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Sample records for oncogene mrna imaging

  1. Oncogene mRNA Imaging with Radionuclide-PNA-Peptides

    Energy Technology Data Exchange (ETDEWEB)

    Wickstrom, Eric

    2008-03-19

    New cancer gene hybridization probes to carry radionuclides were made. Noninvasive technetium-99m gamma imaging of CCND1 cancer gene activity in human breast cancer tumors in mice was demonstrated, followed by noninvasive technetium-99m imaging of MYC cancer gene activity. Noninvasive imaging of CCND1 cancer gene activity in human breast cancer tumors in mice was demonstrated with a positron-emitting copper-64 probe, followed by noninvasive positron imaging of IRS1 cancer gene activity.

  2. Imaging oncogene expression

    Energy Technology Data Exchange (ETDEWEB)

    Mukherjee, Archana [Department of Radiology, Thomas Jefferson University, Philadelphia, PA 19107 (United States)], E-mail: Archana.Mukherjee@jefferson.edu; Wickstrom, Eric [Department of Biochemistry and Molecular Biology, Thomas Jefferson University, 233S, 10th street, Philadelphia, PA 19107 (United States)], E-mail: eric@tesla.jci.tju.edu; Thakur, Mathew L. [Department of Radiology, Thomas Jefferson University, Philadelphia, PA 19107 (United States)], E-mail: Mathew.Thakur@jefferson.edu

    2009-05-15

    This review briefly outlines the importance of molecular imaging, particularly imaging of endogenous gene expression for noninvasive genetic analysis of radiographic masses. The concept of antisense imaging agents and the advantages and challenges in the development of hybridization probes for in vivo imaging are described. An overview of the investigations on oncogene expression imaging is given. Finally, the need for further improvement in antisense-based imaging agents and directions to improve oncogene mRNA targeting is stated.

  3. Identification of lung cancer oncogenes based on the mRNA expression and single nucleotide polymorphism profile data.

    Science.gov (United States)

    Wang, Y; Mei, Q; Ai, Y Q; Li, R Q; Chang, L; Li, Y F; Xia, Y X; Li, W H; Chen, Y

    2015-01-01

    This study aimed to identify the oncogenes associated with lung cancer based on the mRNA and single nucleotide polymorphism (SNP) profile data. The mRNA expression profile data of GSE43458 (80 cancer and 30 normal samples) and SNP profile data of GSE33355 (61 pairs of lung cancer samples and control samples) were downloaded from Gene Expression Omnibus database. Common genes between the mRNA profile and SNP profile were identified as the lung cancer oncogenes. Risk subpathways of the selected oncogenes with the SNP locus were analyzed using the iSubpathwayMiner package in R. Moreover, protein-protein interaction (PPI) network of the oncogenes was constructed using the HPRD database and then visualized using the Cytoscape. Totally, 3004 DEGs (1105 up-regulated and 1899 down-regulated) and 125 significant SNPs closely related to 174 genes in the lung cancer samples were identified. Also, 39 common genes, like PFKP (phosphofructokinase, platelet) and DGKH-rs11616202 (diacylglycerol kinase, eta) that enriched in sub-pathways such as galactose metabolism, fructose and mannose metabolism, and pentose phosphate pathway, were identified as the lung cancer oncogenes. Besides, PIK3R1 (phosphoinositide-3-kinase, regulatory subunit 1), RORA (RAR-related orphan receptor A), MAGI3 (membrane associated guanylate kinase, WW and PDZ domain containing 3), PTPRM (protein tyrosine phosphatase, receptor type, M), and BMP6 (bone morphogenetic protein 6) were the hub genes in PPI network. Our study suggested that PFKP and DGKH that enriched in galactose metabolism, fructose and mannose metabolism pathway, as well as PIK3R1, RORA, and MAGI3, may be the lung cancer oncogenes.

  4. Oncogenic kinase NPM/ALK induces expression of HIF1α mRNA.

    Science.gov (United States)

    Marzec, M; Liu, X; Wong, W; Yang, Y; Pasha, T; Kantekure, K; Zhang, P; Woetmann, A; Cheng, M; Odum, N; Wasik, M A

    2011-03-17

    The mechanisms of malignant cell transformation mediated by the oncogenic anaplastic lymphoma kinase (ALK) tyrosine kinase remain only partially understood. In this study, we report that T-cell lymphoma (TCL) cells carrying the nucleophosmin (NPM)/ALK fusion protein (ALK+ TCL) strongly express hypoxia-induced factor 1α (HIF1α) mRNA, even under normoxic conditions, and markedly upregulate HIF1α protein expression under hypoxia. HIF1α expression is strictly dependent on the expression and enzymatic activity of NPM/ALK, as shown in BaF3 cells transfected with wild-type NPM/ALK and kinase-inactive NPM/ALK K210R mutant and by the inhibition of the NPM/ALK function in ALK+ TCL cells by a small-molecule ALK inhibitor. NPM/ALK induces HIF1α expression by upregulating its gene transcription through its key signal transmitter signal transducer and activator of transcription 3 (STAT3), which binds to the HIF1α gene promoter as shown by the chromatin immunoprecipitation assay and is required for HIF1α gene expression as demonstrated by its small interfering RNA-mediated depletion. In turn, depletion of HIF1α increases mammalian target of rapamycin complex 1 activation, cell growth and proliferation and decreases vascular endothelial growth factor synthesis. These results identify a novel cell-transforming property of NPM/ALK, namely its ability to induce the expression of HIF1α, a protein with an important role in carcinogenesis. These results also provide another rationale to therapeutically target NPM/ALK and STAT3 in ALK+ TCL.

  5. Annotating MYC oncogene status with 89Zr-transferrin imaging

    OpenAIRE

    Holland, Jason P.; Evans, Michael J.; Rice, Samuel L.; Wongvipat, John; Sawyers, Charles L.; Lewis, Jason S.

    2012-01-01

    A non-invasive technology that quantitatively measures the activity of oncogenic signaling pathways could broadly impact cancer diagnosis and treatment using targeted therapies. Here we describe the development of 89Zr-desferrioxamine transferrin (89Zr-Tf), a novel positron emission tomography (PET) radiotracer that binds the transferrin receptor 1 (TFRC, CD71) with high avidity. 89Zr-Tf produces high contrast PET images that quantitatively reflect treatment-induced changes in MYC-regulated T...

  6. Retrieval of HPV oncogenes E6 and E7 mRNA from cervical specimens using a manual open technology protocol.

    Science.gov (United States)

    Campbell, Leonardo Martins; Pitta, Denise Rocha; De Assis, Angela Maria; Derchain, Sophie Francoise Mauricette; Campos, Elisabete Aparecida; Sarian, Luis Otavio Zanatta

    2013-01-01

    HPV oncogenes mRNA detection gains momentum as an adjuvant for HPV-related cervical abnormalities diagnosis, but is based on costly detection assays not allowing viral type targeting. To assess detection rate of HPV oncogenes E6/E7 mRNA from cervical specimens using a manual, open technology, fully customizable protocol and determine whether HPV-related epidemiological features influence mRNA retrieval. We reviewed literature and compared our retrieval rate with automated technologies. We used 60 samples positive for HPV DNA types 16, 18, 31 and/or 45. We extracted mRNA with a TRizol-based protocol, and tested mRNA purity and concentration using light absorbance. We reverse-transcribed mRNA into cDNA for E6/7 detection. HPV oncogenes E6/E7 mRNA was retrieved from 36 (60%) out of 60 specimens. No HPV load-related clinical or epidemiological feature was significantly associated with mRNA retrieval. Presence of HPV-DNA 16/18 was associated with mRNA retrieval (OR = 9.08; 95% CI 1.26 to 65.32 for HPV 16; and 18.2; IC95% 1.86 to 391.44 for HPV 18). The open-technology protocol yielded an mRNA detection rate similar to that of automated technologies. Advantages are lower costs and target HPV type customization.

  7. Effects of Hypoxanthine Substitution in Peptide Nucleic Acids Targeting KRAS2 Oncogenic mRNA Molecules: Theory and Experiment

    Science.gov (United States)

    Sanders, Jeffrey M.; Wampole, Matthew E.; Chen, Chang-Po; Sethi, Dalip; Singh, Amrita; Dupradeau, François-Yves; Wang, Fan; Gray, Brian D.; Thakur, Mathew L.; Wickstrom, Eric

    2013-01-01

    Genetic disorders can arise from single base substitutions in a single gene. A single base substitution for wild type guanine in the twelfth codon of KRAS2 mRNA occurs frequently to initiate lung, pancreatic, and colon cancer. We have observed single base mismatch specificity in radioimaging of mutant KRAS2 mRNA in tumors in mice by in vivo hybridization with radiolabeled peptide nucleic acid (PNA) dodecamers. We hypothesized that multi-mutant specificity could be achieved with a PNA dodecamer incorporating hypoxanthine, which can form Watson-Crick basepairs with adenine, cytosine, thymine, and uracil. Using molecular dynamics simulations and free energy calculations, we show that hypoxanthine substitutions in PNAs are tolerated in KRAS2 RNA-PNA duplexes where wild type guanine is replaced by mutant uracil or adenine in RNA. To validate our predictions, we synthesized PNA dodecamers with hypoxanthine, and then measured the thermal stability of RNA-PNA duplexes. Circular dichroism thermal melting results showed that hypoxanthine-containing PNAs are more stable in duplexes where hypoxanthine-adenine and hypoxanthine-uracil base pairs are formed than single mismatch duplexes or duplexes containing hypoxanthine-guanine opposition. PMID:23972113

  8. Prevalence of type-specific oncogenic human papillomavirus infection assessed by HPV E6/E7 mRNA among women with high-grade cervical lesions.

    Science.gov (United States)

    Wang, Hye-Young; Park, Sunyoung; Lee, Dongsup; Kim, Sunghyun; Kim, Geehyuk; Park, Kwang Hwa; Lee, Hyeyoung

    2015-08-01

    Human papillomavirus (HPV) infection is a major cause of premalignant dysplasia and cervical cancer. There are no data on the prevalence of genotype-specific HPV infection assessed by HPV E6/E7 mRNA in women representative of the Korean population across a broad age range. A total of 630 women aged 17-90 years were enrolled in this study. ThinPrep liquid-based cytology samples were evaluated using the CervicGen HPV RT-qDx assay, which detects 16 high-risk (HR) HPV genotypes (set 1: HPV 16, 31, 33, 35, 52, and 58; set 2: HPV 18, 39, 45, 51, 59, and 68; and set 3: HPV 53, 56, 66, and 69). The overall prevalence of HPV infection was 33.2% (n=209), and oncogenic high-risk HPV was detected in 75.9% (n=107) of 141 women with high-grade cervical lesions. HPV 16 was the most common HPV genotype among women with high-grade cervical lesions and histologically confirmed cervical intraepithelial neoplasia grade 2 and above (CIN2+) in the Republic of Korea (41.6%). Among women aged over 30 years, 182/329 (55%) had invasive cervical cancer and 135 (74%) of these were infected with oncogenic HR-HPV types (in particular 25% with HPV 16). Among patients diagnosed with CIN2+, the positivity rate of HR-HPV was the highest in women aged 40-49 years. These results suggest that the determination of specific HPV genotypes is very important for evaluating the potential impact of preventive measures, including the use of prophylactic vaccines, on reducing the burden of cervical cancer. Copyright © 2015 The Authors. Published by Elsevier Ltd.. All rights reserved.

  9. Increase in proto-oncogene mRNA transcript levels in bovine lymphoid cells infected with a cytopathic type 2 bovine viral diarrhea virus.

    Science.gov (United States)

    Neill, John D; Ridpath, Julia F

    2008-08-01

    Infection of susceptible animals with bovine viral diarrhea viruses (BVDV) can result in an array of disease symptoms that are dependent in part on the strain of infecting virus and the physiological status of the host. BVDV are lymphotrophic and exist as two biotypes. Cytopathic BVDV kill cells outright while noncytopathic strains can readily establish persistent infections. The molecular mechanisms behind these different affects are unknown. To gain a better understanding of the mechanisms of disease, serial analysis of gene expression (SAGE), a powerful method for global gene expression analysis, was employed to examine gene expression changes in BVDV-infected BL3 cells, a bovine B-cell lymphosarcoma cell line. SAGE libraries were constructed from mRNA derived from BL3 cells that were noninfected or infected with the cytopathic BVDV2 strain 296c. Annotation of the SAGE data showed the expression of many genes that are characteristic of B cells and integral to their function. Comparison of the SAGE databases also revealed a number of genes that were differentially expressed. Of particular interest was the increased numbers of transcripts encoding proto-oncogenes (c-fos, c-jun, junB, junD) in 296c-infected cells, all of which are constituents of the AP-1 transcriptional activation complex. Real-time RT-PCR confirmed these results and indicated that the actual increases were larger than that predicted by SAGE. In contrast, there was no corresponding increase in protein levels, but instead a significant decrease of c-jun and junB protein levels in the infected BL3 cells was observed. Rather than an increase in transcription of these genes, it appeared that these proto-oncogenes transcripts accumulated in the BVDV2-infected cells.

  10. Imaging mRNA and protein interactions within neurons

    Science.gov (United States)

    Eliscovich, Carolina; Shenoy, Shailesh M.

    2017-01-01

    RNA–protein interactions are essential for proper gene expression regulation, particularly in neurons with unique spatial constraints. Currently, these interactions are defined biochemically, but a method is needed to evaluate them quantitatively within morphological context. Colocalization of two-color labels using wide-field microscopy is a method to infer these interactions. However, because of chromatic aberrations in the objective lens, this approach lacks the resolution to determine whether two molecules are physically in contact or simply nearby by chance. Here, we developed a robust super registration methodology that corrected the chromatic aberration across the entire image field to within 10 nm, which is capable of determining whether two molecules are physically interacting or simply in proximity by random chance. We applied this approach to image single-molecule FISH in combination with immunofluorescence (smFISH-IF) and determined whether the association between an mRNA and binding protein(s) within a neuron was significant or accidental. We evaluated several mRNA-binding proteins identified from RNA pulldown assays to determine which of these exhibit bona fide interactions. Surprisingly, many known mRNA-binding proteins did not bind the mRNA in situ, indicating that adventitious interactions are significant using existing technology. This method provides an ability to evaluate two-color registration compatible with the scale of molecular interactions. PMID:28223507

  11. Investigation of oncogenic cooperation in simple liver-specific transgenic mouse models using noninvasive in vivo imaging.

    Directory of Open Access Journals (Sweden)

    Hye-Lim Ju

    Full Text Available Liver cancer is a complex multistep process requiring genetic alterations in multiple proto-oncogenes and tumor suppressor genes. Although hundreds of genes are known to play roles in hepatocarcinogenesis, oncogenic collaboration among these genes is still largely unknown. Here, we report a simple methodology by which oncogenic cooperation between cancer-related genes can be efficiently investigated in the liver. We developed various non-germline transgenic mouse models using hydrodynamics-based transfection which express HrasG12V, SmoM2, and a short-hairpin RNA down-regulating p53 (shp53 individually or in combination in the liver. In this transgenic system, firefly luciferase was co-expressed with the oncogenes as a reporter, allowing tumor growth in the liver to be monitored over time without an invasive procedure. Very strong bioluminescence imaging (BLI signals were observed at 4 weeks post-hydrodynamic injection (PHI in mice co-expressing HrasG12V and shp53, while only background signals were detected in other double or single transgenic groups until 30 weeks PHI. Consistent with the BLI data, tumors were observed in the HrasG12V plus shp53 group at 4 weeks PHI, while other transgenic groups failed to exhibit a hyperplastic nodule at 30 weeks PHI. In the HrasG12V plus shp53 transgenic group, BLI signals were well-correlated with actual tumor growth in the liver, confirming the versatility of BLI-based monitoring of tumor growth in this organ. The methodology described here is expected to accelerate and facilitate in vivo studies of the hepatocarcinogenic potential of cancer-related genes by means of oncogenic cooperation.

  12. Ribozyme对癌基因ki-rasG12V mRNA的剪切及其特异性%Cleavage of Oncogene ki-rasG12V mRNA by Ribozyme and It' s Specificity

    Institute of Scientific and Technical Information of China (English)

    吴国祥; 方裕强; 许国铭; 李兆申; 陆德如

    2000-01-01

    目的:设计切割ki-rasG12vmRNA的特异性ribozyme(Rz217),明确其对癌基因ki-rasG12VmRNA的细胞内外切割活性,为以ki-rasG12VmRNA为特异性靶分子的基因治疗及癌基因ki-ras的功能研究提拱一种新的途径。方法:依Symons总结的"锤头结构"原理,设计一种能特异性切割ki-rasG12VmRNA的ribozyme,利用DNA重组技术构建ki-rasG12V外显子1和ri-bozyme Rz217的体外转录质粒及ribozyme Rz217的真核表达质粒,体外转录获得ribozyme Rz217及ki-rasG12V外显子1 mRNA,在含Mg2+溶液中ribozyme Rz217对其靶RNA分子进行切割。以RT-PCR对转染ribozyme Rz217真核表达质粒的细胞ki-rasG12VmRNA进行半定量分析。结果:ki-rasG12V外显子1体外转录mRNA分子,能被ribozyme Rz217定点切割而野生型ki-ras外显子1体外转录mRNA则不被切割;转染ribozyme Rz217的胰癌细胞ki-rasG12VmRNA含量减少,而转染ribozyme Re217的肝癌细胞其内源性ki-ras mRNA含量无明显变化。结论:ribozyme Rz217无论在细胞内外均能剪切突变型ki-ras mRNA(G12V)而且其切割作用为突变型ki-rasG12VmRNA特异性的。%Objective: To design and confirm the cleavage activity of ribozyme Rz217 to oncogene ki-rasG12V messenger RNA and search for a new method for gene therapy targeting oncogene ki-ras. Methods: According to Symon' s principle,design an ribozyme specific for ki-rasc12v mRNA, both the constructs for transcription in vitro of ribozyme Rz217 and ki-ras exonl and the mammalian expression constructs of ribozyme Rz217 were constructed by DNA recombinant technique,ribozyme Rz217 and ki-ras exonl mRNA was obtained by transcription in vitro with T7 and SP6 RNA polymerase. Pancre atic carcinoma cell line PaTu8988 and human hepatocellular carcinomacell line BEL7404 were transfected with Rz217 mammalian expression constructs and the level of endogenous ki-rasG12V mRNA or ki-ras mRNA was determined by semiquantitative RT-PCR. Results: Not only in vitro

  13. Real time imaging of mRNA expression dynamics in live cells using protein complementation methods

    Science.gov (United States)

    Meller, Amit

    2009-03-01

    Traditional methods for mRNA quantification in cells, such as northern blots, quantitative PCR or microarrays assays, require cell lysis and therefore do not preserve its dynamics. These methods cannot be used to probe the spatio-temporal localization of mRNA in cells, which provide useful information for a wide range biomolecular process, including RNA metabolizim, expression kinetics and RNA interference. To probe mRNA dynamics in live prokaryotic and eukaryotic cells, we develop a method, which exploit the strong affinity of the eukaryotic initiation factor 4A (eIF4A) to specific RNA aptamers. Two parts of the eIF4A are fused to a split Green Fluorescence Protein (GFP), and are expressed in the cells at high abundance. However, only when the RNA apatmer is also present, the two protein parts complement and become fluorescent. Thus, the fluorescent background remains low, allowing us to directly image the expression of mRNA molecules in live e-coli cells from its early onset, over hours. We find that the expression kinetics can be classified in one out of at least three forms, which also display distinct spatial distributions. I will discuss the possible biological origin for these distributions and their time evolution.

  14. Quantitative imaging of single mRNA splice variants in living cells

    Science.gov (United States)

    Lee, Kyuwan; Cui, Yi; Lee, Luke P.; Irudayaraj, Joseph

    2014-06-01

    Alternative messenger RNA (mRNA) splicing is a fundamental process of gene regulation, and errors in RNA splicing are known to be associated with a variety of different diseases. However, there is currently a lack of quantitative technologies for monitoring mRNA splice variants in cells. Here, we show that a combination of plasmonic dimer probes and hyperspectral imaging can be used to detect and quantify mRNA splice variants in living cells. The probes are made from gold nanoparticles functionalized with oligonucleotides and can hybridize to specific mRNA sequences, forming nanoparticle dimers that exhibit distinct spectral shifts due to plasmonic coupling. With this approach, we show that the spatial and temporal distribution of three selected splice variants of the breast cancer susceptibility gene, BRCA1, can be monitored at single-copy resolution by measuring the hybridization dynamics of the nanoplasmonic dimers. Our study provides insights into RNA and its transport in living cells, which could improve our understanding of cellular protein complexes, pharmacogenomics, genetic diagnosis and gene therapies.

  15. In Vivo Imaging-Based Mathematical Modeling Techniques That Enhance the Understanding of Oncogene Addiction in relation to Tumor Growth

    Directory of Open Access Journals (Sweden)

    Chinyere Nwabugwu

    2013-01-01

    Full Text Available The dependence on the overexpression of a single oncogene constitutes an exploitable weakness for molecular targeted therapy. These drugs can produce dramatic tumor regression by targeting the driving oncogene, but relapse often follows. Understanding the complex interactions of the tumor’s multifaceted response to oncogene inactivation is key to tumor regression. It has become clear that a collection of cellular responses lead to regression and that immune-mediated steps are vital to preventing relapse. Our integrative mathematical model includes a variety of cellular response mechanisms of tumors to oncogene inactivation. It allows for correct predictions of the time course of events following oncogene inactivation and their impact on tumor burden. A number of aspects of our mathematical model have proven to be necessary for recapitulating our experimental results. These include a number of heterogeneous tumor cell states since cells following different cellular programs have vastly different fates. Stochastic transitions between these states are necessary to capture the effect of escape from oncogene addiction (i.e., resistance. Finally, delay differential equations were used to accurately model the tumor growth kinetics that we have observed. We use this to model oncogene addiction in MYC-induced lymphoma, osteosarcoma, and hepatocellular carcinoma.

  16. Imaging single mRNAs to study dynamics of mRNA export in the yeast Saccharomyces cerevisiae.

    Science.gov (United States)

    Bensidoun, Pierre; Raymond, Pascal; Oeffinger, Marlene; Zenklusen, Daniel

    2016-04-01

    Regulation of mRNA and protein expression occurs at many levels, initiated at transcription and followed by mRNA processing, export, localization, translation and mRNA degradation. The ability to study mRNAs in living cells has become a critical tool to study and analyze how the various steps of the gene expression pathway are carried out. Here we describe a detailed protocol for real time fluorescent RNA imaging using the PP7 bacteriophage coat protein, which allows mRNA detection with high spatial and temporal resolution in the yeast Saccharomyces cerevisiae, and can be applied to study various stages of mRNA metabolism. We describe the different parameters required for quantitative single molecule imaging in yeast, including strategies for genomic integration, expression of a PP7 coat protein GFP fusion protein, microscope setup and analysis strategies. We illustrate the method's use by analyzing the behavior of nuclear mRNA in yeast and the role of the nuclear basket in mRNA export.

  17. Sensitivity of APTIMA HPV E6/E7 mRNA test in comparison with hybrid capture 2 HPV DNA test for detection of high risk oncogenic human papillomavirus in 396 biopsy confirmed cervical cancers.

    Science.gov (United States)

    Basu, Partha; Banerjee, Dipanwita; Mittal, Srabani; Dutta, Sankhadeep; Ghosh, Ishita; Chowdhury, Nilarun; Abraham, Priya; Chandna, Puneet; Ratnam, Sam

    2016-07-01

    The sensitivity of E6/E7 mRNA-based Aptima HPV test (AHPV; Hologic, Inc.) for detection of cervical cancer has been reported based on only a small number of cases. We determined the sensitivity of AHPV in comparison with the DNA-based Hybrid Capture 2 HPV test (HC2; Qiagen) for the detection of oncogenic HPV in a large number of cervical cancers at the time of diagnosis using cervical samples obtained in ThinPrep (Hologic). Samples yielding discordant results were genotyped using Linear Array assay (LA; Roche). Of 396 cases tested, AHPV detected 377 (sensitivity, 95.2%; 95%CI: 93.1-97.3), and HC2 376 (sensitivity, 94.9%; 95%CI: 92.7-97.1) with an agreement of 97.2% (kappa 0.7; 95%CI: 0.54-0.87). Among six AHPV+/HC2- cases, LA identified oncogenic HPV types in four including a type 73 and was negative in two. Among five AHPV-/HC2+ cases, LA detected oncogenic HPV types in two including a type 73 and was negative in three. Of 14 AHPV-/HC2- cases, 13 were genotyped. LA detected oncogenic HPV types in six, non-oncogenic types in three, and was negative in four. This is the largest study to demonstrate the sensitivity of AHPV for the detection of invasive cervical cancer and this assay showed equal sensitivity to HC2.

  18. Imaging Real-Time Gene Expression in Living Systems with Single-Transcript Resolution: Single mRNA Particle Tracking with ImageJ-Based Analysis.

    Science.gov (United States)

    Wells, Amber L; Condeelis, John S; Singer, Robert H; Zenklusen, Daniel

    2007-11-01

    INTRODUCTIONThis protocol describes the use of ImageJ software (freely available from NIH) to analyze particle dynamics in a cell using time-lapse movie frames or image stacks of fluorescent mRNA particles. Maximum intensity projections and kymographs are produced.

  19. 垂体生长激素腺瘤中gsp癌基因对GHSR-1a、Ghrelin mRNA表达的影响%Effect of gsp oncogene on expression of GHSR - 1a and Ghrelin mRNA in human GH - secreting pituitary adenomas

    Institute of Scientific and Technical Information of China (English)

    徐同江; 叶飞; 田春雷; 谢蕊繁; 舒凯; 郭东生; 雷霆

    2010-01-01

    目的 研究垂体生长激素(GH)腺瘤组织中Ghrelin、生长激素释放剂受体-1a亚型(GHSR-1a)mRNA的表达,并探讨其表达与gsp癌基因的关系.方法 采用PCR-DNA直接序列分析方法,观察43例垂体GH腺瘤组织中gsp癌基因的表达;应用实时荧光定量PCR检测Ghrelin和GHSR-1a mRNA的表达水平;统计学分析Ghrelin和GHSR-1a mRNA表达与gsp癌基因的关系.结果 Ghrelin mRNA表达在gsp癌基因阳性、阴性组织间差异无统计学意义(P>0.05);gsp阳性组织中GHSR-1a mRNA表达明显高于gsp阴性组织(P<0.05);gsp阳性、阴性腺瘤组织中GHSR-1amRNA与Ghrelin mRNA的表达均呈明显正相关(R=0.592或0.544,P<0.05).结论 垂体GH腺瘤中gsp癌基因上调GHSR-1a mRNA的表达;而对Ghrelin mRNA表达无明显影响.gsp阳性、阴性腺瘤中Ghrelin均可正向调控GHSR-1a mRNA表达.%Objective To investigate the relationship between the expression of growth hormone secretagogue receptor type 1a (GHSR- 1a) 、Ghrelin mRNA and gsp oncogene in human GH- secreting pituitary adenomas. Methods The gsp oncogene mutation in 43 cases of GH -secreting pituitary adenomas was detected by PCR - DNA direct sequencing analysis. The expression of GHSR - 1a、Ghrelin mRNA was determined by SYBR green real -time fluorescent quantitative PCR. Then the relationships between the expression of GHSR -1a、Ghrelin mRNA and gsp oncegene were studied with statistical methods. Results There was no significant difference in the expression of ghrelin mRNA between mutation - positive and mutation - negative adenomas. The expression of GHSR - 1a mRNA was significantly higher in gsp - positive adenomas than that in gsp - negative adenomas. There was significant direct correlation between the levels of ghrelin mRNA and GHSR mRNA expression in gsp - positive and gsp - negative adenomas. Conclusions Gsp oncogene may up - regulate the expression of GHSR - 1a mRNA and has no effect on the expression of ghrelin mRNA in human GH

  20. Temporal and spatial regulation of mRNA export: Single particle RNA-imaging provides new tools and insights.

    Science.gov (United States)

    Heinrich, Stephanie; Derrer, Carina Patrizia; Lari, Azra; Weis, Karsten; Montpetit, Ben

    2017-02-01

    The transport of messenger RNAs (mRNAs) from the nucleus to cytoplasm is an essential step in the gene expression program of all eukaryotes. Recent technological advances in the areas of RNA-labeling, microscopy, and sequencing are leading to novel insights about mRNA biogenesis and export. This includes quantitative single molecule imaging (SMI) of RNA molecules in live cells, which is providing knowledge of the spatial and temporal dynamics of the export process. As this information becomes available, it leads to new questions, the reinterpretation of previous findings, and revised models of mRNA export. In this review, we will briefly highlight some of these recent findings and discuss how live cell SMI approaches may be used to further our current understanding of mRNA export and gene expression. © 2017 WILEY Periodicals, Inc.

  1. REAL-TIME DETECTION OF SURVIVIN mRNA EXPRESSION IN CERVICAL CANCER CELL LINES USING MOLECULAR BEACON IMAGING

    Institute of Scientific and Technical Information of China (English)

    An Ruifang; He Dalin; Xue Yan; Wang Shu; Xie Li; Zhao Jun; Wang Xinyang; Yang Lili

    2006-01-01

    Objective To detect the expression of survivin mRNA in cervical cancer cell lines using molecular beacon imaging technology. Methods Human cervical cancer cells (HeLa and SiHa) and human fetal lung fibroblast HFL-I were cultured in vitro. After adding 100 nmol/L survivin mRNA molecular beacon, the fluorescent signals were observed under fluorescent microscope. The expressions of survivin in cervical cancer cells and HFL-I cell were examined by immunocytochemical streptravidin-biothin peroxidase (SP) assay at the same time. Results Two kinds of survivin mRNA molecular beacon, with different color fluorescence, had strong fluorescent signal in cervical cancer cell lines, and the signal in SiHa cell line was stronger, but these signals were not found in HFL-I ; Immunocytochemical staining of positive survivin was located in the cytoplasm of cervical cancer cell lines HeLa and SiHa, whereas, no expression of survivin was detected in HFL-I cell line. Conclusion The technology of molecular beacon imaging can be used to detect the expression of survivin mRNA in viable cells successfully, and may provide a new approach to the diagnosis of early stage cervical cancer and the following-up in the clinic.

  2. Determinants of viral oncogenes E6-E7 mRNA over-expression in a population-based large sample of women infected by high risk HPV types.

    Science.gov (United States)

    Giorgi Rossi, Paolo; Bisanzi, Simonetta; Allia, Elena; Mongia, Alessandra; Carozzi, Francesca; Gillio-Tos, Anna; De Marco, Laura; Ronco, Guglielmo; Gustinucci, Daniela; Del Mistro, Annarosa; Frayle, Helena; Iossa, Anna; Fantacci, Giulia; Pompei, Giampaolo; Cesarini, Elena; Bulletti, Simonetta; Passamonti, Basilio; Rizzi, Martina; Penon, Maria Gabriella; Barca, Alessandra; Benevolo, Maria

    2017-01-18

    Cervical cancer screening by HPV-DNA testing with cytology triage is more effective than cytology testing. Compared to cytology, the HPV-DNA test higher sensitivity, that allows better protection with longer intervals, makes it necessary to triage the women with a positive result to compensate its lower specificity.We are conducting a large randomized clinical trial (New Technologies for Cervical Cancer 2, NTCC2) within organized population-based screening programs in Italy using HPV-DNA as primary screening test, to evaluate, by Aptima HPV Assay (Hologic), HPV E6-E7 mRNA as triage test in comparison to cytology.By the end of June 2016, data are available for 35877 out of 38535enrolled women, 2651 (7.4%) of whom are HPV-DNA positive. Among them, 2453 samples were tested also by Aptima, and 1649 (67.2%) gave a positive result. The proportion of mRNA positivity was slightly higher among samples tested for HPV-DNA by Cobas 4800 HPV (Roche) than by HC2 assay (Qiagen) .In our setting, the observed E6-E7 mRNA positivity rate, if used as a triage test, would bring to an immediate referral to colposcopy of about 4-5%. This value is higher than that observed with cytology triage for both immediate and delayed referral to colposcopy. Only showing a very high sensitivity, thus allowing longer interval for HPV-DNA positive/HPV-mRNA negative women, a triage by this test might be efficient in comparison to cytology.

