvant chemotherapy, were assessed for the following parameters: (a) the presence of CTCs identified by the expression of CK-19 and c-erbB-2 in the peripheral blood mononuclear cell (PBMC) fraction by quantitative reverse transcription PCR (RT-PCR) and (b) the TGP, which was determined by analyzing the expression of 21 genes in paraffin-embedded tissue samples by quantitative multiplex RT-PCR with the Plexor® system. We observed a statistically significant correlation between the progression-free interval (PFI) and the clinical stage (p = 0.000701), the TGP score (p = 0.006538), and the presence of hormone receptors in the tumor (p = 0.0432). We observed no correlation between the PFI and the presence or absence of CK-19 or HER2 expression in the PBMC fraction prior to the start of treatment or in the two following readouts. Multivariate analysis revealed that only the TGP score significantly correlated with the PFI (p = 0.029247). The TGP is an important prognostic variable for patients with locoregional breast cancer. The presence of CTCs adds no prognostic value to the information already provided by the TGP.

  15. Positional cloning of genes involved in the Beckwith-Wiedemann syndrome, hemihypertrophy, and associated childhood tumors.

    Science.gov (United States)

    Mannens, M; Alders, M; Redeker, B; Bliek, J; Steenman, M; Wiesmeyer, C; de Meulemeester, M; Ryan, A; Kalikin, L; Voûte, T; De Kraker, J; Hoovers, J; Slater, R; Feinberg, A; Little, P; Westerveld, A

    1996-11-01

    The Beckwith-Wiedemann syndrome (BWS) is an overgrowth malformation syndrome that occurs with an incidence of 1:13,700 births. There is a striking incidence of childhood tumors found in BWS patients. Various lines of investigation have localized "imprinted" genes involved in BWS and associated childhood tumors to 11p15. High resolution mapping of 8 rare balanced chromosomal BWS rearrangements enabled us to identify three distinct regions on chromosome 11p15 that might harbor genes involved in the above-mentioned disorders. These results suggest genetic heterogeneity that correlates with the clinical heterogeneity seen in the patients studied. Expressed candidate gene sequences from these regions have been cloned and partly sequenced. These transcripts are either disrupted by or are at least within a few kb of these BWS chromosome breakpoints. So far, zinc-finger sequences and one Kruppel-associated box (KRAB) domain were found in independent candidate genes which are compatible with a regulating function of growth promoting genes. The abundance of expression of these genes varies from low abundant in all adult and fetal tissues tested to detectable on Northern blots of adult tissues. In addition to our 11p15 studies we have analyzed additional chromosome regions, in particular 1p. Cytogenetic, loss of heterozygosity (LOH) and comparative genomic hybridization (CGH) studies have identified 1p35 as a region of interest. A positional cloning effort to identify a balanced 1p35 translocation found in a Wilms tumor has led to the isolation of a YAC, crossing this breakpoint.

  16. Implication of p53-dependent cellular senescence related gene, TARSH in tumor suppression

    International Nuclear Information System (INIS)

    Wakoh, Takeshi; Uekawa, Natsuko; Terauchi, Kunihiko; Sugimoto, Masataka; Ishigami, Akihito; Shimada, Jun-ichi; Maruyama, Mitsuo

    2009-01-01

    A novel target of NESH-SH3 (TARSH) was identified as a cellular senescence related gene in mouse embryonic fibroblasts (MEFs) replicative senescence, the expression of which has been suppressed in primary clinical lung cancer specimens. However, the molecular mechanism underlying the regulation of TARSH involved in pulmonary tumorigenesis remains unclear. Here we demonstrate that the reduction of TARSH gene expression by short hairpin RNA (shRNA) system robustly inhibited the MEFs proliferation with increase in senescence-associated β-galactosidase (SA-β-gal) activity. Using p53 -/- MEFs, we further suggest that this growth arrest by loss of TARSH is evoked by p53-dependent p21 Cip1 accumulation. Moreover, we also reveal that TARSH reduction induces multicentrosome in MEFs, which is linked in chromosome instability and tumor development. These results suggest that TARSH plays an important role in proliferation of replicative senescence and may serve as a trigger of tumor development.

  17. gld-1, a tumor suppressor gene required for oocyte development in Caenorhabditis elegans

    Energy Technology Data Exchange (ETDEWEB)

    Francis, R.; Schedl, T. [Washington Univ. School of Medicine, St. Louis, MO (United States); Barton, M.K.; Kimble, J. [Univ. of Wisconsin, Madison, WI (United States)

    1995-02-01

    We have characterized 31 mutations in the gld-1 (defective in germline development) gene of Caenorhabditis elegans. In gld-1 (null) hermaphrodites, oogenesis is abolished and a germline tumor forms where oocyte development would normally occur. By contrast, gld-1 (null) males are unaffected. The hermaphrodite germline tumor appears to derive from germ cells that enter the meiotic pathway normally but then exit pachytene and return to the mitotic cycle. Certain gld-1 partial loss-of-function mutations also abolish oogenesis, but germ cells arrest in pachytene rather than returning to mitosis. Our results indicate that gld-1 is a tumor suppressor gene required for oocyte development. The tumorous phenotype suggests that gld-1(+) may function to negatively regulate proliferation during meiotic prophase and/or act to direct progression through meiotic prophase. We also show that gld-1(+) has an additional nonessential role in germline sex determination: promotion of hermaphrodite spermatogenesis. This function of gld-1 is inferred from a haplo-insufficient phenotype and from the properties of gain-of-function gld-1 mutations that cause alterations in the sexual identity of germ cells. 69 refs., 10 figs., 8 tabs.

  18. Mice lacking pituitary tumor transforming gene show elevated exposure of DGalNAc carbohydrate determinants

    Directory of Open Access Journals (Sweden)

    Lutsyk A. D.

    2012-04-01

    Full Text Available Aim. To investigate the influence of pituitary tumor transforming gene (pttg-1 knockout on glycome of parenchimal organs by means of lectin histochemistry. Methods. DGalNAc, DGlcNAc, NeuNAc carbohydrate determinants were labelled with soybean agglutinin (SBA and wheat germ agglutinin (WGA, conjugated to peroxidase, with subsequent visualization of the lectin-binding sites with diaminobenzidine. The testes and kidneys of murine strain BL6/C57 with the pttg-1 gene knockout (PTTG-KO were compared to the wild type (PTTG-WT animals, both groups 1 month of age. Results. Knockout of the pttg-1 gene was accompanied by enhanced exposure of the DGalNAc sugar residues within the Golgi complex of secondary spermatocytes, in a brush border of renal tubules and on the lumenal surface of collecting ducts. Conclusions. This study suggests that knockout of the pttg-1 gene may lead to the changes in carbohydrate processing in mammalian organism.

  19. Mechanisms of epigenetic silencing of the c21 gene in Y1 adrenocortical tumor cells.

    Science.gov (United States)

    Szyf, M; Slack, A D

    2000-11-01

    We utilized Y1 adrenocortical carcinoma cell line as a model system to dissect the events regulating epigenomic gene silencing in tumor cells. We show here that the chromatin structure of c21 gene is inactive in Y1 cells and that it could be reconfigured to an active form by either expressing antisense mRNA to DNA methyltransferase 1 (dnmt1) or an attenuator of Ras protooncogenic signaling hGAP. Surprisingly however, the known inducer of active chromatin structure the histone deacetylase inhibitor trichostatin A TSA fails to induce expression of c21. These results suggest that the primary cause of c21 gene silencing is independent of histone deacetylation. We present a model to explain the possible roles of the different components of the epigenome and the DNA methylation and demethylation machineries in silencing c21 gene expression.

  20. A targeted constitutive mutation in the APC tumor suppressor gene underlies mammary but not intestinal tumorigenesis.

    Directory of Open Access Journals (Sweden)

    Claudia Gaspar

    2009-07-01

    Full Text Available Germline mutations in the adenomatous polyposis coli (APC gene are responsible for familial adenomatous polyposis (FAP, an autosomal dominant hereditary predisposition to the development of multiple colorectal adenomas and of a broad spectrum of extra-intestinal tumors. Moreover, somatic APC mutations play a rate-limiting and initiating role in the majority of sporadic colorectal cancers. Notwithstanding its multifunctional nature, the main tumor suppressing activity of the APC gene resides in its ability to regulate Wnt/beta-catenin signaling. Notably, genotype-phenotype correlations have been established at the APC gene between the length and stability of the truncated proteins encoded by different mutant alleles, the corresponding levels of Wnt/beta-catenin signaling activity they encode for, and the incidence and distribution of intestinal and extra-intestinal tumors. Here, we report a novel mouse model, Apc1572T, obtained by targeting a truncated mutation at codon 1572 in the endogenous Apc gene. This hypomorphic mutant allele results in intermediate levels of Wnt/beta-catenin signaling activation when compared with other Apc mutations associated with multifocal intestinal tumors. Notwithstanding the constitutive nature of the mutation, Apc(+/1572T mice have no predisposition to intestinal cancer but develop multifocal mammary adenocarcinomas and subsequent pulmonary metastases in both genders. The histology of the Apc1572T primary mammary tumours is highly heterogeneous with luminal, myoepithelial, and squamous lineages and is reminiscent of metaplastic carcinoma of the breast in humans. The striking phenotype of Apc(+/1572T mice suggests that specific dosages of Wnt/beta-catenin signaling activity differentially affect tissue homeostasis and initiate tumorigenesis in an organ-specific fashion.

  1. Histamine suppresses gene expression and synthesis of tumor necrosis factor alpha via histamine H2 receptors

    OpenAIRE

    1991-01-01

    Histamine and tumor necrosis factor alpha (TNF-alpha) can each contribute to the pathogenesis of allergic reactions and chronic inflammatory diseases. We now report the effect of histamine on gene expression and total cellular synthesis of TNF-alpha. Lipopolysaccharide (LPS)-induced synthesis of TNF-alpha in peripheral blood mononuclear cells (PBMC) from 18 healthy donors was suppressed by histamine concentrations from 10(-6) to 10(-4) M, levels comparable with those measured in tissues after...

  2. Mesenchymal Stem Cell-Based Tumor-Targeted Gene Therapy in Gastrointestinal Cancer

    OpenAIRE

    Bao, Qi; Zhao, Yue; Niess, Hanno; Conrad, Claudius; Schwarz, Bettina; Jauch, Karl-Walter; Huss, Ralf; Nelson, Peter J.; Bruns, Christiane J.

    2012-01-01

    Mesenchymal stem (or stromal) cells (MSCs) are nonhematopoietic progenitor cells that can be obtained from bone marrow aspirates or adipose tissue, expanded and genetically modified in vitro, and then used for cancer therapeutic strategies in vivo. Here, we review available data regarding the application of MSC-based tumor-targeted therapy in gastrointestinal cancer, provide an overview of the general history of MSC-based gene therapy in cancer research, and discuss potential problems associa...

  3. Generation of two modified mouse alleles of the Hic1 tumor suppressor gene

    Czech Academy of Sciences Publication Activity Database

    Pospíchalová, Vendula; Turečková, Jolana; Fafílek, Bohumil; Vojtěchová, Martina; Krausová, Michaela; Lukáš, Jan; Šloncová, Eva; Takacova, S.; Divoký, V.; Leprince, D.; Plachý, Jiří; Kořínek, Vladimír

    2011-01-01

    Roč. 49, č. 3 (2011), s. 142-151 ISSN 1526-954X R&D Projects: GA ČR(CZ) GA204/07/1567; GA ČR(CZ) GD204/09/H058 Institutional research plan: CEZ:AV0Z50520514 Keywords : Hypermethylated In Cancer 1 * Hic1 tumor suppressor * gene targeting Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 2.527, year: 2011

  4. Tumor grade-related NDRG2 gene expression in primary and recurrent intracranial meningiomas.

    Science.gov (United States)

    Skiriute, Daina; Tamasauskas, Sarunas; Asmoniene, Virginija; Saferis, Viktoras; Skauminas, Kestutis; Deltuva, Vytenis; Tamasauskas, Arimantas

    2011-03-01

    Approximately 30% of all primary CNS tumors are meningiomas. Depending on histological type, meningiomas can recur as follows: benign--with five-year recurrence of 5%, atypical--recurrence approximately 40%, and anaplastic with recurrence of 50-80%. In an attempt to understand the molecular mechanism of meningioma recurrence we investigated the N-Myc downstream-regulated gene 2 (NDRG2), which has recently been described as important in suppressing cellular carcinogenesis in different types of cancer. The objective of the study was to investigate NDRG2 gene expression at the mRNA level in primary and recurrent meningiomas as a potential marker of tumor aggressiveness, malignancy, and recurrence. Primary and recurrent meningiomas of WHO grades I, II, and III from 35 patients operated on between 2005 and 2008 year at the Department of Neurosurgery of Kaunas Medical University Hospital (Lithuania) were studied. Using the qRT-PCR method we measured NDRG2 gene expression at the mRNA level in primary (n = 24) and recurrent (n = 11) meningiomas. Statistically significant differences in NDRG2 gene expression level were observed between primary and recurrent meningioma groups (P grade I) and atypical (WHO grade II) meningiomas (P 0.05) among histological subtypes of benign (WHO grade I) meningiomas: fibrous, meningothelial, and transitional. In accordance with our results, reduction of NDRG2 gene expression at the mRNA level could help to explain malignant progression and predisposition to recurrence in meningiomas.

  5. Distinct and competitive regulatory patterns of tumor suppressor genes and oncogenes in ovarian cancer.

    Directory of Open Access Journals (Sweden)

    Min Zhao

    Full Text Available So far, investigators have found numerous tumor suppressor genes (TSGs and oncogenes (OCGs that control cell proliferation and apoptosis during cancer development. Furthermore, TSGs and OCGs may act as modulators of transcription factors (TFs to influence gene regulation. A comprehensive investigation of TSGs, OCGs, TFs, and their joint target genes at the network level may provide a deeper understanding of the post-translational modulation of TSGs and OCGs to TF gene regulation.In this study, we developed a novel computational framework for identifying target genes of TSGs and OCGs using TFs as bridges through the integration of protein-protein interactions and gene expression data. We applied this pipeline to ovarian cancer and constructed a three-layer regulatory network. In the network, the top layer was comprised of modulators (TSGs and OCGs, the middle layer included TFs, and the bottom layer contained target genes. Based on regulatory relationships in the network, we compiled TSG and OCG profiles and performed clustering analyses. Interestingly, we found TSGs and OCGs formed two distinct branches. The genes in the TSG branch were significantly enriched in DNA damage and repair, regulating macromolecule metabolism, cell cycle and apoptosis, while the genes in the OCG branch were significantly enriched in the ErbB signaling pathway. Remarkably, their specific targets showed a reversed functional enrichment in terms of apoptosis and the ErbB signaling pathway: the target genes regulated by OCGs only were enriched in anti-apoptosis and the target genes regulated by TSGs only were enriched in the ErbB signaling pathway.This study provides the first comprehensive investigation of the interplay of TSGs and OCGs in a regulatory network modulated by TFs. Our application in ovarian cancer revealed distinct regulatory patterns of TSGs and OCGs, suggesting a competitive regulatory mechanism acting upon apoptosis and the ErbB signaling pathway through

  6. Bilateral renal tumors in an adult man with Smith-Magenis syndrome: The role of the FLCN gene.

    Science.gov (United States)

    Dardour, Leila; Verleyen, Pieter; Lesage, Karl; Holvoet, Maureen; Devriendt, Koen

    2016-10-01

    Smith-Magenis syndrome (SMS) is a contiguous-gene disorder most commonly caused by a deletion of chromosome 17p11.2. We report a 57 year-old man with SMS who presents bilateral renal tumors. This is most likely related to haploinsufficiency of FLCN gene, located in the deleted region, and a known tumor suppressor gene. Haploinsufficiency of FLCN causes Birt-Hogg-Dubé syndrome (BHDS), characterized by pulmonary cysts, renal and skin tumors. The present observation suggests that the follow-up of patients with SMS should also focus on possible manifestations of BHDS. Copyright © 2016 Elsevier Masson SAS. All rights reserved.

  7. Combined anti-tumor therapeutic effect of targeted gene, hyperthermia, radionuclide brachytherapy in breast carcinoma

    International Nuclear Information System (INIS)

    Chen Daozhen; Tang Qiusha; Xiang Jingying; Xu Fei; Zhang Li; Wang Junfeng

    2011-01-01

    Objective: To investigate the antitumor therapeutic effect of combined therapy of magnetic induction heating by nano-magnetic particles, herpes simplex virus thymidine kinase gene (HSV-tk suicide gene) and internal radiation in mice bearing MCF-7 breast carcinoma. Methods: The transfection reagents, plasmids heat shock protein-HSV-tk (pHSP-HSV-tk), ferroso-ferric oxide nano-magnetic fluid flow and 188 Re-ganciclovir-bovine serum albumin-nanopaticles (GCV-BSA-NP) were prepared. The heating experiments in vivo were carried out using ferroso-ferric oxide nano-magnetic fluid flow. Sixty mice tumor models bearing MCF-7 breast carcinoma were established and randomly divided into six groups. Group A was the control group, B was gene transfection therapy group, C was hyperthermia group, D was gene transfection therapy combined with radionuclide brachytherapy group, E was gene therapy combined with hyperthermia group, and F was gene therapy, hyperthermia combined with radionuclide brachytherapy group. The tumor growth, tumor mass and histopathological changes were evaluated. The expression of HSV-tk in the groups of B, D, E and F was detected by RT-PCR. Poisson distribution and one-way analysis of variance (ANOVA) were used for statistical analysis by SPSS 10.0 software. Results: In the animal heating experiments, the temperature of tumor increased up to 39.6 degree C, 43.2 degree C, and 48.1 degree C quickly with different injected doses (2, 4 and 6 mg respectively) of nano-magnetic particles and maintained for 40 min. The temperature of tumor tissue reduced to 36.8 degree C, 37.5 degree C and 37.8 degree C in 10 min when alternating magnetic field (AMF) stopped. The tumor mass in Groups C ((452.50±30.29) mg), D ((240.98±35.32)mg), E((231.87±27.41) mg) and F ((141.55±23.78) mg) were much lower than that in Group A ((719.12±22.65) mg) (F=800.07, P<0.01), with the most significant treatment effect in Group F.The tumor mass in Group B((684.05±24.02) mg) was higher than

  8. A molecular analysis by gene expression profiling reveals Bik/NBK overexpression in sporadic breast tumor samples of Mexican females

    International Nuclear Information System (INIS)

    García, Normand; Salamanca, Fabio; Astudillo-de la Vega, Horacio; Curiel-Quesada, Everardo; Alvarado, Isabel; Peñaloza, Rosenda; Arenas, Diego

    2005-01-01

    Breast cancer is one of the most frequent causes of death in Mexican women over 35 years of age. At molecular level, changes in many genetic networks have been reported as associated with this neoplasia. To analyze these changes, we determined gene expression profiles of tumors from Mexican women with breast cancer at different stages and compared these with those of normal breast tissue samples. 32 P-radiolabeled cDNA was synthesized by reverse transcription of mRNA from fresh sporadic breast tumor biopsies, as well as normal breast tissue. cDNA probes were hybridized to microarrays and expression levels registered using a phosphorimager. Expression levels of some genes were validated by real time RT-PCR and immunohistochemical assays. We identified two subgroups of tumors according to their expression profiles, probably related with cancer progression. Ten genes, unexpressed in normal tissue, were turned on in some tumors. We found consistent high expression of Bik gene in 14/15 tumors with predominant cytoplasmic distribution. Recently, the product of the Bik gene has been associated with tumoral reversion in different neoplasic cell lines, and was proposed as therapy to induce apoptosis in cancers, including breast tumors. Even though a relationship among genes, for example those from a particular pathway, can be observed through microarrays, this relationship might not be sufficient to assign a definitive role to Bik in development and progression of the neoplasia. The findings herein reported deserve further investigation

  9. Quantitative gene-expression of the tumor angiogenesis markers vascular endothelial growth factor, integrin alphaV and integrin beta3 in human neuroendocrine tumors

    DEFF Research Database (Denmark)

    Oxboel, Jytte; Binderup, Tina; Knigge, Ulrich

    2009-01-01

    Anti-angiogenesis treatment is a promising new therapy for cancer that recently has also been suggested for patients with neuroendocrine tumors. The aim of the present study was therefore to investigate the level of tumor angiogenesis, and thereby the molecular basis for anti-angiogenesis treatment......, in neuroendocrine tumors. We used quantitative real-time PCR for measuring mRNA gene-expression of vascular endothelial growth factor (VEGF), integrin alphaV, and integrin beta3, and CD34 for a group of patients with neuroendocrine tumors (n=13). Tissue from patients with colorectal cancer liver metastases (n=14......) and normal liver tissues (n=16) was used as control. We found a lower mRNA level of VEGF in neuroendocrine tumors compared to both colorectal liver metastases (ptumors...

  10. T cells stimulate catabolic gene expression by the stromal cells from giant cell tumor of bone

    Energy Technology Data Exchange (ETDEWEB)

    Cowan, Robert W. [Department of Pathology and Molecular Medicine, McMaster University, 1280 Main St. W., Hamilton, ON, Canada L8S 4L8 (Canada); Juravinski Cancer Centre, 699 Concession St., Hamilton, ON, Canada L8V 5C2 (Canada); Ghert, Michelle [Juravinski Cancer Centre, 699 Concession St., Hamilton, ON, Canada L8V 5C2 (Canada); Department of Surgery, McMaster University, 1280 Main St. W., Hamilton, ON, Canada L8S 4L8 (Canada); Singh, Gurmit, E-mail: gurmit.singh@jcc.hhsc.ca [Department of Pathology and Molecular Medicine, McMaster University, 1280 Main St. W., Hamilton, ON, Canada L8S 4L8 (Canada); Juravinski Cancer Centre, 699 Concession St., Hamilton, ON, Canada L8V 5C2 (Canada)

    2012-03-23

    Highlights: Black-Right-Pointing-Pointer Two T cell lines stimulate PTHrP, RANKL, MMP13 gene expression in GCT cell cultures. Black-Right-Pointing-Pointer CD40 expressed by stromal cells; CD40L detected in whole tumor but not cultures. Black-Right-Pointing-Pointer Effect of CD40L treatment on GCT cells increased PTHrP and MMP13 gene expression. Black-Right-Pointing-Pointer PTHrP treatment increased MMP13 expression, while inhibition decreased expression. Black-Right-Pointing-Pointer T cells may stimulate GCT stromal cells and promote the osteolysis of the tumor. -- Abstract: The factors that promote the localized bone resorption by giant cell tumor of bone (GCT) are not fully understood. We investigated whether T cells could contribute to bone resorption by stimulating expression of genes for parathyroid hormone-related protein (PTHrP), matrix metalloproteinase (MMP)-13, and the receptor activator of nuclear-factor {kappa}B ligand (RANKL). Two cell lines, Jurkat clone E6-1 and D1.1, were co-cultured with isolated GCT stromal cells. Real-time PCR analyses demonstrated a significant increase of all three genes following 48 h incubation, and PTHrP and MMP-13 gene expression was also increased at 24 h. Further, we examined the expression of CD40 ligand (CD40L), a protein expressed by activated T cells, and its receptor, CD40, in GCT. Immunohistochemistry results revealed expression of the CD40 receptor in both the stromal cells and giant cells of the tumor. RNA collected from whole GCT tissues showed expression of CD40LG, which was absent in cultured stromal cells, and suggests that CD40L is expressed within GCT. Stimulation of GCT stromal cells with CD40L significantly increased expression of the PTHrP and MMP-13 genes. Moreover, we show that inhibition of PTHrP with neutralizing antibodies significantly decreased MMP13 expression by the stromal cells compared to IgG-matched controls, whereas stimulation with PTHrP (1-34) increased MMP-13 gene expression. These

  11. Classification between normal and tumor tissues based on the pair-wise gene expression ratio

    International Nuclear Information System (INIS)

    Yap, YeeLeng; Zhang, XueWu; Ling, MT; Wang, XiangHong; Wong, YC; Danchin, Antoine

    2004-01-01

    Precise classification of cancer types is critically important for early cancer diagnosis and treatment. Numerous efforts have been made to use gene expression profiles to improve precision of tumor classification. However, reliable cancer-related signals are generally lacking. Using recent datasets on colon and prostate cancer, a data transformation procedure from single gene expression to pair-wise gene expression ratio is proposed. Making use of the internal consistency of each expression profiling dataset this transformation improves the signal to noise ratio of the dataset and uncovers new relevant cancer-related signals (features). The efficiency in using the transformed dataset to perform normal/tumor classification was investigated using feature partitioning with informative features (gene annotation) as discriminating axes (single gene expression or pair-wise gene expression ratio). Classification results were compared to the original datasets for up to 10-feature model classifiers. 82 and 262 genes that have high correlation to tissue phenotype were selected from the colon and prostate datasets respectively. Remarkably, data transformation of the highly noisy expression data successfully led to lower the coefficient of variation (CV) for the within-class samples as well as improved the correlation with tissue phenotypes. The transformed dataset exhibited lower CV when compared to that of single gene expression. In the colon cancer set, the minimum CV decreased from 45.3% to 16.5%. In prostate cancer, comparable CV was achieved with and without transformation. This improvement in CV, coupled with the improved correlation between the pair-wise gene expression ratio and tissue phenotypes, yielded higher classification efficiency, especially with the colon dataset – from 87.1% to 93.5%. Over 90% of the top ten discriminating axes in both datasets showed significant improvement after data transformation. The high classification efficiency achieved suggested

  12. Frequent loss of heterozygosity and altered expression of the candidate tumor suppressor gene 'FAT' in human astrocytic tumors

    International Nuclear Information System (INIS)

    Chosdol, Kunzang; Misra, Anjan; Puri, Sachin; Srivastava, Tapasya; Chattopadhyay, Parthaprasad; Sarkar, Chitra; Mahapatra, Ashok K; Sinha, Subrata

    2009-01-01

    We had earlier used the comparison of RAPD (Random Amplification of Polymorphic DNA) DNA fingerprinting profiles of tumor and corresponding normal DNA to identify genetic alterations in primary human glial tumors. This has the advantage that DNA fingerprinting identifies the genetic alterations in a manner not biased for locus. In this study we used RAPD-PCR to identify novel genomic alterations in the astrocytic tumors of WHO grade II (Low Grade Diffuse Astrocytoma) and WHO Grade IV (Glioblastoma Multiforme). Loss of heterozygosity (LOH) of the altered region was studied by microsatellite and Single Nucleotide Polymorphism (SNP) markers. Expression study of the gene identified at the altered locus was done by semi-quantitative reverse-transcriptase-PCR (RT-PCR). Bands consistently altered in the RAPD profile of tumor DNA in a significant proportion of tumors were identified. One such 500 bp band, that was absent in the RAPD profile of 33% (4/12) of the grade II astrocytic tumors, was selected for further study. Its sequence corresponded with a region of FAT, a putative tumor suppressor gene initially identified in Drosophila. Fifty percent of a set of 40 tumors, both grade II and IV, were shown to have Loss of Heterozygosity (LOH) at this locus by microsatellite (intragenic) and by SNP markers. Semi-quantitative RT-PCR showed low FAT mRNA levels in a major subset of tumors. These results point to a role of the FAT in astrocytic tumorigenesis and demonstrate the use of RAPD analysis in identifying specific alterations in astrocytic tumors

  13. Glucose Metabolism Gene Expression Patterns and Tumor Uptake of 18F-Fluorodeoxyglucose After Radiation Treatment

    International Nuclear Information System (INIS)

    Wilson, George D.; Thibodeau, Bryan J.; Fortier, Laura E.; Pruetz, Barbara L.; Galoforo, Sandra; Baschnagel, Andrew M.; Chunta, John; Oliver Wong, Ching Yee; Yan, Di; Marples, Brian; Huang, Jiayi

    2014-01-01

    Purpose: To investigate whether radiation treatment influences the expression of glucose metabolism genes and compromises the potential use of 18 F-fluorodeoxyglucose positron emission tomography (FDG-PET) as a tool to monitor the early response of head and neck cancer xenografts to radiation therapy (RT). Methods and Materials: Low passage head and neck squamous cancer cells (UT14) were injected to the flanks of female nu/nu mice to generate xenografts. After tumors reached a size of 500 mm 3 they were treated with either sham RT or 15 Gy in 1 fraction. At different time points, days 3, 9, and 16 for controls and days 4, 7, 12, 21, 30, and 40 after irradiation, 2 to 3 mice were assessed with dynamic FDG-PET acquisition over 2 hours. Immediately after the FDG-PET the tumors were harvested for global gene expression analysis and immunohistochemical evaluation of GLUT1 and HK2. Different analytic parameters were used to process the dynamic PET data. Results: Radiation had no effect on key genes involved in FDG uptake and metabolism but did alter other genes in the HIF1α and glucose transport–related pathways. In contrast to the lack of effect on gene expression, changes in the protein expression patterns of the key genes GLUT1/SLC2A1 and HK2 were observed after radiation treatment. The changes in GLUT1 protein expression showed some correlation with dynamic FDG-PET parameters, such as the kinetic index. Conclusion: 18 F-fluorodeoxyglucose positron emission tomography changes after RT would seem to represent an altered metabolic state and not a direct effect on the key genes regulating FDG uptake and metabolism

  14. Ancestry as a potential modifier of gene expression in breast tumors from Colombian women.

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    Silvia J Serrano-Gómez

    Full Text Available Hispanic/Latino populations are a genetically admixed and heterogeneous group, with variable fractions of European, Indigenous American and African ancestries. The molecular profile of breast cancer has been widely described in non-Hispanic Whites but equivalent knowledge is lacking in Hispanic/Latinas. We have previously reported that the most prevalent breast cancer intrinsic subtype in Colombian women was Luminal B as defined by St. Gallen 2013 criteria. In this study we explored ancestry-associated differences in molecular profiles of Luminal B tumors among these highly admixed women.We performed whole-transcriptome RNA-seq analysis in 42 Luminal tumors (21 Luminal A and 21 Luminal B from Colombian women. Genetic ancestry was estimated from a panel of 80 ancestry-informative markers (AIM. We categorized patients according to Luminal subtype and to the proportion of European and Indigenous American ancestry and performed differential expression analysis comparing Luminal B against Luminal A tumors according to the assigned ancestry groups.We found 5 genes potentially modulated by genetic ancestry: ERBB2 (log2FC = 2.367, padj<0.01, GRB7 (log2FC = 2.327, padj<0.01, GSDMB (log2FC = 1.723, padj<0.01, MIEN1 (log2FC = 2.195, padj<0.01 and ONECUT2 (log2FC = 2.204, padj<0.01. In the replication set we found a statistical significant association between ERBB2 expression with Indigenous American ancestry (p = 0.02, B = 3.11. This association was not biased by the distribution of HER2+ tumors among the groups analyzed.Our results suggest that genetic ancestry in Hispanic/Latina women might modify ERBB2 gene expression in Luminal tumors. Further analyses are needed to confirm these findings and explore their prognostic value.

  15. Gene delivery in conjunction with gold nanoparticle and tumor treating electric field

    Science.gov (United States)

    Tiwari, Pawan K.; Soo Lee, Yeon

    2013-08-01

    The advances in electrotherapy to treat the diseased biological cell instigate its extension in gene therapy through the delivery of gene into the nucleus. The objective of this study is to investigate the application of moderate intensity alternating electric field, also known as tumor treating electric field on a carrier system consisting of a charged gene complex conjugated to the surface of a gold nanoparticle. The gene delivery mechanism relies on the magnitude and direction of the induced electric field inside the cytoplasm in presence of carrier system. The induced electric field strength is significant in breaking the gene complex-gold nanoparticle bonding, and exerting an electric force pushing the charged gene into the nucleus. The electric force orientation is dependent on the aspect ratio (AR) of the gold nanoparticle and a relationship between them is studied via Maxwell two-dimensional (2D) finite element simulation analyzer. The development of charge density on the surface of carrier system and the required electric field strength to break the bonding are investigated utilizing the Gouy-Chapman-Grahame-Stern (GCGS) theoretical model. A carrier system having the aspect ratio of the gold nanoparticle in the range 1 < AR ≤ 5 and AR = 1 are substantial delivering cationic and anionic genes into the nucleus, respectively.

  16. Pan-Cancer Analysis of lncRNA Regulation Supports Their Targeting of Cancer Genes in Each Tumor Context

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    Hua-Sheng Chiu

    2018-04-01

    Full Text Available Summary: Long noncoding RNAs (lncRNAs are commonly dysregulated in tumors, but only a handful are known to play pathophysiological roles in cancer. We inferred lncRNAs that dysregulate cancer pathways, oncogenes, and tumor suppressors (cancer genes by modeling their effects on the activity of transcription factors, RNA-binding proteins, and microRNAs in 5,185 TCGA tumors and 1,019 ENCODE assays. Our predictions included hundreds of candidate onco- and tumor-suppressor lncRNAs (cancer lncRNAs whose somatic alterations account for the dysregulation of dozens of cancer genes and pathways in each of 14 tumor contexts. To demonstrate proof of concept, we showed that perturbations targeting OIP5-AS1 (an inferred tumor suppressor and TUG1 and WT1-AS (inferred onco-lncRNAs dysregulated cancer genes and altered proliferation of breast and gynecologic cancer cells. Our analysis indicates that, although most lncRNAs are dysregulated in a tumor-specific manner, some, including OIP5-AS1, TUG1, NEAT1, MEG3, and TSIX, synergistically dysregulate cancer pathways in multiple tumor contexts. : Chiu et al. present a pan-cancer analysis of lncRNA regulatory interactions. They suggest that the dysregulation of hundreds of lncRNAs target and alter the expression of cancer genes and pathways in each tumor context. This implies that hundreds of lncRNAs can alter tumor phenotypes in each tumor context. Keywords: lncRNA, regulation, modulation, cancer gene, pan-cancer, noncoding RNA, microRNA, RNA-binding proteins, interactome

  17. Gene alterations in radiation-induced F344 rat lung tumors

    International Nuclear Information System (INIS)

    Kelly, G.; Hahn, F.F.

    1994-01-01

    The p53 tumor suppressor gene is frequently altered in all major histopathologic types of human lung tumors. Reported p53 mutations include base substitutions, allelic loss, rearrangements, and deletions. Point mutations resulting in base substitutions are clustered within a highly conserved region of the gene encoding exons 508, and mutations in this region substantially extend the half-life of the p53 protein. In addition to its prominent importance in lung carcinogenesis, the p53 gene plays a critical role in the cellular response to genetic damage caused by radiation. Specifically, the protein product of p53 induces a pause or block at the G 1 to S boundary of the cell cycle following radiation-caused DNA damage. This G 1 block may allow the cell time to repair the damaged DNA prior to replication. Cells lacking a functional p53 protein fail to pause for repair and consequently accumulate mutations in the genome at an accelerated rate. p53 has also been implicated as a controlling factor in apoptosis or in programmed cell death induced by DNA-damaging agents, such as ionizing radiation. The p53 gene is mutated in approximately 50% of squamous cell carcinomas from uranium miners who inhaled high doses of radon daughters. The purpose of the present study was to determine if a similar percentage of squamous cell carcinomas with p53 mutations developed in the lungs of rats exposed to aerosols of 239 PuO 2

  18. Tumor Suppressor Genes within Common Fragile Sites Are Active Players in the DNA Damage Response.

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    Idit Hazan

    2016-12-01

    Full Text Available The role of common fragile sites (CFSs in cancer remains controversial. Two main views dominate the discussion: one suggests that CFS loci are hotspots of genomic instability leading to inactivation of genes encoded within them, while the other view proposes that CFSs are functional units and that loss of the encoded genes confers selective pressure, leading to cancer development. The latter view is supported by emerging evidence showing that expression of a given CFS is associated with genome integrity and that inactivation of CFS-resident tumor suppressor genes leads to dysregulation of the DNA damage response (DDR and increased genomic instability. These two viewpoints of CFS function are not mutually exclusive but rather coexist; when breaks at CFSs are not repaired accurately, this can lead to deletions by which cells acquire growth advantage because of loss of tumor suppressor activities. Here, we review recent advances linking some CFS gene products with the DDR, genomic instability, and carcinogenesis and discuss how their inactivation might represent a selective advantage for cancer cells.

  19. Remodeling epigenetic modifications at tumor suppressor gene promoters with bovine oocyte extract.

    Science.gov (United States)

    Wang, Zhenfei; Yue, Yongli; Han, Pengyong; Sa, Rula; Ren, Xiaolv; Wang, Jie; Bai, Haidong; Yu, Haiquan

    2013-09-01

    Epigenetic silencing of tumor suppressor genes by aberrant DNA methylation and histone modifications at their promoter regions plays an important role in the initiation and progression of cancer. The therapeutic effect of the widely used epigenetic drugs, including DNA methyltransferase inhibitors and histone deacetylase inhibitors, remains unsatisfactory. One important underlying factor in the ineffectiveness of these drugs is that their actions lack specificity. To investigate whether oocyte extract can be used for epigenetic re-programming of cancer cells, H460 human lung cancer cells were reversibly permeabilized and incubated with bovine oocyte extract. Bisulfite sequencing showed that bovine oocyte extract induced significant demethylation at hypermethylated promoter CpG islands of the tumor suppressor genes RUNX3 and CDH1; however, the DNA methylation levels of repetitive sequences were not affected. Chromatin immunoprecipitation showed that bovine oocyte extract significantly reduced transcriptionally repressive histone modifications and increased transcriptionally activating histone modifications at the promoter regions of RUNX3 and CDH1. Bovine oocyte extract reactivated the expression of RUNX3 and CDH1 at both the messenger RNA and the protein levels without up-regulating the transcription of pluripotency-associated genes. At the functional level, anchorage-independent proliferation, migration and invasion of H460 cells was strongly inhibited. These results demonstrate that bovine oocyte extract reactivates epigenetically silenced tumor suppressor genes by remodeling the epigenetic modifications at their promoter regions. Bovine oocyte extract may provide a useful tool for investigating epigenetic mechanisms in cancer and a valuable source for developing novel safe therapeutic approaches that target epigenetic alterations. Copyright © 2013 International Society for Cellular Therapy. Published by Elsevier Inc. All rights reserved.

  20. Genetic interactions between the Drosophila tumor suppressor gene ept and the stat92E transcription factor.

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    M Melissa Gilbert

    2009-09-01

    Full Text Available Tumor Susceptibility Gene-101 (TSG101 promotes the endocytic degradation of transmembrane proteins and is implicated as a mutational target in cancer, yet the effect of TSG101 loss on cell proliferation in vertebrates is uncertain. By contrast, Drosophila epithelial tissues lacking the TSG101 ortholog erupted (ept develop as enlarged undifferentiated tumors, indicating that the gene can have anti-growth properties in a simple metazoan. A full understanding of pathways deregulated by loss of Drosophila ept will aid in understanding potential links between mammalian TSG101 and growth control.We have taken a genetic approach to the identification of pathways required for excess growth of Drosophila eye-antennal imaginal discs lacking ept. We find that this phenotype is very sensitive to the genetic dose of stat92E, the transcriptional effector of the Jak-Stat signaling pathway, and that this pathway undergoes strong activation in ept mutant cells. Genetic evidence indicates that stat92E contributes to cell cycle deregulation and excess cell size phenotypes that are observed among ept mutant cells. In addition, autonomous Stat92E hyper-activation is associated with altered tissue architecture in ept tumors and an effect on expression of the apical polarity determinant crumbs.These findings identify ept as a cell-autonomous inhibitor of the Jak-Stat pathway and suggest that excess Jak-Stat signaling makes a significant contribution to proliferative and tissue architectural phenotypes that occur in ept mutant tissues.

  1. Expression of the Circadian Clock Genes Pert, Per2 in Sporadic, Familial Breast Tumors

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    Sherry L. Winter

    2007-10-01

    Full Text Available There is a growing body of evidence implicating aberrant circadian clock expression in the development of cancer. Based on our initial experiments identifying a putative interaction between BRCA1, the clock proteins Per1, Per2, as well as the reported involvement of the circadian clock in the development of cancer, we have performed an expression analysis of the circadian clock genes Per1, Per2 in both sporadic, familial primary breast tumors, normal breast tissues using real-time polymerase chain reaction. Significantly decreased levels of Per1 were observed between sporadic tumors, normal samples (P < .00001, as well as a further significant decrease between familial, sporadic breast tumors for both Per1 (P < .00001, Per2 (P < .00001. Decreased Per1 was also associated with estrogen receptor negativity (53% vs 15%, P = .04. These results suggest a role for both Perl, Per2 in normal breast function, show for the first time that deregulation of the circadian clock may be an important factor in the development of familial breast cancer. Aberrant expression of circadian clock genes could have important consequences on the transactivation of downstream targets that control the cell cycle, on the ability of cells to undergo apoptosis, potentially promoting carcinogenesis.

  2. Tumor-specific mutations in low-frequency genes affect their functional properties.

    Science.gov (United States)

    Erdem-Eraslan, Lale; Heijsman, Daphne; de Wit, Maurice; Kremer, Andreas; Sacchetti, Andrea; van der Spek, Peter J; Sillevis Smitt, Peter A E; French, Pim J

    2015-05-01

    Causal genetic changes in oligodendrogliomas (OD) with 1p/19q co-deletion include mutations in IDH1, IDH2, CIC, FUBP1, TERT promoter and NOTCH1. However, it is generally assumed that more somatic mutations are required for tumorigenesis. This study aimed to establish whether genes mutated at low frequency can be involved in OD initiation and/or progression. We performed whole-genome sequencing on three anaplastic ODs with 1p/19q co-deletion. To estimate mutation frequency, we performed targeted resequencing on an additional 39 ODs. Whole-genome sequencing identified a total of 55 coding mutations (range 8-32 mutations per tumor), including known abnormalities in IDH1, IDH2, CIC and FUBP1. We also identified mutations in genes, most of which were previously not implicated in ODs. Targeted resequencing on 39 additional ODs confirmed that these genes are mutated at low frequency. Most of the mutations identified were predicted to have a deleterious functional effect. Functional analysis on a subset of these genes (e.g. NTN4 and MAGEH1) showed that the mutation affects the subcellular localization of the protein (n = 2/12). In addition, HOG cells stably expressing mutant GDI1 or XPO7 showed altered cell proliferation compared to those expressing wildtype constructs. Similarly, HOG cells expressing mutant SASH3 or GDI1 showed altered migration. The significantly higher rate of predicted deleterious mutations, the changes in subcellular localization and the effects on proliferation and/or migration indicate that many of these genes functionally may contribute to gliomagenesis and/or progression. These low-frequency genes and their affected pathways may provide new treatment targets for this tumor type.

  3. Methylation and expression profiles of MGMT gene in thymic epithelial tumors.

    Science.gov (United States)

    Mokhtar, Mohamed; Kondo, Kazuya; Namura, Toshiaki; Ali, Abdellah H K; Fujita, Yui; Takai, Chikako; Takizawa, Hiromitsu; Nakagawa, Yasushi; Toba, Hiroaki; Kajiura, Koichiro; Yoshida, Mitsuteru; Kawakami, Gyokei; Sakiyama, Shoji; Tangoku, Akira

    2014-02-01

    A key challenge in diagnosis and treatment of thymic epithelial tumors (TET) is in improving our understanding of the genetic and epigenetic changes of these relatively rare tumors. Methylation specific PCR (MSP) and immunohistochemistry were applied to 66 TET to profile the methylation status of DNA repair gene O6-methylguanine DNA methyltransferase (MGMT) and its protein expression in TET to clarify the association between MGMT status and clinicopathological features, response to chemotherapy and overall survival. MGMT methylation was significantly more frequent in thymic carcinoma than in thymoma (17/23, 74% versus 13/44, 29%; PMGMT protein was significantly more frequent in thymic carcinoma than in thymoma (20/23, 87% versus 10/44, 23%; PMGMT methylation and loss of its protein expression (PMGMT methylation and loss of expression were significantly more frequent in advanced thymic epithelial tumors (III/IV) than in early tumors (I/II). MGMT methylation plays a soul role in development of TET, especially in thymic carcinoma. Therefore, translation of our results from basic molecular research to clinical practice may have important implication for considering MGMT methylation as a marker and a target of future therapies in TET. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

  4. Mouse mammary tumor virus-like gene sequences are present in lung patient specimens

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    Rodríguez-Padilla Cristina

    2011-09-01

    Full Text Available Abstract Background Previous studies have reported on the presence of Murine Mammary Tumor Virus (MMTV-like gene sequences in human cancer tissue specimens. Here, we search for MMTV-like gene sequences in lung diseases including carcinomas specimens from a Mexican population. This study was based on our previous study reporting that the INER51 lung cancer cell line, from a pleural effusion of a Mexican patient, contains MMTV-like env gene sequences. Results The MMTV-like env gene sequences have been detected in three out of 18 specimens studied, by PCR using a specific set of MMTV-like primers. The three identified MMTV-like gene sequences, which were assigned as INER6, HZ101, and HZ14, were 99%, 98%, and 97% homologous, respectively, as compared to GenBank sequence accession number AY161347. The INER6 and HZ-101 samples were isolated from lung cancer specimens, and the HZ-14 was isolated from an acute inflammatory lung infiltrate sample. Two of the env sequences exhibited disruption of the reading frame due to mutations. Conclusion In summary, we identified the presence of MMTV-like gene sequences in 2 out of 11 (18% of the lung carcinomas and 1 out of 7 (14% of acute inflamatory lung infiltrate specimens studied of a Mexican Population.

  5. Nonviral gene therapy in vivo with PAM-RG4/apoptin as a potential brain tumor therapeutic.

    Science.gov (United States)

    An, Songhie; Nam, Kihoon; Choi, Sunghyun; Bai, Cheng Z; Lee, Yan; Park, Jong-Sang

    2013-01-01

    Glioma is still one of the most complicated forms of brain tumor to remove completely due to its location and the lack of an efficient means to specifically eliminate tumor cells. For these reasons, this study has examined the effectiveness of a nonviral gene therapy approach utilizing a tumor-selective killer gene on a brain tumor xenograft model. The therapeutic apoptin gene was recombined into the JDK plasmid and delivered into human brain tumor cells (U87MG) by using a polyamidoamine dendrimer with an arginine surface (PAM-RG4). Studies in vitro showed that the PAM-RG4/apoptin plasmid polyplex exhibited a particularly high transfection activity of .40%. Terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) assay, 4',6-Diamidino-2-phenylindole (DAPI) TUNEL assay, DAPI staining, and caspase-3 activity assay verified that the tumor cells had undergone apoptosis induced by apoptin. For in vivo studies, the polyplex was injected into tumors, which were induced by injecting U87MG cells intradermally into nude mice. Based on hematoxylin and eosin staining, epidermal growth factor receptor immunohistochemistry results and tumor volume measurement results, tumor growth was effectively inhibited and no specific edema, irritation, or other harm to the skin was observed after polyplex injection. The in vivo expression of apoptin and the induction of apoptosis were verified by reverse-transcription polymerase chain reaction analysis, TUNEL assay, and DAPI staining. The PAM-RG4/apoptin gene polyplex is a strong candidate for brain tumor therapeutics because of the synergistic effect of the carrier's high transfection efficiency (35%-40%) in glioma cells and the selective apoptosis-inducing activity of apoptin in tumor cells.

  6. A study on tumor suppressor genes mutations associated with different pathological colorectal lesions

    International Nuclear Information System (INIS)

    Matar, S.N.A.

    2011-01-01

    Colorectal cancer (CRC) is the second leading cause of cancer-related death in the Western world. In Egypt; there is an increasing incidence of the disease, especially among patients ≤40 years age. While CRC have been reported in low incidence rate in developing countries, it is the third most common tumor in male and the fifth common tumor in females in Egypt. Early diagnosis and surgical interference guarantee long survival of most CRC patients. Early diagnosis is impeded by the disease onset at young age and imprecise symptoms at the initial stages of the disease. As in most solid tumors, the malignant transformation of colonic epithelial cells is to arise through a multistep process during which they acquire genetic changes involving the activation of proto-oncogenes and the loss of tumor suppressor genes. Recently, a candidate tumor suppressor gene, KLF6, which is mapped to chromosome 10p, was found to be frequently mutated in a number of cancers. There are some evidences suggesting that the disruption of the functional activity of KLF6 gene products may be one of the early events in tumor genesis of the colon. The main objective of the present study was to detect mutational changes of KLF6 tumor suppressor gene and to study the loss of heterozygosity (LOH) markers at chromosome 10p15 (KLF6 locus) in colorectal lesions and colorectal cancer in Egyptian patients. The patients included in this study were 83 presented with different indications for colonoscopic examination. Selecting patients with colorectal pre-cancerous lesions or colorectal cancer was done according to the results of tissue biopsy from lesion and adjacent normal. The patients were classified into three main groups; (G I) Cancerous group, (G II) polyps group including patients with adenomatous polyps (AP), familial adenomatous polyps (FAP) and hyperplastic polyps (HP) and (G III) Inflammatory Bowel Diseases (IBD) including patients with ulcerative colitis (UC) and Crohn's disease (CD

  7. Centrosome clustering and cyclin D1 gene amplification in double minutes are common events in chromosomal unstable bladder tumors

    International Nuclear Information System (INIS)

    Rey, Javier del; Prat, Esther; Ponsa, Immaculada; Lloreta, Josep; Gelabert, Antoni; Algaba, Ferran; Camps, Jordi; Miró, Rosa

    2010-01-01

    Aneuploidy, centrosome abnormalities and gene amplification are hallmarks of chromosome instability (CIN) in cancer. Yet there are no studies of the in vivo behavior of these phenomena within the same bladder tumor. Twenty-one paraffin-embedded bladder tumors were analyzed by conventional comparative genome hybridization and fluorescence in situ hybridization (FISH) with a cyclin D1 gene (CCND1)/centromere 11 dual-color probe. Immunofluorescent staining of α, β and γ tubulin was also performed. Based on the CIN index, defined as the percentage of cells not displaying the modal number for chromosome 11, tumors were classified as CIN-negative and CIN-positive. Fourteen out of 21 tumors were considered CIN-positive. All T1G3 tumors were included in the CIN-positive group whereas the majority of Ta samples were classified as CIN-negative tumors. Centrosome clustering was observed in six out of 12 CIN-positive tumors analyzed. CCND1 amplification in homogeneously staining regions was present in six out of 14 CIN-positive tumors; three of them also showed amplification of this gene in double minutes. Complex in vivo behavior of CCND1 amplicon in bladder tumor cells has been demonstrated by accurate FISH analysis on paraffin-embedded tumors. Positive correlation between high heterogeneity, centrosome abnormalities and CCND1 amplification was found in T1G3 bladder carcinomas. This is the first study to provide insights into the coexistence of CCND1 amplification in homogeneously staining regions and double minutes in primary bladder tumors. It is noteworthy that those patients whose tumors showed double minutes had a significantly shorter overall survival rate (p < 0.001)

  8. In Silico Analysis of Microarray-Based Gene Expression Profiles Predicts Tumor Cell Response to Withanolides

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    Thomas Efferth

    2012-05-01

    Full Text Available Withania somnifera (L. Dunal (Indian ginseng, winter cherry, Solanaceae is widely used in traditional medicine. Roots are either chewed or used to prepare beverages (aqueous decocts. The major secondary metabolites of Withania somnifera are the withanolides, which are C-28-steroidal lactone triterpenoids. Withania somnifera extracts exert chemopreventive and anticancer activities in vitro and in vivo. The aims of the present in silico study were, firstly, to investigate whether tumor cells develop cross-resistance between standard anticancer drugs and withanolides and, secondly, to elucidate the molecular determinants of sensitivity and resistance of tumor cells towards withanolides. Using IC50 concentrations of eight different withanolides (withaferin A, withaferin A diacetate, 3-azerininylwithaferin A, withafastuosin D diacetate, 4-B-hydroxy-withanolide E, isowithanololide E, withafastuosin E, and withaperuvin and 19 established anticancer drugs, we analyzed the cross-resistance profile of 60 tumor cell lines. The cell lines revealed cross-resistance between the eight withanolides. Consistent cross-resistance between withanolides and nitrosoureas (carmustin, lomustin, and semimustin was also observed. Then, we performed transcriptomic microarray-based COMPARE and hierarchical cluster analyses of mRNA expression to identify mRNA expression profiles predicting sensitivity or resistance towards withanolides. Genes from diverse functional groups were significantly associated with response of tumor cells to withaferin A diacetate, e.g. genes functioning in DNA damage and repair, stress response, cell growth regulation, extracellular matrix components, cell adhesion and cell migration, constituents of the ribosome, cytoskeletal organization and regulation, signal transduction, transcription factors, and others.

  9. Pan-Cancer Analysis of lncRNA Regulation Supports Their Targeting of Cancer Genes in Each Tumor Context.

    Science.gov (United States)

    Chiu, Hua-Sheng; Somvanshi, Sonal; Patel, Ektaben; Chen, Ting-Wen; Singh, Vivek P; Zorman, Barry; Patil, Sagar L; Pan, Yinghong; Chatterjee, Sujash S; Sood, Anil K; Gunaratne, Preethi H; Sumazin, Pavel

    2018-04-03

    Long noncoding RNAs (lncRNAs) are commonly dysregulated in tumors, but only a handful are known to play pathophysiological roles in cancer. We inferred lncRNAs that dysregulate cancer pathways, oncogenes, and tumor suppressors (cancer genes) by modeling their effects on the activity of transcription factors, RNA-binding proteins, and microRNAs in 5,185 TCGA tumors and 1,019 ENCODE assays. Our predictions included hundreds of candidate onco- and tumor-suppressor lncRNAs (cancer lncRNAs) whose somatic alterations account for the dysregulation of dozens of cancer genes and pathways in each of 14 tumor contexts. To demonstrate proof of concept, we showed that perturbations targeting OIP5-AS1 (an inferred tumor suppressor) and TUG1 and WT1-AS (inferred onco-lncRNAs) dysregulated cancer genes and altered proliferation of breast and gynecologic cancer cells. Our analysis indicates that, although most lncRNAs are dysregulated in a tumor-specific manner, some, including OIP5-AS1, TUG1, NEAT1, MEG3, and TSIX, synergistically dysregulate cancer pathways in multiple tumor contexts. Copyright © 2018 The Author(s). Published by Elsevier Inc. All rights reserved.