  3. Oncogenic viruses and cancer

    Institute of Scientific and Technical Information of China (English)

    Guangxiang; George; Luo; Jing-hsiung; James; Ou

    2015-01-01

    <正>This special issue of the journal is dedicated to the important topic of oncogenic viruses and cancer.It contains seven review articles covering all known oncogenic viruses except for human T-lymphotropic virus type1(HTLV-1).These review articles are contributed by experts on specific viruses and their associated human cancers.Viruses account for about 20%of total human cancer cases.Although many viruses can cause various tumors in animals,only seven of them

  4. Identification of a provirally activated c-Ha-ras oncogene in an avian nephroblastoma via a novel procedure: cDNA cloning of a chimaeric viral-host transcript.

    Science.gov (United States)

    Westaway, D; Papkoff, J; Moscovici, C; Varmus, H E

    1986-01-01

    Retrovirus without oncogenes often exert their neoplastic potential as insertional mutagens of cellular proto-oncogenes. This may be associated with the production of chimaeric viral-host transcripts; in these cases; activated cellular genes can be identified by obtaining cDNA clones of bipartite RNAs. This approach was used in the analysis of chicken nephroblastomas induced by myeloblastosis-associated virus (MAV). One tumor contained a novel mRNA species initiated within a MAV LTR. cDNA cloning revealed that this mRNA encodes a protein of 189 amino acids, identical to that of normal human Ha-ras-1 at 185 positions, including positions implicated in oncogenic activation of ras proto-oncogenes; there are no differences between the coding sequences of presumably normal Ha-ras cDNA clones from chicken lymphoma RNA and the tumor-derived cDNAs. The chimaeric mRNA in the nephroblastoma is at least 25-fold more abundant than c-Ha-ras mRNA in normal kidney tissue, and a 21-kd ras-related protein is present in relatively large amounts in the tumor. We conclude that a quantitative change in c-Ha-ras gene expression results from an upstream insertion mutation and presumably contributes to tumorigenesis in this single case. Little or no increase in c-Ha-ras RNA or protein was observed in other nephroblastomas. Images Fig. 2. Fig. 3. Fig. 4. Fig. 5. Fig. 6. Fig. 10. PMID:3011401

  5. Relationship between the high-risk HPV infection and the expression of oncogenes, anti-oncogenes in cervical dysplasia

    Institute of Scientific and Technical Information of China (English)

    Li-Ping Shi; Xiu-Jie Sheng

    2017-01-01

    Objective:To study the relationship between the infection of high-risk HPV in cervical precancerous lesion and the expression of oncogene, anti-oncogene.Methods:218 cases ofcervical intraepithelial neoplasia patients in our hospital during May 2014–May 2016 were chosed and divided into high-risk HPV group (n=107), low-risk HPV group (n=111) according to cervical tissue HPV test; another 100 cases of patients received cervical biopsy and confirmed as benign lesions were enrolled in the control group. RT-PCR method was used to detect the mRNA expression of proto-oncogene and anti-oncogene in three groups, Western-blot method was used to detect the protein expression of Sox-2 and Wnt/β-catenin signal pathway.Results: mRNA expression of oncogene DEK, Bmi-1, c-fos, K-ras, Prdx4 in high-risk HPV group were higher than low-risk HPV group and control group (P<0.05); mRNA expression of anti-oncogene P27, P16, DAPK, PTEN, eIF4E3 in high-risk HPV group were lower than low-risk HPV group and control group (P<0.05); expression of Sox-2 and Wnt/β-catenin signaling pathway protein Sox-2,β-catenin, wnt-1, wnt-3a in high-risk HPV group were higher than low-risk HPV group and control group (P<0.05).Conclusions:High-risk HPV infection can increase the expression of oncogenes and reduce the expression of anti-oncogenes in cervical dysplasia tissues on Sox-2- and Wnt/β-catenin signaling pathway manners.

  6. Pesticides and oncogenic modulation.

    Science.gov (United States)

    Vakonaki, Elena; Androutsopoulos, Vasilis P; Liesivuori, Jyrki; Tsatsakis, Aristidis M; Spandidos, Demetrios A

    2013-05-10

    Pesticides constitute a diverse class of chemicals used for the protection of agricultural products. Several lines of evidence demonstrate that organochlorine and organophosphate pesticides can cause malignant transformation of cells in in vitro and in vivo models. In the current minireview a comprehensive summary of recent in vitro findings is presented along with data reported from human population studies, regarding the impact of pesticide exposure on activation or dysregulation of oncogenes and tumor suppressor genes. Substantial mechanistic work suggests that pesticides are capable of inducing mutations in oncogenes and increase their transcriptional expression in vitro, whereas human population studies indicate associations between pesticide exposure levels and mutation occurrence in cancer-related genes. Further work is required to fully explore the exact mechanisms by which pesticide exposure affects the integrity and normal function of oncogenes and tumor suppressor genes in human populations.

  7. Electrostatic nucleic acid nanoassembly enables hybridization chain reaction in living cells for ultrasensitive mRNA imaging.

    Science.gov (United States)

    Wu, Zhan; Liu, Gao-Qin; Yang, Xiao-Li; Jiang, Jian-Hui

    2015-06-03

    Efficient approaches for intracellular delivery of nucleic acid reagents to achieve sensitive detection and regulation of gene and protein expressions are essential for chemistry and biology. We develop a novel electrostatic DNA nanoassembly that, for the first time, realizes hybridization chain reaction (HCR), a target-initiated alternating hybridization reaction between two hairpin probes, for signal amplification in living cells. The DNA nanoassembly has a designed structure with a core gold nanoparticle, a cationic peptide interlayer, and an electrostatically assembled outer layer of fluorophore-labeled hairpin DNA probes. It is shown to have high efficiency for cellular delivery of DNA probes via a unique endocytosis-independent mechanism that confers a significant advantage of overcoming endosomal entrapment. Moreover, electrostatic assembly of DNA probes enables target-initialized release of the probes from the nanoassembly via HCR. This intracellular HCR offers efficient signal amplification and enables ultrasensitive fluorescence activation imaging of mRNA expression with a picomolar detection limit. The results imply that the developed nanoassembly may provide an invaluable platform in low-abundance biomarker discovery and regulation for cell biology and theranostics.

  8. [Correlation between the mRNA expression of tissue inhibitor of metalloproteinase-1 and apparent diffusion coefficient on diffusion-weighted imaging in rats' liver fibrosis].

    Science.gov (United States)

    Zhan, Yuefu; Liang, Xianwen; Han, Xiangjun; Chen, Jianqiang; Zhang, Shufang; Tan, Shun; Li, Qun; Wang, Xiong; Liu, Fan

    2017-02-28

    To explore the correlation between the apparent diffusion coefficient (ADC) and mRNA expression of tissue inhibitor of metalloproteinase-1 (TIMP-1) in different stages of liver fibrosis in rats.
 Methods: A model of liver fibrosis in rats was established by intraperitoneal injection of high-fat diet combined with porcine serum. After drug administration for 4 weeks, 48 rats served as a model group and 12 rats served as a control group, then they underwent diffusion weighted imaging (DWI) scanning. The value of ADC was calculated at b value=800 s/mm2. The rats were sacrificed and carried out pathologic examination after DWI scanning immediately. The mRNA expression of TIMP-1 was detected by real time-polymerase chain reaction (RT-PCR). The rats of hepatic fibrosis were also divided into a S0 group (n=4), a S1 group (n=11), a S2 group (n=12), a S3 group (n=10), and a S4 group (n=9) according to their pathological stage. The value of ADC and the expression of TIMP-1 mRNA among the different stage groups of liver fibrosis were compared, and the correlation between ADC and the TIMP-1 mRNA were analyzed.
 Results: The ADC value and the TIMP-1 mRNA expression were significantly different between the control group and the liver fibrosis group (F=46.54 and 53.87, P0.05). For the comparison of TIMP-1 mRNA, there was no significant difference between the S1 group and the S2 group, the S3 group and the S4 group (both P>0.05). There were significant differences among the rest of the groups (all Pcorrelation analysis showed that there was a negative correlation between the ADC value and the TIMP-1 mRNA expression (r=-0.76, Pcorrelation between them.

  9. Assessment of human papillomavirus E6/E7 oncogene expression as cervical disease biomarker

    National Research Council Canada - National Science Library

    Fontecha, Nerea; Basaras, Miren; Hernáez, Silvia; Andía, Daniel; Cisterna, Ramón

    2016-01-01

    .... After RNA extraction, E6/E7 oncogene mRNA detection was performed by NucliSens[R] EasyQ[R] HPV v1 Test (bioM#241;rieux). The results of the present study showed that E6/E7 mRNA positivity rate...

  10. Oncogenes in melanoma: an update.

    Science.gov (United States)

    Kunz, Manfred

    2014-01-01

    Melanoma is a highly aggressive tumour with poor prognosis in the metastatic stage. BRAF, NRAS, and KIT are three well-known oncogenes involved in melanoma pathogenesis. Targeting of mutated BRAF kinase has recently been shown to significantly improve overall survival of metastatic melanoma patients, underscoring the particular role of this oncogene in melanoma biology. However, recurrences regularly occur within several months, which supposedly involve further oncogenes. Moreover, oncogenic driver mutations have not been described for up to 30% of all melanomas. In order to obtain a more complete picture of the mutational landscape of melanoma, more recent studies used high-throughput DNA sequencing technologies. A number of new oncogene candidates such as MAPK1/2, ERBB4, GRIN2A, GRM3, RAC1, and PREX2 were identified. Their particular role in melanoma biology is currently under investigation. Evidence for the functional relevance of some of these new oncogene candidates has been provided in in vitro and in vivo experiments. However, these findings await further validation in clinical studies. This review provides an overview on well-known melanoma oncogenes and new oncogene candidates, based on recent high-throughput sequencing studies. The list of genes discussed herein is of course not complete but highlights some of the most significant of recent findings in this area. The new candidates may support more individualized treatment approaches for metastatic melanoma patients in the future.

  11. Regulation of glut1 mRNA by hypoxia-inducible factor-1. Interaction between H-ras and hypoxia

    National Research Council Canada - National Science Library

    Chen, C; Pore, N; Behrooz, A; Ismail-Beigi, F; Maity, A

    2001-01-01

    Oncogenic transformation and hypoxia both induce glut1 mRNA. We studied the interaction between the ras oncogene and hypoxia in up-regulating glut1 mRNA levels using Rat1 fibroblasts transformed with H-ras (Rat1-ras...

  12. Development of Peptide Nucleic Acid Probes for Detection of the HER2 Oncogene

    Science.gov (United States)

    Song, Young K.; Evangelista, Jennifer; Aschenbach, Konrad; Johansson, Peter; Wen, Xinyu; Chen, Qingrong; Lee, Albert; Hempel, Heidi; Gheeya, Jinesh S.; Getty, Stephanie; Gomez, Romel; Khan, Javed

    2013-01-01

    Peptide nucleic acids (PNAs) have gained much interest as molecular recognition tools in biology, medicine and chemistry. This is due to high hybridization efficiency to complimentary oligonucleotides and stability of the duplexes with RNA or DNA. We have synthesized 15/16-mer PNA probes to detect the HER2 mRNA. The performance of these probes to detect the HER2 target was evaluated by fluorescence imaging and fluorescence bead assays. The PNA probes have sufficiently discriminated between the wild type HER2 target and the mutant target with single base mismatches. Furthermore, the probes exhibited excellent linear concentration dependence between 0.4 to 400 fmol for the target gene. The results demonstrate potential application of PNAs as diagnostic probes with high specificity for quantitative measurements of amplifications or over-expressions of oncogenes. PMID:23593123

  13. Development of peptide nucleic acid probes for detection of the HER2 oncogene.

    Directory of Open Access Journals (Sweden)

    Belhu Metaferia

    Full Text Available Peptide nucleic acids (PNAs have gained much interest as molecular recognition tools in biology, medicine and chemistry. This is due to high hybridization efficiency to complimentary oligonucleotides and stability of the duplexes with RNA or DNA. We have synthesized 15/16-mer PNA probes to detect the HER2 mRNA. The performance of these probes to detect the HER2 target was evaluated by fluorescence imaging and fluorescence bead assays. The PNA probes have sufficiently discriminated between the wild type HER2 target and the mutant target with single base mismatches. Furthermore, the probes exhibited excellent linear concentration dependence between 0.4 to 400 fmol for the target gene. The results demonstrate potential application of PNAs as diagnostic probes with high specificity for quantitative measurements of amplifications or over-expressions of oncogenes.

  14. 灵芝粗多糖对二乙基亚硝胺诱导的小鼠肝脏组织形态及原癌基因和抑癌基因的影响%Effects ofGanoderma lucidum Crude Polysaccharide on Liver Tissue Morphology,and Expression of Proto-oncogene and Tumor Suppressor Gene mRNA, in Diethylnitrosamine-treated Mice

    Institute of Scientific and Technical Information of China (English)

    冯嫣; 王家东; 冯翠萍; 常明昌; 程红艳; 孟俊龙

    2014-01-01

    Sixty healthy,four week-old,mice were randomly divided into six groups (female∶male=1∶1 )as follows;normal control,diethylnitrosamine (DEN)model group,Ganoderma lucidum polysaccharide (GP) group,and low (DEN + 50 mg/kg·d),median (DEN+100 mg/kg·d)and high (DEN+200 mg/kg·d)GP dose groups.After 45 days,liver tissue morphology was observed using hematoxylin-eosin staining,and proto-oncogene (ras and H-myc)and tumor suppressor gene (p53 and Rb1)mRNA expression levels were determined using fluorescent quantitative real-time polymerase chain reaction (RT-PCR ). Our data demonstrated that GP had the protective function on liver cells of DEN-treated mice,and inhibited to a limited extent the occurrence or development of cancer by regulating the expression of proto-oncogenes and tumor suppressor genes.%采用苏木精-伊红染色法(hematoxylin-eosin staining )和实时荧光定量 PCR(real-time PCR,RT-PCR)法,研究灵芝(Ganoderma lucidum)粗多糖对二乙基亚硝胺(diethylnitrosamine,DEN)诱导的小鼠肝脏组织形态以及原癌基因H-ras和myc 和抑癌基因P53、Rb1 mRNA的影响,结果表明:灵芝粗多糖对 DEN 引起的小鼠肝脏损伤具有缓解作用,并可以抑制原癌基因的表达、提高抑癌基因的表达。

  15. REAL-TIME DETECTION OF SURVIVIN mRNA EXPRESSION IN CERVICAL CANCER CELL LINES USING MOLECULAR BEACON IMAGING

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    The initiated growth of human cancer cells of-ten mostly come fromthe abnor mal expression ofgenes.Survivinis anapotosis inhibitor of IAPfami-ly,cloned by Ambrosini in1997usingthe cDNAofeffector cell protease receptor-1(EPR-1),and is thekey gene for the development and advancement oftumor.Inthe present study,the feasibility of detec-ting the expression of survivin mRNA was exam-inedincervical cancer cell lines using molecular bea-coni maging technology.MATERIALS AND METHODS1Cervical cancer cell lines and ce...

  16. Single-Molecule Imaging of PSD-95 mRNA Translation in Dendrites and Its Dysregulation in a Mouse Model of Fragile X Syndrome.

    Science.gov (United States)

    Ifrim, Marius F; Williams, Kathryn R; Bassell, Gary J

    2015-05-06

    Fragile X syndrome (FXS) is caused by the loss of the fragile X mental retardation protein (FMRP), an RNA binding protein that regulates translation of numerous target mRNAs, some of which are dendritically localized. Our previous biochemical studies using synaptoneurosomes demonstrate a role for FMRP and miR-125a in regulating the translation of PSD-95 mRNA. However, the local translation of PSD-95 mRNA within dendrites and spines, as well as the roles of FMRP or miR-125a, have not been directly studied. Herein, local synthesis of a Venus-PSD-95 fusion protein was directly visualized in dendrites and spines using single-molecule imaging of a diffusion-restricted Venus-PSD-95 reporter under control of the PSD-95 3'UTR. The basal translation rates of Venus-PSD-95 mRNA was increased in cultured hippocampal neurons from Fmr1 KO mice compared with WT neurons, which correlated with a transient elevation of endogenous PSD-95 within dendrites. Following mGluR stimulation with (S)-3,5-dihydroxyphenylglycine, the rate of Venus-PSD-95 mRNA translation increased rapidly in dendrites of WT hippocampal neurons, but not in those of Fmr1 KO neurons or when the binding site of miR125a, previously shown to bind PSD-95 3'UTR, was mutated. This study provides direct support for the hypothesis that local translation within dendrites and spines is dysregulated in FXS. Impairments in the regulated local synthesis of PSD-95, a critical regulator of synaptic structure and function, may affect the spatiotemporal control of PSD-95 levels and affect dendritic spine development and synaptic plasticity in FXS. Copyright © 2015 the authors 0270-6474/15/357116-15$15.00/0.

  17. Targeting MET Amplification as a New Oncogenic Driver

    Energy Technology Data Exchange (ETDEWEB)

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

    2014-07-22

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

  18. Targeting MET Amplification as a New Oncogenic Driver

    Directory of Open Access Journals (Sweden)

    Hisato Kawakami

    2014-07-01

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

  19. Oncogenic cancer/testis antigens

    DEFF Research Database (Denmark)

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

    2015-01-01

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

  20. Multifunctional Fe3O4@Polydopamine Core–Shell Nanocomposites for Intracellular mRNA Detection and Imaging-Guided Photothermal Therapy

    Science.gov (United States)

    Lin, Li-Sen; Cong, Zhong-Xiao; Cao, Jian-Bo; Ke, Kai-Mei; Peng, Qiao-Li; Gao, Jinhao; Yang, Huang-Hao; Liu, Gang; Chen, Xiaoyuan

    2015-01-01

    Multifunctional nanocomposites have the potential to integrate sensing, diagnostic, and therapeutic functions into a single nanostructure. Herein, we synthesize Fe3O4@polydopamine core–shell nanocomposites (Fe3O4@PDA NCs) through an in situ self-polymerization method. Dopamine, a melanin-like mimic of mussel adhesive proteins, can self-polymerize to form surface-adherent polydopamine (PDA) films onto a wide range of materials including Fe3O4 nanoparticles used here. In such nanocomposites, PDA provides a number of advantages, such as near-infrared absorption, high fluorescence quenching efficiency, and a surface for further functionalization with biomolecules. We demonstrate the ability of the Fe3O4@PDA NCs to act as theranostic agents for intracellular mRNA detection and multimodal imaging-guided photothermal therapy. This work would stimulate interest in the use of PDA as a useful material to construct multifunctional nanocomposites for biomedical applications. PMID:24654734

  1. Multifunctional Fe₃O₄@polydopamine core-shell nanocomposites for intracellular mRNA detection and imaging-guided photothermal therapy.

    Science.gov (United States)

    Lin, Li-Sen; Cong, Zhong-Xiao; Cao, Jian-Bo; Ke, Kai-Mei; Peng, Qiao-Li; Gao, Jinhao; Yang, Huang-Hao; Liu, Gang; Chen, Xiaoyuan

    2014-04-22

    Multifunctional nanocomposites have the potential to integrate sensing, diagnostic, and therapeutic functions into a single nanostructure. Herein, we synthesize Fe3O4@polydopamine core-shell nanocomposites (Fe3O4@PDA NCs) through an in situ self-polymerization method. Dopamine, a melanin-like mimic of mussel adhesive proteins, can self-polymerize to form surface-adherent polydopamine (PDA) films onto a wide range of materials including Fe3O4 nanoparticles used here. In such nanocomposites, PDA provides a number of advantages, such as near-infrared absorption, high fluorescence quenching efficiency, and a surface for further functionalization with biomolecules. We demonstrate the ability of the Fe3O4@PDA NCs to act as theranostic agents for intracellular mRNA detection and multimodal imaging-guided photothermal therapy. This work would stimulate interest in the use of PDA as a useful material to construct multifunctional nanocomposites for biomedical applications.

  2. High-content image informatics of the structural nuclear protein NuMA parses trajectories for stem/progenitor cell lineages and oncogenic transformation.

    Science.gov (United States)

    Vega, Sebastián L; Liu, Er; Arvind, Varun; Bushman, Jared; Sung, Hak-Joon; Becker, Matthew L; Lelièvre, Sophie; Kohn, Joachim; Vidi, Pierre-Alexandre; Moghe, Prabhas V

    2017-02-01

    Stem and progenitor cells that exhibit significant regenerative potential and critical roles in cancer initiation and progression remain difficult to characterize. Cell fates are determined by reciprocal signaling between the cell microenvironment and the nucleus; hence parameters derived from nuclear remodeling are ideal candidates for stem/progenitor cell characterization. Here we applied high-content, single cell analysis of nuclear shape and organization to examine stem and progenitor cells destined to distinct differentiation endpoints, yet undistinguishable by conventional methods. Nuclear descriptors defined through image informatics classified mesenchymal stem cells poised to either adipogenic or osteogenic differentiation, and oligodendrocyte precursors isolated from different regions of the brain and destined to distinct astrocyte subtypes. Nuclear descriptors also revealed early changes in stem cells after chemical oncogenesis, allowing the identification of a class of cancer-mitigating biomaterials. To capture the metrology of nuclear changes, we developed a simple and quantitative "imaging-derived" parsing index, which reflects the dynamic evolution of the high-dimensional space of nuclear organizational features. A comparative analysis of parsing outcomes via either nuclear shape or textural metrics of the nuclear structural protein NuMA indicates the nuclear shape alone is a weak phenotypic predictor. In contrast, variations in the NuMA organization parsed emergent cell phenotypes and discerned emergent stages of stem cell transformation, supporting a prognosticating role for this protein in the outcomes of nuclear functions.

  3. Expression of bcl-2 oncogene in gastric precancerous lesions and its correlation with syndromes in traditional Chinese medicine

    Institute of Scientific and Technical Information of China (English)

    Ling Hu; Shao-Xian Lao; Chun-Zhi Tang

    2005-01-01

    AIM: To observe the protein and mRNA expression of bcl-2 oncogene in gastric precancerous lesions (GPL) and to analyze its correlation with syndromes in traditional Chinese medicine (TCM).METHODS: Sixty-seven patients with GPL confirmed by gastroscopy and pathology were studied, including 39 cases of moderate gastric mucosal dysplasia, 19 casesof severe gastric mucosa dysplasia, g cases of incompletecolon metaplasia. In syndrome differentiation of TCM, 17 cases belonged to the syndrome of qi and yin deficiency of the spleen and stomach complicated by qi stagnation, 21 cases belonged to the syndrome of qi and yin deficiency of the spleen and stomach complicated by stomach heat, 29 cases belonged to the syndrome of qi and yin deficiency of the spleen and stomach complicated by blood stasis. Protein and mRNA expression of bcl-2 oncogene weredetected by labeled streptavidin biotin (LSAB) immunohistochemistry and in situ hybridization respectively. RESULTS: Abnormal expression of protein and mRNA on bcl-2 oncogene was found in GPL, which increased gradually with the course of lesions. In moderate and severe gastric mucosal dysplasia and incomplete colon metaplasia, there was no difference in the expression of bcl-2 oncogene (P>0.05). In different accompanying syndromes, the expression of protein and mRNA on bcl-2 oncogene increased gradually in the following order: deficiency of both qi and yin of the spleen and stomach accompanying qi stagnation → stomach heat → blood stasis. In GPL, compared with accompanying blood stasis, there was an obvious difference in the expression of bd-2 oncogene between the syndrome of qi and yin deficiency of the spleen and stomach and accompanying stomach heat, so did accompanying qi stagnation (the level of protein: χ2 = 8.45, P<0.05; the level of mRNA: χ2 = 7.35,P<0.05).CONCLUSION: Apoptosis-associated bcl-2 oncogene is abnormally expressed in GPL, which correlates with different accompanying syndromes in TCM.

  4. Oncogenicity of human N-ras oncogene and proto-oncogene introduced into retroviral vectors

    Energy Technology Data Exchange (ETDEWEB)

    Souyri, M.; Vigon, I.; Charon, M.; Tambourin, P. (Hopital Cochin, Paris (France))

    1989-09-01

    The N-ras gene is the only member of the ras family which has never been naturally transduced into a retrovirus. In order to study the in vitro and in vivo oncogenicity of N-ras and to compare its pathogenicity to that of H-ras, the authors have inserted an activated or a normal form of human N-ras cDNA into a slightly modified Harvey murine sarcoma virus-derived vector in which the H-ras p21 coding region had been deleted. The resulting constructions were transfected into NIH 3T3 cells. The activated N-ras-containing construct (HSN) induced 10{sup 4} foci per {mu}g of DNA and was found to be as transforming as H-ras was. After infection of the transfected cells by either the ecotropic Moloney murine leukemia virus or the amphotropic 4070A helper viruses, rescued transforming viruses were injected into newborn mice. Both pseudotypes of HSN virus containing activated N-ras induced the typical Harvey disease with similar latency. However, they found that the virus which contained normal N-ras p21 (HSn) was also pathogenic and induced splenomegaly, lymphadenopathies, and sarcoma in mice after a latency of 3 to 7 weeks. In addition, Moloney murine leukemia virus pseudotypes of N-ras caused neurological disorders in 30% of the infected animals. These results differed markedly from those of previous experiments in which the authors had inserted the activated form of N-ras in the pSV(X) vector: the resulting SVN-ras virus was transforming on NIH 3T3 cells but was poorly oncogenic in vivo. Altogether, these data demonstrated unequivocally that N-ras is potentially as oncogenic as H-ras and that such oncogenic effect could depend on the vector environment.

  5. Oncogenic Brain Metazoan Parasite Infection

    Directory of Open Access Journals (Sweden)

    Angela N. Spurgeon

    2013-01-01

    Full Text Available Multiple observations suggest that certain parasitic infections can be oncogenic. Among these, neurocysticercosis is associated with increased risk for gliomas and hematologic malignancies. We report the case of a 71-year-old woman with colocalization of a metazoan parasite, possibly cysticercosis, and a WHO grade IV neuroepithelial tumor with exclusively neuronal differentiation by immunohistochemical stains (immunopositive for synaptophysin, neurofilament protein, and Neu-N and not for GFAP, vimentin, or S100. The colocalization and temporal relationship of these two entities suggest a causal relationship.

  6. Radiolabeled PNAs for imaging gene expression

    Energy Technology Data Exchange (ETDEWEB)

    Wickstrom, Eric; Sauter, Edward; Tian, Xianben; Rao, Sampath; Quin, Weyng; Thakur, Mathew [Thomas Jefferson Univ., PA (United States)

    2002-09-01

    Scintigraphic imaging of gene expression in vivo by non-invasive means could precisely direct physicians to appropriate intervention at the onset of disease and could contribute extensively to the management of patients. However no method is currently available to image specific over expressed oncogene mRNAs in vivo by scintigraphic imaging. Nevertheless, we have observed that Tc 99 m peptides can delineate tumors, and that PNA-peptides are specific for receptors on malignant cells and are taken up specifically and concentrated in nuclei. We hypothesize that antisense Tc 99 m PNA peptides will be taken up by human breast cancer cells, hybridize to complementary mRNA targets, and permit imaging of oncogene mRNAs in human breast cancer xenografts in a mouse model, providing a proof-of-principle for non-invasive detection of precancerous and invasive breast cancer. Oncogenes cyclin D1, erB-2, c-MYC and tumor suppressor p53 will be probed. If successful, this technique will be useful for diagnostic imaging of other solid tumors as well. (author)

  7. Comparative study of ¹⁸F-FDG-PET/CT imaging and serum hTERT mRNA quantification in cancer diagnosis.

    Science.gov (United States)

    Ping, Bingqiong; Tsuno, Satoshi; Wang, Xinhui; Ishihara, Yoshitaka; Yamashita, Taro; Miura, Keigo; Miyoshi, Fuminori; Shinohara, Yuki; Matsuki, Tsutomu; Tanabe, Yoshio; Tanaka, Noriaki; Ogawa, Toshihide; Shiota, Goshi; Miura, Norimasa

    2015-10-01

    We have reported on the clinical usefulness of human telomerase reverse transcriptase (hTERT) mRNA quantification in sera in patients with several cancers. Positron emission tomography-computed tomography (PET/CT) using ¹⁸F-fluorodeoxyglucose (FDG) has recently become an excellent modality for detecting cancer. We performed a diagnostic comparative study of FDG-PET/CT and hTERT mRNA quantification in patients with cancer. Four hundred seventy subjects, including 125 healthy individuals and 345 outpatients with cancer who had received medical treatments for cancer in their own or other hospitals, were enrolled. The subjects were diagnosed by FDG-PET/CT, and we measured their serum hTERT mRNA levels using real-time RT-PCR, correlating the quantified values with the clinical course. In this prospective study, we statistically assessed the sensitivity and specificity, and their clinical significance. hTERT mRNA and FDG-PET/CT were demonstrated to be correlated with the clinical parameters of metastasis and recurrence (P cancer compared with noncancer patients, respectively. A multivariate analysis showed a significant difference in the detection by FDG-PET/CT, ¹⁸F-FDG uptake, the detection by hTERT mRNA, and age. The use of both FDG-PET/CT and hTERT mRNA resulted in a positivity of 94.4% (221/234) for the detection of viable tumor cells. FDG-PET/CT is superior to hTERT mRNA quantification in the early detection of cancer and combinative use of FDG-PET/CT and hTERT mRNA may improve the diagnostic accuracy of cancer.

  8. 40 CFR 798.3300 - Oncogenicity.

    Science.gov (United States)

    2010-07-01

    ... Species of Experimental Animals for Inhalation Carcinogenicity Studies” Paper presented at Conference on...) HEALTH EFFECTS TESTING GUIDELINES Chronic Exposure § 798.3300 Oncogenicity. (a) Purpose. The objective of a long-term oncogenicity study is to observe test animals for a major portion of their life span for...

  9. Polymorphic changes of cell phenotype caused by elevated expression of an exogenous NEU proto-oncogene.

    Science.gov (United States)

    Tarakhovsky, A M; Resnikov, M; Zaichuk, T; Tugusheva, M V; Butenko, Z A; Prassolov, V S

    1990-03-01

    The NEU proto-oncogene encodes a 185,000 dalton transmembrane glycoprotein with extensive homology to epidermal growth factor receptor. In the current study the effect of exogenous NEU expression on phenotype and growth properties of cells established lines was examined. The replication defective retroviruses were used to express constitutively NEU cDNA in the Rat-1, NIH3T3 and Balb/c3T3 cells. In spite of the practically similar NEU mRNA and protein content in infected cells only in Balb/c3T3 cells, high NEU expression ultimately led to oncogenic transformation. The Rat-1 cells were practically insensitive to oncogenic action of NEU. Subpopulation divergency with respect to NEU-dependent transformation was also revealed in infected NIH3T3 cells. These results suggest the existence of unknown host-specific factor(s) determining the response of cells to NEU overexpression.

  10. Oncogenic osteomalacia presenting as bilateral stress fractures of the tibia

    Energy Technology Data Exchange (ETDEWEB)

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

    1999-01-01

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

  11. Single nucleotide polymorphisms in microRNA binding sites of oncogenes: implications in cancer and pharmacogenomics.

    Science.gov (United States)

    Manikandan, Mayakannan; Munirajan, Arasambattu Kannan

    2014-02-01

    Cancer, a complex genetic disease involving uncontrolled cell proliferation, is caused by inactivation of tumor suppressor genes and activation of oncogenes. A vast majority of these cancer causing genes are known targets of microRNAs (miRNAs) that bind to complementary sequences in 3' untranslated regions (UTR) of messenger RNAs and repress them from translation. Single Nucleotide Polymorphisms (SNPs) occurring naturally in such miRNA binding regions can alter the miRNA:mRNA interaction and can significantly affect gene expression. We hypothesized that 3'UTR SNPs in miRNA binding sites of proto-oncogenes could abrogate their post-transcriptional regulation, resulting in overexpression of oncogenic proteins, tumor initiation, progression, and modulation of drug response in cancer patients. Therefore, we developed a systematic computational pipeline that integrates data from well-established databases, followed stringent selection criteria and identified a panel of 30 high-confidence SNPs that may impair miRNA target sites in the 3' UTR of 54 mRNA transcripts of 24 proto-oncogenes. Further, 8 SNPs amidst them had the potential to determine therapeutic outcome in cancer patients. Functional annotation suggested that altogether these SNPs occur in proto-oncogenes enriched for kinase activities. We provide detailed in silico evidence for the functional effect of these candidate SNPs in various types of cancer.

  12. Proto-oncogenes expression in the process of asthma airway remodeling

    Institute of Scientific and Technical Information of China (English)

    LIU Ying-ge; QI Hao-wen; LI Huan-zhang

    2002-01-01

    Objective: To observe the expression of proto-oncogenes in the process of airway remodeling in asthma. Methods: Guinea pig was used as an asthma model challenged by ovoglobulin. Dot-blot, Northernblot molecular hybridization and immunohistochemistry techniques were used to detect the expression of cfos, c-myc, c-jun and c-sis. Results: Expression of c-fos and c-myc mRNA could not be detected or detected at very low level in the control group. There were greatly increased expression of c-fos and c-nyc mRNA after guinea pigs were challenged by ovoglobulin. Thirty minutes after the challenge, the expression of c-fos and c-myc mRNA reached to the peak and returned to normal level 4 h after the challenge. Immunohistochemistry studies showed that Fos, Myc, Jun and Sis expressed at low level in control group and increased after ovoglobulin stimulation. Immunohistochemically positive cells laid in the plasma of airway epithelium,in cell nucleus of bronchial epithelium and in the inflammatory cells. Pathologic studies showed there were smooth muscle thicken around bronchia and lymphocytes infiltration under mucosa or around bronchia smooth muscle. Conclusion: Proto-oncogenes expressed in airway of asthma in a guinea pig model, proto-oncogenes may have roles in the process of airway remodeling.

  13. A novel putative tyrosine kinase receptor with oncogenic potential.

    Science.gov (United States)

    Janssen, J W; Schulz, A S; Steenvoorden, A C; Schmidberger, M; Strehl, S; Ambros, P F; Bartram, C R

    1991-11-01

    We have detected transforming activity by a tumorigenicity assay using NIH3T3 cells transfected with DNA from a chronic myeloproliferative disorder patient. Here, we report the cDNA cloning of the corresponding oncogene, designated UFO, in allusion to the as yet unidentified function of its protein. Nucleotide sequence analysis of a 3116bp cDNA clone revealed a 2682-bp-long open reading frame capable of directing the synthesis of a 894 amino acid polypeptide. The predicted UFO protein exhibits characteristic features of a transmembrane receptor with associated tyrosine kinase activity. The UFO proto-oncogene maps to human chromosome 19q13.1 and is transcribed into two 5.0 kb and 3.2 kb mRNAs in human bone marrow and human tumor cell lines. The UFO locus is evolutionarily conserved between vertebrate species. A 4.0 kb mRNA of the murine UFO homolog is expressed in a variety of different mouse tissues. We thus have identified a novel element of the complex signaling network involved in the control of cell proliferation and differentiation.

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2011-09-15

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

  15. Amplification of cellular oncogenes in solid tumors

    Directory of Open Access Journals (Sweden)

    Ozkan Bagci

    2015-01-01

    Full Text Available The term gene amplification refers to an increase in copy number of a gene. Upregulation of gene expression through amplification is a general mechanism to increase gene dosage. Oncogene amplifications have been shown in solid human cancers and they are often associated with progression of cancer. Defining oncogene amplification is useful since it is used as a prognostic marker in clinical oncology nowadays, especially v-erb-b2 avian erythroblastic leukemia viral oncogene homolog 2 (HER2 targeted agents are used in breast cancer patients with high level of HER2 overexpression as a therapeutic approach. However, patients without HER2 overexpression do not appear to benefit from these agents. We concluded that determination of oncogene amplification in solid tumors is an important factor in treatment of human cancers with many unknowns. We have referred to PubMed and some databases to prepare this article.

  16. Oncogenic c-kit transcript is a target for binase.

    Science.gov (United States)

    Mitkevich, Vladimir A; Petrushanko, Irina Y; Kretova, Olga V; Zelenikhin, Pavel V; Prassolov, Vladimir S; Tchurikov, Nickolai A; Ilinskaya, Olga N; Makarov, Alexander A

    2010-07-01

    Mutational activation of c-Kit receptor tyrosine kinase is common in acute myelogenous leukemia (AML). One such activating point mutation is the N822K replacement in the c-Kit protein. Here we investigate the selective cytotoxic effect of binase--RNase from Bacillus intermedius--on FDC-P1-N822K cells. These cells were derived from myeloid progenitor FDC-P1 cells, in which ectopic expression of N822K c-kit gene induces interleukin-3 independent growth. In order to determine whether the sensitivity of these cells to binase is caused by the expression of c-kit oncogene, the cytotoxicity of the RNase was studied in the presence of selective inhibitor of mutated c-Kit imatinib (Gleevec). Inhibition of mutated c-Kit protein leads to the loss of cell sensitivity to the apoptotic effect of binase, while the latter still decreases the amount of cellular RNA. Using green fluorescent protein as an expression marker for the c-Kit oncoprotein, we demonstrate that the elimination of c-Kit is the key factor in selective cytotoxicity of binase. Quantitative RT-PCR with RNA samples isolated from the binase-treated FDC-P1-N822K cells shows that binase treatment results in 41% reduction in the amount of с-kit mRNA. This indicates that the transcript of the activated mutant c-kit is the target for toxic action of binase. Thus, the combination of inhibition of oncogenic protein with the destruction of its mRNA is a promising approach to eliminating malignant cells.

  17. IMP3 RNP safe houses prevent miRNA-directed HMGA2 mRNA decay in cancer and development

    DEFF Research Database (Denmark)

    Jønson, Lars; Christiansen, Jan; Hansen, Thomas van Overeem;

    2014-01-01

    The IMP3 RNA-binding protein is associated with metastasis and poor outcome in human cancer. Using solid cancer transcriptome data, we found that IMP3 correlates with HMGA2 mRNA expression. Cytoplasmic IMP3 granules contain HMGA2, and IMP3 dose-dependently increases HMGA2 mRNA. HMGA2 is regulated...... that IMP3 RNPs may function as cytoplasmic safe houses and prevent miRNA-directed mRNA decay of oncogenes during tumor progression....

  18. Expressions of estrogen receptor subtypes and c-met proto-oncogene in endometrial carcinoma and their correlation

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    Objective To investigate the expressions of estrogen receptor(ER)subtypes and c-met proto-oncogene in human endometrial carcinomas and to assess the clinical significance of ER and c-met in this carcinoma.Methods Reverse transcription PCR(RT-PCR)was used to detect the expressions of ERα,ERβ and c-met proto-oncogene mRNA in 30 samples of endometrial carcinoma and 11 samples of normal endometrium.Results The expression of ERα in endometrial carcinoma(0.70±0.40)was significantly reduced in comparison to that i...

  19. Effect of energy restriction and physical exercise intervention on phenotypic flexibility as examined by transcriptomics analyses of mRNA from adipose tissue and whole body magnetic resonance imaging.

    Science.gov (United States)

    Lee, Sindre; Norheim, Frode; Langleite, Torgrim M; Noreng, Hans J; Storås, Trygve H; Afman, Lydia A; Frost, Gary; Bell, Jimmy D; Thomas, E Louise; Kolnes, Kristoffer J; Tangen, Daniel S; Stadheim, Hans K; Gilfillan, Gregor D; Gulseth, Hanne L; Birkeland, Kåre I; Jensen, Jørgen; Drevon, Christian A; Holen, Torgeir

    2016-11-01

    Overweight and obesity lead to changes in adipose tissue such as inflammation and reduced insulin sensitivity. The aim of this study was to assess how altered energy balance by reduced food intake or enhanced physical activity affect these processes. We studied sedentary subjects with overweight/obesity in two intervention studies, each lasting 12 weeks affecting energy balance either by energy restriction (~20% reduced intake of energy from food) in one group, or by enhanced energy expenditure due to physical exercise (combined endurance- and strength-training) in the other group. We monitored mRNA expression by microarray and mRNA sequencing from adipose tissue biopsies. We also measured several plasma parameters as well as fat distribution with magnetic resonance imaging and spectroscopy. Comparison of microarray and mRNA sequencing showed strong correlations, which were also confirmed using RT-PCR In the energy restricted subjects (body weight reduced by 5% during a 12 weeks intervention), there were clear signs of enhanced lipolysis as monitored by mRNA in adipose tissue as well as plasma concentration of free-fatty acids. This increase was strongly related to increased expression of markers for M1-like macrophages in adipose tissue. In the exercising subjects (glucose infusion rate increased by 29% during a 12-week intervention), there was a marked reduction in the expression of markers of M2-like macrophages and T cells, suggesting that physical exercise was especially important for reducing inflammation in adipose tissue with insignificant reduction in total body weight. Our data indicate that energy restriction and physical exercise affect energy-related pathways as well as inflammatory processes in different ways, probably related to macrophages in adipose tissue.

  20. Human genome: proto-oncogenes and proretroviruses.

    Science.gov (United States)

    Kisselev, L L; Chumakov, I M; Zabarovsky, E R; Prassolov, V S; Mett, V L; Berditchevsky, F B; Tret'yakov, L D

    1985-01-01

    A brief review of the studies undertaken at the Laboratory for Molecular Bases of Oncogenesis (Institute of Molecular Biology, Moscow) till middle of 1984 is presented. The human genome contains multiple dispersed nucleotide sequences related to the proto-oncogene mos and to proretroviral sequences in tight juxtaposition to each other. From sequencing appropriate cloned fragments of human DNA in phage and plasmid vectors it follows that one of these regions, NV-1, is a pseudogene of proto-mos with partial duplications and two Alu elements intervening its coding sequence, and the other, CL-1, seems to be also a mos-related gene with a deletion of the internal part of the structural gene. CL-1 is flanked by a proretroviral-like sequence including tRNAiMet binding site and U5 (part of the long terminal repeat). The proretroviral-like sequences are transcribed in 21-35S poly(A)+RNA abundant in normal and malignant human cells. Two hypotheses are proposed: endogenous retroviruses take part in amplification of at least some proto-oncogenes; proto-oncogenes are inactivated via insertion of movable genetic elements and conversion into pseudogenes. Potential oncogenicity of a normal human genome undergoes two controversial influences: it increases due to proto-oncogene amplification and decreases due to inactivation of some of them.

  1. RECQL4 helicase has oncogenic potential in sporadic breast cancers.

    Science.gov (United States)

    Arora, Arvind; Agarwal, Devika; Abdel-Fatah, Tarek Ma; Lu, Huiming; Croteau, Deborah L; Moseley, Paul; Aleskandarany, Mohammed A; Green, Andrew R; Ball, Graham; Rakha, Emad A; Chan, Stephen Yt; Ellis, Ian O; Wang, Lisa L; Zhao, Yongliang; Balajee, Adayabalam S; Bohr, Vilhelm A; Madhusudan, Srinivasan

    2016-03-01

    RECQL4 helicase is a molecular motor that unwinds DNA, a process essential during DNA replication and DNA repair. Germ-line mutations in RECQL4 cause type II Rothmund-Thomson syndrome (RTS), characterized by a premature ageing phenotype and cancer predisposition. RECQL4 is widely considered to be a tumour suppressor, although its role in human breast cancer is largely unknown. As the RECQL4 gene is localized to chromosome 8q24, a site frequently amplified in sporadic breast cancers, we hypothesized that it may play an oncogenic role in breast tumourigenesis. To address this, we analysed large cohorts for gene copy number changes (n = 1977), mRNA expression (n = 1977) and protein level (n = 1902). Breast cancer incidence was also explored in 58 patients with type II RTS. DNA replication dynamics and chemosensitivity was evaluated in RECQL4-depleted breast cancer cells in vitro. Amplification or gain in gene copy number (30.6%), high-level mRNA expression (51%) and high levels of protein (23%) significantly associated with aggressive tumour behaviour, including lymph node positivity, larger tumour size, HER2 overexpression, ER-negativity, triple-negative phenotypes and poor survival. RECQL4 depletion impaired the DNA replication rate and increased chemosensitivity in cultured breast cancer cells. Thus, although recognized as a 'safe guardian of the genome', our data provide compelling evidence that RECQL4 is tumour promoting in established breast cancers. Copyright © 2015 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.

  2. Somatic Copy Number Alterations at Oncogenic Loci Show Diverse Correlations with Gene Expression

    Science.gov (United States)

    Roszik, Jason; Wu, Chang-Jiun; Siroy, Alan E.; Lazar, Alexander J.; Davies, Michael A.; Woodman, Scott E.; Kwong, Lawrence N.

    2016-01-01

    Somatic copy number alterations (SCNAs) affecting oncogenic drivers have a firmly established role in promoting cancer. However, no agreed-upon standard exists for calling locus-specific amplifications and deletions in each patient sample. Here, we report the correlative analysis of copy number amplitude and length with gene expression across 6,109 samples from The Cancer Genome Atlas (TCGA) dataset across 16 cancer types. Using specificity, sensitivity, and precision-based scores, we assigned optimized amplitude and length cutoffs for nine recurrent SCNAs affecting known oncogenic drivers, using mRNA expression as a functional readout. These cutoffs captured the majority of SCNA-driven, highly-expression-altered samples. The majority of oncogenes required only amplitude cutoffs, as high amplitude samples were almost invariably focal; however, CDKN2A and PTEN uniquely required both amplitude and length cutoffs as primary predictors. For PTEN, these extended to downstream AKT activation. In contrast, SCNA genes located peri-telomerically or in fragile sites showed poor expression-copy number correlations. Overall, our analyses identify optimized amplitude and length cutoffs as efficient predictors of gene expression changes for specific oncogenic SCNAs, yet warn against one-size-fits-all interpretations across all loci. Our results have implications for cancer data analyses and the clinic, where copy number and mutation data are increasingly used to personalize cancer therapy.

  3. Oncogenic human papillomaviruses activate the tumor-associated lens epithelial-derived growth factor (LEDGF gene.

    Directory of Open Access Journals (Sweden)

    Jenny Leitz

    2014-03-01

    Full Text Available The expression of the human papillomavirus (HPV E6/E7 oncogenes is crucial for HPV-induced malignant cell transformation. The identification of cellular targets attacked by the HPV oncogenes is critical for our understanding of the molecular mechanisms of HPV-associated carcinogenesis and may open novel therapeutic opportunities. Here, we identify the Lens Epithelial-Derived Growth Factor (LEDGF gene as a novel cellular target gene for the HPV oncogenes. Elevated LEDGF expression has been recently linked to human carcinogenesis and can protect tumor cells towards different forms of cellular stress. We show that intracellular LEDGF mRNA and protein levels in HPV-positive cancer cells are critically dependent on the maintenance of viral oncogene expression. Ectopic E6/E7 expression stimulates LEDGF transcription in primary keratinocytes, at least in part via activation of the LEDGF promoter. Repression of endogenous LEDGF expression by RNA interference results in an increased sensitivity of HPV-positive cancer cells towards genotoxic agents. Immunohistochemical analyses of cervical tissue specimens reveal a highly significant increase of LEDGF protein levels in HPV-positive lesions compared to histologically normal cervical epithelium. Taken together, these results indicate that the E6/E7-dependent maintenance of intracellular LEDGF expression is critical for protecting HPV-positive cancer cells against various forms of cellular stress, including DNA damage. This could support tumor cell survival and contribute to the therapeutic resistance of cervical cancers towards genotoxic treatment strategies in the clinic.

  4. Oncogenic Human Papillomaviruses Activate the Tumor-Associated Lens Epithelial-Derived Growth Factor (LEDGF) Gene

    Science.gov (United States)

    Leitz, Jenny; Reuschenbach, Miriam; Lohrey, Claudia; Honegger, Anja; Accardi, Rosita; Tommasino, Massimo; Llano, Manuel; von Knebel Doeberitz, Magnus; Hoppe-Seyler, Karin; Hoppe-Seyler, Felix

    2014-01-01

    The expression of the human papillomavirus (HPV) E6/E7 oncogenes is crucial for HPV-induced malignant cell transformation. The identification of cellular targets attacked by the HPV oncogenes is critical for our understanding of the molecular mechanisms of HPV-associated carcinogenesis and may open novel therapeutic opportunities. Here, we identify the Lens Epithelial-Derived Growth Factor (LEDGF) gene as a novel cellular target gene for the HPV oncogenes. Elevated LEDGF expression has been recently linked to human carcinogenesis and can protect tumor cells towards different forms of cellular stress. We show that intracellular LEDGF mRNA and protein levels in HPV-positive cancer cells are critically dependent on the maintenance of viral oncogene expression. Ectopic E6/E7 expression stimulates LEDGF transcription in primary keratinocytes, at least in part via activation of the LEDGF promoter. Repression of endogenous LEDGF expression by RNA interference results in an increased sensitivity of HPV-positive cancer cells towards genotoxic agents. Immunohistochemical analyses of cervical tissue specimens reveal a highly significant increase of LEDGF protein levels in HPV-positive lesions compared to histologically normal cervical epithelium. Taken together, these results indicate that the E6/E7-dependent maintenance of intracellular LEDGF expression is critical for protecting HPV-positive cancer cells against various forms of cellular stress, including DNA damage. This could support tumor cell survival and contribute to the therapeutic resistance of cervical cancers towards genotoxic treatment strategies in the clinic. PMID:24604027

  5. Oncogenic human papillomaviruses activate the tumor-associated lens epithelial-derived growth factor (LEDGF) gene.

    Science.gov (United States)

    Leitz, Jenny; Reuschenbach, Miriam; Lohrey, Claudia; Honegger, Anja; Accardi, Rosita; Tommasino, Massimo; Llano, Manuel; von Knebel Doeberitz, Magnus; Hoppe-Seyler, Karin; Hoppe-Seyler, Felix

    2014-03-01

    The expression of the human papillomavirus (HPV) E6/E7 oncogenes is crucial for HPV-induced malignant cell transformation. The identification of cellular targets attacked by the HPV oncogenes is critical for our understanding of the molecular mechanisms of HPV-associated carcinogenesis and may open novel therapeutic opportunities. Here, we identify the Lens Epithelial-Derived Growth Factor (LEDGF) gene as a novel cellular target gene for the HPV oncogenes. Elevated LEDGF expression has been recently linked to human carcinogenesis and can protect tumor cells towards different forms of cellular stress. We show that intracellular LEDGF mRNA and protein levels in HPV-positive cancer cells are critically dependent on the maintenance of viral oncogene expression. Ectopic E6/E7 expression stimulates LEDGF transcription in primary keratinocytes, at least in part via activation of the LEDGF promoter. Repression of endogenous LEDGF expression by RNA interference results in an increased sensitivity of HPV-positive cancer cells towards genotoxic agents. Immunohistochemical analyses of cervical tissue specimens reveal a highly significant increase of LEDGF protein levels in HPV-positive lesions compared to histologically normal cervical epithelium. Taken together, these results indicate that the E6/E7-dependent maintenance of intracellular LEDGF expression is critical for protecting HPV-positive cancer cells against various forms of cellular stress, including DNA damage. This could support tumor cell survival and contribute to the therapeutic resistance of cervical cancers towards genotoxic treatment strategies in the clinic.

  6. Highly Selective Targeting of Hepatic Stellate Cells for Liver Fibrosis Treatment Using a d-Enantiomeric Peptide Ligand of Fn14 Identified by Mirror-Image mRNA Display.

    Science.gov (United States)

    Huang, Luying; Xie, Jing; Bi, Qiuyan; Li, Zhuoxuan; Liu, Sha; Shen, Qing; Li, Chong

    2017-05-01

    Although liver fibrosis is a major public health issue, there is still no effective drug therapy in the clinic. Fibroblast growth factor-inducible 14 (Fn14), a membrane receptor highly specifically expressed in activated hepatic stellate cells (HSCs), is the key driver of liver fibrosis, and thus, it has a great potential as a novel target for the development of effective treatment. Here, we identified a d-enantiomeric peptide ligand of Fn14 through mirror-image mRNA display. This included the chemical synthesis of a d-enantiomer of the target protein (extracellular domain of Fn14), identification of an l-peptide ligand of d-Fn14 using a constructed mRNA peptide library, and identification of a d-enantiomer of the l-peptide, which is a ligand of the natural Fn14 for reasons of symmetry. The obtained d-peptide ligand showed strong binding to Fn14 while maintaining high proteolytic resistance. As a targeting moiety, this d-peptide successfully mediated high selectivity of activated HSCs for liposomal vehicles compared to that of other major cell types in the liver and significantly enhanced the accumulation of liposomes in the liver fibrosis region of a carbon tetrachloride-induced mouse model. Moreover, in combination with curcumin as an encapsulated load, a liposomal formulation conjugated with this d-peptide showed powerful inhibition of the proliferation of activated HSCs and reduced the liver fibrosis to a significant extent in vivo. This Fn14-targeting strategy may represent a promising approach to targeted drug delivery for liver fibrosis treatment. Meanwhile, the mirror-image mRNA display can provide a new arsenal for the development of d-peptide-based therapeutics against a variety of human diseases.

  7. HUMAN PAPILLOMA VIRUS — ONCOGENIC VIRUS

    Directory of Open Access Journals (Sweden)

    A.N. Mayansky

    2010-01-01

    Full Text Available The lecture is devoted to oncogenic viruses, particularly human papilloma virus. Papilloma viral infection is found in all parts of the globe and highly contagious. In addition to exhaustive current data on classification, specifics of papilloma viruses composition and epidemiology, the author describes in great detail the malignization mechanisms of papilloma viruses pockets. Also, issues of diagnostics and specific prevention and treatment of diseases caused by this virus are illustrated. Key words: oncogenic viruses, papilloma viruses, prevention, vaccination. (Pediatric Pharmacology. – 2010; 7(4:48-55

  8. Chemically robust fluoroalkyl phthalocyanine-oligonucleotide bioconjugates and their GRP78 oncogene photocleavage activity.

    Science.gov (United States)

    Patel, Pradeepkumar; Patel, Hemantbhai H; Borland, Emily; Gorun, Sergiu M; Sabatino, David

    2014-06-18

    The first representative of functionalized fluoroalkyl phthalocyanines, F48H7(COOH)PcZn, is reported. The complex generates (1)O2 affording long-lasting photooxidation of an external substrate without self-decomposition. The carboxylic group couples with an antisense oligonucleotide targeting GRP78 oncogenes, resulting in the F48H7PcZn-cancer targeting oligonucleotide (CTO). The bioconjugated fluorophthalocyanine effectively hybridizes complementary GRP78 DNA and mRNA sequences. Piperidine cleavage assays reveal desired photochemical oligonucleotide oxidative degradation for both F48H7PcZn-CTO:DNA and F48H7PcZn-CTO:mRNA hybrids. This new materials strategy could be extended to other functional fluorinated phthalocyanines-antisense oligonucleotide combinations for long-lasting oncogene-targeting photodynamic therapy.

  9. Oncogene v-jun modulates DNA replication.

    Science.gov (United States)

    Wasylyk, C; Schneikert, J; Wasylyk, B

    1990-07-01

    Cell transformation leads to alterations in both transcription and DNA replication. Activation of transcription by the expression of a number of transforming oncogenes is mediated by the transcription factor AP1 (Herrlich & Ponta, 1989; Imler & Wasylyk, 1989). AP1 is a composite transcription factor, consisting of members of the jun and fos gene-families. c-jun and c-fos are progenitors of oncogenes, suggestion that an important transcriptional event in cell transformation is altered activity of AP1, which may arise either indirectly by oncogene expression or directly by structural modification of AP1. We report here that the v-jun oncogene and its progenitor c-jun, as fusion proteins with the lex-A-repressor DNA binding domain, can activate DNA replication from the Polyoma virus (Py) origin of replication, linked to the lex-A operator. The transcription-activation region of v-jun is required for activation of replication. When excess v-jun is expressed in the cell, replication is inhibited or 'squelched'. These results suggest that one consequence of deregulated jun activity could be altered DNA replication and that there are similarities in the way v-jun activates replication and transcription.

  10. Oncogene mutational profile in nasopharyngeal carcinoma

    Directory of Open Access Journals (Sweden)

    Zhang ZC

    2014-03-01

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

  11. Multiple oncogenic mutations related to targeted therapy in nasopharyngeal carcinoma

    Institute of Scientific and Technical Information of China (English)

    Jian-Wei Zhang; Hong-Yuan Zhao; Yu-Xiang Ma; Zhi-Huang Hu; Pei-Yu Huang; Li Zhang; Tao Qin; Shao-Dong Hong; Jing Zhang; Wen-Feng Fang; Yuan-Yuan Zhao; Yun-Peng Yang; Cong Xue; Yan Huang

    2015-01-01

    Introduction:An increasing number of targeted drugs have been tested for the treatment of nasopharyngeal carcinoma (NPC). However, targeted therapy-related oncogenic mutations have not been fully evaluated. This study aimed to detect targeted therapy-related oncogenic mutations in NPC and to determine which targeted therapy might be potentially effective in treating NPC. Methods:By using the SNaPshot assay, a rapid detection method, 19 mutation hotspots in 6 targeted therapy-related oncogenes were examined in 70 NPC patients. The associations between oncogenic mutations and clinicopathologic factors were analyzed. Results:Among 70 patients, 12 (17.1%) had mutations in 5 oncogenes:7 (10.0%) had v-kit Hardy-Zuckerman 4 feline sarcoma viral oncogene homolog (KIT) mutation, 2 (2.8%) had epidermal growth factor receptor (EGFR) mutation, 1 (1.4%) had phosphatidylinositol-4,5-bisphosphate 3-kinase, catalytic subunit alpha (PIK3CA) mutation, 1 (1.4%) had Kirsten rat sarcoma viral oncogene homolog (KRAS) mutation, and 1 (1.4%) had simultaneous EGFR and v-Raf murine sarcoma viral oncogene homolog B1 (BRAF) mutations. No significant differences were observed between oncogenic mutations and clinicopathologic characteristics. Additionally, these oncogenic mutations were not associated with tumor recurrence and metastasis. Conclusions:Oncogenic mutations are present in NPC patients. The efficacy of targeted drugs on patients with the related oncogenic mutations requires further validation.

  12. A "liaison dangereuse" between AUF1/hnRNPD and the oncogenic tyrosine kinase NPM-ALK.

    Science.gov (United States)

    Fawal, Mohamad; Armstrong, Florence; Ollier, Severine; Dupont, Henri; Touriol, Christian; Monsarrat, Bernard; Delsol, Georges; Payrastre, Bernard; Morello, Dominique

    2006-10-15

    Nucleophosmin-anaplastic lymphoma kinase (NPM-ALK) is a chimeric protein expressed in a subset of cases of anaplastic large cell lymphoma (ALCL) for which constitutive expression represents a key oncogenic event. The ALK signaling pathway is complex and probably involves functional redundancy between various signaling substrates of ALK. Despite numerous studies on signaling mediators, the molecular mechanisms contributing to the distinct oncogenic features of NPM-ALK remain incompletely understood. The search for additional interacting partners of NPM-ALK led to the discovery of AUF1/hnRNPD, a protein implicated in AU-rich element (ARE)-directed mRNA decay. AUF1 was immunoprecipitated with ALK both in ALCL-derived cells and in NIH3T3 cells stably expressing NPM-ALK or other X-ALK fusion proteins. AUF1 and NPM-ALK were found concentrated in the same cytoplasmic foci, whose formation required NPM-ALK tyrosine kinase activity. AUF1 was phosphorylated by ALK in vitro and was hyperphosphorylated in NPM-ALK-expressing cells. Its hyperphosphorylation was correlated with increased stability of several AUF1 target mRNAs encoding key regulators of cell proliferation and with increased cell survival after transcriptional arrest. Thus, AUF1 could function in a novel pathway mediating the oncogenic effects of NPM-ALK. Our data establish an important link between oncogenic kinases and mRNA turnover, which could constitute a critical aspect of tumorigenesis.

  13. Functional Genomic mRNA Profiling of Colorectal Adenomas : Identification and in vivo Validation of CD44 and Splice Variant CD44v6 as Molecular Imaging Targets

    NARCIS (Netherlands)

    Hartmans, Elmire; Orian-Rousseau, Veronique; Matzke-Ogi, Alexandra; Karrenbeld, Arend; de Groot, Derk Jan A.; de Jong, Steven; van Dam, Gooitzen M.; Fehrmann, Rudolf S. N.; Nagengast, Wouter B.

    2017-01-01

    Colorectal cancer (CRC) is the third leading cause of cancer-related deaths worldwide. High adenoma miss rates, especially seen in high-risk patients, demand for better endoscopic detection. By fluorescently 'highlighting' specific molecular characteristics, endoscopic molecular imaging has great

  14. Oncogenic kinase NPM/ALK induces expression of HIF1a mRNA

    DEFF Research Database (Denmark)

    Marzec, M; Liu, X; Wong, W;

    2011-01-01

    to the HIF1a gene promoter as shown by the chromatin immunoprecipitation assay and is required for HIF1a gene expression as demonstrated by its small interfering RNA-mediated depletion. In turn, depletion of HIF1a increases mammalian target of rapamycin complex 1 activation, cell growth and proliferation...

  15. Metastatic pancreatic cancer is dependent on oncogenic Kras in mice.

    Directory of Open Access Journals (Sweden)

    Meredith A Collins

    Full Text Available Pancreatic cancer is one of the deadliest human malignancies, and its prognosis has not improved over the past 40 years. Mouse models that spontaneously develop pancreatic adenocarcinoma and mimic the progression of the human disease are emerging as a new tool to investigate the basic biology of this disease and identify potential therapeutic targets. Here, we describe a new model of metastatic pancreatic adenocarcinoma based on pancreas-specific, inducible and reversible expression of an oncogenic form of Kras, together with pancreas-specific expression of a mutant form of the tumor suppressor p53. Using high-resolution magnetic resonance imaging to follow individual animals in longitudinal studies, we show that both primary and metastatic lesions depend on continuous Kras activity for their maintenance. However, re-activation of Kras* following prolonged inactivation leads to rapid tumor relapse, raising the concern that Kras*-resistance might eventually be acquired. Thus, our data identifies Kras* as a key oncogene in pancreatic cancer maintenance, but raises the possibility of acquired resistance should Kras inhibitors become available for use in pancreatic cancer.