  10. Self-association of the WT1 tumor suppressor gene product

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    Bruening, W.; Nakagama, H.: Bardessy, N. [McGill Univ., Montreal (Canada)] [and others

    1994-09-01

    Wilms` tumor (WT), an embryonal malignancy of the kidney, occurs most frequently in children under the age of 5 years, affecting {approximately}1 in 10,000 individuals. The WT1 tumor suppressor gene, residing at 11p13, is structurally altered in {approximately}10-15% of WT cases. Individuals with germline mutations within the WT1 gene suffer from predisposition to WT and developmental defects of the urogenital system. Patients with heterozygous deletions of the WT1 gene, or mutations predicted to cause inactivation of one WT1 allele, suffer relatively mild genital system defects (notably hypospadias and cryptorchidism in males) and a predisposition to WT. These results suggest that developing genital system development is sensitive to the absolute concentrations of the WT1 gene products. Patients with missense mutations within the WT1 gene, however, can suffer from a much more severe disorder known as Denys-Drash syndrome (DDS). This syndrome is characterized by intersex disorders, renal nephropathy, and a predisposition to WTs. The increased severity of the developmental defects associated with DDS, compared to those individuals with mild genital system anomalies and WTs, suggests that mutations defined in patients with DDS behave in a dominant-negative fashion. We have identified a novel WT1 mutation in a patient with DDS. This mutation, predicted to produce a truncated WT1 polypeptide encompassing exons 1, 2, and 3, defines a domain capable of behaving as an antimorph. We have also demonstrated that WT1 can self-associate in vivo using yeast two-hybrid systems. Deletion analysis have mapped the interacting domains to the amino terminus of the WT1 polypeptide, within exons 1 and 2. These results provide a molecular mechanism to explain how WT1 mutations can function in a dominant-negative fashion to eliminate wild-type WT1 activity, leading to DDS.

  11. Cytokines and tumor metastasis gene variants in oral cancer and precancer in Puerto Rico.

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    Esther Erdei

    Full Text Available A cross-sectional epidemiological study explored genetic susceptibility to oral precancer and cancer in Puerto Rico (PR.Three hundred three individuals with a benign oral condition, oral precancer (oral epithelial hyperplasia/hyperkeratosis, oral epithelial dysplasia, or oral squamous cell carcinoma (SCCA were identified via PR pathology laboratories. A standardized, structured questionnaire obtained information on epidemiological variables; buccal cells were collected for genetic analysis. Genotyping was performed using Taqman® assays. Allelic frequencies of single nucleotide polymorphisms (SNPs were evaluated in cytokine genes and genes influencing tumor metastasis. Risk estimates for a diagnosis of oral precancer or SCCA while having a variant allele were generated using logistic regression. Adjusted models controlled for age, gender, ancestry, education, smoking and alcohol consumption.Relative to persons with a benign oral lesion, individuals with homozygous recessive allelic variants of tumor necrosis factor (TNF-α -238 A/G SNP had a reduced odds of having an oral precancer (ORadjusted = 0.15; 95% CI 0.03-0.70. The transforming growth factor beta-1 (TGFβ-1 -509 C/T polymorphism was inversely associated with having an oral SCCA among persons homozygous for the recessive variant (ORcrude = 0.27; 95% CI 0.09-0.79. The matrix metalloproteinase gene (MMP-1 variant, rs5854, was associated with oral SCCA; participants with even one variant allele were more likely to have oral SCCA (ORadjusted = 2.62, 95% CI 1.05-6.53 compared to people with ancestral alleles.Our exploratory analyses suggest that genetic alterations in immune system genes and genes with metastatic potential are associated with oral precancer and SCCA risk in PR.

  12. Cytokines and tumor metastasis gene variants in oral cancer and precancer in Puerto Rico.

    Science.gov (United States)

    Erdei, Esther; Luo, Li; Sheng, Huiping; Maestas, Erika; White, Kirsten A M; Mackey, Amanda; Dong, Yan; Berwick, Marianne; Morse, Douglas E

    2013-01-01

    A cross-sectional epidemiological study explored genetic susceptibility to oral precancer and cancer in Puerto Rico (PR). Three hundred three individuals with a benign oral condition, oral precancer (oral epithelial hyperplasia/hyperkeratosis, oral epithelial dysplasia), or oral squamous cell carcinoma (SCCA) were identified via PR pathology laboratories. A standardized, structured questionnaire obtained information on epidemiological variables; buccal cells were collected for genetic analysis. Genotyping was performed using Taqman® assays. Allelic frequencies of single nucleotide polymorphisms (SNPs) were evaluated in cytokine genes and genes influencing tumor metastasis. Risk estimates for a diagnosis of oral precancer or SCCA while having a variant allele were generated using logistic regression. Adjusted models controlled for age, gender, ancestry, education, smoking and alcohol consumption. Relative to persons with a benign oral lesion, individuals with homozygous recessive allelic variants of tumor necrosis factor (TNF-α) -238 A/G SNP had a reduced odds of having an oral precancer (ORadjusted = 0.15; 95% CI 0.03-0.70). The transforming growth factor beta-1 (TGFβ-1 -509 C/T) polymorphism was inversely associated with having an oral SCCA among persons homozygous for the recessive variant (ORcrude = 0.27; 95% CI 0.09-0.79). The matrix metalloproteinase gene (MMP-1) variant, rs5854, was associated with oral SCCA; participants with even one variant allele were more likely to have oral SCCA (ORadjusted = 2.62, 95% CI 1.05-6.53) compared to people with ancestral alleles. Our exploratory analyses suggest that genetic alterations in immune system genes and genes with metastatic potential are associated with oral precancer and SCCA risk in PR.

  13. Gene expression profiles of progestin-induced canine mammary hyperplasia and spontaneous mammary tumors.

    Science.gov (United States)

    Rao, N A S; van Wolferen, M E; Gracanin, A; Bhatti, S F M; Krol, M; Holstege, F C; Mol, J A

    2009-05-01

    Spontaneous mammary tumors are the most prevalent type of neoplasms in women as well as in female dogs. Although ovarian hormones estrogen and progesterone are known to play a key role in mammary tumorigenesis, conflicting reports have been obtained from in vivo and in vitro studies concerning the role of especially progesterone in mammary tumorigenesis. Prolonged exposure to high concentrations of progesterone during the unusually long luteal phase of the estrous cycle is suspected to be the key event in canine mammary tumorigenesis. Accordingly, previous studies have shown the development of mammary hyperplasia in dogs upon prolonged progestin administration. In this study, a dog-specific cDNA microarray was used to identify oncogenic determinants in progestin-induced canine hyperplasia (CMH) and spontaneous mammary tumors (CMC) by comparing expression profiles to those obtained from mammary glands of healthy dogs. The CMH profile showed elevated expression of genes involved in cell proliferation such as PCNA, NPY, RAN and also alterations in expression of transcription factors and cell adhesion molecules. Whereas in CMC, major alterations to the expression of genes involved in cell motility, cytoskeletal organization and extra cellular matrix production was evident besides differential expression of cell proliferation inducing genes. The overall gene expression profile of CMH was related to cell proliferation where as that of CMC was associated with both cell proliferation as well as neoplastic transformation. In conclusion, our findings support a strong cell proliferation inducing potential of progestins in the canine mammary gland. Moreover, deregulated genes identified in CMC are potentially involved in their malignant and may serve as prospective therapeutic targets.

  14. The role of UV induced lesions in skin carcinogenesis: an overview of oncogene and tumor suppressor gene modifications in xeroderma pigmentosum skin tumors.

    Science.gov (United States)

    Daya-Grosjean, Leela; Sarasin, Alain

    2005-04-01

    Xeroderma pigmentosum (XP), a rare hereditary syndrome, is characterized by a hypersensitivity to solar irradiation due to a defect in nucleotide excision repair resulting in a predisposition to squamous and basal cell carcinomas as well as malignant melanomas appearing at a very early age. The mutator phenotype of XP cells is evident by the higher levels of UV specific modifications found in key regulatory genes in XP skin tumors compared to those in the same tumor types from the normal population. Thus, XP provides a unique model for the study of unrepaired DNA lesions, mutations and skin carcinogenesis. The high level of ras oncogene activation, Ink4a-Arf and p53 tumor suppressor gene modifications as well as alterations of the different partners of the mitogenic sonic hedgehog signaling pathway (patched, smoothened and sonic hedgehog), characterized in XP skin tumors have clearly demonstrated the major role of the UV component of sunlight in the development of skin tumors. The majority of the mutations are C to T or tandem CC to TT UV signature transitions, occurring at bipyrimidine sequences, the specific targets of UV induced lesions. These characteristics are also found in the same genes modified in sporadic skin cancers but with lower frequencies confirming the validity of studying the XP model. The knowledge gained by studying XP tumors has given us a greater perception of the contribution of genetic predisposition to cancer as well as the consequences of the many alterations which modulate the activities of different genes affecting crucial pathways vital for maintaining cell homeostasis.

  15. The role of UV induced lesions in skin carcinogenesis: an overview of oncogene and tumor suppressor gene modifications in xeroderma pigmentosum skin tumors

    International Nuclear Information System (INIS)

    Daya-Grosjean, Leela; Sarasin, Alain

    2005-01-01

    Xeroderma pigmentosum (XP), a rare hereditary syndrome, is characterized by a hypersensitivity to solar irradiation due to a defect in nucleotide excision repair resulting in a predisposition to squamous and basal cell carcinomas as well as malignant melanomas appearing at a very early age. The mutator phenotype of XP cells is evident by the higher levels of UV specific modifications found in key regulatory genes in XP skin tumors compared to those in the same tumor types from the normal population. Thus, XP provides a unique model for the study of unrepaired DNA lesions, mutations and skin carcinogenesis. The high level of ras oncogene activation, Ink4a-Arf and p53 tumor suppressor gene modifications as well as alterations of the different partners of the mitogenic sonic hedgehog signaling pathway (patched, smoothened and sonic hedgehog), characterized in XP skin tumors have clearly demonstrated the major role of the UV component of sunlight in the development of skin tumors. The majority of the mutations are C to T or tandem CC to TT UV signature transitions, occurring at bipyrimidine sequences, the specific targets of UV induced lesions. These characteristics are also found in the same genes modified in sporadic skin cancers but with lower frequencies confirming the validity of studying the XP model. The knowledge gained by studying XP tumors has given us a greater perception of the contribution of genetic predisposition to cancer as well as the consequences of the many alterations which modulate the activities of different genes affecting crucial pathways vital for maintaining cell homeostasis

  16. The role of UV induced lesions in skin carcinogenesis: an overview of oncogene and tumor suppressor gene modifications in xeroderma pigmentosum skin tumors

    Energy Technology Data Exchange (ETDEWEB)

    Daya-Grosjean, Leela [Laboratory of Genetic Instability and Cancer, UPR2169 CNRS, IFR 54, Institut Gustave Roussy, 39, rue Camille Desmoulins, 94805 Villejuif Cedex (France)]. E-mail: daya@igr.fr; Sarasin, Alain [Laboratory of Genetic Instability and Cancer, UPR2169 CNRS, IFR 54, Institut Gustave Roussy, 39, rue Camille Desmoulins, 94805 Villejuif Cedex (France)

    2005-04-01

    Xeroderma pigmentosum (XP), a rare hereditary syndrome, is characterized by a hypersensitivity to solar irradiation due to a defect in nucleotide excision repair resulting in a predisposition to squamous and basal cell carcinomas as well as malignant melanomas appearing at a very early age. The mutator phenotype of XP cells is evident by the higher levels of UV specific modifications found in key regulatory genes in XP skin tumors compared to those in the same tumor types from the normal population. Thus, XP provides a unique model for the study of unrepaired DNA lesions, mutations and skin carcinogenesis. The high level of ras oncogene activation, Ink4a-Arf and p53 tumor suppressor gene modifications as well as alterations of the different partners of the mitogenic sonic hedgehog signaling pathway (patched, smoothened and sonic hedgehog), characterized in XP skin tumors have clearly demonstrated the major role of the UV component of sunlight in the development of skin tumors. The majority of the mutations are C to T or tandem CC to TT UV signature transitions, occurring at bipyrimidine sequences, the specific targets of UV induced lesions. These characteristics are also found in the same genes modified in sporadic skin cancers but with lower frequencies confirming the validity of studying the XP model. The knowledge gained by studying XP tumors has given us a greater perception of the contribution of genetic predisposition to cancer as well as the consequences of the many alterations which modulate the activities of different genes affecting crucial pathways vital for maintaining cell homeostasis.

  17. Mosaic zebrafish transgenesis for functional genomic analysis of candidate cooperative genes in tumor pathogenesis.

    Science.gov (United States)

    Ung, Choong Yong; Guo, Feng; Zhang, Xiaoling; Zhu, Zhihui; Zhu, Shizhen

    2015-03-31

    Comprehensive genomic analysis has uncovered surprisingly large numbers of genetic alterations in various types of cancers. To robustly and efficiently identify oncogenic "drivers" among these tumors and define their complex relationships with concurrent genetic alterations during tumor pathogenesis remains a daunting task. Recently, zebrafish have emerged as an important animal model for studying human diseases, largely because of their ease of maintenance, high fecundity, obvious advantages for in vivo imaging, high conservation of oncogenes and their molecular pathways, susceptibility to tumorigenesis and, most importantly, the availability of transgenic techniques suitable for use in the fish. Transgenic zebrafish models of cancer have been widely used to dissect oncogenic pathways in diverse tumor types. However, developing a stable transgenic fish model is both tedious and time-consuming, and it is even more difficult and more time-consuming to dissect the cooperation of multiple genes in disease pathogenesis using this approach, which requires the generation of multiple transgenic lines with overexpression of the individual genes of interest followed by complicated breeding of these stable transgenic lines. Hence, use of a mosaic transient transgenic approach in zebrafish offers unique advantages for functional genomic analysis in vivo. Briefly, candidate transgenes can be coinjected into one-cell-stage wild-type or transgenic zebrafish embryos and allowed to integrate together into each somatic cell in a mosaic pattern that leads to mixed genotypes in the same primarily injected animal. This permits one to investigate in a faster and less expensive manner whether and how the candidate genes can collaborate with each other to drive tumorigenesis. By transient overexpression of activated ALK in the transgenic fish overexpressing MYCN, we demonstrate here the cooperation of these two oncogenes in the pathogenesis of a pediatric cancer, neuroblastoma that has

  18. Radiosensitivity and gene expression of human lung cancer cells dividing in nude tumor before (anoxic) and after vascular induction

    International Nuclear Information System (INIS)

    Miyamoto, Tadaaki; Ishii, Sachiko; Koto, Masashi; Imai, Reiko; Saegusa, Kimiko; Michikawa, Yuichi; Imai, Takashi

    2003-01-01

    We cloned H2 cell line from IA cell line (human large cell lung cancer) in anoxic cell culture. AH2 nude tumor develops a poor vascular system with rich fibrous component and shows low radiosensitivity compared with IA tumor. In relation to radiosensitivity, we studied the gene expression of the both cell lines grown in culture under an oxic or anoxic condition, and in a nude tumor with a microarray method using 22K custom oligoallele. As a result, we found that the both cells depressed CXCL1 and CXCL gene in anoxic culture condition and depressed or expressed IF127, EBI3, and cytokine like protein C17 gene in a nude tumor. (author)

  19. Radiosensitivity and gene expression of human lung cancer cells dividing in nude tumor before (anoxic) and after vascular induction

    International Nuclear Information System (INIS)

    Miyamoto, Tadaaki; Ishii, Sachiko; Baba, Masayuki; Sugawara, Toshiyuki; Furuno, Aki; Saegusa, Kimiko; Michikawa, Y.; Imai, Takashi

    2004-01-01

    We cloned H2 cell line from IA cell line (human large cell lung cancer) in anoxic cell culture. AH2 nude tumor develops a poor vascular system with rich fibrous component and shows low radiosensitivity compared with IA tumor. In relation to radiosensitivity, we studied the gene expression of the both cell lines grown in culture under an oxic or anoxic condition, and in a nude tumor with a microarray method using 22K custom oligoallele. As a result, we found that the both cells depressed CXCL1 and CXCL gene in anoxic culture condition and depressed or expressed IFI27, EBI3, and cytokine like protein C17 gene in a nude tumor. (author)

  20. Mesenchymal Stem Cell-Based Tumor-Targeted Gene Therapy in Gastrointestinal Cancer

    Science.gov (United States)

    Bao, Qi; Zhao, Yue; Niess, Hanno; Conrad, Claudius; Schwarz, Bettina; Jauch, Karl-Walter; Huss, Ralf; Nelson, Peter J.

    2012-01-01

    Mesenchymal stem (or stromal) cells (MSCs) are nonhematopoietic progenitor cells that can be obtained from bone marrow aspirates or adipose tissue, expanded and genetically modified in vitro, and then used for cancer therapeutic strategies in vivo. Here, we review available data regarding the application of MSC-based tumor-targeted therapy in gastrointestinal cancer, provide an overview of the general history of MSC-based gene therapy in cancer research, and discuss potential problems associated with the utility of MSC-based therapy such as biosafety, immunoprivilege, transfection methods, and distribution in the host. PMID:22530882

  1. Multi-step dimensionality reduction and semi-supervised graph-based tumor classification using gene expression data.

    Science.gov (United States)

    Gui, Jie; Wang, Shu-Lin; Lei, Ying-Ke

    2010-11-01

    Both supervised methods and unsupervised methods have been widely used to solve the tumor classification problem based on gene expression profiles. This paper introduces a semi-supervised graph-based method for tumor classification. Feature extraction plays a key role in tumor classification based on gene expression profiles, and can greatly improve the performance of a classifier. In this paper we propose a novel multi-step dimensionality reduction method for extracting tumor-related features. First the Wilcoxon rank-sum test is used for gene selection. Then gene ranking and discrete cosine transform are combined with principal component analysis for feature extraction. Finally, the performance is evaluated by semi-supervised learning algorithms. To show the validity of the proposed method, we apply it to classify four tumor datasets involving various human normal and tumor tissue samples. The experimental results show that the proposed method is efficient and feasible. Compared with other methods, our method can achieve relatively higher prediction accuracy. Particularly, it is found that semi-supervised method is superior to support vector machines in classification performance. The proposed approach can effectively improve the performance of tumor classification based on gene expression profiles. This work is a meaningful attempt to explore and apply multi-step dimensionality reduction and semi-supervised learning methods in the field of tumor classification. Considering the high classification accuracy, there should be much room for the application of multi-step dimensionality reduction and semi-supervised learning methods to perform tumor classification. Copyright © 2010 Elsevier B.V. All rights reserved.

  2. Enhanced gene expression in tumors after intravenous administration of arginine-, lysine- and leucine-bearing polyethylenimine polyplex.

    Science.gov (United States)

    Aldawsari, Hibah; Raj, Behin Sundara; Edrada-Ebel, RuAngelie; Blatchford, David R; Tate, Rothwelle J; Tetley, Laurence; Dufès, Christine

    2011-10-01

    The potential of gene therapy to treat cancer is currently limited by the low expression of therapeutic genes in the tumors. Because amino acids are known to have excellent properties in cell penetration and gene expression regulation, we investigated if the conjugation of arginine (Arg), lysine (Lys) and leucine (Leu) onto the surface of the gene delivery system polyethylenimine (PEI) could lead to an improved gene expression in tumors. The intravenous administration of Arg-, Lys- and Leu-bearing PEI polyplexes led to a significant increase of gene expression in the tumor, with a β-galactosidase expression amount at least threefold higher than that obtained after treatment with unmodified PEI polyplex. The three amino acid-bearing PEI polyplexes led to similar levels of gene expression in the tumor. The treatments were well tolerated by the mice. Arg-, Lys- and Leu-bearing PEI polyplexes are therefore highly promising gene delivery systems for cancer therapy. Copyright © 2011 Elsevier Inc. All rights reserved.

  3. Overexpression of the p53 tumor suppressor gene product in primary lung adenocarcinomas is associated with cigarette smoking

    NARCIS (Netherlands)

    Westra, W. H.; Offerhaus, G. J.; Goodman, S. N.; Slebos, R. J.; Polak, M.; Baas, I. O.; Rodenhuis, S.; Hruban, R. H.

    1993-01-01

    Mutations in the p53 tumor suppressor gene are frequently observed in primary lung adenocarcinomas, suggesting that these mutations are critical events in the malignant transformation of airway cells. These mutations are often associated with stabilization of the p53 gene product, resulting in the

  4. Ki-ras gene mutations are invariably present in low-grade mucinous tumors of the vermiform appendix.

    Science.gov (United States)

    Zauber, Peter; Berman, Errol; Marotta, Stephen; Sabbath-Solitare, Marlene; Bishop, Timothy

    2011-07-01

    Low-grade mucinous tumors of the appendix appear to have a simple histological structure. Paradoxically, reports have suggested a greater frequency of Ki-ras gene mutation in these lesions than in more complex lesions such as benign colonic adenomas and carcinomas. We assessed several molecular genetic changes, including Ki-ras gene mutations, in a large series of low-grade mucinous tumors of the appendix. We retrospectively ascertained low-grade mucinous tumors of the appendix from computerized pathology records. Extracted DNA was analyzed for APC and DCC gene loss of heterozygosity, microsatellite instability and for the presence of Ki-ras gene mutation using standard molecular techniques. Controls consisted of normal appendices, other appendiceal neoplasms, and ovarian mucinous cystadenomas. A total of 31 low-grade appendiceal mucinous tumors were identified. All were microsatellite stable and none demonstrated loss of heterozygosity for the APC or DCC genes. By contrast, all 31 lesions contained a Ki-ras gene mutation. The presence of a Ki-ras gene mutation in all lesions, with no other molecular changes identified, strongly suggests a possible etiological role of the Ki-ras mutation in the development of this particular lesion of the appendix. Based on other work regarding intestinal bacteria, we hypothesize a relationship between chronic inflammation of the appendix from bacterial overgrowth and Ki-ras gene mutation.

  5. Splice Expression Variation Analysis (SEVA) for Inter-tumor Heterogeneity of Gene Isoform Usage in Cancer.

    Science.gov (United States)

    Afsari, Bahman; Guo, Theresa; Considine, Michael; Florea, Liliana; Kagohara, Luciane T; Stein-O'Brien, Genevieve L; Kelley, Dylan; Flam, Emily; Zambo, Kristina D; Ha, Patrick K; Geman, Donald; Ochs, Michael F; Califano, Joseph A; Gaykalova, Daria A; Favorov, Alexander V; Fertig, Elana J

    2018-01-12

    Current bioinformatics methods to detect changes in gene isoform usage in distinct phenotypes compare the relative expected isoform usage in phenotypes. These statistics model differences in isoform usage in normal tissues, which have stable regulation of gene splicing. Pathological conditions, such as cancer, can have broken regulation of splicing that increases the heterogeneity of the expression of splice variants. Inferring events with such differential heterogeneity in gene isoform usage requires new statistical approaches. We introduce Splice Expression Variability Analysis (SEVA) to model increased heterogeneity of splice variant usage between conditions (e.g., tumor and normal samples). SEVA uses a rank-based multivariate statistic that compares the variability of junction expression profiles within one condition to the variability within another. Simulated data show that SEVA is unique in modeling heterogeneity of gene isoform usage, and benchmark SEVA's performance against EBSeq, DiffSplice, and rMATS that model differential isoform usage instead of heterogeneity. We confirm the accuracy of SEVA in identifying known splice variants in head and neck cancer and perform cross-study validation of novel splice variants. A novel comparison of splice variant heterogeneity between subtypes of head and neck cancer demonstrated unanticipated similarity between the heterogeneity of gene isoform usage in HPV-positive and HPV-negative subtypes and anticipated increased heterogeneity among HPV-negative samples with mutations in genes that regulate the splice variant machinery. These results show that SEVA accurately models differential heterogeneity of gene isoform usage from RNA-seq data. SEVA is implemented in the R/Bioconductor package GSReg. bahman@jhu.edu, ejfertig@jhmi.edu. Supplementary data are available at Bioinformatics online. © The Author (2018). Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com

  6. A small interfering RNA screen of genes involved in DNA repair identifies tumor-specific radiosensitization by POLQ knockdown

    DEFF Research Database (Denmark)

    Higgins, Geoff S; Prevo, Remko; Lee, Yin-Fai

    2010-01-01

    ) and irradiated normal tissue cells (MRC5). Using gammaH2AX foci at 24 hours after IR, we identified several genes, such as BRCA2, Lig IV, and XRCC5, whose knockdown is known to cause increased cell radiosensitivity, thereby validating the primary screening end point. In addition, we identified POLQ (DNA...... radiosensitivity are largely unknown. We have conducted a small interfering RNA (siRNA) screen of 200 genes involved in DNA damage repair aimed at identifying genes whose knockdown increased tumor radiosensitivity. Parallel siRNA screens were conducted in irradiated and unirradiated tumor cells (SQ20B...

  7. Kras gene mutation and RASSF1A, FHIT and MGMT gene promoter hypermethylation: indicators of tumor staging and metastasis in adenocarcinomatous sporadic colorectal cancer in Indian population.

    Directory of Open Access Journals (Sweden)

    Rupal Sinha

    Full Text Available Colorectal cancer (CRC development involves underlying modifications at genetic/epigenetic level. This study evaluated the role of Kras gene mutation and RASSF1A, FHIT and MGMT gene promoter hypermethylation together/independently in sporadic CRC in Indian population and correlation with clinicopathological variables of the disease.One hundred and twenty four consecutive surgically resected tissues (62 tumor and equal number of normal adjacent controls of primary sporadic CRC were included and patient details including demographic characteristics, lifestyle/food or drinking habits, clinical and histopathological profiles were recorded. Polymerase chain reaction - Restriction fragment length polymorphism and direct sequencing for Kras gene mutation and Methylation Specific-PCR for RASSF1A, FHIT and MGMT genes was performed.Kras gene mutation at codon 12 & 13 and methylated RASSF1A, FHIT and MGMT gene was observed in 47%, 19%, 47%, 37% and 47% cases, respectively. Alcohol intake and smoking were significantly associated with presence of Kras mutation (codon 12 and MGMT methylation (p-value <0.049. Tumor stage and metastasis correlated with presence of mutant Kras codon 12 (p-values 0.018, 0.044 and methylated RASSF1A (p-values 0.034, 0.044, FHIT (p-values 0.001, 0.047 and MGMT (p-values 0.018, 0.044 genes. Combinatorial effect of gene mutation/methylation was also observed (p-value <0.025. Overall, tumor stage 3, moderately differentiated tumors, presence of lymphatic invasion and absence of metastasis was more frequently observed in tumors with mutated Kras and/or methylated RASSF1A, FHIT and MGMT genes.Synergistic interrelationship between these genes in sporadic CRC may be used as diagnostic/prognostic markers in assessing the overall pathological status of CRC.

  8. Generation and characterization of mice carrying a conditional allele of the Wwox tumor suppressor gene.

    Directory of Open Access Journals (Sweden)

    John H Ludes-Meyers

    2009-11-01

    Full Text Available WWOX, the gene that spans the second most common human chromosomal fragile site, FRA16D, is inactivated in multiple human cancers and behaves as a suppressor of tumor growth. Since we are interested in understanding WWOX function in both normal and cancer tissues we generated mice harboring a conditional Wwox allele by flanking Exon 1 of the Wwox gene with LoxP sites. Wwox knockout (KO mice were developed by breeding with transgenic mice carrying the Cre-recombinase gene under the control of the adenovirus EIIA promoter. We found that Wwox KO mice suffered from severe metabolic defect(s resulting in growth retardation and all mice died by 3 wk of age. All Wwox KO mice displayed significant hypocapnia suggesting a state of metabolic acidosis. This finding and the known high expression of Wwox in kidney tubules suggest a role for Wwox in acid/base balance. Importantly, Wwox KO mice displayed histopathological and hematological signs of impaired hematopoiesis, leukopenia, and splenic atrophy. Impaired hematopoiesis can also be a contributing factor to metabolic acidosis and death. Hypoglycemia and hypocalcemia was also observed affecting the KO mice. In addition, bone metabolic defects were evident in Wwox KO mice. Bones were smaller and thinner having reduced bone volume as a consequence of a defect in mineralization. No evidence of spontaneous neoplasia was observed in Wwox KO mice. We have generated a new mouse model to inactivate the Wwox tumor suppressor gene conditionally. This will greatly facilitate the functional analysis of Wwox in adult mice and will allow investigating neoplastic transformation in specific target tissues.

  9. Neuroendocrine Tumors in the Stomach, Duodenum, and Pancreas Accompanied by Novel MEN1 Gene Mutation.

    Science.gov (United States)

    Yang, Min A; Lee, Woong Ki; Shin, Hong Shik; Park, Sung Hyun; Kim, Byung Sun; Kim, Ji Woong; Cho, Jin Woong; Yun, So Hee

    2017-03-25

    Multiple endocrine neoplasia type 1 (MEN1) syndrome is a relatively rare disease, characterized by the occurrence of multiple endocrine tumors in the parathyroid and pituitary glands as well as the pancreas. Here, we report a case of MEN1 with neuroendocrine tumors (NETs) in the stomach, duodenum, and pancreas. A 53-year-old man visited our hospital to manage gastric NET. Five years prior to his visit, he had undergone surgery for incidental meningioma. His brother had pancreatic nodules and a history of surgery for adrenal adenoma. His brother's daughter also had pancreatic nodules, but had not undergone surgery. The lesion was treated by endoscopic submucosal dissection and diagnosed as a grade 1 NET. Another small NET was detected in the second duodenal portion, resected by endoscopic submucosal dissection, which was also diagnosed as a grade 1 NET. During evaluation, three nodules were detected in the pancreas, and no evidence of pituitary, parathyroid tumors, or metastasis was observed. After surgery, the pancreatic lesions were diagnosed as NETs, with the same immunohistochemical patterns as those of the stomach and duodenum. Genetic testing was performed, and a heterozygous mutation was detected in the MEN1 gene, which is located on 11q13.

  10. Screening and identification of significant genes related to tumor metastasis and PSMA in prostate cancer using microarray analysis.

    Science.gov (United States)

    Xu, Lin; Wang, Zhu; Li, Xiao-Fei; He, Xia; Guan, Lin-Lin; Tuo, Jiu-Ling; Wang, Yang; Luo, Yanfen; Zhong, Hui-Ling; Qiu, Shao-Peng; Cao, Kai-Yuan

    2013-10-01

    Tumor metastasis is one of the causes for the high mortality rate of prostate cancer (PCa) patients, yet the molecular mechanisms of PCa metastasis are not fully understood. In our previous studies, we found that PSMA suppresses the metastasis of PCa, yet the underlying mechanism remains unknown. To identify the genes related to tumor metastasis possibly regulated by PSMA, we performed tumor metastasis PCR array assay to analyze the differentially expressed tumor metastasis-related genes. Eighty-four tumor metastasis related genes were screened in si-PSMA LNCap cells (PSMA silenced by siRNA)/LNCap cells and in PC-3/LNcap cells, respectively. Expression levels of possible related genes were verified by real-time PCR in 4 prostate cancer cell lines (LNCap, 22RV1, PC-3 and DU145) and in 85 clinical samples (12 normal, 26 benign prostatic hypertrophy and 47 prostate cancer tissues). The results showed that 10 genes (including CDH6 and CXCL12) were upregulated and 4 genes (CCL7, ITGB3, MDM2 and MMP2) were downregulated in the si-PSMA LNCap cells. There were 41 genes significantly upregulated and 15 genes downregulated in PC-3 cells when compared with LNCap cells. Eight common genes were found in both the si-PSMA and PSMA(-) groups. CDH6, MMP3, MTSS1 were further identified as PSMA-related genes in the prostate cancer cell lines and clinical samples, and their expression showed a negative correlation with the stage of prostate cancer (P<0.0001) and PSMA level (P<0.05) in clinical samples, indicating their possible involvement in PSMA-related PCa metastasis regulation. These findings may provide insights into the mechanism involved in the suppression of PCa metastasis by PSMA and its possible interacting proteins, and may provide clues for further exploration of the molecular mechanism of PCa metastasis.

  11. Frequent long-range epigenetic silencing of protocadherin gene clusters on chromosome 5q31 in Wilms' tumor.

    Directory of Open Access Journals (Sweden)

    Anthony R Dallosso

    2009-11-01

    Full Text Available Wilms' tumour (WT is a pediatric tumor of the kidney that arises via failure of the fetal developmental program. The absence of identifiable mutations in the majority of WTs suggests the frequent involvement of epigenetic aberrations in WT. We therefore conducted a genome-wide analysis of promoter hypermethylation in WTs and identified hypermethylation at chromosome 5q31 spanning 800 kilobases (kb and more than 50 genes. The methylated genes all belong to alpha-, beta-, and gamma-protocadherin (PCDH gene clusters (Human Genome Organization nomenclature PCDHA@, PCDHB@, and PCDHG@, respectively. This demonstrates that long-range epigenetic silencing (LRES occurs in developmental tumors as well as in adult tumors. Bisulfite polymerase chain reaction analysis showed that PCDH hypermethylation is a frequent event found in all Wilms' tumor subtypes. Hypermethylation is concordant with reduced PCDH expression in tumors. WT precursor lesions showed no PCDH hypermethylation, suggesting that de novo PCDH hypermethylation occurs during malignant progression. Discrete boundaries of the PCDH domain are delimited by abrupt changes in histone modifications; unmethylated genes flanking the LRES are associated with permissive marks which are absent from methylated genes within the domain. Silenced genes are marked with non-permissive histone 3 lysine 9 dimethylation. Expression analysis of embryonic murine kidney and differentiating rat metanephric mesenchymal cells demonstrates that Pcdh expression is developmentally regulated and that Pcdhg@ genes are expressed in blastemal cells. Importantly, we show that PCDHs negatively regulate canonical Wnt signalling, as short-interfering RNA-induced reduction of PCDHG@ encoded proteins leads to elevated beta-catenin protein, increased beta-catenin/T-cell factor (TCF reporter activity, and induction of Wnt target genes. Conversely, over-expression of PCDHs suppresses beta-catenin/TCF-reporter activity and also inhibits

  12. PMS2 gene mutation results in DNA mismatch repair system failure in a case of adult granulosa cell tumor.

    Science.gov (United States)

    Wang, Wen-Chung; Lee, Ya-Ting; Lai, Yen-Chein

    2017-03-27

    Granulosa cell tumors are rare ovarian malignancies. Their characteristics include unpredictable indolent growth with malignant potential and late recurrence. Approximately 95% are of adult type. Recent molecular studies have characterized the FOXL2 402C > G mutation in adult granulosa cell tumor. Our previous case report showed that unique FOXL2 402C > G mutation and defective DNA mismatch repair system are associated with the development of adult granulosa cell tumor. In this study, the DNA sequences of four genes, MSH2, MLH1, MSH6, and PMS2, in the DNA mismatch repair system were determined via direct sequencing to elucidate the exact mechanism for the development of this granulosa cell tumor. The results showed that two missense germline mutations, T485K and N775L, inactivate the PMS2 gene. The results of this case study indicated that although FOXL2 402C > G mutation determines the development of granulosa cell tumor, PMS2 mutation may be the initial driver of carcinogenesis. Immunohistochemistry-based tumor testing for mismatch repair gene expression may be necessary for granulosa cell tumors to determine their malignant potential or if they are part of Lynch syndrome.

  13. Dual responsive promoters to target therapeutic gene expression to radiation-resistant hypoxic tumor cells

    International Nuclear Information System (INIS)

    Chadderton, Naomi; Cowen, Rachel L.; Sheppard, Freda C.D.; Robinson, Suzanne; Greco, Olga; Scott, Simon D.; Stratford, Ian J.; Patterson, Adam V.; Williams, Kaye J.

    2005-01-01

    Purpose: Tumor hypoxia is unequivocally linked to poor radiotherapy outcome. This study aimed to identify enhancer sequences that respond maximally to a combination of radiation and hypoxia for use in genetic radiotherapy approaches. Methods and materials: The influence of radiation (5 Gy) and hypoxia (1% O 2 ) on reporter-gene expression driven by hypoxia (HRE) and radiation (Egr-1) responsive elements was evaluated in tumor cells grown as monolayers or multicellular spheroids. Hypoxia-inducible factor-1α (HIF-1α) and HIF-2α protein expression was monitored in parallel. Results: Of the sequences tested, an HRE from the phosphoglycerate kinase-1 gene (PGK-18[5+]) was maximally induced in response to hypoxia plus radiation in all 5 cell lines tested. The additional radiation treatment afforded a significant increase in the induction of PGK-18[5+] compared with hypoxia alone in 3 cell lines. HIF-1α/2α were induced by radiation but combined hypoxia/radiation treatment did not yield a further increase. The dual responsive nature of HREs was maintained when spheroids were irradiated after delivery of HRE constructs in a replication-deficient adenovirus. Conclusions: Hypoxia-responsive enhancer element sequences are dually responsive to combined radiation and hypoxic treatment. Their use in genetic radiotherapy in vivo could maximize expression in the most radio-resistant population at the time of radiation and also exploit microenvironmental changes after radiotherapy to yield additional switch-on

  14. The PTEN tumor suppressor gene and its role in lymphoma pathogenesis

    Science.gov (United States)

    Wang, Xiaoxiao; Huang, Huiqiang; Young, Ken H.

    2015-01-01

    The phosphatase and tensin homolog gene PTEN is one of the most frequently mutated tumor suppressor genes in human cancer. Loss of PTEN function occurs in a variety of human cancers via its mutation, deletion, transcriptional silencing, or protein instability. PTEN deficiency in cancer has been associated with advanced disease, chemotherapy resistance, and poor survival. Impaired PTEN function, which antagonizes phosphoinositide 3-kinase (PI3K) signaling, causes the accumulation of phosphatidylinositol (3,4,5)-triphosphate and thereby the suppression of downstream components of the PI3K pathway, including the protein kinase B and mammalian target of rapamycin kinases. In addition to having lipid phosphorylation activity, PTEN has critical roles in the regulation of genomic instability, DNA repair, stem cell self-renewal, cellular senescence, and cell migration. Although PTEN deficiency in solid tumors has been studied extensively, rare studies have investigated PTEN alteration in lymphoid malignancies. However, genomic or epigenomic aberrations of PTEN and dysregulated signaling are likely critical in lymphoma pathogenesis and progression. This review provides updated summary on the role of PTEN deficiency in human cancers, specifically in lymphoid malignancies; the molecular mechanisms of PTEN regulation; and the distinct functions of nuclear PTEN. Therapeutic strategies for rescuing PTEN deficiency in human cancers are proposed. PMID:26655726

  15. Beta4 integrin subunit gene expression correlates with tumor size and nuclear grade in early breast cancer.

    Science.gov (United States)

    Diaz, Leslie K; Cristofanilli, Massimo; Zhou, Xiao; Welch, Kristin L; Smith, Terry L; Yang, Ying; Sneige, Nour; Sahin, Aysegul A; Gilcrease, Michael Z

    2005-09-01

    In vitro data support a role for the alpha6beta4 integrin in tumor cell migration and invasion, particularly in breast carcinoma cells, but clinical data on this potentially important integrin are limited. The beta4 integrin subunit has been shown to cluster with genes characteristic of basal/myoepithelial cells in cDNA microarray analyses of breast cancer, and the subset of breast cancers with increased expression of genes characteristic of basal/myoepithelial cells appears to be particularly aggressive. The purpose of this study was to determine whether alpha6beta4 integrin expression correlates with aggressive clinicopathologic features of breast cancer and whether expression of this integrin has prognostic significance in early breast cancer. We evaluated tumor expression of the beta4 integrin subunit gene in a cohort of patients with early invasive breast carcinoma by in situ hybridization and correlated expression levels with multiple clinicopathologic characteristics. We also evaluated expression of laminin-5 protein, the principal ligand of alpha6beta4, in this patient cohort. Although we observed a slight trend towards decreased disease-free survival for patients whose tumors had high beta4 gene expression and coexpression of laminin-5, this did not reach statistical significance (P=0.11). However, we did observe a correlation between beta4 mRNA expression and both tumor size (P=0.01) and tumor nuclear grade (Plaminin-5 protein expression in early breast cancer, but increased beta4 gene expression in larger tumors and in higher grade tumors does support a potential role for the alpha6beta4 integrin in tumor progression.

  16. Analysis of Relationship between Tumor Necrosis Factor Alpha Gene (G308A Polymorphism) with Preterm Labor.

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    Jafarzadeh, Lobat; Danesh, Azar; Sadeghi, Marzieh; Heybati, Fateme; Hashemzadeh, Morteza

    2013-08-01

    Increased concentrations of tumor necrosis factor alpha (TNF-α) in blood and amniotic fluid are observed in women with preterm delivery (PTD) and TNF-α mutations at -308 position are associated with higher expression of this gene. Therefore, we compared the frequency of G308A transition in the promoter region of TNF-α gene of women and neonates delivered preterm with the normal subjects. This cross-sectional study was performed on 135 mothers who were referred for delivery. According to the gestational age, mothers and their neonates were allocated to the case (preterm, 64 subjects) and control (term, 71 subjects) groups. Using the polymerase chain reaction, restrictive fragment length polymorphism (RFLP), genotyping was performed on both maternal peripheral blood and cord blood samples to determine single nucleotide polymorphism in the promoter region of TNF-α gene at -308. Two mothers in the case group, one mother in the control group and one neonate in the case group had genotyping assays (GA) mutation. All other subjects had normal GG genotype. Frequency of GA mutation was not significantly different between two groups (P = 0.47). There is no significant association between PTD and either maternal or fetal TNF-α -308 polymorphism and frequency ofGAmutation is not significantly increased in mothers and neonates delivered preterm. It means that the presence of this mutation by itself does not modify the overall risk of PTD. Investigations on the combination of various polymorphisms indifferent genes are recommended to achieve more accurate results.

  17. Altered regulation of Prox1-gene-expression in liver tumors

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    Füzesi Laszlo

    2008-04-01

    Full Text Available Abstract Background Prospero-related homeobox 1 (Prox1 transcription factor was described as a tumor-suppressor gene in liver tumors. In contrast, Prox1 knock out in murine embryos drastically reduces proliferation of hepatoblasts. Methods We have studied the expression of Prox1 in normal liver, liver cirrhosis and peritumoral liver samples in comparison to hepatocellular (HCC and cholangiocellular carcinoma (CCC at mRNA, protein and functional levels. Results Prox1 was found in hepatocytes of normal liver, while normal bile duct epithelial cells were negative. However, Prox1+ cells, which co-expressed biliary epithelial makers and showed ductular morphology, could be detected within fibrotic septa of cirrhotic livers, and in both HCC and CCC. Two Prox1 mRNA isoforms (2.9 kb and 7.9 kb were identified with a prevalence of the longer isoform in several HCC samples and the shorter in most CCC samples. Evidence was provided that Myc-associated zinc finger protein (MAZ might significantly contribute to the gene expression of Prox1 in HCC, while neo-expression of Prox1 in CCC remains to be resolved. A point mutation in the prospero domain of Prox1 was found in one HCC sample. Conclusion Our study shows dysregulation of Prox1 in liver cirrhosis, HCC and CCC, such as neo-expression in cells with biliary epithelial phenotype in liver cirrhosis, and in CCC. Altered Prox1 mRNA expression is partly regulated by MAZ, and mutation of the prospero domain in HCC indicates an involvement for Prox1 during tumor progression.

  18. The distribution of BRAF gene fusions in solid tumors and response to targeted therapy.

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    Ross, Jeffrey S; Wang, Kai; Chmielecki, Juliann; Gay, Laurie; Johnson, Adrienne; Chudnovsky, Jacob; Yelensky, Roman; Lipson, Doron; Ali, Siraj M; Elvin, Julia A; Vergilio, Jo-Anne; Roels, Steven; Miller, Vincent A; Nakamura, Brooke N; Gray, Adam; Wong, Michael K; Stephens, Philip J

    2016-02-15

    Although the BRAF V600E base substitution is an approved target for the BRAF inhibitors in melanoma, BRAF gene fusions have not been investigated as anticancer drug targets. In our study, a wide variety of tumors underwent comprehensive genomic profiling for hundreds of known cancer genes using the FoundationOne™ or FoundationOne Heme™ comprehensive genomic profiling assays. BRAF fusions involving the intact in-frame BRAF kinase domain were observed in 55 (0.3%) of 20,573 tumors, across 12 distinct tumor types, including 20 novel BRAF fusions. These comprised 29 unique 5' fusion partners, of which 31% (9) were known and 69% (20) were novel. BRAF fusions included 3% (14/531) of melanomas; 2% (15/701) of gliomas; 1.0% (3/294) of thyroid cancers; 0.3% (3/1,062) pancreatic carcinomas; 0.2% (8/4,013) nonsmall-cell lung cancers and 0.2% (4/2,154) of colorectal cancers, and were enriched in pilocytic (30%) vs. nonpilocytic gliomas (1%; p < 0.0001), Spitzoid (75%) vs. nonSpitzoid melanomas (1%; p = 0.0001), acinar (67%) vs. nonacinar pancreatic cancers (<1%; p < 0.0001) and papillary (3%) vs. nonpapillary thyroid cancers (0%; p < 0.03). Clinical responses to trametinib and sorafenib are presented. In conclusion, BRAF fusions are rare driver alterations in a wide variety of malignant neoplasms, but enriched in Spitzoid melanoma, pilocytic astrocytomas, pancreatic acinar and papillary thyroid cancers. © 2015 The Authors. Published by Wiley Periodicals, Inc. on behalf of UICC.

  19. The Anti-Tumor Effects of Adipose Tissue Mesenchymal Stem Cell Transduced with HSV-Tk Gene on U-87-Driven Brain Tumor.

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    Suely Maymone de Melo

    Full Text Available Glioblastoma (GBM is an infiltrative tumor that is difficult to eradicate. Treating GBM with mesenchymal stem cells (MSCs that have been modified with the HSV-Tk suicide gene has brought significant advances mainly because MSCs are chemoattracted to GBM and kill tumor cells via a bystander effect. To use this strategy, abundantly present adipose-tissue-derived mesenchymal stem cells (AT-MSCs were evaluated for the treatment of GBM in mice. AT-MSCs were prepared using a mechanical protocol to avoid contamination with animal protein and transduced with HSV-Tk via a lentiviral vector. The U-87 glioblastoma cells cultured with AT-MSC-HSV-Tk died in the presence of 25 or 50 μM ganciclovir (GCV. U-87 glioblastoma cells injected into the brains of nude mice generated tumors larger than 3.5 mm2 after 4 weeks, but the injection of AT-MSC-HSV-Tk cells one week after the U-87 injection, combined with GCV treatment, drastically reduced tumors to smaller than 0.5 mm2. Immunohistochemical analysis of the tumors showed the presence of AT-MSC-HSV-Tk cells only within the tumor and its vicinity, but not in other areas of the brain, showing chemoattraction between them. The abundance of AT-MSCs and the easier to obtain them mechanically are strong advantages when compared to using MSCs from other tissues.

  20. Gene expression profiles in primary pancreatic tumors and metastatic lesions of Ela-c-myc transgenic mice

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    Liao Dezhong J

    2008-01-01

    Full Text Available Abstract Background Pancreatic carcinoma usually is a fatal disease with no cure, mainly due to its invasion and metastasis prior to diagnosis. We analyzed the gene expression profiles of paired primary pancreatic tumors and metastatic lesions from Ela-c-myc transgenic mice in order to identify genes that may be involved in the pancreatic cancer progression. Differentially expressed selected genes were verified by semi-quantitative and quantitative RT-PCR. To further evaluate the relevance of some of the selected differentially expressed genes, we investigated their expression pattern in human pancreatic cancer cell lines with high and low metastatic potentials. Results Data indicate that genes involved in posttranscriptional regulation were a major functional category of upregulated genes in both primary pancreatic tumors (PT and liver metastatic lesions (LM compared to normal pancreas (NP. In particular, differential expression for splicing factors, RNA binding/pre-mRNA processing factors and spliceosome related genes were observed, indicating that RNA processing and editing related events may play critical roles in pancreatic tumor development and progression. High expression of insulin growth factor binding protein-1 (Igfbp1 and Serine proteinase inhibitor A1 (Serpina1, and low levels or absence of Wt1 gene expression were exclusive to liver metastatic lesion samples. Conclusion We identified Igfbp1, Serpina1 and Wt1 genes that are likely to be clinically useful biomarkers for prognostic or therapeutic purposes in metastatic pancreatic cancer, particularly in pancreatic cancer where c-Myc is overexpressed.

  1. Tumor-specific expression of shVEGF and suicide gene as a novel strategy for esophageal cancer therapy.

    Science.gov (United States)

    Liu, Ting; Wu, Hai-Jun; Liang, Yu; Liang, Xu-Jun; Huang, Hui-Chao; Zhao, Yan-Zhong; Liao, Qing-Chuan; Chen, Ya-Qi; Leng, Ai-Min; Yuan, Wei-Jian; Zhang, Gui-Ying; Peng, Jie; Chen, Yong-Heng

    2016-06-21

    To develop a potent and safe gene therapy for esophageal cancer. An expression vector carrying fusion suicide gene (yCDglyTK) and shRNA against vascular endothelial growth factor (VEGF) was constructed and delivered into EC9706 esophageal cancer cells by calcium phosphate nanoparticles (CPNP). To achieve tumor selectivity, expression of the fusion suicide gene was driven by a tumor-specific human telomerase reverse transcriptase (hTERT) promoter. The biologic properties and therapeutic efficiency of the vector, in the presence of prodrug 5-fluorocytosine (5-FC), were evaluated in vitro and in vivo. Both in vitro and in vivo testing showed that the expression vector was efficiently introduced by CPNP into tumor cells, leading to cellular expression of yCDglyTK and decreased VEGF level. With exposure to 5-FC, it exhibited strong anti-tumor effects against esophageal cancer. Combination of VEGF shRNA with the fusion suicide gene demonstrated strong anti-tumor activity. The shVEGF-hTERT-yCDglyTK/5-FC system provided a novel approach for esophageal cancer-targeted gene therapy.

  2. Effect of p27 gene combined with Pientzehuang ([characters: see text]) on tumor growth in osteosarcoma-bearing nude mice.

    Science.gov (United States)

    Ren, Shou-song; Yuan, Fang; Liu, Ying-hong; Zhou, Le-tian; Li, Jun

    2015-11-01

    To observe the effect of p27 gene recombinant adenovirus combined with Chinese medicine Pientzehuang ([characters: see text]) on the growth of xenografted human osteosarcoma in nude mice. Tissue transplantation was used to construct the orthotopic model of human osteosarcoma Saos-2 cell in nude mice. Thirty tumor-bearing nude mice were randomly divided into 5 groups with 6 mice in each group: blank control group (model of osteosarcoma), empty vector group (recombinant adeno-associated virus-multiple cloning site), Pientzehuang group, p27 gene group and combined treatment group (p27 gene combined with Pientzehuang). The effect of combined treatment on human osteosarcoma was analyzed through the tumor formation, tumor volume and inhibition rate of tumor growth. The expression of p27 was measured by immunohistochemical staining and Western blot. The orthotopic model of osteosarcoma in nude mice was successfully constructed. The general appearance of tumor-bearing nude mice in Pientzehuang and p27 gene groups was markedly improved compared with the blank control group; and in the combined treatment group it was significantly improved compared with the Pientzehuang and p27 gene groups. The tumor growth in the Pientzehuang and p27 gene groups was significantly inhibited compared with the blank control group P<0.05); while in the combined treatment group it was markedly inhibited compared with the Pientzehuang and p27 gene groups (P<0.05). The rates of tumor growth inhibition were 34.1%, 56.5% and 63.8% in the Pientzehuang, p27 gene and combined treatment groups, respectively. Meanwhile, the protein expression of p27 gene in the p27 gene group was significantly increased compared with the blank control group (P<0.05); and it was significantly increased in the combined treatment group compared with the p27 gene and Pientzehuang groups (P<0.05). p27 gene introduced by adenovirus combined with Pientzehuang can inhibit the growth of human osteosarcoma cell Saos-2 in nude mice.

  3. Integrated bioinformatic analysis unveils significant genes and pathways in the pathogenesis of supratentorial primitive neuroectodermal tumor

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    Wang G

    2018-04-01

    Full Text Available Guang-Yu Wang,1,* Ling Li,2,* Bo Liu,1 Xiao Han,1 Chun-Hua Wang,1 Ji-Wen Wang3 1Department of Neurosurgery, 2Department of Pediatrics, Qilu Children’s Hospital of Shandong University, Jinan, Shandong, 3Department of Neurology, Shanghai Children’s Medical Center, Shanghai Jiaotong University School of Medicine, Pudong New District, Shanghai, People’s Republic of China *These authors contributed equally to this work Purpose: This study aimed to explore significant genes and pathways involved in the pathogenesis of supratentorial primitive neuroectodermal tumor (sPNET. Materials and methods: Gene expression profile of GSE14295 was downloaded from publicly available Gene Expression Omnibus (GEO database. Differentially expressed genes (DEGs were screened out in primary sPNET samples compared with normal fetal and adult brain reference samples (sPNET vs fetal brain and sPNET vs adult brain. Pathway enrichment analysis of these DEGs was conducted, followed by protein–protein interaction (PPI network construction and significant module selection. Additionally, transcription factors (TFs regulating the common DEGs in the two comparison groups were identified, and the regulatory network was constructed. Results: In total, 526 DEGs (99 up- and 427 downregulated in sPNET vs fetal brain and 815 DEGs (200 up- and 615 downregulated in sPNET vs adult brain were identified. DEGs in sPNET vs fetal brain and sPNET vs adult brain were associated with calcium signaling pathway, cell cycle, and p53 signaling pathway. CDK1, CDC20, BUB1B, and BUB1 were hub nodes in the PPI networks of DEGs in sPNET vs fetal brain and sPNET vs adult brain. Significant modules were extracted from the PPI networks. In addition, 64 upregulated and 200 downregulated overlapping DEGs were identified in both sPNET vs fetal brain and sPNET vs adult brain. The genes involved in the regulatory network upon overlapping DEGs and the TFs were correlated with calcium signaling pathway

  4. Rare frequency of gene variation and survival analysis in thymic epithelial tumors

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    Song Z

    2016-10-01

    Full Text Available Zhengbo Song,1,2,* Xinmin Yu,1,2,* Yiping Zhang1,2 1Department of Medical Oncology, Zhejiang Cancer Hospital, 2Key Laboratory Diagnosis and Treatment Technology on Thoracic Oncology, Zhejiang Province, Hangzhou, People’s Republic of China *These authors contributed equally to this work Objective: Thymic epithelial tumor (TET is a rare mediastinal neoplasm and little is known about its genetic variability and prognostic factors. This study investigated the genetic variability and prognostic factors of TET. Patients and methods: We sequenced 22 cancer-related hotspot genes in TET tissues and matched normal tissues using Ampliseq Ion Torrent next-generation technology. Overall survival was evaluated using Kaplan–Meier methods and compared with log-rank tests. Results: A histological analysis of 52 patients with a median age of 52 years showed 15 patients (28.8% with thymic carcinoma, five with type A thymoma (9.6%, eight with type AB (15.4%, six with type B1 (11.5%, nine with type B2 (17.3%, and nine with type B3 thymoma (17.3%. Three gene mutations were identified, including two with PIK3CA mutation and one with EGFR mutation. The three patients with mutant genes included two cases of thymoma (one with EGFR and the other with PIK3CA mutation in addition to a case of thymic carcinoma (PIK3CA mutation. The 5-year survival rates were 77.7% in all patients. The 5-year survival rates were 93.3%, 90.0%, 76.9%, and 22.9% corresponding to Masaoka stages I, II, III, and IV (P<0.001. The 5-year survival rates were 100%, 100%, 83.3%, 88.9%, 65.6%, and 60.9% in the histological subtypes of A, AB, B1, B2, and B3 thymomas, and thymic carcinoma, respectively (P=0.012. Conclusion: Hotspot gene mutations are rare in TET. PIK3CA and EGFR mutations represent candidate driver genes and treatment targets in TET. Masaoka stage and histological subtypes predict the survival of TET. Keywords: thymic epithelial tumors, gene mutation, prognosis

  5. Frequent PIK3CA Mutations in Colorectal and Endometrial Tumors With 2 or More Somatic Mutations in Mismatch Repair Genes.