  16. Comparison of Whole Body Diffusion Weighted Magnetic Resonance Imaging and Somatostatin Receptor Scintigraphy for Oncogenic Osteomalacia%全身磁共振弥散加权成像与生长抑素受体显像在瘤源性骨质软化症的应用比较

    Institute of Scientific and Technical Information of China (English)

    李烁; 薛华丹; 姜艳; 夏维波; 景红丽; 陈黎波; 孙非; 金征宇

    2012-01-01

    目的 比较全身磁共振弥散加权成像(WB-DWI)和生长抑素受体显像(SRS)在发现及定位瘤源性骨质软化症患者致病瘤灶的准确性.方法 6例临床疑诊瘤源性骨质软化症的患者,均于2周内分别行WB-DWI及SRS检查,评价两种检查方法发现致病瘤灶的价值,并以手术切除的病理诊断作为金标准,比较两者的敏感性、特异性及准确性.结果 手术病理证实的致病瘤灶包括软组织肿瘤2例(血管脂肪瘤及间叶组织肿瘤各1例)及骨肿瘤1例(恶性神经纤维瘤).WB-DWI和SRS发现瘤源性骨质软化症患者致病瘤灶的敏感性、特异性及准确性分别为:WB-DWI:33.33%、100%、66.67%:SRS:33.33%、66.67%、50%.两种方法比较差异无统计学意义(P>0.05).结论 对于成年的骨质软化症患者,应选择WB-DWI及SRS检查以寻找致病瘤灶,两者相互补充,为临床提供更加全面的信息.%Objective To compare the accuracy of whole body diffusion weighted magnetic resonance imaging (WB-DWI) with that of somatostatin receptor scintigraphy (SRS) in the detection and localization of the lesions in patients with oncogenic osteomalacia ( 00M). Methods Totally 6 patients with clinically suspected oncogenic osteomalacia were enrolled. All of them underwent WB-DWI and SRS within 2 weeks to evaluate the possible presence of tumors that lead to osteomalacia. Surgical and pathological findings were considered as the gold standard. The sensitivity, specificity, and accuracy were calculated. Results Pathology confirmed the diagnosis of two soft tissue tumors (including 1 angiolipoma and 1 mensenchumal tumor) and one bone tumor of malignant neurofibroma. The sensitivity, specificity, and accuracy in the identification of lesions in patients with oncogenic osteomalacia were 33. 33% , 100% , 66. 67% for WB-DWI and 33. 33% ,66. 67% , 50% for SRS (P>0. 05). Conclusion For adult patients with osteomalacia, WB-DWI and SRS can provide mutually supportive

  17. Effect of sulfur dioxide on expression of proto-oncogenes and tumor suppressor genes from rats.

    Science.gov (United States)

    Bai, Juli; Meng, Ziqiang

    2010-06-01

    Sulfur dioxide (SO(2)) is a ubiquitous air pollutant that is present in low concentrations in the urban air, and in higher concentrations in the working environment. In the present study, male Wistar rats were housed in exposure chambers and treated with 14.00 +/- 1.01, 28.00 +/- 1.77 and 56.00 +/- 3.44 mg m(-3) SO(2) for 6 h/day for 7 days, while control group was exposed to filtered air in the same condition. The mRNA and protein levels of proto-oncogenes (c-fos, c-jun, c-myc, and Ki-ras) and tumor suppressor genes (p53, Rb, and p16) were analyzed in lungs using a real-time reverse transcription-polymerase chain reaction (real-time RT-PCR) assay and Western blot analysis. The results showed that mRNA and protein levels of c-fos, c-jun, c-myc, Ki-ras, and p53 in lungs were increased in a dose-dependent manner, while mRNA and protein levels of Rb and p16 were decreased in lungs of rats after SO(2) inhalation. These results lead to a conclusion that SO(2) exposure could activate expressions of proto-oncogenes and suppress expressions of tumor suppressor genes, which might relate to the molecular mechanism of cocarcinogenic properties and potential carcinogenic effects of SO(2). According to previous studies, the results also indicated that promoter genes of apoptosis and tumor suppressor genes could produce apoptotic signals to antagonize the growth signals that arise from oncogenes. Understanding its molecular controls will benefit development of treatments for many diseases.

  18. Comparison of the clinical performance of an HPV mRNA test and an HPV DNA test in triage of atypical squamous cells of undetermined significance (ASC-US)

    DEFF Research Database (Denmark)

    Waldstrom, M; Ornskov, D

    2012-01-01

    The effect of triaging women with atypical squamous cells of undetermined significance (ASC-US) with human papillomavirus (HPV) DNA testing has been well documented. New tests detecting HPV E6/E7 mRNA are emerging, claiming to be more specific for detecting high-grade disease. We evaluated...... the clinical performance of two HPV tests: the Linear Array HPV genotyping test (LA) detecting HPV DNA from 37 oncogenic and non-oncogenic HPV types and the Aptima HPV assay detecting E6/E7 mRNA from 14 oncogenic HPV types....

  19. Radiosensitivity of tumor cells. Oncogenes and apoptosis

    Energy Technology Data Exchange (ETDEWEB)

    Peltenburg, L. T. C. [Leiden Univ., Leiden (Netherlands). Dept. of Clinical Oncology

    2000-12-01

    The success of treatment of cancer patients by radiotherapy largely depends on tumor radiosensitivity. Several molecular factors that determine the sensitivity of tumor cells to ionizing radiation have been identified during the last couple of years. Some of these factors are known as oncogenes and tumor suppressor genes. This review focuses on the influence of some of these molecular factors on a major determinant of radiosensitivity: i. e. programmed cell death or apoptosis. The crucial molecular step in ionizing radiation-induced apoptosis is the release of mitochondrial cytochrome c into the cell's cytosol. The ways the tumor suppressor protein p53, as well as the oncogenes ras and raf, c-myc and Bcl-2 can influence this process at different stages are presented. As will be discussed, the result of activation of an oncoprotein on tumor radiosensitivity depends on its mechanism of action and on the presence of other (oncogenic) factors, since complex interactions among many molecular factors determine the delicate balance between cell proliferation and cell death. The ongoing identification and characterization of factors influencing apoptosis will eventually make it possible to predict tumor radiosensitivity and thereby improve cancer treatment.

  20. JAC, a direct target of oncogenic transcription factor Jun, is involved in cell transformation and tumorigenesis.

    Science.gov (United States)

    Hartl, M; Reiter, F; Bader, A G; Castellazzi, M; Bister, K

    2001-11-20

    Using subtractive hybridization techniques, we have isolated a gene termed JAC that is strongly and specifically activated in avian fibroblasts transformed by the v-jun oncogene of avian sarcoma virus 17 (ASV17), but not in cells transformed by other oncogenic agents. Furthermore, JAC is highly expressed in cell lines derived from jun-induced avian fibrosarcomas. Kinetic analysis using a doxycycline-controlled conditional cell transformation system showed that expression of the 0.8-kb JAC mRNA is induced rapidly upon activation of the oncogenic v-jun allele. Nucleotide sequence analysis and transcriptional mapping revealed that the JAC gene contains two exons, with the longest ORF confined to exon 2. The deduced 68-amino acid chicken JAC protein is rich in cysteine residues and displays 37% sequence identity to mammalian high-sulfur keratin-associated proteins. The promoter region of JAC contains a consensus (5'-TGACTCA-3') and a nonconsensus (5'-TGAGTAA-3') AP-1 binding site in tandem, which are both specifically bound by the Gag-Jun hybrid protein encoded by ASV17. Mutational analysis revealed that the two AP-1 sites confer strong transcriptional activation by Gag-Jun in a synergistic manner. Ectopic expression of JAC in avian fibroblasts leads to anchorage-independent growth, strongly suggesting that deregulation of JAC is an essential event in jun-induced cell transformation and tumorigenesis.

  1. Gallium-68: chemistry and radiolabeled peptides exploring different oncogenic pathways.

    Science.gov (United States)

    Morgat, Clément; Hindié, Elif; Mishra, Anil K; Allard, Michèle; Fernandez, Philippe

    2013-03-01

    Abstract Early and specific tumor detection and also therapy selection and response evaluation are some challenges of personalized medicine. This calls for high sensitive and specific molecular imaging such as positron emission tomography (PET). The use of peptides for PET molecular imaging has undeniable advantages: possibility of targeting through peptide-receptor interaction, small size and low-molecular weight conferring good penetration in the tissue or at cellular level, low toxicity, no antigenicity, and possibility of wide choice for radiolabeling. Among β(+)-emitter radioelements, Gallium-68 is a very attractive positron-emitter compared with carbon-11 or fluorine-18 taking into account its easy production via a (68)Ge/(68)Ga generator and well established radiochemistry. Gallium-68 chemistry is based on well-defined coordination complexes with macrocycle or chelates having strong binding properties, particularly suitable for linking peptides that allow resistance to in vivo transchelation of the metal ion. Understanding specific and nonspecific molecular mechanisms involved in oncogenesis is one major key to develop new molecular imaging tools. The present review focuses on peptide signaling involved in different oncogenic pathways. This peptide signalization might be common for tumoral and non-tumoral processes or could be specific of an oncological process. This review describes gallium chemistry and different (68)Ga-radiolabeled peptides already in use or under development aiming at developing molecular PET imaging of different oncological processes.

  2. Assessment of human papillomavirus E6/E7 oncogene expression as cervical disease biomarker.

    Science.gov (United States)

    Fontecha, Nerea; Basaras, Miren; Hernáez, Silvia; Andía, Daniel; Cisterna, Ramón

    2016-11-05

    The aims of this study were to detect HPV E6/E7 mRNA expression in women with high-risk genotypes (HPV-16, -18, -31, -33 and -45) analysing its relationship with tissue pathology and 2) 2-year follow-up of E6/E7 mRNA tested group. Our samples were genotyped and classified by pathologists according to Bethesda system. After RNA extraction, E6/E7 oncogene mRNA detection was performed by NucliSens® EasyQ® HPV v1 Test (bioMérieux). The results of the present study showed that E6/E7 mRNA positivity rate was 68.29 % in women tested once and 69.56 % in women tested twice. According to tissue pathology, all samples with high-grade lesions were positive for mRNA. Among women with low-grade lesions varied over the years from 89.28 to 84 % in women tested once and from 77.77 to 70 % in tested twice. Among women without lesion, positivity rate maintained in women tested once (from 50 to 41.38 %) and decreased in tested twice, from 63.63 to 44.44 %. Regarding lesion evolution, mRNA positivity was higher in women with lesion progression (53.13 %) and in women with positive results in two tested samples (83.33 %). HPV E6/E7 mRNA detection may be an effective screening test and biomarker for cervical cancer in women infected with these five genotypes. Nonetheless, further studies are needed to standardize as routine triage test.

  3. Activation of proto-oncogenes by disruption of chromosome neighborhoods.

    Science.gov (United States)

    Hnisz, Denes; Weintraub, Abraham S; Day, Daniel S; Valton, Anne-Laure; Bak, Rasmus O; Li, Charles H; Goldmann, Johanna; Lajoie, Bryan R; Fan, Zi Peng; Sigova, Alla A; Reddy, Jessica; Borges-Rivera, Diego; Lee, Tong Ihn; Jaenisch, Rudolf; Porteus, Matthew H; Dekker, Job; Young, Richard A

    2016-03-25

    Oncogenes are activated through well-known chromosomal alterations such as gene fusion, translocation, and focal amplification. In light of recent evidence that the control of key genes depends on chromosome structures called insulated neighborhoods, we investigated whether proto-oncogenes occur within these structures and whether oncogene activation can occur via disruption of insulated neighborhood boundaries in cancer cells. We mapped insulated neighborhoods in T cell acute lymphoblastic leukemia (T-ALL) and found that tumor cell genomes contain recurrent microdeletions that eliminate the boundary sites of insulated neighborhoods containing prominent T-ALL proto-oncogenes. Perturbation of such boundaries in nonmalignant cells was sufficient to activate proto-oncogenes. Mutations affecting chromosome neighborhood boundaries were found in many types of cancer. Thus, oncogene activation can occur via genetic alterations that disrupt insulated neighborhoods in malignant cells.

  4. Oncogenic extracellular vesicles in brain tumour progression

    Directory of Open Access Journals (Sweden)

    Esterina eD'Asti

    2012-07-01

    Full Text Available The brain is a frequent site of neoplastic growth, including both primary and metastatic tumours. The clinical intractability of many brain tumours and their distinct biology are implicitly linked to the unique microenvironment of the central nervous system (CNS and cellular interactions within. Among the most intriguing forms of cellular interactions is that mediated by membrane-derived extracellular vesicles (EVs. Their biogenesis (vesiculation and uptake by recipient cells serves as a unique mechanism of intercellular trafficking of complex biological messages including the exchange of molecules that cannot be released through classical secretory pathways, or that are prone to extracellular degradation. Tumour cells produce EVs containing molecular effectors of several cancer-related processes such as growth, invasion, drug resistance, angiogenesis, and coagulopathy. Notably, tumour-derived EVs (oncosomes also contain oncogenic proteins, transcripts, DNA and microRNA (miR. Uptake of this material may change properties of the recipient cells and impact the tumour microenvironment. Examples of transformation-related molecules found in the cargo of tumour-derived EVs include the oncogenic epidermal growth factor receptor (EGFRvIII, tumour suppressors (PTEN and oncomirs (miR-520g. It is postulated that EVs circulating in blood or cerebrospinal fluid (CSF of brain tumour patients may be used to decipher molecular features (mutations of the underlying malignancy, reflect responses to therapy or molecular subtypes of primary brain tumours (e.g. glioma or medulloblastoma. It is possible that metastases to the brain may also emit EVs with clinically relevant oncogenic signatures. Thus EVs emerge as a novel and functionally important vehicle of intercellular communication that can mediate multiple biological effects. In addition, they provide a unique platform to develop molecular biomarkers in brain malignancies.

  5. Integrated, genome-wide screening for hypomethylated oncogenes in salivary gland adenoid cystic carcinoma

    Science.gov (United States)

    Shao, Chunbo; Sun, Wenyue; Tan, Marietta; Glazer, Chad A.; Bhan, Sheetal; Zhong, Xiaoli; Fakhry, Carole; Sharma, Rajni; Westra, William H.; Hoque, Mohammad O.; Moskaluk, Christopher A.; Sidransky, David; Califano, Joseph A.; Ha, Patrick K.

    2011-01-01

    Purpose Salivary gland adenoid cystic carcinoma (ACC) is a rare malignancy that is poorly understood. In order to look for relevant oncogene candidates under the control of promoter methylation, an integrated, genome-wide screen was performed. Experimental Design Global demethylation of normal salivary gland cell strains using 5-aza-2′-deoxycytidine (5-Aza dC) and Trichostatin A (TSA), followed by expression array analysis was performed. ACC-specific expression profiling was generated using expression microarray analysis of primary ACC and normal samples. Next, the two profiles were integrated to identify a subset of genes for further validation of promoter demethylation in ACC versus normal. Finally, promising candidates were further validated for mRNA, protein, and promoter methylation levels in larger ACC cohorts. Functional validation was then performed in cancer cell lines. Results We found 159 genes that were significantly re-expressed after 5-Aza dC/TSA treatment and overexpressed in ACC. After initial validation, eight candidates showed hypomethylation in ACC: AQP1, CECR1, C1QR1, CTAG2, P53AIP1, TDRD12, BEX1, and DYNLT3. Aquaporin 1 (AQP1) showed the most significant hypomethylation and was further validated. AQP1 hypomethylation in ACC was confirmed with two independent cohorts. Of note, there was significant overexpression of AQP1 in both mRNA and protein in the paraffin-embedded ACC cohort. Furthermore, AQP1 was up-regulated in 5-Aza dC/TSA treated SACC83. Lastly, AQP1 promoted cell proliferation and colony formation in SACC83. Conclusions Our integrated, genome-wide screening method proved to be an effective strategy for detecting novel oncogenes in ACC. AQP1 is a promising oncogene candidate for ACC and is transcriptionally regulated by promoter hypomethylation. PMID:21551254

  6. Melanoma: oncogenic drivers and the immune system

    Science.gov (United States)

    Karachaliou, Niki; Pilotto, Sara; Teixidó, Cristina; Viteri, Santiago; González-Cao, María; Riso, Aldo; Morales-Espinosa, Daniela; Molina, Miguel Angel; Chaib, Imane; Santarpia, Mariacarmela; Richardet, Eduardo; Bria, Emilio

    2015-01-01

    Advances and in-depth understanding of the biology of melanoma over the past 30 years have contributed to a change in the consideration of melanoma as one of the most therapy-resistant malignancies. The finding that oncogenic BRAF mutations drive tumor growth in up to 50% of melanomas led to a molecular therapy revolution for unresectable and metastatic disease. Moving beyond BRAF, inactivation of immune regulatory checkpoints that limit T cell responses to melanoma has provided targets for cancer immunotherapy. In this review, we discuss the molecular biology of melanoma and we focus on the recent advances of molecularly targeted and immunotherapeutic approaches. PMID:26605311

  7. Intracortical osteoblastic osteosarcoma with oncogenic rickets

    Energy Technology Data Exchange (ETDEWEB)

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

    1999-01-01

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

  8. Oncogenic activation of NF-kappaB.

    Science.gov (United States)

    Staudt, Louis M

    2010-06-01

    Recent genetic evidence has established a pathogenetic role for NF-kappaB signaling in cancer. NF-kappaB signaling is engaged transiently when normal B lymphocytes respond to antigens, but lymphomas derived from these cells accumulate genetic lesions that constitutively activate NF-kappaB signaling. Many genetic aberrations in lymphomas alter CARD11, MALT1, or BCL10, which constitute a signaling complex that is intermediate between the B-cell receptor and IkappaB kinase. The activated B-cell-like subtype of diffuse large B-cell lymphoma activates NF-kappaB by a variety of mechanisms including oncogenic mutations in CARD11 and a chronic active form of B-cell receptor signaling. Normal plasma cells activate NF-kappaB in response to ligands in the bone marrow microenvironment, but their malignant counterpart, multiple myeloma, sustains a variety of genetic hits that stabilize the kinase NIK, leading to constitutive activation of the classical and alternative NF-kappaB pathways. Various oncogenic abnormalities in epithelial cancers, including mutant K-ras, engage unconventional IkappaB kinases to activate NF-kappaB. Inhibition of constitutive NF-kappaB signaling in each of these cancer types induces apoptosis, providing a rationale for the development of NF-kappaB pathway inhibitors for the treatment of cancer.

  9. RNA extraction method is crucial for human papillomavirus E6/E7 oncogenes detection.

    Science.gov (United States)

    Fontecha, Nerea; Nieto, Maria Carmen; Andía, Daniel; Cisterna, Ramón; Basaras, Miren

    2017-03-09

    Human papillomavirus (HPV) DNA testing plays a main role in the management of cervical cancer, however to improve the specificity in cervical screening, there is a need to develop and validate different approaches that can identify women at risk for progressive disease. Nowadays, mRNA expression of viral E6 and E7 HPV oncogenes stands up as a potential biomarker to improve cervical screening. We aimed to validate a method for RNA extraction, detect HPV mRNA expression and, assess the relationship between E6/E7 mRNA expression and pathology of patients' lesions and progression. This study included 50 specimens that had been previously genotyped as HPV16, 18, 31, 33 and/or 45. Cervical swabs were extracted with three different RNA extraction methods -Nuclisens manual extraction kit (bioMérieux), High Pure Viral RNA Kit (Roche) and RNeasy Plus Mini kit (Qiagen)-, and mRNA was detected with NucliSens EasyQ HPV version 1 test (bioMérieux) afterwards. Association of oncogene expression with pathology and lesion progression was analyzed for each extraction method. E6/E7 mRNA positivity rate was higher in samples analyzed with bioMérieux (62%), followed by Roche (24%) and Qiagen (6%). Women with lesions and lesion progression showed a higher prevalence of viral RNA expression than women that had not lesions or with lesion persistence. While bioMérieux revealed a higher sensitivity (77.27%), Roche presented a higher PPV (75%) and an increased specificity (89.28%). Extraction methods based on magnetic beads provided better RNA yield than those based in columns. Both Nuclisens manual extraction kit (bioMérieux) and High Pure Viral RNA Kit (Roche) seemed to be adequate for E6/E7 mRNA detection. However, none of them revealed both high sensitivity and specificity values. Further studies are needed to obtain and validate a standard gold method for RNA expression detection, to be included as part of the routine cervical screening program.

  10. Mislocalized activation of oncogenic RTKs switches downstream signaling outcomes

    DEFF Research Database (Denmark)

    Choudhary, Chuna Ram; Olsen, Jesper V; Brandts, Christian

    2009-01-01

    Inappropriate activation of oncogenic kinases at intracellular locations is frequently observed in human cancers, but its effects on global signaling are incompletely understood. Here, we show that the oncogenic mutant of Flt3 (Flt3-ITD), when localized at the endoplasmic reticulum (ER), aberrant...

  11. Oncogenic Transformation of Human-Derived Gastric Organoids.

    Science.gov (United States)

    Bertaux-Skeirik, Nina; Centeno, Jomaris; Gao, Jian; Gabre, Joel; Zavros, Yana

    2016-08-19

    The culture of organoids has represented a significant advancement in the gastrointestinal research field. Previous research studies have described the oncogenic transformation of human intestinal and mouse gastric organoids. Here we detail the protocol for the oncogenic transformation and orthotopic transplantation of human-derived gastric organoids.

  12. Oncogenic pathways implicated in ovarian epithelial cancer.

    Science.gov (United States)

    Nicosia, Santo V; Bai, Wenlong; Cheng, Jin Q; Coppola, Domenico; Kruk, Patricia A

    2003-08-01

    Characterization of intracellular signaling pathways should lead to a better understanding of ovarian epithelial carcinogenesis and provide an opportunity to interfere with signal transduction targets involved in ovarian tumor cell growth, survival, and progression. Challenges toward such an effort are significant because many of these signals are part of cascades within an intricate and likely redundant intracellular signaling network (Fig.1). For instance, a given signal may activate a dual intracellular pathway (ie, MEK1-MAPK and PI3K/Akt required for fibronectin-dependent activation of matrix metalloproteinase 9). A single pathway also may transduce more than one biologic or oncogenic signal (ie, PI3K signaling in epithelial and endothelial cell growth and sprouting of neovessels). Despite these challenges, evidence for therapeutic targeting of signal transduction pathways is accumulating in human cancer. For instance, the EGF-specific tyrosine kinase inhibitor ZD 1839 (Iressa) may have a beneficial therapeutic effect on ovarian epithelial cancer. Therapy of this cancer may include inhibitors of PI kinase (quercetin), ezrin and PIP kinase (genistein). The G protein-coupled family of receptors, including LPA, also is an attractive target to drugs, although their frequent pleiotropic functions may be at times toxic and lack specificity. Because of the lack of notable toxicity, PI3K/Akt pathway inhibitors such as FTIs are a promising targeted therapy of ovarian epithelial cancer. Increasing insight into the oncogenic pathways involved in ovarian epithelial cancer also is helping clinicians to understand better the phenomenon of chemoresistance in this malignancy. Oncogenic activation of gamma-synuclein promotes cell survival and provides resistance to paclitaxel, but such a resistance is partially overcome by an MEK inhibitor that suppresses ERK activity. Ovarian epithelial cancer is a complex group of neoplasms with an overall poor prognosis. Comprehension of

  13. Enhancer hijacking activates GFI1 family oncogenes in medulloblastoma.

    Science.gov (United States)

    Northcott, Paul A; Lee, Catherine; Zichner, Thomas; Stütz, Adrian M; Erkek, Serap; Kawauchi, Daisuke; Shih, David J H; Hovestadt, Volker; Zapatka, Marc; Sturm, Dominik; Jones, David T W; Kool, Marcel; Remke, Marc; Cavalli, Florence M G; Zuyderduyn, Scott; Bader, Gary D; VandenBerg, Scott; Esparza, Lourdes Adriana; Ryzhova, Marina; Wang, Wei; Wittmann, Andrea; Stark, Sebastian; Sieber, Laura; Seker-Cin, Huriye; Linke, Linda; Kratochwil, Fabian; Jäger, Natalie; Buchhalter, Ivo; Imbusch, Charles D; Zipprich, Gideon; Raeder, Benjamin; Schmidt, Sabine; Diessl, Nicolle; Wolf, Stephan; Wiemann, Stefan; Brors, Benedikt; Lawerenz, Chris; Eils, Jürgen; Warnatz, Hans-Jörg; Risch, Thomas; Yaspo, Marie-Laure; Weber, Ursula D; Bartholomae, Cynthia C; von Kalle, Christof; Turányi, Eszter; Hauser, Peter; Sanden, Emma; Darabi, Anna; Siesjö, Peter; Sterba, Jaroslav; Zitterbart, Karel; Sumerauer, David; van Sluis, Peter; Versteeg, Rogier; Volckmann, Richard; Koster, Jan; Schuhmann, Martin U; Ebinger, Martin; Grimes, H Leighton; Robinson, Giles W; Gajjar, Amar; Mynarek, Martin; von Hoff, Katja; Rutkowski, Stefan; Pietsch, Torsten; Scheurlen, Wolfram; Felsberg, Jörg; Reifenberger, Guido; Kulozik, Andreas E; von Deimling, Andreas; Witt, Olaf; Eils, Roland; Gilbertson, Richard J; Korshunov, Andrey; Taylor, Michael D; Lichter, Peter; Korbel, Jan O; Wechsler-Reya, Robert J; Pfister, Stefan M

    2014-07-24

    Medulloblastoma is a highly malignant paediatric brain tumour currently treated with a combination of surgery, radiation and chemotherapy, posing a considerable burden of toxicity to the developing child. Genomics has illuminated the extensive intertumoral heterogeneity of medulloblastoma, identifying four distinct molecular subgroups. Group 3 and group 4 subgroup medulloblastomas account for most paediatric cases; yet, oncogenic drivers for these subtypes remain largely unidentified. Here we describe a series of prevalent, highly disparate genomic structural variants, restricted to groups 3 and 4, resulting in specific and mutually exclusive activation of the growth factor independent 1 family proto-oncogenes, GFI1 and GFI1B. Somatic structural variants juxtapose GFI1 or GFI1B coding sequences proximal to active enhancer elements, including super-enhancers, instigating oncogenic activity. Our results, supported by evidence from mouse models, identify GFI1 and GFI1B as prominent medulloblastoma oncogenes and implicate 'enhancer hijacking' as an efficient mechanism driving oncogene activation in a childhood cancer.

  14. The Exceptional Oncogenicity of HTLV-1.

    Science.gov (United States)

    Tagaya, Yutaka; Gallo, Robert C

    2017-01-01

    Human T-cell leukemia virus-1 (HTLV-1) is the first pathogenic human retrovirus identified in 1979 by the Gallo group. HTLV-1 causes fatal T-cell leukemia (adult T cell leukemia) and a progressive myelopahy (HTLV-1-associated myelopathy/ tropical spastic paraparesis, HAM/TSP) and other disorders. Since the discovery of HTLV-1, several other microorganisms are demonstrated to cause cancer in humans. In this article, we investigated the oncogenic capacity of HTLV-1, in comparison with those of other oncoviruses and one oncobacterium (Helicobacter pylori, H. Pylori) based on published literature. We conclude here that HTLV-1 is one of the most and may be the most carcinogenic among them and arguably one of the most potent of the known human carcinogens. This fact has not been noted before and is particularly important to justify why we need to study HTLV-1 as an important model of human viral oncogenesis.

  15. Glycerophospholipid profile in oncogene-induced senescence.

    Science.gov (United States)

    Cadenas, Cristina; Vosbeck, Sonja; Hein, Eva-Maria; Hellwig, Birte; Langer, Alice; Hayen, Heiko; Franckenstein, Dennis; Büttner, Bettina; Hammad, Seddik; Marchan, Rosemarie; Hermes, Matthias; Selinski, Silvia; Rahnenführer, Jörg; Peksel, Begüm; Török, Zsolt; Vígh, László; Hengstler, Jan G

    2012-09-01

    Alterations in lipid metabolism and in the lipid composition of cellular membranes are linked to the pathology of numerous diseases including cancer. However, the influence of oncogene expression on cellular lipid profile is currently unknown. In this work we analyzed changes in lipid profiles that are induced in the course of ERBB2-expression mediated premature senescence. As a model system we used MCF-7 breast cancer cells with doxycycline-inducible expression of NeuT, an oncogenic ERBB2 variant. Affymetrix gene array data showed NeuT-induced alterations in the transcription of many enzymes involved in lipid metabolism, several of which (ACSL3, CHPT1, PLD1, LIPG, MGLL, LDL and NPC1) could be confirmed by quantitative realtime PCR. A study of the glycerophospholipid and lyso-glycerophospholipid profiles, obtained by high performance liquid chromatography coupled to Fourier-transform ion cyclotron resonance-mass spectrometry revealed senescence-associated changes in numerous lipid species, including mitochondrial lipids. The most prominent changes were found in PG(34:1), PG(36:1) (increased) and LPE(18:1), PG(40:7) and PI(36:1) (decreased). Statistical analysis revealed a general trend towards shortened phospholipid acyl chains in senescence and a significant trend to more saturated acyl chains in the class of phosphatidylglycerol. Additionally, the cellular cholesterol content was elevated and accumulated in vacuoles in senescent cells. These changes were accompanied by increased membrane fluidity. In mitochondria, loss of membrane potential along with altered intracellular distribution was observed. In conclusion, we present a comprehensive overview of altered cholesterol and glycerophospholipid patterns in senescence, showing that predominantly mitochondrial lipids are affected and lipid species less susceptible to peroxidation are increased.

  16. The oncogenic action of ionizing radiation on rat skin

    Energy Technology Data Exchange (ETDEWEB)

    Burns, F.J.

    1991-01-01

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

  17. Genomic profiling identifies GATA6 as a candidate oncogene amplified in pancreatobiliary cancer.

    Directory of Open Access Journals (Sweden)

    Kevin A Kwei

    2008-05-01

    Full Text Available Pancreatobiliary cancers have among the highest mortality rates of any cancer type. Discovering the full spectrum of molecular genetic alterations may suggest new avenues for therapy. To catalogue genomic alterations, we carried out array-based genomic profiling of 31 exocrine pancreatic cancers and 6 distal bile duct cancers, expanded as xenografts to enrich the tumor cell fraction. We identified numerous focal DNA amplifications and deletions, including in 19% of pancreatobiliary cases gain at cytoband 18q11.2, a locus uncommonly amplified in other tumor types. The smallest shared amplification at 18q11.2 included GATA6, a transcriptional regulator previously linked to normal pancreas development. When amplified, GATA6 was overexpressed at both the mRNA and protein levels, and strong immunostaining was observed in 25 of 54 (46% primary pancreatic cancers compared to 0 of 33 normal pancreas specimens surveyed. GATA6 expression in xenografts was associated with specific microarray gene-expression patterns, enriched for GATA binding sites and mitochondrial oxidative phosphorylation activity. siRNA mediated knockdown of GATA6 in pancreatic cancer cell lines with amplification led to reduced cell proliferation, cell cycle progression, and colony formation. Our findings indicate that GATA6 amplification and overexpression contribute to the oncogenic phenotypes of pancreatic cancer cells, and identify GATA6 as a candidate lineage-specific oncogene in pancreatobiliary cancer, with implications for novel treatment strategies.