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    Cohen, Stacey A; Turner, Emily H; Beightol, Mallory B; Jacobson, Angela; Gooley, Ted A; Salipante, Stephen J; Haraldsdottir, Sigurdis; Smith, Christina; Scroggins, Sheena; Tait, Jonathan F; Grady, William M; Lin, Edward H; Cohn, David E; Goodfellow, Paul J; Arnold, Mark W; de la Chapelle, Albert; Pearlman, Rachel; Hampel, Heather; Pritchard, Colin C

    2016-09-01

    Some colorectal and endometrial tumors with microsatellite instability not attributable to MLH1 hypermethylation or germline mutations contain 2 or more somatic mutations in genes encoding mismatch repair (MMR) proteins. We sought to define the molecular phenotype of this newly recognized tumor subtype. From 2 prospective studies of the efficacy of screening for Lynch syndrome, we identified patients with colorectal and endometrial tumors who had 2 or more somatic (but not germline) mutations in genes encoding MMR proteins (double somatic). We determined the frequencies of tumor mutations in PIK3CA, BRAF, KRAS, NRAS, and PTEN by targeted next-generation sequencing and used logistic-regression models to compare them with those from patients with Lynch syndrome, MLH1-hypermethylated, or microsatellite-stable tumors. We validated our findings using independent data sets from The Cancer Genome Atlas. Among colorectal cancer cases, we found that 14 of 21 (67%) patients with double somatic tumors also had PIK3CA mutations, compared with 4 of 18 (22%) tumors from patients with Lynch syndrome, 2 of 10 (20%) tumors with MLH1 hypermethylation, and 12 of 78 (15%) tumors with microsatellite stability (P < .0001 for patients with double somatic tumors vs other subgroups). Mutations in PIK3CA were detected in all 13 patients with double somatic endometrial cancers (P = .04 compared with other subgroups). We did not detect BRAF mutations in patients with double somatic colorectal tumors or Lynch syndrome. We found highly similar results in a validation cohort from The Cancer Genome Atlas (113 patients with colorectal tumors, 178 endometrial tumors); 100% of double somatic cases had a somatic mutation in PIK3CA (P < .0001 compared with other subgroups). Most patients with colorectal or endometrial tumors with 2 or more somatic (but not germline) mutations in MMR proteins also have mutations in PIK3CA; mutations in PIK3CA are detected at substantially higher frequencies in these

  6. Targeted gene delivery in tumor xenografts by the combination of ultrasound-targeted microbubble destruction and polyethylenimine to inhibit survivin gene expression and induce apoptosis

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    Qiu Ri-Xiang

    2010-11-01

    Full Text Available Abstract Background Noninvasive and tissue-specific technologies of gene transfection would be valuable in clinical gene therapy. This present study was designed to determine whether it could enhance gene transfection in vivo by the combination of ultrasound-targeted microbubble destruction (UTMD with polyethylenimine (PEI in tumor xenografts, and illuminate the effects of gene silencing and apoptosis induction with short hairpin RNA (shRNA interference therapy targeting human survivin by this novel technique. Methods Two different expression vectors (pCMV-LUC and pSIREN were incubated with PEI to prepare cationic complexes (PEI/DNA and confirmed by the gel retardation assay. Human cervical carcinoma (Hela tumors were planted subcutaneously in both flanks of nude mice. Tumor-bearing mice were administered by tail vein with PBS, plasmid, plasmid and SonoVue microbubble, PEI/DNA and SonoVue microbubble. One tumor was exposed to ultrasound irradiation, while the other served as control. The feasibility of targeted delivery and tissue specificity facilitated by UTMD and PEI were investigated. Moreover, immunohistochemistry analyses about gene silencing and apoptosis induction were detected. Results Electrophoresis experiment revealed that PEI could condense DNA efficiently. The application of UTMD significantly increases the tissue transfection. Both expression vectors showed that gene expressions were present in all sections of tumors that received ultrasound exposure but not in control tumors. More importantly, the increases in transgene expression were related to UTMD with the presence of PEI significantly. Silencing of the survivin gene could induce apoptosis effectively by downregulating survivin and bcl-2 expression, also cause up-regulation of bax and caspase-3 expression. Conclusions This noninvasive, novel combination of UTMD with PEI could enhance targeted gene delivery and gene expression in tumor xenografts at intravenous administration

  7. Detection of transformed cells in crown gall tumors using the GUS reporter gene and correlation of GUS stained cells with T-DNA gene activity

    International Nuclear Information System (INIS)

    Black, R.C.; Labriola, J.; Binns, A.N.

    1990-01-01

    Crown gall tumors are a mixture of transformed hormone producing cells and normal cells. Until now it has not been possible to directly visualize these cell types in situ. We have constructed strains of Agrobacterium tumefaciens that carry the 35S-β-glucuronidase (GUS) reporter gene in either wild type or mutant Ti plasmids. Using histochemical staining for GUS activity, blue (GUS positive) sectors are observed in tumor sections. In order to demonstrate that the blue sectors actually represent cells expressing other T-DNA genes, we have looked for T-DNA gene encoded enzyme activity in the stained and unstained sectors. The blue sectors accumulate octopine (a product of the octopine synthase gene on the T-DNA) while the white (GUS negative) sectors do not. We conclude that the use of the GUS reporter gene provides a sensitive and reliable method for visualizing transformation events in plant tissues. A comparison of the proportion of transformed and nontransformed cells in wild type tumors vs. tumors deficient in auxin or cytokinin encoding genes will be discussed

  8. Tissue-wide expression profiling using cDNA subtraction and microarrays to identify tumor-specific genes.

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    Amatschek, Stefan; Koenig, Ulrich; Auer, Herbert; Steinlein, Peter; Pacher, Margit; Gruenfelder, Agnes; Dekan, Gerhard; Vogl, Sonja; Kubista, Ernst; Heider, Karl-Heinz; Stratowa, Christian; Schreiber, Martin; Sommergruber, Wolfgang

    2004-02-01

    With the objective of discovering novel putative intervention sites for anticancer therapy, we compared transcriptional profiles of breast cancer, lung squamous cell cancer (LSCC), lung adenocarcinoma (LAC), and renal cell cancer (RCC). Each of these tumor types still needs improvement in medical treatment. Our intention was to search for genes not only highly expressed in the majority of patient samples but which also exhibit very low or even absence of expression in a comprehensive panel of 16 critical (vital) normal tissues. To achieve this goal, we combined two powerful technologies, PCR-based cDNA subtraction and cDNA microarrays. Seven subtractive libraries consisting of approximately 9250 clones were established and enriched for tumor-specific transcripts. These clones, together with approximately 1750 additional tumor-relevant genes, were used for cDNA microarray preparation. Hybridizations were performed using a pool of 16 critical normal tissues as a reference in all experiments. In total, we analyzed 20 samples of breast cancer, 11 of LSCC, 11 of LAC, and 8 of RCC. To select for genes with low or even no expression in normal tissues, expression profiles of 22 different normal tissues were additionally analyzed. Importantly, this tissue-wide expression profiling allowed us to eliminate genes, which exhibit also high expression in normal tissues. Similarly, expression signatures of genes, which are derived from infiltrating cells of the immune system, were eliminated as well. Cluster analysis resulted in the identification of 527 expressed sequence tags specifically up-regulated in these tumors. Gene-wise hierarchical clustering of these clones clearly separated the different tumor types with RCC exhibiting the most homogeneous and LAC the most diverse expression profile. In addition to already known tumor-associated genes, the majority of identified genes have not yet been brought into context with tumorigenesis such as genes involved in bone matrix

  9. Comparative analyses of gene copy number and mRNA expression in GBM tumors and GBM xenografts

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    Hodgson, J. Graeme; Yeh, Ru-Fang; Ray, Amrita; Wang, Nicholas J.; Smirnov, Ivan; Yu, Mamie; Hariono, Sujatmi; Silber, Joachim; Feiler, Heidi S.; Gray, Joe W.; Spellman, Paul T.; Vandenberg, Scott R.; Berger, Mitchel S.; James, C. David

    2009-04-03

    Development of model systems that recapitulate the molecular heterogeneity observed among glioblastoma multiforme (GBM) tumors will expedite the testing of targeted molecular therapeutic strategies for GBM treatment. In this study, we profiled DNA copy number and mRNA expression in 21 independent GBM tumor lines maintained as subcutaneous xenografts (GBMX), and compared GBMX molecular signatures to those observed in GBM clinical specimens derived from the Cancer Genome Atlas (TCGA). The predominant copy number signature in both tumor groups was defined by chromosome-7 gain/chromosome-10 loss, a poor-prognosis genetic signature. We also observed, at frequencies similar to that detected in TCGA GBM tumors, genomic amplification and overexpression of known GBM oncogenes, such as EGFR, MDM2, CDK6, and MYCN, and novel genes, including NUP107, SLC35E3, MMP1, MMP13, and DDX1. The transcriptional signature of GBMX tumors, which was stable over multiple subcutaneous passages, was defined by overexpression of genes involved in M phase, DNA replication, and chromosome organization (MRC) and was highly similar to the poor-prognosis mitosis and cell-cycle module (MCM) in GBM. Assessment of gene expression in TCGA-derived GBMs revealed overexpression of MRC cancer genes AURKB, BIRC5, CCNB1, CCNB2, CDC2, CDK2, and FOXM1, which form a transcriptional network important for G2/M progression and/or checkpoint activation. Our study supports propagation of GBM tumors as subcutaneous xenografts as a useful approach for sustaining key molecular characteristics of patient tumors, and highlights therapeutic opportunities conferred by this GBMX tumor panel for testing targeted therapeutic strategies for GBM treatment.

  10. Gene expression profiles of cell adhesion molecules, matrix metalloproteinases and their tissue inhibitors in canine oral tumors.

    Science.gov (United States)

    Pisamai, Sirinun; Rungsipipat, Anudep; Kalpravidh, Chanin; Suriyaphol, Gunnaporn

    2017-08-01

    Perturbation of cell adhesion can be essential for tumor cell invasion and metastasis, but the current knowledge on the gene expression of molecules that mediate cell adhesion in canine oral tumors is limited. The present study aimed to investigate changes in the gene expression of cell adhesion molecules (E-cadherin or CDH1, syndecan 1 or SDC1, NECTIN2 and NECTIN4), matrix metalloproteinases (MMPs) and their tissue inhibitors (TIMPs), in canine oral tumors, including benign tumors, oral melanoma (OM) and non-tonsillar oral squamous cell carcinoma (OSCC), by quantitative real-time reverse transcription PCR. When compared with the normal gingival controls, decreased CDH1, SDC1 and NECTIN4 expression levels were observed in OSCC and OM, reflecting a possible role as cell adhesion molecules and tumor suppressors in canine oral cancers in contrast to the upregulation of MMP2 expression. Downregulated MMP7 was specifically revealed in the OM group. In the late-stage OM, the positive correlation of MMP7 and CDH1 expression was noticed as well as that of SDC1 and NECTIN4. Enhanced TIMP1 expression was shown in all tumor groups with prominent expression in the benign tumors and the early-stage OM. MMP14 expression was notable in the early-stage OM. Higher MMP9 and TIMP1 expression was observed in the acanthomatous ameloblastoma. In conclusion, this study revealed that the altered expression of cell adhesion molecules, MMP7 and MMP2 was correlated with clinicopathologic features in canine oral cancers whereas TIMP1 and MMP14 expression was probably associated with early-stage tumors; therefore, these genes might serve as molecular markers for canine oral tumors. Copyright © 2017 Elsevier Ltd. All rights reserved.

  11. Radiosensitivity and gene expression of human lung cancer cells dividing in nude tumor before (anoxic) and after vascular induction

    International Nuclear Information System (INIS)

    Miyamoto, Tadaaki; Baba, Masayuki; Sugawara, Toshiyuki; Yashiro, Tomoyasu; Saegusa, Kumiko; Furuno, Aki; Michikawa, Yuichi; Imai, Takashi

    2005-01-01

    Using cultured and nude mouse tumor cell (IA) derived frome a human lung cancer, we studied their radiosensitivity by focusing attention on the dynamics of tumor clonogens. The movement of clonogens in the regrowing IA tumor after X rays irradiation can be divided into three phases: first,: the early and rapid survival recovery (PLD repair) phase, second, the delay phase involving a certain lag in survival change, and third, the repopulation phase consisting of two stagea. Now we compare with the dynamics of tumor clonogens before or after exposure to X rays and carbon-ion beams. PLD repair was not observed in a carbon-ion beam. In relation to radiosensitivity and repair mechanism, we studied the gene expression of the cultured cell and nude tumor with a microarray method using 22K custom oligoallele. (author)

  12. Systematic Analysis of Time-Series Gene Expression Data on Tumor Cell-Selective Apoptotic Responses to HDAC Inhibitors

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    Yun-feng Qi

    2014-01-01

    Full Text Available SAHA (suberoylanilide hydroxamic acid or vorinostat is the first nonselective histone deacetylase (HDAC inhibitor approved by the US Food and Drug Administration (FDA. SAHA affects histone acetylation in chromatin and a variety of nonhistone substrates, thus influencing many cellular processes. In particularly, SAHA induces selective apoptosis of tumor cells, although the mechanism is not well understood. A series of microarray experiments was recently conducted to investigate tumor cell-selective proapoptotic transcriptional responses induced by SAHA. Based on that gene expression time series, we propose a novel framework for detailed analysis of the mechanism of tumor cell apoptosis selectively induced by SAHA. Our analyses indicated that SAHA selectively disrupted the DNA damage response, cell cycle, p53 expression, and mitochondrial integrity of tumor samples to induce selective tumor cell apoptosis. Our results suggest a possible regulation network. Our research extends the existing research.

  13. Tumor suppressor gene P53 in fish species as a target for genotoxic effects monitoring

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    Kusser, W.C.; Brand, D.; Glickman, B.W. [Univ. of Victoria, British Columbia (Canada); Cretney, W.

    1995-12-31

    Analysis of environmentally induced molecular changes in DNA from fish was initiated with a study of tumor suppressor gene p53. This gene was chosen because of the high number of documented mutations in p53 from humans and their relevance in tumorigenesis. Bottom-feeding flatfish (e.g. English sole, Pleuronectes vetulus) and members of the salmonid family (e.g. rainbow trout, Oncorhynchus mykiss and chinook salmon, O. tschaaytsha) were chosen, because they are widespread and of commercial and recreational importance. The studies include the use of histopathological, biochemical, and molecular genetic tools in aquatic systems. The authors are currently examining the deposition of DNA damage and mutation in the p53 gene in fish. Parallel histopathology of liver showed idiopathic liver lesions that were strongly dependent on location of capture (0.01 < p(X{sup 2} 0.05, 2 > 6.89) < 0.025) with a prevalence of 30% for fish collected from the vicinity of pulp mills. To assess DNA damage and mutation analysis, DNA was extracted from fish liver. Polymerase chain reaction (PCR) and DNA sequencing of the p53 gene was performed for rainbow trout, chinook and sockeye salmon, O. nerka. Southern blotting with a labeled p53 probe from rainbow trout was performed using genomic DNA from various teleost fish species. The presence of p53 could be shown in all fish species examined, including salmonids and sentinel species for environmental monitoring like English sole and white sucker (Catostomus commersom). To correlate histopathology with molecular analysis the authors initiated the determination of DNA damage, DNA adducts and mutations in the p53 gene (conserved exons 5 to 9).

  14. Gene expression in skin tumors induced in hairless mice by chronic exposure to ultraviolet B irradiation

    International Nuclear Information System (INIS)

    Sato, Hiromi; Tanaka, Misao; Kobayashi, Shizuko; Suzuki, Junko S.; Ogiso, Manabu; Tohyama, Chiharu

    1997-01-01

    We investigated the expressions of c-Ha-ras, c-jun, c-fos, c-myc genes and p53 protein in the development of skin tumours induced by chronic exposure to UVB without a photosensitizer using hairless mice. When mice were exposed to UVB at a dose of 2 kJ/m 2 three times a week, increased c-Ha-ras and c-myc transcripts were detected after only 5 weeks of exposure, while no tumour appeared on the exposed skin. The increase in gene expression continued until 25 weeks, when tumours, identified pathologically as mainly squamous cell carcinomas (SCC), developed in the dorsal skin. In these SCC, overexpression of c-fos mRNA was also observed along with the increases in c-Ha-ras and c-myc. A single dose of UVB (2 kJ/m 2 ) applied to the backs of hairless mice transiently induced overexpression of the early event genes c-fos, c-jun and c-myc, but not c-Ha-ras, in the exposed area of skin. Accumulation of p53 protein was determined by Western blotting analysis of immunohistochemistry using monoclonal antibodies PAb 240 or 246, which recognize mutant or wide type, respectively. In the SCC, a mutant p53 protein accumulated in the cytoplasm and nucleus. After single-dose irradiation, the increased wild-type p53 protein was observed in the nuclei of epidermal cells. The present results suggest that overexpression of the c-fos, c-myc and c-Ha-ras genes, and the mutational changes in p53 protein might be associated with skin photocarcinogenesis. Moreover, overexpression of the c-Ha-ras and c-myc genes might be an early event in the development of UVB-induced skin tumors in mice. (author)

  15. Tumor growth reduction is regulated at the gene level in Walker 256 tumor-bearing rats supplemented with fish oil rich in EPA and DHA

    Energy Technology Data Exchange (ETDEWEB)

    Borghetti, G.; Yamazaki, R.K.; Coelho, I.; Pequito, D.C.T.; Schiessel, D.L.; Kryczyk, M.; Mamus, R.; Naliwaiko, K.; Fernandes, L.C. [Departamento de Fisiologia, Setor de Ciências Biológicas, Universidade Federal do Paraná, Curitiba, PR (Brazil)

    2013-08-23

    We investigated the effect of fish oil (FO) supplementation on tumor growth, cyclooxygenase 2 (COX-2), peroxisome proliferator-activated receptor gamma (PPARγ), and RelA gene and protein expression in Walker 256 tumor-bearing rats. Male Wistar rats (70 days old) were fed with regular chow (group W) or chow supplemented with 1 g/kg body weight FO daily (group WFO) until they reached 100 days of age. Both groups were then inoculated with a suspension of Walker 256 ascitic tumor cells (3×10{sup 7} cells/mL). After 14 days the rats were killed, total RNA was isolated from the tumor tissue, and relative mRNA expression was measured using the 2{sup -ΔΔCT} method. FO significantly decreased tumor growth (W=13.18±1.58 vs WFO=5.40±0.88 g, P<0.05). FO supplementation also resulted in a significant decrease in COX-2 (W=100.1±1.62 vs WFO=59.39±5.53, P<0.001) and PPARγ (W=100.4±1.04 vs WFO=88.22±1.46, P<0.05) protein expression. Relative mRNA expression was W=1.06±0.022 vs WFO=0.31±0.04 (P<0.001) for COX-2, W=1.08±0.02 vs WFO=0.52±0.08 (P<0.001) for PPARγ, and W=1.04±0.02 vs WFO=0.82±0.04 (P<0.05) for RelA. FO reduced tumor growth by attenuating inflammatory gene expression associated with carcinogenesis.

  16. Gene expression, single nucleotide variant and fusion transcript discovery in archival material from breast tumors.

    Directory of Open Access Journals (Sweden)

    Nadine Norton

    Full Text Available Advantages of RNA-Seq over array based platforms are quantitative gene expression and discovery of expressed single nucleotide variants (eSNVs and fusion transcripts from a single platform, but the sensitivity for each of these characteristics is unknown. We measured gene expression in a set of manually degraded RNAs, nine pairs of matched fresh-frozen, and FFPE RNA isolated from breast tumor with the hybridization based, NanoString nCounter (226 gene panel and with whole transcriptome RNA-Seq using RiboZeroGold ScriptSeq V2 library preparation kits. We performed correlation analyses of gene expression between samples and across platforms. We then specifically assessed whole transcriptome expression of lincRNA and discovery of eSNVs and fusion transcripts in the FFPE RNA-Seq data. For gene expression in the manually degraded samples, we observed Pearson correlations of >0.94 and >0.80 with NanoString and ScriptSeq protocols, respectively. Gene expression data for matched fresh-frozen and FFPE samples yielded mean Pearson correlations of 0.874 and 0.783 for NanoString (226 genes and ScriptSeq whole transcriptome protocols respectively, p<2x10(-16. Specifically for lincRNAs, we observed superb Pearson correlation (0.988 between matched fresh-frozen and FFPE pairs. FFPE samples across NanoString and RNA-Seq platforms gave a mean Pearson correlation of 0.838. In FFPE libraries, we detected 53.4% of high confidence SNVs and 24% of high confidence fusion transcripts. Sensitivity of fusion transcript detection was not overcome by an increase in depth of sequencing up to 3-fold (increase from ~56 to ~159 million reads. Both NanoString and ScriptSeq RNA-Seq technologies yield reliable gene expression data for degraded and FFPE material. The high degree of correlation between NanoString and RNA-Seq platforms suggests discovery based whole transcriptome studies from FFPE material will produce reliable expression data. The RiboZeroGold ScriptSeq protocol

  17. [Testing of mutations in BRCA1 and BRCA2 genes in tumor tissues - possibilities and limitations].

    Science.gov (United States)

    Vošmiková, Hana; Ryška, Aleš; Sieglová, Kateřina; Laco, Jan

    2016-01-01

    Development of targeted cancer therapy is accompanied by a search for markers allowing prediction of response to the particular treatment. Recently, the interest is focused, among other neoplasms, also on the therapy of ovarian cancer using new inhibitors of poly (ADP-ribose) polymerase (PARP) proteins, nuclear enzymes involved in the repair of single-stranded DNA breaks. The greatest benefit from the administration of PARP inhibitors have patients with a deleterious or potentially deleterious germ-line or somatic mutation of BRCA1 or BRCA2, two genes responsible for repair of double stranded DNA breaks. There has been described a wide spectrum of mutations of BRCA 1/2, from point substitutions to large deletions, including sometimes even several exons of the gene.Unlike the testing of germ-line mutations provided for many years by the medical geneticists, somatic mutations in the tumor tissue have not been routinely tested so far. Detection of BRCA1/2 mutations in the tumor is significantly different from testing of germ-line mutations. In comparison with the analysis of DNA isolated from blood samples, testing of DNA isolated from the FFPE tissue encounters challenges based on heterogeneous representation of tumor cells in the tissue samples, on the presence of multiple neoplastic clones and on the infiltration of tissue by the non-neoplastic elements, as well as difficulties caused by variable proportion of apoptotic and necrotic cells deteriorating the overall quality of isolated DNA.Regarding the testing methods, NGS appears to be the optimal choice because of its complexity, speed of implementation into routine diagnostics as well as sensitivity for detection of a BRCA 1/2 mutations. When introduced into everyday laboratory practice, the functioning quality control system is of utmost importance. Provided there is a high probability of detection of the so far unreported variations in BRCA 1/2 genes, an introduction of a shared database of somatic variants

  18. Functional heterogeneity of cancer-associated fibroblasts from human colon tumors shows specific prognostic gene expression signature.

    Science.gov (United States)

    Herrera, Mercedes; Islam, Abul B M M K; Herrera, Alberto; Martín, Paloma; García, Vanesa; Silva, Javier; Garcia, Jose M; Salas, Clara; Casal, Ignacio; de Herreros, Antonio García; Bonilla, Félix; Peña, Cristina

    2013-11-01

    Cancer-associated fibroblasts (CAF) actively participate in reciprocal communication with tumor cells and with other cell types in the microenvironment, contributing to a tumor-permissive neighborhood and promoting tumor progression. The aim of this study is the characterization of how CAFs from primary human colon tumors promote migration of colon cancer cells. Primary CAF cultures from 15 primary human colon tumors were established. Their enrichment in CAFs was evaluated by the expression of various epithelial and myofibroblast specific markers. Coculture assays of primary CAFs with different colon tumor cells were performed to evaluate promigratory CAF-derived effects on cancer cells. Gene expression profiles were developed to further investigate CAF characteristics. Coculture assays showed significant differences in fibroblast-derived paracrine promigratory effects on cancer cells. Moreover, the association between CAFs' promigratory effects on cancer cells and classic fibroblast activation or stemness markers was observed. CAF gene expression profiles were analyzed by microarray to identify deregulated genes in different promigratory CAFs. The gene expression signature, derived from the most protumorogenic CAFs, was identified. Interestingly, this "CAF signature" showed a remarkable prognostic value for the clinical outcome of patients with colon cancer. Moreover, this prognostic value was validated in an independent series of 142 patients with colon cancer, by quantitative real-time PCR (qRT-PCR), with a set of four genes included in the "CAF signature." In summary, these studies show for the first time the heterogeneity of primary CAFs' effect on colon cancer cell migration. A CAF gene expression signature able to classify patients with colon cancer into high- and low-risk groups was identified.

  19. Molecular analysis of BRCA1 and BRCA2 genes by next generation sequencing and ultrastructural aspects of breast tumor tissue.

    Science.gov (United States)

    Mihalcea, Corina Elena; Moroşanu, Ana Maria; Murăraşu, Daniela; Puiu, Liliana; Cinca, Sabin Aurel; Voinea, Silviu Cristian; Mirancea, Nicolae

    2017-01-01

    In this paper, we focus our interest on the dynamics alterations of the tumor-stroma interface at the ultrastructural level and to detect BRCA1 and BRCA2 mutations using next generation sequencing (NGS) of breast tumor tissue. Electron microscopic investigation revealed some peculiar infrastructural alterations of the tumor cells per se as well as of the tumor-stroma interface: invadopodia, shedding microvesicles, altered morphology and reduced number of telocytes, different abnormalities of the microvasculature. Tumor suppressor genes BRCA1 and BRCA2 are the genes with most hereditary predisposition to breast and ovarian cancer. An early identification of mutation within these genes is essential for determining classification and therapeutic approach to patients. Genetic tests used to determine mutations in BRCA1 and BRCA2 genes are laborious analysis methods which include, among others, NGS. We analyzed a total of eight samples, in which genomic DNA was amplified using Ion AmpliSeq panel BRCA1 and BRCA2. DNA libraries were created, amplified and sequenced with Ion Torrent Personal Genome Machine. The bio-information data obtained allow us to detect all known pathogenic mutation and uncertain polymorphisms.

  20. Anti-tumor effects of Egr-IFN γ gene therapy combined with 125I-UdR radionuclide therapy

    International Nuclear Information System (INIS)

    Zhao Jingguo; Ni Yanjun; Song Xiangfu; Li Yanyi; Yang Wei; Sun Ting; Ma Qingjie; Gao Fengtong

    2008-01-01

    Objective: To explore the anti-tumor effects of Egr-IFNγ gene therapy combined with 125 I-UdR radionuclide therapy in mice bearing H22 hepatocarcinoma and its mechanism. Methods: The recombinant plasmid pcDNAEgr-IFNγ mixed with liposome was injected into tumor. 48 h later, 370 kBq 125 I-UdR was injected into tumor. The tumor growth rates at different times were observed. After 3 d gene-radionuclide therapy, the concentration of IFNγ in cytoplasm of H22 cells and cytotoxic activities of splenic CTL of the mice in different groups were examined. Results: The tumor growth rates of pcDNAEgr-IFNγ + 125 I-UdR group were obviously lower than those of control group, 125 I-UdR group and pcDNAEgr-1 + 125 I-UdR group 6-15 d after gene-radionuclide therapy. IFNγ protein was found in cytoplasm of H22 cells in pcDNAEgr-IFNγ + 125 I-UdR group after 3 d gene-radionuclide therapy. Cytotoxic activity of splenic CTL in pcDNAEgr-IFNγ + 125 I-UdR group was significantly higher than that in the other groups (P 125 I-UdR radionuclide therapy are better than those of 125 I-UdR therapy. (authors)

  1. Identification of genes highly downregulated in pancreatic cancer through a meta-analysis of microarray datasets: implications for discovery of novel tumor-suppressor genes and therapeutic targets.

    Science.gov (United States)

    Goonesekere, Nalin C W; Andersen, Wyatt; Smith, Alex; Wang, Xiaosheng

    2018-02-01

    The lack of specific symptoms at early tumor stages, together with a high biological aggressiveness of the tumor contribute to the high mortality rate for pancreatic cancer (PC), which has a 5-year survival rate of about 7%. Recent failures of targeted therapies inhibiting kinase activity in clinical trials have highlighted the need for new approaches towards combating this deadly disease. In this study, we have identified genes that are significantly downregulated in PC, through a meta-analysis of large number of microarray datasets. We have used qRT-PCR to confirm the downregulation of selected genes in a panel of PC cell lines. This study has yielded several novel candidate tumor-suppressor genes (TSGs) including GNMT, CEL, PLA2G1B and SERPINI2. We highlight the role of GNMT, a methyl transferase associated with the methylation potential of the cell, and CEL, a lipase, as potential therapeutic targets. We have uncovered genetic links to risk factors associated with PC such as smoking and obesity. Genes important for patient survival and prognosis are also discussed, and we confirm the dysregulation of metabolic pathways previously observed in PC. While many of the genes downregulated in our dataset are associated with protein products normally produced by the pancreas for excretion, we have uncovered some genes whose downregulation appear to play a more causal role in PC. These genes will assist in providing a better understanding of the disease etiology of PC, and in the search for new therapeutic targets and biomarkers.

  2. Regulation of the insulin-like developmental pathway of Caenorhabditis elegans by a homolog of the PTEN tumor suppressor gene

    OpenAIRE

    Gil, Elad B.; Malone Link, Elizabeth; Liu, Leo X.; Johnson, Carl D.; Lees, Jacqueline A.

    1999-01-01

    The human PTEN tumor suppressor gene is mutated in a wide variety of sporadic tumors. To determine the function of PTEN in vivo we have studied a PTEN homolog in Caenorhabditis elegans. We have generated a strong loss-of-function allele of the PTEN homolog and shown that the deficient strain is unable to enter dauer diapause. An insulin-like phosphatidylinositol 3-OH kinase (PI3′K) signaling pathway regulates dauer-stage entry. Mutations in either the daf-2 insulin receptor-like (IRL) gene or...

  3. Expression of tumor necrosis factor-alpha-mediated genes predicts recurrence-free survival in lung cancer.

    Directory of Open Access Journals (Sweden)

    Baohua Wang

    Full Text Available In this study, we conducted a meta-analysis on high-throughput gene expression data to identify TNF-α-mediated genes implicated in lung cancer. We first investigated the gene expression profiles of two independent TNF-α/TNFR KO murine models. The EGF receptor signaling pathway was the top pathway associated with genes mediated by TNF-α. After matching the TNF-α-mediated mouse genes to their human orthologs, we compared the expression patterns of the TNF-α-mediated genes in normal and tumor lung tissues obtained from humans. Based on the TNF-α-mediated genes that were dysregulated in lung tumors, we developed a prognostic gene signature that effectively predicted recurrence-free survival in lung cancer in two validation cohorts. Resampling tests suggested that the prognostic power of the gene signature was not by chance, and multivariate analysis suggested that this gene signature was independent of the traditional clinical factors and enhanced the identification of lung cancer patients at greater risk for recurrence.

  4. Replicative Stress and the FHIT Gene: Roles in Tumor Suppression, Genome Stability and Prevention of Carcinogenesis

    Energy Technology Data Exchange (ETDEWEB)

    Karras, Jenna R.; Paisie, Carolyn A.; Huebner, Kay, E-mail: kay.huebner@osumc.edu [Department of Molecular Virology, Immunology and Medical Genetics, The Ohio State University Wexner Medical Center, Columbus, OH 43210 (United States)

    2014-06-04

    The fragile FHIT gene, encompassing the chromosomal fragile site FRA3B, is an early target of DNA damage in precancerous cells. While vulnerable to DNA damage itself, FHIT protein expression is essential to protect from DNA damage-induced cancer initiation and progression by modulating genome stability, oxidative stress and levels of accumulating DNA damage. Thus, FHIT, whose expression is lost or reduced in many human cancers, is a tumor suppressor and genome caretaker whose loss initiates genome instability in preneoplastic lesions. Ongoing studies are seeking more detailed understanding of the role of FHIT in the cellular response to oxidative damage. This review discusses the relationship between FHIT, reactive oxygen species production, and DNA damage in the context of cancer initiation and progression.

  5. Analysis of loss of heterozygosity of the tumor suppressor genes p53 and BRCA1 in ovarial carcinomas

    OpenAIRE

    Luković Ljiljana; Popović Branka; Atanacković Jasmina; Novaković Ivana; Perović Milica; Petrović Bojana; Petković Spasoje

    2006-01-01

    Background/aim: Among the genes involved in ovarian carcinogenesis, there has been increased interest in tumor-suppressor genes p53 and BRCA1. Both of the genes make control of cell cycle, DNA repair and apoptosis. The p53 is a "genome guardian" inactivated in more than 50% of human cancers, while BRCA1 mutations are found mostly in breast and ovarian cancer. The aim of this investigation was to establish the frequency of loss of heterozygosity (LOH) in the regions of the genes p53 and BRCA1 ...

  6. Dendrimer-Stabilized Gold Nanostars as a Multifunctional Theranostic Nanoplatform for CT Imaging, Photothermal Therapy, and Gene Silencing of Tumors.

    Science.gov (United States)

    Wei, Ping; Chen, Jingwen; Hu, Yong; Li, Xin; Wang, Han; Shen, Mingwu; Shi, Xiangyang

    2016-12-01

    Development of versatile nanomaterials combining diagnostic and therapeutic functionalities within one single nanoplatform is extremely important for tumor theranostics. In this work, the authors report the synthesis of a gold nanostar (Au NS)-based theranostic platform stabilized with cyclic arginine-glycine-aspartic (Arg-Gly-Asp, RGD) peptide-modified amine-terminated generation 3 poly(amidoamine) dendrimers. The formed RGD-modified dendrimer-stabilized Au NSs (RGD-Au DSNSs) are used as a gene delivery vector to complex small interfering RNA (siRNA) for computed tomography (CT) imaging, thermal imaging, photothermal therapy (PTT), and gene therapy of tumors. The results show that the RGD-Au DSNSs are able to compact vascular endothelial growth factor siRNA and specifically deliver siRNA to cancer cells overexpressing α v β 3 integrin. Under near-infrared laser irradiation, the viability of cancer cells is only 20.2% after incubation with the RGD-Au DSNS/siRNA polyplexes, which is much lower than that of cells after single PTT or gene therapy treatment. Furthermore, in vivo results show that the RGD-Au DSNS/siRNA polyplexes enable tumor CT imaging, thermal imaging, PTT, and gene therapy after intratumoral injection. These results indicate that the developed multifunctional nanoconstruct is a promising platform for tumor imaging and combinational PTT and gene therapy. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  7. Genome-wide DNA methylation analysis identifies MEGF10 as a novel epigenetically repressed candidate tumor suppressor gene in neuroblastoma.

    Science.gov (United States)

    Charlet, Jessica; Tomari, Ayumi; Dallosso, Anthony R; Szemes, Marianna; Kaselova, Martina; Curry, Thomas J; Almutairi, Bader; Etchevers, Heather C; McConville, Carmel; Malik, Karim T A; Brown, Keith W

    2017-04-01

    Neuroblastoma is a childhood cancer in which many children still have poor outcomes, emphasising the need to better understand its pathogenesis. Despite recent genome-wide mutation analyses, many primary neuroblastomas do not contain recognizable driver mutations, implicating alternate molecular pathologies such as epigenetic alterations. To discover genes that become epigenetically deregulated during neuroblastoma tumorigenesis, we took the novel approach of comparing neuroblastomas to neural crest precursor cells, using genome-wide DNA methylation analysis. We identified 93 genes that were significantly differentially methylated of which 26 (28%) were hypermethylated and 67 (72%) were hypomethylated. Concentrating on hypermethylated genes to identify candidate tumor suppressor loci, we found the cell engulfment and adhesion factor gene MEGF10 to be epigenetically repressed by DNA hypermethylation or by H3K27/K9 methylation in neuroblastoma cell lines. MEGF10 showed significantly down-regulated expression in neuroblastoma tumor samples; furthermore patients with the lowest-expressing tumors had reduced relapse-free survival. Our functional studies showed that knock-down of MEGF10 expression in neuroblastoma cell lines promoted cell growth, consistent with MEGF10 acting as a clinically relevant, epigenetically deregulated neuroblastoma tumor suppressor gene. © 2016 The Authors. Molecular Carcinogenesis Published by Wiley Periodicals, Inc. © 2016 The Authors. Molecular Carcinogenesis Published by Wiley Periodicals, Inc.

  8. Genome‐wide DNA methylation analysis identifies MEGF10 as a novel epigenetically repressed candidate tumor suppressor gene in neuroblastoma

    Science.gov (United States)

    Charlet, Jessica; Tomari, Ayumi; Dallosso, Anthony R.; Szemes, Marianna; Kaselova, Martina; Curry, Thomas J.; Almutairi, Bader; Etchevers, Heather C.; McConville, Carmel; Malik, Karim T. A.

    2016-01-01

    Neuroblastoma is a childhood cancer in which many children still have poor outcomes, emphasising the need to better understand its pathogenesis. Despite recent genome‐wide mutation analyses, many primary neuroblastomas do not contain recognizable driver mutations, implicating alternate molecular pathologies such as epigenetic alterations. To discover genes that become epigenetically deregulated during neuroblastoma tumorigenesis, we took the novel approach of comparing neuroblastomas to neural crest precursor cells, using genome‐wide DNA methylation analysis. We identified 93 genes that were significantly differentially methylated of which 26 (28%) were hypermethylated and 67 (72%) were hypomethylated. Concentrating on hypermethylated genes to identify candidate tumor suppressor loci, we found the cell engulfment and adhesion factor gene MEGF10 to be epigenetically repressed by DNA hypermethylation or by H3K27/K9 methylation in neuroblastoma cell lines. MEGF10 showed significantly down‐regulated expression in neuroblastoma tumor samples; furthermore patients with the lowest‐expressing tumors had reduced relapse‐free survival. Our functional studies showed that knock‐down of MEGF10 expression in neuroblastoma cell lines promoted cell growth, consistent with MEGF10 acting as a clinically relevant, epigenetically deregulated neuroblastoma tumor suppressor gene. © 2016 The Authors. Molecular Carcinogenesis Published by Wiley Periodicals, Inc. PMID:27862318

  9. Glycolysis-related gene induction and ATP reduction during fractionated irradiation. Markers for radiation responsiveness of human tumor xenografts

    Energy Technology Data Exchange (ETDEWEB)

    Goetze, K.; Meyer, S.S.; Mueller-Klieser, W. [University Medical Center Mainz Univ. (Germany). Inst. of Physiology and Pathophysiology; Yaromina, A. [Technical Univ. Dresden (Germany). OncoRay - National Center for Radiation Research in Oncology; Zips, D. [University Hospital Tuebingen (Germany). Dept. of Radiation Oncology; Baumann, M. [Technical Univ. Dresden (Germany). OncoRay - National Center for Radiation Research in Oncology; University Hospital Dresden Technical Univ. Dresden (Germany). Dept. of Radiation Oncology

    2013-09-15

    Background and purpose: Lactate was previously shown to be a prognostic but not a predictive pre-therapeutic marker for radiation response of tumor xenografts. We hypothesize that metabolic changes during fractionated irradiation may restrict the predictiveness of lactate regarding tumor radiosensitivity. Materials and methods: Tumor xenografts were generated in nude mice by implanting 4 head and neck squamous cell carcinoma lines with different sensitivities to fractionated irradiation. Tumors were irradiated with up to 15 fractions of 2 Gy over a period of 3 weeks, and ATP and lactate levels were measured in vital tumor areas with induced metabolic bioluminescence imaging. Corresponding changes in mRNA expression of glycolysis-related genes were determined by quantitative RT-PCR. Results: Lactate content decreased significantly in 3 out of 4 cell lines in the course of irradiation showing no correlation with cell line-specific radiosensitivity. Radiation-induced changes in ATP levels and glycolysis-related mRNA expression, however, only occurred in radiosensitive or intermediately radioresistant xenografts, whereas these parameters remained unchanged in radioresistant tumors. Conclusion: Sensitivity-related differences in the transcriptional response of tumors to radiotherapy may be exploited in the clinic for better individualization of tumor treatment. (orig.)

  10. Tumor-targeted inhibition by a novel strategy - mimoretrovirus expressing siRNA targeting the Pokemon gene.

    Science.gov (United States)

    Tian, Zhiqiang; Wang, Huaizhi; Jia, Zhengcai; Shi, Jinglei; Tang, Jun; Mao, Liwei; Liu, Hongli; Deng, Yijing; He, Yangdong; Ruan, Zhihua; Li, Jintao; Wu, Yuzhang; Ni, Bing

    2010-12-01

    Pokemon gene has crucial but versatile functions in cell differentiation, proliferation and tumorigenesis. It is a master regulator of the ARF-HDM2-p53 and Rb-E2F pathways. The facts that the expression of Pokemon is essential for tumor formation and many kinds of tumors over-express the Pokemon gene make it an attractive target for therapeutic intervention for cancer treatment. In this study, we used an RNAi strategy to silence the Pokemon gene in a cervical cancer model. To address the issues involving tumor specific delivery and durable expression of siRNA, we applied the Arg-Gly-Asp (RGD) peptide ligand and polylysine (K(18)) fusion peptide to encapsulate a recombinant retrovirus plasmid expressing a siRNA targeting the Pokemon gene and produced the 'mimoretrovirus'. At charge ratio 2.0 of fusion peptide/plasmid, the mimoretrovirus formed stable and homogenous nanoparticles, and provided complete DNase I protection and complete gel retardation. This nanoparticle inhibited SiHa cell proliferation and invasion, while it promoted SiHa cell apoptosis. The binding of the nanoparticle to SiHa cells was mediated via the RGD-integrin α(v)β(3) interaction, as evidenced by the finding that unconjugated RGD peptide inhibited this binding significantly. This tumor-targeting mimoretrovirus exhibited excellent anti-tumor capacity in vivo in a nude mouse model. Moreover, the mimoretrovirus inhibited tumor growth with a much higher efficiency than recombinant retrovirus expressing siRNA or the K(18)/P4 nanoparticle lacking the RGD peptide. Results suggest that the RNAi/RGD-based mimoretrovirus developed in this study represents a novel anti-tumor strategy that may be applicable to most research involving cancer therapy and, thus, has promising potential as a cervical cancer treatment.

  11. Genome-wide gene copy number and expression analysis of primary gastric tumors and gastric cancer cell lines

    International Nuclear Information System (INIS)

    Junnila, Siina; Kokkola, Arto; Karjalainen-Lindsberg, Marja-Liisa; Puolakkainen, Pauli; Monni, Outi

    2010-01-01

    Gastric cancer is one of the most common malignancies worldwide and the second most common cause of cancer related death. Gene copy number alterations play an important role in the development of gastric cancer and a change in gene copy number is one of the main mechanisms for a cancer cell to control the expression of potential oncogenes and tumor suppressor genes. To highlight genes of potential biological and clinical relevance in gastric cancer, we carried out a systematic array-based survey of gene expression and copy number levels in primary gastric tumors and gastric cancer cell lines and validated the results using an affinity capture based transcript analysis (TRAC assay) and real-time qRT-PCR. Integrated microarray analysis revealed altogether 256 genes that were located in recurrent regions of gains or losses and had at least a 2-fold copy number- associated change in their gene expression. The expression levels of 13 of these genes, ALPK2, ASAP1, CEACAM5, CYP3A4, ENAH, ERBB2, HHIPL2, LTB4R, MMP9, PERLD1, PNMT, PTPRA, and OSMR, were validated in a total of 118 gastric samples using either the qRT-PCR or TRAC assay. All of these 13 genes were differentially expressed between cancerous samples and nonmalignant tissues (p < 0.05) and the association between copy number and gene expression changes was validated for nine (69.2%) of these genes (p < 0.05). In conclusion, integrated gene expression and copy number microarray analysis highlighted genes that may be critically important for gastric carcinogenesis. TRAC and qRT-PCR analyses validated the microarray results and therefore the role of these genes as potential biomarkers for gastric cancer

  12. Coamplification in tumors of KRAS2, type 2 inositol 1,4,5 triphosphate receptor gene, and a novel human gene, KRAG

    Energy Technology Data Exchange (ETDEWEB)

    Heighway, J.; Betticher, D.C.; Altermatt, H.J. [Univ. Hospital of Berne (Switzerland)] [and others

    1996-07-01

    Analysis of a region of DNA, coamplified in tumors with KRAS2, resulted in the identification of the human homologue of the mouse KRAG gene. The gene was widely expressed in range of cell lines, tumors, and normal tissue and demonstrated a high degree of alternate splicing. A human KRAG cDNA sequence, with a structure similar to that encoded by the amplified gene in mouse Y1 adrenal carcinoma cells, was isolated by RT-PCR. The predicted amino acid similarity between the two sequences was 91%, and hydrophobicity plots suggested a structure closely resembling that of transmembrane 4 superfamily members. Identification of a PCR-based restriction fragment length polymorphism allele-specific splicing differences in tumors. Northern analysis of mRNA derived from a range of tissues suggested high level expression in muscle and confirmed alternate splicing. To facilitate the analysis of exon junctions, a YAC clone encoding the genomic sequence was identified. This allowed the localization of KRAG to human chromosome 12p11.2. Isolation of one end of this nonchimeric clone demonstrated a perfect match with a 247-bp sequence within the 3{prime} untranslated region of the type 2 1,4,5-inositol triphosphate receptor gene. Multiplex PCR confirmed the inclusion of both genes. Multiplex PCR confirmed the inclusion of both genes in the KRAS2 amplicon in human malignancy, suggesting that either may contribute to the malignant phenotypes. 35 refs., 6 figs., 1 tab.

  13. Quantitative gene expression of somatostatin receptors and noradrenaline transporter underlying scintigraphic results in patients with neuroendocrine tumors

    DEFF Research Database (Denmark)

    Binderup, Tina; Knigge, Ulrich; Mellon Mogensen, Anne

    2008-01-01

    AIM: To measure, by a quantitative approach, the gene expression underlying the results of somatostatin receptor (sst) scintigraphy ((111)In-DTPA-octreotide) and noradrenaline transporter (NAT) scintigraphy ((123)I-MIBG) in patients with neuroendocrine (NE) tumors. METHODS: The gene expression of...... to achieve a better understanding of the link between them, which in turn could aid in planning and development of noninvasive molecular imaging of key molecular processes....

  14. [Construction of Escherichia coli-Bifidobacterium longum shuttle vector and expression of tumor suppressor gene PTEN in B. longum].

    Science.gov (United States)

    Hou, Xin; Liu, Jun-E

    2006-06-01

    It was reported that Bifidobacterium longum accumulated specifically in hypoxic solid tumors, therefore could be used as a delivery system for cancer-specific gene therapy. Furthermore, construction of E.coli-B. longum shuttle vectors was proved by other research to be an efficient way for stable gene expression in B. longum. To obtain a shuttle vector and analyze the inhibition on mice solid tumors by genetically engineered B. longum, 48 primers with mutual overlaps were designed, assisted by software package Oligo 6.0. By PCR with the above primers, a linear plasmid was synthesized, which consists of pMB1 and HU gene promoter, both from B. longum. pMB-HU was constructed by cloning the synthesized linear plasmid into E.coli vector pMD 18-T, and was proved to be stably replicated in both E.coli DH5alpha and B. longum L17. By inserting PTEN cDNA into pMB-HU, expression vector pMB-HU-PTEN was obtained, in which PTEN gene was reported as a major tumor suppressor gene encoding a dual-specificity phosphatase. pMB-HU-PTEN was then transferred into B. longum L17 by electroporation. After transformation, an effective expression of PTEN in B. longum L17 was confirmed by Western blot, and significant inhibition on growth of mice solid tumors was also observed with the above genetically engineered B. longum. Those obtained results have laid foundation for tumor-targeting gene therapy with B. longum.

  15. Gene expression analysis supports tumor threshold over 2.0 cm for T-category breast cancer.

    Science.gov (United States)

    Solvang, Hiroko K; Frigessi, Arnoldo; Kaveh, Fateme; Riis, Margit L H; Lüders, Torben; Bukholm, Ida R K; Kristensen, Vessela N; Andreassen, Bettina K

    2016-12-01

    Tumor size, as indicated by the T-category, is known as a strong prognostic indicator for breast cancer. It is common practice to distinguish the T1 and T2 groups at a tumor size of 2.0 cm. We investigated the 2.0-cm rule from a new point of view. Here, we try to find the optimal threshold based on the differences between the gene expression profiles of the T1 and T2 groups (as defined by the threshold). We developed a numerical algorithm to measure the overall differential gene expression between patients with smaller tumors and those with larger tumors among multiple expression datasets from different studies. We confirmed the performance of the proposed algorithm by a simulation study and then applied it to three different studies conducted at two Norwegian hospitals. We found that the maximum difference in gene expression is obtained at a threshold of 2.2-2.4 cm, and we confirmed that the optimum threshold was over 2.0 cm, as indicated by a validation study using five publicly available expression datasets. Furthermore, we observed a significant differentiation between the two threshold groups in terms of time to local recurrence for the Norwegian datasets. In addition, we performed an associated network and canonical pathway analyses for the genes differentially expressed between tumors below and above the given thresholds, 2.0 and 2.4 cm, using the Norwegian datasets. The associated network function illustrated a cellular assembly of the genes for the 2.0-cm threshold: an energy production for the 2.4-cm threshold and an enrichment in lipid metabolism based on the genes in the intersection for the 2.0- and 2.4-cm thresholds.

  16. Differentiation-inducing factor-1 suppresses gene expression of cyclin D1 in tumor cells

    International Nuclear Information System (INIS)

    Yasmin, Tania; Takahashi-Yanaga, Fumi; Mori, Jun; Miwa, Yoshikazu; Hirata, Masato; Watanabe, Yutaka; Morimoto, Sachio; Sasaguri, Toshiyuki

    2005-01-01

    To determine the mechanism by which differentiation-inducing factor-1 (DIF-1), a morphogen of Dictyostelium discoideum, inhibits tumor cell proliferation, we examined the effect of DIF-1 on the gene expression of cyclin D1. DIF-1 strongly reduced the expression of cyclin D1 mRNA and correspondingly decreased the amount of β-catenin in HeLa cells and squamous cell carcinoma cells. DIF-1 activated glycogen synthase kinase-3β (GSK-3β) and inhibition of GSK-3β attenuated the DIF-1-induced β-catenin degradation, indicating the involvement of GSK-3β in this effect. Moreover, DIF-1 reduced the activities of T-cell factor (TCF)/lymphoid enhancer factor (LEF) reporter plasmid and a reporter gene driven by the human cyclin D1 promoter. Eliminating the TCF/LEF consensus site from the cyclin D1 promoter diminished the effect of DIF-1. These results suggest that DIF-1 inhibits Wnt/β-catenin signaling, resulting in the suppression of cyclin D1 promoter activity

  17. Cancer cell specific cytotoxic gene expression mediated by ARF tumor suppressor promoter constructs

    Energy Technology Data Exchange (ETDEWEB)

    Kurayoshi, Kenta [Department of Bioscience, School of Science and Technology, Kwansei Gakuin University, 2-1 Gakuen, Sanda, Hyogo 669-1337 (Japan); Ozono, Eiko [Centre for Molecular Oncology, Barts Cancer Institute, Queen Mary, University of London, John Vane Science Centre, Charterhouse Square, London EC1M 6BQ (United Kingdom); Iwanaga, Ritsuko; Bradford, Andrew P. [Department of Obstetrics and Gynecology, University of Colorado School of Medicine, Anschutz Medical Campus, 12800 East 19th Avenue, Aurora, CO 80045 (United States); Komori, Hideyuki [Center for Stem Cell Biology, Life Sciences Institute, University of Michigan, Ann Arbor, MI 48109 (United States); Ohtani, Kiyoshi, E-mail: btm88939@kwansei.ac.jp [Department of Bioscience, School of Science and Technology, Kwansei Gakuin University, 2-1 Gakuen, Sanda, Hyogo 669-1337 (Japan)

    2014-07-18

    Highlights: • ARF promoter showed higher responsiveness to deregulated E2F activity than the E2F1 promoter. • ARF promoter showed higher cancer cell-specificity than E2F1 promoter to drive gene expression. • HSV-TK driven by ARF promoter showed higher cancer cell-specific cytotoxicity than that driven by E2F1 promoter. - Abstract: In current cancer treatment protocols, such as radiation and chemotherapy, side effects on normal cells are major obstacles to radical therapy. To avoid these side effects, a cancer cell-specific approach is needed. One way to specifically target cancer cells is to utilize a cancer specific promoter to express a cytotoxic gene (suicide gene therapy) or a viral gene required for viral replication (oncolytic virotherapy). For this purpose, the selected promoter should have minimal activity in normal cells to avoid side effects, and high activity in a wide variety of cancers to obtain optimal therapeutic efficacy. In contrast to the AFP, CEA and PSA promoters, which have high activity only in a limited spectrum of tumors, the E2F1 promoter exhibits high activity in wide variety of cancers. This is based on the mechanism of carcinogenesis. Defects in the RB pathway and activation of the transcription factor E2F, the main target of the RB pathway, are observed in almost all cancers. Consequently, the E2F1 promoter, which is mainly regulated by E2F, has high activity in wide variety of cancers. However, E2F is also activated by growth stimulation in normal growing cells, suggesting that the E2F1 promoter may also be highly active in normal growing cells. In contrast, we found that the tumor suppressor ARF promoter is activated by deregulated E2F activity, induced by forced inactivation of pRB, but does not respond to physiological E2F activity induced by growth stimulation. We also found that the deregulated E2F activity, which activates the ARF promoter, is detected only in cancer cell lines. These observations suggest that ARF promoter

  18. DLC1 tumor suppressor gene inhibits migration and invasion of multiple myeloma cells through RhoA GTPase pathway

    Czech Academy of Sciences Publication Activity Database

    Ullmannová-Benson, Veronika; Guan, M.; Zhou, X. G.; Tripathi, V.; Yang, V.; Zimonjic, D. B.; Popescu, C.

    2009-01-01

    Roč. 23, č. 2 (2009), s. 383-390 ISSN 0887-6924 Institutional research plan: CEZ:AV0Z50200510 Keywords : multiple myeloma * tumor suppressor gene * promoter methylation Subject RIV: EC - Immunology Impact factor: 8.296, year: 2009

  19. Chemotherapy modulates intestinal immune gene expression including surfactant Protein-D and deleted in malignant brain tumors 1 in piglets

    DEFF Research Database (Denmark)

    Rathe, Mathias; Thomassen, Mads; Shen, René L.

    2016-01-01

    the BUCY and DOX piglets. Selected genes of potential biological significance with a similar change in expression across the treatments were controlled by real-time polymerase chain reaction. Key innate defense molecules, including surfactant protein-D and deleted in malignant brain tumors 1, were among...

  20. Tumor classification and marker gene prediction by feature selection and fuzzy c-means clustering using microarray data

    Directory of Open Access Journals (Sweden)

    Jonassen Inge

    2003-12-01

    Full Text Available Abstract Background Using DNA microarrays, we have developed two novel models for tumor classification and target gene prediction. First, gene expression profiles are summarized by optimally selected Self-Organizing Maps (SOMs, followed by tumor sample classification by Fuzzy C-means clustering. Then, the prediction of marker genes is accomplished by either manual feature selection (visualizing the weighted/mean SOM component plane or automatic feature selection (by pair-wise Fisher's linear discriminant. Results The proposed models were tested on four published datasets: (1 Leukemia (2 Colon cancer (3 Brain tumors and (4 NCI cancer cell lines. The models gave class prediction with markedly reduced error rates compared to other class prediction approaches, and the importance of feature selection on microarray data analysis was also emphasized. Conclusions Our models identify marker genes with predictive potential, often better than other available methods in the literature. The models are potentially useful for medical diagnostics and may reveal some insights into cancer classification. Additionally, we illustrated two limitations in tumor classification from microarray data related to the biology underlying the data, in terms of (1 the class size of data, and (2 the internal structure of classes. These limitations are not specific for the classification models used.

  1. PCR-RFLP to Detect Codon 248 Mutation in Exon 7 of "p53" Tumor Suppressor Gene

    Science.gov (United States)

    Ouyang, Liming; Ge, Chongtao; Wu, Haizhen; Li, Suxia; Zhang, Huizhan

    2009-01-01

    Individual genome DNA was extracted fast from oral swab and followed up with PCR specific for codon 248 of "p53" tumor suppressor gene. "Msp"I restriction mapping showed the G-C mutation in codon 248, which closely relates to cancer susceptibility. Students learn the concepts, detection techniques, and research significance of point mutations or…

  2. Sepsis syndrome and death in trauma patients are associated with variation in the gene encoding tumor necrosis factor.

    NARCIS (Netherlands)

    Menges, T.; Konig, I.R.; Hossain, H.; Little, S.; Tchatalbachev, S.; Thierer, F.; Hackstein, H.; Franjkovic, I.; Colaris, T.; Martens, F.; Weismuller, K.; Langefeld, T.; Stricker, J.; Hempelmann, G.; Vos, P.E.; Ziegler, A.; Jacobs, B.; Chakraborty, T.; Bein, G.

    2008-01-01

    OBJECTIVE: Patients encountering severe trauma are at risk of developing sepsis syndrome and subsequent multiple organ failure. This is often associated with fatal outcome despite survival of the initial injury. We postulate that variation of the gene coding for tumor necrosis factor (TNF)-alpha is

  3. Selector genes display tumor cooperation and inhibition in Drosophila epithelium in a developmental context-dependent manner

    Directory of Open Access Journals (Sweden)

    Ram Prakash Gupta

    2017-11-01

    Full Text Available During animal development, selector genes determine identities of body segments and those of individual organs. Selector genes are also misexpressed in cancers, although their contributions to tumor progression per se remain poorly understood. Using a model of cooperative tumorigenesis, we show that gain of selector genes results in tumor cooperation, but in only select developmental domains of the wing, haltere and eye-antennal imaginal discs of Drosophila larva. Thus, the field selector, Eyeless (Ey, and the segment selector, Ultrabithorax (Ubx, readily cooperate to bring about neoplastic transformation of cells displaying somatic loss of the tumor suppressor, Lgl, but in only those developmental domains that express the homeo-box protein, Homothorax (Hth, and/or the Zinc-finger protein, Teashirt (Tsh. In non-Hth/Tsh-expressing domains of these imaginal discs, however, gain of Ey in lgl− somatic clones induces neoplastic transformation in the distal wing disc and haltere, but not in the eye imaginal disc. Likewise, gain of Ubx in lgl− somatic clones induces transformation in the eye imaginal disc but not in its endogenous domain, namely, the haltere imaginal disc. Our results reveal that selector genes could behave as tumor drivers or inhibitors depending on the tissue contexts of their gains.

  4. Mutational profile of KIT and PDGFRA genes in gastrointestinal stromal tumors in Peruvian samples

    Directory of Open Access Journals (Sweden)

    José Buleje

    2015-02-01

    Full Text Available Introduction: Gastrointestinal stromal tumors (GISTs are mesenchymal neoplasms usually caused by somatic mutations in the genes KIT (c-KIT or PDGFRA. Mutation characterization has become an important exam for GIST patients because it is useful in predicting the response to the inhibitors of receptor tyrosine kinase (RTK. Objectives: The aim of this study was to determine the frequency of KIT and PDGFRA mutations in 25 GIST samples collected over two years at two national reference hospitals in Peru. There were 21 samples collected from the Instituto Nacional de Enfermedades Neoplásicas (INEN, national cancer center and 4 samples collected from Hospital A. Loayza. Methods and materials: In this retrospective study, we performed polymerase chain reaction (PCR amplification and deoxyribonucleic acid (DNA sequencing of KIT (exons 9, 11, 13, and 17 and PDGFRA (exons 12 and 18 genes in 20 FFPE (formalin-fixed, paraffin-embedded and 5 frozen GIST samples. Results: We report 21 mutations, including deletions, duplications, and missense, no mutations in 2 samples, and 2 samples with no useful DNA for further analysis. Eighty-six percent of these mutations were located in exon 11 of KIT, and 14 % were located in exon 18 of PDGFRA. Conclusions: Our study identified mutations in 21 out of 25 GIST samples from 2 referential national hospitals in Peru, and the mutation proportion follows a global tendency observed from previous studies (i.e., the majority of samples presented KIT mutations followed by a minor percentage of PDGFRA mutations. This study presents the first mutation data of the KIT and PDGFRA genes from Peruvian individuals with GIST.

  5. Graphene Functionalized with Arginine Decreases the Development of Glioblastoma Multiforme Tumor in a Gene-Dependent Manner

    Directory of Open Access Journals (Sweden)

    Ewa Sawosz

    2015-10-01

    Full Text Available Our previous studies revealed that graphene had anticancer properties in experiments in vitro with glioblastoma multiforme (GBM cells and in tumors cultured in vivo. We hypothesized that the addition of arginine or proline to graphene solutions might counteract graphene agglomeration and increase the activity of graphene. Experiments were performed in vitro with GBM U87 cells and in vivo with GBM tumors cultured on chicken embryo chorioallantoic membranes. The measurements included cell morphology, mortality, viability, tumor morphology, histology, and gene expression. The cells and tumors were treated with reduced graphene oxide (rGO and rGO functionalized with arginine (rGO + Arg or proline (rGO + Pro. The results confirmed the anticancer effect of graphene on GBM cells and tumor tissue. After functionalization with amino acids, nanoparticles were distributed more specifically, and the flakes of graphene were less agglomerated. The molecule of rGO + Arg did not increase the expression of TP53 in comparison to rGO, but did not increase the expression of MDM2 or the MDM2/TP53 ratio in the tumor, suggesting that arginine may block MDM2 expression. The expression of NQO1, known to be a strong protector of p53 protein in tumor tissue, was greatly increased. The results indicate that the complex of rGO + Arg has potential in GBM therapy.

  6. Graphene Functionalized with Arginine Decreases the Development of Glioblastoma Multiforme Tumor in a Gene-Dependent Manner

    Science.gov (United States)

    Sawosz, Ewa; Jaworski, Sławomir; Kutwin, Marta; Vadalasetty, Krishna Prasad; Grodzik, Marta; Wierzbicki, Mateusz; Kurantowicz, Natalia; Strojny, Barbara; Hotowy, Anna; Lipińska, Ludwika; Jagiełło, Joanna; Chwalibog, André

    2015-01-01

    Our previous studies revealed that graphene had anticancer properties in experiments in vitro with glioblastoma multiforme (GBM) cells and in tumors cultured in vivo. We hypothesized that the addition of arginine or proline to graphene solutions might counteract graphene agglomeration and increase the activity of graphene. Experiments were performed in vitro with GBM U87 cells and in vivo with GBM tumors cultured on chicken embryo chorioallantoic membranes. The measurements included cell morphology, mortality, viability, tumor morphology, histology, and gene expression. The cells and tumors were treated with reduced graphene oxide (rGO) and rGO functionalized with arginine (rGO + Arg) or proline (rGO + Pro). The results confirmed the anticancer effect of graphene on GBM cells and tumor tissue. After functionalization with amino acids, nanoparticles were distributed more specifically, and the flakes of graphene were less agglomerated. The molecule of rGO + Arg did not increase the expression of TP53 in comparison to rGO, but did not increase the expression of MDM2 or the MDM2/TP53 ratio in the tumor, suggesting that arginine may block MDM2 expression. The expression of NQO1, known to be a strong protector of p53 protein in tumor tissue, was greatly increased. The results indicate that the complex of rGO + Arg has potential in GBM therapy. PMID:26512645

  7. A jackknife-like method for classification and uncertainty assessment of multi-category tumor samples using gene expression information

    Directory of Open Access Journals (Sweden)

    Bertrand Keith

    2010-04-01

    Full Text Available Abstract Background The use of gene expression profiling for the classification of human cancer tumors has been widely investigated. Previous studies were successful in distinguishing several tumor types in binary problems. As there are over a hundred types of cancers, and potentially even more subtypes, it is essential to develop multi-category methodologies for molecular classification for any meaningful practical application. Results A jackknife-based supervised learning method called paired-samples test algorithm (PST, coupled with a binary classification model based on linear regression, was proposed and applied to two well known and challenging datasets consisting of 14 (GCM dataset and 9 (NC160 dataset tumor types. The results showed that the proposed method improved the prediction accuracy of the test samples for the GCM dataset, especially when t-statistic was used in the primary feature selection. For the NCI60 dataset, the application of PST improved prediction accuracy when the numbers of used genes were relatively small (100 or 200. These improvements made the binary classification method more robust to the gene selection mechanism and the size of genes to be used. The overall prediction accuracies were competitive in comparison to the most accurate results obtained by several previous studies on the same datasets and with other methods. Furthermore, the relative confidence R(T provided a unique insight into the sources of the uncertainty shown in the statistical classification and the potential variants within the same tumor type. Conclusion We proposed a novel bagging method for the classification and uncertainty assessment of multi-category tumor samples using gene expression information. The strengths were demonstrated in the application to two bench datasets.

  8. Analysis of loss of heterozygosity of the tumor suppressor genes p53 and BRCA1 in ovarial carcinomas

    Directory of Open Access Journals (Sweden)

    Luković Ljiljana

    2006-01-01

    Full Text Available Background/aim: Among the genes involved in ovarian carcinogenesis, there has been increased interest in tumor-suppressor genes p53 and BRCA1. Both of the genes make control of cell cycle, DNA repair and apoptosis. The p53 is a "genome guardian" inactivated in more than 50% of human cancers, while BRCA1 mutations are found mostly in breast and ovarian cancer. The aim of this investigation was to establish the frequency of loss of heterozygosity (LOH in the regions of the genes p53 and BRCA1 in ovarian carcinomas, and to analyze the association of LOH with the disease stage and prognosis. Methods. We analyzed 20 patients with a confirmed diagnosis of epithelilal ovarian carcinoma. DNA for molecular-genetic analysis was extracted from the tumor tissue and blood as normal tissue of each person. Microsatellite markers of the regions of genes p53 and BRCA1 were amplified by PCR method. The determination of allelic status of microsatellites and detection of LOH was performed after PAA gel electroforesis. Results. Both of the analyzed microsatellite markers were informative in 13/20 (65% cases. In the region of gene p53, LOH was established in 4/13 (30.7% tumors. One of them had histological gradus G1, one had gradus G2, and two of them had gradus G3, while all were with the International Federation of Gynecology and Obstetrics (FIGO IIIc stage. In the region of gene BRCA1, LOH was detected in 5/13 (38.5% tumors. Four of them had histological gradus G2, and one had gradus G3, while by the (FIGO classification one was with stage Ib, one was with stage IIIb, while the three were with stage IIIc. LOH in both of the analyzed regions was detected in one tumor (7.7%, with histological gradus G3 and the FIGO IIIc stage. Conclusion. The frequency of LOH in epthelial ovarian carcinomas was 30.7% and 38.5% for p53 and BRCA1 gene regions, respectively. Most of tumors with LOH had histological gradus G2 or G3, and the clinical FIGO stage IIIc, suggesting the

  9. [Analysis of loss of heterozygosity of the tumor suppressor genes p53 and BRCA1 in ovarial carcinomas].

    Science.gov (United States)

    Petrović, Bojana; Perović, Milica; Novaković, Ivana; Atanacković, Jasmina; Popović, Branka; Luković, Ljiljana; Petković, Spasoje

    2006-09-01

    Among the genes involved in ovarian carcinogenesis, there has been increased interest in tumor-suppressor genes p53 and BRCA1. Both of the genes make control of cell cycle, DNA repair and apoptosis. The p53 is a "genome guardian" inactivated in more than 50% of human cancers, while BRCA1 mutations are found mostly in breast and ovarian cancer. The aim of this investigation was to establish the frequency of loss of heterozygosity (LOH) in the regions of the genes p53 and BRCA1 in ovarian carcinomas, and to analyze the association of LOH with the disease stage and prognosis. We analyzed 20 patients with a confirmed diagnosis of epithelilal ovarian carcinoma. DNA for molecular-genetic analysis was extracted from the tumor tissue and blood as normal tissue of each person. Microsatellite markers of the regions of genes p53 and BRCA1 were amplified by PCR method. The determination of allelic status of microsatellites and detection of LOH was performed after PAA gel electroforesis. Both of the analyzed microsatellite markers were informative in 13/20 (65%) cases. In the region of gene p53, LOH was established in 4/13 (30.7%) tumors. One of them had histological gradus G1, one had gradus G2, and two of them had gradus G3, while all were with the International Federation of Gynecology and Obstetrics (FIGO) IIIc stage. In the region of gene BRCA1, LOH was detected in 5/13 (38.5%) tumors. Four of them had histological gradus G2, and one had gradus G3, while by the (FIGO) classification one was with stage Ib, one was with stage IIIb, while the three were with stage IlIc. LOH in both of the analyzed regions was detected in one tumor (7.70), with histological gradus G3 and the FIGO IIIc stage. The frequency of LOH in epthelial ovarian carcinomas was 30.7% and 38.5% for p53 and BRCA1 gene regions, respectively. Most of tumors with LOH had histological gradus G2 or G3, and the clinical FIGO stage IIIc, suggesting the association of this occurrence with a later phase of the disease.

  10. AC133+ progenitor cells as gene delivery vehicle and cellular probe in subcutaneous tumor models: a preliminary study

    Directory of Open Access Journals (Sweden)

    Knight Robert A

    2009-03-01

    Full Text Available Abstract Background Despite enormous progress in gene therapy for breast cancer, an optimal systemic vehicle for delivering gene products to the target tissue is still lacking. The purpose of this study was to determine whether AC133+ progenitor cells (APC can be used as both gene delivery vehicles and cellular probes for magnetic resonance imaging (MRI. In this study, we used superparamagentic iron oxide (SPIO-labeled APCs to carry the human sodium iodide symporter (hNIS gene to the sites of implanted breast cancer in mouse model. In vivo real time tracking of these cells was performed by MRI and expression of hNIS was determined by Tc-99m pertechnetate (Tc-99m scan. Results Three million human breast cancer (MDA-MB-231 cells were subcutaneously implanted in the right flank of nude mice. APCs, isolated from fresh human cord blood, were genetically transformed to carry the hNIS gene using adenoviral vectors and magnetically labeled with ferumoxides-protamine sulfate (FePro complexes. Magnetically labeled genetically transformed cells were administered intravenously in tumor bearing mice when tumors reached 0.5 cm in the largest dimension. MRI and single photon emission computed tomography (SPECT images were acquired 3 and 7 days after cell injection, with a 7 Tesla animal MRI system and a custom built micro-SPECT using Tc-99m, respectively. Expression of hNIS in accumulated cells was determined by staining with anti-hNIS antibody. APCs were efficiently labeled with ferumoxide-protamine sulfate (FePro complexes and transduced with hNIS gene. Our study showed not only the accumulation of intravenously administered genetically transformed, magnetically labeled APCs in the implanted breast cancer, but also the expression of hNIS gene at the tumor site. Tc-99m activity ratio (tumor/non-tumor was significantly different between animals that received non-transduced and transduced cells (P Conclusion This study indicates that genetically transformed

  11. A simple protocol for preparation of a liposomal vesicle with encapsulated plasmid DNA that mediate high accumulation and reporter gene activity in tumor tissue

    DEFF Research Database (Denmark)

    Gjetting, Torben; Andresen, Thomas Lars; Christensen, Camilla Laulund

    2011-01-01

    a simple protocol for the research-scale preparation of SPLPs from commercially available reagents with high amounts of encapsulated plasmid DNA. The SPLPs show properties of promising accumulation in tumor tissue in comparison to other organs when intravenously injected into xenograft tumor-bearing nude...... mice. Although transcriptionally targeted suicide gene therapy was not achieved, the SPLPs were capable of mediating reporter gene transfection in subcutaneous flank tumors originating from human small cell lung cancer....

  12. A simple protocol for preparation of a liposomal vesicle with encapsulated plasmid DNA that mediate high accumulation and reporter gene activity in tumor tissue

    DEFF Research Database (Denmark)

    Gjetting, Torben; Andresen, Thomas Lars; Christensen, Camilla Laulund

    2011-01-01

    a simple protocol for the research-scale preparation of SPLPs from commercially available reagents with high amounts of encapsulated plasmid DNA. The SPLPs show properties of promising accumulation in tumor tissue in comparison to other organs when intravenously injected into xenograft tumor-bearing nude...... mice. Although transcriptionally targeted suicide gene therapy was not achieved, the SPLPs were capable of mediating reporter gene transfection in subcutaneous ¿ank tumors originating from human small cell lung cancer....

  13. Combined comparative genomic hybridization and transcriptomic analyses of ovarian granulosa cell tumors point to novel candidate driver genes.

    Science.gov (United States)

    Caburet, Sandrine; Anttonen, Mikko; Todeschini, Anne-Laure; Unkila-Kallio, Leila; Mestivier, Denis; Butzow, Ralf; Veitia, Reiner A

    2015-04-10

    Ovarian granulosa cell tumors (GCTs) are the most frequent sex cord-stromal tumors. Several studies have shown that a somatic mutation leading to a C134W substitution in the transcription factor FOXL2 appears in more than 95% of adult-type GCTs. Its pervasive presence suggests that FOXL2 is the main cancer driver gene. However, other mutations and genomic changes might also contribute to tumor formation and/or progression. We have performed a combined comparative genomic hybridization and transcriptomic analyses of 10 adult-type GCTs to obtain a picture of the genomic landscape of this cancer type and to identify new candidate co-driver genes. Our results, along with a review of previous molecular studies, show the existence of highly recurrent chromosomal imbalances (especially, trisomy 14 and monosomy 22) and preferential co-occurrences (i.e. trisomy 14/monosomy 22 and trisomy 7/monosomy 16q). In-depth analyses showed the presence of recurrently broken, amplified/duplicated or deleted genes. Many of these genes, such as AKT1, RUNX1 and LIMA1, are known to be involved in cancer and related processes. Further genomic explorations suggest that they are functionally related. Our combined analysis identifies potential candidate genes, whose alterations might contribute to adult-type GCT formation/progression together with the recurrent FOXL2 somatic mutation.

  14. Effects of 5-aza-2′deoxycytidine on RECK gene expression and tumor invasion in salivary adenoid cystic carcinoma

    Energy Technology Data Exchange (ETDEWEB)

    Zhou, X.Q. [Department of Oral and Maxillofacial Surgery, School of Stomatology, Shandong University, Jinan (China); Department of Oral and Maxillofacial Surgery, The First People' s Hospital of Jining, Shandong (China); Department of Oral and Maxillofacial Surgery, Shandong Provincial Hospital, Affiliated to Shandong University, Jinan (China); Huang, S.Y. [Department of Oral and Maxillofacial Surgery, Shandong Provincial Hospital, Affiliated to Shandong University, Jinan (China); Zhang, D.S. [Department of Oral and Maxillofacial Surgery, School of Stomatology, Shandong University, Jinan (China); Department of Oral and Maxillofacial Surgery, Shandong Provincial Hospital, Affiliated to Shandong University, Jinan (China); Zhang, S.Z.; Li, W.G.; Chen, Z.W.; Wu, H.W. [Department of Oral and Maxillofacial Surgery, Shandong Provincial Hospital, Affiliated to Shandong University, Jinan (China)

    2014-12-12

    Reversion-inducing cysteine-rich protein with kazal motifs (RECK), a novel tumor suppressor gene that negatively regulates matrix metalloproteinases (MMPs), is expressed in various normal human tissues but downregulated in several types of human tumors. The molecular mechanism for this downregulation and its biological significance in salivary adenoid cystic carcinoma (SACC) are unclear. In the present study, we investigated the effects of a DNA methyltransferase (DNMT) inhibitor, 5-aza-2′deoxycytidine (5-aza-dC), on the methylation status of the RECK gene and tumor invasion in SACC cell lines. Methylation-specific PCR (MSP), Western blot analysis, and quantitative real-time PCR were used to investigate the methylation status of the RECK gene and expression of RECK mRNA and protein in SACC cell lines. The invasive ability of SACC cells was examined by the Transwell migration assay. Promoter methylation was only found in the ACC-M cell line. Treatment of ACC-M cells with 5-aza-dC partially reversed the hypermethylation status of the RECK gene and significantly enhanced the expression of mRNA and protein, and 5-aza-dC significantly suppressed ACC-M cell invasive ability. Our findings showed that 5-aza-dC inhibited cancer cell invasion through the reversal of RECK gene hypermethylation, which might be a promising chemotherapy approach in SACC treatment.

  15. NAB2-STAT6 fusion gene analysis in two cases of meningeal solitary fibrous tumor/hemangiopericytoma with late distant metastases.

    Science.gov (United States)

    Nakada, Satoko; Minato, Hiroshi; Takegami, Tsutomu; Kurose, Nozomu; Ikeda, Hiroko; Kobayashi, Masako; Sasagawa, Yasuo; Akai, Takuya; Kato, Takashi; Yamamoto, Norio; Nojima, Takayuki

    2015-10-01

    We present two cases of meningeal solitary fibrous tumor (SFT)/hemangiopericytoma (HPC) with immunohistochemistry of STAT6 and analysis of NAB2-STAT6 fusion genes. Case 1 was a 37-year-old male with a left middle fossa tumor; case 2 was a 68-year-old female with a cerebellar tumor. They showed late metastasis to the lung or bone 8 or 13 years, respectively, after the first surgery. Histology of both primary and metastatic tumors showed a cellular hemangiopericytomatous pattern with nuclear atypia. The primary tumors showed nuclear staining of STAT6, but both metastatic tumors showed nuclear and cytoplasmic STAT6. DNA sequencing revealed two kinds of NAB2-STAT6 fusion genes. One consisted of exon 6 of NAB2, intron 6 of NAB2, and the middle of exon 17 of STAT6 (observed in the primary and metastatic tumors of case 1); the other consisted of exon 6 of NAB2 and the beginning of exon 17 of STAT6 (observed in the metastatic tumor of case 2). The primary tumor of case 2 had both fusion genes. To the best of our knowledge, we are the first to report NAB2-STAT6 fusion gene analysis in primary and metastatic meningeal SFT/HPCs and a case showed different fusion gene status in the metastatic tumor.

  16. Association between TP53 gene Arg72Pro polymorphism and Wilms’ tumor risk in a Chinese population

    Directory of Open Access Journals (Sweden)

    Fu W

    2017-02-01

    Full Text Available Wen Fu,1,2,* Zhen-Jian Zhuo,3,* Wei Jia,1,2 Jinhong Zhu,4 Shi-Bo Zhu,1,2 Ze-Feng Lin,1,2 Feng-Hua Wang,1,2 Huimin Xia,1,2 Jing He,1,2 Guo-Chang Liu1,2 1Department of Pediatric Urology, Guangzhou Women and Children’s Medical Center, Guangzhou Medical University, Guangzhou, Guangdong, 2Department of Pediatric Surgery, Guangzhou Institute of Pediatrics, Guangzhou Women and Children’s Medical Center, Guangzhou Medical University, Guangzhou, Guangdong, 3Faculty of Medicine, School of Chinese Medicine, The Chinese University of Hong Kong, Hong Kong, 4Molecular Epidemiology Laboratory, Department of Laboratory Medicine, Harbin Medical University Cancer Hospital, Harbin, Heilongjiang, People’s Republic of China *These authors contributed equally to this work Abstract: Wilms’ tumor is one of the most prevalent pediatric malignancies, ranking fourth in childhood cancer worldwide. TP53 is a critical tumor suppressor gene, which encodes a 53 kDa protein, p53. The p53 functions to protect against cancer by regulating cell cycle and apoptosis and maintaining DNA integrity. TP53 gene is highly polymorphic. Several TP53 gene polymorphisms have been considered to be associated with cancer risk. Of them, a nonsynonymous polymorphism, Arg72Pro (rs1042522 C>G, has been most extensively studied for the association with cancer risk; however, few studies have investigated its effect on Wilms’ tumor. Because of the central role of p53 in cell cycle control, the TP53 gene Arg72Pro polymorphism is also a good potential candidate predisposition locus for this pediatric cancer. We genotyped this polymorphism in 145 patients and 531 cancer-free controls recruited from Chinese children by Taqman methodology. Overall, our result suggested a lack of association between the TP53 gene Arg72Pro polymorphism and Wilms’ tumor. In the stratified analysis, we found that carriers of CG/GG genotypes had a significantly increased Wilms’ tumor risk in children not older

  17. MTHFR variants reduce the risk of G:C->A:T transition mutations within the p53 tumor suppressor gene in colon tumors.

    Science.gov (United States)

    Ulrich, C M; Curtin, K; Samowitz, W; Bigler, J; Potter, J D; Caan, B; Slattery, M L

    2005-10-01

    5,10-Methylene-tetrahydrofolate reductase (MTHFR) is a key enzyme in folate-mediated 1-carbon metabolism. Reduced MTHFR activity has been associated with genomic DNA hypomethylation. Methylated cytosines at CpG sites are easily mutated and have been implicated in G:C-->A:T transitions in the p53 tumor suppressor gene. We investigated 2 polymorphisms in the MTHFR gene (C677T and A1298C) and their associations with colon tumor characteristics, including acquired mutations in Ki-ras and p53 genes and microsatellite instability (MSI). The study population comprised 1248 colon cancer cases and 1972 controls, who participated in a population-based case-control study and had been analyzed previously for MSI, acquired mutations in Ki-ras, p53, and germline MTHFR polymorphisms. Multivariable-adjusted odds ratios are presented. Overall, MTHFR genotypes were not associated with MSI status or the presence of any p53 or Ki-ras mutation. Individuals with homozygous variant MTHFR genotypes had a significantly reduced risk of G:C-->A:T transition mutations within the p53 gene, yet, as hypothesized, only at CpG-associated sites [677TT vs. 677CC (referent group) OR = 0.4 (95% CI: 0.1-0.8) for CpG-associated sites; OR = 1.5 (0.7-3.6) for non-CpG associated sites]. Genotypes conferring reduced MTHFR activity were associated with a decreased risk of acquired G:C-->A:T mutations within the p53 gene occurring at CpG sites. Consistent with evidence on the phenotypic effect of the MTHFR C677T variant, we hypothesize that this relation may be explained by modestly reduced genomic DNA methylation, resulting in a lower probability of spontaneous deamination of methylated cytosine to thymidine. These results suggest a novel mechanism by which MTHFR polymorphisms can affect the risk of colon cancer.

  18. Assessing tumor progression factors by somatic gene transfer into a mouse model: Bcl-xL promotes islet tumor cell invasion.

    Directory of Open Access Journals (Sweden)

    Yi-Chieh Nancy Du

    2007-10-01

    Full Text Available Tumors develop through multiple stages, implicating multiple effectors, but the tools to assess how candidate genes contribute to stepwise tumor progression have been limited. We have developed a novel system in which progression of phenotypes in a mouse model of pancreatic islet cell tumorigenesis can be used to measure the effects of genes introduced by cell-type-specific infection with retroviral vectors. In this system, bitransgenic mice, in which the rat insulin promoter (RIP drives expression of both the SV40 T antigen (RIP-Tag and the receptor for subgroup A avian leukosis virus (RIP-tva, are infected with avian viral vectors carrying cDNAs encoding candidate progression factors. Like RIP-Tag mice, RIP-Tag; RIP-tva bitransgenic mice develop isolated carcinomas by approximately 14 wk of age, after progression through well-defined stages that are similar to aspects of human tumor progression, including hyperplasia, angiogenesis, adenoma, and invasive carcinoma. When avian retroviral vectors carrying a green fluorescent protein marker were introduced into RIP-Tag; RIP-tva mice by intra-cardiac injection at the hyperplastic or early dysplastic stage of tumorigenesis, approximately 20% of the TVA-positive cells were infected and expressed green fluorescent proteins as measured by flow cytometry. Similar infection with vectors carrying cDNA encoding either of two progression factors, a dominant-negative version of cadherin 1 (dnE-cad or Bcl-xL, accelerated the formation of islet tumors with invasive properties and pancreatic lymph node metastasis. To begin studying the mechanism by which Bcl-xL, an anti-apoptotic protein, promotes invasion and metastasis, RIP-Tag; RIP-tva pancreatic islet tumor cells were infected in vitro with RCASBP-Bcl-xL. Although no changes were observed in rates of proliferation or apoptosis, Bcl-xL altered cell morphology, remodeled the actin cytoskeleton, and down-regulated cadherin 1; it also induced cell migration and

  19. Activating mutations in c-KIT and PDGFRalpha are exclusively found in gastrointestinal stromal tumors and not in other tumors overexpressing these imatinib mesylate target genes.

    Science.gov (United States)

    Burger, Herman; den Bakker, Michael A; Kros, Johan M; van Tol, Hans; de Bruin, Alex M; Oosterhuis, Wolter; van den Ingh, Harry F G M; van der Harst, Erwin; de Schipper, Hans P; Wiemer, Erik A C; Nooter, Kees

    2005-11-01

    Previous studies have shown that Imatinib mesylate (Gleevec), a selective tyrosine kinase inhibitor of c-KIT and platelet-derived growth factor receptors (PDGFR), is highly effective in c-KIT/CD117-positive gastrointestinal stromal tumors (GIST), especially in those having activating mutations in c-kit exon 11. In addition, gain-of-function mutations in the juxtamembrane domain (exon 12) and the kinase activation loop (exon 18) of PDGFRalpha were found in GISTs. Importantly, the presence and type of these mutually exclusive c-KIT or PDGFRalpha mutations were found to be associated with the response to imatinib. Here, we examined the prevalence of c-kit exon 11 and PDGFRalpha exons 12 and 18 mutations in other tumor types known to express these tyrosine kinase receptors in order to explore which other cancer types may potentially benefit from imatinib treatment. We determined the mutational status of these commonly mutated exons by direct sequencing in 11 different tumor types (in total: 215 unrelated cases), including GIST, chordoma, and various distinct tumors of lung, brain and its coverings, and skin cancer. Of the 579 exons examined (211 c-kit exon 11, 192 PDGFRalpha exon 12, 142 PDGFRalpha exon18, 17 PDGFRbeta exon 12 and 17 PDGFRbeta exon 18), only 12 (all GIST) harbored mutations (10 c-kit exon 11 and 2 PDGFRalpha exon18). From these data we conclude that activating c-KIT and PDGFR mutations are sporadic in human cancers known to overexpress these tyrosine kinase receptor genes and suggest that, except in GIST, this overexpression is not correlated with activating mutations. The latter may imply that these wild-type c-KIT and PDGFR tumor types will probably not benefit from imatinib treatment.

  20. Role of tumor suppressor genes in the cancer-associated reprogramming of human induced pluripotent stem cells.

    Science.gov (United States)

    Lin, Ying-Chu; Murayama, Yoshinobu; Hashimoto, Koichiro; Nakamura, Yukio; Lin, Chang-Shin; Yokoyama, Kazunari K; Saito, Shigeo

    2014-01-01

    Because of their pluripotent characteristics, human induced pluripotent stem cells (iPSCs) possess great potential for therapeutic application and for the study of degenerative disorders. These cells are generated from normal somatic cells, multipotent stem cells, or cancer cells. They express embryonic stem cell markers, such as OCT4, SOX2, NANOG, SSEA-3, SSEA-4, and REX1, and can differentiate into all adult tissue types, both in vitro and in vivo. However, some of the pluripotency-promoting factors have been implicated in tumorigenesis. Here, we describe the merits of tumor suppresser genes as reprogramming factors for the generation of iPSCs without tumorigenic activity. The initial step of reprogramming is induction of the exogenous pluripotent factors to generate the oxidative stress that leads to senescence by DNA damage and metabolic stresses, thus inducing the expression of tumor suppressor genes such as p21CIP1 and p16INK4a through the activation of p53 to be the pre-induced pluripotent stem cells (pre-iPSCs). The later stage includes overcoming the barrier of reprogramming-induced senescence or cell-cycle arrest by shutting off the function of these tumor suppressor genes, followed by the induction of endogenous stemness genes for the full commitment of iPSCs (full-iPSCs). Thus, the reactive oxygen species (ROS) produced by oxidative stress might be critical for the induction of endogenous reprogramming-factor genes via epigenetic changes or antioxidant reactions. We also discuss the critical role of tumor suppressor genes in the evaluation of the tumorigenicity of human cancer cell-derived pluripotent stem cells, and describe how to overcome their tumorigenic properties for application in stem cell therapy in the field of regenerative medicine.

  1. Physical mapping of a commonly deleted region, the site of a candidate tumor suppressor gene, at 12q22 in human male germ cell tumors

    Energy Technology Data Exchange (ETDEWEB)

    Murty, V.V.V.S.; Bosl, G.J.; Chaganti, R.S.K. [Memorial Sloan-Kettering Cancer Center, New York, NY (United States)] [and others

    1996-08-01

    A candidate tumor suppressor gene (TSG) site at 12q22 characterized by a high frequency of loss of heterozygosity (LOH) and a homozygous deletion has previously (LOH) and a homozygous deletion has previously been reported in human male germ cell tumors (GCTs). In a detailed deletion mapping analysis of 67 normal-tumor DNAs utilizing 20 polymorphic markers mapped to 12q22-q24, we identified the limits of the minimal region of deletion at 12q22 between D12S377 (priximal) and D12S296 (distal). We have constructed a YAC contig map of a 3-cM region of this band between the proximal marker D12S101 and the distal marker D12S346, which contained the minimal region of deletion in GCTs. The map is composed of 53 overlapping YACs and 3 cosmids onto which 25 polymorphic and nonpolymorphic sequence-tagged sites (STSs) were placed in a unique order. The size of the minimal region of deletion was approximately 2 Mb from overlapping, nonchimeric YACs that spanned the region. We also developed a radiation hybrid (RH) map of the region between D12S101 and D12S346 containing 17 loci. The consensus order developed by RH mapping is in good agreement with the YAC STS-content map order. The RH map estimated the distance between D12S101 and D12S346 to be 246 cR{sub 8000} and the minimal region of deletion to be 141 cR{sub 8000}. In addition, four genes that were previously mapped to 12q22 have been excluded as candidate genes. The leads gained from the deletion mapping and physical maps should expedite the isolation and characterization of the TSG at 12q22. 35 refs., 4 figs., 2 tabs.

  2. Multi-gene epigenetic silencing of tumor suppressor genes in T-cell lymphoma cells; delayed expression of the p16 protein upon reversal of the silencing

    DEFF Research Database (Denmark)

    Nagasawa, T; Zhang, Q; Raghunath, P N

    2006-01-01

    )-expressing T-cell lymphomas. p16 gene was epigenetically silenced in all but one of the 10 malignant T-cell lines examined, p15 gene silenced in roughly half of the lines, and p14 was the least frequently affected. Extensive methylation of the p16 promoter was seen in six out of 10 cutaneous T-cell lymphoma...... promoter demethylation and required up to 3 weeks to occur, seemingly reflecting late activation of the p16 gene. These findings indicate that epigenetic silencing affects in T-cell malignancies, often simultaneously, several tumor suppressor genes that impact on key cell functions. The observed...... differential silencing of p16 and p14, and to a lesser degree p15 gene, indicates that the silencing is governed by precise, promoter region-specific mechanisms. The study provides also further rationale for treatment of at least some types of T-cell lymphomas with DNA methyltransferase inhibitors to target...

  3. Hypermethylation of the 16q23.1 Tumor Suppressor Gene ADAMTS18 in Clear Cell Renal Cell Carcinoma

    Directory of Open Access Journals (Sweden)

    Ben Xu

    2015-01-01

    Full Text Available To identify tumor suppressor genes (TSGs silenced by hypermethylation and discover new epigenetic biomarkers for early cancer detection. ADAMTS18, located at 16q23.1, has been reported to be a critical TSG in multiple primary tumors; however, this has not yet been verified in clear cell renal cell carcinoma (ccRCC. We explored epigenetic alterations in this gene in ccRCC and analyzed possible clinicopathological associations. We examined ADAMTS18 gene expression and methylation by semi-quantitative reverse transcription PCR (RT-PCR and methylation-specific polymerase chain reaction (MSP in 5 ccRCC-derived cell lines before and after treatment with 5-aza-2'-deoxycytidine (5-AzaC. MSP was further performed for 101 ccRCC primary tumors and 20 adjacent normal tissues. Some cell lines and specimens were examined by subsequent bisulfite genomic sequencing (BGS and real-time PCR. Further, we analyzed the relationship between the ADAMTS18 gene methylation and clinicopathological features, including short-term disease-free survival (DFS, in patients with ccRCC. ADAMTS18 down-regulation and hypermethylation were detected in the ccRCC-derived cell lines using RT-PCR and MSP. Treatment with 5-AzaC reversed the hypermethylation of the ADAMTS18 gene and restored its expression. Hypermethylation was further detected in 44 of 101 (43.6% primary tumors and 3 of 20 (15.0% adjacent normal tissues. However, a significant difference between both groups was observed (p = 0.02. BGS analysis and real-time PCR were subsequently performed to confirm the results of RT-PCR and MSP. Furthermore, the methylation status of ADAMTS18 was not significantly associated with gender, age, location, tumor diameter, pathological stage, nuclear grade or short-term DFS in patients with ccRCC (p > 0.05. The ADAMTS18 gene is often down-regulated by hypermethylation in ccRCC-derived cell lines and primary tumors, indicating its critical role as a TSG in ccRCC. We conclude that ADAMTS18

  4. Analysis of Class I Major Histocompatibility Complex Gene Transcription in Human Tumors Caused by Human Papillomavirus Infection.

    Science.gov (United States)

    Gameiro, Steven F; Zhang, Ali; Ghasemi, Farhad; Barrett, John W; Nichols, Anthony C; Mymryk, Joe S

    2017-09-10

    Oncoproteins from high-risk human papillomaviruses (HPV) downregulate the transcription of the class I major histocompatibility complex (MHC-I) antigen presentation apparatus in tissue culture model systems. This could allow infected or transformed cells to evade the adaptive immune response. Using data from over 800 human cervical and head & neck tumors from The Cancer Genome Atlas (TCGA), we determined the impact of HPV status on the mRNA expression of all six MHC-I heavy chain genes, and the β2 microglobulin light chain. Unexpectedly, these genes were all expressed at high levels in HPV positive (HPV+) cancers compared with normal control tissues. Indeed, many of these genes were expressed at significantly enhanced levels in HPV+ tumors. Similarly, the transcript levels of several other components of the MHC-I peptide-loading complex were also high in HPV+ cancers. The coordinated expression of high mRNA levels of the MHC-I antigen presentation apparatus could be a consequence of the higher intratumoral levels of interferon γ in HPV+ carcinomas, which correlate with signatures of increased infiltration by T- and NK-cells. These data, which were obtained from both cervical and oral tumors in large human cohorts, indicates that HPV oncoproteins do not efficiently suppress the transcription of the antigen presentation apparatus in human tumors.

  5. Normalization of gene expression measurement of tissue samples obtained by transurethral resection of bladder tumors

    Directory of Open Access Journals (Sweden)

    Pop LA

    2016-06-01

    Full Text Available Laura A Pop,1,* Valentina Pileczki,1,2,* Roxana M Cojocneanu-Petric,1 Bogdan Petrut,3,4 Cornelia Braicu,1 Ancuta M Jurj,1 Rares Buiga,5 Patriciu Achimas-Cadariu,6,7 Ioana Berindan-Neagoe1,8 1The Research Center for Functional Genomics, Biomedicine and Translational Medicine, Iuliu Haţieganu University of Medicine and Pharmacy, Cluj-Napoca, Cluj, Romania; 2Department of Analytical Chemistry, Iuliu Haţieganu University of Medicine and Pharmacy, Cluj-Napoca, Cluj, Romania; 3Department of Surgery II – Urology, The Oncology Institute “Prof Dr Ion Chiricuţă”, Cluj-Napoca, Cluj, Romania; 4Department of Urology, Iuliu Haţieganu University of Medicine and Pharmacy, Cluj-Napoca, Cluj, Romania; 5Department of Pathology, The Oncology Institute “Prof. Dr Ion Chiricuţă”, Cluj-Napoca, Cluj, Romania; 6Department of Surgery, The Oncology Institute “Prof Dr Ion Chiricuţă”, Cluj-Napoca, Cluj, Romania; 7Department of Surgical Oncology and Gynecological Oncology, Iuliu Haţieganu University of Medicine and Pharmacy, 8Department of Functional Genomics and Experimental Pathology, The Oncology Institute “Prof Dr Ion Chiricuţă”, Cluj-Napoca, Cluj, Romania *These authors contributed equally to this work Background: Sample processing is a crucial step for all types of genomic studies. A major challenge for researchers is to understand and predict how RNA quality affects the identification of transcriptional differences (by introducing either false-positive or false-negative errors. Nanotechnologies help improve the quality and quantity control for gene expression studies. Patients and methods: The study was performed on 14 tumor and matched normal pairs of tissue from patients with bladder urothelial carcinomas. We assessed the RNA quantity by using the NanoDrop spectrophotometer and the quality by nano-microfluidic capillary electrophoresis technology provided by Agilent 2100 Bioanalyzer. We evaluated the amplification status of three

  6. A preclinical model for noninvasive imaging of hypoxia-induced gene expression; comparison with an exogenous marker of tumor hypoxia

    International Nuclear Information System (INIS)

    Wen Bixiu; Burgman, Paul; Zanzonico, Pat; O'Donoghue, Joseph; Li, Gloria C.; Ling, C. Clifton; Cai Shangde; Finn, Ron; Serganova, Inna; Blasberg, Ronald; Gelovani, Juri

    2004-01-01

    Hypoxia is associated with tumor aggressiveness and is an important cause of resistance to radiation therapy and chemotherapy. Assays of tumor hypoxia could provide selection tools for hypoxia-modifying treatments. The purpose of this study was to develop and characterize a rodent tumor model with a reporter gene construct that would be transactivated by the hypoxia-inducible molecular switch, i.e., the upregulation of HIF-1. The reporter gene construct is the herpes simplex virus 1-thymidine kinase (HSV1-tk) fused with the enhanced green fluorescent protein (eGFP) under the regulation of an artificial hypoxia-responsive enhancer/promoter. In this model, tumor hypoxia would up-regulate HIF-1, and through the hypoxia-responsive promoter transactivate the HSV1-tkeGFPfusion gene. The expression of this reporter gene can be assessed with the 124 I-labeled reporter substrate 2'-fluoro-2'-deoxy-1-β-d-arabinofuranosyl-5-iodouracil ( 124 I-FIAU), which is phosphorylated by the HSV1-tk enzyme and trapped in the hypoxic cells. Animal positron emission tomography (microPET) and phosphor plate imaging (PPI) were used in this study to visualize the trapped 124 I-FIAU, providing a distribution of the hypoxia-induced molecular events. The distribution of 124 I-FIAU was also compared with that of an exogenous hypoxic cell marker, 18 F-fluoromisonidazole (FMISO). Our results showed that 124 I-FIAU microPET imaging of the hypoxia-induced reporter gene expression is feasible, and that the intratumoral distributions of 124 I-FIAU and 18 F-FMISO are similar. In tumor sections, detailed radioactivity distributions were obtained with PPI which also showed similarity between 124 I-FIAU and 18 F-FMISO. This reporter system is sufficiently sensitive to detect hypoxia-induced transcriptional activation by noninvasive imaging and might provide a valuable tool in studying tumor hypoxia and in validating existing and future exogenous markers for tumor hypoxia. (orig.)

  7. Are there tumor suppressor genes on chromosome 4p in sporadic colorectal carcinoma?

    Science.gov (United States)

    Zheng, Hai-Tao; Jiang, Li-Xin; Lv, Zhong-Chuan; Li, Da-Peng; Zhou, Chong-Zhi; Gao, Jian-Jun; He, Lin; Peng, Zhi-Hai

    2008-01-07

    To study the candidate tumor suppressor genes (TSG) on chromosome 4p by detecting the high frequency of loss of heterozygosity (LOH) in sporadic colorectal carcinoma in Chinese patients. Seven fluorescent labeled polymorphic microsatellite markers were analyzed in 83 cases of colorectal carcinoma and matched normal tissue DNA by PCR. PCR products were electrophoresed on an ABI 377 DNA sequencer. Genescan 3.7 and Genotype 3.7 software were used for LOH scanning and analysis. The same procedure was performed by the other six microsatellite markers spanning D4S3013 locus to make further detailed deletion mapping. Comparison between LOH frequency and clinicopathological factors was performed by c2 test. Data were collected from all informative loci. The average LOH frequency on 4p was 24.25%, and 42.3% and 35.62% on D4S405 and D4S3013 locus, respectively. Adjacent markers of D4S3013 displayed a low LOH frequency (4p15.2) and D4S405 (4p14) locus are detected. Candidate TSG, which is involved in carcinogenesis and progression of sporadic colorectal carcinoma on chromosome 4p, may be located between D4S3017 and D4S2933 (about 1.7 cm).

  8. Inactivation of tumor suppressor genes and cancer therapy: An evolutionary game theory approach.

    Science.gov (United States)

    Khadem, Heydar; Kebriaei, Hamed; Veisi, Zahra

    2017-06-01

    Inactivation of alleles in tumor suppressor genes (TSG) is one of the important issues resulting in evolution of cancerous cells. In this paper, the evolution of healthy, one and two missed allele cells is modeled using the concept of evolutionary game theory and replicator dynamics. The proposed model also takes into account the interaction rates of the cells as designing parameters of the system. Different combinations of the equilibrium points of the parameterized nonlinear system is studied and categorized into some cases. In each case, the interaction rates' values are suggested in a way that the equilibrium points of the replicator dynamics are located on an appropriate region of the state space. Based on the suggested interaction rates, it is proved that the system doesn't have any undesirable interior equilibrium point as well. Therefore, the system will converge to the desirable region, where there is a scanty level of cancerous cells. In addition, the proposed conditions for interaction rates guarantee that, when a trajectory of the system reaches the boundaries, then it will stay there forever which is a desirable property since the equilibrium points have been already located on the boundaries, appropriately. The simulation results show the effectiveness of the suggestions in the elimination of the cancerous cells in different scenarios. Copyright © 2017 Elsevier Inc. All rights reserved.

  9. Expression of angiogenesis-related genes in canine cortisol-secreting adrenocortical tumors.

    Science.gov (United States)

    Kool, M M J; Galac, S; Kooistra, H S; Mol, J A

    2014-04-01

    The aim of this study was to evaluate the expression of angiogenesis-related genes in canine cortisol-secreting adrenocortical tumors (ATs). Quantitative RT-PCR analysis revealed mRNA encoding for vascular endothelial growth factor, vascular endothelial growth factor receptors 1 and 2, angiopoietin 1 and 2 (ANGPT1 and ANGPT2), the splice variant ANGPT2443, the ANGPT-receptor Tie2, and basic fibroblast growth factor in 38 canine cortisol-secreting ATs (26 carcinomas and 12 adenomas) and 15 normal adrenals. The relative expression of both ANGPT2 and ANGPT2443 was higher in adenomas (P = 0.020 for ANGPT2 and P = 0.002 for ANGPT2443) and carcinomas (P = 0.003 for ANGPT2 and P cortisol-producing adrenocortical carcinoma cell line, we were able to demonstrate that the ANGPT2 expression was stimulated by cyclic adenosine monophosphate and progesterone but not by cortisol. In conclusion, canine cortisol-secreting ATs have enhanced ANGPT2 expression with a concomitant shift toward a proangiogenic state. On the basis of this information, treatment modalities may be developed that interfere with ANGPT2 expression, including inhibition of the cyclic adenosine monophosphate/protein kinase A pathway, or of the effect of ANGPT2, by using specific ANGPT2 inhibitors. Copyright © 2014 Elsevier Inc. All rights reserved.

  10. Structural Stability of the Coiled-Coil Domain of Tumor Susceptibility Gene (TSG)-101.

    Science.gov (United States)

    White, Jordan T; Toptygin, Dmitri; Cohen, Randy; Murphy, Natalie; Hilser, Vincent J

    2017-09-05

    The tumor susceptibility gene-101 coiled coil domain (TSG101cc) is an integral component of the endosomal maturation machinery and cytokinesis, and also interacts with several transcription factors. The TSG101cc has been crystallized as a homotetramer but is known to interact with two of its binding partners as a heterotrimer. To investigate this apparent discrepancy, we examined the solution thermodynamics of the TSG101cc. Here, we use circular dichroism, differential scanning calorimetry, analytical ultracentrifugation, fluorescence, and structural thermodynamic analysis to investigate the structural stability and the unfolding of the TSG101cc. We demonstrate that TSG101cc exists in solution primarily as a tetramer, which unfolds in a two-state manner. Surprisingly, no homodimeric or homotrimeric species were detected. Structural thermodynamic analysis of the homotetrameric structure and comparison with known oligomeric coiled-coils suggests that the TSG101cc homotetramer is comparatively unstable on a per residue basis. Furthermore, the homotrimeric coiled-coil is predicted to be much less stable than the functional heterotrimeric coiled-coil in the endosomal sorting complex required for transport 1 (ESCRT1). These results support a model whereby the tetramer-monomer equilibrium of TSG101 serves as the cellular reservoir of TSG101, which is effectively outcompeted when its binding partners are present and the heteroternary complex can form.