  18. Alternative translation of the proto-oncogene c-myc by an internal ribosome entry site.

    Science.gov (United States)

    Nanbru, C; Lafon, I; Audigier, S; Gensac, M C; Vagner, S; Huez, G; Prats, A C

    1997-12-19

    The human proto-oncogene c-myc encodes two proteins, c-Myc1 and c-Myc2, from two initiation codons, CUG and AUG, respectively. It is also transcribed from four alternative promoters (P0, P1, P2, and P3), giving rise to different RNA 5'-leader sequences, the long sizes of which suggest that they must be inefficiently translated by the classical ribosome scanning mechanism. Here we have examined the influence of three c-myc mRNA 5'-leaders on the translation of chimeric myc-CAT mRNAs. We observed that in the reticulocyte rabbit lysate, these 5'-leaders lead to cap-independent translation initiation. To determine whether this kind of initiation resulted from the presence of an internal ribosome entry site (IRES), COS-7 cells were transfected with bicistronic vectors containing the different c-myc 5'-leaders in the intercistronic region. An IRES was identified, requiring elements located within the P2 leader, between nucleotides -363 and -94 upstream from the CUG start codon. This is the first demonstration of the existence of IRES-dependent translation for a proto-oncogene. This IRES could be a translation enhancer, allowing activation of c-myc expression under the control of trans-acting factors and in response to specific cell stimuli.

  19. Detection of E6/E7 HPV oncogene transcripts as biomarker of cervical intaepithelial displasia

    Directory of Open Access Journals (Sweden)

    Mauro Carcheri

    2009-09-01

    Full Text Available It is widely accepted that only persistent infection with high risk types of Human Papillomavirus (HPV HR is a significant risk factor for the development of an invasive squamous cervical cancer. The overexpression of viral oncogenes E6/E7 of HPV is considered a necessary process for incurring in a malignant phenotype.A HPV infection can be identified by detection of HPV DNA in biological samples, but the DNAbased tests cannot delineate between transient or persistent and potentially transforming infection. Instead there is many evidence to suggest that detection of HPV gene expression may constitute a more specific approach to highlight a clinically significant infection. Especially seems that the detection of E6/E7 transcripts can be usefully used for identify the women with a persistent HPV infection that will can induce a future cervical cancer. The aim of our study is to investigate if the detection of oncogenic viral gene activity by detecting transcripts of the E6 and E7 genes can be most usefull of HPV-DNA test in the triage of ASCUS or low grade cervical lesions. Our results confirm that HPV E6/E7 mRNA test can be considered a promising method to stratify HPV positive women for risk of future high-grade cervical lesions or cervical intaepithelial neoplasia.

  20. Antineoplastic Effects of siRNA against TMPRSS2-ERG Junction Oncogene in Prostate Cancer.

    Directory of Open Access Journals (Sweden)

    Giorgia Urbinati

    Full Text Available TMPRSS2-ERG junction oncogene is present in more than 50% of patients with prostate cancer and its expression is frequently associated with poor prognosis. Our aim is to achieve gene knockdown by siRNA TMPRSS2-ERG and then to assess the biological consequences of this inhibition. First, we designed siRNAs against the two TMPRSS2-ERG fusion variants (III and IV, most frequently identified in patients' biopsies. Two of the five siRNAs tested were found to efficiently inhibit mRNA of both TMPRSS2-ERG variants and to decrease ERG protein expression. Microarray analysis further confirmed ERG inhibition by both siRNAs TMPRSS2-ERG and revealed one common down-regulated gene, ADRA2A, involved in cell proliferation and migration. The siRNA against TMPRSS2-ERG fusion variant IV showed the highest anti-proliferative effects: Significantly decreased cell viability, increased cleaved caspase-3 and inhibited a cluster of anti-apoptotic proteins. To propose a concrete therapeutic approach, siRNA TMPRSS2-ERG IV was conjugated to squalene, which can self-organize as nanoparticles in water. The nanoparticles of siRNA TMPRSS2-ERG-squalene injected intravenously in SCID mice reduced growth of VCaP xenografted tumours, inhibited oncoprotein expression and partially restored differentiation (decrease in Ki67. In conclusion, this study offers a new prospect of treatment for prostate cancer based on siRNA-squalene nanoparticles targeting TMPRSS2-ERG junction oncogene.

  1. Modulation of junction tension by tumor suppressors and proto-oncogenes regulates cell-cell contacts.

    Science.gov (United States)

    Bosveld, Floris; Guirao, Boris; Wang, Zhimin; Rivière, Mathieu; Bonnet, Isabelle; Graner, François; Bellaïche, Yohanns

    2016-02-15

    Tumor suppressors and proto-oncogenes play crucial roles in tissue proliferation. Furthermore, de-regulation of their functions is deleterious to tissue architecture and can result in the sorting of somatic rounded clones minimizing their contact with surrounding wild-type (wt) cells. Defects in the shape of somatic clones correlate with defects in proliferation, cell affinity, cell-cell adhesion, oriented cell division and cortical contractility. Combining genetics, live-imaging, laser ablation and computer simulations, we aim to analyze whether distinct or similar mechanisms can account for the common role of tumor suppressors and proto-oncogenes in cell-cell contact regulation. In Drosophila epithelia, the tumor suppressors Fat (Ft) and Dachsous (Ds) regulate cell proliferation, tissue morphogenesis, planar cell polarity and junction tension. By analyzing the evolution over time of ft mutant cells and clones, we show that ft clones reduce their cell-cell contacts with the surrounding wt tissue in the absence of concomitant cell divisions and over-proliferation. This contact reduction depends on opposed changes of junction tensions in the clone bulk and its boundary with neighboring wt tissue. More generally, either clone bulk or boundary junction tension is modulated by the activation of Yorkie, Myc and Ras, yielding similar contact reductions with wt cells. Together, our data highlight mechanical roles for proto-oncogene and tumor suppressor pathways in cell-cell interactions.

  2. Oncogenic osteomalacia associated with soft tissue chondromyxoid fibroma

    Energy Technology Data Exchange (ETDEWEB)

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

    2001-08-01

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

  3. Identification of Novel Small Molecule Inhibitors of Oncogenic RET Kinase

    OpenAIRE

    Marialuisa Moccia; Qingsong Liu; Teresa Guida; Giorgia Federico; Annalisa Brescia; Zheng Zhao; Hwan Geun Choi; Xianming Deng; Li Tan; Jinhua Wang; Marc Billaud; Gray, Nathanael S.; Francesca Carlomagno; Massimo Santoro

    2015-01-01

    Oncogenic mutation of the RET receptor tyrosine kinase is observed in several human malignancies. Here, we describe three novel type II RET tyrosine kinase inhibitors (TKI), ALW-II-41-27, XMD15-44 and HG-6-63-01, that inhibit the cellular activity of oncogenic RET mutants at two digit nanomolar concentration. These three compounds shared a 3-trifluoromethyl-4-methylpiperazinephenyl pharmacophore that stabilizes the 'DFG-out' inactive conformation of RET activation loop. They blocked RET-media...

  4. LIN28 Expression in malignant germ cell tumors downregulates let-7 and increases oncogene levels.

    Science.gov (United States)

    Murray, Matthew J; Saini, Harpreet K; Siegler, Charlotte A; Hanning, Jennifer E; Barker, Emily M; van Dongen, Stijn; Ward, Dawn M; Raby, Katie L; Groves, Ian J; Scarpini, Cinzia G; Pett, Mark R; Thornton, Claire M; Enright, Anton J; Nicholson, James C; Coleman, Nicholas

    2013-08-01

    Despite their clinicopathologic heterogeneity, malignant germ cell tumors (GCT) share molecular abnormalities that are likely to be functionally important. In this study, we investigated the potential significance of downregulation of the let-7 family of tumor suppressor microRNAs in malignant GCTs. Microarray results from pediatric and adult samples (n = 45) showed that LIN28, the negative regulator of let-7 biogenesis, was abundant in malignant GCTs, regardless of patient age, tumor site, or histologic subtype. Indeed, a strong negative correlation existed between LIN28 and let-7 levels in specimens with matched datasets. Low let-7 levels were biologically significant, as the sequence complementary to the 2 to 7 nt common let-7 seed "GAGGUA" was enriched in the 3' untranslated regions of mRNAs upregulated in pediatric and adult malignant GCTs, compared with normal gonads (a mixture of germ cells and somatic cells). We identified 27 mRNA targets of let-7 that were upregulated in malignant GCT cells, confirming significant negative correlations with let-7 levels. Among 16 mRNAs examined in a largely independent set of specimens by quantitative reverse transcription PCR, we defined negative-associations with let-7e levels for six oncogenes, including MYCN, AURKB, CCNF, RRM2, MKI67, and C12orf5 (when including normal control tissues). Importantly, LIN28 depletion in malignant GCT cells restored let-7 levels and repressed all of these oncogenic let-7 mRNA targets, with LIN28 levels correlating with cell proliferation and MYCN levels. Conversely, ectopic expression of let-7e was sufficient to reduce proliferation and downregulate MYCN, AURKB, and LIN28, the latter via a double-negative feedback loop. We conclude that the LIN28/let-7 pathway has a critical pathobiologic role in malignant GCTs and therefore offers a promising target for therapeutic intervention. ©2013 AACR.

  5. Inhibition of Ras oncogenic activity by Ras protooncogenes.

    Science.gov (United States)

    Diaz, Roberto; Lue, Jeffrey; Mathews, Jeremy; Yoon, Andrew; Ahn, Daniel; Garcia-España, Antonio; Leonardi, Peter; Vargas, Marcelo P; Pellicer, Angel

    2005-01-10

    Point mutations in ras genes have been found in a large number and wide variety of human tumors. These oncogenic Ras mutants are locked in an active GTP-bound state that leads to a constitutive and deregulated activation of Ras function. The dogma that ras oncogenes are dominant, whereby the mutation of a single allele in a cell will predispose the host cell to transformation regardless of the presence of the normal allele, is being challenged. We have seen that increasing amounts of Ras protooncogenes are able to inhibit the activity of the N-Ras oncogene in the activation of Elk in NIH 3T3 cells and in the formation of foci. We have been able to determine that the inhibitory effect is by competition between Ras protooncogenes and the N-Ras oncogene that occurs first at the effector level at the membranes, then at the processing level and lastly at the effector level in the cytosol. In addition, coexpression of the N-Ras protooncogene in thymic lymphomas induced by the N-Ras oncogene is associated with increased levels of p107, p130 and cyclin A and decreased levels of Rb. In the present report, we have shown that the N-Ras oncogene is not truly dominant over Ras protooncogenes and their competing activities might be depending on cellular context.

  6. Peroxisome proliferator-activated receptor γ (PPARγ) mediates a Ski oncogene-induced shift from glycolysis to oxidative energy metabolism.

    Science.gov (United States)

    Ye, Fang; Lemieux, Hélène; Hoppel, Charles L; Hanson, Richard W; Hakimi, Parvin; Croniger, Colleen M; Puchowicz, Michelle; Anderson, Vernon E; Fujioka, Hisashi; Stavnezer, Ed

    2011-11-18

    Overexpression of the Ski oncogene induces oncogenic transformation of chicken embryo fibroblasts (CEFs). However, unlike most other oncogene-transformed cells, Ski-transformed CEFs (Ski-CEFs) do not display the classical Warburg effect. On the contrary, Ski transformation reduced lactate production and glucose utilization in CEFs. Compared with CEFs, Ski-CEFs exhibited enhanced TCA cycle activity, fatty acid catabolism through β-oxidation, glutamate oxidation, oxygen consumption, as well as increased numbers and mass of mitochondria. Interestingly, expression of PPARγ, a key transcription factor that regulates adipogenesis and lipid metabolism, was dramatically elevated at both the mRNA and protein levels in Ski-CEFs. Accordingly, PPARγ target genes that are involved in lipid uptake, transport, and oxidation were also markedly up-regulated by Ski. Knocking down PPARγ in Ski-CEFs by RNA interference reversed the elevated expression of these PPARγ target genes, as well as the shift to oxidative metabolism and the increased mitochondrial biogenesis. Moreover, we found that Ski co-immunoprecipitates with PPARγ and co-activates PPARγ-driven transcription.

  7. Leukemia Inhibitory Factor Downregulates Human Papillomavirus-16 Oncogene Expression and Inhibits the Proliferation of Cervical Carcinoma Cells

    Directory of Open Access Journals (Sweden)

    Joseph M. Bay

    2011-01-01

    Full Text Available The constitutive proliferation and resistance to differentiation and apoptosis of neoplastic cervical cells depend on sustained expression of human papillomavirus oncogenes. Inhibition of these oncogenes is a goal for the prevention of progression of HPV-induced neoplasias to cervical cancer. SiHa cervical cancer cells were transfected with an HPV-16 promoter reporter construct and treated with leukemia inhibitory factor (LIF, a human cytokine of the interleukin 6 superfamily. SiHa and CaSki cervical cancer cells were also assessed for proliferation by MTT precipitation, programmed cell death by flow cytometry, and HPV E6 and E7 expression by real-time PCR. LIF-treated cervical cancer cells showed significantly reduced HPV LCR activation, reduced levels of E6 and E7 mRNA, and reduced proliferation. We report the novel use of LIF to inhibit viral oncogene expression in cervical cancer cells, with concomitant reduction in proliferation suggesting re-engagement of cell-cycle regulation.

  8. Expression of the proto-oncogenes c-met and c-kit and their ligands, hepatocyte growth factor/scatter factor and stem cell factor, in SCLC cell lines and xenografts

    DEFF Research Database (Denmark)

    Rygaard, K; Nakamura, T; Spang-Thomsen, M

    1993-01-01

    We examined a panel of 25 small cell lung cancer (SCLC) cell lines and nude mouse xenografts for expression of the proto-oncogenes c-met and c-kit, and for expression of the corresponding ligands, hepatocyte growth factor (HGF) (also known as scatter factor (SF)), and stem cell factor (SCF......), respectively. Expression of mRNA was detected by Northern blotting, and c-met and c-kit protein expression was detected by Western blotting and immunocytochemistry. c-met and c-kit mRNA was expressed in 22 of the examined cell lines or xenografts, and coexpression of the two proto-oncogenes was observed in 20...... tumours. Expression of c-met and c-kit protein paralleled in the mRNA expression. HGF/SF mRNA was expressed in two of the examined tumours, and only one of these also expressed the c-met proto-oncogene. SCF mRNA was expressed in 19 of the examined tumours, and in 18 of these coexpression of c-kit and SCF...

  9. Identification of Novel Small Molecule Inhibitors of Oncogenic RET Kinase.

    Directory of Open Access Journals (Sweden)

    Marialuisa Moccia

    Full Text Available Oncogenic mutation of the RET receptor tyrosine kinase is observed in several human malignancies. Here, we describe three novel type II RET tyrosine kinase inhibitors (TKI, ALW-II-41-27, XMD15-44 and HG-6-63-01, that inhibit the cellular activity of oncogenic RET mutants at two digit nanomolar concentration. These three compounds shared a 3-trifluoromethyl-4-methylpiperazinephenyl pharmacophore that stabilizes the 'DFG-out' inactive conformation of RET activation loop. They blocked RET-mediated signaling and proliferation with an IC50 in the nM range in fibroblasts transformed by the RET/C634R and RET/M918T oncogenes. They also inhibited autophosphorylation of several additional oncogenic RET-derived point mutants and chimeric oncogenes. At a concentration of 10 nM, ALW-II-41-27, XMD15-44 and HG-6-63-01 inhibited RET kinase and signaling in human thyroid cancer cell lines carrying oncogenic RET alleles; they also inhibited proliferation of cancer, but not non-tumoral Nthy-ori-3-1, thyroid cells, with an IC50 in the nM range. The three compounds were capable of inhibiting the 'gatekeeper' V804M mutant which confers substantial resistance to established RET inhibitors. In conclusion, we have identified a type II TKI scaffold, shared by ALW-II-41-27, XMD15-44 and HG-6-63-01, that may be used as novel lead for the development of novel agents for the treatment of cancers harboring oncogenic activation of RET.

  10. Identification of Novel Small Molecule Inhibitors of Oncogenic RET Kinase.

    Science.gov (United States)

    Moccia, Marialuisa; Liu, Qingsong; Guida, Teresa; Federico, Giorgia; Brescia, Annalisa; Zhao, Zheng; Choi, Hwan Geun; Deng, Xianming; Tan, Li; Wang, Jinhua; Billaud, Marc; Gray, Nathanael S; Carlomagno, Francesca; Santoro, Massimo

    2015-01-01

    Oncogenic mutation of the RET receptor tyrosine kinase is observed in several human malignancies. Here, we describe three novel type II RET tyrosine kinase inhibitors (TKI), ALW-II-41-27, XMD15-44 and HG-6-63-01, that inhibit the cellular activity of oncogenic RET mutants at two digit nanomolar concentration. These three compounds shared a 3-trifluoromethyl-4-methylpiperazinephenyl pharmacophore that stabilizes the 'DFG-out' inactive conformation of RET activation loop. They blocked RET-mediated signaling and proliferation with an IC50 in the nM range in fibroblasts transformed by the RET/C634R and RET/M918T oncogenes. They also inhibited autophosphorylation of several additional oncogenic RET-derived point mutants and chimeric oncogenes. At a concentration of 10 nM, ALW-II-41-27, XMD15-44 and HG-6-63-01 inhibited RET kinase and signaling in human thyroid cancer cell lines carrying oncogenic RET alleles; they also inhibited proliferation of cancer, but not non-tumoral Nthy-ori-3-1, thyroid cells, with an IC50 in the nM range. The three compounds were capable of inhibiting the 'gatekeeper' V804M mutant which confers substantial resistance to established RET inhibitors. In conclusion, we have identified a type II TKI scaffold, shared by ALW-II-41-27, XMD15-44 and HG-6-63-01, that may be used as novel lead for the development of novel agents for the treatment of cancers harboring oncogenic activation of RET.

  11. Myc Regulation of mRNA Cap Methylation

    Science.gov (United States)

    Cowling, Victoria H.; Cole, Michael D.

    2010-01-01

    The c-myc proto-oncogene regulates the expression of 15% to 20% of all genes, depending on the cell type, and the regulation is usually modest (1.5- to 2.0-fold). The authors discovered that in addition to regulating mRNA abundance, c-Myc regulates the formation of the 7-methylguanosine cap on many mRNAs, including transcriptional target genes and others not transcriptionally activated. Because the 7-methylguanosine cap is required for effective translation, enhanced methyl cap formation leads to increased protein production from Myc-responsive genes that exceeds the transcriptional induction. Increased cap methylation is linked to Myc-dependent enhanced activity of 2 critical kinases, TFIIH and p-TEFb, which phosphorylate the RNA polymerase II carboxy-terminal domain (CTD). Phosphorylation of the CTD recruits RNGTT and RNMT, the enzymes involved in mRNA capping, to the nascent transcript. Evidence is accumulating that enhanced cap methylation makes a significant contribution to Myc-dependent gene regulation and protein production. PMID:21170289

  12. Stable oncogenic transformation induced by microcell-mediated gene transfer

    Institute of Scientific and Technical Information of China (English)

    吕有勇; Donald G.Blair

    1995-01-01

    Oncogenes have been identified using DNA-mediated transfection, but the size of the transferable and unrearranged DNA, gene rearrangement and amplification which occur during the transfection process limit the use of the techniques. We have evaluated microcell-mediated gene transfer techniques for the transfer and analysis of dominant oncogenes. MNNG-HOS, a transformed human cell line which contained the met oncogene mapping to human chromosome 7 was infected with retroviruses carrying drug resistance markers and used to optimize microcell preparation and transfer. Stable and drug-resistant hybrids containing single human chromosomes as well as the foci of the transformed cells containing the activated met oncogene and intact hitman chromosomes were obtained. Hybridization analysis with probes (i.e. collA2, pJ3.11) mapping up to 1 Mb away from met shows that the cells from the individual focr contain different amounts of apparently unrearranged human DNA associated with the oncogene, and the microcell-g

  13. Oncogenes and RNA splicing of human tumor viruses.

    Science.gov (United States)

    Ajiro, Masahiko; Zheng, Zhi-Ming

    2014-09-01

    Approximately 10.8% of human cancers are associated with infection by an oncogenic virus. These viruses include human papillomavirus (HPV), Epstein-Barr virus (EBV), Merkel cell polyomavirus (MCV), human T-cell leukemia virus 1 (HTLV-1), Kaposi's sarcoma-associated herpesvirus (KSHV), hepatitis C virus (HCV) and hepatitis B virus (HBV). These oncogenic viruses, with the exception of HCV, require the host RNA splicing machinery in order to exercise their oncogenic activities, a strategy that allows the viruses to efficiently export and stabilize viral RNA and to produce spliced RNA isoforms from a bicistronic or polycistronic RNA transcript for efficient protein translation. Infection with a tumor virus affects the expression of host genes, including host RNA splicing factors, which play a key role in regulating viral RNA splicing of oncogene transcripts. A current prospective focus is to explore how alternative RNA splicing and the expression of viral oncogenes take place in a cell- or tissue-specific manner in virus-induced human carcinogenesis.

  14. Oncogenic roles of PRL-3 in FLT3-ITD induced acute myeloid leukaemia.

    Science.gov (United States)

    Park, Jung Eun; Yuen, Hiu Fung; Zhou, Jian Biao; Al-Aidaroos, Abdul Qader O; Guo, Ke; Valk, Peter J; Zhang, Shu Dong; Chng, Wee Joo; Hong, Cheng William; Mills, Ken; Zeng, Qi

    2013-09-01

    FLT3-ITD mutations are prevalent mutations in acute myeloid leukaemia (AML). PRL-3, a metastasis-associated phosphatase, is a downstream target of FLT3-ITD. This study investigates the regulation and function of PRL-3 in leukaemia cell lines and AML patients associated with FLT3-ITD mutations. PRL-3 expression is upregulated by the FLT3-STAT5 signalling pathway in leukaemia cells, leading an activation of AP-1 transcription factors via ERK and JNK pathways. PRL-3-depleted AML cells showed a significant decrease in cell growth. Clinically, high PRL-3 mRNA expression was associated with FLT3-ITD mutations in four independent AML datasets with 1158 patients. Multivariable Cox-regression analysis on our Cohort 1 with 221 patients identified PRL-3 as a novel prognostic marker independent of other clinical parameters. Kaplan-Meier analysis showed high PRL-3 mRNA expression was significantly associated with poorer survival among 491 patients with normal karyotype. Targeting PRL-3 reversed the oncogenic effects in FLT3-ITD AML models in vitro and in vivo. Herein, we suggest that PRL-3 could serve as a prognostic marker to predict poorer survival and as a promising novel therapeutic target for AML patients.

  15. Ras Oncogene-Mediated Progressive Silencing of Extracellular Superoxide Dismutase in Tumorigenesis

    Directory of Open Access Journals (Sweden)

    Francesca Cammarota

    2015-01-01

    Full Text Available Extracellular superoxide dismutase (SOD3 is a secreted enzyme that uses superoxide anion as a substrate in a dismutase reaction that results in the formation of hydrogen peroxide. Both of these reactive oxygen species affect growth signaling in cells. Although SOD3 has growth-supporting characteristics, the expression of SOD3 is downregulated in epithelial cancer cells. In the current work, we studied the mechanisms regulating SOD3 expression in vitro using thyroid cell models representing different stages of thyroid cancer. We demonstrate that a low level of RAS activation increases SOD3 mRNA synthesis that then gradually decreases with increasing levels of RAS activation and the decreasing degree of differentiation of the cancer cells. Our data indicate that SOD3 regulation can be divided into two classes. The first class involves RAS–driven reversible regulation of SOD3 expression that can be mediated by the following mechanisms: RAS GTPase regulatory genes that are responsible for SOD3 self-regulation; RAS-stimulated p38 MAPK activation; and RAS-activated increased expression of the mir21 microRNA, which inversely correlates with sod3 mRNA expression. The second class involves permanent silencing of SOD3 mediated by epigenetic DNA methylation in cells that represent more advanced cancers. Therefore, the work suggests that SOD3 belongs to the group of ras oncogene-silenced genes.

  16. Acute leukemia viruses E26 and avian myeloblastosis virus have related transformation-specific RNA sequences but different genetic structures, gene products, and oncogenic properties

    Science.gov (United States)

    Bister, Klaus; Nunn, Michael; Moscovici, Carlo; Perbal, Bernard; Baluda, Marcel A.; Duesberg, Peter H.

    1982-01-01

    expression of related onc sequences: AMV is thought to encode a transforming protein via a subgenomic mRNA, whereas E26 codes for a gag-related polyprotein via genomic RNA. It is speculated that differences in the oncogenic properties of E26 and AMV are due to differences in their genetic structures and gene products. Images PMID:6285358

  17. Oncogene-mediated transformation of fetal rat colon in vitro.

    Science.gov (United States)

    Pories, S; Jaros, K; Steele, G; Pauley, A; Summerhayes, I C

    1992-05-01

    Short-term maintenance of fetal rat colonic tissue in vitro has been demonstrated using a collagen matrix organ culture system. The introduction of single (v-myc, v-rasH, v-src) oncogenes or combinations of oncogenes (v-myc/rasH, v-myc/src) into normal colon mucosal elements was established using retroviral vectors, resulting in enhanced proliferation and migration of epithelial cells from the lumen of tissue implants. Expression of a single oncogene in normal colon epithelium did not result in the establishment of cell lines. In contrast, expression of cooperating oncogenic elements resulted in cell lines in greater than 80% of experiments, revealing different morphological characteristics dependent upon the oncogene combination used. Confirmation of the expression of viral transcripts was determined using Northern blot analysis and viral oncoprotein expression using Western blot analysis (p21) and an immunoprecipitation kinase assay (src). Expression of keratin filaments was lost following passaging of cell lines but could be induced by the myc/ras transformants by growth on Rat-1 feeder layers. This induction phenomenon was not observed with myc/src lines, and although these expressed high levels of sucrase isomaltase the epithelial origin of these cells is unclear. Karyotypic analysis performed on three myc/ras-transformed cell lines revealed a normal chromosome complement associated with transformation. In this report we describe a novel in vitro transformation system for normal rat colonic epithelium mediated by the introduction of oncogene elements using different retroviral vector constructs. The potential to generate cell lines representing different stages of neoplastic progression using relevant genetic components presents significant advantages for the study of cellular and molecular interactions underlying colon neoplastic progression.

  18. Comprehensive gene and microRNA expression profiling reveals a role for miRNAs in the oncogenic roles of SphK1 in papillary thyroid cancer.

    Science.gov (United States)

    Liang, Weiwei; Xie, Zhiwei; Cui, Weiling; Guo, Yan; Xu, Lijuan; Wu, Jueheng; Guan, Hongyu

    2017-04-01

    The oncogenic roles of sphingosine kinase 1 (SphK1) in various cancers, including thyroid cancer, have been well demonstrated. However, the microRNAs (miRNAs) associated with the oncogenic roles of SphK1 remain largely unknown. Global gene and miRNA expression in TPC1-Vector and TPC1-SphK1 cells was analyzed using digital gene expression (DGE) analysis and small RNA-seq, respectively. miRNA-mRNA interactions were explored by microT-CDS, and the predicted networks were visualized using CytoScape(®). Cell invasion and migration were assessed by performing Transwell invasion and wound-healing assays. Luciferase reporter and immunoblot assays were used to evaluate the targeting of fibronectin 1 (FN1) by miR-144-3p. In this study, we found that overexpression of SphK1 differentially regulates the expression of 46 miRNAs and 506 mRNAs in papillary thyroid cancer (PTC) TPC1 cells. Combining bioinformatics predictions of mRNA targets with DGE data on mRNA expression allowed us to identify the mRNA targets of deregulated miRNAs. The direct interaction between miR-144-3p and FN1, which mediates the pro-invasive role of SphK1 in PTC cells, was experimentally validated. Our results demonstrated that SphK1 overexpression drives a regulatory network governing miRNA and mRNA expression in PTC cells. We also demonstrated the roles played by miR-144-3p and FN1 in mediating the oncogenic function of SphK1, which enhanced the understanding of the etiology of PTC.

  19. In Silico Analysis of Oncogenes for Renal Cancer

    Directory of Open Access Journals (Sweden)

    Sim-Hui Tee

    2012-01-01

    Full Text Available Computational tools and methods play a vital role in handling and analyzing a large volume of genomic data. In cancer research, in silico methods such as computational algorithm and protein databases are indispensable. In this paper, we adopted an in silico approach to analyze oncogenes that cause  renal cancer. Our objective is to identify and analyze the genes which are over expressed in the renal cancer tissues. The identification of oncogenes for renal cancer could provide directions and insights for molecular cancer treatment.

  20. HuR knockdown changes the oncogenic potential of oral cancer cells.

    Science.gov (United States)

    Kakuguchi, Wataru; Kitamura, Tetsuya; Kuroshima, Takeshi; Ishikawa, Makoto; Kitagawa, Yoshimasa; Totsuka, Yasunori; Shindoh, Masanobu; Higashino, Fumihiro

    2010-04-01

    HuR binds to AU-rich element-containing mRNA to protect them from rapid degradation. Here, we show that knockdown of HuR changes the oncogenic properties of oral cancer cells. Oral squamous cell carcinoma cell lines, HSC-3 and Ca9.22, which express HuR protein and cytoplasmic AU-rich element mRNA more abundantly than normal cells, were subjected to HuR knockdown. In the HuR-knockdown cancer cells, the cytoplasmic expression of c-fos, c-myc, and COX-2 mRNAs was inhibited compared with those in cells that had been transfected with a control small interfering RNA, and the half-lives of these mRNAs were shorter than those of their counterparts in the control cells. HuR-knockdown cells failed to make colonies in soft agar, suggesting that the cells had lost their ability for anchorage-independent cell growth. Additionally, the motile and invasive activities of the cells decreased remarkably by HuR knockdown. Furthermore, the expression of cell cycle-related proteins, such as cyclin A, cyclin B1, cyclin D1, and cyclin-dependent kinase 1, was reduced in HuR-knockdown cancer cells, and HuR bound to cdk1 mRNA to stabilize it. These findings suggest that HuR knockdown changes the features of oral cancer cells, at least in part, by affecting their cell cycle and shows potential as an effective therapeutic approach.

  1. 3-(2-Chloropropyl amide)-4-methoxy-N-phenylbenzamide inhibits expression of HPV oncogenes in human cervical cancer cell.

    Science.gov (United States)

    Han, Fang; Li, Yanping; Lu, Qiaoni; Ma, Linlin; Wang, Huiqiang; Jiang, Jiandong; Li, Zhuorong; Li, Yuhuan

    2017-07-28

    Human papillomaviruses (HPVs) are the primary causative agents for cervical cancer, and HPV oncoproteins E6 and E7 are known to be the main reason for the onset and maintenance of the malignancies. Therefore, inhibition of viral E6 and E7 oncoproteins expression represents a viable strategy to cervical cancer therapies. This study is to evaluate the antiviral effect of a novel N-Phenylbenzamide derivative, 3-(2-Chloropropyl amide)-4-methoxy-N-phenylbenzamide (L17), against HPV16 in vitro and identify its associated mechanism of action in cervical cancer cells. The cytotoxic effect of L17 was assessed by MTT assay. The mRNA and protein levels of E6 and E7 oncogenes were analyzed by quantitative real-time reverse transcription PCR (qRT-PCR) and Western blot, respectively. p53 and Rb protein levels were also detected by Western blot. The effect of L17 on cell cycle was analyzed by flow cytometry. The cytotoxic effect of L17 was greater in cervical carcinoma cells than in normal cells. L17 significantly reduced the expression of HPV16 E6 and E7 mRNA and protein, at least partly by enhancing degradation of HPV16 E6 and E7 mRNA. Moreover, reduced expression of E6 and E7 induced by L17 resulted in the up-regulation of p53 and Rb expression, which subsequently induced CaSki cells arrest at G0/G1 phase. L17 has antiviral activity through suppressing E6 and E7 oncogene expression and could inhibit CaSki cell proliferating by inducing cells arrest at G0/G1 phase at nontoxic concentration, implying that L17 might be exploited as a candidate agent for HPV-associated cervical cancer prevention and treatment.