  11. Partial loss of heterozygosity events at the mutated gene in tumors from MLH1/MSH2 large genomic rearrangement carriers

    International Nuclear Information System (INIS)

    Zavodna, Katarina; Krivulcik, Tomas; Bujalkova, Maria Gerykova; Slamka, Tomas; Martinicky, David; Ilencikova, Denisa; Bartosova, Zdena

    2009-01-01

    Depending on the population studied, large genomic rearrangements (LGRs) of the mismatch repair (MMR) genes constitute various proportions of the germline mutations that predispose to hereditary non-polyposis colorectal cancer (HNPCC). It has been reported that loss of heterozygosity (LOH) at the LGR region occurs through a gene conversion mechanism in tumors from MLH1/MSH2 deletion carriers; however, the converted tracts were delineated only by extragenic microsatellite markers. We sought to determine the frequency of LGRs in Slovak HNPCC patients and to study LOH in tumors from LGR carriers at the LGR region, as well as at other heterozygous markers within the gene to more precisely define conversion tracts. The main MMR genes responsible for HNPCC, MLH1, MSH2, MSH6, and PMS2, were analyzed by MLPA (multiplex ligation-dependent probe amplification) in a total of 37 unrelated HNPCC-suspected patients whose MLH1/MSH2 genes gave negative results in previous sequencing experiments. An LOH study was performed on six tumors from LGR carriers by combining MLPA to assess LOH at LGR regions and sequencing to examine LOH at 28 SNP markers from the MLH1 and MSH2 genes. We found six rearrangements in the MSH2 gene (five deletions and dup5-6), and one aberration in the MLH1 gene (del5-6). The MSH2 deletions were of three types (del1, del1-3, del1-7). We detected LOH at the LGR region in the single MLH1 case, which was determined in a previous study to be LOH-negative in the intragenic D3S1611 marker. Three tumors displayed LOH of at least one SNP marker, including two cases that were LOH-negative at the LGR region. LGRs accounted for 25% of germline MMR mutations identified in 28 Slovakian HNPCC families. A high frequency of LGRs among the MSH2 mutations provides a rationale for a MLPA screening of the Slovakian HNPCC families prior scanning by DNA sequencing. LOH at part of the informative loci confined to the MLH1 or MSH2 gene (heterozygous LGR region, SNP, or

  12. Involvement of aberrant DNA methylation on reduced expression of lysophosphatidic acid receptor-1 gene in rat tumor cell lines

    International Nuclear Information System (INIS)

    Tsujiuchi, Toshifumi; Shimizu, Kyoko; Onishi, Mariko; Sugata, Eriko; Fujii, Hiromasa; Mori, Toshio; Honoki, Kanya; Fukushima, Nobuyuki

    2006-01-01

    Lysophosphatidic acid (LPA) is a bioactive phospholipid that stimulates cell proliferation, migration, and protects cells from apoptosis. It interacts with specific G protein-coupled transmembrane receptors. Recently, it has been reported that alterations of LPA receptor expression might be important in the malignant transformation of tumor cells. Therefore, to assess an involvement of DNA methylation in reduced expression of the LPA receptor-1 (lpa1) gene, we investigated the expression of the lpa1 gene and its DNA methylation patterns in rat tumor cell lines. Both rat brain-derived neuroblastoma B103 and liver-derived hepatoma RH7777 cells used in this study indicated no expression of lpa1. For the analysis of methylation status, bisulfite sequencing was performed with B103 and RH7777 cells, comparing with other lpa1 expressed cells and normal tissues of brain and liver. The lpa1 expressed cells and tissues were all unmethylated in this region of lpa1. In contrast, both B103 and RH7777 cells were highly methylated, correlating with reduced expression of the lpa1. Treatment with 5-aza 2'-deoxycytidine induced expression of lpa1 gene in B103 and RH7777 cells after 24 h. In RH7777 cells treated with 5-aza 2'-deoxycytidine, stress fiber formation was also observed in response to LPA in RH7777 cells, but not in untreated RH7777 cells. These results suggest that aberrant DNA methylation of the lpa1 gene may be involved in its reduced expression in rat tumor cells

  13. Imaging targeted at tumor with 188Re-labeled VEGF189 exon 6-encoded peptide and effects of the transfecting truncated KDR gene in tumor-bearing nude mice

    International Nuclear Information System (INIS)

    Qin Zhexue; Li Qianwei; Liu Guangyuan; Luo Chaoxue; Xie Ganfeng; Zheng Lei; Huang Dingde

    2009-01-01

    Introduction: Planar imaging of 188 Re-labeled vascular endothelial growth factor (VEGF) 189 exon 6-encoded peptide (QKRKRKKSRYKS) with single photon emission computed tomography (SPECT) in tumor-bearing nude mice and effects of the transfecting truncated KDR gene on its imaging were investigated, so as to provide a basis for further applying the peptide to tumor-targeted radionuclide treatment. Methods: QKRKRKKSRYKS, coupling with mercaptoacetyltriglycine (MAG 3 ) chelator was labeled with 188 Re; then in vivo distribution, planar imaging with SPECT and blocking experiment in tumor-bearing nude mice were analyzed. Recombinant adenovirus vectors carrying the truncated KDR gene were constructed to transfect tumor tissues to evaluate the effects of truncated KDR on the in vivo distribution and tumor planar imaging of 188 Re-MAG 3 -QKRKRKKSRYKS in tumor-bearing nude mice. Results: The labeled peptide exhibited a sound receptor binding activity. Planar imaging with SPECT demonstrated significant radioactivity accumulation in tumor 1 h after injection of the labeled peptide and disappearance of radioactivity 3 h later. Significant radioactivity accumulation was also observed in the liver, intestines and kidneys but was not obvious in other tissues. An hour after injection of the labeled peptide, the percentage of the injected radioactive dose per gram (%ID/g) of tumor and tumor/contralateral muscle tissues ratio were 1.98±0.38 and 2.53±0.33, respectively, and increased to 3.08±0.84 and 3.61±0.59 in the group transfected with the truncated KDR gene, respectively, and radioactivity accumulation in tumor with planar imaging also increased significantly in the transfection group. Conclusion: 188 Re-MAG 3 -QKRKRKKSRYKS can accumulate in tumor tissues, which could be increased by the transfection of truncated KDR gene. This study provides a basis for further applying the peptide to tumor targeted radionuclide imaging and treatment.

  14. CT perfusion as an imaging biomarker in monitoring response to neoadjuvant bevacizumab and radiation in soft-tissue sarcomas: comparison with tumor morphology, circulating and tumor biomarkers, and gene expression.

    Science.gov (United States)

    Kambadakone, Avinash; Yoon, Sam S; Kim, Tae-Min; Karl, Daniel L; Duda, Dan G; DeLaney, Thomas F; Sahani, Dushyant V

    2015-01-01

    The purpose of this study was to evaluate the role of CT perfusion in monitoring response to neoadjuvant antiangiogenic and radiation therapy in resectable soft-tissue sarcomas and correlate the findings with tumor size, circulating and tumor biomarkers, and gene expression. This phase II clinical trial included 20 patients (13 men and 7 women; mean age, 55 years) with soft-tissue sarcomas who were undergoing treatment with the antiangiogenic drug bevacizumab followed by bevacizumab, radiation, and surgical resection. The patients underwent CT perfusion and diagnostic contrast-enhanced CT at baseline, at 2 weeks after bevacizumab therapy, and after completion of bevacizumab and radiation therapy. Multiple CT perfusion parameters (blood flow, blood volume, mean transit time, and permeability) were correlated with tumor size, circulating and tumor biomarkers, and gene expression. Two weeks after bevacizumab therapy, there was substantial fall in blood volume (31.9% reduction, p = 0.01) with more pronounced reduction in blood flow, blood volume, and permeability after treatment completion (53-64% reduction in blood flow, blood volume, and permeability; p = 0.001), whereas tumor size showed no significant change (p = 0.34). Tumors with higher baseline blood volume and lower baseline tumor size showed superior response to bevacizumab and radiation (p = 0.05). There was also an increase in median plasma vascular endothelial growth factor and placental-derived growth factor concentration after bevacizumab therapy paralleled by a decrease in tumor perfusion depicted by CT perfusion, although this was not statistically significant (p = 0.4). The baseline tumor microvessel density (MVD) correlated with blood flow (p = 0.04). At least 20 different genes were differentially expressed in tumors with higher and lower baseline perfusion. CT perfusion is more sensitive than tumor size for monitoring early and late response to bevacizumab and radiation therapy. CT perfusion

  15. Effect of restoration of retinoblastoma gene function on the radiosensitivity of cells of human tumor cell lines

    International Nuclear Information System (INIS)

    Tsang, N.M.; Little, J.B.

    1994-01-01

    To assess the role of expression of the retinoblastoma (RB) gene on the sensitivity of cells to the cytotoxic effects of ionizing radiation, we transfected a normal RB gene into cells of RB + and RB - osteosarcoma cell lines and an RB - prostate carcinoma line and studied the radiosensitivity of the cells before and after transfection. Four transfected clones were isolated from the two RB - tumor cell lines that expressed the product of the transfected normal RB gene and contained no mutations in the pocket and C-terminal regions by sequencing. A small increase in radiosensitivity was observed in cell lines transfected with the pDOL plasmid vector alone, containing the neo gene and a long terminal repeat (LTR) promoter. However, no significant change in radiosensitivity occurred in transfected cells expressing the normal RB gene compared to controls transfected with an RB - plasmid. Based on this and other information, we conclude that RB gene function is not involved in the response of these human tumor cells to the cytotoxic effects of radiation. 38 refs., 5 figs., 4 tabs

  16. The Tumor Suppressor Gene, RASSF1A, Is Essential for Protection against Inflammation -Induced Injury

    Science.gov (United States)

    Fiteih, Yahya; Law, Jennifer; Volodko, Natalia; Mohamed, Anwar; El-Kadi, Ayman O. S.; Liu, Lei; Odenbach, Jeff; Thiesen, Aducio; Onyskiw, Christina; Ghazaleh, Haya Abu; Park, Jikyoung; Lee, Sean Bong; Yu, Victor C.; Fernandez-Patron, Carlos; Alexander, R. Todd; Wine, Eytan; Baksh, Shairaz

    2013-01-01

    Ras association domain family protein 1A (RASSF1A) is a tumor suppressor gene silenced in cancer. Here we report that RASSF1A is a novel regulator of intestinal inflammation as Rassf1a+/−, Rassf1a−/− and an intestinal epithelial cell specific knockout mouse (Rassf1a IEC-KO) rapidly became sick following dextran sulphate sodium (DSS) administration, a chemical inducer of colitis. Rassf1a knockout mice displayed clinical symptoms of inflammatory bowel disease including: increased intestinal permeability, enhanced cytokine/chemokine production, elevated nuclear factor of kappa light polypeptide gene enhancer in B-cells (NFκB) activity, elevated colonic cell death and epithelial cell injury. Furthermore, epithelial restitution/repair was inhibited in DSS-treated Rassf1a−/− mice with reduction of several makers of proliferation including Yes associated protein (YAP)-driven proliferation. Surprisingly, tyrosine phosphorylation of YAP was detected which coincided with increased nuclear p73 association, Bax-driven epithelial cell death and p53 accumulation resulting in enhanced apoptosis and poor survival of DSS-treated Rassf1a knockout mice. We can inhibit these events and promote the survival of DSS-treated Rassf1a knockout mice with intraperitoneal injection of the c-Abl and c-Abl related protein tyrosine kinase inhibitor, imatinib/gleevec. However, p53 accumulation was not inhibited by imatinib/gleevec in the Rassf1a−/− background which revealed the importance of p53-dependent cell death during intestinal inflammation. These observations suggest that tyrosine phosphorylation of YAP (to drive p73 association and up-regulation of pro-apoptotic genes such as Bax) and accumulation of p53 are consequences of inflammation-induced injury in DSS-treated Rassf1a−/− mice. Mechanistically, we can detect robust associations of RASSF1A with membrane proximal Toll-like receptor (TLR) components to suggest that RASSF1A may function to interfere and restrict TLR

  17. Identification of novel candidate target genes in amplicons of Glioblastoma multiforme tumors detected by expression and CGH microarray profiling

    Directory of Open Access Journals (Sweden)

    Hernández-Moneo Jose-Luis

    2006-09-01

    Full Text Available Abstract Background Conventional cytogenetic and comparative genomic hybridization (CGH studies in brain malignancies have shown that glioblastoma multiforme (GBM is characterized by complex structural and numerical alterations. However, the limited resolution of these techniques has precluded the precise identification of detailed specific gene copy number alterations. Results We performed a genome-wide survey of gene copy number changes in 20 primary GBMs by CGH on cDNA microarrays. A novel amplicon at 4p15, and previously uncharacterized amplicons at 13q32-34 and 1q32 were detected and are analyzed here. These amplicons contained amplified genes not previously reported. Other amplified regions containg well-known oncogenes in GBMs were also detected at 7p12 (EGFR, 7q21 (CDK6, 4q12 (PDGFRA, and 12q13-15 (MDM2 and CDK4. In order to identify the putative target genes of the amplifications, and to determine the changes in gene expression levels associated with copy number change events, we carried out parallel gene expression profiling analyses using the same cDNA microarrays. We detected overexpression of the novel amplified genes SLA/LP and STIM2 (4p15, and TNFSF13B and COL4A2 (13q32-34. Some of the candidate target genes of amplification (EGFR, CDK6, MDM2, CDK4, and TNFSF13B were tested in an independent set of 111 primary GBMs by using FISH and immunohistological assays. The novel candidate 13q-amplification target TNFSF13B was amplified in 8% of the tumors, and showed protein expression in 20% of the GBMs. Conclusion This high-resolution analysis allowed us to propose novel candidate target genes such as STIM2 at 4p15, and TNFSF13B or COL4A2 at 13q32-34 that could potentially contribute to the pathogenesis of these tumors and which would require futher investigations. We showed that overexpression of the amplified genes could be attributable to gene dosage and speculate that deregulation of those genes could be important in the development

  18. Subclassification and Detection of New Markers for the Discrimination of Primary Liver Tumors by Gene Expression Analysis Using Oligonucleotide Arrays.

    Science.gov (United States)

    Hass, Holger G; Vogel, Ulrich; Scheurlen, Michael; Jobst, Jürgen

    2017-12-26

    The failure to correctly differentiate between intrahepatic cholangiocarcinoma [CC] and hepatocellular carcinoma [HCC] is a significant clinical problem, particularly in terms of the different treatment goals for both cancers. In this study a specific gene expression profile to discriminate these two subgroups of liver cancer was established and potential diagnostic markers for clinical use were analyzed. To evaluate the gene expression profiles of HCC and intrahepatic CC, Oligonucleotide arrays ( Affymetrix U133A) were used. Overexpressed genes were checked for their potential use as new markers for discrimination and their expression values were validated by reverse transcription polymerase chain reaction and immunohistochemistry analyses. 695 genes/expressed sequence tags (ESTs) in HCC (245 up-/450 down-regulated) and 552 genes/ESTs in CC (221 up-/331 down-regulated) were significantly dysregulated (p〈0.05, fold change >2, ≥70%). Using a supervised learning method, and one-way analysis of variance a specific 270-gene expression profile that enabled rapid, reproducible differentiation between both tumors and non-malignant liver tissues was established. A panel of 12 genes (e.g. HSP90β, ERG1, GPC3, TKT, ACLY, and NME1 for HCC; SPT2, T4S3, CNX43, TTD1, HBD01 for CC) were detected and partly described for the first time as potential discrimination markers. A specific gene expression profile for discrimination of primary liver cancer was identified and potential marker genes with feasible clinical impact were described.

  19. A Meta-Analysis of Retinoblastoma Copy Numbers Refines the List of Possible Driver Genes Involved in Tumor Progression

    Science.gov (United States)

    Kooi, Irsan E.; Mol, Berber M.; Massink, Maarten P. G.; de Jong, Marcus C.; de Graaf, Pim; van der Valk, Paul; Meijers-Heijboer, Hanne; Kaspers, Gertjan J. L.; Moll, Annette C.; te Riele, Hein; Cloos, Jacqueline; Dorsman, Josephine C.

    2016-01-01

    Background While RB1 loss initiates retinoblastoma development, additional somatic copy number alterations (SCNAs) can drive tumor progression. Although SCNAs have been identified with good concordance between studies at a cytoband resolution, accurate identification of single genes for all recurrent SCNAs is still challenging. This study presents a comprehensive meta-analysis of genome-wide SCNAs integrated with gene expression profiling data, narrowing down the list of plausible retinoblastoma driver genes. Methods We performed SCNA profiling of 45 primary retinoblastoma samples and eight retinoblastoma cell lines by high-resolution microarrays. We combined our data with genomic, clinical and histopathological data of ten published genome-wide SCNA studies, which strongly enhanced the power of our analyses (N = 310). Results Comprehensive recurrence analysis of SCNAs in all studies integrated with gene expression data allowed us to reduce candidate gene lists for 1q, 2p, 6p, 7q and 13q to a limited gene set. Besides the well-established driver genes RB1 (13q-loss) and MYCN (2p-gain) we identified CRB1 and NEK7 (1q-gain), SOX4 (6p-gain) and NUP205 (7q-gain) as novel retinoblastoma driver candidates. Depending on the sample subset and algorithms used, alternative candidates were identified including MIR181 (1q-gain) and DEK (6p gain). Remarkably, our study showed that copy number gains rarely exceeded change of one copy, even in pure tumor samples with 100% homozygosity at the RB1 locus (N = 34), which is indicative for intra-tumor heterogeneity. In addition, profound between-tumor variability was observed that was associated with age at diagnosis and differentiation grades. Interpretation Since focal alterations at commonly altered chromosome regions were rare except for 2p24.3 (MYCN), further functional validation of the oncogenic potential of the described candidate genes is now required. For further investigations, our study provides a refined and revised set

  20. Gene expression profiling of MYC-driven tumor signatures in porcine liver stem cells by transcriptome sequencing.

    Science.gov (United States)

    Aravalli, Rajagopal N; Talbot, Neil C; Steer, Clifford J

    2015-02-21

    To identify the genes induced and regulated by the MYC protein in generating tumors from liver stem cells. In this study, we have used an immortal porcine liver stem cell line, PICM-19, to study the role of c-MYC in hepatocarcinogenesis. PICM-19 cells were converted into cancer cells (PICM-19-CSCs) by overexpressing human MYC. To identify MYC-driven differential gene expression, transcriptome sequencing was carried out by RNA sequencing, and genes identified by this method were validated using real-time PCR. In vivo tumorigenicity studies were then conducted by injecting PICM-19-CSCs into the flanks of immunodeficient mice. Our results showed that MYC-overexpressing PICM-19 stem cells formed tumors in immunodeficient mice demonstrating that a single oncogene was sufficient to convert them into cancer cells (PICM-19-CSCs). By using comparative bioinformatics analyses, we have determined that > 1000 genes were differentially expressed between PICM-19 and PICM-19-CSCs. Gene ontology analysis further showed that the MYC-induced, altered gene expression was primarily associated with various cellular processes, such as metabolism, cell adhesion, growth and proliferation, cell cycle, inflammation and tumorigenesis. Interestingly, six genes expressed by PICM-19 cells (CDO1, C22orf39, DKK2, ENPEP, GPX6, SRPX2) were completely silenced after MYC-induction in PICM-19-CSCs, suggesting that the absence of these genes may be critical for inducing tumorigenesis. MYC-driven genes may serve as promising candidates for the development of hepatocellular carcinoma therapeutics that would not have deleterious effects on other cell types in the liver.

  1. An Inducible Lentiviral Guide RNA Platform Enables the Identification of Tumor-Essential Genes and Tumor-Promoting Mutations In Vivo

    Directory of Open Access Journals (Sweden)

    Brandon J. Aubrey

    2015-03-01

    Full Text Available The CRISPR/Cas9 technology enables the introduction of genomic alterations into almost any organism; however, systems for efficient and inducible gene modification have been lacking, especially for deletion of essential genes. Here, we describe a drug-inducible small guide RNA (sgRNA vector system allowing for ubiquitous and efficient gene deletion in murine and human cells. This system mediates the efficient, temporally controlled deletion of MCL-1, both in vitro and in vivo, in human Burkitt lymphoma cell lines that require this anti-apoptotic BCL-2 protein for sustained survival and growth. Unexpectedly, repeated induction of the same sgRNA generated similar inactivating mutations in the human Mcl-1 gene due to low mutation variability exerted by the accompanying non-homologous end-joining (NHEJ process. Finally, we were able to generate hematopoietic cell compartment-restricted Trp53-knockout mice, leading to the identification of cancer-promoting mutants of this critical tumor suppressor.

  2. Association of tumor necrosis factor-α and -β gene polymorphisms in inflammatory bowel disease

    Directory of Open Access Journals (Sweden)

    Al-Meghaiseeb ES

    2016-06-01

    Full Text Available Ebtissam Saleh Al-Meghaiseeb,1 Abdulrahman A Al-Robayan,1 Mulfi Mubarak Al-Otaibi,1 Misbahul Arfin,2 Abdulrahman K Al-Asmari2 1Department of Gastroenterology, 2Research Centre, Prince Sultan Military Medical City, Riyadh, Saudi Arabia Abstract: Inflammatory bowel disease (IBD is a complex, multifactorial, chronic inflammatory disorder of the gastrointestinal tract in which immune dysregulation caused by genetic and/or environmental factors plays an important role. The aim of this case–­control study was to evaluate the association of tumor necrosis factor-alpha (TNF-α (308 and -β (+252 polymorphisms with susceptibility of IBD. A total of 379 Saudi subjects including 179 IBD patients (ulcerative colitis (UC =84 and Crohn’s disease (CD =95 and 200 age- and sex-matched healthy controls were recruited. TNF-a and TNF-b genes were amplified using an amplification refractory mutation systems polymerase chain reaction methodology to detect TNF-α (–308 and -β (+252 polymorphisms. The frequency of the GA genotype of TNF-α (–308G/A was higher, and the frequencies of the GG and AA genotypes were significantly lower in IBD patients compared with those in controls, indicating that genotype GA-positive individuals are susceptible to IBD and that the GG and AA genotypes exert a protective effect. The frequency of allele A of TNF-α (–308G/A was significantly higher and that of allele G was lower in IBD patients compared with those in controls, indicating an association of allele A with IBD risk in Saudi patients. On stratification of IBD patients into UC and CD, an almost similar pattern was noticed in both the groups. The results of TNF-β (+252A/G polymorphisms showed a significant increase in the frequency of the GG genotype in IBD patients, suggesting a positive association of GG genotype with IBD risk. On stratification of IBD patients into UC and CD, the genotype GG of TNF-β was associated with susceptibility risk to UC but not CD. The

  3. Expression of the Wilms' tumor gene WT1 in the murine urogenital system.

    Science.gov (United States)

    Pelletier, J; Schalling, M; Buckler, A J; Rogers, A; Haber, D A; Housman, D

    1991-08-01

    The Wilms' tumor gene WT1 is a recessive oncogene that encodes a putative transcription factor implicated in nephrogenesis during kidney development. In this report we analyze expression of WT1 in the murine urogenital system. WT1 is expressed in non-germ-cell components of the testis and ovaries in both young and adult mice. In situ mRNA hybridization studies demonstrate that WT1 is expressed in the granulosa and epithelial cells of ovaries, the Sertoli cells of the testis, and in the uterine wall. In addition to the 3.1-kb WT1 transcript detected by Northern blotting of RNA from kidney, uterus, and gonads, there is an approximately 2.5-kb WT1-related mRNA species in testis. The levels of WT1 mRNA in the gonads are among the highest observed, surpassing amounts detected in the embryonic kidney. During development, these levels are differentially regulated, depending on the sexual differentiation of the gonad. Expression of WT1 mRNA in the female reproductive system does not fluctuate significantly from days 4 to 40 postpartum. In contrast, WT1 mRNA levels in the tesis increase steadily after birth, reaching their highest expression levels at day 8 postpartum and decreasing slightly as the animal matures. Expression of WT1 in the gonads is detectable as early as 12.5 days postcoitum (p.c.). As an initial step toward exploring the tissue-specific expression of WT1, DNA elements upstream of WT1 were cloned and sequenced. Three putative transcription initiation sites, utilized in testis, ovaries, and uterus, were mapped by S1 nuclease protection assays. The sequences surrounding these sites have a high G + C content, and typical upstream CCAAT and TATAA boxes are not present. These studies allowed us to identify the translation initiation site for WT1 protein synthesis. We have also used an epitope-tagging protocol to demonstrate that WT1 is a nuclear protein, consistent with its role as a transcription factor. Our results demonstrate regulation of WT1 expression

  4. Caracterização patológica e gênica (gene P53) dos tumores mamários em cadelas.

    OpenAIRE

    Daniela Maria Bastos de Souza

    2006-01-01

    Os tumores mamários em cadelas tem alta incidência e malignidade sendo provocados por vários fatores de risco incluindo idade, atividade hormonal, nutrição, vírus, pseudogestação e administração de progestágenos exógenos. O gene p53, conhecido como um gene supressor de tumor, tem apresentado mutações relacionadas com neoplasias. Neste trabalho, o objetivo foi caracterizar os tumores mamários em cadelas, avaliar o comprometimento da mama lateral ao tumor e o envolvimento de fatores de risco...

  5. Internal radiotherapy of liver cancer with rat hepato-carcinoma-intestine-pancreas gene as a liver tumor-specific promoter

    Energy Technology Data Exchange (ETDEWEB)

    Herve, J.; Cunha, A. Sa; Liu, B.; Valogne, Y.; Longuet, M.; Bregerie, O.; Guettier, C.; Samuel, D.; Brechot, C.; Faivre, J. [Hop Paul Brousse, INSERM, Hepatobiliary Ctr, U785, F-94800 Villejuif (France); Herve, J.; Cunha, A. Sa; Liu, B.; Valogne, Y.; Longuet, M.; Bregerie, O.; Guettier, C.; Samuel, D.; Brechot, C.; Faivre, J. [Univ Paris Sud, Fac Med, F-94800 Villejuif (France); Boisgard, R.; Tavitian, B. [INSERM, U803, F-91400 Orsay (France); Boisgard, R.; Tavitian, B. [CEA, Serv Hosp Frederic Joliot, Lab Imagerie Mol Expt, F-91400 Orsay (France); Roux, J.; Cales, P. [Univ Angers, UPRES EA 3859, Lab Hemodynam Interact Fibrose et Invas Tumorale H, Angers (France); Clerc, J. [Hop Cochin, AP HP, Dept Nucl Med, F-75014 Paris (France)

    2008-07-01

    The hepato-carcinoma-intestine-pancreas (HIP) gene, also called pancreatitis-associated protein-1 (PAP1) or Reg III {alpha}, is activated in most human hepatocellular carcinomas (HCCs) but not in normal liver, which suggests that HIP regulatory sequence could be used as efficient liver tumor-specific promoters to express a therapeutic polynucleotide in liver cancer. The sodium iodide sym-porter (NIS), which has recognized therapeutic and reporter gene properties, is appropriate to evaluate the transcriptional strength and specificity of the HIP promoter in HCC. For this purpose, we constructed a recombinant rat HIP-NIS adeno-viral vector (AdrHIP-NIS), and evaluated its performance as a mediator of selective radio-iodide uptake in tumor hepatocytes. Western blot, immunofluorescence, and iodide uptake assays were performed in AdrHIP-NIS-infected primary hepatocytes and transformed hepatic and non-hepatic cells. Nuclear imaging, tissue counting and immuno-histo-chemistry were performed in normal and HCC-bearing Wistar rats infected with AdrHIP-NIS intra-tumorally or via the hepatic artery. In AdrHIP-NIS-infected transformed hepatic cells, functional NIS was strongly expressed, as in cells infected with a cytomegalovirus-NIS vector. No NIS expression was found in AdrHIP-NIS-infected normal hepatocytes or transformed non-hepatic cells. In rats bearing multi-nodular HCC, AdrHIP-NIS triggered functional NIS expression that was preferential in tumor hepatocytes. Administration of 18 mCi of {sup 131}I resulted in the destruction of AdrHIP-NIS-injected nodules. This study has identified the rHIP regulatory sequence as a potent liver tumor-specific promoter for the transfer of therapeutic genes, and AdrHIP-NIS-mediated. {sup 131}I therapy as a valuable option for the treatment of multi-nodular HCC. (authors)

  6. Functional interactions between the erupted/tsg101 growth suppressor gene and the DaPKC and rbf1 genes in Drosophila imaginal disc tumors.

    Directory of Open Access Journals (Sweden)

    M Melissa Gilbert

    Full Text Available BACKGROUND: The Drosophila gene erupted (ept encodes the fly homolog of human Tumor Susceptibility Gene-101 (TSG101, which functions as part of the conserved ESCRT-1 complex to facilitate the movement of cargoes through the endolysosomal pathway. Loss of ept or other genes that encode components of the endocytic machinery (e.g. synatxin7/avalanche, rab5, and vps25 produces disorganized overgrowth of imaginal disc tissue. Excess cell division is postulated to be a primary cause of these 'neoplastic' phenotypes, but the autonomous effect of these mutations on cell cycle control has not been examined. PRINCIPAL FINDINGS: Here we show that disc cells lacking ept function display an altered cell cycle profile indicative of deregulated progression through the G1-to-S phase transition and express reduced levels of the tumor suppressor ortholog and G1/S inhibitor Rbf1. Genetic reductions of the Drosophila aPKC kinase (DaPKC, which has been shown to promote tumor growth in other fly tumor models, prevent both the ept neoplastic phenotype and the reduction in Rbf1 levels that otherwise occurs in clones of ept mutant cells; this effect is coincident with changes in localization of Notch and Crumbs, two proteins whose sorting is altered in ept mutant cells. The effect on Rbf1 can also be blocked by removal of the gamma-secretase component presenilin, suggesting that cleavage of a gamma-secretase target influences Rbf1 levels in ept mutant cells. Expression of exogenous rbf1 completely ablates ept mutant eye tissues but only mildly affects the development of discs composed of cells with wild type ept. CONCLUSIONS: Together, these data show that loss of ept alters nuclear cell cycle control in developing imaginal discs and identify the DaPKC, presenilin, and rbf1 genes as modifiers of molecular and cellular phenotypes that result from loss of ept.

  7. Synergistic tumor-cidal effect of combination of hMUC1 vaccination and hNIS radioiodine gene therapy

    International Nuclear Information System (INIS)

    Jeon, Yong Hyun; Choi, Yun; Kim, Chul Woo; Jeong, Jae Min; Lee, Dong Soo; Chung, June Key

    2007-01-01

    We developed the combination therapy of hMUC1 vaccination and hNlS radioiodine gene therapy in tumor bearing mice and visualized the anti-tumor effect using molecular imaging. A stable colon cancer cell line (CT26/hMUC1-hNlS-Fluc: CMNF) expressing the hMUC1, hNlS, and Flue genes was established. The in vitro survival rates of CMNF were determined using clonogenic assay after I-131 treatment. Five groups of 28 Balb/c (7mice/group) mice were made after subcutaneously injection of CMNF cells according to treatments (pcDNA3.1+PBS, phMUC1+PBS, pcDNA3.1+I-131, and phMUC1+I-131 groups). After development of xenografted tumor, PBS, MUC1 vaccine, I-131, and MUC1 vaccine + I-131 were administered to the mice. Tumor progression was monitored by using a bioluminescent image and caliper. Thirty-two days after tumor transplantation, we re-challenged CMNF to pcDNA3.1+I-131, and phMUC1 +I-131 groups. We investigated the number of hMUC1-associated CD8+IFN-+ T cells and of cytotoxic T cells (CTLs) activity using splenocytes in treated mice. The in vitro survival rate of CMNF was significantly reduced to 15.31.1 % after I-131 treatment compared with the survival rates of parental cells (p<0.001). Complete tumor growth inhibition was shown in phMUC1+ I-131 group at 48 days post challenge, but not in any monotherapy group (p<0.05). In cases of tumor rechallenging, complete rejection of the tumor occurred in phMUC1 + I-131 group, but not in pcDNA3.1 + I-131 group. The number of hMUC1-associated CD8+ IFN-+ T cells was significantly more increased in phMUC1 +I-131 group compared mono-therapy group (P<0.001). The activity of hMUC1-associated CTLs in was higher than those of monotherapy groups (P<0.005). We found that this combination therapy induced the complete remission, and rejected rechallenged tumor cells in murine colon cancer model. This novel combination therapy strategy has a possibility to be applied in clinical oncology

  8. A nanocomplex that is both tumor cell-selective and cancer gene-specific for anaplastic large cell lymphoma

    Directory of Open Access Journals (Sweden)

    Zu Youli

    2011-01-01

    Full Text Available Abstract Background Many in vitro studies have demonstrated that silencing of cancerous genes by siRNAs is a potential therapeutic approach for blocking tumor growth. However, siRNAs are not cell type-selective, cannot specifically target tumor cells, and therefore have limited in vivo application for siRNA-mediated gene therapy. Results In this study, we tested a functional RNA nanocomplex which exclusively targets and affects human anaplastic large cell lymphoma (ALCL by taking advantage of the abnormal expression of CD30, a unique surface biomarker, and the anaplastic lymphoma kinase (ALK gene in lymphoma cells. The nanocomplexes were formulated by incorporating both ALK siRNA and a RNA-based CD30 aptamer probe onto nano-sized polyethyleneimine-citrate carriers. To minimize potential cytotoxicity, the individual components of the nanocomplexes were used at sub-cytotoxic concentrations. Dynamic light scattering showed that formed nanocomplexes were ~140 nm in diameter and remained stable for more than 24 hours in culture medium. Cell binding assays revealed that CD30 aptamer probes selectively targeted nanocomplexes to ALCL cells, and confocal fluorescence microscopy confirmed intracellular delivery of the nanocomplex. Cell transfection analysis showed that nanocomplexes silenced genes in an ALCL cell type-selective fashion. Moreover, exposure of ALCL cells to nanocomplexes carrying both ALK siRNAs and CD30 RNA aptamers specifically silenced ALK gene expression, leading to growth arrest and apoptosis. Conclusions Taken together, our findings indicate that this functional RNA nanocomplex is both tumor cell type-selective and cancer gene-specific for ALCL cells.

  9. Human umbilical cord matrix mesenchymal stem cells suppress the growth of breast cancer by expression of tumor suppressor genes.

    Directory of Open Access Journals (Sweden)

    Naomi Ohta

    Full Text Available Human and rat umbilical cord matrix mesenchymal stem cells (UCMSC possess the ability to control the growth of breast carcinoma cells. Comparative analyses of two types of UCMSC suggest that rat UCMSC-dependent growth regulation is significantly stronger than that of human UCMSC. Their different tumoricidal abilities were clarified by analyzing gene expression profiles in the two types of UCMSC. Microarray analysis revealed differential gene expression between untreated naïve UCMSC and those co-cultured with species-matched breast carcinoma cells. The analyses screened 17 differentially expressed genes that are commonly detected in both human and rat UCMSC. The comparison between the two sets of gene expression profiles identified two tumor suppressor genes, adipose-differentiation related protein (ADRP and follistatin (FST, that were specifically up-regulated in rat UCMSC, but down-regulated in human UCMSC when they were co-cultured with the corresponding species' breast carcinoma cells. Over-expression of FST, but not ADRP, in human UCMSC enhanced their ability to suppress the growth of MDA-231 cells. The growth of MDA-231 cells was also significantly lower when they were cultured in medium conditioned with FST, but not ADRP over-expressing human UCMSC. In the breast carcinoma lung metastasis model generated with MDA-231 cells, systemic treatment with FST-over-expressing human UCMSC significantly attenuated the tumor burden. These results suggest that FST may play an important role in exhibiting stronger tumoricidal ability in rat UCMSC than human UCMSC and also implies that human UCMSC can be transformed into stronger tumoricidal cells by enhancing tumor suppressor gene expression.

  10. Gene Expression Ratios Lead to Accurate and Translatable Predictors of DR5 Agonism across Multiple Tumor Lineages.

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    Anupama Reddy

    Full Text Available Death Receptor 5 (DR5 agonists demonstrate anti-tumor activity in preclinical models but have yet to demonstrate robust clinical responses. A key limitation may be the lack of patient selection strategies to identify those most likely to respond to treatment. To overcome this limitation, we screened a DR5 agonist Nanobody across >600 cell lines representing 21 tumor lineages and assessed molecular features associated with response. High expression of DR5 and Casp8 were significantly associated with sensitivity, but their expression thresholds were difficult to translate due to low dynamic ranges. To address the translational challenge of establishing thresholds of gene expression, we developed a classifier based on ratios of genes that predicted response across lineages. The ratio classifier outperformed the DR5+Casp8 classifier, as well as standard approaches for feature selection and classification using genes, instead of ratios. This classifier was independently validated using 11 primary patient-derived pancreatic xenograft models showing perfect predictions as well as a striking linearity between prediction probability and anti-tumor response. A network analysis of the genes in the ratio classifier captured important biological relationships mediating drug response, specifically identifying key positive and negative regulators of DR5 mediated apoptosis, including DR5, CASP8, BID, cFLIP, XIAP and PEA15. Importantly, the ratio classifier shows translatability across gene expression platforms (from Affymetrix microarrays to RNA-seq and across model systems (in vitro to in vivo. Our approach of using gene expression ratios presents a robust and novel method for constructing translatable biomarkers of compound response, which can also probe the underlying biology of treatment response.

  11. Radiation-associated breast tumors display a distinct gene expression profile

    DEFF Research Database (Denmark)

    Broeks, Annegien; Braaf, Linde M; Wessels, Lodewyk F A

    2010-01-01

    PURPOSE: Women who received irradiation for Hodgkin's lymphoma have a strong increased risk for developing breast cancer. Approximately 90% of the breast cancers in these patients can be attributed to their radiation treatment, rendering such series extremely useful to determine whether a common...... separate from the control tumors (p centroid classifier of 198 probes was identified. The BfHL tumors were often of the intrinsic basal breast tumor subtype, and they showed a chromosomal instability profile and a higher expression...

  12. Gene Expression of Glucose Transporter 1 (GLUT1), Hexokinase 1 and Hexokinase 2 in Gastroenteropancreatic Neuroendocrine Tumors

    DEFF Research Database (Denmark)

    Binderup, Tina; Knigge, Ulrich; Federspiel, Birgitte Hartnack

    2013-01-01

    Neoplastic tissue exhibits high glucose utilization and over-expression of glucose transporters (GLUTs) and hexokinases (HKs), which can be imaged by (18)F-Fluorodeoxyglucose-positron emission tomography (FDG-PET). The aim of the present study was to investigate the expression of glycolysis......-associated genes and to compare this with FDG-PET imaging as well as with the cellular proliferation index in two cancer entities with different malignant potential. Using real-time PCR, gene expression of GLUT1, HK1 and HK2 were studied in 34 neuroendocrine tumors (NETs) in comparison with 14 colorectal...... adenocarcinomas (CRAs). The Ki67 proliferation index and, when available, FDG-PET imaging was compared with gene expression. Overexpression of GLUT1 gene expression was less frequent in NETs (38%) compared to CRAs (86%), P = 0.004. HK1 was overexpressed in 41% and 71% of NETs and CRAs, respectively (P = 0...

  13. ALK Gene Translocation in Inflammatory Myofibroblastic Tumor of the Urinary Bladder: A Case Report

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    Kimiaki Takagi

    2015-09-01

    Full Text Available A 26-year-old woman with gross hematuria was seen in a previous hospital. Magnetic resonance imaging (MRI showed a tumor at the dome of the urinary bladder with invasion outside of the bladder wall. The patient underwent transurethral resection of the bladder tumor (TUR-BT. From the result of the pathological examination, the tumor was suggested to be carcinosarcoma of the bladder. The patient was then referred to our hospital for treatment. We performed radical cystectomy and ileal conduit diversion. Pathological examination of the excised specimen revealed an inflammatory myofibroblastic tumor as the basis for immunostaining of anaplastic lymphoma kinase (ALK.

  14. Lack of mutations in the TP53 tumor suppressor gene exons 5 to 8 in Fanconi's anemia.

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    Jonveaux, P; Le Coniat, M; Grausz, D; Berger, R

    1991-01-01

    The TP53 gene is considered to be a negative regulator of cell growth whose inactivation is an important step in the development or progression of malignancies. Recently, germ line TP53 mutations have been detected in a familial cancer syndrome, the dominantly inherited Li-Fraumeni syndrome. Using single strand conformation polymorphism analysis of PCR products, we looked for TP53 mutations in DNA of patients with Fanconi anemia, an autosomal recessive disease characterized by increased predisposition to neoplasia. We did not find any TP53 mutation in 13 patients, suggesting that this tumor suppressor gene is not directly involved in the cancer susceptibility observed in Fanconi's anemia.

  15. Enhanced gene expression in tumors after intravenous administration of arginine-, lysine- and leucine-bearing polypropylenimine polyplex.

    Science.gov (United States)

    Aldawsari, Hibah; Edrada-Ebel, Ruangelie; Blatchford, David R; Tate, Rothwelle J; Tetley, Laurence; Dufès, Christine

    2011-09-01

    The possibility of using non-viral gene delivery systems for the treatment of cancer is currently limited by their lower transfection efficacy compared to viral systems. On the basis that amino acids such as arginine, lysine and leucine were involved in enhancing DNA transportation into cells, we hypothesized that the grafting of these amino acids to the highly promising generation 3 diaminobutyric polypropylenimine (DAB) dendrimer would improve its transfection efficacy in cancer cells. In this work we demonstrated that the conjugation of arginine, lysine and leucine to the dendrimer led to an enhanced anti-proliferative activity of the polyplexes, by up to 47-fold for DAB-Lys in T98G cancer cells compared to the unmodified polyplex in vitro. In vivo, the intravenous administration of amino acid-bearing DAB polyplexes resulted in a significantly improved tumor gene expression, with the highest gene expression level observed after treatment with DAB-Lys polyplex. Arginine, lysine and leucine-bearing generation 3 polypropylenimine polymers are therefore highly promising gene delivery systems for gene transfection in tumors. Copyright © 2011 Elsevier Ltd. All rights reserved.

  16. Coupled Transcriptome and Proteome Analysis of Human Lymphotropic Tumor Viruses: Insights on the Detection and Discovery of Viral Genes

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    Dresang, Lindsay R.; Teuton, Jeremy R.; Feng, Huichen; Jacobs, Jon M.; Camp, David G.; Purvine, Samuel O.; Gritsenko, Marina A.; Li, Zhihua; Smith, Richard D.; Sugden, Bill; Moore, Patrick S.; Chang, Yuan

    2011-12-20

    Kaposi's sarcoma-associated herpesvirus (KSHV) and Epstein-Barr virus (EBV) are related human tumor viruses that cause primary effusion lymphomas (PEL) and Burkitt's lymphomas (BL), respectively. Viral genes expressed in naturally-infected cancer cells contribute to disease pathogenesis; knowing which viral genes are expressed is critical in understanding how these viruses cause cancer. To evaluate the expression of viral genes, we used high-resolution separation and mass spectrometry coupled with custom tiling arrays to align the viral proteomes and transcriptomes of three PEL and two BL cell lines under latent and lytic culture conditions. Results The majority of viral genes were efficiently detected at the transcript and/or protein level on manipulating the viral life cycle. Overall the correlation of expressed viral proteins and transcripts was highly complementary in both validating and providing orthogonal data with latent/lytic viral gene expression. Our approach also identified novel viral genes in both KSHV and EBV, and extends viral genome annotation. Several previously uncharacterized genes were validated at both transcript and protein levels. Conclusions This systems biology approach coupling proteome and transcriptome measurements provides a comprehensive view of viral gene expression that could not have been attained using each methodology independently. Detection of viral proteins in combination with viral transcripts is a potentially powerful method for establishing virus-disease relationships.

  17. Gene expression markers in circulating tumor cells may predict bone metastasis and response to hormonal treatment in breast cancer.

    Science.gov (United States)

    Wang, Haiying; Molina, Julian; Jiang, John; Ferber, Matthew; Pruthi, Sandhya; Jatkoe, Timothy; Derecho, Carlo; Rajpurohit, Yashoda; Zheng, Jian; Wang, Yixin

    2013-11-01

    Circulating tumor cells (CTCs) have recently attracted attention due to their potential as prognostic and predictive markers for the clinical management of metastatic breast cancer patients. The isolation of CTCs from patients may enable the molecular characterization of these cells, which may help establish a minimally invasive assay for the prediction of metastasis and further optimization of treatment. Molecular markers of proven clinical value may therefore be useful in predicting disease aggressiveness and response to treatment. In our earlier study, we identified a gene signature in breast cancer that appears to be significantly associated with bone metastasis. Among the genes that constitute this signature, trefoil factor 1 (TFF1) was identified as the most differentially expressed gene associated with bone metastasis. In this study, we investigated 25 candidate gene markers in the CTCs of metastatic breast cancer patients with different metastatic sites. The panel of the 25 markers was investigated in 80 baseline samples (first blood draw of CTCs) and 30 follow-up samples. In addition, 40 healthy blood donors (HBDs) were analyzed as controls. The assay was performed using quantitative reverse transcriptase polymerase chain reaction (qRT-PCR) with RNA extracted from CTCs captured by the CellSearch system. Our study indicated that 12 of the genes were uniquely expressed in CTCs and 10 were highly expressed in the CTCs obtained from patients compared to those obtained from HBDs. Among these genes, the expression of keratin 19 was highly correlated with the CTC count. The TFF1 expression in CTCs was a strong predictor of bone metastasis and the patients with a high expression of estrogen receptor β in CTCs exhibited a better response to hormonal treatment. Molecular characterization of these genes in CTCs may provide a better understanding of the mechanism underlying tumor metastasis and identify gene markers in CTCs for predicting disease progression and

  18. Immunotherapy with Dendritic Cells Modified with Tumor-Associated Antigen Gene Demonstrates Enhanced Antitumor Effect Against Lung Cancer

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    Tao Jiang

    2017-04-01

    Full Text Available BACKGROUND: Immunotherapy using dendritic cell (DC vaccine has the potential to overcome the bottleneck of cancer therapy. METHODS: We engineered Lewis lung cancer cells (LLCs and bone marrow–derived DCs to express tumor-associated antigen (TAA ovalbumin (OVA via lentiviral vector plasmid encoding OVA gene. We then tested the antitumor effect of modified DCs both in vitro and in vivo. RESULTS: The results demonstrated that in vitro modified DCs could dramatically enhance T-cell proliferation (P < .01 and killing of LLCs than control groups (P < .05. Moreover, modified DCs could reduce tumor size and prolong the survival of LLC tumor-bearing mice than control groups (P < .01 and P < .01, respectively. Mechanistically, modified DCs demonstrated enhanced homing to T-cell–rich compartments and triggered more naive T cells to become cytotoxic T lymphocytes, which exhibited significant infiltration into the tumors. Interestingly, modified DCs also markedly reduced tumor cells harboring stem cell markers in mice (P < .05, suggesting the potential role on cancer stem-like cells. CONCLUSION: These findings suggested that DCs bioengineered with TAA could enhance antitumor effect and therefore represent a novel anticancer strategy that is worth further exploration.

  19. Overexpression of Wilms Tumor 1 Gene as a Negative Prognostic Indicator in Acute Myeloid Leukemia

    Science.gov (United States)

    Mi, Ruihua; Ding, Jing; Wang, Xianwei; Hu, Jieying; Fan, Ruihua; Wei, Xudong; Song, Yongping; Zhao, Richard Y.

    2014-01-01

    Chromosomal aberrations are useful in assessing treatment options and clinical outcomes of acute myeloid leukemia (AML) patients. However, 40∼50% of the AML patients showed no chromosomal abnormalities, i.e., with normal cytogenetics aka the CN-AML patients. Testing of molecular aberrations such as FLT3 or NPM1 can help to define clinical outcomes in the CN-AML patients but with various successes. Goal of this study was to test the possibility of Wilms’ tumor 1 (WT1) gene overexpression as an additional molecular biomarker. A total of 103 CN-AML patients, among which 28% had overexpressed WT1, were studied over a period of 38 months. Patient’s response to induction chemotherapy as measured by the complete remission (CR) rate, disease-free survival (DFS) and overall survival (OS) were measured. Our data suggested that WT1 overexpression correlated negatively with the CR rate, DFS and OS. Consistent with previous reports, CN-AML patients can be divided into three different risk subgroups based on the status of known molecular abnormalities, i.e., the favorable (NPM1mt/no FLT3ITD), the unfavorable (FLT3ITD) and the intermediate risk subgroups. The WT1 overexpression significantly reduced the CR, DFS and OS in both the favorable and unfavorable groups. As the results, patients with normal WT1 gene expression in the favorable risk group showed the best clinical outcomes and all survived with complete remission and disease-free survival over the 37 month study period; in contrast, patients with WT1 overexpression in the unfavorable risk group displayed the worst clinical outcomes. WT1 overexpression by itself is an independent and negative indicator for predicting CR rate, DFS and OS of the CN-AML patients; moreover, it increases the statistical power of predicting the same clinical outcomes when it is combined with the NPM1 mt or the FLT3 ITD genotypes that are the good or poor prognostic markers of CN-AML. PMID:24667279

  20. Atheroprotective Effects of Tumor Necrosis Factor–Stimulated Gene-6

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    Rena Watanabe, MS

    2016-10-01

    Full Text Available Tumor necrosis factor–stimulated gene-6 (TSG-6, an anti-inflammatory protein, was shown to be localized in the neointima of injury-induced rat arteries. However, the modulatory effect of TSG-6 on atherogenesis has not yet been reported. We aimed to evaluate the atheroprotective effects of TSG-6 on human endothelial cells (HECs, human monocyte-derived macrophages (HMDMs, human aortic smooth muscle cells (HASMCs in vitro, and aortic lesions in apolipoprotein E–deficient mice, along with expression levels of TSG-6 in coronary lesions and plasma from patients with coronary artery disease (CAD. TSG-6 was abundantly expressed in HECs, HMDMs, and HASMCs in vitro. TSG-6 significantly suppressed cell proliferation and lipopolysaccharide-induced up-regulation of monocyte chemotactic protein-1, intercellular adhesion molecule-1, and vascular adhesion molecule-1 in HECs. TSG-6 significantly suppressed inflammatory M1 phenotype and suppressed oxidized low-density lipoprotein–induced foam cell formation associated with down-regulation of CD36 and acyl-CoA:cholesterol acyltransferase-1 in HMDMs. In HASMCs, TSG-6 significantly suppressed migration and proliferation, but increased collagen-1 and -3 expressions. Four-week infusion of TSG-6 into apolipoprotein E–deficient mice significantly retarded the development of aortic atherosclerotic lesions with decreased vascular inflammation, monocyte/macrophage, and SMC contents and increased collagen fibers. In addition, it decreased peritoneal M1 macrophages with down-regulation of inflammatory molecules and lowered plasma total cholesterol levels. In patients with CAD, plasma TSG-6 levels were significantly increased, and TSG-6 was highly expressed in the fibrous cap within coronary atherosclerotic plaques. These results suggest that TSG-6 contributes to the prevention and stability of atherosclerotic plaques. Thus, TSG-6 may serve as a novel therapeutic target for CAD.

  1. Improving the prediction of chemotherapeutic sensitivity of tumors in breast cancer via optimizing the selection of candidate genes.

    Science.gov (United States)

    Jiang, Lina; Huang, Liqiu; Kuang, Qifan; Zhang, Juan; Li, Menglong; Wen, Zhining; He, Li

    2014-04-01

    Estrogen receptor status and the pathologic response to preoperative chemotherapy are two important indicators of chemotherapeutic sensitivity of tumors in breast cancer, which are used to guide the selection of specific regimens for patients. Microarray-based gene expression profiling, which is successfully applied to the discovery of tumor biomarkers and the prediction of drug response, was suggested to predict the cancer outcomes using the gene signatures differentially expressed between two clinical states. However, many false positive genes unrelated to the phenotypic differences will be involved in the lists of differentially expressed genes (DEGs) when only using the statistical methods for gene selection, e.g. Student's t test, and subsequently affect the performance of the predictive models. For the purpose of improving the prediction of clinical outcomes, we optimized the selection of DEGs by using a combined strategy, for which the DEGs were firstly identified by the statistical methods, and then filtered by a similarity profiling approach that used for candidate gene prioritization. In our study, we firstly verified the molecular functions of the DEGs identified by the combined strategy with the gene expression data generated in the microarray experiments of Si-Wu-Tang, which is a popular formula in traditional Chinese medicine. The results showed that, for Si-Wu-Tang experimental data set, the cancer-related signaling pathways were significantly enriched by gene set enrichment analysis when using the DEG lists generated by the combined strategy, confirming the potentially cancer-preventive effect of Si-Wu-Tang. To verify the performance of the predictive models in clinical application, we used the combined strategy to select the DEGs as features from the gene expression data of the clinical samples, which were collected from the breast cancer patients, and constructed models to predict the chemotherapeutic sensitivity of tumors in breast cancer. After

  2. Building a Robust Tumor Profiling Program: Synergy between Next-Generation Sequencing and Targeted Single-Gene Testing.

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    Matthew C Hiemenz

    Full Text Available Next-generation sequencing (NGS is a powerful platform for identifying cancer mutations. Routine clinical adoption of NGS requires optimized quality control metrics to ensure accurate results. To assess the robustness of our clinical NGS pipeline, we analyzed the results of 304 solid tumor and hematologic malignancy specimens tested simultaneously by NGS and one or more targeted single-gene tests (EGFR, KRAS, BRAF, NPM1, FLT3, and JAK2. For samples that passed our validated tumor percentage and DNA quality and quantity thresholds, there was perfect concordance between NGS and targeted single-gene tests with the exception of two FLT3 internal tandem duplications that fell below the stringent pre-established reporting threshold but were readily detected by manual inspection. In addition, NGS identified clinically significant mutations not covered by single-gene tests. These findings confirm NGS as a reliable platform for routine clinical use when appropriate quality control metrics, such as tumor percentage and DNA quality cutoffs, are in place. Based on our findings, we suggest a simple workflow that should facilitate adoption of clinical oncologic NGS services at other institutions.

  3. Building a Robust Tumor Profiling Program: Synergy between Next-Generation Sequencing and Targeted Single-Gene Testing.

    Science.gov (United States)

    Hiemenz, Matthew C; Kadauke, Stephan; Lieberman, David B; Roth, David B; Zhao, Jianhua; Watt, Christopher D; Daber, Robert D; Morrissette, Jennifer J D

    2016-01-01

    Next-generation sequencing (NGS) is a powerful platform for identifying cancer mutations. Routine clinical adoption of NGS requires optimized quality control metrics to ensure accurate results. To assess the robustness of our clinical NGS pipeline, we analyzed the results of 304 solid tumor and hematologic malignancy specimens tested simultaneously by NGS and one or more targeted single-gene tests (EGFR, KRAS, BRAF, NPM1, FLT3, and JAK2). For samples that passed our validated tumor percentage and DNA quality and quantity thresholds, there was perfect concordance between NGS and targeted single-gene tests with the exception of two FLT3 internal tandem duplications that fell below the stringent pre-established reporting threshold but were readily detected by manual inspection. In addition, NGS identified clinically significant mutations not covered by single-gene tests. These findings confirm NGS as a reliable platform for routine clinical use when appropriate quality control metrics, such as tumor percentage and DNA quality cutoffs, are in place. Based on our findings, we suggest a simple workflow that should facilitate adoption of clinical oncologic NGS services at other institutions.

  4. The Role of HLA-G Molecule and HLA-G Gene Polymorphisms in Tumors, Viral Hepatitis, and Parasitic Diseases.

    Science.gov (United States)

    Dias, Fabrício C; Castelli, Erick C; Collares, Cristhianna V A; Moreau, Philippe; Donadi, Eduardo A

    2015-01-01

    Considering that the non-classical HLA-G molecule has well-recognized tolerogenic properties, HLA-G expression is expected to be deleterious when present in tumor cells and in cells chronically infected by viruses, whereas HLA-G expression is expected to be advantageous in autoimmune disorders. The expression of HLA-G on tissue or peripheral blood cells, the levels of soluble HLA-G and polymorphic sites along the gene have been studied in several disorders. In this study, we revised the role of the molecule and polymorphic sites along the HLA-G gene in tumors, viral hepatitis, and parasitic disorders. Overall, several lines of evidence clearly show that the induction of HLA-G expression in tumors has been associated with worse disease outcome and disease spread. In addition, the few studies conducted on hepatitis and parasitic disorders indicate that HLA-G may contribute to disease pathogenesis. Few isolated polymorphic sites, primarily located at the coding or 3' untranslated HLA-G region, have been evaluated in these disorders, and a complete HLA-G typing together with the study of gene regulatory elements may further help on the understanding of the influence of the genetic background on disease susceptibility.