  2. Effects of sulfur dioxide derivatives on expression of oncogenes and tumor suppressor genes in human bronchial epithelial cells.

    Science.gov (United States)

    Qin, Guohua; Meng, Ziqiang

    2009-04-01

    Sulfur dioxide (SO(2)) is a major air pollutant suspected to act as a promoter or co-carcinogen. The present study was designed to investigate whether SO(2) derivatives (bisulfite and sulfite) had effects on the expression of several proto-oncogenes and tumor suppressor genes in cultured human bronchial epithelial (BEP2D) cells. The mRNA and protein levels were measured by real-time RT-PCR and western blotting, respectively, following exposure to differing SO(2)-derivative concentrations and exposure times. SO(2) derivatives caused mRNA and protein over-expression of c-fos, c-jun, and c-myc at all tested doses (0.001-2mM). Over-expression of H-ras and p53 were observed in cells receiving the highest concentration (0.1-2mM), as well as the under-expression of p16 and Rb. The over-expression of c-fos and c-jun was observed after 24h recovery. The expression of c-myc and H-ras decreased to base line levels while the p53 expression decreased compared with control after 24h recovery. The mRNA and protein expression of p16 and Rb remained at initial levels after 24h recovery. The data support the hypothesis that SO(2) derivatives could cause the activation of proto-oncogenes and inactivation of tumor suppressor genes and SO(2) derivatives may play a role in the pathogenesis of SO(2)-associated lung cancer.

  3. Estradiol and Estrogen Receptor Agonists Oppose Oncogenic Actions of Leptin in HepG2 Cells.

    Directory of Open Access Journals (Sweden)

    Minqian Shen

    Full Text Available Obesity is a significant risk factor for certain cancers, including hepatocellular carcinoma (HCC. Leptin, a hormone secreted by white adipose tissue, precipitates HCC development. Epidemiology data show that men have a much higher incidence of HCC than women, suggesting that estrogens and its receptors may inhibit HCC development and progression. Whether estrogens antagonize oncogenic action of leptin is uncertain. To investigate potential inhibitory effects of estrogens on leptin-induced HCC development, HCC cell line HepG2 cells were treated with leptin in combination with 17 β-estradiol (E2, estrogen receptor-α (ER-α selective agonist PPT, ER-β selective agonist DPN, or G protein-coupled ER (GPER selective agonist G-1. Cell number, proliferation, and apoptosis were determined, and leptin- and estrogen-related intracellular signaling pathways were analyzed. HepG2 cells expressed a low level of ER-β mRNA, and leptin treatment increased ER-β expression. E2 suppressed leptin-induced HepG2 cell proliferation and promoted cell apoptosis in a dose-dependent manner. Additionally E2 reversed leptin-induced STAT3 and leptin-suppressed SOCS3, which was mainly achieved by activation of ER-β. E2 also enhanced ERK via activating ER-α and GPER and activated p38/MAPK via activating ER-β. To conclude, E2 and its receptors antagonize the oncogenic actions of leptin in HepG2 cells by inhibiting cell proliferation and stimulating cell apoptosis, which was associated with reversing leptin-induced changes in SOCS3/STAT3 and increasing p38/MAPK by activating ER-β, and increasing ERK by activating ER-α and GPER. Identifying roles of different estrogen receptors would provide comprehensive understanding of estrogenic mechanisms in HCC development and shed light on potential treatment for HCC patients.

  4. Integrin-linked kinase overexpression and its oncogenic role in promoting tumorigenicity of hepatocellular carcinoma.

    Directory of Open Access Journals (Sweden)

    Jenny Chan

    Full Text Available BACKGROUND: Integrin-linked kinase (ILK was first discovered as an integrin β1-subunit binding protein. It localizes at the focal adhesions and is involved in cytoskeleton remodeling. ILK overexpression and its dysregulated signaling cascades have been reported in many human cancers. Aberrant expression of ILK influenced a wide range of signaling pathways and cellular functions. Although ILK has been well characterized in many malignancies, its role in hepatocellular carcinoma (HCC is still largely unknown. METHODOLOGY/PRINCIPAL FINDINGS: Quantitative PCR analysis was used to examine ILK mRNA expression in HCC clinical samples. It was shown that ILK was overexpressed in 36.9% (21/57 of HCC tissues when compared to the corresponding non-tumorous livers. The overall ILK expression level was significantly higher in tumorous tissues (P = 0.004, with a significant stepwise increase in expression level along tumor progression from tumor stage I to IV (P = 0.045. ILK knockdown stable clones were established in two HCC cell lines, BEL7402 and HLE, and were subjected to different functional assays. Knockdown of ILK significantly suppressed HCC cell growth, motility and invasion in vitro and inhibited tumorigenicity in vivo. Western blot analysis revealed a reduced phosphorylated-Akt (pAkt at Serine-473 expression in ILK knockdown stable clones when compared to control clones. CONCLUSION/SIGNIFICANCE: This study provides evidence about the clinical relevance of ILK in hepatocarcinogenesis. ILK was found to be progressively elevated along HCC progression. Here our findings also provide the first validation about the oncogenic capacity of ILK in vivo by suppressing its expression in HCC cells. The oncogenic role of ILK is implicated to be mediated by Akt pathway.

  5. ESPL1 is a candidate oncogene of luminal B breast cancers.

    Science.gov (United States)

    Finetti, Pascal; Guille, Arnaud; Adelaide, José; Birnbaum, Daniel; Chaffanet, Max; Bertucci, François

    2014-08-01

    ESPL1/separase is a putative oncogene of luminal B breast cancers. Histoclinical correlations of its expression have never been explored in large series of breast tumors, and specifically in the luminal subtype. In a pooled series of invasive breast carcinomas profiled using DNA microarrays, we identified 3,074 luminal cases, including 1,307 luminal B tumors, in which we searched for correlations between ESPL1 mRNA expression and molecular and histoclinical features. Compared to normal breast samples, ESPL1 was overexpressed in 52 % of luminal tumors, and much more frequently in luminal B (83 %) than luminal A tumors (29 %). In luminal breast cancers, higher ESPL1 expression was associated with poor-prognosis criteria (age ≤ 50 years, ductal type, advanced stage, large tumor size, lymph node-positive status, high grade, PR-negative status, luminal B subtype) and with poor metastasis-free survival in both uni- and multivariate analyses. This independent prognostic value was also observed in luminal B tumors only, and persisted when compared with gene expression signatures (PAM50, Recurrence Score, Mammaprint, EndoPredict) currently proposed to refine the indications of adjuvant chemotherapy in hormone receptor-positive/HER2-negative breast cancer. We also confirmed the observations made with experimental mouse models: ESPL1-overexpressing luminal tumors showed complex genomic profiles and molecular features of chromosomal instability and loss of tumor suppressor genes (P53 and Rb). Our results reinforce the idea that ESPL1 is a candidate oncogene in luminal B cancers. Its expression may help improve the prognostication. Inhibiting ESPL1 may represent a promising therapeutic approach for these poor-prognosis tumors.

  6. The mystery of oncogenic KRAS: Lessons from studying its wild-type counter part.

    Science.gov (United States)

    Chang, Yuan-I; Damnernsawad, Alisa; Kong, Guangyao; You, Xiaona; Wang, Demin; Zhang, Jing

    2016-07-22

    Using conditional knock-in mouse models, we and others have shown that despite the very high sequence identity between Nras and Kras proteins, oncogenic Kras displays a much stronger leukemogenic activity than oncogenic Nras in vivo. In this manuscript, we will summarize our recent work of characterizing wild-type Kras function in adult hematopoiesis and in oncogenic Kras-induced leukemogenesis. We attribute the strong leukemogenic activity of oncogenic Kras to 2 unique aspects of Kras signaling. First, Kras is required in mediating cell type- and cytokine-specific ERK1/2 signaling. Second, oncogenic Kras, but not oncogenic Nras, induces hyperactivation of wild-type Ras, which significantly enhances Ras signaling in vivo. We will also discuss a possible mechanism that mediates oncogenic Kras-evoked hyperactivation of wild-type Ras and a potential approach to down-regulate oncogenic Kras signaling.

  7. Role of ets Oncogenes in the Progression of Breast Cancer

    Science.gov (United States)

    1998-10-01

    Mazabraud A. (1988). Cancer Kato J, Matsuoka M, Polyak K, Massague J and Sherr CJ. Genet. Cytogenet., 32, 229-238. (1994). Cell, 79, 487-496. Vairo G...Francisco LV , Roach JC, Argonza R, D, Weber BL and EI-Deiryh WS. (1998). Oncogene, 16, King MC and Ostrander EA. (1996). Human Mol. Genet., 1713-1721. 5

  8. c-Abl antagonizes the YAP oncogenic function.

    Science.gov (United States)

    Keshet, R; Adler, J; Ricardo Lax, I; Shanzer, M; Porat, Z; Reuven, N; Shaul, Y

    2015-06-01

    YES-associated protein (YAP) is a central transcription coactivator that functions as an oncogene in a number of experimental systems. However, under DNA damage, YAP activates pro-apoptotic genes in conjunction with p73. This program switching is mediated by c-Abl (Abelson murine leukemia viral oncogene) via phosphorylation of YAP at the Y357 residue (pY357). YAP as an oncogene coactivates the TEAD (transcriptional enhancer activator domain) family transcription factors. Here we asked whether c-Abl regulates the YAP-TEAD functional module. We found that DNA damage, through c-Abl activation, specifically depressed YAP-TEAD-induced transcription. Remarkably, c-Abl counteracts YAP-induced transformation by interfering with the YAP-TEAD transcriptional program. c-Abl induced TEAD1 phosphorylation, but the YAP-TEAD complex remained unaffected. In contrast, TEAD coactivation was compromised by phosphomimetic YAP Y357E mutation but not Y357F, as demonstrated at the level of reporter genes and endogenous TEAD target genes. Furthermore, YAP Y357E also severely compromised the role of YAP in cell transformation, migration, anchorage-independent growth, and epithelial-to-mesenchymal transition (EMT) in human mammary MCF10A cells. These results suggest that YAP pY357 lost TEAD transcription activation function. Our results demonstrate that YAP pY357 inactivates YAP oncogenic function and establish a role for YAP Y357 phosphorylation in cell-fate decision.

  9. Arsenic trioxide inhibits cell proliferation and human papillomavirus oncogene expression in cervical cancer cells

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Hongtao [Department of Pathology, School of Medicine, Southeast University, Nanjing 210009 (China); Gao, Peng [Department of Internal Medicine, University of Iowa, Iowa City, IA 52242 (United States); Zheng, Jie, E-mail: jiezheng54@126.com [Department of Pathology, School of Medicine, Southeast University, Nanjing 210009 (China)

    2014-09-05

    Highlights: • As{sub 2}O{sub 3} inhibits growth of cervical cancer cells and expression of HPV oncogenes in these cells. • HPV-negative cervical cancer cells are more sensitive to As{sub 2}O{sub 3} than HPV-positive cervical cancer cells. • HPV-18 positive cervical cancer cells are more sensitive to As{sub 2}O{sub 3} than HPV-16 positive cancer cells. • Down-regulation of HPV oncogenes by As{sub 2}O{sub 3} is partially due to the diminished AP-1 binding. - Abstract: Arsenic trioxide (As{sub 2}O{sub 3}) has shown therapeutic effects in some leukemias and solid cancers. However, the molecular mechanisms of its anticancer efficacy have not been clearly elucidated, particularly in solid cancers. Our previous data showed that As{sub 2}O{sub 3} induced apoptosis of human papillomavirus (HPV) 16 DNA-immortalized human cervical epithelial cells and cervical cancer cells and inhibited the expression of HPV oncogenes in these cells. In the present study, we systemically examined the effects of As{sub 2}O{sub 3} on five human cervical cancer cell lines and explored the possible molecular mechanisms. MTT assay showed that HPV-negative C33A cells were more sensitive to growth inhibition induced by As{sub 2}O{sub 3} than HPV-positive cervical cancer cells, and HPV 18-positive HeLa and C4-I cells were more sensitive to As{sub 2}O{sub 3} than HPV 16-positive CaSki and SiHa cells. After As{sub 2}O{sub 3} treatment, both mRNA and protein levels of HPV E6 and E7 obviously decreased in all HPV positive cell lines. In contrast, p53 and Rb protein levels increased in all tested cell lines. Transcription factor AP-1 protein expression decreased significantly in HeLa, CaSki and C33A cells with ELISA method. These results suggest that As{sub 2}O{sub 3} is a potential anticancer drug for cervical cancer.

  10. Images

    Data.gov (United States)

    National Aeronautics and Space Administration — Images for the website main pages and all configurations. The upload and access points for the other images are: Website Template RSW images BSCW Images HIRENASD...

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

    DEFF Research Database (Denmark)

    Evangelou, K; Bartkova, J; Kotsinas, A

    2013-01-01

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

  12. Main: MRNA3ENDTAH3 [PLACE

    Lifescience Database Archive (English)

    Full Text Available MRNA3ENDTAH3 S000069 17-May-1998 (last modified) kehi Cis element in 3' end region ...of wheat (T.a.) histone H3 mRNA; 3' end formation; Also found in histone genes of other plants, yeast, etc; histone H3; mRNA

  13. Transforming genes among three different oncogenic subgroups of human adenoviruses have similar replicative functions.

    Science.gov (United States)

    Brusca, J S; Chinnadurai, G

    1981-01-01

    We have examined the functional similarity of the transforming genes for replicative functions among three different subgroups of human adenoviruses (A, B, and C), using mutant complementation as an assay. A host range deletion mutant (dl201.2) of Ad2 (nononcogenic subgroup C) lacking about 5% of the viral DNA covering two early gene blocks (E1a and E1b) involved in cellular transformation was isolated and tested for its ability to replicate in nonpermissive KB cells in the presence of Ad7 (weakly oncogenic group B) or ad12 (highly oncogenic group A). The complementation of the mutant defect was demonstrated by cleaving the viral DNA extracted from mixed infected cells or the DNA extracted from purified virions from mixed infected cells with restriction endonuclease BamHI, which produces a different cleavage pattern with the DNA of each serotype. It was found that the defects in E1a plus E1b of dl201.2 could be complemented by Ad7 and Ad12, indicating that these genes in Ad2, Ad7, and Ad12 have similar functions during productive infection. Images PMID:7277578

  14. The use of Gene Ontology terms and KEGG pathways for analysis and prediction of oncogenes.

    Science.gov (United States)

    Xing, Zhihao; Chu, Chen; Chen, Lei; Kong, Xiangyin

    2016-11-01

    Oncogenes are a type of genes that have the potential to cause cancer. Most normal cells undergo programmed cell death, namely apoptosis, but activated oncogenes can help cells avoid apoptosis and survive. Thus, studying oncogenes is helpful for obtaining a good understanding of the formation and development of various types of cancers. In this study, we proposed a computational method, called OPM, for investigating oncogenes from the view of Gene Ontology (GO) and biological pathways. All investigated genes, including validated oncogenes retrieved from some public databases and other genes that have not been reported to be oncogenes thus far, were encoded into numeric vectors according to the enrichment theory of GO terms and KEGG pathways. Some popular feature selection methods, minimum redundancy maximum relevance and incremental feature selection, and an advanced machine learning algorithm, random forest, were adopted to analyze the numeric vectors to extract key GO terms and KEGG pathways. Along with the oncogenes, GO terms and KEGG pathways were discussed in terms of their relevance in this study. Some important GO terms and KEGG pathways were extracted using feature selection methods and were confirmed to be highly related to oncogenes. Additionally, the importance of these terms and pathways in predicting oncogenes was further demonstrated by finding new putative oncogenes based on them. This study investigated oncogenes based on GO terms and KEGG pathways. Some important GO terms and KEGG pathways were confirmed to be highly related to oncogenes. We hope that these GO terms and KEGG pathways can provide new insight for the study of oncogenes, particularly for building more effective prediction models to identify novel oncogenes. The program is available upon request. We hope that the new findings listed in this study may provide a new insight for the investigation of oncogenes. This article is part of a Special Issue entitled "System Genetics" Guest Editor

  15. High Risk Alpha Papillomavirus Oncogenes Impair the Homologous Recombination Pathway.

    Science.gov (United States)

    Wallace, Nicholas A; Khanal, Sujita; Robinson, Kristin L; Wendel, Sebastian O; Messer, Joshua J; Galloway, Denise A

    2017-08-02

    Persistent high risk genus α human papillomavirus (HPV) infections cause nearly every cervical carcinoma and a subset of tumors in the oropharyngeal tract. During the decades required for HPV-associated tumorigenesis, the cellular genome becomes significantly destabilized. Our analysis of cervical tumors from 4 separate data sets found a significant upregulation of the homologous recombination (HR) pathway genes. The increased abundance of HR proteins can be replicated in primary cells by expression of the two HPV oncogenes (E6 and E7) required for HPV-associated transformation. HPV E6 and E7 also enhanced the ability of HR proteins to form repair foci, yet both E6 and E7 reduce the ability of the HR pathway to complete double strand break (DSB) repair by about 50%. The HPV oncogenes hinder HR by allowing the process to begin at points in the cell cycle when the lack of a sister chromatid to serve as a homologous template prevents completion of the repair. Further, HPV E6 attenuates repair by causing RAD51 to be mislocalized away from both transient and persistent DSBs, while HPV E7 is only capable of impairing RAD51 localization to transient lesions. Finally, we show that the inability to robustly repair DSBs causes some of these lesions to be more persistent, a phenotype that correlates with increased integration of episomal DNA. Together these data support our hypothesis that HPV oncogenes contribute to the genomic instability observed in HPV-associated malignancies by attenuating the repair of damaged DNA.IMPORTANCE: This work expands the understanding of HPV biology, establishing a direct role for both HPV E6 and E7 in the destabilization of the host genome by blocking the homologous repair of DSBs. To our knowledge, this is the first time that both viral oncogenes were shown to disrupt this DSB repair pathway. We show that HPV E6 and E7 allow HR to initiate at an inappropriate part of the cell cycle. The mislocalization of RAD51 away from DSBs in cells

  16. Effect of growth hormone and serum on the expression of the proto-oncogenes c-jun and c-fos in insulin producing cells

    DEFF Research Database (Denmark)

    Petersen, Elisabeth D.; Billestrup, N; Nielsen, Jens Høiriis

    1990-01-01

    Expression of the proto-oncogenes c-fos and c-jun was analysed in the insulin producing rat tumor cell line, RIN 5AH. Addition of fetal calf serum (FCS) to serum-starved cells in the presence of cycloheximid induced a modest increase in c-fos and c-jun mRNA levels, whereas growth hormone (GH......RNA levels. These results suggest that the effects of GH on insulin producing cells are not mediated by activation of c-fos and c-jun transcription....

  17. Long-range Transcriptome Sequencing Reveals Cancer Cell Growth Regulatory Chimeric mRNA

    Directory of Open Access Journals (Sweden)

    Roberto Plebani

    2012-11-01

    Full Text Available mRNA chimeras from chromosomal translocations often play a role as transforming oncogenes. However, cancer transcriptomes also contain mRNA chimeras that may play a role in tumor development, which arise as transcriptional or post-transcriptional events. To identify such chimeras, we developed a deterministic screening strategy for long-range sequence analysis. High-throughput, long-read sequencing was then performed on cDNA libraries from major tumor histotypes and corresponding normal tissues. These analyses led to the identification of 378 chimeras, with an unexpectedly high frequency of expression (≈2 x 10-5 of all mRNA. Functional assays in breast and ovarian cancer cell lines showed that a large fraction of mRNA chimeras regulates cell replication. Strikingly, chimeras were shown to include both positive and negative regulators of cell growth, which functioned as such in a cell-type-specific manner. Replication-controlling chimeras were found to be expressed by most cancers from breast, ovary, colon, uterus, kidney, lung, and stomach, suggesting a widespread role in tumor development.

  18. The ETS family of oncogenic transcription factors in solid tumours.

    Science.gov (United States)

    Sizemore, Gina M; Pitarresi, Jason R; Balakrishnan, Subhasree; Ostrowski, Michael C

    2017-06-01

    Findings over the past decade have identified aberrant activation of the ETS transcription factor family throughout all stages of tumorigenesis. Specifically in solid tumours, gene rearrangement and amplification, feed-forward growth factor signalling loops, formation of gain-of-function co-regulatory complexes and novel cis-acting mutations in ETS target gene promoters can result in increased ETS activity. In turn, pro-oncogenic ETS signalling enhances tumorigenesis through a broad mechanistic toolbox that includes lineage specification and self-renewal, DNA damage and genome instability, epigenetics and metabolism. This Review discusses these different mechanisms of ETS activation and subsequent oncogenic implications, as well as the clinical utility of ETS factors.

  19. Malignant transformation of diploid human fibroblasts by transfection of oncogenes

    Energy Technology Data Exchange (ETDEWEB)

    McCormick, J.J.

    1992-01-01

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

  20. Regulation of apoptosis by the papillomavirus E6 oncogene

    Institute of Scientific and Technical Information of China (English)

    Ting-Ting Li; Li-Na Zhao; Zhi-Guo Liu; Ying Han; Dai-Ming Fan

    2005-01-01

    Infection with human papillomaviruses is strongly associated with the development of multiple cancers including esophageal squamous cell carcinoma. The HPV E6 gene is essential for the oncogenic potential of HPV.The recgulation of apoptosis by oncogene has been relatel to carcinogenesis closely; therefore, the modulation of E6 on cellular apoptosis has become a hot research topic recently. Inactivation of the pro-apoptotic tumor suppressor p53 by E6 is an important mechanism by which E6promotes cell growth; it is expected that inactivation of p53 by E6 should lead to a reduction in cellular apoptosis,numerous studies showed that E6 could in fact sensitize cells to apoptosis. The molecular basis for apoptosis modulation by E6 is poorly understood. In this article, we will present an overview of observations and current understanding of molecular basis for E6-induced apoptosis.

  1. Tumour microvesicles contain retrotransposon elements and amplified oncogene sequences

    Science.gov (United States)

    Balaj, Leonora; Lessard, Ryan; Dai, Lixin; Cho, Yoon-Jae; Pomeroy, Scott L.; Breakefield, Xandra O.; Skog, Johan

    2011-01-01

    Tumour cells release an abundance of microvesicles containing a selected set of proteins and RNAs. Here, we show that tumour microvesicles also carry DNA, which reflects the genetic status of the tumour, including amplification of the oncogene c-Myc. We also find amplified c-Myc in serum microvesicles from tumour-bearing mice. Further, we find remarkably high levels of retrotransposon RNA transcripts, especially for some human endogenous retroviruses, such as LINE-1 and Alu retrotransposon elements, in tumour microvesicles and these transposable elements could be transferred to normal cells. These findings expand the nucleic acid content of tumour microvesicles to include: elevated levels of specific coding and non-coding RNA and DNA, mutated and amplified oncogene sequences and transposable elements. Thus, tumour microvesicles contain a repertoire of genetic information available for horizontal gene transfer and potential use as blood biomarkers for cancer. PMID:21285958

  2. Advances on Driver Oncogenes of Squamous Cell Lung Cancer

    Directory of Open Access Journals (Sweden)

    Wei HONG

    2014-05-01

    Full Text Available Background and objective Lung cancer is the leading cause of cancer-related deaths worldwide. Next to adenocarcinoma, squamous cell carcinoma (SCC of the lung is the most frequent histologic subtype in non-small cell lung cancer. Several molecular alterations have been defined as "driver oncogenes" responsible for both the initiation and maintenance of the malignancy. The squamous cell carcinoma of the lung has recently shown peculiar molecular characteristics which relate with both carcinogenesis and response to targeted drugs. So far, about 40% of lung squamous cell carcinoma has been found harbouring driver oncogenes, in which fibroblast growth factor receptor 1 (FGFR1 plays important roles. In this review, we will report the mainly advances on some latest driver mutations of squamous cell lung cancer.

  3. Pharmacological strategies to target oncogenic KRAS signaling in pancreatic cancer.

    Science.gov (United States)

    Chuang, Hsiao-Ching; Huang, Po-Hsien; Kulp, Samuel K; Chen, Ching-Shih

    2017-03-01

    The clear importance of mutated KRAS as a therapeutic target has driven the investigation of multiple approaches to inhibit oncogenic KRAS signaling at different molecular levels. However, no KRAS-targeted therapy has reached the clinic to date, which underlies the intrinsic difficulty in developing effective, direct inhibitors of KRAS. Thus, this article provides an overview of the history and recent progress in the development of pharmacological strategies to target oncogenic KRAS with small molecule agents. Mechanistically, these KRAS-targeted agents can be classified into the following four categories. (1) Small-molecule RAS-binding ligands that prevent RAS activation by binding within or outside the nucleotide-binding motif. (2) Inhibitors of KRAS membrane anchorage. (3) Inhibitors that bind to RAS-binding domains of RAS-effector proteins. (4) Inhibitors of KRAS expression. The advantage and limitation of each type of these anti-KRAS agents are discussed.

  4. Mutations in the RET proto-oncogene in sporadic pheochromocytomas

    Energy Technology Data Exchange (ETDEWEB)

    Thibodeau, S.N.; Lindor, N.M.; Honchel, R. [Mayo Clinic and Foundation, Rochester, MN (United States)] [and others

    1994-09-01

    Mutations in the RET proto-oncogene have recently been demonstrated in kindreds with Multiple Endocrine Neoplasia (MEN) types 2A and 2B. Both of these autosomal dominant disorders are characterized by the development of neoplasia in cell lines of neural crest origin, such as medullary throid carcinomas and pheochromocytomas. Individuals with MEN 2B have, in addition, ganglioneuromas of the lips, tongue and colon, a marfanoid habitus, and corneal nerve thickening. Approximately 90% of patients with MEN 2A have a germline mutation in exons 10 or 11, while 95% of patients with MEN 2B have a T{yields}C transition in codon 918 of exon 16. In this study, pheochromocytomas from 29 individuals who had no clinical evidence of MEN 2A or 2B (sporadic) were examined for the presence of either germline or somatic mutations in exons 10, 11, and 16 of the RET proto-oncogene. Of the 29 tumors examined, 3 (10%) were found to have a mutation in one of the three exons. One tumor had a G{yields}A transition in codon 609 (exon 10), another had a 6 bp deletion encompassing codons 632 & 633 (exon 11), and the final tumor had a T{yields}C transition in codon 918 (exon 16). These mutations were not found in the corresponding normal DNA from these individuals, indicating that the mutation were somatic in origin. Although we cannot exclude the possibility of mutations in other regions of the RET proto-oncogene, our data suggests that: (1) individuals presenting with apparently sporadic pheochromocytomas are not likely to have undiagnosed MEN 2A or 2B; and (2) somatic mutations in the RET proto-oncogene contribute to the process of tumorigenesis in a small percentage of sporadic pheochromocytomas.

  5. PKC Epsilon: A Novel Oncogenic Player in Prostate Cancer

    Science.gov (United States)

    2014-09-01

    Malik, A., Zaman, N., Sarfaraz, S., Siddiqui, I. A., Syed, D. N. et al (2007). Combined inhibitory effects of green tea polyphenols and selective...not only in prostate cancer but also in several other epithelial cancers including lung , breast, and thyroid cancer8, 13, 20-26. Studies from our...Cvarepsilon is required for non-small cell lung carcinoma growth and regulates the expression of apoptotic genes. Oncogene 31: 2593-2600. 23 Hafeez, B. B

  6. Activation of oncogenes by radon progeny and x-rays

    Energy Technology Data Exchange (ETDEWEB)

    Ling, C.C.

    1990-01-01

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

  7. Phosphoglycerate Dehydrogenase: Potential Therapeutic Target and Putative Metabolic Oncogene

    Directory of Open Access Journals (Sweden)

    Cheryl K. Zogg

    2014-01-01

    Full Text Available Exemplified by cancer cells’ preference for glycolysis, for example, the Warburg effect, altered metabolism in tumorigenesis has emerged as an important aspect of cancer in the past 10–20 years. Whether due to changes in regulatory tumor suppressors/oncogenes or by acting as metabolic oncogenes themselves, enzymes involved in the complex network of metabolic pathways are being studied to understand their role and assess their utility as therapeutic targets. Conversion of glycolytic intermediate 3-phosphoglycerate into phosphohydroxypyruvate by the enzyme phosphoglycerate dehydrogenase (PHGDH—a rate-limiting step in the conversion of 3-phosphoglycerate to serine—represents one such mechanism. Forgotten since classic animal studies in the 1980s, the role of PHGDH as a potential therapeutic target and putative metabolic oncogene has recently reemerged following publication of two prominent papers near-simultaneously in 2011. Since that time, numerous studies and a host of metabolic explanations have been put forward in an attempt to understand the results observed. In this paper, I review the historic progression of our understanding of the role of PHGDH in cancer from the early work by Snell through its reemergence and rise to prominence, culminating in an assessment of subsequent work and what it means for the future of PHGDH.

  8. Oncogenic Kras initiates leukemia in hematopoietic stem cells.

    Directory of Open Access Journals (Sweden)

    Amit J Sabnis

    2009-03-01

    Full Text Available How oncogenes modulate the self-renewal properties of cancer-initiating cells is incompletely understood. Activating KRAS and NRAS mutations are among the most common oncogenic lesions detected in human cancer, and occur in myeloproliferative disorders (MPDs and leukemias. We investigated the effects of expressing oncogenic Kras(G12D from its endogenous locus on the proliferation and tumor-initiating properties of murine hematopoietic stem and progenitor cells. MPD could be initiated by Kras(G12D expression in a highly restricted population enriched for hematopoietic stem cells (HSCs, but not in common myeloid progenitors. Kras(G12D HSCs demonstrated a marked in vivo competitive advantage over wild-type cells. Kras(G12D expression also increased the fraction of proliferating HSCs and reduced the overall size of this compartment. Transplanted Kras(G12D HSCs efficiently initiated acute T-lineage leukemia/lymphoma, which was associated with secondary Notch1 mutations in thymocytes. We conclude that MPD-initiating activity is restricted to the HSC compartment in Kras(G12D mice, and that distinct self-renewing populations with cooperating mutations emerge during cancer progression.

  9. Oncogenic transformation of diverse gastrointestinal tissues in primary organoid culture.

    Science.gov (United States)

    Li, Xingnan; Nadauld, Lincoln; Ootani, Akifumi; Corney, David C; Pai, Reetesh K; Gevaert, Olivier; Cantrell, Michael A; Rack, Paul G; Neal, James T; Chan, Carol W-M; Yeung, Trevor; Gong, Xue; Yuan, Jenny; Wilhelmy, Julie; Robine, Sylvie; Attardi, Laura D; Plevritis, Sylvia K; Hung, Kenneth E; Chen, Chang-Zheng; Ji, Hanlee P; Kuo, Calvin J

    2014-07-01

    The application of primary organoid cultures containing epithelial and mesenchymal elements to cancer modeling holds promise for combining the accurate multilineage differentiation and physiology of in vivo systems with the facile in vitro manipulation of transformed cell lines. Here we used a single air-liquid interface culture method without modification to engineer oncogenic mutations into primary epithelial and mesenchymal organoids from mouse colon, stomach and pancreas. Pancreatic and gastric organoids exhibited dysplasia as a result of expression of Kras carrying the G12D mutation (Kras(G12D)), p53 loss or both and readily generated adenocarcinoma after in vivo transplantation. In contrast, primary colon organoids required combinatorial Apc, p53, Kras(G12D) and Smad4 mutations for progressive transformation to invasive adenocarcinoma-like histology in vitro and tumorigenicity in vivo, recapitulating multi-hit models of colorectal cancer (CRC), as compared to the more promiscuous transformation of small intestinal organoids. Colon organoid culture functionally validated the microRNA miR-483 as a dominant driver oncogene at the IGF2 (insulin-like growth factor-2) 11p15.5 CRC amplicon, inducing dysplasia in vitro and tumorigenicity in vivo. These studies demonstrate the general utility of a highly tractable primary organoid system for cancer modeling and driver oncogene validation in diverse gastrointestinal tissues.