  5. Association between mutations of critical pathway genes and survival outcomes according to the tumor location in colorectal cancer.

    Science.gov (United States)

    Lee, Dae-Won; Han, Sae-Won; Cha, Yongjun; Bae, Jeong Mo; Kim, Hwang-Phill; Lyu, Jaemyun; Han, Hyojun; Kim, Hyoki; Jang, Hoon; Bang, Duhee; Huh, Iksoo; Park, Taesung; Won, Jae-Kyung; Jeong, Seung-Yong; Park, Kyu Joo; Kang, Gyeong Hoon; Kim, Tae-You

    2017-09-15

    Colorectal cancer (CRC) develops through the alteration of several critical pathways. This study was aimed at evaluating the influence of critical pathways on survival outcomes for patients with CRC. Targeted next-generation sequencing of 40 genes included in the 5 critical pathways of CRC (WNT, P53, RTK-RAS, phosphatidylinositol-4,5-bisphosphate 3-kinase [PI3K], and transforming growth factor β [TGF-β]) was performed for 516 patients with stage III or high-risk stage II CRC treated with surgery followed by adjuvant fluoropyrimidine and oxaliplatin chemotherapy. The associations between critical pathway mutations and relapse-free survival (RFS) and overall survival were analyzed. The associations were further analyzed according to the tumor location. The mutation rates for the WNT, P53, RTK-RAS, PI3K, and TGF-β pathways were 84.5%, 69.0%, 60.7%, 30.0%, and 28.9%, respectively. A mutation in the PI3K pathway was associated with longer RFS (adjusted hazard ratio [HR], 0.59; 95% confidence interval [CI], 0.36-0.99), whereas a mutation in the RTK-RAS pathway was associated with shorter RFS (adjusted HR, 1.60; 95% CI, 1.01-2.52). Proximal tumors showed a higher mutation rate than distal tumors, and the mutation profile was different according to the tumor location. The mutation rates of Kirsten rat sarcoma viral oncogene homolog (KRAS), phosphatidylinositol-4,5-bisphosphate 3-kinase catalytic subunit α (PIK3CA), and B-Raf proto-oncogene serine/threonine kinase (BRAF) were higher in proximal tumors, and the mutation rates of adenomatous polyposis coli (APC), tumor protein 53 (TP53), and neuroblastoma RAS viral oncogene homolog (NRAS) were higher in distal tumors. The better RFS with the PI3K pathway mutation was significant only for proximal tumors, and the worse RFS with the RTK-RAS pathway mutation was significant only for distal tumors. A PI3K pathway mutation was associated with better RFS for CRC patients treated with adjuvant chemotherapy, and an RTK

  6. Intraperitoneal administration of a tumor-associated antigen SART3, CD40L, and GM-CSF gene-loaded polyplex micelle elicits a vaccine effect in mouse tumor models.

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    Kouichi Furugaki

    Full Text Available Polyplex micelles have demonstrated biocompatibility and achieve efficient gene transfection in vivo. Here, we investigated a polyplex micelle encapsulating genes encoding the tumor-associated antigen squamous cell carcinoma antigen recognized by T cells-3 (SART3, adjuvant CD40L, and granulocyte macrophage colony-stimulating factor (GM-CSF as a DNA vaccine platform in mouse tumor models with different types of major histocompatibility antigen complex (MHC. Intraperitoneally administrated polyplex micelles were predominantly found in the lymph nodes, spleen, and liver. Compared with mock controls, the triple gene vaccine significantly prolonged the survival of mice harboring peritoneal dissemination of CT26 colorectal cancer cells, of which long-term surviving mice showed complete rejection when re-challenged with CT26 tumors. Moreover, the DNA vaccine inhibited the growth and metastasis of subcutaneous CT26 and Lewis lung tumors in BALB/c and C57BL/6 mice, respectively, which represent different MHC haplotypes. The DNA vaccine highly stimulated both cytotoxic T lymphocyte and natural killer cell activities, and increased the infiltration of CD11c+ DCs and CD4+/CD8a+ T cells into tumors. Depletion of CD4+ or CD8a+ T cells by neutralizing antibodies deteriorated the anti-tumor efficacy of the DNA vaccine. In conclusion, a SART3/CD40L+GM-CSF gene-loaded polyplex micelle can be applied as a novel vaccine platform to elicit tumor rejection immunity regardless of the recipient MHC haplotype.

  7. [Oncopathological aspects of BRCA1 and BRCA2 genes inactivation in tumors of ovary, fallopian tube and pelvic peritoneum].

    Science.gov (United States)

    Škapa, Petr; Dundr, Pavel

    2016-01-01

    Ovarian carcinoma represents a heterogeneous group of malignant epithelial tumors which could be divided into two fundamental groups: Type I (endometrioid carcinoma, clear cell carcinoma, low grade serous carcinoma, mucinous carcinoma and more rare seromucinous carcinoma and malignant Brenner tumor) and type II (high grade serous carcinoma - HGSC). HGSC is the most frequent ovarian carcinoma which may be etiologically linked to inactivation of tumor suppressor genes BRCA1/2 and TP53 and differs from type I carcinomas by higher aggressiveness, tendency to peritoneal spread and worse prognosis. A precursor lesion of HGSC was described as a serous tubal intraepithelial carcinoma (STIC) which is usually localized in fimbria of the fallopian tube from where tumor cells are capable to implant on ovary and pelvic peritoneum. Therefore, HGSC may present itself not only as a tuboovarian tumor but also as a primary peritoneal carcinoma. HGSC constitutes a dominant group within hereditary ovarian carcinomas as a manifestation of hereditary breast and ovarian cancer or site-specific ovarian cancer syndromes which are associated with germinal mutations of BRCA1/2 genes. BRCA1 deficient HGSC show characteristic histological appearance which encompasses SET features (Solid-pseudoEndometrioid-Transitional), significant nuclear atypia and mitotic activity, geographic necrosis, marked lymphocytic infiltration and abnormalities in TP53 expression. Use of immunohistochemistry as a screening method for BRCA1/2 inactivation is questionable at this time. Bilateral adnexectomy is considered to be a standard prophylactic treatment of women affected by germinal BRCA1/2 mutation. In that case, fallopian tubes should be submitted completely for the histological evaluation according to the SEE-FIM protocol (Sectioning and Extensively Examining the FIMbria) due to the risk of STIC or occult HGSC. Tumors with BRCA1/2 inactivation show a better therapeutic response to platinum

  8. Breast tumor characteristics of BRCA1 and BRCA2 gene mutation carriers on MRI.

    NARCIS (Netherlands)

    Veltman, J.; Mann, R.; Kok, T.; Obdeijn, I.M.; Hoogerbrugge-van der Linden, N.; Blickman, J.G.; Boetes, C.

    2008-01-01

    The appearance of malignant lesions in BRCA1 and BRCA2 mutation carriers (BRCA-MCs) on mammography and magnetic resonance imaging (MRI) was evaluated. Thus, 29 BRCA-MCs with breast cancer were retrospectively evaluated and the results compared with an age, tumor size and tumor type matched control

  9. Breast tumor characteristics of BRCA1 and BRCA2 gene mutation carriers on MRI

    NARCIS (Netherlands)

    Veltman, J.; Mann, R.; Kok, T.; Obdeijn, I. M.; Hoogerbrugge, N.; Blickman, J. G.; Boetes, C.

    The appearance of malignant lesions in BRCA1 and BRCA2 mutation carriers (BRCA-MCs) on mammography and magnetic resonance imaging (MRI) was evaluated. Thus, 29 BRCA-MCs with breast cancer were retrospectively evaluated and the results compared with an age, tumor size and tumor type matched control

  10. Breast tumor characteristics of BRCA1 and BRCA2 gene mutation carriers on MRI

    NARCIS (Netherlands)

    J. Veltman; R. Mann; T. Kok (Theo); A.I.M. Obdeijn (Inge-Marie); N. Hoogerbrugge (Nicoline); J.G. Blickman; C. Boetes (Carla)

    2008-01-01

    textabstractThe appearance of malignant lesions in BRCA1 and BRCA2 mutation carriers (BRCA-MCs) on mammography and magnetic resonance imaging (MRI) was evaluated. Thus, 29 BRCA-MCs with breast cancer were retrospectively evaluated and the results compared with an age, tumor size and tumor type

  11. Genomic Imbalances in Rhabdomyosarcoma Cell Lines Affect Expression of Genes Frequently Altered in Primary Tumors: An Approach to Identify Candidate Genes Involved in Tumor Development

    NARCIS (Netherlands)

    Missiaglia, Edoardo; Selfe, Joanna; Hamdi, Mohamed; Williamson, Daniel; Schaaf, Gerben; Fang, Cheng; Koster, Jan; Summersgill, Brenda; Messahel, Boo; Versteeg, Rogier; Pritchard-Jones, Kathy; Kool, Marcel; Shipley, Janet

    2009-01-01

    Rhabdomyosarcomas (RMS) are the most common pediatric soft tissue sarcomas. They resemble developing skeletal muscle and are histologically divided into two main subtypes; alveolar and embryonal RMS. Characteristic genomic aberrations, including the PAX3- and PAX7-FOXO1 fusion genes in alveolar

  12. Glucose Metabolism Gene Expression Patterns and Tumor Uptake of {sup 18}F-Fluorodeoxyglucose After Radiation Treatment

    Energy Technology Data Exchange (ETDEWEB)

    Wilson, George D., E-mail: george.wilson@beaumont.edu [Department of Radiation Oncology, William Beaumont Hospital, Royal Oak, Michigan (United States); Beaumont BioBank, William Beaumont Hospital, Royal Oak, Michigan (United States); Thibodeau, Bryan J.; Fortier, Laura E.; Pruetz, Barbara L. [Beaumont BioBank, William Beaumont Hospital, Royal Oak, Michigan (United States); Galoforo, Sandra; Baschnagel, Andrew M.; Chunta, John [Department of Radiation Oncology, William Beaumont Hospital, Royal Oak, Michigan (United States); Oliver Wong, Ching Yee [Department of Diagnostic Radiology and Molecular Imaging Medicine, William Beaumont Hospital, Royal Oak, Michigan (United States); Yan, Di; Marples, Brian [Department of Radiation Oncology, William Beaumont Hospital, Royal Oak, Michigan (United States); Huang, Jiayi [Department of Radiation Oncology, William Beaumont Hospital, Royal Oak, Michigan (United States); Department of Radiation Oncology, Washington University School of Medicine, St. Louis, Missouri (United States)

    2014-11-01

    Purpose: To investigate whether radiation treatment influences the expression of glucose metabolism genes and compromises the potential use of {sup 18}F-fluorodeoxyglucose positron emission tomography (FDG-PET) as a tool to monitor the early response of head and neck cancer xenografts to radiation therapy (RT). Methods and Materials: Low passage head and neck squamous cancer cells (UT14) were injected to the flanks of female nu/nu mice to generate xenografts. After tumors reached a size of 500 mm{sup 3} they were treated with either sham RT or 15 Gy in 1 fraction. At different time points, days 3, 9, and 16 for controls and days 4, 7, 12, 21, 30, and 40 after irradiation, 2 to 3 mice were assessed with dynamic FDG-PET acquisition over 2 hours. Immediately after the FDG-PET the tumors were harvested for global gene expression analysis and immunohistochemical evaluation of GLUT1 and HK2. Different analytic parameters were used to process the dynamic PET data. Results: Radiation had no effect on key genes involved in FDG uptake and metabolism but did alter other genes in the HIF1α and glucose transport–related pathways. In contrast to the lack of effect on gene expression, changes in the protein expression patterns of the key genes GLUT1/SLC2A1 and HK2 were observed after radiation treatment. The changes in GLUT1 protein expression showed some correlation with dynamic FDG-PET parameters, such as the kinetic index. Conclusion: {sup 18}F-fluorodeoxyglucose positron emission tomography changes after RT would seem to represent an altered metabolic state and not a direct effect on the key genes regulating FDG uptake and metabolism.

  13. Pigment epithelial-derived factor gene loaded novel COOH-PEG-PLGA-COOH nanoparticles promoted tumor suppression by systemic administration

    Directory of Open Access Journals (Sweden)

    Yu T

    2016-02-01

    Full Text Available Ting Yu,1,* Bei Xu,1,* Lili He,2 Shan Xia,3 Yan Chen,1 Jun Zeng,1 Yongmei Liu,1 Shuangzhi Li,1 Xiaoyue Tan,4 Ke Ren,1 Shaohua Yao,1 Xiangrong Song1 1State Key Laboratory of Biotherapy and Cancer Center, West China Hospital, Sichuan University, and Collaborative Innovation Center for Biotherapy, 2College of Chemistry and Environment Protection Engineering, Southwest University for Nationalities, 3Central Laboratory, Science Education Department, Chengdu Normal University, Chengdu, Sichuan, 4Department of Pathology/Collaborative Innovation Center of Biotherapy, Medical School of Nankai University, Tianjin, People’s Republic of China *These authors contributed equally to this work Abstract: Anti-angiogenesis has been proposed as an effective therapeutic strategy for cancer treatment. Pigment epithelium-derived factor (PEDF is one of the most powerful endogenous anti-angiogenic reagents discovered to date and PEDF gene therapy has been recognized as a promising treatment option for various tumors. There is an urgent need to develop a safe and valid vector for its systemic delivery. Herein, a novel gene delivery system based on the newly synthesized copolymer COOH-PEG-PLGA-COOH (CPPC was developed in this study, which was probably capable of overcoming the disadvantages of viral vectors and cationic lipids/polymers-based nonviral carriers. PEDF gene loaded CPPC nanoparticles (D-NPs were fabricated by a modified double-emulsion water-in-oil-in-water (W/O/W solvent evaporation method. D-NPs with uniform spherical shape had relatively high drug loading (~1.6%, probably because the introduced carboxyl group in poly (D,L-lactide-co-glycolide terminal enhanced the interaction of copolymer with the PEDF gene complexes. An excellent in vitro antitumor effect was found in both C26 and A549 cells treated by D-NPs, in which PEDF levels were dramatically elevated due to the successful transfection of PEDF gene. D-NPs also showed a strong inhibitory effect on

  14. A expressão de genes reparadores do DNA nos tumores sincrônicos de câncer colorretal esporádico DNA repair gene expression in synchronic tumors of sporadic colorectal cancer

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    Igor Proscurshim

    2007-03-01

    Full Text Available RACIONAL: Um dos mecanismos genéticos presentes em aproximadamente 80% dos pacientes com síndrome hereditária não-polipóide do câncer colorretal (HNPCC são os defeitos nos genes reparadores de DNA, como o MSH2, MSH6 e MLH1, onde os tumores sincrônicos são relativamente freqüentes. Já no câncer colorretal esporádico as lesões sincrônicas são raras. OBJETIVO: Verificar se o mesmo mecanismo genético presente no HNPCC está presente no câncer colorretal esporádico que apresentam com lesões sincrônicas. MÉTODOS: Foram incluídos no estudo todos os pacientes com câncer colorretal sincrônico não HNPCC. Imunoistoquímica com anticorpos para MSH2,MSH6, e MLH1 foi realizada para cada tumor. RESULTADOS: Todos os pacientes apresentaram expressão normal de MSH2 e MLH1. O único gene com imunoexpressão alterada foi o MSH6. CONCLUSÃO: Possivelmente outro mecanismo genético seja responsável pelo surgimento de dois tumores sincrônicos no câncer colorretal esporádico.BACKGROUND: Mismatch repair genes (such as MSH2, MLH1 and MSH6 mutations are present in over 80% of hereditary non-polyposis colorectal cancer (HNPCC tumors, which frequently exhibit synchronous lesions. Sporadic colorectal cancer is rarely associated with synchronous lesions. AIM: To investigate the role of mismatch repair gene mutation in synchronous sporadic colorectal cancer. METHODS: Patients with sporadic synchronous colorectal adenocarcinomas were included in the study. Immunohistochemistry was performed using MSH2, MLH1 and MSH6 antibodies. RESULTS: All patients had two synchoronous lesions. None of them had altered MSH2 or MLH1 expression. One patient had altered MSH6 expression in both tumors. CONCLUSION: Possibly, other molecular mechanisms are involved in carcinogenesis of sporadic synchronous colorectal cancer.

  15. Transcriptomic and CRISPR/Cas9 technologies reveal FOXA2 as a tumor suppressor gene in pancreatic cancer.

    Science.gov (United States)

    Vorvis, Christina; Hatziapostolou, Maria; Mahurkar-Joshi, Swapna; Koutsioumpa, Marina; Williams, Jennifer; Donahue, Timothy R; Poultsides, George A; Eibl, Guido; Iliopoulos, Dimitrios

    2016-06-01

    Pancreatic ductal adenocarcinoma (PDAC) is an aggressive cancer with low survival rates and limited therapeutic options. Thus elucidation of signaling pathways involved in PDAC pathogenesis is essential for identifying novel potential therapeutic gene targets. Here, we used a systems approach to elucidate those pathways by integrating gene and microRNA profiling analyses together with CRISPR/Cas9 technology to identify novel transcription factors involved in PDAC pathogenesis. FOXA2 transcription factor was found to be significantly downregulated in PDAC relative to control pancreatic tissues. Functional experiments revealed that FOXA2 has a tumor suppressor function through inhibition of pancreatic cancer cell growth, migration, invasion, and colony formation. In situ hybridization analysis revealed miR-199a to be significantly upregulated in pancreatic cancer. Bioinformatics and luciferase analyses showed that miR-199a negatively but directly regulates FOXA2 expression through binding in its 3'-untranslated region (UTR). Evaluation of the functional importance of miR-199a on pancreatic cancer revealed that miR-199a acts as an inhibitor of FOXA2 expression, inducing an increase in pancreatic cancer cell proliferation, migration, and invasion. Additionally, gene ontology and network analyses in PANC-1 cells treated with a small interfering RNA (siRNA) against FOXA2 revealed an enrichment for cell invasion mechanisms through PLAUR and ERK activation. FOXA2 deletion (FOXA2Δ) by using two CRISPR/Cas9 vectors in PANC-1 cells induced tumor growth in vivo resulting in upregulation of PLAUR and ERK pathways in FOXA2Δ xenograft tumors. We have identified FOXA2 as a novel tumor suppressor in pancreatic cancer and it is regulated directly by miR-199a, thereby enhancing our understanding of how microRNAs interplay with the transcription factors to affect pancreatic oncogenesis. Copyright © 2016 the American Physiological Society.

  16. Clinical Utility of promoter methylation of the tumor suppressor genes DKK3, and RASSF1A in breast cancer patients

    Directory of Open Access Journals (Sweden)

    Marwa H. Saied

    2018-04-01

    Full Text Available Background: DNA methylation is the commonest known epigenetic change that results in silencing of tumor suppressor genes. Promoter methylation of tumor suppressor genes has the potential for early detection of breast cancer. Aim: Aim is to examine the potential usefulness of blood based methylation specific polymerase chain reaction (MSP of methylated DKK3 and RASSF1A genes in early detection of breast cancer. Method: Methylation status of DKK3 and RASSF1 was investigated in forty breast cancer patients, twenty fibroadenoma patients and twenty healthy ladies as control group using MSP. Results: Methylation of DKK3 promoter was found in 22.5% of breast cancer patients, while DKK3 methylation was absent in both fibroadenoma patients and control group. Similarly, methylation of RASSF1 promoter was found in 17.5% of breast cancer patients and in none of fibroadenoma and control group. Conclusion: Promoter methylation of DKK3 and RASSF1 was found in breast cancer patients while absent in control group suggesting that tumorspecific methylation of the two genes (DKK3 and RASSF1A might be a valuable biomarker for the early detection of breast cancer. Keywords: DNA methylation, Breast cancer, DKK3, RASSF1

  17. Pst I restriction fragment length polymorphism of the human placental alkaline phosphatase gene in normal placentae and tumors

    International Nuclear Information System (INIS)

    Tsavaler, L.; Penhallow, R.C.; Kam, W.; Sussman, H.H.

    1987-01-01

    The structure of the human placental alkaline phosphatase gene from normal term placentae was studied by restriction enzyme digestion and Southern blot analysis using a cDNA probe to the gene for the placental enzyme. The DNA digests fall into three distinct patterns based on the presence and intensity of an extra 1.1-kilobase Pst I Band. The extra 1.1-kilobase band is present in 9 of 27 placenta samples, and in 1 of these samples the extra band is present at double intensity. No polymorphism was revealed by digestion with restriction enzymes EcoRI, Sma I, BamHI, or Sac I. The extra Pst I-digestion site may lie in a noncoding region of the gene because no correlation was observed between the restriction fragment length polymorphism and the common placental alkaline phosphatase alleles identified by starch gel electrophoresis. In addition, because placental alkaline phosphatase is frequently re-expressed in neoplasms, the authors examined tissue from ovarian, testicular, and endometrial tumors and from BeWo choriocarcinoma cells in culture. The Pst I-DNA digestion patterns from these cells and tissues were identical to those seen in the normal ovary and term placentae. The consistent reproducible digestion patterns seen in DNA from normal and tumor tissue indicate that a major gene rearrangement is not the basis for the ectopic expression of placental alkaline phosphatase in neoplasia

  18. Deletion and down-regulation of HRH4 gene in gastric carcinomas: a potential correlation with tumor progression.

    Directory of Open Access Journals (Sweden)

    Chao Zhang

    Full Text Available BACKGROUND: Histamine is an established growth factor for gastrointestinal malignancies. The effect of histamine is largely determined locally by the histamine receptor expression pattern. Histamine receptor H4 (HRH4, the newest member of the histamine receptor family, is positively expressed on the epithelium of the gastrointestinal tract, and its function remains to be elucidated. Previously, we reported the decreased expression of HRH4 in colorectal cancers and revealed its correlation with tumor proliferation. In the current study, we aimed to investigate the abnormalities of HRH4 gene in gastric carcinomas (GCs. METHODOLOGY/PRINCIPAL FINDINGS: We analyzed H4R expression in collected GC samples by quantitative PCR, Western blot analysis, and immunostaining. Our results showed that the protein and mRNA levels of HRH4 were reduced in some GC samples, especially in advanced GC samples. Copy number decrease of HRH4 gene was observed (17.6%, 23 out of 131, which was closely correlated with the attenuated expression of H4R. In vitro studies, using gastric cancer cell lines, showed that the alteration of HRH4 expression on gastric cancer cells influences tumor growth upon exposure to histamine. CONCLUSIONS/SIGNIFICANCE: We show for the first time that deletion of HRH4 gene is present in GC cases and is closely correlated with attenuated gene expression. Down-regulation of HRH4 in gastric carcinomas plays a role in histamine-mediated growth control of GC cells.

  19. Regulation of the insulin-like developmental pathway of Caenorhabditis elegans by a homolog of the PTEN tumor suppressor gene.

    Science.gov (United States)

    Gil, E B; Malone Link, E; Liu, L X; Johnson, C D; Lees, J A

    1999-03-16

    The human PTEN tumor suppressor gene is mutated in a wide variety of sporadic tumors. To determine the function of PTEN in vivo we have studied a PTEN homolog in Caenorhabditis elegans. We have generated a strong loss-of-function allele of the PTEN homolog and shown that the deficient strain is unable to enter dauer diapause. An insulin-like phosphatidylinositol 3-OH kinase (PI3'K) signaling pathway regulates dauer-stage entry. Mutations in either the daf-2 insulin receptor-like (IRL) gene or the age-1 encoded PI3'K catalytic subunit homolog cause constitutive dauer formation and also affect the life span, brood size, and metabolism of nondauer animals. Strikingly, loss-of-function mutations in the age-1 PI3'K and daf-2 IRL genes are suppressed by loss-of-function mutations in the PTEN homolog. We establish that the PTEN homolog is encoded by daf-18, a previously uncloned gene that has been shown to interact genetically with the DAF-2 IRL AGE-1 PI3'K signaling pathway. This interaction provides clear genetic evidence that PTEN acts to antagonize PI3'K function in vivo. Given the conservation of the PI3'K signaling pathway between C. elegans and mammals, the analysis of daf-18 PTEN mutant nematodes should shed light on the role of human PTEN in the etiology of metabolic disease, aging, and cancer.

  20. Adoptive Immunotherapy for Hematological Malignancies Using T Cells Gene-Modified to Express Tumor Antigen-Specific Receptors

    Directory of Open Access Journals (Sweden)

    Hiroshi Fujiwara

    2014-12-01

    Full Text Available Accumulating clinical evidence suggests that adoptive T-cell immunotherapy could be a promising option for control of cancer; evident examples include the graft-vs-leukemia effect mediated by donor lymphocyte infusion (DLI and therapeutic infusion of ex vivo-expanded tumor-infiltrating lymphocytes (TIL for melanoma. Currently, along with advances in synthetic immunology, gene-modified T cells retargeted to defined tumor antigens have been introduced as “cellular drugs”. As the functional properties of the adoptive immune response mediated by T lymphocytes are decisively regulated by their T-cell receptors (TCRs, transfer of genes encoding target antigen-specific receptors should enable polyclonal T cells to be uniformly redirected toward cancer cells. Clinically, anticancer adoptive immunotherapy using genetically engineered T cells has an impressive track record. Notable examples include the dramatic benefit of chimeric antigen receptor (CAR gene-modified T cells redirected towards CD19 in patients with B-cell malignancy, and the encouraging results obtained with TCR gene-modified T cells redirected towards NY-ESO-1, a cancer-testis antigen, in patients with advanced melanoma and synovial cell sarcoma. This article overviews the current status of this treatment option, and discusses challenging issues that still restrain the full effectiveness of this strategy, especially in the context of hematological malignancy.

  1. Gene expression disorders of innate antibacterial signaling pathway in pancreatic cancer patients: implications for leukocyte dysfunction and tumor progression

    Science.gov (United States)

    Dąbrowska, Aleksandra; Lech, Gustaw; Słodkowski, Maciej; Słotwińska, Sylwia M.

    2014-01-01

    The study was carried out to investigate changes in gene expression of innate antibacterial signaling pathways in patients with pancreatic cancer. Expression of the following genes was measured in peripheral blood leukocytes of 55 patients with pancreatic adenocarcinoma using real-time polymerase chain reaction (RT-PCR): TLR4, NOD1, MyD88, TRAF6 and HMGB1. The levels of expression of TLR4, NOD1 and TRAF6 genes were significantly elevated (p = 0.007; p = 0.001 and p = 0.01, respectively), while MyD88 expression was markedly reduced (p = 0.0002), as compared to controls. Expression of TLR4 and NOD1 exceeded the normal level more than 3.5-fold and there was a significant correlation found between the expression of these genes (r = 0.558, p < 0.001). TLR4, NOD1 and MyD88 genes were expressed at a similar level both before and after surgery. No significant changes in the expression of HMGB1 gene were observed. The results of the study clearly indicate abnormal expression of genes belonging to innate antibacterial signaling pathways in peripheral blood leukocytes of patients with pancreatic cancer, which may lead to leukocyte dysfunction. Overexpression of TLR4, NOD1 and TRAF6 genes, and decreased MyD88 gene expression may contribute to chronic inflammation and tumor progression by up-regulation of the innate antibacterial response. The parameters tested are useful for monitoring innate immunity gene disorders and pancreatic cancer progression. PMID:26155170

  2. The anti-tumor drug bleomycin preferentially cleaves at the transcription start sites of actively transcribed genes in human cells.

    Science.gov (United States)

    Murray, Vincent; Chen, Jon K; Galea, Anne M

    2014-04-01

    The genome-wide pattern of DNA cleavage at transcription start sites (TSSs) for the anti-tumor drug bleomycin was examined in human HeLa cells using next-generation DNA sequencing. It was found that actively transcribed genes were preferentially cleaved compared with non-transcribed genes. The 143,600 identified human TSSs were split into non-transcribed genes (82,596) and transcribed genes (61,004) for HeLa cells. These transcribed genes were further split into quintiles of 12,201 genes comprising the top 20, 20-40, 40-60, 60-80, and 80-100 % of expressed genes. The bleomycin cleavage pattern at highly transcribed gene TSSs was greatly enhanced compared with purified DNA and non-transcribed gene TSSs. The top 20 and 20-40 % quintiles had a very similar enhanced cleavage pattern, the 40-60 % quintile was intermediate, while the 60-80 and 80-100 % quintiles were close to the non-transcribed and purified DNA profiles. The pattern of bleomycin enhanced cleavage had peaks that were approximately 200 bp apart, and this indicated that bleomycin was identifying the presence of phased nucleosomes at TSSs. Hence bleomycin can be utilized to detect chromatin structures that are present at actively transcribed genes. In this study, for the first time, the pattern of DNA damage by a clinically utilized cancer chemotherapeutic agent was performed on a human genome-wide scale at the nucleotide level.

  3. Tumor promoting effect of phenolphthalein on development of lung tumors induced by N-ethyl-N-nitrosourea in transgenic mice carrying human prototype c-Ha-ras gene.

    Science.gov (United States)

    Imaoka, Masako; Kashida, Yoko; Watanabe, Takao; Ueda, Makoto; Onodera, Hiroshi; Hirose, Masao; Mitsumori, Kunitoshi

    2002-06-01

    In order to examine tumor modifying effects of phenolphthalein (PhP), female transgenic mice carrying human prototype c-Ha-ras gene (rasH2 mice) were given a single intraperitoneal injection of 60 mg/kg body weight of N-ethyl-N-nitrosourea (ENU), followed by the diet containing 12,000 ppm PhP for 26-week. Histopathologically, alveolar hyperplasias, adenomas and adenocarcinomas were observed in the ENU + PhP group, but only hyperplasias and adenomas were observed in the ENU alone group. The incidence and multiplicity of adenocarcinomas in the ENU + PhP group was significantly increased as compared to that in the ENU alone group. The combined multiplicity of adenomas and adenocarcinomas in this group was also significantly higher than that of the ENU alone group. In addition, the ratio of area of adenomas in the ENU + PhP group was significantly higher than that in the ENU alone group. The result of our study suggests that PhP has a clear tumor promoting effect in the lung of rasH2 mice.

  4. Efficiency of high- and low-voltage pulse combinations for gene electrotransfer in muscle, liver, tumor, and skin

    DEFF Research Database (Denmark)

    André, F M; Gehl, J; Sersa, G

    2008-01-01

    Gene electrotransfer is gaining momentum as an efficient methodology for nonviral gene transfer. In skeletal muscle, data suggest that electric pulses play two roles: structurally permeabilizing the muscle fibers and electrophoretically supporting the migration of DNA toward or across......, but not to liver; and (4) efficient gene electrotransfer was achieved with HV field strengths below the detectability thresholds for permeabilization; and (5) the lag time interval between the HV and LV pulses decreased sensitivity to the HV pulses, enabling a wider HV amplitude range. In conclusion, HV plus LV...... the permeabilized membrane. To investigate this further, combinations of permeabilizing short high-voltage pulses (HV; hundreds of V/cm) and mainly electrophoretic long low-voltage pulses (LV; tens of V/cm) were investigated in muscle, liver, tumor, and skin in rodent models. The following observations were made...

  5. The Cloning of the Human Tumor Supressor Gene INGI: DNA Cloning into Plasmid Vector and DNA Analysis by Restriction Enzymes

    Directory of Open Access Journals (Sweden)

    Elza Ibrahim Auerkari

    2015-11-01

    Full Text Available DNA cloning is one of the most important techniques In the field of molecular biology, with a critical role in analyzing the structure and function of genes and their adjacent regulatory regions. DNA cloning is helpful in learning fundamental molecular biological techniques, since DNA cloning involves a series of them, such as polymerase chain reaction (PCR, DNA ligation, bacterial transformation, bacterial culture, plasmid DNA extraction, DNA digestion with restriction enzymes and agarose gel electrophoresis. In this paper the cloning of the human tumor suppressor gene INGI has been used to illustrate the methodology. The gene was amplified by PCR, cloned into a TA-cloning vectore, and restriction enzyme mapping was used to distinguish the sense INGI construct from the antisense INGI construct.

  6. Rare germline alterations in cancer-related genes associated with the risk of multiple primary tumor development

    DEFF Research Database (Denmark)

    Villacis, Rolando A. R.; Basso, Tatiane R; Canto, Luisa M

    2017-01-01

    Multiple primary tumors (MPT) have been described in carriers of inherited cancer predisposition genes. However, the genetic etiology of a large proportion of MPT cases remains unclear. We reviewed 267 patients with hereditary cancer predisposition syndromes (HCPS) that underwent genetic counseling...... and selected 22 patients with MPT to perform genomic analysis (CytoScan HD Array, Affymetrix) aiming to identify new alterations related to a high risk of developing MPT. Twenty patients had a positive family history of cancer and 11 met phenotypic criteria for HCPS. Genetic testing for each of the genes...... and proliferation. Overall, we identified 14 cases with rare CNVs and/or cnLOH that may contribute to the risk of MPT development. KEY MESSAGE: CNVs may explain the risk of hereditary cancer syndromes in MPT patients. CNVs affecting genes related to cancer are candidates to be involved in MPT risk. EPCAM/MSH2...

  7. Direct visualization of electroporation-assisted in vivo gene delivery to tumors using intravital microscopy – spatial and time dependent distribution

    Directory of Open Access Journals (Sweden)

    Dachs Gabi U

    2004-11-01

    Full Text Available Abstract Background Electroporation is currently receiving much attention as a way to increase drug and DNA delivery. Recent studies demonstrated the feasibility of electrogene therapy using a range of therapeutic genes for the treatment of experimental tumors. However, the transfection efficiency of electroporation-assisted DNA delivery is still low compared to viral methods and there is a clear need to optimize this approach. In order to optimize treatment, knowledge about spatial and time dependency of gene expression following delivery is of utmost importance in order to improve gene delivery. Intravital microscopy of tumors growing in dorsal skin fold window chambers is a useful method for monitoring gene transfection, since it allows non-invasive dynamic monitoring of gene expression in tumors in a live animal. Methods Intravital microscopy was used to monitor real time spatial distribution of the green fluorescent protein (GFP and time dependence of transfection efficiency in syngeneic P22 rat tumor model. DNA alone, liposome-DNA complexes and electroporation-assisted DNA delivery using two different sets of electric pulse parameters were compared. Results Electroporation-assisted DNA delivery using 8 pulses, 600 V/cm, 5 ms, 1 Hz was superior to other methods and resulted in 22% increase in fluorescence intensity in the tumors up to 6 days post-transfection, compared to the non-transfected area in granulation tissue. Functional GFP was detected within 5 h after transfection. Cells expressing GFP were detected throughout the tumor, but not in the surrounding tissue that was not exposed to electric pulses. Conclusions Intravital microscopy was demonstrated to be a suitable method for monitoring time and spatial distribution of gene expression in experimental tumors and provided evidence that electroporation-assisted gene delivery using 8 pulses, 600 V/cm, 5 ms, 1 Hz is an effective method, resulting in early onset and homogenous

  8. Direct visualization of electroporation-assisted in vivo gene delivery to tumors using intravital microscopy – spatial and time dependent distribution

    International Nuclear Information System (INIS)

    Cemazar, Maja; Wilson, Ian; Dachs, Gabi U; Tozer, Gillian M; Sersa, Gregor

    2004-01-01

    Electroporation is currently receiving much attention as a way to increase drug and DNA delivery. Recent studies demonstrated the feasibility of electrogene therapy using a range of therapeutic genes for the treatment of experimental tumors. However, the transfection efficiency of electroporation-assisted DNA delivery is still low compared to viral methods and there is a clear need to optimize this approach. In order to optimize treatment, knowledge about spatial and time dependency of gene expression following delivery is of utmost importance in order to improve gene delivery. Intravital microscopy of tumors growing in dorsal skin fold window chambers is a useful method for monitoring gene transfection, since it allows non-invasive dynamic monitoring of gene expression in tumors in a live animal. Intravital microscopy was used to monitor real time spatial distribution of the green fluorescent protein (GFP) and time dependence of transfection efficiency in syngeneic P22 rat tumor model. DNA alone, liposome-DNA complexes and electroporation-assisted DNA delivery using two different sets of electric pulse parameters were compared. Electroporation-assisted DNA delivery using 8 pulses, 600 V/cm, 5 ms, 1 Hz was superior to other methods and resulted in 22% increase in fluorescence intensity in the tumors up to 6 days post-transfection, compared to the non-transfected area in granulation tissue. Functional GFP was detected within 5 h after transfection. Cells expressing GFP were detected throughout the tumor, but not in the surrounding tissue that was not exposed to electric pulses. Intravital microscopy was demonstrated to be a suitable method for monitoring time and spatial distribution of gene expression in experimental tumors and provided evidence that electroporation-assisted gene delivery using 8 pulses, 600 V/cm, 5 ms, 1 Hz is an effective method, resulting in early onset and homogenous distribution of gene expression in the syngeneic P22 rat tumor model

  9. Heterozygous mutations in the tumor suppressor gene PATCHED provoke basal cell carcinoma-like features in human organotypic skin cultures.

    Science.gov (United States)

    Brellier, F; Bergoglio, V; Valin, A; Barnay, S; Chevallier-Lagente, O; Vielh, P; Spatz, A; Gorry, P; Avril, M-F; Magnaldo, T

    2008-11-20

    Basal cell carcinoma of the skin is the most common type of cancer in humans. The majority of these tumors displays aberrant activation of the SONIC HEDGEHOG (SHH)/PATCHED pathway, triggered by mutations in the PATCHED tumor suppressor gene, which encodes a transmembrane receptor of SHH. In this study, we took advantage of the natural genotype (PATCHED(+/-)) of healthy keratinocytes expanded from patients with the nevoid basal cell carcinoma or Gorlin syndrome to mimic heterozygous somatic mutations thought to occur in the PATCHED gene early upon basal cell carcinoma development in the general population. PATCHED(+/-) epidermis developed on a dermal equivalent containing wild-type (WT) PATCHED(+/+) fibroblasts exhibited striking invasiveness and hyperproliferation, as well as marked differentiation impairment. Deciphering the phenotype of PATCHED(+/-) keratinocytes revealed slight increases of the transcriptional activators GLI1 and GLI2-the latter known to provoke basal cell carcinoma-like tumors when overexpressed in transgenic mice. PATCHED(+/-) keratinocytes also showed a substantial increase of the cell cycle regulator cyclin D1. These data show for the first time the physiological impact of constitutive heterozygous PATCHED mutations in primary human keratinocytes and strongly argue for a yet elusive mechanism of haploinsufficiency leading to cancer proneness.

  10. Meta-Analysis of DNA Tumor-Viral Integration Site Selection Indicates a Role for Repeats, Gene Expression and Epigenetics

    Directory of Open Access Journals (Sweden)

    Janet M. Doolittle-Hall

    2015-11-01

    Full Text Available Oncoviruses cause tremendous global cancer burden. For several DNA tumor viruses, human genome integration is consistently associated with cancer development. However, genomic features associated with tumor viral integration are poorly understood. We sought to define genomic determinants for 1897 loci prone to hosting human papillomavirus (HPV, hepatitis B virus (HBV or Merkel cell polyomavirus (MCPyV. These were compared to HIV, whose enzyme-mediated integration is well understood. A comprehensive catalog of integration sites was constructed from the literature and experimentally-determined HPV integration sites. Features were scored in eight categories (genes, expression, open chromatin, histone modifications, methylation, protein binding, chromatin segmentation and repeats and compared to random loci. Random forest models determined loci classification and feature selection. HPV and HBV integrants were not fragile site associated. MCPyV preferred integration near sensory perception genes. Unique signatures of integration-associated predictive genomic features were detected. Importantly, repeats, actively-transcribed regions and histone modifications were common tumor viral integration signatures.

  11. A Genetic Screen for Genes Involved in BRCA 1 Tumor Suppressor Function

    National Research Council Canada - National Science Library

    Verma, Inder; Zhu, Quan

    2007-01-01

    Based on our initial screening, we have identified a number of candidates that are involved in DNA damage repair pathway mediated by BRCA1, which is an important aspect of tumor suppression of the molecular...

  12. Ampullary Cancers Harbor ELF3 Tumor Suppressor Gene Mutations and Exhibit Frequent WNT Dysregulation

    Directory of Open Access Journals (Sweden)

    Marie-Claude Gingras

    2016-02-01

    Full Text Available The ampulla of Vater is a complex cellular environment from which adenocarcinomas arise to form a group of histopathologically heterogenous tumors. To evaluate the molecular features of these tumors, 98 ampullary adenocarcinomas were evaluated and compared to 44 distal bile duct and 18 duodenal adenocarcinomas. Genomic analyses revealed mutations in the WNT signaling pathway among half of the patients and in all three adenocarcinomas irrespective of their origin and histological morphology. These tumors were characterized by a high frequency of inactivating mutations of ELF3, a high rate of microsatellite instability, and common focal deletions and amplifications, suggesting common attributes in the molecular pathogenesis are at play in these tumors. The high frequency of WNT pathway activating mutation, coupled with small-molecule inhibitors of β-catenin in clinical trials, suggests future treatment decisions for these patients may be guided by genomic analysis.

  13. Gene expression data from 4T1 irradiated tumors treated with TGFbeta blockade

    Data.gov (United States)

    National Aeronautics and Space Administration — Accumulating data support the concept that ionizing radiation therapy (RT) has the potential to convert the tumor into an in situ individualized vaccine; however...

  14. 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...... 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......, the impact of DDC-induced chronic liver inflammation was compared between two liver tumor models using a combination of AKT-CAT or AKT-NRAS(G12V) . Treatment with DDC and CCl4 significantly facilitated the adenoma-to-carcinoma conversion and accelerated the growth of AKT-CAT tumors. Furthermore, DDC...

  15. 99: A Novel Myc-Interacting Protein with Features of a Breast Tumor Suppressor Gene Product

    National Research Council Canada - National Science Library

    Prendergast, George

    1997-01-01

    Bin1 is a novel tumor suppressor-like molecule we identified through its ability to interact with and inhibit the oncogenic activity of the Myc oncoprotein, which is widely deregulated in breast cancer...

  16. Hypermethylation of the tumor suppressor gene PRDM1/Blimp-1 supports a pathogenetic role in EBV-positive Burkitt lymphoma

    International Nuclear Information System (INIS)

    Zhang, T; Ma, J; Nie, K; Yan, J; Liu, Y; Bacchi, C E; Queiroga, E M; Gualco, G; Sample, J T; Orazi, A; Knowles, D M; Tam, W

    2014-01-01

    PRDM1/Blimp-1 is a tumor suppressor gene in the activated B-cell subtype of diffuse large B-cell lymphomas. Its inactivation contributes to pathogenesis in this setting by impairing terminal B-cell differentiation induced by constitutive nuclear factor-κB activation. The role of PRDM1 in Burkitt lymphoma (BL) lymphomagenesis is not known. Here we identified hypermethylation of the promoter region and exon 1 of PRDM1 in all six Epstein–Barr virus (EBV)-positive BL cell lines and 12 of 23 (52%) primary EBV-positive BL or BL-related cases examined, but in none of the EBV-negative BL cell lines or primary tumors that we assessed, implying a tumor suppressor role for PRDM1 specifically in EBV-associated BL. A direct induction of PRDM1 hypermethylation by EBV is unlikely, as PRDM1 hypermethylation was not observed in EBV-immortalized B lymphoblastoid cell lines. Treatment of EBV-positive BL cells with 5′ azacytidine resulted in PRDM1 induction associated with PRDM1 demethylation, consistent with transcriptional silencing of PRDM1 as a result of DNA methylation. Overexpression of PRDM1 in EBV-positive BL cell lines resulted in cell cycle arrest. Our results expand the spectrum of lymphoid malignancies in which PRDM1 may have a tumor suppressor role and identify an epigenetic event that likely contributes to the pathogenesis of BL

  17. Hypermethylation of the tumor suppressor gene PRDM1/Blimp-1 supports a pathogenetic role in EBV-positive Burkitt lymphoma.

    Science.gov (United States)

    Zhang, T; Ma, J; Nie, K; Yan, J; Liu, Y; Bacchi, C E; Queiroga, E M; Gualco, G; Sample, J T; Orazi, A; Knowles, D M; Tam, W

    2014-11-07

    PRDM1/Blimp-1 is a tumor suppressor gene in the activated B-cell subtype of diffuse large B-cell lymphomas. Its inactivation contributes to pathogenesis in this setting by impairing terminal B-cell differentiation induced by constitutive nuclear factor-κB activation. The role of PRDM1 in Burkitt lymphoma (BL) lymphomagenesis is not known. Here we identified hypermethylation of the promoter region and exon 1 of PRDM1 in all six Epstein-Barr virus (EBV)-positive BL cell lines and 12 of 23 (52%) primary EBV-positive BL or BL-related cases examined, but in none of the EBV-negative BL cell lines or primary tumors that we assessed, implying a tumor suppressor role for PRDM1 specifically in EBV-associated BL. A direct induction of PRDM1 hypermethylation by EBV is unlikely, as PRDM1 hypermethylation was not observed in EBV-immortalized B lymphoblastoid cell lines. Treatment of EBV-positive BL cells with 5' azacytidine resulted in PRDM1 induction associated with PRDM1 demethylation, consistent with transcriptional silencing of PRDM1 as a result of DNA methylation. Overexpression of PRDM1 in EBV-positive BL cell lines resulted in cell cycle arrest. Our results expand the spectrum of lymphoid malignancies in which PRDM1 may have a tumor suppressor role and identify an epigenetic event that likely contributes to the pathogenesis of BL.

  18. Cryptotanshinone targets tumor-initiating cells through down-regulation of stemness genes expression

    OpenAIRE

    ZHANG, YING; CABARCAS, STEPHANIE M.; ZHENG, JI; SUN, LEI; MATHEWS, LESLEY A.; ZHANG, XIAOHU; LIN, HONGSHENG; FARRAR, WILLIAM L.

    2016-01-01

    Recent evidence indicates that tumor-initiating cells (TICs), also called cancer stem cells (CSCs), are responsible for tumor initiation and progression, therefore representing an important cell population that may be used as a target for the development of future anticancer therapies. In the present study, Cryptotanshinone (CT), a traditional Chinese herbal medicine, was demonstrated to regulate the behaviors of LNCaP prostate cells and prostate LNCaP TICs. The results demonstrate that treat...

  19. Detection of circulating breast tumor cells by differential expression of marker genes

    NARCIS (Netherlands)

    Bosma, Astrid J.; Weigelt, Britta; Lambrechts, A. Caro; Verhagen, Onno J. H. M.; Pruntel, Roelof; Hart, Augustinus A. M.; Rodenhuis, Sjoerd; van 't Veer, Laura J.

    2002-01-01

    Purpose: We undertook a systematic approach to identify breast cancer (BC) marker genes with molecular assays and evaluated these marker genes for the detection of minimal residual disease in peripheral blood mononuclear cells (PBMCs). Experimental Design: We used serial analysis of gene expression

  20. ETS transcription factors control transcription of EZH2 and epigenetic silencing of the tumor suppressor gene Nkx3.1 in prostate cancer.

    Directory of Open Access Journals (Sweden)

    Paolo Kunderfranco

    2010-05-01

    Full Text Available ETS transcription factors regulate important signaling pathways involved in cell differentiation and development in many tissues and have emerged as important players in prostate cancer. However, the biological impact of ETS factors in prostate tumorigenesis is still debated.We performed an analysis of the ETS gene family using microarray data and real-time PCR in normal and tumor tissues along with functional studies in normal and cancer cell lines to understand the impact in prostate tumorigenesis and identify key targets of these transcription factors. We found frequent dysregulation of ETS genes with oncogenic (i.e., ERG and ESE1 and tumor suppressor (i.e., ESE3 properties in prostate tumors compared to normal prostate. Tumor subgroups (i.e., ERG(high, ESE1(high, ESE3(low and NoETS tumors were identified on the basis of their ETS expression status and showed distinct transcriptional and biological features. ERG(high and ESE3(low tumors had the most robust gene signatures with both distinct and overlapping features. Integrating genomic data with functional studies in multiple cell lines, we demonstrated that ERG and ESE3 controlled in opposite direction transcription of the Polycomb Group protein EZH2, a key gene in development, differentiation, stem cell biology and tumorigenesis. We further demonstrated that the prostate-specific tumor suppressor gene Nkx3.1 was controlled by ERG and ESE3 both directly and through induction of EZH2.These findings provide new insights into the role of the ETS transcriptional network in prostate tumorigenesis and uncover previously unrecognized links between aberrant expression of ETS factors, deregulation of epigenetic effectors and silencing of tumor suppressor genes. The link between aberrant ETS activity and epigenetic gene silencing may be relevant for the clinical management of prostate cancer and design of new therapeutic strategies.

  1. Birt-Hogg-Dubé renal tumors are genetically distinct from other renal neoplasias and are associated with up-regulation of mitochondrial gene expression

    Directory of Open Access Journals (Sweden)

    Yonneau Laurent

    2010-12-01

    Full Text Available Abstract Background Germline mutations in the folliculin (FLCN gene are associated with the development of Birt-Hogg-Dubé syndrome (BHDS, a disease characterized by papular skin lesions, a high occurrence of spontaneous pneumothorax, and the development of renal neoplasias. The majority of renal tumors that arise in BHDS-affected individuals are histologically similar to sporadic chromophobe renal cell carcinoma (RCC and sporadic renal oncocytoma. However, most sporadic tumors lack FLCN mutations and the extent to which the BHDS-derived renal tumors share genetic defects associated with the sporadic tumors has not been well studied. Methods BHDS individuals were identified symptomatically and FLCN mutations were confirmed by DNA sequencing. Comparative gene expression profiling analyses were carried out on renal tumors isolated from individuals afflicted with BHDS and a panel of sporadic renal tumors of different subtypes using discriminate and clustering approaches. qRT-PCR was used to confirm selected results of the gene expression analyses. We further analyzed differentially expressed genes using gene set enrichment analysis and pathway analysis approaches. Pathway analysis results were confirmed by generation of independent pathway signatures and application to additional datasets. Results Renal tumors isolated from individuals with BHDS showed distinct gene expression and cytogenetic characteristics from sporadic renal oncocytoma and chromophobe RCC. The most prominent molecular feature of BHDS-derived kidney tumors was high expression of mitochondria-and oxidative phosphorylation (OXPHOS-associated genes. This mitochondria expression phenotype was associated with deregulation of the PGC-1α-TFAM signaling axis. Loss of FLCN expression across various tumor types is also associated with increased nuclear mitochondrial gene expression. Conclusions Our results support a genetic distinction between BHDS-associated tumors and other renal

  2. Induction of Apoptosis and expression of Apoptosis-related gene products in response to radiation in murine tumors

    International Nuclear Information System (INIS)

    Seong, J. S.

    1997-01-01

    To analyze the involvement of apoptosis regulatory genes p53, p21 waf1/cip1 , bax and bcl-2 in induction of apoptosis by radiation in murine tumors. The radiation-sensitive ovarian carcinoma OCa-I and the radiation-resistant hepatocarcinoma HCa-I were used. Tumors, 8mm in diameter, were irradiated with 25Gy and at various times after irradiation, ranging from 1 to 48 h, were analyzed histologically for apoptosis and by western blot for alterations in the expression of these genes. The p53 status of the tumors were determined by the polymerase chain reaction-single strand conformation polymorphism assay. Both tumors were positive for wild-type p53. Radiation induced apoptosis in OCa-I but not in HCa-I. Apoptosis developed rapidly, peaked at 2 h after irradiation and returned to almost the background level at 48 h. In OCa-I radiation upregulated the expression of p53, p21 waf1/cip1 , and the bcl-2/bax ratio was decreased. In HCa-I radiation increased the expression of both p53 and p21 waf1/cip1 , although the increase of the latter was small. The bcl-2/bax ratio was greatly increased. In general the observed changes occurred within a few hours after irradiation, and either preceded or coincided with development of apoptosis. The development of apoptosis required upregulation of both p53 and p21 waf1/cip1 as well as a decrease in bcl-2/bax ratio. In contrast, an increase in bcl-2/bax ratio prevented apoptosis in the presence of upregulated p53 and p21 waf1/cip1 . These findings identified the involvement of multiple oncogenes in apoptosis regulation in vivo and demonstrate the complexity that may be associated with the use of a single oncogene assessment for predicting the outcome of cancer therapy with cytotoxic agents. (author)

  3. 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.

  4. Induction of Apoptosis and expression of Apoptosis-related gene products in response to radiation in murine tumors

    Energy Technology Data Exchange (ETDEWEB)

    Seong, J. S. [Yonsei Univ., Seoul (Korea, Republic of). Coll. of Medicine; Hunter, N. R.; Milas, L. [Texas Univ., Houston, TX (United States)

    1997-09-01

    To analyze the involvement of apoptosis regulatory genes p53, p21{sup waf1/cip1}, bax and bcl-2 in induction of apoptosis by radiation in murine tumors. The radiation-sensitive ovarian carcinoma OCa-I and the radiation-resistant hepatocarcinoma HCa-I were used. Tumors, 8mm in diameter, were irradiated with 25Gy and at various times after irradiation, ranging from 1 to 48 h, were analyzed histologically for apoptosis and by western blot for alterations in the expression of these genes. The p53 status of the tumors were determined by the polymerase chain reaction-single strand conformation polymorphism assay. Both tumors were positive for wild-type p53. Radiation induced apoptosis in OCa-I but not in HCa-I. Apoptosis developed rapidly, peaked at 2 h after irradiation and returned to almost the background level at 48 h. In OCa-I radiation upregulated the expression of p53, p21{sup waf1/cip1}, and the bcl-2/bax ratio was decreased. In HCa-I radiation increased the expression of both p53 and p21{sup waf1/cip1}, although the increase of the latter was small. The bcl-2/bax ratio was greatly increased. In general the observed changes occurred within a few hours after irradiation, and either preceded or coincided with development of apoptosis. The development of apoptosis required upregulation of both p53 and p21{sup waf1/cip1} as well as a decrease in bcl-2/bax ratio. In contrast, an increase in bcl-2/bax ratio prevented apoptosis in the presence of upregulated p53 and p21{sup waf1/cip1}. These findings identified the involvement of multiple oncogenes in apoptosis regulation in vivo and demonstrate the complexity that may be associated with the use of a single oncogene assessment for predicting the outcome of cancer therapy with cytotoxic agents. (author).