  10. PRG3 induces Ras-dependent oncogenic cooperation in gliomas

    Science.gov (United States)

    Yakubov, Eduard; Chen, Daishi; Broggini, Thomas; Sehm, Tina; Majernik, Gökce Hatipoglu; Hock, Stefan W.; Schwarz, Marc; Engelhorn, Tobias; Doerfler, Arnd; Buchfelder, Michael; Eyupoglu, Ilker Y.; Savaskan, Nicolai E.

    2016-01-01

    Malignant gliomas are one of the most devastating cancers in humans. One characteristic hallmark of malignant gliomas is their cellular heterogeneity with frequent genetic lesions and disturbed gene expression levels conferring selective growth advantage. Here, we report on the neuronal-associated growth promoting gene PRG3 executing oncogenic cooperation in gliomas. We have identified perturbed PRG3 levels in human malignant brain tumors displaying either elevated or down-regulated PRG3 levels compared to non-transformed specimens. Further, imbalanced PRG3 levels in gliomas foster Ras-driven oncogenic amplification with increased proliferation and cell migration although angiogenesis was unaffected. Hence, PRG3 interacts with RasGEF1 (RasGRF1/CDC25), undergoes Ras-induced challenges, whereas deletion of the C-terminal domain of PRG3 (PRG3ΔCT) inhibits Ras. Moreover PRG3 silencing makes gliomas resistant to Ras inhibition. In vivo disequilibrated PRG3 gliomas show aggravated proliferation, invasion, and deteriorate clinical outcome. Thus, our data show that the interference with PRG3 homeostasis amplifies oncogenic properties and foster the malignancy potential in gliomas. PMID:27058420

  11. CRAF R391W is a melanoma driver oncogene

    Science.gov (United States)

    Atefi, Mohammad; Titz, Bjoern; Tsoi, Jennifer; Avramis, Earl; Le, Allison; Ng, Charles; Lomova, Anastasia; Lassen, Amanda; Friedman, Michael; Chmielowski, Bartosz; Ribas, Antoni; Graeber, Thomas G.

    2016-01-01

    Approximately 75% of melanomas have known driver oncogenic mutations in BRAF, NRAS, GNA11 or GNAQ, while the mutations providing constitutive oncogenic signaling in the remaining melanomas are not known. We established a melanoma cell line from a tumor with none of the common driver mutations. This cell line demonstrated a signaling profile similar to BRAF-mutants, but lacked sensitivity to the BRAF inhibitor vemurafenib. RNA-seq mutation data implicated CRAF R391W as the alternative driver mutation of this melanoma. CRAF R391W was homozygous and over expressed. These melanoma cells were highly sensitive to CRAF, but not BRAF knockdown. In reconstitution experiments, CRAF R391W, but not CRAF WT, transformed NIH3T3 cells in soft-agar colony formation assays, increased kinase activity in vitro, induced MAP kinase signaling and conferred vemurafenib resistance. MAP kinase inducing activity was dependent on CRAF dimerization. Thus, CRAF is a bona fide alternative oncogene for BRAF/NRAS/GNAQ/GNA11 wild type melanomas. PMID:27273450

  12. Immunohistochemical analysis of ras oncogene p21 product in human gastric carcinomas and their adjacent mucosas.

    Science.gov (United States)

    Carneiro, F; David, L; Sunkel, C; Lopes, C; Sobrinho-Simões, M

    1992-04-01

    In an attempt to clarify the relationship between ras oncogene expression and the clinico-pathological features of malignant and pre-malignant lesions of the stomach we undertook the immunohistochemical study of the expression of ras gene p21 product in a series of eighty gastric carcinomas and their respective adjacent mucosas. In two cases the mRNA of Ha-ras was also studied by in situ hybridization. The majority of gastric carcinomas as well as their adjacent non-neoplastic mucosas expressed ras gene product. There was a significant relationship between the expression of ras gene p21 product and the morphologic pattern of the tumours. An enhanced ras expression was found in several conditions regarded as precursor lesions of intestinal and/or diffuse types of gastric carcinoma (dysplasia, foveolar hyperplasia and even the neck zone of normal-appearing gastric glands, namely in the mucosa adjacent to diffuse carcinomas). Ras expression was actually more prominent in most of these conditions than in their respective adjacent carcinomas. No significant relationship was found between ras expression and invasiveness of the wall, nodal metastases and venous invasion.

  13. Arsenic trioxide inhibits cell proliferation and human papillomavirus oncogene expression in cervical cancer cells.

    Science.gov (United States)

    Wang, Hongtao; Gao, Peng; Zheng, Jie

    2014-09-05

    Arsenic trioxide (As2O3) has shown therapeutic effects in some leukemias and solid cancers. However, the molecular mechanisms of its anticancer efficacy have not been clearly elucidated, particularly in solid cancers. Our previous data showed that As2O3 induced apoptosis of human papillomavirus (HPV) 16 DNA-immortalized human cervical epithelial cells and cervical cancer cells and inhibited the expression of HPV oncogenes in these cells. In the present study, we systemically examined the effects of As2O3 on five human cervical cancer cell lines and explored the possible molecular mechanisms. MTT assay showed that HPV-negative C33A cells were more sensitive to growth inhibition induced by As2O3 than HPV-positive cervical cancer cells, and HPV 18-positive HeLa and C4-I cells were more sensitive to As2O3 than HPV 16-positive CaSki and SiHa cells. After As2O3 treatment, both mRNA and protein levels of HPV E6 and E7 obviously decreased in all HPV positive cell lines. In contrast, p53 and Rb protein levels increased in all tested cell lines. Transcription factor AP-1 protein expression decreased significantly in HeLa, CaSki and C33A cells with ELISA method. These results suggest that As2O3 is a potential anticancer drug for cervical cancer.

  14. 人胎冠状动脉原位杂交c-myc和jun原癌基因表达%Expression of proto - oncogenes c - myc and jun in human coronary artery ruring development

    Institute of Scientific and Technical Information of China (English)

    蔡维君; 陈新平; 伍校琼; 罗学港

    2004-01-01

    目的研究原癌基因c-myc和jun在人胎冠状动脉发育过程中的表达与平滑肌细胞增殖的关系.方法用原位杂交方法检测,胎龄分别为16周、22周(因治疗需要引产)的胎儿和意外死亡的足月胎儿冠状动脉前降支c-myc mRNA和jun mRNA的表达水平.杂交反应产物用图像分析仪(MIAS300)作定量分析.结果C-myc mRNA原位杂交反应产物与被测血管区域面积的百分比在16周、22周和足月胎儿分别是70、56和10;Jun mRNA的杂交信反应产物与被测血管区域面积的百分比在这三个时期分别是68、53和8.两个原癌基因在不同阶段的表达均具有显著性差异.结论本实验首次报道c-myc和jun在人胎冠状动脉发育过程中平滑肌的表达图型,c-myc和jun在胎儿冠状动脉平滑肌细胞增殖和内膜的形成过程中可能具有重要的调控作用.%Objective: To investigate the expression of protooncogenes, c - myc and jun, in human coronary artery during development. Methods: In situ hybridization was employed to detect c - myc mRNA and jun mRNA in human coronary artery from aborted fetus with embryonic ages from week 16 to 22 due to treatment requirements. In addition, 3 cases of full term human fetus died of accident were also studied. Hybridized signals were quantified with a computer - assisted image - analyzing system ( MIAS 300 ). Results: The ratio of hybridized signal of c - myc to the area of vascular wall detected were 0.7, 0.54 and 0.10 respectively corresponding to the embryonic ages, 16 weeks,22 weeks and full term. Similar results with the ratio of 0.68, 0.53 and 0.08 for jun mRNA at above embryonic ages was also found. The levels of c - myc and jun mRNA expressed at different embryonic stage showed a significant difference. Conclusions: We first reported the expression of proto - oncogenes, c - myc and jun, in human coronary artery during embryonic development. These two proto - oncogenes may play an important role in the

  15. Synonymous codon changes in the oncogenes of the cottontail rabbit papillomavirus lead to increased oncogenicity and immunogenicity of the virus

    Science.gov (United States)

    Cladel, Nancy M.; Budgeon, Lynn R.; Hu, Jiafen; Balogh, Karla K.; Christensen, Neil D.

    2013-01-01

    Papillomaviruses use rare codons with respect to the host. The reasons for this are incompletely understood but among the hypotheses is the concept that rare codons result in low protein production and this allows the virus to escape immune surveillance. We changed rare codons in the oncogenes E6 and E7 of the cottontail rabbit papillomavirus to make them more mammalian-like and tested the mutant genomes in our in vivo animal model. While the amino acid sequences of the proteins remained unchanged, the oncogenic potential of some of the altered genomes increased dramatically. In addition, increased immunogenicity, as measured by spontaneous regression, was observed as the numbers of codon changes increased. This work suggests that codon usage may modify protein production in ways that influence disease outcome and that evaluation of synonymous codons should be included in the analysis of genetic variants of infectious agents and their association with disease. PMID:23433866

  16. Can plant oncogenes inhibit programmed cell death? The rolB oncogene reduces apoptosis-like symptoms in transformed plant cells.

    Science.gov (United States)

    Gorpenchenko, Tatiana Y; Aminin, Dmitry L; Vereshchagina, Yuliya V; Shkryl, Yuri N; Veremeichik, Galina N; Tchernoded, Galina K; Bulgakov, Victor P

    2012-09-01

    The rolB oncogene was previously identified as an important player in ROS metabolism in transformed plant cells. Numerous reports indicate a crucial role for animal oncogenes in apoptotic cell death. Whether plant oncogenes such as rolB can induce programmed cell death (PCD) in transformed plant cells is of particular importance. In this investigation, we used a single-cell assay based on confocal microscopy and fluorescent dyes capable of discriminating between apoptotic and necrotic cells. Our results indicate that the expression of rolB in plant cells was sufficient to decrease the proportion of apoptotic cells in steady-state conditions and diminish the rate of apoptotic cells during induced PCD. These data suggest that plant oncogenes, like animal oncogenes, may be involved in the processes mediating PCD.

  17. In vivo study on the effects of microcystin extracts on the expression profiles of proto-oncogenes (c-fos, c-jun and c-myc) in liver, kidney and testis of male Wistar rats injected i.v. with toxins.

    Science.gov (United States)

    Li, Huiying; Xie, Ping; Li, Guangyu; Hao, Le; Xiong, Qian

    2009-01-01

    Microcystins (MCs) are a potent liver tumor promoter, possessing potent tumor-promoting activity and weak initiating activity. Proto-oncogenes are known to be involved in the tumor-promoting mechanisms of microcystin-LR. However, few data are available on the effects of MCs on proto-oncogenes in the whole animal. To investigate the effects of MCs on the expression profile of the proto-oncogenes in different organs, male Wistar rats were injected intravenously with microcystin extracts at a dose of 86.7 mug MC-LR eq/kg bw (MC-LR eq, MC-LR equivalents). mRNA levels of three proto-oncogenes c-fos, c-jun and c-myc in liver, kidney and testis were analyzed using quantitative real-time PCR at several time points post-injection. Significant induction of these genes at transcriptional level was observed in the three organs. In addition, the increase of mRNA expression of all three genes was much higher in liver than in kidney and testis. Meanwhile, the protein levels of c-Fos and c-Jun were investigated by western blotting. Both proteins were induced in the three organs. However, elevations of protein levels were much lower than those of mRNA levels. These findings suggest that the expression of c-fos, c-jun and c-myc might be one possible mechanism for the tumor-promoting activity and initiating activity of microcystins.

  18. Reference: MRNA3ENDTAH3 [PLACE

    Lifescience Database Archive (English)

    Full Text Available MRNA3ENDTAH3 Ohtsubo N, Iwabuchi M The conserved 3'-flanking sequence, AATGGAAATG, ...of the wheat histone H3 gene is necessary for the accurate 3'-end formation of mRNA. Nucleic Acids Res 22:1052-1058 (1994) PubMed: 8152910; ...

  19. Epithelial–mesenchymal transition during oncogenic transformation induced by hexavalent chromium involves reactive oxygen species-dependent mechanism in lung epithelial cells

    Energy Technology Data Exchange (ETDEWEB)

    Ding, Song-Ze, E-mail: dingsongze@hotmail.com [Department of Internal Medicine, Henan Provincial People’s Hospital, Zhengzhou University, Wei-Wu Road, Zhengzhou, Henan 450000 (China); Graduate Center for Toxicology, College of Medicine, University of Kentucky, Lexington, KY 40536 (United States); Yang, Yu-Xiu; Li, Xiu-Ling [Department of Internal Medicine, Henan Provincial People’s Hospital, Zhengzhou University, Wei-Wu Road, Zhengzhou, Henan 450000 (China); Michelli-Rivera, Audrey [Graduate Center for Toxicology, College of Medicine, University of Kentucky, Lexington, KY 40536 (United States); Han, Shuang-Yin [Department of Internal Medicine, Henan Provincial People’s Hospital, Zhengzhou University, Wei-Wu Road, Zhengzhou, Henan 450000 (China); Wang, Lei; Pratheeshkumar, Poyil; Wang, Xin; Lu, Jian; Yin, Yuan-Qin; Budhraja, Amit; Hitron, Andrew J. [Graduate Center for Toxicology, College of Medicine, University of Kentucky, Lexington, KY 40536 (United States)

    2013-05-15

    Hexavalent chromium [Cr(VI)] is an important human carcinogen associated with pulmonary diseases and lung cancer. Exposure to Cr(VI) induces DNA damage, cell morphological change and malignant transformation in human lung epithelial cells. Despite extensive studies, the molecular mechanisms remain elusive, it is also not known if Cr(VI)-induced transformation might accompany with invasive properties to facilitate metastasis. We aimed to study Cr(VI)-induced epithelial–mesenchymal transition (EMT) and invasion during oncogenic transformation in lung epithelial cells. The results showed that Cr(VI) at low doses represses E-cadherin mRNA and protein expression, enhances mesenchymal marker vimentin expression and transforms the epithelial cell into fibroblastoid morphology. Cr(VI) also increases cell invasion and promotes colony formation. Further studies indicated that Cr(VI) uses multiple mechanisms to repress E-cadherin expression, including activation of E-cadherin repressors such as Slug, ZEB1, KLF8 and enhancement the binding of HDAC1 in E-cadherin gene promoter, but DNA methylation is not responsible for the loss of E-cadherin. Catalase reduces Cr(VI)-induced E-cadherin and vimentin protein expression, attenuates cell invasion in matrigel and colony formation on soft agar. These results demonstrate that exposure to a common human carcinogen, Cr(VI), induces EMT and invasion during oncogenic transformation in lung epithelial cells and implicate in cancer metastasis and prevention. - Graphical abstract: Epithelial–mesenchymal transition during oncogenic transformation induced by hexavalent chromium involves reactive oxygen species-dependent mechanisms in lung epithelial cells. - Highlights: • We study if Cr(VI) might induce EMT and invasion in epithelial cells. • Cr(VI) induces EMT by altering E-cadherin and vimentin expression. • It also increases cell invasion and promotes oncogenic transformation. • Catalase reduces Cr(VI)-induced EMT, invasion and

  20. COX-2 Elevates Oncogenic miR-526b in Breast Cancer by EP4 Activation.

    Science.gov (United States)

    Majumder, Mousumi; Landman, Erin; Liu, Ling; Hess, David; Lala, Peeyush K

    2015-06-01

    MicroRNAs (miRs) are small regulatory molecules emerging as potential biomarkers in cancer. Previously, it was shown that COX-2 expression promotes breast cancer progression via multiple mechanisms, including induction of stem-like cells (SLC), owing to activation of the prostaglandin E2 receptor EP4 (PTGER4). COX-2 overexpression also upregulated microRNA-526b (miR-526b), in association with aggressive phenotype. Here, the functional roles of miR-526b in breast cancer and the mechanistic role of EP4 signaling in miR-526b upregulation were examined. A positive correlation was noted between miR-526b and COX-2 mRNA expression in COX-2 disparate breast cancer cell lines. Stable overexpression of miR-526b in poorly metastatic MCF7 and SKBR3 cell lines resulted in increased cellular migration, invasion, EMT phenotype and enhanced tumorsphere formation in vitro, and lung colony formation in vivo in immunodeficient mice. Conversely, knockdown of miR-526b in aggressive MCF7-COX-2 and SKBR3-COX-2 cells reduced oncogenic functions and reversed the EMT phenotype, in vitro. Furthermore, it was determined that miR-526b expression is dependent on EP4 receptor activity and downstream PI3K-AKT and cyclic AMP (cAMP) signaling pathways. PI3K-AKT inhibitors blocked EP4 agonist-mediated miR-526b upregulation and tumorsphere formation in MCF7 and SKBR3 cells. NF-κB inhibitor abrogates EP agonist-stimulated miRNA expression in MCF7 and T47D cells, indicating that the NF-κB pathway is also involved in miR-526b regulation. In addition, inhibition of COX-2, EP4, PI3K, and PKA in COX-2-overexpressing cells downregulated miR-526b and its functions in vitro. Finally, miR-526b expression was significantly higher in cancerous than in noncancerous breast tissues and associated with reduced patient survival. In conclusion, miR-526b promotes breast cancer progression, SLC-phenotype through EP4-mediated signaling, and correlates with breast cancer patient survival. This study presents novel

  1. MicroRNA-205 downregulates mixed-lineage-AF4 oncogene expression in acute lymphoblastic leukemia

    Directory of Open Access Journals (Sweden)

    Dou L

    2013-08-01

    Full Text Available Liping Dou,1,* Jingxin Li,1,* Dehua Zheng,2,* Yonghui Li,1 Xiaoning Gao,1 Chengwang Xu,1 Li Gao,1 Lili Wang,1 Li Yu1 1Department of Hematology, Chinese PLA General Hospital, Beijing, People's Republic of China; 2Department of Hepatobiliary Surgery, Organ Transplant Center, Chinese PLA 309th Hospital, Beijing, People's Republic of China*These authors contributed equally to this workAbstract: Myeloid/lymphoid or mixed-lineage AF4 acute lymphoblastic leukemia (MLL-AF4 ALL is a pediatric leukemia that occurs rarely in adults. MLL-AF4 ALL is typically characterized by the presence of chromosomal translocation (t(4;11(q21;q23, leading to expression of MLL-AF4 fusion protein. Although MLL-AF4 fusion protein triggers a molecular pathogenesis and hematological presentations that are unique to leukemias, the precise role of this oncogene in leukemogenesis remains unclear. Previous studies have indicated that microRNAs (miRs might modulate the expression of MLL-AF4 ALL fusion protein, thereby suggesting the involvement of miR in progression or suppression of MLL-AF4 ALL. We have previously demonstrated that miR-205 negatively regulates transcription of an MLL-AF4 luciferase reporter. Here, we report that exogenous expression of miR-205 in MLL-AF4 human cell lines (RS4;11 and MV4-11 inversely regulates the expression of MLL-AF4 at both messenger RNA (mRNA and protein level. Furthermore, miR-205 significantly induced apoptosis in MLL-AF4 cells as evidenced by Annexin V staining using fluorescence-activated cell sorting (FACS analysis. The proliferative capacity of leukemic cells was suppressed by miR-205. The addition of an miR-205 inhibitor was able to restore the observed effects. In conclusion, these findings demonstrate that miR-205 may have potential value as a novel therapeutic agent in the treatment of MLL-AF4 ALL.Keywords: miR-205, MLL-AF4, leukemia, microRNA, oncogene expression, untranslated regions, proliferation

  2. Oncogenic NRAS Primes Primary Acute Myeloid Leukemia Cells for Differentiation.

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    Cornelia Brendel

    Full Text Available RAS mutations are frequently found among acute myeloid leukemia patients (AML, generating a constitutively active signaling protein changing cellular proliferation, differentiation and apoptosis. We have previously shown that treatment of AML patients with high-dose cytarabine is preferentially beneficial for those harboring oncogenic RAS. On the basis of a murine AML cell culture model, we ascribed this effect to a RAS-driven, p53-dependent induction of differentiation. Hence, in this study we sought to confirm the correlation between RAS status and differentiation of primary blasts obtained from AML patients. The gene expression signature of AML blasts with oncogenic NRAS indeed corresponded to a more mature profile compared to blasts with wildtype RAS, as demonstrated by gene set enrichment analysis (GSEA and real-time PCR analysis of myeloid ecotropic viral integration site 1 homolog (MEIS1 in a unique cohort of AML patients. In addition, in vitro cell culture experiments with established cell lines and a second set of primary AML cells showed that oncogenic NRAS mutations predisposed cells to cytarabine (AraC driven differentiation. Taken together, our findings show that AML with inv(16 and NRAS mutation have a differentiation gene signature, supporting the notion that NRAS mutation may predispose leukemic cells to AraC induced differentiation. We therefore suggest that promotion of differentiation pathways by specific genetic alterations could explain the superior treatment outcome after therapy in some AML patient subgroups. Whether a differentiation gene expression status may generally predict for a superior treatment outcome in AML needs to be addressed in future studies.

  3. Systems perspectives on mRNA processing

    Institute of Scientific and Technical Information of China (English)

    Adrienne E McKee; Pamela A Silver

    2007-01-01

    The application of genomic technologies to the study of mRNA processing is increasingly conducted in metazoan organisms in order to understand the complex events that occur during and after transcription. Large-scale systems analyses of mRNA-protein interactions and mRNA dynamics have revealed specificity in mRNA transcription, splicing, transport, translation, and turnover, and have begun to make connections between the different layers of mRNA processing. Here, we review global studies of post-transcriptional processes and discuss the challenges facing our understanding of mRNA regulation in metazoan organisms. In parallel, we examine genome-scale investigations that have expanded our knowledge of RNA-binding proteins and the networks of mRNAs that they regulate.

  4. ERBB oncogene proteins as targets for monoclonal antibodies.

    Science.gov (United States)

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

    2012-03-01

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

  5. Three-Dimensional Mapping of mRNA Export through the Nuclear Pore Complex

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    Steven J. Schnell

    2014-11-01

    Full Text Available The locations of transcription and translation of mRNA in eukaryotic cells are spatially separated by the nuclear envelope (NE. Plenty of nuclear pore complexes (NPCs embedded in the NE function as the major gateway for the export of transcribed mRNAs from the nucleus to the cytoplasm. Whereas the NPC, perhaps one of the largest protein complexes, provides a relatively large channel for macromolecules to selectively pass through it in inherently three-dimensional (3D movements, this channel is nonetheless below the diffraction limit of conventional light microscopy. A full understanding of the mRNA export mechanism urgently requires real-time mapping of the 3D dynamics of mRNA in the NPC of live cells with innovative imaging techniques breaking the diffraction limit of conventional light microscopy. Recently, super-resolution fluorescence microscopy and single-particle tracking (SPT techniques have been applied to the study of nuclear export of mRNA in live cells. In this review, we emphasize the necessity of 3D mapping techniques in the study of mRNA export, briefly summarize the feasibility of current 3D imaging approaches, and highlight the new features of mRNA nuclear export elucidated with a newly developed 3D imaging approach combining SPT-based super-resolution imaging and 2D-to-3D deconvolution algorithms.

  6. [Roles of proto-oncogene c-erbB2 during the initiation growth of rat primordial follicles].

    Science.gov (United States)

    Huang, Jian; Zheng, Li-ping; Li, Fang; Wu, Lei; Xu, Liang-quan; Xu, Ai-xia; Pan, Xiao-ling; Zheng, Yue-hui

    2010-05-01

    To study the expression and possible roles of proto-oncogene c-erbB2 during the initiation growth of primordial follicles. Ovaries were collected from 2-day-old SD rats and cultured in the Waymouth culture system. In-situ hybridization, RT-PCR and immunohistochemistry were performed to assess the expressions of c-erbB2 mRNA and protein during the initiation growth of primordial follicles and after the effect of EGF. Western blot was used to observe the PCNA, p-ERK1/2 contents and correlation analysis was used to study the correlation relationship between contents of p-ERK1/2 and expressions of c-erbB2 mRNA at the same time of the primordial follicles growth. PCNA protein levels appeared to be more intense during the initiation growth of primordial follicles, EGF could promote the proliferation and differentiation of the primordial follicles. c-erbB2 mRNA existed in the oocytes endochylema and ErbB2 existed in the oocytes membrane, the expressions of c-erbB2 mRNA and ErbB2 appeared to be more intense when primordial follicles were cultured for 8 d than cultured for 0 d in the Waymouth culture system and were further increased with 50 ng/ml EGF for 4 d and 8 d. The same results were observed by RT-PCR, too. p-ERK1/2 protein levels were consistent with the changes of c-erbB2 mRNA and protein. Furthermore, Spearman rank correlation analysis showed there was a significant positive correlation relationship between the changes of p-ERK1/2 and the changes of c-erbB2 mRNA during the primordial follicles growth and after the effect of EGF (rs = 0.900, P primordial follicles with EGF, and it is indirectly suggested that c-erbB2 promotes the development of the primordial follicles via ERK-MAPK signal transduction.

  7. WWP1 as a potential tumor oncogene regulates PTEN-Akt signaling pathway in human gastric carcinoma.

    Science.gov (United States)

    Zhang, Li; Wu, Zongyin; Ma, Zhao; Liu, Hongtao; Wu, Yahong; Zhang, Qinxian

    2015-02-01

    Whelming evidence has demonstrated that WW domain containing E3 ubiquitin protein ligase 1 (WWP1) participates in a wide variety of biological processes and is tightly related to the initiation and progression of many tumors. Currently, although mounting evidence supports a role of WWP1 in tumor promotion and tumorigenesis, the potential roles of WWP1 and its biological functions in gastric carcinoma are not fully understood. Here, we found that WWP1 messenger RNA (mRNA) and protein were highly expressed in gastric carcinoma tissues and cells. High WWP1 mRNA and protein levels were tightly related to differentiation status, TNM stage, invasive depth, lymph node metastasis, and poor prognosis in gastric carcinoma. Furthermore, WWP1 siRNA significantly decreased WWP1 protein level in MKN-45 and AGS cells; meanwhile, WWP1 depletion markedly inhibited tumor proliferation in vitro and in vivo, arrested cell cycle at G0/G1 phase, and induced cell apoptosis in MKN-45 and AGS cells. Most notably, WWP1 downregulation both inactivated PTEN-Akt signaling pathway in MKN-45 and AGS cells. Taken altogether, our findings suggest that WWP1 acts as an oncogenic factor and should be considered as a novel interfering molecular target for gastric carcinoma.

  8. Genetic variations regulate alternative splicing in the 5' untranslated regions of the mouse glioma-associated oncogene 1, Gli1

    Directory of Open Access Journals (Sweden)

    Zaphiropoulos Peter G

    2010-04-01

    Full Text Available Abstract Background Alternative splicing is one of the key mechanisms that generate biological diversity. Even though alternative splicing also occurs in the 5' and 3' untranslated regions (UTRs of mRNAs, the understanding of the significance and the regulation of these variations is rather limited. Results We investigated 5' UTR mRNA variants of the mouse Gli1 oncogene, which is the terminal transcriptional effector of the Hedgehog (HH signaling pathway. In addition to identifying novel transcription start sites, we demonstrated that the expression ratio of the Gli1 splice variants in the 5' UTR is regulated by the genotype of the mouse strain analyzed. The GT allele, which contains the consensus intronic dinucleotides at the 5' splice site of intron 1B, favors exon 1B inclusion, while the GC allele, having a weaker 5' splice site sequence, promotes exon 1B skipping. Moreover, the alternative Gli1 5' UTRs had an impact on translational capacity, with the shorter and the exon 1B-skipped mRNA variants being most effective. Conclusions Our findings implicate novel, genome-based mechanisms as regulators of the terminal events in the mouse HH signaling cascade.

  9. BCL6 mRNA Expression Level in Invasive Duct Carcinoma not otherwise Specified

    Science.gov (United States)

    Badr, Eman; Masoud, Eman; Eldien, Marwa Serag

    2016-01-01

    Introduction B-Cell Lymphoma 6 (BCL6) has an oncogenic role in tumourigenesis of various malignancies. It represses genes involved in terminal differentiation and plays complementary role with Signal Transducer and Activator of Transcription 3 (STAT3) in triple-negative breast cancer cellular function. Aim To evaluate the expression of BCL6 in cancer breast and determine its correlation with the clinico-pathological features including the molecular subtype of breast carcinoma. Materials and Methods This prospective case control study was carried out on 150 patients, divided into 100 cases of invasive duct carcinoma not otherwise specified and 50 benign breast lesions including fibroadenoma and fibrocystic disease. Fresh tissues were excised, which were then subjected to RNA extraction. The BCL6 mRNA level was assessed using real-time reverse transcription Polymerase Chain Reaction (PCR). Results There was a significant higher levels of BCL6 mRNA in malignant cases compared to benign ones (p<0.001). The level of BCL6 mRNA was higher in cases showing advanced tumor stage (p<0.04), triple negative subtype and associated in situ component (p<0.001) compared to cases with an early stage, luminal or Her 2-neu positive subtypes and those lacking in situ component. Conclusion BCL6 is up-regulated in breast cancer and is associated with poor prognostic features such as advanced stage and triple negative molecular subtype. BCL6 inhibitors might be considered as targeted therapy for breast cancer. PMID:28208987

  10. Retroviruses hijack chromatin loops to drive oncogene expression and highlight the chromatin architecture around proto-oncogenic loci.

    Directory of Open Access Journals (Sweden)

    Jillian M Pattison

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

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

    Science.gov (United States)

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

    2015-01-01

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

  12. Production of mRNA cytokines in BALB/c mice infected with Paracoccidioides brasiliensis and analyses of the results by image processing; Producao de interleucinas RNAm em camundongos BALB/c infectados por Paracoccidioides brasiliensis, com analises dos resultados atraves de processamento de imagens

    Energy Technology Data Exchange (ETDEWEB)

    Januario, Adriana; Pietro, Rosemeire C.L. Rodrigues; Silva, Celio L. [Sao Paulo Univ., Ribeirao Preto, SP (Brazil). Faculdade de Medicina. Dept. de Parasitologia, Microbiologia e Imunologia; Rodrigues, Evandro L.L.; Franca, Celso A. de [Sao Paulo Univ., Sao Carlos, SP (Brazil). Escola de Engenharia. Dept. de Engenharia Eletrica

    1996-12-31

    The production of mRNA cytokines in BALB/c mice infected with Paracoccidioides brasiliensis is studied. It is reported that in the beginning of the disease with P. brasiliensis stimulated mice showed an analogous production between IL-2 and IL-10 mRNA, however, there is a predominance of IL-2 mRNA in the lung and of IL-10 mRNA in the liver cells. In this model, there is a dynamic change in the levels of IL-2 and IL-10 mRNA, suggesting the presence of both CD4+ T helper cells 7 refs., 6 figs.

  13. Visual detection of Akt mRNA in living cell using gold nanoparticle beacon

    Science.gov (United States)

    Ma, Yi; Tian, Caiping; Li, Siwen; Wang, Zhaohui; Gu, Yueqing

    2014-09-01

    PI3K-Akt signaling pathway plays the key role in cell apoptosis and survival, and the components of PI3K /Akt signaling pathway are often abnormally expressed in human tumors. Therefore, determination of the Akt (protein kinase B, PKB) messenger ribonucleic acid (mRNA) expression is significantly important in understanding the mechanism of tumor progression. In this study, we designed a special hairpin deoxyribonucleic acid (DNA) functionalized with gold nanoparticles and fluorescein isothiocyanate(FITC) as a beacon for detecting human Akt mRNA. Spectrofluorometer was used to detect the fluorescence quenching and recovery of the beacons, and laser confocal scanning microscopy was adopted to image Akt mRNA in cells. The results showed that this beacon could sensitively and quantitatively measure the Akt mRNA in living cells . This strategy is potentially useful for the cellular imaging of RNA or protein expression in living cells.