  5. Analysis of the Mitogen-activated protein kinase kinase 4 (MAP2K4) tumor suppressor gene in ovarian cancer

    International Nuclear Information System (INIS)

    Davis, Sally J; Choong, David YH; Ramakrishna, Manasa; Ryland, Georgina L; Campbell, Ian G; Gorringe, Kylie L

    2011-01-01

    MAP2K4 is a putative tumor and metastasis suppressor gene frequently found to be deleted in various cancer types. We aimed to conduct a comprehensive analysis of this gene to assess its involvement in ovarian cancer. We screened for mutations in MAP2K4 using High Resolution Melt analysis of 149 primary ovarian tumors and methylation at the promoter using Methylation-Specific Single-Stranded Conformation Polymorphism analysis of 39 tumors. We also considered the clinical impact of changes in MAP2K4 using publicly available expression and copy number array data. Finally, we used siRNA to measure the effect of reducing MAP2K4 expression in cell lines. In addition to 4 previously detected homozygous deletions, we identified a homozygous 16 bp truncating deletion and a heterozygous 4 bp deletion, each in one ovarian tumor. No promoter methylation was detected. The frequency of MAP2K4 homozygous inactivation was 5.6% overall, and 9.8% in high-grade serous cases. Hemizygous deletion of MAP2K4 was observed in 38% of samples. There were significant correlations of copy number and expression in three microarray data sets. There was a significant correlation between MAP2K4 expression and overall survival in one expression array data set, but this was not confirmed in an independent set. Treatment of JAM and HOSE6.3 cell lines with MAP2K4 siRNA showed some reduction in proliferation. MAP2K4 is targeted by genetic inactivation in ovarian cancer and restricted to high grade serous and endometrioid carcinomas in our cohort

  6. Phytochemical Compositions of Immature Wheat Bran, and Its Antioxidant Capacity, Cell Growth Inhibition, and Apoptosis Induction through Tumor Suppressor Gene

    Directory of Open Access Journals (Sweden)

    Mi Jeong Kim

    2016-09-01

    Full Text Available The purpose of this study was to investigate the phytochemical compositions and antioxidant capacity, cell growth inhibition, and apoptosis induction in extracts of immature wheat bran. Immature wheat bran (IWB was obtained from immature wheat harvested 10 days earlier than mature wheat. The phytochemical compositions of bran extract samples were analyzed by ultra-high performance liquid chromatography. The total ferulic acid (3.09 mg/g and p-coumaric acid (75 µg/g in IWB were significantly higher than in mature wheat bran (MWB, ferulic acid: 1.79 mg/g; p-coumaric acid: 55 µg/g. The oxygen radical absorbance capacity (ORAC: 327 µM Trolox equivalents (TE/g and cellular antioxidant activity (CAA: 4.59 µM Quercetin equivalents (QE/g of the IWB were higher than those of the MWB (ORAC: 281 µM TE/g; CAA: 0.63 µM QE/g. When assessing cell proliferation, the IWB extracts resulted in the lowest EC50 values against HT-29 (18.9 mg/mL, Caco-2 (7.74 mg/mL, and HeLa cells (8.17 mg/mL among bran extract samples. Additionally, the IWB extracts increased the gene expression of p53 and PTEN (tumor suppressor genes in HT-29 cells, indicating inhibited cell growth and induced apoptosis through tumor suppressor genes.

  7. siRNA-mediated Erc gene silencing suppresses tumor growth in Tsc2 mutant renal carcinoma model.

    Science.gov (United States)

    Imamura, Osamu; Okada, Hiroaki; Takashima, Yuuki; Zhang, Danqing; Kobayashi, Toshiyuki; Hino, Okio

    2008-09-18

    Silencing of gene expression by small interfering RNAs (siRNAs) is rapidly becoming a powerful tool for genetic analysis and represents a potential strategy for therapeutic product development. However, there are no reports of systemic delivery of siRNAs for stable treatment except short hairpin RNAs (shRNAs). On the other hand, there are many reports of systemic delivery of siRNAs for transient treatment using liposome carriers and others. With regard to shRNAs, a report showed fatality in mice due to oversaturation of cellular microRNA/short hairpin RNA pathways. Therefore, we decided to use original siRNA microspheres instead of shRNA for stable treatment of disease. In this study, we designed rat-specific siRNA sequences for Erc/mesothelin, which is a tumor-specific gene expressed in the Eker (Tsc2 mutant) rat model of hereditary renal cancer and confirmed the efficacy of gene silencing in vitro. Then, by using siRNA microspheres, we found that the suppression of Erc/mesothelin caused growth inhibition of Tsc2 mutant renal carcinoma cells in tumor implantation experiments in mice.

  8. Case report of a 3-year-old girl with pleuropulmonary blastoma and family history of a tumor predisposition syndrome with c. 2830 gene mutation in DICER1

    Directory of Open Access Journals (Sweden)

    Y. Puckett

    2015-08-01

    Full Text Available Pleuropulmonary blastoma (PPB is a childhood mesenchymal pleural-based tumor that is associated with a germline mutation in DICER1 gene in familial PPB. It occurs most commonly in children between the ages of 2 and 5. Approximately 25% of patients have familial cancer syndrome which can include different combinations of PPB, lung cysts, thyroid tumors, cystic nephroma, Wilms tumor, embryonal rhabdomyosarcoma, ovarian Sertoli-Leydig cell tumors, juvenile granulosa cell tumor, gynandroblastoma, medulloblastoma, other childhood central nervous system tumors, nasal chondral mesenchymal hamartoma, and small bowel polyps. Our case report presents a child diagnosed with PPB with maternal history of bilateral ovarian Sertoli-Leydig cell tumors and papillary carcinoma of the thyroid. Molecular analysis performed on the patient and mother showed a specific gene change (c. 2830 in the DICER1 gene. The patient underwent surgical resection of the tumor and five cycles of chemotherapy. Despite this aggressive treatment, she eventually succumbed to brain metastases and was made comfort care after suffering a massive brain hemorrhage several months after the initial diagnosis of her disease.

  9. Gene expression profiling of tumor-initiating stem cells from mouse Krebs-2 carcinoma using a novel marker of poorly differentiated cells.

    Science.gov (United States)

    Potter, Ekaterina A; Dolgova, Evgenia V; Proskurina, Anastasia S; Efremov, Yaroslav R; Minkevich, Alexandra M; Rozanov, Aleksey S; Peltek, Sergey E; Nikolin, Valeriy P; Popova, Nelly A; Seledtsov, Igor A; Molodtsov, Vladimir V; Zavyalov, Evgeniy L; Taranov, Oleg S; Baiborodin, Sergey I; Ostanin, Alexander A; Chernykh, Elena R; Kolchanov, Nikolay A; Bogachev, Sergey S

    2017-02-07

    Using the ability of poorly differentiated cells to natively internalize fragments of extracellular double-stranded DNA as a marker, we isolated a tumorigenic subpopulation present in Krebs-2 ascites that demonstrated the features of tumor-inducing cancer stem cells. Having combined TAMRA-labeled DNA probe and the power of RNA-seq technology, we identified a set of 168 genes specifically expressed in TAMRA-positive cells (tumor-initiating stem cells), these genes remaining silent in TAMRA-negative cancer cells. TAMRA+ cells displayed gene expression signatures characteristic of both stem cells and cancer cells. The observed expression differences between TAMRA+ and TAMRA- cells were validated by Real Time PCR. The results obtained corroborated the biological data that TAMRA+ murine Krebs-2 tumor cells are tumor-initiating stem cells. The approach developed can be applied to profile any poorly differentiated cell types that are capable of immanent internalization of double-stranded DNA.

  10. Protein levels and gene expressions of the epidermal growth factor receptors, HER1, HER2, HER3 and HER4 in benign and malignant ovarian tumors

    DEFF Research Database (Denmark)

    Dahl Steffensen, Karina; Waldstrøm, Marianne; Fredslund Andersen, Rikke

    2008-01-01

    , but this is not elucidated in detail in ovarian tissue. High tumor-to-normal-tissue concentration ratios would be favorable for molecular targeted anti-cancer treatment. The primary aim of the study was to analyze the potential differential protein content and gene expression of the four receptors in benign and malignant...... ovarian tumors. Tissue from 207 patients (101 malignant, 19 borderline, 64 benign ovarian tumors and 23 normal ovaries) were analyzed by quantitative ELISA for HER1-HER4 protein concentrations and by real-time PCR for HER1-HER4 gene expression. HER2 was also analyzed by immunohistochemistry. The HER2......-4 receptor protein content and the median gene expression level was significantly higher in ovarian cancer patients compared to patients with benign ovarian tumors and normal ovaries (povarian cancer compared to borderline...

  11. Grape seed proanthocyanidins reactivate silenced tumor suppressor genes in human skin cancer cells by targeting epigenetic regulators

    Energy Technology Data Exchange (ETDEWEB)

    Vaid, Mudit; Prasad, Ram; Singh, Tripti; Jones, Virginia [Department of Dermatology, University of Alabama at Birmingham, Birmingham, AL 35294 (United States); Katiyar, Santosh K., E-mail: skatiyar@uab.edu [Birmingham Veterans Affairs Medical Center, Birmingham, AL 35294 (United States); Department of Dermatology, University of Alabama at Birmingham, Birmingham, AL 35294 (United States); Comprehensive Cancer Center, University of Alabama at Birmingham, Birmingham, AL 35294 (United States)

    2012-08-15

    Grape seed proanthocyanidins (GSPs) have been shown to have anti-skin carcinogenic effects in in vitro and in vivo models. However, the precise epigenetic molecular mechanisms remain unexplored. This study was designed to investigate whether GSPs reactivate silenced tumor suppressor genes following epigenetic modifications in skin cancer cells. For this purpose, A431 and SCC13 human squamous cell carcinoma cell lines were used as in vitro models. The effects of GSPs on DNA methylation, histone modifications and tumor suppressor gene expressions were studied in these cell lines using enzyme activity assays, western blotting, dot-blot analysis and real-time polymerase chain reaction (RT-PCR). We found that treatment of A431 and SCC13 cells with GSPs decreased the levels of: (i) global DNA methylation, (ii) 5-methylcytosine, (iii) DNA methyltransferase (DNMT) activity and (iv) messenger RNA (mRNA) and protein levels of DNMT1, DNMT3a and DNMT3b in these cells. Similar effects were noted when these cancer cells were treated identically with 5-aza-2′-deoxycytidine, an inhibitor of DNA methylation. GSPs decreased histone deacetylase activity, increased levels of acetylated lysines 9 and 14 on histone H3 (H3-Lys 9 and 14) and acetylated lysines 5, 12 and 16 on histone H4, and reduced the levels of methylated H3-Lys 9. Further, GSP treatment resulted in re-expression of the mRNA and proteins of silenced tumor suppressor genes, RASSF1A, p16{sup INK4a} and Cip1/p21. Together, this study provides a new insight into the epigenetic mechanisms of GSPs and may have significant implications for epigenetic therapy in the treatment/prevention of skin cancers in humans. -- Highlights: ►Epigenetic modulations have been shown to have a role in cancer risk. ►Proanthocyanidins decrease the levels of DNA methylation and histone deacetylation. ►Proanthocyanidins inhibit histone deacetylase activity in skin cancer cells. ►Proanthocyanidins reactivate tumor suppressor genes in skin

  12. Grape seed proanthocyanidins reactivate silenced tumor suppressor genes in human skin cancer cells by targeting epigenetic regulators

    International Nuclear Information System (INIS)

    Vaid, Mudit; Prasad, Ram; Singh, Tripti; Jones, Virginia; Katiyar, Santosh K.

    2012-01-01

    Grape seed proanthocyanidins (GSPs) have been shown to have anti-skin carcinogenic effects in in vitro and in vivo models. However, the precise epigenetic molecular mechanisms remain unexplored. This study was designed to investigate whether GSPs reactivate silenced tumor suppressor genes following epigenetic modifications in skin cancer cells. For this purpose, A431 and SCC13 human squamous cell carcinoma cell lines were used as in vitro models. The effects of GSPs on DNA methylation, histone modifications and tumor suppressor gene expressions were studied in these cell lines using enzyme activity assays, western blotting, dot-blot analysis and real-time polymerase chain reaction (RT-PCR). We found that treatment of A431 and SCC13 cells with GSPs decreased the levels of: (i) global DNA methylation, (ii) 5-methylcytosine, (iii) DNA methyltransferase (DNMT) activity and (iv) messenger RNA (mRNA) and protein levels of DNMT1, DNMT3a and DNMT3b in these cells. Similar effects were noted when these cancer cells were treated identically with 5-aza-2′-deoxycytidine, an inhibitor of DNA methylation. GSPs decreased histone deacetylase activity, increased levels of acetylated lysines 9 and 14 on histone H3 (H3-Lys 9 and 14) and acetylated lysines 5, 12 and 16 on histone H4, and reduced the levels of methylated H3-Lys 9. Further, GSP treatment resulted in re-expression of the mRNA and proteins of silenced tumor suppressor genes, RASSF1A, p16 INK4a and Cip1/p21. Together, this study provides a new insight into the epigenetic mechanisms of GSPs and may have significant implications for epigenetic therapy in the treatment/prevention of skin cancers in humans. -- Highlights: ►Epigenetic modulations have been shown to have a role in cancer risk. ►Proanthocyanidins decrease the levels of DNA methylation and histone deacetylation. ►Proanthocyanidins inhibit histone deacetylase activity in skin cancer cells. ►Proanthocyanidins reactivate tumor suppressor genes in skin

  13. OmoMYC blunts promoter invasion by oncogenic MYC to inhibit gene expression characteristic of MYC-dependent tumors

    OpenAIRE

    Jung, L.A.; Gebhardt, A.; Koelmel, W.; Ade, C.P.; Walz, S.; Kuper, J.; von Eyss, B.; Letschert, S.; Redel, C.; d’Artista, L.; Biankin, A.; Zender, L.; Sauer, M.; Wolf, E.; Evan, G.

    2017-01-01

    MYC genes have both essential roles during normal development and exert oncogenic functions during tumorigenesis. Expression of a dominant-negative allele of MYC, termed OmoMYC, can induce rapid tumor regression in mouse models with little toxicity for normal tissues. How OmoMYC discriminates between physiological and oncogenic functions of MYC is unclear. We have solved the crystal structure of OmoMYC and show that it forms a stable homodimer and as such recognizes DNA in the same manner as ...

  14. Development of a predictor for human brain tumors based on gene expression values obtained from two types of microarray technologies.

    Science.gov (United States)

    Castells, Xavier; Acebes, Juan José; Boluda, Susana; Moreno-Torres, Angel; Pujol, Jesús; Julià-Sapé, Margarida; Candiota, Ana Paula; Ariño, Joaquín; Barceló, Anna; Arús, Carles

    2010-04-01

    Development of molecular diagnostics that can reliably differentiate amongst different subtypes of brain tumors is an important unmet clinical need in postgenomics medicine and clinical oncology. A simple linear formula derived from gene expression values of four genes (GFAP, PTPRZ1, GPM6B, and PRELP) measured from cDNA microarrays (n = 35) have distinguished glioblastoma and meningioma cases in a previous study. We herein extend this work further and report that the above predictor formula showed its robustness when applied to Affymetrix microarray data acquired prospectively in our laboratory (n = 80) as well as publicly available data (n = 98). Importantly, GFAP and GPM6B were both retained as being significant in the predictive model upon using the Affymetrix data obtained in our laboratory, whereas the other two predictor genes were SFRP2 and SLC6A2. These results collectively indicate the importance of the expression values of GFAP and GPM6B genes sampled from the two types of microarray technologies tested. The high prediction accuracy obtained in these instances demonstrates the robustness of the predictors across microarray platforms used. This result would require further validation with a larger population of meningioma and glioblastoma cases. At any rate, this study paves the way for further application of gene signatures to more stringent biopsy discrimination challenges.

  15. Liver tumor formation by a mutant retinoblastoma protein in the transgenic mice is caused by an upregulation of c-Myc target genes

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Bo; Hikosaka, Keisuke; Sultana, Nishat; Sharkar, Mohammad Tofael Kabir [Department of Biochemistry, Hamamatsu University School of Medicine, 1-20-1 Handa-yama, Higashi-ku, Hamamatsu 431-3192 (Japan); Noritake, Hidenao [Department of Biochemistry, Hamamatsu University School of Medicine, 1-20-1 Handa-yama, Higashi-ku, Hamamatsu 431-3192 (Japan); Department of Internal Medicine, Hamamatsu University School of Medicine, 1-20-1 Handa-yama, Higashi-ku, Hamamatsu 431-3192 (Japan); Kimura, Wataru; Wu, Yi-Xin [Department of Biochemistry, Hamamatsu University School of Medicine, 1-20-1 Handa-yama, Higashi-ku, Hamamatsu 431-3192 (Japan); Kobayashi, Yoshimasa [Department of Internal Medicine, Hamamatsu University School of Medicine, 1-20-1 Handa-yama, Higashi-ku, Hamamatsu 431-3192 (Japan); Uezato, Tadayoshi [Department of Biochemistry, Hamamatsu University School of Medicine, 1-20-1 Handa-yama, Higashi-ku, Hamamatsu 431-3192 (Japan); Miura, Naoyuki, E-mail: nmiura@hama-med.ac.jp [Department of Biochemistry, Hamamatsu University School of Medicine, 1-20-1 Handa-yama, Higashi-ku, Hamamatsu 431-3192 (Japan)

    2012-01-06

    Highlights: Black-Right-Pointing-Pointer Fifty percent of the mutant Rb transgenic mice produced liver tumors. Black-Right-Pointing-Pointer In the tumor, Foxm1, Skp2, Bmi1 and AP-1 mRNAs were up-regulated. Black-Right-Pointing-Pointer No increase in expression of the Myc-target genes was observed in the non-tumorous liver. Black-Right-Pointing-Pointer Tumor formation depends on up-regulation of the Myc-target genes. -- Abstract: The retinoblastoma (Rb) tumor suppressor encodes a nuclear phosphoprotein that regulates cellular proliferation, apoptosis and differentiation. In order to adapt itself to these biological functions, Rb is subjected to modification cycle, phosphorylation and dephosphorylation. To directly determine the effect of phosphorylation-resistant Rb on liver development and function, we generated transgenic mice expressing phosphorylation-resistant human mutant Rb (mt-Rb) under the control of the rat hepatocyte nuclear factor-1 gene promoter/enhancer. Expression of mt-Rb in the liver resulted in macroscopic neoplastic nodules (adenomas) with {approx}50% incidence within 15 months old. Interestingly, quantitative reverse transcriptase-PCR analysis showed that c-Myc was up-regulated in the liver of mt-Rb transgenic mice irrespective of having tumor tissues or no tumor. In tumor tissues, several c-Myc target genes, Foxm1, c-Jun, c-Fos, Bmi1 and Skp2, were also up-regulated dramatically. We determined whether mt-Rb activated the Myc promoter in the HTP9 cells and demonstrated that mt-Rb acted as an inhibitor of wild-type Rb-induced repression on the Myc promoter. Our results suggest that continued upregulation of c-Myc target genes promotes the liver tumor formation after about 1 year of age.

  16. Molecular signatures of lymph node status by intrinsic subtype: gene expression analysis of primary breast tumors from patients with and without metastatic lymph nodes.

    Science.gov (United States)

    Shriver, Craig D; Hueman, Matthew T; Ellsworth, Rachel E

    2014-12-31

    Identification of a gene expression signature in primary breast tumors that could classify patients by lymph node status would allow patients to avoid the morbidities of surgical disruption of the lymph nodes. Attempts to identify such a signature have, to date, been unsuccessful. Because breast tumor subtypes have unique molecular characteristics and different sites of metastasis, molecular signatures for lymph node involvement may vary by subtype. Gene expression data was generated from HG U133A 2.0 arrays for 135 node positive and 210 node negative primary breast tumors. Intrinsic subtype was assigned using the BreastPRS. Differential gene expression analysis was performed using one-way ANOVA using lymph node status as the variable with a False-discovery rate basal-like (27%), HER2-enriched (14%) luminal B (7%) and normal-like (1%). Basal-like and luminal A tumors were less likely to have metastatic lymph nodes (35% and 37%, respectively) compared to luminal B or HER2-enriched (52% and 51%, respectively). No differentially expressed genes associated with lymph node status were detected when all tumors were considered together or within each subtype. Gene expression patterns from the primary tumor are not able to stratify patients by lymph node status. Although the primary breast tumor may influence tumor cell dissemination, once metastatic cells enter the lymphatics, it is likely that characteristics of the lymph node microenvironment, such as establishment of a pre-metastatic niche and release of pro-survival factors, determine which cells are able to colonize. The inability to utilize molecular profiles from the primary tumor to determine lymph node status suggest that other avenues of investigation, such as how systemic factors including diminished immune response or genetic susceptibility contribute to metastasis, may be critical in the development of tools for non-surgical assessment of lymph node status with a corresponding reduction in downstream sequelae

  17. Liver tumor formation by a mutant retinoblastoma protein in the transgenic mice is caused by an upregulation of c-Myc target genes

    International Nuclear Information System (INIS)

    Wang, Bo; Hikosaka, Keisuke; Sultana, Nishat; Sharkar, Mohammad Tofael Kabir; Noritake, Hidenao; Kimura, Wataru; Wu, Yi-Xin; Kobayashi, Yoshimasa; Uezato, Tadayoshi; Miura, Naoyuki

    2012-01-01

    Highlights: ► Fifty percent of the mutant Rb transgenic mice produced liver tumors. ► In the tumor, Foxm1, Skp2, Bmi1 and AP-1 mRNAs were up-regulated. ► No increase in expression of the Myc-target genes was observed in the non-tumorous liver. ► Tumor formation depends on up-regulation of the Myc-target genes. -- Abstract: The retinoblastoma (Rb) tumor suppressor encodes a nuclear phosphoprotein that regulates cellular proliferation, apoptosis and differentiation. In order to adapt itself to these biological functions, Rb is subjected to modification cycle, phosphorylation and dephosphorylation. To directly determine the effect of phosphorylation-resistant Rb on liver development and function, we generated transgenic mice expressing phosphorylation-resistant human mutant Rb (mt-Rb) under the control of the rat hepatocyte nuclear factor-1 gene promoter/enhancer. Expression of mt-Rb in the liver resulted in macroscopic neoplastic nodules (adenomas) with ∼50% incidence within 15 months old. Interestingly, quantitative reverse transcriptase-PCR analysis showed that c-Myc was up-regulated in the liver of mt-Rb transgenic mice irrespective of having tumor tissues or no tumor. In tumor tissues, several c-Myc target genes, Foxm1, c-Jun, c-Fos, Bmi1 and Skp2, were also up-regulated dramatically. We determined whether mt-Rb activated the Myc promoter in the HTP9 cells and demonstrated that mt-Rb acted as an inhibitor of wild-type Rb-induced repression on the Myc promoter. Our results suggest that continued upregulation of c-Myc target genes promotes the liver tumor formation after about 1 year of age.

  18. Status and advances of p53-gene therapy and radiotherapy in malignant tumor

    International Nuclear Information System (INIS)

    Duan Xin; Chinese Academy of Sciences, Beijing; Zhang Hong

    2006-01-01

    Cancer treatment is one of the most important fields in medical research. All strategies such as radio-therapy, chemotherapy, surgery, and gene-based therapy have their own advantages and disadvantages. Nowadays, a novel method which combined p53-gene therapy with radiotherapy plays an important role in the field of cancer research. This review summarized the current state of combined therapies of p53-gene therapy and radiotherapy, possible mechanism and recent progress. (authors)

  19. Effect of recombinant adenovirus encoding human p53 tumor suppressor gene combined with radiation therapy on human lymphoma cells lines

    International Nuclear Information System (INIS)

    Yu Zeyang; Fan Wo; Li Dongqing; Zhu Ran; Wan Jianmei; Wang Yongqing; Wu Jinchang

    2008-01-01

    This paper analyzes the inhibitory effect and radiation sensitization of recombinant adenovirus encoding human p53 tumor suppressor gene (rAd-p53) on human lymphoma cell lines. Human lymphoma cell lines were treated with rAd-p53, radiation therapy and combined treatment, respectively. The cell growth inhibition was assessed by MTF. The cell cycle and apoptosis were detected by flow cytometry, and the p53 protein expression was detected by Western blotting. The results showed that extrinsic p53 gene have expressed to some degree, but not at high level. The role of inhibition and radiation sensitivity of rAd-p53 was not significant to human lymphoma cell lines. (authors)

  20. Characterization of a canine tetranucleotide microsatellite marker located in the first intron of the tumor necrosis factor alpha gene.

    Science.gov (United States)

    Watanabe, Masashi; Tanaka, Kazuaki; Takizawa, Tatsuya; Segawa, Kazuhito; Neo, Sakurako; Tsuchiya, Ryo; Murata, Michiko; Murakami, Masaru; Hisasue, Masaharu

    2014-01-01

    A polymorphic tetranucleotide (GAAT)n microsatellite in the first intron of the canine tumor necrosis factor alpha (TNFA) gene was characterized in this study; 139 dogs were analyzed: 22 Beagles, 26 Chihuahuas, 20 Miniature Dachshunds, 24 Miniature Poodles, 22 Pembroke Welsh Corgis and 25 Shiba Inus. We detected the presence of the 4 alleles (GAAT)5, (GAAT)6, (GAAT)7 and (GAAT)8, including 9 of the 10 expected genotypes. The expected heterozygosity (He) and the polymorphic information content (PIC) value of this microsatellite locus varied from 0.389 to 0.749 and from 0.333 to 0.682, respectively, among the 6 breeds. The allelic frequency differed greatly among breeds, but this microsatellite marker was highly polymorphic and could be a useful marker for the canine TNFA gene.

  1. pRRophetic: an R package for prediction of clinical chemotherapeutic response from tumor gene expression levels.

    Directory of Open Access Journals (Sweden)

    Paul Geeleher

    Full Text Available We recently described a methodology that reliably predicted chemotherapeutic response in multiple independent clinical trials. The method worked by building statistical models from gene expression and drug sensitivity data in a very large panel of cancer cell lines, then applying these models to gene expression data from primary tumor biopsies. Here, to facilitate the development and adoption of this methodology we have created an R package called pRRophetic. This also extends the previously described pipeline, allowing prediction of clinical drug response for many cancer drugs in a user-friendly R environment. We have developed several other important use cases; as an example, we have shown that prediction of bortezomib sensitivity in multiple myeloma may be improved by training models on a large set of neoplastic hematological cell lines. We have also shown that the package facilitates model development and prediction using several different classes of data.

  2. Mutations in the isocitrate dehydrogenase genes IDH1 and IDH2 in tumors

    NARCIS (Netherlands)

    Schaap, Frank G.; French, Pim J.; Bovée, Judith V. M. G.

    2013-01-01

    Heterozygous hotspot mutations in isocitrate dehydrogenases (IDH) IDH1 or IDH2 are frequently observed in specific types of cartilaginous tumors, gliomas, and leukemias. Mutant IDH enzyme loses its normal activity to convert isocitrate into α-ketoglutarate (αKG) and instead acquires the ability to

  3. Zebrafish with mutations in mismatch repair genes develop neurofibromas and other tumors.

    NARCIS (Netherlands)

    Feitsma, H.; Kuiper, R.V.; Korving, J.; Nijman, I.J.; Cuppen, E.

    2008-01-01

    Defective mismatch repair (MMR) in humans causes hereditary nonpolyposis colorectal cancer. This genetic predisposition to colon cancer is linked to heterozygous familial mutations, and loss-of-heterozygosity is necessary for tumor development. In contrast, the rare cases with biallelic MMR

  4. Microarray Gene Expression Analysis of Murine Tumor Heterogeneity Defined by Dynamic Contrast-Enhanced MRI

    Directory of Open Access Journals (Sweden)

    Nick G. Costouros

    2002-07-01

    Full Text Available Current methods of studying angiogenesis are limited in their ability to serially evaluate in vivo function throughout a target tissue. Dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI and pharmacokinetic modeling provide a useful method for evaluating tissue vasculature based on contrast accumulation and washout. While it is often assumed that areas of high contrast enhancement and washout comprise areas of increased angiogenesis and tumor activity, the actual molecular pathways that are active in such areas are poorly understood. Using DCE-MRI in a murine subcutaneous tumor model, we were able to perform pharmacokinetic functional analysis of a tumor, coregistration of MRI images with histological cross-sections, immunohistochemistry, laser capture microdissection, and genetic profiling of tumor heterogeneity based on pharmacokinetic parameters. Using imaging as a template for biologic investigation, we have not found evidence of increased expression of proangiogenic modulators at the transcriptional level in either distinct pharmacokinetic region. Furthermore, these regions show no difference on histology and CD31 immunohistochemistry. However, the expression of ribosomal proteins was greatly increased in high enhancement and washout regions, implying increased protein translation and consequent increased cellular activity. Together, these findings point to the potential importance of posttranscriptional regulation in angiogenesis and the need for the development of angiogenesis-specific contrast agents to evaluate in vivo angiogenesis at a molecular level.

  5. In vivo corrosion, tumor outcome, and microarray gene expression for two types of muscle-implanted tungsten alloys

    International Nuclear Information System (INIS)

    Schuster, B.E.; Roszell, L.E.; Murr, L.E.; Ramirez, D.A.; Demaree, J.D.; Klotz, B.R.; Rosencrance, A.B.; Dennis, W.E.; Bao, W.; Perkins, E.J.; Dillman, J.F.; Bannon, D.I.

    2012-01-01

    Tungsten alloys are composed of tungsten microparticles embedded in a solid matrix of transition metals such as nickel, cobalt, or iron. To understand the toxicology of these alloys, male F344 rats were intramuscularly implanted with pellets of tungsten/nickel/cobalt, tungsten/nickel/iron, or pure tungsten, with tantalum pellets as a negative control. Between 6 and 12 months, aggressive rhabdomyosarcomas formed around tungsten/nickel/cobalt pellets, while those of tungsten/nickel/iron or pure tungsten did not cause cancers. Electron microscopy showed a progressive corrosion of the matrix phase of tungsten/nickel/cobalt pellets over 6 months, accompanied by high urinary concentrations of nickel and cobalt. In contrast, non-carcinogenic tungsten/nickel/iron pellets were minimally corroded and urinary metals were low; these pellets having developed a surface oxide layer in vivo that may have restricted the mobilization of carcinogenic nickel. Microarray analysis of tumors revealed large changes in gene expression compared with normal muscle, with biological processes involving the cell cycle significantly up‐regulated and those involved with muscle development and differentiation significantly down‐regulated. Top KEGG pathways disrupted were adherens junction, p53 signaling, and the cell cycle. Chromosomal enrichment analysis of genes showed a highly significant impact at cytoband 7q22 (chromosome 7) which included mouse double minute (MDM2) and cyclin‐dependant kinase (CDK4) as well as other genes associated with human sarcomas. In conclusion, the tumorigenic potential of implanted tungsten alloys is related to mobilization of carcinogenic metals nickel and cobalt from corroding pellets, while gene expression changes in the consequent tumors are similar to radiation induced animal sarcomas as well as sporadic human sarcomas. -- Highlights: ► Tungsten/nickel/cobalt, tungsten/nickel/iron, and pure tungsten were studied. ► Male Fischer rats implanted with

  6. In vivo corrosion, tumor outcome, and microarray gene expression for two types of muscle-implanted tungsten alloys

    Energy Technology Data Exchange (ETDEWEB)

    Schuster, B.E. [U.S. Army Research Laboratory, Weapons and Materials Research Directorate, B434 Mulberry Road, Aberdeen Proving Ground, MD 21005-5609 (United States); Roszell, L.E. [U.S. Army Institute of Public Health, 5158 Blackhawk Road, Aberdeen Proving Ground, MD 21010‐5403 (United States); Murr, L.E.; Ramirez, D.A. [Department of Metallurgical and Materials Engineering, University of Texas, El Paso, TX 79968 (United States); Demaree, J.D. [U.S. Army Research Laboratory, Weapons and Materials Research Directorate, B434 Mulberry Road, Aberdeen Proving Ground, MD 21005-5609 (United States); Klotz, B.R. [Dynamic Science Inc., Aberdeen Proving Ground, MD 21005‐5609 (United States); Rosencrance, A.B.; Dennis, W.E. [U.S. Army Center for Environmental Health Research, Department of Chemistry, Ft. Detrick, MD 21702‐5010 (United States); Bao, W. [SAS Institute, Inc. SAS Campus Drive, Cary, NC 27513 (United States); Perkins, E.J. [U.S. Army Engineer Research and Development Center, 3909 Hall Ferry Road, Vicksburg MS 39180 (United States); Dillman, J.F. [U.S. Army Medical Research Institute of Chemical Defense, 3100 Ricketts Point Road, Aberdeen Proving Ground, MD 21010‐5400 (United States); Bannon, D.I., E-mail: desmond.bannon@us.army.mil [U.S. Army Institute of Public Health, 5158 Blackhawk Road, Aberdeen Proving Ground, MD 21010‐5403 (United States)

    2012-11-15

    Tungsten alloys are composed of tungsten microparticles embedded in a solid matrix of transition metals such as nickel, cobalt, or iron. To understand the toxicology of these alloys, male F344 rats were intramuscularly implanted with pellets of tungsten/nickel/cobalt, tungsten/nickel/iron, or pure tungsten, with tantalum pellets as a negative control. Between 6 and 12 months, aggressive rhabdomyosarcomas formed around tungsten/nickel/cobalt pellets, while those of tungsten/nickel/iron or pure tungsten did not cause cancers. Electron microscopy showed a progressive corrosion of the matrix phase of tungsten/nickel/cobalt pellets over 6 months, accompanied by high urinary concentrations of nickel and cobalt. In contrast, non-carcinogenic tungsten/nickel/iron pellets were minimally corroded and urinary metals were low; these pellets having developed a surface oxide layer in vivo that may have restricted the mobilization of carcinogenic nickel. Microarray analysis of tumors revealed large changes in gene expression compared with normal muscle, with biological processes involving the cell cycle significantly up‐regulated and those involved with muscle development and differentiation significantly down‐regulated. Top KEGG pathways disrupted were adherens junction, p53 signaling, and the cell cycle. Chromosomal enrichment analysis of genes showed a highly significant impact at cytoband 7q22 (chromosome 7) which included mouse double minute (MDM2) and cyclin‐dependant kinase (CDK4) as well as other genes associated with human sarcomas. In conclusion, the tumorigenic potential of implanted tungsten alloys is related to mobilization of carcinogenic metals nickel and cobalt from corroding pellets, while gene expression changes in the consequent tumors are similar to radiation induced animal sarcomas as well as sporadic human sarcomas. -- Highlights: ► Tungsten/nickel/cobalt, tungsten/nickel/iron, and pure tungsten were studied. ► Male Fischer rats implanted with

  7. The Acetyltransferase p300/CBP-Associated Factor Is a p53 Target Gene in Breast Tumor Cells

    Directory of Open Access Journals (Sweden)

    George S. Watts

    2004-05-01

    Full Text Available p300/CBP-associated factor (PCAF is a coactivator of the tumor suppressor, p53. PCAF participates in p53's transactivation of target genes through acetylation of both bound p53 and histones within p53 target promoters. Using microarrays, we discovered that PCAF itself is induced by p53 in a panel of breast tumor cell lines. Two p53 mutant breast tumor cell lines, BT-549 and UACC-1179, were chosen for further study of PCAF induction by wild-type p53. PCAF induction following adenoviral transduction of p53 expression was confirmed with real-time polymerase chain reaction in a time course experiment. Chromatin immunoprecipitation experiments then showed that PCAF induction was associated with increased p53 binding to the PCAF promoter, which contains p53 consensus-binding sites. PCAF induction by p53 activity was further demonstrated in wild-type p53 MCF10A cells when PCAF expression was induced following activation of endogenous wild-type p53 with doxorubicin in a dose- and time-dependent manner. Furthermore, the doxorubicin-induced increase in PCAF expression was blocked by pretreatment of the MCF10A cells with siRNA (small interfering RNA targeted against p53 mRNA. Taken together, the results show that PCAF expression can be induced by wild-type p53.

  8. Toward the gene(s) for Wiedemann-Beckwith syndrome and associated tumors in two different regions of 11p15

    Energy Technology Data Exchange (ETDEWEB)

    Henry, J.; Chehenase, V.; Boulevin, C. [INSERM, Paris (France)] [and others

    1994-09-01

    Wiedemann-Beckwith syndrome (WBS) is a malformation syndrome associated with predisposition to different types of tumors (WT, ADCC). Cytogenetic and familial studies mapped the WBS locus to 11p15.5. Genomic imprinting has been implicated in the expression of the syndrome. Using 11p15 specific markers we have determined the parental origin of both chromosomes 11 in sporadic WBS cases. Probands in 5 out of 26 informative families (25%) displayed uniparental disomy (UPD) corresponding to a paternal isodisomy for region 11p15.5. Mosaic phenotypes reflect the timing of their origin and the fate of cells involved as well as the cell-specific pattern of imprinting. Somatic mosaicism for UPD may thus explain the incomplete forms of WBS, the association of hemihypertrophy in sporadic WBS and even some cases of isolated hemihypertrophy. Moreover, the risk (60%) of developing a tumor seems higher for patients with paternal 11p UPD than for WBS patients in general (7.5%). Two different genomic libraries specific for region 11p15.5 were constructed and screened to isolate and characterize the gene(s) responsible for WBS and/or tumor progression. The characterization and and the localization of these cDNAs are in progress. 5 CA repeats genetically mapped in 11p15 were used to isolate YACs (CEPH). These CA repeats are now physically mapped using a panel of hybrids specific for the 11p15 region, and the contigs of YACs mapping in the regions of interest will be used to isolate coding sequences.

  9. Interleukin-6 and tumor necrosis factor-alpha gene polymorphisms in chronic idiopathic urticaria.

    Science.gov (United States)

    Tavakol, M; Amirzargar, A A; Movahedi, M; Aryan, Z; Bidoki, A Z; Gharagozlou, M; Aghamohammadi, A; Nabavi, M; Ahmadvand, A; Behniafard, N; Heidari, K; Soltani, S; Rezaei, N

    2014-01-01

    This study was performed to evaluate association of gene polymorphisms among proinflammatory cytokines and susceptibility to chronic idiopathic urticaria (CIU). Ninety patients with prolonged urticaria more than 6 weeks were included as case group. Single nucleotide polymorphisms (SNPs) of IL-6 (G/C -174, G/A nt565) and TNF-α (G/A -308, G/A -238) were evaluated, using polymerase chain reaction (PCR); and the results were compared to the control group. G allele was significantly higher in the patients at locus of -238 of promoter of TNF-α gene (p<0.001). Frequency of following genotypes were significantly lower in patients with CIU, compared to controls: AG at -308 and GA at -238 of TNF-α gene (p<0.05 and p<0.001, respectively), CG at -174 and GG at +565 of IL-6 gene (p<0.05). Additionally, following genotypes were more common among patients with CIU: GG at -308 and -238 of TNF-α gene (p<0.05 and p<0.001, respectively), GG at -174 and GA at +565 of IL-6 gene (p<0.05). Pro-inflammatory cytokine gene polymorphisms can affect susceptibility to CIU. TNF-α promoter polymorphisms as well as IL-6 gene polymorphisms are associated with CIU. Copyright © 2013 SEICAP. Published by Elsevier Espana. All rights reserved.

  10. Short-term arginine deprivation results in large-scale modulation of hepatic gene expression in both normal and tumor cells: microarray bioinformatic analysis

    Directory of Open Access Journals (Sweden)

    Sabo Edmond

    2006-09-01

    Full Text Available Abstract Background We have reported arginine-sensitive regulation of LAT1 amino acid transporter (SLC 7A5 in normal rodent hepatic cells with loss of arginine sensitivity and high level constitutive expression in tumor cells. We hypothesized that liver cell gene expression is highly sensitive to alterations in the amino acid microenvironment and that tumor cells may differ substantially in gene sets sensitive to amino acid availability. To assess the potential number and classes of hepatic genes sensitive to arginine availability at the RNA level and compare these between normal and tumor cells, we used an Affymetrix microarray approach, a paired in vitro model of normal rat hepatic cells and a tumorigenic derivative with triplicate independent replicates. Cells were exposed to arginine-deficient or control conditions for 18 hours in medium formulated to maintain differentiated function. Results Initial two-way analysis with a p-value of 0.05 identified 1419 genes in normal cells versus 2175 in tumor cells whose expression was altered in arginine-deficient conditions relative to controls, representing 9–14% of the rat genome. More stringent bioinformatic analysis with 9-way comparisons and a minimum of 2-fold variation narrowed this set to 56 arginine-responsive genes in normal liver cells and 162 in tumor cells. Approximately half the arginine-responsive genes in normal cells overlap with those in tumor cells. Of these, the majority was increased in expression and included multiple growth, survival, and stress-related genes. GADD45, TA1/LAT1, and caspases 11 and 12 were among this group. Previously known amino acid regulated genes were among the pool in both cell types. Available cDNA probes allowed independent validation of microarray data for multiple genes. Among genes downregulated under arginine-deficient conditions were multiple genes involved in cholesterol and fatty acid metabolism. Expression of low-density lipoprotein receptor was

  11. Retinoid-induced expression and activity of an immediate early tumor suppressor gene in vascular smooth muscle cells.

    Directory of Open Access Journals (Sweden)

    Jeffrey W Streb

    2011-04-01

    Full Text Available Retinoids are used clinically to treat a number of hyper-proliferative disorders and have been shown in experimental animals to attenuate vascular occlusive diseases, presumably through nuclear receptors bound to retinoic acid response elements (RARE located in target genes. Here, we show that natural or synthetic retinoids rapidly induce mRNA and protein expression of a specific isoform of A-Kinase Anchoring Protein 12 (AKAP12β in cultured smooth muscle cells (SMC as well as the intact vessel wall. Expression kinetics and actinomycin D studies indicate Akap12β is a retinoid-induced, immediate-early gene. Akap12β promoter analyses reveal a conserved RARE mildly induced with atRA in a region that exhibits hyper-acetylation. Immunofluorescence microscopy and protein kinase A (PKA regulatory subunit overlay assays in SMC suggest a physical association between AKAP12β and PKA following retinoid treatment. Consistent with its designation as a tumor suppressor, inducible expression of AKAP12β attenuates SMC growth in vitro. Further, immunohistochemistry studies establish marked decreases in AKAP12 expression in experimentally-injured vessels of mice as well as atheromatous lesions in humans. Collectively, these results demonstrate a novel role for retinoids in the induction of an AKAP tumor suppressor that blocks vascular SMC growth thus providing new molecular insight into how retiniods may exert their anti-proliferative effects in the injured vessel wall.

  12. [Construction of recombinant adenovirus vector expressing extracellular domain of TbetaR-II-RANTES fusion gene and its anti-tumor effects].

    Science.gov (United States)

    Wang, Xu-Dong; Liu, Hong; Cao, Shui; Li, Hui; Ren, Xiu-Bao; Hao, Xi-Shan

    2007-06-01

    To construct a recombinant adenovirus vector expressing TbetaR-II extracellular domain-RANTES fusion gene and evaluate its anti-tumor effects. Mouse origin TbetaR-II extracellular domain and RANTES gene were amplified by RT-PCR. The TbetaR-II extracellular domain-RANTES fusion gene was amplified by overlapping PCR method. TbetaR-II extracellular domain-RANTES fusion gene was cloned into pDC316 vector. The recombinant adenovirus vector expressing the fusion gene was constructed by adMax adenovirus vector creation system. Recombinant adenovirus vector expressing the fusion gene was transfected into LA795 cells. The expression of recombinant adenovirus was checked by Westen blot. The levels of TGF-beta1, RANTES in supernatant were checked by ELISA. The transfected cells were counted and growth curve was obtained. Apoptosis of transfected cells was detected by Annexin V FITC method. The chemotactic activity of supernatant of transfected cells to splenic lymphocytes was assayed. Transfected cells (1 x 10(5)) were inoculated into T739 mice and to observe the tumor growth and survival time. Ad-TbetaR-II extracellular domain, Ad-RANTES and Ad-TbetaR-II extracellular domain-RANTES fusion gene(1 x 10(10) pfu) were injected into the tumor in T739 mice. The tumor size and tumor weight were recorded and tumor growth inhibition rate was counted and statistically analyzed. TbetaR-II extracellular domain and RANTES gene were amplified by RT-PCR and TbetaR-II extracellular domain-RANTES fusion gene amplified by overlapping PCR, were identified by DNA sequence analysis. Restriction enzyme digestion analysis showed that the recombinant vector was constructed correctly. The recombinant adenovirus vector expressing the fusion gene was constructed successfully using the AdMax Adenovirus Vector Creation System. Its titer was 8 x 10(10) pfu/ml. Ad-TbetaR-II extracellular domain-RANTES fusion gene was transfected into LA795 cells and had specific protein fragment proved by Western Blot

  13. Tumor necrosis factor-α -308G/A gene polymorphism in Egyptian children with immune thrombocytopenic purpura.

    Science.gov (United States)

    El Sissy, Maha H; El Sissy, A H; Elanwary, Sherif

    2014-07-01

    Immune thrombocytopenic purpura (ITP) is an autoimmune disease characterized by increased platelet destruction. Although the cause of ITP remains unclear, it is accepted that both environmental and genetic factors play an important role in the development of the disease. Children with ITP have a T-helper 1-type cytokine pattern with elevated levels of tumor necrosis factor-alpha (TNF-α) as in most autoimmune diseases. Researchers have shown that polymorphism in the TNF-α gene at position -308 affects gene transcriptions with increased TNF-α production. The current case-control study aimed at detecting the frequency of TNF-α -308G/A gene polymorphism as genetic markers in Egyptian children with ITP, and to clear out their possible role in choosing the treatment protocols of therapy, using PCR restriction fragment length polymorphism assay. Ninety-two ITP patients and 100 age and sex-matched healthy controls were recruited in the study. The results obtained revealed that the frequency of TNF-α -308A/A homotype in ITP patients was significantly higher than that of the controls, and conferred almost six-fold increased risk of ITP acquisition. The polymorphic A allele frequency was significantly higher in ITP patients than in the controls, conferring almost two-fold increased ITP risk. In conclusion, our study suggests the possibility that TNF-α -308 gene polymorphism may contribute to the susceptibility of childhood ITP in Egyptian children.

  14. Role of arachidonic acid metabolism in transcriptional induction of tumor necrosis factor gene expression by phorbol ester

    Energy Technology Data Exchange (ETDEWEB)

    Horiguchi, J.; Spriggs, D.; Imamura, K.; Stone, R.; Luebbers, R.; Kufe, D.

    1989-01-01

    The treatment of human HL-60 promyelocytic leukemia cells with 12-0 tetradecanoylphorbol-13-acetate (TPA) is associated with induction of tumor necrosis factor (TNF) transcripts. The study reported here has examined TPA-induced signaling mechanisms responsible for the regulation of TNF gene expression in these cells. Run-on assays demonstrated that TPA increases TNS mRNA levels by transcriptional activation of this gene. The induction of TNF transcripts by TPA was inhibited by the isoquinolinesulfonamide derivative H7 but not by HA1004, suggesting that this effect of TPA is mediated by activation of protein kinase C. TPA treatment also resulted in increased arachidonic acid release. Moreover, inhibitors of phospholipase, A/sub 2/ blocked both the increase in arachidonic acid release and the induction of TNF transcripts. These findings suggest that TPA induces TNF gene expression through the formation of arachidonic acid metabolites. Although indomethacin had no detectable effect on this induction of TNF transcripts, ketoconazole, an inhibitor of 5-lipoxygenase, blocked TPA-induced increases in TNF mRNA levels. Moreover, TNF mRNA levels were increased by the 5-lipoxygenase metabolite leukotriene B/sub 4/. In contrast, the cyclooxygenase metabolite prostaglandin E/sub 2/ inhibited the induction of TNF transcripts by TPA. Taken together, these results suggest that TPA induces TNF gene expression through the arachidonic acid cascade and that the level of TNF transcripts is regulated by metabolites of the pathway, leukotriene B/sub 4/ and prostaglandin E/sub 2/.

  15. Inactivation of the FLCN tumor suppressor gene induces TFE3 transcriptional activity by increasing its nuclear localization.

    Directory of Open Access Journals (Sweden)

    Seung-Beom Hong

    2010-12-01

    Full Text Available Germline mutations in a tumor suppressor gene FLCN lead to development of fibrofolliculomas, lung cysts and renal cell carcinoma (RCC in Birt-Hogg-Dubé syndrome. TFE3 is a member of the MiTF/TFE transcription factor family and Xp11.2 translocations found in sporadic RCC involving TFE3 result in gene fusions and overexpression of chimeric fusion proteins that retain the C-terminal DNA binding domain of TFE3. We found that GPNMB expression, which is regulated by MiTF, was greatly elevated in renal cancer cells harboring either TFE3 translocations or FLCN inactivation. Since TFE3 is implicated in RCC, we hypothesized that elevated GPNMB expression was due to increased TFE3 activity resulting from the inactivation of FLCN.TFE3 knockdown reduced GPNMB expression in renal cancer cells harboring either TFE3 translocations or FLCN inactivation. Moreover, FLCN knockdown induced GPNMB expression in FLCN-restored renal cancer cells. Conversely, wildtype FLCN suppressed GPNMB expression in FLCN-null cells. FLCN inactivation was correlated with increased TFE3 transcriptional activity accompanied by its nuclear localization as revealed by elevated GPNMB mRNA and protein expression, and predominantly nuclear immunostaining of TFE3 in renal cancer cells, mouse embryo fibroblast cells, mouse kidneys and mouse and human renal tumors. Nuclear localization of TFE3 was associated with TFE3 post-translational modifications including decreased phosphorylation.Increased TFE3 activity is a downstream event induced by FLCN inactivation and is likely to be important for renal tumor development. This study provides an important novel mechanism for induction of TFE3 activity in addition to TFE3 overexpression resulting from Xp11.2 translocations, suggesting that TFE3 may be more broadly involved in tumorigenesis.

  16. Deletion of the gene encoding MyD88 protects from anorexia in a mouse tumor model.

    Science.gov (United States)

    Ruud, Johan; Bäckhed, Fredrik; Engblom, David; Blomqvist, Anders

    2010-05-01

    The anorexia-cachexia syndrome, characterized by a rise in energy expenditure and loss of body weight that paradoxically are associated with loss of appetite and decreased food intake, contributes significantly to the morbidity and mortality in cancer. While the pathophysiology of cancer anorexia-cachexia is poorly understood, evidence indicates that pro-inflammatory cytokines are key mediators of this response. Although inflammation hence is recognized as an important component of cancer anorexia-cachexia, the molecular pathways involved are largely unknown. We addressed this issue in mice carrying a deletion of the gene encoding MyD88, the key intracellular adaptor molecule in Toll-like and interleukin-1 family receptor signaling. Wild-type and MyD88-deficient mice were transplanted subcutaneously with a syngenic methylcholanthrene-induced tumor (MCG 101) and daily food intake and body weight were recorded. Wild-type mice showed progressively reduced food intake from about 5days after tumor transplantation and displayed a slight body weight loss after 10days when the experiment was terminated. In contrast, MyD88-deficient mice did not develop anorexia, and displayed a positive body weight development during the observation period. While the MyD88-deficient mice on average developed somewhat smaller tumors than wild-type mice, this did not explain the absence of anorexia, because anorexia was seen in wild-type mice with similar tumor mass as non-anorexic knock-out mice. These data suggest that MyD88-dependent mechanisms are involved in the metabolic derangement during cancer anorexia-cachexia and that innate immune signaling is important for the development of this syndrome. Copyright 2010 Elsevier Inc. All rights reserved.

  17. Cystatin D is a candidate tumor suppressor gene induced by vitamin D in human colon cancer cells.

    Science.gov (United States)

    Alvarez-Díaz, Silvia; Valle, Noelia; García, José Miguel; Peña, Cristina; Freije, José M P; Quesada, Víctor; Astudillo, Aurora; Bonilla, Félix; López-Otín, Carlos; Muñoz, Alberto

    2009-08-01

    The active vitamin D metabolite 1alpha,25-dihydroxyvitamin D3 [1alpha,25(OH)2D3] has wide but not fully understood antitumor activity. A previous transcriptomic analysis of 1alpha,25(OH)2D3 action on human colon cancer cells revealed cystatin D (CST5), which encodes an inhibitor of several cysteine proteases of the cathepsin family, as a candidate target gene. Here we report that 1alpha,25(OH)2D3 induced vitamin D receptor (VDR) binding to, and activation of, the CST5 promoter and increased CST5 RNA and protein levels in human colon cancer cells. In cells lacking endogenous cystatin D, ectopic cystatin D expression inhibited both proliferation in vitro and xenograft tumor growth in vivo. Furthermore, cystatin D inhibited migration and anchorage-independent growth, antagonized the Wnt/beta-catenin signaling pathway, and repressed c-MYC expression. Cystatin D repressed expression of the epithelial-mesenchymal transition inducers SNAI1, SNAI2, ZEB1, and ZEB2 and, conversely, induced E-cadherin and other adhesion proteins. CST5 knockdown using shRNA abrogated the antiproliferative effect of 1alpha,25(OH)2D3, attenuated E-cadherin expression, and increased c-MYC expression. In human colorectal tumors, expression of cystatin D correlated with expression of VDR and E-cadherin, and loss of cystatin D correlated with poor tumor differentiation. Based on these data, we propose that CST5 has tumor suppressor activity that may contribute to the antitumoral action of 1alpha,25(OH)2D3 in colon cancer.

  18. Tumor necrosis factor-α regulates human follicular dendritic cell-secreted protein gene transcription in gingival epithelial cells.

    Science.gov (United States)

    Iwai, Yasunobu; Noda, Keisuke; Yamazaki, Mizuho; Kato, Ayako; Mezawa, Masaru; Takai, Hideki; Nakayama, Yohei; Ogata, Yorimasa

    2018-01-22

    Follicular dendritic cell-secreted protein (FDC-SP) is a secreted protein expressed in follicular dendritic cells, periodontal ligament and junctional epithelium. To elucidate the transcriptional regulation of the human FDC-SP gene by tumor necrosis factor-α (TNF-α), we conducted real-time PCR, Western blotting, transient transfection analyses with chimeric constructs of the FDC-SP gene promoter linked to a luciferase reporter gene, gel mobility shift and chromatin immunoprecipitation assays using Ca9-22 gingival epithelial cells. TNF-α (10 ng/ml) induced FDC-SP mRNA and protein levels at 3 hr and reached maximum at 12 hr. In transient transfection assays, TNF-α (12 hr) increased the LUC activities of constructs between -116FDCSP and -948FDCSP including the human FDC-SP gene promoter. Transcriptional stimulations by TNF-α were partially inhibited in the -345FDCSP constructs that included 3-bp mutations in the YY1, GATA, CCAAT enhancer-binding protein 2 (C/EBP2) and C/EBP3. Transcriptional activities induced by TNF-α were inhibited by tyrosine kinase, MEK1/2 and phosphoinositide 3-kinase inhibitors. The results of ChIP assays showed that YY1, GATA and C/EBPβ transcription factors interacted with the YY1, GATA, C/EBP2 and C/EBP3 elements that were increased by TNF-α. These studies show that TNF-α stimulates human FDC-SP gene transcription by targeting YY1, GATA, C/EBP2 and C/EBP3 in the FDC-SP gene promoter. © 2018 Molecular Biology Society of Japan and John Wiley & Sons Australia, Ltd.

  19. Tumor necrosis factor alpha and alpha-1 antitrypsin gene variants in Serbian pediatric arterial ischemic stroke patients

    Directory of Open Access Journals (Sweden)

    Đorđević Valentina

    2013-01-01

    Full Text Available The etiology of arterial ischemic stroke (AIS in children is complex, and different from that in adults. Although rare, stroke in children is an important cause of mortality and morbidity. There is increasing evidence that genetic factors, including inflammation mediators, have a role in occurrence and outcome of stroke. We have chosen to assess the role of polymorphism -308G/A in the promoter of tumor necrosis factor α (TNFα gene and S and Z mutations in alpha 1-antitrypsin (AAT gene in the etiology of stroke in children. TNFα polymorphism affects plasma levels of this proinflamatory cytokine, and this could contribute to stroke pathology. It has been shown that increased AAT concentration may present a risk for AIS in children. Since S and Z mutations in AAT gene reduce its levels in plasma they could have a protective role in pediatric stroke. In this study twenty six children with AIS and 100 unrelated individuals from Serbian general population were investigated by PCR/RFLP for these gene variations. No statistically significant difference was observed between patients and general population in distribution of genotypes for -308G/A TNFα polymorphism, so its contributory role in the etiology of stroke was not evident in our group of patients. None of the tested AAT gene mutations were found in patients, which is in concordance with the proposed protective role of deficient AAT variants. AIS is a multifactorial disease, with many genes having a modest role in its pathophysiology, so further analyses of their combined effect are needed to elucidate genetic risk factors in the etiology and outcome of stroke in pediatric patients.

  20. Role of natural antisense transcripts pertaining to tumor suppressor genes in human carcinomas

    International Nuclear Information System (INIS)

    Pelicci, G.; Pierotti, M.

    2009-01-01

    Overlapping transcripts in opposite orientations can potentially form perfect sense-antisense duplex RNA. Recently, several studies have revealed the extent of natural antisense transcripts (NATs) and their role in important biological phenomena also in higher organisms. In order to test the hypothesis that the function of NATs in man might represent an essential element in the regulation of gene expression, especially at transcriptional level, in this study we planned to look for, systematically examine, and characterize NATs belonging in the human genome to the tumour suppressor class of genes, so to identify physiological (and potentially pathological) modulators in this gene class

  1. Gene expression profiling of breast tumor cell lines to predict for therapeutic response to microtubule-stabilizing agents.

    Science.gov (United States)

    Kadra, Gais; Finetti, Pascal; Toiron, Yves; Viens, Patrice; Birnbaum, Daniel; Borg, Jean-Paul; Bertucci, François; Gonçalves, Anthony

    2012-04-01

    Microtubule-targeting agents, including taxanes (Tax) and ixabepilone (Ixa), are important components of modern breast cancer chemotherapy regimens, but no molecular parameter is currently available that can predict for their efficiency. We sought to develop pharmacogenomic predictors of Tax- and Ixa-response from a large panel of human breast tumor cell lines (BTCL), then to evaluate their performance in clinical samples. Thirty-two BTCL, representative of the molecular diversity of breast cancers (BC), were treated in vitro with Tax (paclitaxel (Pac), docetaxel (Doc)), and ixabepilone (Ixa), then classified as drug-sensitive or resistant according to their 50% inhibitory concentrations (IC50s). Baseline gene expression data were obtained using Affymetrix U133 Plus 2.0 human oligonucleotide microarrays. Gene expression set (GES) predictors of response to taxanes were derived, then tested for validation internally and in publicly available gene expression datasets. In vitro IC50s of Pac and Doc were almost identical, whereas some Tax-resistant BTCL retained sensitivity to Ixa. GES predictors for Tax-sensitivity (333 genes) and Ixa-sensitivity (79 genes) were defined. They displayed a limited number of overlapping genes. Both were validated by leave-n-out cross-validation (n = 4; for overall accuracy (OA), P = 0.028 for Tax, and P = 0.0005 for Ixa). The GES predictor of Tax-sensitivity was tested on publicly available external datasets and significantly predicted Pac-sensitivity in 16 BTCL (P = 0.04 for OA), and pathological complete response to Pac-based neoadjuvant chemotherapy in BC patients (P = 0.0045 for OA). Applying Tax and Ixa-GES to a dataset of clinically annotated early BC patients identified subsets of tumors with potentially distinct phenotypes of drug sensitivity: predicted Ixa-sensitive/Tax-resistant BC were significantly (P Tax-sensitive BC. Genomic predictors for Tax- and Ixa-sensitivity can be derived from BTCL and may be helpful for better

  2. KLF10, transforming growth factor-β-inducible early gene 1, acts as a tumor suppressor

    International Nuclear Information System (INIS)

    Song, Ki-Duk; Kim, Duk-Jung; Lee, Jong Eun; Yun, Cheol-Heui; Lee, Woon Kyu

    2012-01-01

    Highlights: ► KLF10 −/− mice exhibited accelerated papilloma development after DMBA/TPA treatment. ► KLF10 −/− keratinocytes showed increased proliferation and apoptosis. ► KLF10 −/− MEFs yielded more colonies than wild-type one with H-Ras transfection. ► KLF10 dose-dependently activated p21 WAF1/CIP1 transcription. ► KLF10 is a tumor suppressor and that it targets p21 WAF1/CIP1 transcription. -- Abstract: Krüppel-like factor 10 (KLF10) has been suggested to be a putative tumor suppressor. In the present study, we generated KLF10 deficient mice to explore this hypothesis in vivo. KLF10 deficient mice exhibited increased predisposition to skin tumorigenesis and markedly accelerated papilloma development after DMBA/TPA treatment. On the other hand, KLF10 deficient keratinocytes showed increased proliferation and apoptosis. In colony formation assays after oncogenic H-Ras transfection, KLF10 deficient mouse embryonic fibroblasts (MEFs) yielded more colonies than wild-type MEFs. Furthermore, KLF10 dose-dependently activated p21 WAF1/CIP1 transcription, which was independent of p53 and Sp1 binding sites in p21 WAF1/CIP1 promoter. This study demonstrates that KLF10 is a tumor suppressor and that it targets p21 WAF1/CIP1 transcription.

  3. Breast tumor characteristics of BRCA1 and BRCA2 gene mutation carriers on MRI

    Energy Technology Data Exchange (ETDEWEB)

    Veltman, J.; Mann, R.; Blickman, J.G.; Boetes, C. [University Medical Center, 430 Department of Radiology, P.O. Box 9101, Nijmegen (Netherlands); Kok, T. [University Medical Center, Department of Radiology, Groningen (Netherlands); Obdeijn, I.M. [Erasmus Medical Center Daniel den Hoed Cancer Center, Department of Radiology, Rotterdam (Netherlands); Hoogerbrugge, N. [University Medical Center, Department of Human Genetics, Nijmegen (Netherlands)

    2008-05-15

    The appearance of malignant lesions in BRCA1 and BRCA2 mutation carriers (BRCA-MCs) on mammography and magnetic resonance imaging (MRI) was evaluated. Thus, 29 BRCA-MCs with breast cancer were retrospectively evaluated and the results compared with an age, tumor size and tumor type matched control group of 29 sporadic breast cancer cases. Detection rates on both modalities were evaluated. Tumors were analyzed on morphology, density (mammography), enhancement pattern and kinetics (MRI). Overall detection was significantly better with MRI than with mammography (55/58 vs 44/57, P = 0.021). On mammography, lesions in the BRCA-MC group were significantly more described as rounded (12//19 vs 3/13, P = 0.036) and with sharp margins (9/19 vs 1/13, P = 0.024). On MRI lesions in the BRCA-MC group were significantly more described as rounded (16/27 vs 7/28, P = 0.010), with sharp margins (20/27 vs 7/28, P < 0.001) and with rim enhancement (7/27 vs 1/28, P = 0.025). No significant difference was found for enhancement kinetics (P = 0.667). Malignant lesions in BRCA-MC frequently have morphological characteristics commonly seen in benign lesions, like a rounded shape or sharp margins. This applies for both mammography and MRI. However the possibility of MRI to evaluate the enhancement pattern and kinetics enables the detection of characteristics suggestive for a malignancy. (orig.)

  4. Knockout of the Nogo-B Gene Attenuates Tumor Growth and Metastasis in Hepatocellular Carcinoma

    Directory of Open Access Journals (Sweden)

    Bo Zhu

    2017-07-01

    Full Text Available Human hepatocellular carcinoma (HCC is a malignant cancer. It is a challenge to develop anti-HCC drugs due to HCC's extreme aggressiveness and with the sensitivity of the liver to show severe adverse effects. More importantly, the precise mechanisms causing HCC pathogenicity are not known. Our previous study disclosed Nogo-B as a reticulon 4 (Rtn4 family member. In the present study, we first identified that Nogo-B played a critical role in HCC progression. We found, via in vitro and in vivo assays, that Nogo-B was expressed aberrantly in primary HCC tumor tissues and immortal HCC cells but was relatively scarce in the normal liver tissues or cells. Nogo-B knockout, via the CRISPR-Cas9 technique, resulted in significant suppression of HCC cell proliferation and tumor growth. Next-generation sequencing analysis showed that Nogo-B knockout have effects on interleukin-6 (IL-6 signaling pathway. Furthermore, we observed that IL-6 induced phosphorylation of STAT3 (pSTAT3 in wild-type HCC cells, but Nogo-B knockout could reduce IL-6–induced increase of pSTAT3, supporting that Nogo-B affects HCC tumor progression possibly via regulating the IL-6/STAT3 signaling pathway. In conclusion, Nogo-B is expressed aberrantly in HCCs and plays an oncogenic role. These findings support that Nogo-B may be a novel anti-HCC therapeutic target.

  5. Bifidobacterial recombinant thymidine kinase-ganciclovir gene therapy system induces FasL and TNFR2 mediated antitumor apoptosis in solid tumors

    International Nuclear Information System (INIS)

    Wang, Changdong; Ma, Yongping; Hu, Qiongwen; Xie, Tingting; Wu, Jiayan; Zeng, Fan; Song, Fangzhou

    2016-01-01

    Directly targeting therapeutic suicide gene to a solid tumor is a hopeful approach for cancer gene therapy. Treatment of a solid tumor by an effective vector for a suicide gene remains a challenge. Given the lack of effective treatments, we constructed a bifidobacterial recombinant thymidine kinase (BF-rTK) -ganciclovir (GCV) targeting system (BKV) to meet this requirement and to explore antitumor mechanisms. Bifidobacterium (BF) or BF-rTK was injected intratumorally with or without ganciclovir in a human colo320 intestinal xenograft tumor model. The tumor tissues were analyzed using apoptosis antibody arrays, real time PCR and western blot. The colo320 cell was analyzed by the gene silencing method. Autophagy and necroptosis were also detected in colo320 cell. Meanwhile, three human digestive system xenograft tumor models (colorectal cancer colo320, gastric cancer MKN-45 and liver cancer SSMC-7721) and a breast cancer (MDA-MB-231) model were employed to validate the universality of BF-rTK + GCV in solid tumor gene therapy. The survival rate was evaluated in three human cancer models after the BF-rTK + GCV intratumor treatment. The analysis of inflammatory markers (TNF-α) in tumor indicated that BF-rTK + GCV significantly inhibited TNF-α expression. The results suggested that BF-rTK + GCV induced tumor apoptosis without autophagy and necroptosis occurrence. The apoptosis was transduced by multiple signaling pathways mediated by FasL and TNFR2 and mainly activated the mitochondrial control of apoptosis via Bid and Bim, which was rescued by silencing Bid or/and Bim. However, BF + GCV only induced apoptosis via Fas/FasL signal pathway accompanied with increased P53 expression. We further found that BF-rTK + GCV inhibited the expression of the inflammatory maker of TNF-α. However, BF-rTK + GCV did not result in necroptosis and autophagy. BF-rTK + GCV induced tumor apoptosis mediated by FasL and TNFR2 through the mitochondrial control of apoptosis via Bid and Bim

  6. Nutritional Effect on Androgen-Response Gene Expression and Prostate Tumor Growth

    National Research Council Canada - National Science Library

    Wang, Zhou

    2001-01-01

    .... The dietary influence on ventral prostate weight does not seem to involve androgen action axis because dietary components did not influence the expression of several androgen-response genes, serum testosterone...

  7. Transcription of a novel mouse semaphorin gene, M-semaH, correlates with the metastatic ability of mouse tumor cell lines

    DEFF Research Database (Denmark)

    Christensen, C R; Klingelhöfer, Jörg; Tarabykina, S

    1998-01-01

    fibroblasts. To our knowledge, this is the first time that the expression of a semaphorin gene has been shown to correlate positively with tumor progression. We have characterized two transcripts present in the tumor cells. One transcript, M-semaH-v, is a putative splice variant, which is less abundant...... to the developing lungs, to developing skeletal elements, and to the ventral horns of the developing neural tube....

  8. Molecular cloning and chromosomal localization of the human cyclin C (CCNC) and cyclin E (CCNE) genes: Deletion of the CCNC gene in human tumors

    Energy Technology Data Exchange (ETDEWEB)

    Li, Haimin; Lahti, J.M.; Kidd, V.J. [St. Jude Children`s Research Hospital, Memphis, TN (United States)] [and others

    1996-03-01

    The human G1-phase cyclins are important regulators of cell cycle progression that interact with various cyclin-dependent kinases and facilitate entry into S-phase. We have confirmed the localization of the human cyclin C (CCNC) gene to chromosome 6q21 and of human cyclin E (CCNE to 19q12). The CCNC gene structure was also determined, and we have shown that it is deleted in a subset of acute lymphoblastic leukemias, including a patient sample containing a t(2;6)(p21;q15), with no apparent cytogenetic deletion. Single-strand conformational polymorphism analysis of the remaining CCNC allele from patients with a deletion of one allele established that there were no further mutations within the exons or the flanking intronic sequences. These results suggest either that haploinsufficiency of the cyclin C protein is sufficient to promote tumorigenesis or that the important tumor suppressor gene is linked to the CCNC locus. 48 refs., 4 figs., 1 tab.

  9. Transcription of a novel mouse semaphorin gene, M-semaH, correlates with the metastatic ability of mouse tumor cell lines

    DEFF Research Database (Denmark)

    Christensen, C R; Klingelhöfer, Jörg; Tarabykina, S

    1998-01-01

    In the attempt to identify genes associated with metastasis, we have compared gene expressions of two metastatic cell lines, 4T1 and 66cl4, and one noninvasive, nonmetastatic cell line, 67NR, which originate from the same mouse mammary adenocarcinoma. Using the technique of differential display, we...... identified a novel member of the semaphorin/collapsin family in the two metastatic cell lines. We have named it M-semaH. Northern hybridization to a panel of tumor cell lines revealed transcripts in 12 of 12 metastatic cell lines but in only 2 of 6 nonmetastatic cells and none in immortalized mouse...... fibroblasts. To our knowledge, this is the first time that the expression of a semaphorin gene has been shown to correlate positively with tumor progression. We have characterized two transcripts present in the tumor cells. One transcript, M-semaH-v, is a putative splice variant, which is less abundant...

  10. The Role of Tumor Metastases Suppressor Gene, Drg-1, in Breast Cancer

    Science.gov (United States)

    2007-03-01

    1μg 2.5 μg 1μg 2.5μg PC 3M M A L V A Drg-1 ATF3 Tubulin 0 200 300 0 200 300 GFP-siRNA...ceramide level in the tumor cells, and this increase was abrogated by acetyl-CoA carboxylase inhibitor. In addition, carnitine palmitoyltransferase-1...penicillin, and 250 nmol/ L dexamethasone (Sigma Chemical Co., St. Louis, MO) and grown at 37jC in a 5% CO2 atmosphere. 5-(Tetradecyloxy)-2-furoic acid (TOFA

  11. Effectiveness of circulating tumor DNA for detection of KRAS gene mutations in colorectal cancer patients: a meta-analysis

    Directory of Open Access Journals (Sweden)

    Hao Y

    2017-02-01

    Full Text Available Yi-Xin Hao,1,* Qiang Fu,2,* Yan-Yan Guo,1 Ming Ye,1 Hui-Xia Zhao,1 Qi Wang,1 Xiu-Mei Peng,1 Qiu-Wen Li,1 Ru-Liang Wang,1 Wen-Hua Xiao1 1Department of Oncology, First Affiliated Hospital, 2Department of Anesthesiology, People’s Liberation Army General Hospital, Beijing, People’s Republic of China *These authors contributed equally to this work Abstract: Circulating tumor DNA (ctDNA can be identified in the peripheral blood of patients and harbors the genomic alterations found in tumor tissues, which provides a noninvasive approach for detection of gene mutations. We conducted this meta-analysis to investigate whether ctDNA can be used for monitoring KRAS gene mutations in colorectal cancer (CRC patients. Medline, Embase, Cochrane Library and Web of Science were searched for the included eligible studies in English, and data were extracted for statistical analysis according to the numbers of true-positive (TP, true-negative (TN, false-positive (FP and false-negative (FN cases. Sensitivity, specificity and diagnostic odds ratio (DOR were calculated, and the area under the receiver operating characteristic curve (AUROC was used to evaluate the diagnostic performance. After independent searching and reviewing, 21 studies involving 1,812 cancer patients were analyzed. The overall sensitivity, specificity and DOR were 0.67 (95% confidence interval [CI] =0.55–0.78, 0.96 (95% CI =0.93–0.98 and 53.95 (95% CI =26.24–110.92, respectively. The AUROC was 0.95 (95% CI =0.92–0.96, which indicated the high diagnostic accuracy of ctDNA. After stratified analysis, we found the higher diagnostic accuracy in subgroup of patients detected in blood sample of plasma. The ctDNA may be an ideal source for detection of KRAS gene mutations in CRC patients with high specificity and diagnostic value. Keywords: cancer, KRAS, mutation, circulating tumor DNA

  12. Nuclear pore component Nup98 is a potential tumor suppressor and regulates posttranscriptional expression of select p53 target genes.

    Science.gov (United States)

    Singer, Stephan; Zhao, Ruiying; Barsotti, Anthony M; Ouwehand, Anette; Fazollahi, Mina; Coutavas, Elias; Breuhahn, Kai; Neumann, Olaf; Longerich, Thomas; Pusterla, Tobias; Powers, Maureen A; Giles, Keith M; Leedman, Peter J; Hess, Jochen; Grunwald, David; Bussemaker, Harmen J; Singer, Robert H; Schirmacher, Peter; Prives, Carol

    2012-12-14

    The p53 tumor suppressor utilizes multiple mechanisms to selectively regulate its myriad target genes, which in turn mediate diverse cellular processes. Here, using conventional and single-molecule mRNA analyses, we demonstrate that the nucleoporin Nup98 is required for full expression of p21, a key effector of the p53 pathway, but not several other p53 target genes. Nup98 regulates p21 mRNA levels by a posttranscriptional mechanism in which a complex containing Nup98 and the p21 mRNA 3'UTR protects p21 mRNA from degradation by the exosome. An in silico approach revealed another p53 target (14-3-3σ) to be similarly regulated by Nup98. The expression of Nup98 is reduced in murine and human hepatocellular carcinomas (HCCs) and correlates with p21 expression in HCC patients. Our study elucidates a previously unrecognized function of wild-type Nup98 in regulating select p53 target genes that is distinct from the well-characterized oncogenic properties of Nup98 fusion proteins. Copyright © 2012 Elsevier Inc. All rights reserved.

  13. Mutations of the CHK2 gene are found in some osteosarcomas, but are rare in breast, lung, and ovarian tumors.

    Science.gov (United States)

    Miller, Carl W; Ikezoe, Takayuki; Krug, Utz; Hofmann, Wolf-K; Tavor, Sigal; Vegesna, Vijaya; Tsukasaki, Kunihiro; Takeuchi, Seisho; Koeffler, H Phillip

    2002-01-01

    Checkpoint genes, activated in response to DNA damage and other stresses, are frequently targeted for alteration in cancer. Checkpoint kinase 2 (CHK2, CDS1, RAD53) is activated by ataxia telangiectasia mutated (ATM) in response to gamma irradiation. Activated CHK2 stabilizes TP53, and acts on other cell cycle and stress regulators. These findings place CHK2 in the middle of a pathway frequently targeted in cancer. Because of this, and the observation that CHK2 mutations are inherited in some Li-Fraumeni cancer syndrome families, we decided to examine the role of CHK2 mutations in sporadic cancers. Exploiting the genomic sequence of chromosome 22, we looked for mutations in the exons and intron junctions of the CHK2 gene in DNA samples from 170 patients (57 osteosarcomas, 25 other sarcomas, 35 nonsmall-cell lung, 20 ovarian, and 33 breast cancers). Missense mutations affecting the forkhead and kinase domains were detected in four osteosarcomas and in one ovarian and one lung cancer. These findings of CHK2 gene mutations are consistent with osteosarcoma being a defining tumor of Li-Fraumeni syndrome. The occurrence of CHK2 mutations in sporadic cancers emphasizes the importance of the stress pathway which includes TP53.

  14. Nanoparticles for siRNA-Based Gene Silencing in Tumor Therapy.

    Science.gov (United States)

    Babu, Anish; Muralidharan, Ranganayaki; Amreddy, Narsireddy; Mehta, Meghna; Munshi, Anupama; Ramesh, Rajagopal

    2016-12-01

    Gene silencing through RNA interference (RNAi) has emerged as a potential strategy in manipulating cancer causing genes by complementary base-pairing mechanism. Small interfering RNA (siRNA) is an important RNAi tool that has found significant application in cancer therapy. However due to lack of stability, poor cellular uptake and high probability of loss-of-function due to degradation, siRNA therapeutic strategies seek safe and efficient delivery vehicles for in vivo applications. The current review discusses various nanoparticle systems currently used for siRNA delivery for cancer therapy, with emphasis on liposome based gene delivery systems. The discussion also includes various methods availed to improve nanoparticle based-siRNA delivery with target specificity and superior efficiency. Further this review describes challenges and perspectives on the development of safe and efficient nanoparticle based-siRNA-delivery systems for cancer therapy.

  15. Expression profiling of formalin-fixed paraffin-embedded primary breast tumors using cancer-specific and whole genome gene panels on the DASL® platform

    Directory of Open Access Journals (Sweden)

    Cunningham Julie M

    2010-12-01

    Full Text Available Abstract Background The cDNA-mediated Annealing, extension, Selection and Ligation (DASL assay has become a suitable gene expression profiling system for degraded RNA from paraffin-embedded tissue. We examined assay characteristics and the performance of the DASL 502-gene Cancer Panelv1 (1.5K and 24,526-gene panel (24K platforms at differentiating nine human epidermal growth factor receptor 2- positive (HER2+ and 11 HER2-negative (HER2- paraffin-embedded breast tumors. Methods Bland-Altman plots and Spearman correlations evaluated intra/inter-panel agreement of normalized expression values. Unequal-variance t-statistics tested for differences in expression levels between HER2 + and HER2 - tumors. Regulatory network analysis was performed using Metacore (GeneGo Inc., St. Joseph, MI. Results Technical replicate correlations ranged between 0.815-0.956 and 0.986-0.997 for the 1.5K and 24K panels, respectively. Inter-panel correlations of expression values for the common 498 genes across the two panels ranged between 0.485-0.573. Inter-panel correlations of expression values of 17 probes with base-pair sequence matches between the 1.5K and 24K panels ranged between 0.652-0.899. In both panels, erythroblastic leukemia viral oncogene homolog 2 (ERBB2 was the most differentially expressed gene between the HER2 + and HER2 - tumors and seven additional genes had p-values |0.5| in expression between HER2 + and HER2 - tumors: topoisomerase II alpha (TOP2A, cyclin a2 (CCNA2, v-fos fbj murine osteosarcoma viral oncogene homolog (FOS, wingless-type mmtv integration site family, member 5a (WNT5A, growth factor receptor-bound protein 7 (GRB7, cell division cycle 2 (CDC2, and baculoviral iap repeat-containing protein 5 (BIRC5. The top 52 discriminating probes from the 24K panel are enriched with genes belonging to the regulatory networks centered around v-myc avian myelocytomatosis viral oncogene homolog (MYC, tumor protein p53 (TP53, and estrogen receptor

  16. The chromosome 3p21.3-encoded gene, LIMD1, is a critical tumor suppressor involved in human lung cancer development.

    Science.gov (United States)

    Sharp, Tyson V; Al-Attar, Ahmad; Foxler, Daniel E; Ding, Li; de A Vallim, Thomas Q; Zhang, Yining; Nijmeh, Hala S; Webb, Thomas M; Nicholson, Andrew G; Zhang, Qunyuan; Kraja, Aldi; Spendlove, Ian; Osborne, John; Mardis, Elaine; Longmore, Gregory D

    2008-12-16

    Loss of heterozygosity (LOH) and homozygous deletions at chromosome 3p21.3 are common in both small and nonsmall cell lung cancers, indicating the likely presence of tumor suppressor genes (TSGs). Although genetic and epigenetic changes within this region have been identified, the functional significance of these changes has not been explored. Concurrent protein expression and genetic analyses of human lung tumors coupled with functional studies have not been done. Here, we show that expression of the 3p21.3 gene, LIMD1, is frequently down-regulated in human lung tumors. Loss of LIMD1 expression occurs through a combination of gene deletion, LOH, and epigenetic silencing of transcription without evidence for coding region mutations. Experimentally, LIMD1 is a bona fide TSG. Limd1(-/-) mice are predisposed to chemical-induced lung adenocarcinoma and genetic inactivation of Limd1 in mice heterozygous for oncogenic K-Ras(G12D) markedly increased tumor initiation, promotion, and mortality. Thus, we conclude that LIMD1 is a validated chromosome 3p21.3 tumor-suppressor gene involved in human lung cancer development. LIMD1 is a LIM domain containing adapter protein that localizes to E-cadherin cell-cell adhesive junctions, yet also translocates to the nucleus where it has been shown to function as an RB corepressor. As such, LIMD1 has the potential to communicate cell extrinsic or environmental cues with nuclear responses.

  17. Does the simultaneous tumor necrosis factor receptor 2, tumor necrosis factor promoter gene polymorphism represent a higher risk for alcoholic liver disease?

    Science.gov (United States)

    Machado, Mariana Verdelho; Martins, Alexandra; Almeida, Rosário; Marques-Vidal, Pedro; Gonçalves, Maria S; Camilo, Maria E; Cortez-Pinto, Helena

    2009-02-01

    Tumor necrosis factor alpha (TNF-alpha) is a proinflammatory cytokine that seems to play a crucial role in the pathogenesis of alcoholic liver disease (ALD). TNF-alpha exerts its effects by binding to specific receptors (TNFR); the polymorphism of TNFRII T587G has been associated with increased TNF apoptotic response and its presence may increase the risk to develop liver disease. The aim of this study was to evaluate the prevalence of the TNF-alpha G238A promoter and TNFRII polymorphisms, individually or simultaneously, in ALD. TNF-alpha G238A and TNFRII T587G polymorphisms were studied in 103 unrelated patients with ALD (biopsy confirmed or clinical evidence) and in 76 heavy drinkers without liver disease (NLD). Single nucleotide polymorphism gene was detected by a polymerase chain reaction-restriction fragment length polymorphisms method. All patients had, at least, a 5 year history of alcohol consumption greater than 80 g/day. TNF-alpha G238A allele frequency was similar in both groups. TNFRII T587G allele frequency was slightly higher in the ALD group than in the NLD group (21 vs. 18%, P=NS). TNF-alpha G238A and TNFRII T587G were simultaneously present in six ALD patients and in none of NLD patients (P=0.04). Although individually there was no association between TNFRII T587G or TNF-alpha G238A polymorphisms and ALD, this study suggests that the presence of both polymorphisms may enhance the susceptibility for ALD. TNF-alpha G238A may increase TNF-alpha production, which when associated with TNFRII T587G, can further exacerbate TNF-alpha response leading to a greater risk of ALD.

  18. The tumor suppressor gene hypermethylated in cancer 1 is transcriptionally regulated by E2F1

    DEFF Research Database (Denmark)

    Jenal, Mathias; Trinh, Emmanuelle; Britschgi, Christian

    2009-01-01

    The Hypermethylated in Cancer 1 (HIC1) gene encodes a zinc finger transcriptional repressor that cooperates with p53 to suppress cancer development. We and others recently showed that HIC1 is a transcriptional target of p53. To identify additional transcriptional regulators of HIC1, we screened...

  19. Genetic variation in mitotic regulatory pathway genes is associated with breast tumor grade

    DEFF Research Database (Denmark)

    Purrington, Kristen S; Slettedahl, Seth; Bolla, Manjeet K

    2014-01-01

    Mitotic index is an important component of histologic grade and has an etiologic role in breast tumorigenesis. Several small candidate gene studies have reported associations between variation in mitotic genes and breast cancer risk. We measured associations between 2156 single nucleotide...... polymorphisms (SNPs) from 194 mitotic genes and breast cancer risk, overall and by histologic grade, in the Breast Cancer Association Consortium (BCAC) iCOGS study (n = 39 067 cases; n = 42 106 controls). SNPs in TACC2 [rs17550038: odds ratio (OR) = 1.24, 95% confidence interval (CI) 1.16-1.33, P = 4.2 × 10......(-10)) and EIF3H (rs799890: OR = 1.07, 95% CI 1.04-1.11, P = 8.7 × 10(-6)) were significantly associated with risk of low-grade breast cancer. The TACC2 signal was retained (rs17550038: OR = 1.15, 95% CI 1.07-1.23, P = 7.9 × 10(-5)) after adjustment for breast cancer risk SNPs in the nearby FGFR2 gene...

  20. Silencing of SPRY1 Triggers Complete Regression of Rhabdomyosarcoma Tumors Carrying a Mutated RAS Gene

    NARCIS (Netherlands)

    Schaaf, Gerben; Hamdi, Mohamed; Zwijnenburg, Danny; Lakeman, Arjan; Geerts, Dirk; Versteeg, Rogier; Kool, Marcel

    2010-01-01

    RAS oncogenes are among the most frequently mutated genes in human cancer, but effective strategies for therapeutic inhibition of the RAS pathway have been elusive. Sprouty1 (SPRY1) is an upstream antagonist of RAS that is activated by extracellular signal-related kinase (ERK), providing a negative

  1. [From gene to disease; tumor necrosis factor receptor and a syndrome of familial periodic fever

    NARCIS (Netherlands)

    Simon, A.; Drenth, J.P.H.; Meer, J.W.M. van der

    2001-01-01

    Familial Hibernian fever (FHF) is a rare hereditary syndrome that causes periodic attacks of fever and inflammation. It is an autosomal dominantly inherited disorder. The gene involved in FHF encodes for a receptor for tumour necrosis factor (TNFR1). These mutations are thought to result in impaired

  2. Occurrence of mutations in the epidermal growth factor receptor gene in X-ray-induced rat lung tumors

    International Nuclear Information System (INIS)

    Kitahashi, Tsukasa; Takahashi, Mami; Yamada, Yutaka

    2008-01-01

    Epidermal growth factor receptor (EGFR) gene alterations have been found in human lung cancers. However, there is no information on the factors inducing EGFR mutations. In rodents, K-ras mutations are frequently found in many lung carcinogenesis models, but hitherto, Egfr mutations have not been reported. Their presence was therefore investigated in representative lung carcinogenesis models with 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK), N-nitrosobis(2-hydroxypropyl)amine (BHP), 2-amino-3,8-dimethylimidazo[4,5-f]quinoxaline (MelQx) and ethyl carbamate (urethane), as well as X-ray irradiation. With the chemical carcinogenesis models, no mutations were detected in Egfr, which is in clear contrast to the high rates observed in either codon 12 or 61 of K-ras (21/23 of the lung tumors induced with NNK, 4/5 with MelQx, 1/4 with urethane and 7/18 with BHP). However, in the X-ray-induced lung tumors, Egfr mutations with amino acid substitution were observed in exons 18 and 21 (4/12, 33%), but no activating mutation of K-ras was detected. In addition, one and four silent mutations were identified in K-ras (exon 1) and Egfr (exons 18, 20 and 21), respectively. Most mutations in both Egfr and K-ras were G/C→A/T transitions (7/8, 88% and 31/34, 91%, respectively). Although, the mutational patterns in equivalent human lesions were not completely coincident, this first report of Egfr mutations in an experimental lung tumor model suggests that X-rays or other factors producing oxygen radicals could cause EGFR mutations in some proportion of lung cancers in humans. (author)

  3. Expression profiling of rectal tumors defines response to neoadjuvant treatment related genes.

    Directory of Open Access Journals (Sweden)

    Pablo Palma

    Full Text Available To date, no effective method exists that predicts the response to preoperative chemoradiation (CRT in locally advanced rectal cancer (LARC. Nevertheless, identification of patients who have a higher likelihood of responding to preoperative CRT could be crucial in decreasing treatment morbidity and avoiding expensive and time-consuming treatments. The aim of this study was to identify signatures or molecular markers related to response to pre-operative CRT in LARC. We analyzed the gene expression profiles of 26 pre-treatment biopsies of LARC (10 responders and 16 non-responders without metastasis using Human WG CodeLink microarray platform. Two hundred and fifty seven genes were differentially over-expressed in the responder patient subgroup. Ingenuity Pathway Analysis revealed a significant ratio of differentially expressed genes related to cancer, cellular growth and proliferation pathways, and c-Myc network. We demonstrated that high Gng4, c-Myc, Pola1, and Rrm1 mRNA expression levels was a significant prognostic factor for response to treatment in LARC patients (p<0.05. Using this gene set, we were able to establish a new model for predicting the response to CRT in rectal cancer with a sensitivity of 60% and 100% specificity. Our results reflect the value of gene expression profiling to gain insight about the molecular pathways involved in the response to treatment of LARC patients. These findings could be clinically relevant and support the use of mRNA levels when aiming to identify patients who respond to CRT therapy.

  4. Relevance of miR-21 in regulation of tumor suppressor gene PTEN in human cervical cancer cells

    International Nuclear Information System (INIS)

    Peralta-Zaragoza, Oscar; Deas, Jessica; Meneses-Acosta, Angélica; De la O-Gómez, Faustino; Fernández-Tilapa, Gloria; Gómez-Cerón, Claudia; Benítez-Boijseauneau, Odelia; Burguete-García, Ana; Torres-Poveda, Kirvis; Bermúdez-Morales, Victor Hugo; Madrid-Marina, Vicente; Rodríguez-Dorantes, Mauricio; Hidalgo-Miranda, Alfredo; Pérez-Plasencia, Carlos

    2016-01-01

    Expression of the microRNA miR-21 has been found to be altered in almost all types of cancers and it has been classified as an oncogenic microRNA or oncomir. Due to the critical functions of its target proteins in various signaling pathways, miR-21 is an attractive target for genetic and pharmacological modulation in various cancers. Cervical cancer is the second most common cause of death from cancer in women worldwide and persistent HPV infection is the main etiologic agent. This malignancy merits special attention for the development of new treatment strategies. In the present study we analyze the role of miR-21 in cervical cancer cells. To identify the downstream cellular target genes of upstream miR-21, we silenced endogenous miR-21 expression in a cervical intraepithelial neoplasia-derived cell lines using siRNAs. The effect of miR-21 on gene expression was assessed in cervical cancer cells transfected with the siRNA expression plasmid pSIMIR21. We identified the tumor suppressor gene PTEN as a target of miR-21 and determined the mechanism of its regulation throughout reporter construct plasmids. Using this model, we analyzed the expression of miR-21 and PTEN as well as functional effects such as autophagy and apoptosis induction. In SiHa cells, there was an inverse correlation between miR-21 expression and PTEN mRNA level as well as PTEN protein expression in cervical cancer cells. Transfection with the pSIMIR21 plasmid increased luciferase reporter activity in construct plasmids containing the PTEN-3′-UTR microRNA response elements MRE21-1 and MRE21-2. The role of miR-21 in cell proliferation was also analyzed in SiHa and HeLa cells transfected with the pSIMIR21 plasmid, and tumor cells exhibited markedly reduced cell proliferation along with autophagy and apoptosis induction. We conclude that miR-21 post-transcriptionally down-regulates the expression of PTEN to promote cell proliferation and cervical cancer cell survival. Therefore, it may be a

  5. Down-regulation of SFRP1 as a putative tumor suppressor gene can contribute to human hepatocellular carcinoma

    International Nuclear Information System (INIS)

    Huang, Jian; Zhang, Yun-Li; Teng, Xiao-Mei; Lin, Yun; Zheng, Da-Li; Yang, Peng-Yuan; Han, Ze-Guang

    2007-01-01

    Hepatocellular carcinoma (HCC) is one of the most common cancers in the world. SFRP1 (the secreted frizzled-related protein 1), a putative tumor suppressor gene mapped onto chromosome 8p12-p11.1, the frequent loss of heterozygosity (LOH) region in human HCC, encodes a Wingless-type (Wnt) signaling antagonist and is frequently inactivated by promoter methylation in many human cancers. However, whether the down-regulation of SFRP1 can contribute to hepatocarcinogenesis still remains unclear. We investigated the expression of SFRP1 through real time RT-PCR and immunohistochemistry staining. The cell growth and colony formation were observed as the overexpression and knockdown of SFRP1. The DNA methylation status within SFRP1 promoter was analyzed through methylation-specific PCR or bisulphate-treated DNA sequencing assays. Loss of heterozygosity was here detected with microsatellite markers. SFRP1 was significantly down-regulated in 76.1% (35/46) HCC specimens at mRNA level and in 30% (30/100) HCCs indicated by immunohistochemistry staining, as compared to adjacent non-cancerous livers. The overexpression of SFRP1 can significantly inhibit the cell growth and colony formation of YY-8103, SMMC7721, and Hep3B cells. The RNA interference against the constitutional SFRP1 in the offspring SMMC7721 cells, which were stably transfected by ectopic SFRP1, can markedly promote cell growth of these cells. LOH of both microsatellite markers D8S532 and D8SAC016868 flanking the gene locus was found in 13% (6 of 46 HCCs) and 6.5% (3 of 46 HCCs) of the informative cases, respectively, where 5 of 8 HCC specimens with LOH showed the down-regulation of SFRP1. DNA hypermethylation within SFRP1 promoter was identified in two of three HCC specimens without SFRP1 expression. Moreover, the DNA methylation of SFRP1 promoter was significantly reduced, along with the re-expression of the gene, in those HCC cell lines, Bel7404, QGY7701, and MHCC-H, as treated by DAC. Our data suggested that the

  6. Evolution and origin of merlin, the product of the Neurofibromatosis type 2 (NF2 tumor-suppressor gene

    Directory of Open Access Journals (Sweden)

    Omelyanchuk Leonid V

    2005-12-01

    Full Text Available Abstract Background Merlin, the product of the Neurofibromatosis type 2 (NF2 tumor suppressor gene, belongs to the ezrin-radixin-moesin (ERM subgroup of the protein 4.1 superfamily, which links cell surface glycoproteins to the actin cytoskeleton. While merlin's functional activity has been examined in mammalian and Drosophila models, little is understood about its evolution, diversity, and overall distribution among different taxa. Results By combining bioinformatic and phylogenetic approaches, we demonstrate that merlin homologs are present across a wide range of metazoan lineages. While the phylogenetic tree shows a monophyletic origin of the ERM family, the origin of the merlin proteins is robustly separated from that of the ERM proteins. The derivation of merlin is thought to be in early metazoa. We have also observed the expansion of the ERM-like proteins within the vertebrate clade, which occurred after its separation from Urochordata (Ciona intestinalis. Amino acid sequence alignment reveals the absence of an actin-binding site in the C-terminal region of all merlin proteins from various species but the presence of a conserved internal binding site in the N-terminal domain of the merlin and ERM proteins. In addition, a more conserved pattern of amino acid residues is found in the region containing the so-called "Blue Box," although some amino acid substitutions in this region exist in the merlin sequences of worms, fish, and Ciona. Examination of sequence variability at functionally significant sites, including the serine-518 residue, the phosphorylation of which modulates merlin's intra-molecular association and function as a tumor suppressor, identifies several potentially important sites that are conserved among all merlin proteins but divergent in the ERM proteins. Secondary structure prediction reveals the presence of a conserved α-helical domain in the central to C-terminal region of the merlin proteins of various species. The

  7. Physical mapping of chromosome 17p13.3 in the region of a putative tumor suppressor gene important in medulloblastoma

    Energy Technology Data Exchange (ETDEWEB)

    McDonald, J.D.; Daneshvar, L.; Willert, J.R. [Univ. of California, San Franciso, CA (United States)] [and others

    1994-09-01

    Deletion mapping of a medulloblastoma tumor panel revealed loss of distal chromosome 17p13.3 sequences in tumors from 14 of 32 patients (44%). Of the 14 tumors showing loss of heterozygosity by restriction fragment length polymorphism analysis, 14 of 14 (100%) displayed loss of the telomeric marker p144-D6 (D17S34), while a probe for the ABR gene on 17p13.3 was lost in 7 of 8 (88%) informative cases. Using pulsed-field gel electrophoresis, we localized the polymorphic marker (VNTR-A) of the ABR gene locus to within 220 kb of the p144-D6 locus. A cosmid contig constructed in this region was used to demonstrate by fluorescence in situ hybridization that the ABR gene is oriented transcriptionally 5{prime} to 3{prime} toward the telomere. This report provides new physical mapping data for the ABR gene, which has not been previously shown to be deleted in medulloblastoma. These results provide further evidence for the existence of a second tumor suppressor gene distinct from p53 on distal chromosome 17p. 12 refs., 3 figs.

  8. Impact of HLA-E gene polymorphism on HLA-E expression in tumor cells and prognosis in patients with stage III colorectal cancer.

    Science.gov (United States)

    Zhen, Zi-Jun; Ling, Jia-Yu; Cai, Yue; Luo, Wen-Biao; He, You-Jian

    2013-03-01

    Human leukocyte antigen (HLA)-E can contribute to the escape of cancer cells from host immune mechanisms. However, it is unknown whether HLA-E gene polymorphisms might play a role in cancer immune escape. This study aimed to evaluate the correlation between HLA-E gene polymorphisms and HLA-E expression in tumor tissue and determine the effects on clinical outcome of patients with stage III colorectal cancer. Two hundred thirty patients with stage III colorectal cancer were enrolled. HLA-E expression was detected in patient-derived tumor tissues with immunohistochemistry. HLA-E gene alleles in tumor tissues were detected with the polymerase chain reaction-sequence-specific primer method. In colorectal cancer tissue and in the normal tissue adjacent to the tumor, the HLA-E expression rates were 72.2 and 15.1 %, respectively (P HLA-E exhibited disease-free survival of 55.3, 72.9, and 72.1 %, respectively. Patients with HLA-E overexpression exhibited the lowest long-term survival rate. No relationship was observed between the type of HLA-E gene polymorphism and its expression level in tumor tissues; moreover, no polymorphisms appeared to affect the long-term survival of patients with colorectal cancer. The type of HLA-E polymorphism did not have an impact on HLA-E expression in tumors or the prognosis in patients with stage III colorectal cancer. However, the level of HLA-E expression in tumor tissue strongly predicted long-term survival in these patients.

  9. KIR Genes and Their Ligands Predict the Response to Anti-EGFR Monoclonal Antibodies in Solid Tumors.

    Science.gov (United States)

    Morales-Estevez, Cristina; De la Haba-Rodriguez, Juan; Manzanares-Martin, Barbara; Porras-Quintela, Ignacio; Rodriguez-Ariza, Antonio; Moreno-Vega, Alberto; Ortiz-Morales, Maria J; Gomez-España, Maria A; Cano-Osuna, Maria T; Lopez-Gonzalez, Javier; Chia-Delgado, Beatriz; Gonzalez-Fernandez, Rafael; Aranda-Aguilar, Enrique

    2016-01-01

    Killer-cell immunoglobulin-like receptors (KIRs) regulate the killing function of natural killer cells, which play an important role in the antibody-dependent cell-mediated cytotoxicity response exerted by therapeutic monoclonal antibodies (mAbs). However, it is unknown whether the extensive genetic variability of KIR genes and/or their human leukocyte antigen (HLA) ligands might influence the response to these treatments. This study aimed to explore whether the variability in KIR/HLA genes may be associated with the variable response observed to mAbs based anti-epidermal growth factor receptor (EGFR) therapies. Thirty-nine patients treated with anti-EGFR mAbs (trastuzumab for advanced breast cancer, or cetuximab for advanced colorectal or advanced head and neck cancer) were included in the study. All the patients had progressed to mAbs therapy and were grouped into two categories taking into account time to treatment failure (TTF ≤6 and ≥10 months). KIR genotyping (16 genetic variability) was performed in genomic DNA from peripheral blood by PCR sequence-specific primer technique, and HLA ligand typing was performed for HLA-B and -C loci by reverse polymerase chain reaction sequence-specific oligonucleotide methodology. Subjects carrying the KIR/HLA ligand combinations KIR2DS1/HLAC2C2-C1C2 and KIR3DS1/HLABw4w4-w4w6 showed longer TTF than non-carriers counterparts (14.76 vs. 3.73 months, p  KIR/HLA ligand combinations predict better response of patients to anti-EGFR therapy. These findings increase the overall knowledge on the role of specific gene variants related to responsiveness to anti-EGFR treatment in solid tumors and highlight the importance of assessing gene polymorphisms related to cancer medications.

  10. Molecular characteristics of mismatch repair genes in sporadic colorectal tumors in Czech patients

    Czech Academy of Sciences Publication Activity Database

    Vymetálková, Veronika; Slyšková, Jana; Korenková, Vlasta; Bielik, Ludovít; Langerová, Lucie; Procházka, Pavel; Rejhová, Alexandra; Schwarzová, L.; Pardini, B.; Naccarati, Alessio; Vodička, Pavel

    2014-01-01

    Roč. 15, č. 1 (2014), s. 17 ISSN 1471-2350 R&D Projects: GA AV ČR IAA500200917; GA ČR(CZ) GPP304/11/P715 Grant - others:GA MŠk(CZ) Prvouk-P27/LF1/1 Institutional support: RVO:68378041 ; RVO:86652036 Keywords : colorectal cancer * mismatch repair genes * expression levels Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 2.083, year: 2014

  11. Prediction of functionally significant single nucleotide polymorphisms in PTEN tumor suppressor gene: An in silico approach.

    Science.gov (United States)

    Khan, Imran; Ansari, Irfan A; Singh, Pratichi; Dass J, Febin Prabhu

    2017-09-01

    The phosphatase and tensin homolog (PTEN) gene plays a crucial role in signal transduction by negatively regulating the PI3K signaling pathway. It is the most frequent mutated gene in many human-related cancers. Considering its critical role, a functional analysis of missense mutations of PTEN gene was undertaken in this study. Thirty five nonsynonymous single nucleotide polymorphisms (nsSNPs) within the coding region of the PTEN gene were selected for our in silico investigation, and five nsSNPs (G129E, C124R, D252G, H61D, and R130G) were found to be deleterious based on combinatorial predictions of different computational tools. Moreover, molecular dynamics (MD) simulation was performed to investigate the conformational variation between native and all the five mutant PTEN proteins having predicted deleterious nsSNPs. The results of MD simulation of all mutant models illustrated variation in structural attributes such as root-mean-square deviation, root-mean-square fluctuation, radius of gyration, and total energy; which depicts the structural stability of PTEN protein. Furthermore, mutant PTEN protein structures also showed a significant variation in the solvent accessible surface area and hydrogen bond frequencies from the native PTEN structure. In conclusion, results of this study have established the deleterious effect of the all the five predicted nsSNPs on the PTEN protein structure. Thus, results of the current study can pave a new platform to sort out nsSNPs that can be undertaken for the confirmation of their phenotype and their correlation with diseased status in case of control studies. © 2016 International Union of Biochemistry and Molecular Biology, Inc.

  12. The Role of Tumor Metastases Suppressor Gene, Drg-1, in Breast Cancer

    National Research Council Canada - National Science Library

    Watabe, Kounosuke

    2008-01-01

    .... This inhibition leads to down-regulation of the ATF3 gene and thus suppressing metastases. We also found that a combination of NDRGI, PTEN and ATF3 is a good prognostic marker for breast cancer patients. These results suggest that the Wnt and ATF3 pathways are a potential therapeutic target for patients with metastatic disease. We will focus our next year's effort on further clarification of the NDRG1 pathway.

  13. Stromal Gene Expression and Function in Primary Breast Tumors that Metastasize to Bone Cancer

    Science.gov (United States)

    2006-07-01

    significantly altered gene ontology categories were 7 Description Common Function stefin A1 stfa1 cystatin , cathepsin inhibitor breast cancer ... cancer . Breast Cancer Res, 7: 33-36, 2005. 5. Alcaraz, J., Nelson, C . M., and Bissell, M. J. Biomechanical approaches for studying integration of...analysis of fibroblastic stromagenesis in breast cancer progression. J Mammary Gland Biol Neoplasia, 9: 311-324, 2004. 7. Kuperwasser, C ., Chavarria, T

  14. Analysis of relationship between tumor necrosis factor alpha gene (g308a polymorphism with preterm labor

    Directory of Open Access Journals (Sweden)

    Lobat Jafarzadeh

    2013-01-01

    Conclusions: There is no significant association between PTD and either maternal or fetal TNF-α −308 polymorphism and frequency ofGAmutation is not significantly increased in mothers and neonates delivered preterm. It means that the presence of this mutation by itself does not modify the overall risk of PTD. Investigations on the combination of various polymorphisms indifferent genes are recommended to achieve more accurate results.

  15. NKL homeobox gene MSX1 acts like a tumor suppressor in NK-cell leukemia.

    Science.gov (United States)

    Nagel, Stefan; Pommerenke, Claudia; Meyer, Corinna; Kaufmann, Maren; MacLeod, Roderick A F; Drexler, Hans G

    2017-09-15

    NKL homeobox gene MSX1 is physiologically expressed in lymphoid progenitors and subsequently downregulated in developing T- and B-cells. In contrast, elevated expression levels of MSX1 persist in mature natural killer (NK)-cells, indicating a functional role in this compartment. While T-cell acute lymphoblastic leukemia (T-ALL) subsets exhibit aberrant overexpression of MSX1, we show here that in malignant NK-cells the level of MSX1 transcripts is aberrantly downregulated. Chromosomal deletions at 4p16 hosting the MSX1 locus have been described in NK-cell leukemia patients. However, NK-cell lines analyzed here showed normal MSX1 gene configurations, indicating that this aberration might be uncommon. To identify alternative MSX1 regulatory mechanisms we compared expression profiling data of primary normal NK-cells and malignant NK-cell lines. This procedure revealed several deregulated genes including overexpressed IRF4, MIR155HG and MIR17HG and downregulated AUTS2, EP300, GATA3 and HHEX. As shown recently, chromatin-modulator AUTS2 is overexpressed in T-ALL subsets where it mediates aberrant transcriptional activation of MSX1. Here, our data demonstrate that in malignant NK-cell lines AUTS2 performed MSX1 activation as well, but in accordance with downregulated MSX1 transcription therein we detected reduced AUTS2 expression, a small genomic deletion at 7q11 removing exons 3 and 4, and truncating mutations in exon 1. Moreover, genomic profiling and chromosomal analyses of NK-cell lines demonstrated amplification of IRF4 at 6p25 and deletion of PRDM1 at 6q21, highlighting their potential oncogenic impact. Functional analyses performed via knockdown or forced expression of these genes revealed regulatory network disturbances effecting downregulation of MSX1 which may underlie malignant development in NK-cells.

  16. Primary microcephaly gene MCPH1 shows signatures of tumor suppressors and is regulated by miR-27a in oral squamous cell carcinoma.

    Directory of Open Access Journals (Sweden)

    Thejaswini Venkatesh

    Full Text Available Mutations in the MCPH1 (microcephalin 1 gene, located at chromosome 8p23.1, result in two autosomal recessive disorders: primary microcephaly and premature chromosome condensation syndrome. MCPH1 has also been shown to be downregulated in breast, prostate and ovarian cancers, and mutated in 1/10 breast and 5/41 endometrial tumors, suggesting that it could also function as a tumor suppressor (TS gene. To test the possibility of MCPH1 as a TS gene, we first performed LOH study in a panel of 81 matched normal oral tissues and oral squamous cell carcinoma (OSCC samples, and observed that 14/71 (19.72% informative samples showed LOH, a hallmark of TS genes. Three protein truncating mutations were identified in 1/15 OSCC samples and 2/5 cancer cell lines. MCPH1 was downregulated at both the transcript and protein levels in 21/41 (51.22% and 19/25 (76% OSCC samples respectively. A low level of MCPH1 promoter methylation was also observed in 4/40 (10% tumor samples. We further observed that overexpression of MCPH1 decreased cellular proliferation, anchorage-independent growth in soft agar, cell invasion and tumor size in nude mice, indicating its tumor suppressive function. Using bioinformatic approaches and luciferase assay, we showed that the 3'-UTR of MCPH1 harbors two non-overlapping functional seed regions for miR-27a which negatively regulated its level. The expression level of miR-27a negatively correlated with the MCPH1 protein level in OSCC. Our study indicates for the first time that, in addition to its role in brain development, MCPH1 also functions as a tumor suppressor gene an