  14. Design of a small molecule against an oncogenic noncoding RNA.

    Science.gov (United States)

    Velagapudi, Sai Pradeep; Cameron, Michael D; Haga, Christopher L; Rosenberg, Laura H; Lafitte, Marie; Duckett, Derek R; Phinney, Donald G; Disney, Matthew D

    2016-05-24

    The design of precision, preclinical therapeutics from sequence is difficult, but advances in this area, particularly those focused on rational design, could quickly transform the sequence of disease-causing gene products into lead modalities. Herein, we describe the use of Inforna, a computational approach that enables the rational design of small molecules targeting RNA to quickly provide a potent modulator of oncogenic microRNA-96 (miR-96). We mined the secondary structure of primary microRNA-96 (pri-miR-96) hairpin precursor against a database of RNA motif-small molecule interactions, which identified modules that bound RNA motifs nearby and in the Drosha processing site. Precise linking of these modules together provided Targaprimir-96 (3), which selectively modulates miR-96 production in cancer cells and triggers apoptosis. Importantly, the compound is ineffective on healthy breast cells, and exogenous overexpression of pri-miR-96 reduced compound potency in breast cancer cells. Chemical Cross-Linking and Isolation by Pull-Down (Chem-CLIP), a small-molecule RNA target validation approach, shows that 3 directly engages pri-miR-96 in breast cancer cells. In vivo, 3 has a favorable pharmacokinetic profile and decreases tumor burden in a mouse model of triple-negative breast cancer. Thus, rational design can quickly produce precision, in vivo bioactive lead small molecules against hard-to-treat cancers by targeting oncogenic noncoding RNAs, advancing a disease-to-gene-to-drug paradigm.

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

    Science.gov (United States)

    Dominguez, Maria

    2014-04-01

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

  16. REST regulates oncogenic properties of glioblastoma stem cells

    Science.gov (United States)

    Kamal, Mohamed M.; Sathyan, Pratheesh; Singh, Sanjay K.; Zinn, Pascal O.; Marisetty, Anantha L.; Liang, Shoudan; Gumin, Joy; El-Mesallamy, Hala Osman; Suki, Dima; Colman, Howard; Fuller, Gregory N.; Lang, Frederick F.; Majumder, Sadhan

    2013-01-01

    Glioblastoma multiforme (GBM) tumors are the most common malignant primary brain tumors in adults. Although many GBM tumors are believed to be caused by self-renewing, glioblastoma-derived stem-like cells (GSCs), the mechanisms that regulate self-renewal and other oncogenic properties of GSCs are only now being unraveled. Here we showed that GSCs derived from GBM patient specimens express varying levels of the transcriptional repressor REST, suggesting heterogeneity across different GSC lines. Loss- and gain-of-function experiments indicated that REST maintains self-renewal of GSCs. High REST-expressing GSCs (HR-GSCs) produced tumors histopathologically distinct from those generated by low REST-expressing GSCs (LR-GSCs) in orthotopic mouse brain tumor models. Knockdown of REST in HR-GSCs resulted in increased survival in GSC-transplanted mice and produced tumors with higher apoptotic and lower invasive properties. Conversely, forced expression of exogenous REST in LR-GSCs produced decreased survival in mice and produced tumors with lower apoptotic and higher invasive properties, similar to HR-GSCs. Thus, based on our results, we propose that a novel function of REST is to maintain self-renewal and other oncogenic properties of GSCs and that REST can play a major role in mediating tumorigenicity in GBM. PMID:22228704

  17. Oncogenes Activate an Autonomous Transcriptional Regulatory Circuit That Drives Glioblastoma

    Directory of Open Access Journals (Sweden)

    Dinesh K. Singh

    2017-01-01

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

  18. Oncogenes Activate an Autonomous Transcriptional Regulatory Circuit That Drives Glioblastoma.

    Science.gov (United States)

    Singh, Dinesh K; Kollipara, Rahul K; Vemireddy, Vamsidara; Yang, Xiao-Li; Sun, Yuxiao; Regmi, Nanda; Klingler, Stefan; Hatanpaa, Kimmo J; Raisanen, Jack; Cho, Steve K; Sirasanagandla, Shyam; Nannepaga, Suraj; Piccirillo, Sara; Mashimo, Tomoyuki; Wang, Shan; Humphries, Caroline G; Mickey, Bruce; Maher, Elizabeth A; Zheng, Hongwu; Kim, Ryung S; Kittler, Ralf; Bachoo, Robert M

    2017-01-24

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

  19. Identification of polymorphisms and transcriptional activity of the proto-oncogene KIT located on both autosomal and B chromosomes of the Chinese raccoon dog.

    Science.gov (United States)

    Li, Y M; Zhang, Y; Zhu, W J; Yan, S Q; Sun, J H

    2016-02-05

    B chromosomes are dispensable and co-exist with autosomal and sex chromosomes. The karyotype of the Chinese raccoon dog (Nyctereutes procyonoides procyonoides) comprises 0-4 B chromosomes. The proto-oncogene KIT is found on all B chromosomes of the Chinese raccoon dog. In the present study, partial DNA and mRNA sequences of KIT were amplified and sequenced from four individuals containing B chromosomes. Sequence analyses revealed that polymorphisms including single nucleotide polymorphisms (SNPs) and inserts/deletions were rich in the KIT gene of Chinese raccoon dog at the genomic level. However, no polymorphism was detected at the mRNA level. A comparison of mRNA sequences from Chinese raccoon dogs with the corresponding sequences derived from arctic fox and dog, which do not contain B chromosomes, revealed the mRNA sequences of the 10 SNPs to be identical between these three species. Therefore, these findings suggest that KIT located on the B chromosomes in Chinese raccoon dog lacks transcriptional activity.

  20. Prediction of oncogenic interactions and cancer-related signaling networks based on network topology.

    Science.gov (United States)

    Acencio, Marcio Luis; Bovolenta, Luiz Augusto; Camilo, Esther; Lemke, Ney

    2013-01-01

    Cancer has been increasingly recognized as a systems biology disease since many investigators have demonstrated that this malignant phenotype emerges from abnormal protein-protein, regulatory and metabolic interactions induced by simultaneous structural and regulatory changes in multiple genes and pathways. Therefore, the identification of oncogenic interactions and cancer-related signaling networks is crucial for better understanding cancer. As experimental techniques for determining such interactions and signaling networks are labor-intensive and time-consuming, the development of a computational approach capable to accomplish this task would be of great value. For this purpose, we present here a novel computational approach based on network topology and machine learning capable to predict oncogenic interactions and extract relevant cancer-related signaling subnetworks from an integrated network of human genes interactions (INHGI). This approach, called graph2sig, is twofold: first, it assigns oncogenic scores to all interactions in the INHGI and then these oncogenic scores are used as edge weights to extract oncogenic signaling subnetworks from INHGI. Regarding the prediction of oncogenic interactions, we showed that graph2sig is able to recover 89% of known oncogenic interactions with a precision of 77%. Moreover, the interactions that received high oncogenic scores are enriched in genes for which mutations have been causally implicated in cancer. We also demonstrated that graph2sig is potentially useful in extracting oncogenic signaling subnetworks: more than 80% of constructed subnetworks contain more than 50% of original interactions in their corresponding oncogenic linear pathways present in the KEGG PATHWAY database. In addition, the potential oncogenic signaling subnetworks discovered by graph2sig are supported by experimental evidence. Taken together, these results suggest that graph2sig can be a useful tool for investigators involved in cancer research

  1. Prediction of oncogenic interactions and cancer-related signaling networks based on network topology.

    Directory of Open Access Journals (Sweden)

    Marcio Luis Acencio

    Full Text Available Cancer has been increasingly recognized as a systems biology disease since many investigators have demonstrated that this malignant phenotype emerges from abnormal protein-protein, regulatory and metabolic interactions induced by simultaneous structural and regulatory changes in multiple genes and pathways. Therefore, the identification of oncogenic interactions and cancer-related signaling networks is crucial for better understanding cancer. As experimental techniques for determining such interactions and signaling networks are labor-intensive and time-consuming, the development of a computational approach capable to accomplish this task would be of great value. For this purpose, we present here a novel computational approach based on network topology and machine learning capable to predict oncogenic interactions and extract relevant cancer-related signaling subnetworks from an integrated network of human genes interactions (INHGI. This approach, called graph2sig, is twofold: first, it assigns oncogenic scores to all interactions in the INHGI and then these oncogenic scores are used as edge weights to extract oncogenic signaling subnetworks from INHGI. Regarding the prediction of oncogenic interactions, we showed that graph2sig is able to recover 89% of known oncogenic interactions with a precision of 77%. Moreover, the interactions that received high oncogenic scores are enriched in genes for which mutations have been causally implicated in cancer. We also demonstrated that graph2sig is potentially useful in extracting oncogenic signaling subnetworks: more than 80% of constructed subnetworks contain more than 50% of original interactions in their corresponding oncogenic linear pathways present in the KEGG PATHWAY database. In addition, the potential oncogenic signaling subnetworks discovered by graph2sig are supported by experimental evidence. Taken together, these results suggest that graph2sig can be a useful tool for investigators involved

  2. [Nature of cancer explored from the perspective of the functional evolution of proto-oncogenes].

    Science.gov (United States)

    Watari, Akihiro

    2012-01-01

    The products of proto-oncogene play critical roles in the development or maintenance of multicellular societies in animals via strict regulatory systems. When these regulatory systems are disrupted, proto-oncogenes can become oncogenes, and thereby induce cell transformation and carcinogenesis. To understand the molecular basis for development of the regulatory system of proto-oncogenes during evolution, we screened for ancestral proto-oncogenes from the unicellular choanoflagellate Monosiga ovata (M. ovata) by monitoring their transforming ability in mammalian cells; consequently, we isolated a Pak gene ortholog, which encodes a serine/threonine kinase as a 'primitive oncogene'. We also cloned Pak orthologs from fungi and the multicellular sponge Ephydatia fluviatilis, and compared their regulatory features with that of M. ovata Pak (MoPak). MoPak is constitutively active and induces cell transformation in mammalian cells. In contrast, Pak orthologs from multicellular animals are strictly regulated. Analyses of Pak mutants revealed that structural alterations in the auto-inhibitory domain (AID) are responsible for the enhanced kinase activity and the oncogenic activity of MoPak. Furthermore, we show that Rho family GTPases-mediated regulatory system of Pak kinase is conserved throughout the evolution from unicellular to multicellular animals, but the MoPak is more sensitive to the Rho family GTPases-mediated activation than multicellular Pak. These results show that maturation of AID function was required for the development of the strict regulatory system of the Pak proto-oncogene, and support the potential link between the development of the regulatory system of proto-oncogenes and the evolution of multicellularity. Further analysis of oncogenic functions of proto-oncogene orthologs in the unicellular genes would provide some insights into the mechanisms of the destruction of multicellular society in cancer.

  3. Functional Analysis of the Proto-oncogenes Septin9 and Nras

    DEFF Research Database (Denmark)

    Lassen, Louise Berkhoudt

    regardless of genotype indicating an oncogenic role of SEPT9. Nras is a potent proto-oncogene involved in signaling through a number of proliferative pathways. Earlier detected retroviral integration sites resulting in B-cell lymphomas were used to create Nras knock in models harboring the LTR from...

  4. Functional polymorphism of the CK2alpha intronless gene plays oncogenic roles in lung cancer.

    Directory of Open Access Journals (Sweden)

    Ming-Szu Hung

    Full Text Available Protein kinase CK2 is frequently up-regulated in human cancers, although the mechanism of CK2 activation in cancer remains unknown. In this study, we investigated the role of the CK2alpha intronless gene (CSNK2A1P, a presumed CK2alpha pseudogene in the pathogenesis of human cancers. We found evidence of amplification and over-expression of the CSNK2A1P gene in non-small cell lung cancer and leukemia cell lines and 25% of the lung cancer tissues studied. The mRNA expression levels correlated with the copy numbers of the CSNK2A1P gene. We also identified a novel polymorphic variant (398T/C, I133T of the CSNK2A1P gene and showed that the 398T allele is selectively amplified over the 398C allele in 101 non-small cell lung cancer tissue samples compared to those in 48 normal controls (p = 0.013<0.05. We show for the first time CSNK2A1P protein expression in transfected human embryonic kidney 293T and mouse embryonic fibroblast NIH-3T3 cell lines. Both alleles are transforming in these cell lines, and the 398T allele appears to be more transforming than the 398C allele. Moreover, the 398T allele degrades PML tumor suppressor protein more efficiently than the 398C allele and shows a relatively stronger binding to PML. Knockdown of the CSNK2A1P gene expression with specific siRNA increased the PML protein level in lung cancer cells. We report, for the first time, that the CSNK2A1P gene is a functional proto-oncogene in human cancers and its functional polymorphism appears to degrade PML differentially in cancer cells. These results are consistent with an important role for the 398T allele of the CSNK2A1P in human lung cancer susceptibility.

  5. Electrochemical detection of leukemia oncogenes using enzyme-loaded carbon nanotube labels

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Ai Cheng; Du, Dan; Chen, Baowei; Heng, Chew-Kiat; Lim, Tit-Meng; Lin, Yuehe

    2014-09-07

    Here we describe an ultrasensitive electrochemical nucleic acids assay amplified by carbon nanotubes (CNTs)-based labels for the detection of human acute lymphocytic leukemia (ALL) related p185 BCR-ABL fusion transcript. The carboxylated CNTs were functionalized with horseradish peroxidase (HRP) molecules and target-specific detection probes (DP) via diimide-activated amidation, and used to label and amplify target hybridization signal. The activity of captured HRP was monitored by square-wave voltammetry measuring the electroactive enzymatic product in the presence of 2-aminophenol and hydrogen peroxide substrate solution. The effect of DP and HRP loading of the CNT-based labels on its signal-to-noise ratio of electrochemical detection was studied systematically for the first time. Under optimized conditions, the signal-amplified assay achieved a detection limit of 83 fM targets oligonuecleotides and a 4-order wide dynamic range of target concentration. The resulting assay allowed a robust discrimination between the perfect match and a three-base mismatch sequence. When subjected to full-length (491 bp) DNA oncogene, the approach demonstrated a detection limit of approximately 33 pg of the target gene. The high sensitivity and specificity of assay enabled PCR-free detection of target transcripts in as little as 65 ng of mRNA extracted from positive ALL cell lines SUP-B15, in comparison to those obtained from negative cell lines HL-60. The approach holds promise for simple, low cost and ultrasensitive electrochemical nucleic acids detection in portable devices, point-of-care and early disease diagnostic applications.

  6. RET oncogene in MEN2, MEN2B, MTC and other forms of thyroid cancer.

    Science.gov (United States)

    Lodish, Maya B; Stratakis, Constantine A

    2008-04-01

    Hereditary medullary thyroid carcinoma (MTC) is caused by specific autosomal dominant gain-of-function mutations in the RET proto-oncogene. Genotype-phenotype correlations exist that help predict the presence of other associated endocrine neoplasms as well as the timing of thyroid cancer development. MTC represents a promising model for targeted cancer therapy, as the oncogenic event responsible for initiating malignancy has been well characterized. The RET proto-oncogene has become the target for molecularly designed drug therapy. Tyrosine kinase inhibitors targeting activated RET are currently in clinical trials for the treatment of patients with MTC. This review will provide a brief overview of MTC and the associated RET oncogenic mutations, and will summarize the therapies designed to strategically interfere with the pathologic activation of the RET oncogene.

  7. A comprehensive characterization of genome-wide copy number aberrations in colorectal cancer reveals novel oncogenes and patterns of alterations.

    Directory of Open Access Journals (Sweden)

    Tao Xie

    Full Text Available To develop a comprehensive overview of copy number aberrations (CNAs in stage-II/III colorectal cancer (CRC, we characterized 302 tumors from the PETACC-3 clinical trial. Microsatellite-stable (MSS samples (n = 269 had 66 minimal common CNA regions, with frequent gains on 20 q (72.5%, 7 (41.8%, 8 q (33.1% and 13 q (51.0% and losses on 18 (58.6%, 4 q (26% and 21 q (21.6%. MSS tumors have significantly more CNAs than microsatellite-instable (MSI tumors: within the MSI tumors a novel deletion of the tumor suppressor WWOX at 16 q23.1 was identified (p<0.01. Focal aberrations identified by the GISTIC method confirmed amplifications of oncogenes including EGFR, ERBB2, CCND1, MET, and MYC, and deletions of tumor suppressors including TP53, APC, and SMAD4, and gene expression was highly concordant with copy number aberration for these genes. Novel amplicons included putative oncogenes such as WNK1 and HNF4A, which also showed high concordance between copy number and expression. Survival analysis associated a specific patient segment featured by chromosome 20 q gains to an improved overall survival, which might be due to higher expression of genes such as EEF1B2 and PTK6. The CNA clustering also grouped tumors characterized by a poor prognosis BRAF-mutant-like signature derived from mRNA data from this cohort. We further revealed non-random correlation between CNAs among unlinked loci, including positive correlation between 20 q gain and 8 q gain, and 20 q gain and chromosome 18 loss, consistent with co-selection of these CNAs. These results reinforce the non-random nature of somatic CNAs in stage-II/III CRC and highlight loci and genes that may play an important role in driving the development and outcome of this disease.

  8. Down-regulation of the oncogene PTTG1 via the KLF6 tumor suppressor during induction of myeloid differentiation.

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    Pei-Yi Chen

    Full Text Available The aberrant expression of proto-oncogenes is involved in processes that are responsible for cellular proliferation and the inhibition of myeloid differentiation in acute myeloid leukemia (AML. Pituitary Tumor-Transforming gene 1 (PTTG1, an oncogenic transcription factor, is abundantly expressed in various human cancers and hematopoietic malignancies. However, its expression in normal leukocytes and most normal tissues is very low or undetectable. The mechanism by which PTTG1 overexpression modifies myeloid cell development and promotes leukemogenesis remain unclear. To investigate the mechanistic links between PTTG1 overexpression and leukemia cell differentiation, we utilized phorbol 12-myristate 13-acetate (PMA, a well-known agent that triggers monocyte/macrophage differentiation, to analyze the expression patterns of PTTG1 in PMA-induced myeloid differentiation. We found that PTTG1 is down-regulated at the transcriptional level in PMA-treated HL-60 and THP1 cells. In addition, we identified a binding site for a tumor suppressor protein, Kruppel-like factor 6 (KLF6, in the PTTG1 promoter. We found that KLF6 could directly bind and repress PTTG1 expression. In HL-60 and THP1 cells, KLF6 mRNA and protein levels are up-regulated with a concordant reduction of PTTG1 expression upon treatment with PMA. Furthermore, KLF6 knockdown by shRNA abolished the suppression of PTTG1 and reduced the activation of the differentiation marker CD11b in PMA-primed cells. The protein kinase C (PKC inhibitor and the MAPK/ERK kinase (MEK inhibitor significantly blocked the potentiation of PMA-mediated KLF6 induction and the down-regulation of PTTG1, indicating that PTTG1 is suppressed via the activation of PKC/ERK/KLF6 pathway. Our findings suggest that drugs that increase the KLF6 inhibition of PTTG1 may have a therapeutic application in AML treatment strategies.

  9. [Connection of magnetic antisense probe with SK-Br-3 oncocyte mRNA nucleotide detected by high resolution atomic force microscope].

    Science.gov (United States)

    Tan, Shude; Ouyang, Yu; Li, Xinyou; Wen, Ming; Li, Shaolin

    2011-06-01

    The present paper is aimed to detect superparamagnetic iron oxide labeled c-erbB2 oncogene antisense oligonucleotide probe (magnetic antisense probe) connected with SK-Br-3 oncocyte mRNA nucleotide by high resolution atomic force microscope (AFM). We transfected SK-Br-3 oncocyte with magnetic antisense probe, then observed the cells by AFM with high resolution and detected protein expression and magnetic resonance imagine (MRI). The high resolution AFM clearly showed the connection of the oligonucleotide remote end of magnetic antisense probe with the mRNA nucleotide of oncocyte. The expression of e-erbB2 protein in SK-Br3 cells were highly inhibited by using magnetic antisense probe. We then obtained the lowest signal to noise ratio (SNR) of SK-Br-3 oncocyte transfected with magnetic antisense probe by MRI (PSK-Br-3 mRNA of tumor cell nuclear.

  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. Mutations of the KRAS oncogene in endometrial hyperplasia and carcinoma.

    Directory of Open Access Journals (Sweden)

    Wiesława Niklińska

    2009-05-01

    Full Text Available The aim of this study was to examine the prevalence and clinicopathological significance of KRAS point mutation in endometrial hyperplasia and carcinoma. We analysed KRAS in 11 cases of complex atypical hyperplasia and in 49 endometrial carcinomas using polymerase chain reaction associated with restriction fragment length polymorphism (PCR-RFPL. Point mutations at codon 12 of KRAS oncogene were identified in 7 of 49 (14,3% tumor specimens and in 2 of 11 (18,2% hyperplasias. No correlation was found between KRAS gene mutation and age at onset, histology, grade of differentiation and clinical stage. We conclude that KRAS mutation is a relatively common event in endometrial carcinogenesis, but with no prognostic value.

  12. Structural Effects of Oncogenic PI3K alpha Mutations

    Energy Technology Data Exchange (ETDEWEB)

    S Gabelli; C Huang; D Mandelker; O Schmidt-Kittler; B Vogelstein; L Amzel

    2011-12-31

    Physiological activation of PI3K{alpha} is brought about by the release of the inhibition by p85 when the nSH2 binds the phosphorylated tyrosine of activated receptors or their substrates. Oncogenic mutations of PI3K{alpha} result in a constitutively activated enzyme that triggers downstream pathways that increase tumor aggressiveness and survival. Structural information suggests that some mutations also activate the enzyme by releasing p85 inhibition. Other mutations work by different mechanisms. For example, the most common mutation, His1047Arg, causes a conformational change that increases membrane association resulting in greater accessibility to the substrate, an integral membrane component. These effects are examples of the subtle structural changes that result in increased activity. The structures of these and other mutants are providing the basis for the design of isozyme-specific, mutation-specific inhibitors for individualized cancer therapies.

  13. Oncogenes, protooncogenes, and tumor suppressor genes in acute myelogenous leukemia.

    Science.gov (United States)

    Hijiya, N; Gewirtz, A M

    1995-05-01

    In recent years, our understanding of normal human hematopoiesis has expanded greatly. We have increased our knowledge of regulatory growth factors, the receptors through which they act, and the secondary messengers involved in transducing the growth/differentiation signals from the cytoplasmic membrane to the nucleus. This knowledge has revealed potential mechanisms for inducing the neoplastic transformation of hematopoietic cells. This applies in particular to the role of viral oncogenes and cellular protooncogenes and, more recently, to the role of tumor suppressor genes. Protooncogenes are intimately involved in the processes of cell proliferation and differentiation. Therefore, any amplification, mutation, structural alteration, or change in transcriptional regulation of protooncogenes might lead to or be associated with induction of the malignant phenotype. Based on the importance of these genes in leukemogenesis and the maintenance of the malignant phenotype, it seems reasonable to hypothesize that targeted disruption of leukemogenic genes may be of therapeutic value.

  14. Terminal and progenitor lineage-survival oncogenes as cancer markers.

    Science.gov (United States)

    Vias, Maria; Ramos-Montoya, Antonio; Mills, Ian G

    2008-11-01

    Tumour classification has traditionally focused on differentiation and cellular morphology, and latterly on the application of genomic approaches. By combining chromatin immunoprecipitation with expression array, it has been possible to identify direct gene targets for transcription factors for nuclear hormone receptors. At the same time, there have been great strides in deriving stem and progenitor cells from tissues. It is therefore timely to propose that pairing the isolation of these cell subpopulations from tissues and tumours with these genomics approaches will reveal conserved gene targets for transcription factors. By focusing on transcription factors (lineage-survival oncogenes) with roles in both organogenesis and tumourigenesis at multiple organ sites, we suggest that this comparative genomics approach will enable developmental biology to be used more fully in relation to understanding tumour progression and will reveal new cancer markers. We focus here on neurogenesis and neuroendocrine differentiation in tumours.

  15. Use of glycolytic pathways for inhibiting or measuring oncogenic signaling

    Energy Technology Data Exchange (ETDEWEB)

    Onodera, Yasuhito; Bissell, Mina

    2017-06-27

    Disclosed are methods in which glucose metabolism is correlated to oncogenesis through certain specific pathways; inhibition of certain enzymes is shown to interfere with oncogenic signaling, and measurement of certain enzyme levels is correlated with patient survival. The present methods comprise measuring level of expression of at least one of the enzymes involved in glucose uptake or metabolism, wherein increased expression of the at least one of the enzymes relative to expression in a normal cell correlates with poor prognosis of disease in a patient. Preferably the genes whose expression level is measured include GLUT3, PFKP, GAPDH, ALDOC, LDHA and GFPT2. Also disclosed are embodiments directed towards downregulating the expression of some genes in glucose uptake and metabolism.

  16. Tumor-derived exosomes in oncogenic reprogramming and cancer progression.

    Science.gov (United States)

    Saleem, Sarmad N; Abdel-Mageed, Asim B

    2015-01-01

    In multicellular organisms, effective communication between cells is a crucial part of cellular and tissue homeostasis. This communication mainly involves direct cell-cell contact as well as the secretion of molecules that bind to receptors at the recipient cells. However, a more recently characterized mode of intercellular communication-the release of membrane vesicles known as exosomes-has been the subject of increasing interest and intensive research over the past decade. Following the discovery of the exosome-mediated immune activation, the pathophysiological roles of exosomes have been recognized in different diseases, including cancer. In this review, we describe the biogenesis and main physical characteristics that define exosomes as a specific population of secreted vesicles, with a special focus on their role in oncogenic transformation and cancer progression.

  17. Structural effects of oncogenic PI3Kα mutations.

    Science.gov (United States)

    Gabelli, Sandra B; Huang, Chuan-Hsiang; Mandelker, Diana; Schmidt-Kittler, Oleg; Vogelstein, Bert; Amzel, L Mario

    2010-01-01

    Physiological activation of PI3Kα is brought about by the release of the inhibition by p85 when the nSH2 binds the phosphorylated tyrosine of activated receptors or their substrates. Oncogenic mutations of PI3Kα result in a constitutively activated enzyme that triggers downstream pathways that increase tumor aggressiveness and survival. Structural information suggests that some mutations also activate the enzyme by releasing p85 inhibition. Other mutations work by different mechanisms. For example, the most common mutation, His1047Arg, causes a conformational change that increases membrane association resulting in greater accessibility to the substrate, an integral membrane component. These effects are examples of the subtle structural changes that result in increased activity. The structures of these and other mutants are providing the basis for the design of isozyme-specific, mutation-specific inhibitors for individualized cancer therapies.

  18. Intrinsic structural disorder confers cellular viability on oncogenic fusion proteins.

    Directory of Open Access Journals (Sweden)

    Hedi Hegyi

    2009-10-01

    Full Text Available Chromosomal translocations, which often generate chimeric proteins by fusing segments of two distinct genes, represent the single major genetic aberration leading to cancer. We suggest that the unifying theme of these events is a high level of intrinsic structural disorder, enabling fusion proteins to evade cellular surveillance mechanisms that eliminate misfolded proteins. Predictions in 406 translocation-related human proteins show that they are significantly enriched in disorder (43.3% vs. 20.7% in all human proteins, they have fewer Pfam domains, and their translocation breakpoints tend to avoid domain splitting. The vicinity of the breakpoint is significantly more disordered than the rest of these already highly disordered fusion proteins. In the unlikely event of domain splitting in fusion it usually spares much of the domain or splits at locations where the newly exposed hydrophobic surface area approximates that of an intact domain. The mechanisms of action of fusion proteins suggest that in most cases their structural disorder is also essential to the acquired oncogenic function, enabling the long-range structural communication of remote binding and/or catalytic elements. In this respect, there are three major mechanisms that contribute to generating an oncogenic signal: (i a phosphorylation site and a tyrosine-kinase domain are fused, and structural disorder of the intervening region enables intramolecular phosphorylation (e.g., BCR-ABL; (ii a dimerisation domain fuses with a tyrosine kinase domain and disorder enables the two subunits within the homodimer to engage in permanent intermolecular phosphorylations (e.g., TFG-ALK; (iii the fusion of a DNA-binding element to a transactivator domain results in an aberrant transcription factor that causes severe misregulation of transcription (e.g. EWS-ATF. Our findings also suggest novel strategies of intervention against the ensuing neoplastic transformations.

  19. Deciphering hepatocellular responses to metabolic and oncogenic stress

    Directory of Open Access Journals (Sweden)

    Kathrina L. Marcelo

    2015-08-01

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

  20. DNA topoisomerases participate in fragility of the oncogene RET.

    Directory of Open Access Journals (Sweden)

    Laura W Dillon

    Full Text Available Fragile site breakage was previously shown to result in rearrangement of the RET oncogene, resembling the rearrangements found in thyroid cancer. Common fragile sites are specific regions of the genome with a high susceptibility to DNA breakage under conditions that partially inhibit DNA replication, and often coincide with genes deleted, amplified, or rearranged in cancer. While a substantial amount of work has been performed investigating DNA repair and cell cycle checkpoint proteins vital for maintaining stability at fragile sites, little is known about the initial events leading to DNA breakage at these sites. The purpose of this study was to investigate these initial events through the detection of aphidicolin (APH-induced DNA breakage within the RET oncogene, in which 144 APH-induced DNA breakpoints were mapped on the nucleotide level in human thyroid cells within intron 11 of RET, the breakpoint cluster region found in patients. These breakpoints were located at or near DNA topoisomerase I and/or II predicted cleavage sites, as well as at DNA secondary structural features recognized and preferentially cleaved by DNA topoisomerases I and II. Co-treatment of thyroid cells with APH and the topoisomerase catalytic inhibitors, betulinic acid and merbarone, significantly decreased APH-induced fragile site breakage within RET intron 11 and within the common fragile site FRA3B. These data demonstrate that DNA topoisomerases I and II are involved in initiating APH-induced common fragile site breakage at RET, and may engage the recognition of DNA secondary structures formed during perturbed DNA replication.

  1. [Imaging].

    Science.gov (United States)

    Chevrot, A; Drapé, J L; Godefroy, D; Dupont, A M; Pessis, E; Sarazin, L; Minoui, A

    1997-01-01

    The panoply of imaging techniques useful in podology is essentially limited to X-rays. Standard "standing" and "lying" X-rays furnish most of the required information. Arthrography is sometimes performed, in particular for trauma or tumour of the ankle. CT scan and MRI make a decisive contribution in difficult cases, notably in fractures and in small fractures without displacement. The two latter techniques are useful in tendon, ligament and muscular disorders, where echography is also informative. Rigorous analysis of radiographies and a good knowledge of foot disorders make these imaging techniques efficacious.

  2. LIN28 expression in malignant germ cell tumors down-regulates let-7 and increases oncogene levels

    Science.gov (United States)

    Murray, Matthew J.; Saini, Harpreet K.; Siegler, Charlotte A.; Hanning, Jennifer E.; Barker, Emily M.; van Dongen, Stijn; Ward, Dawn M.; Raby, Katie L.; Groves, Ian J.; Scarpini, Cinzia G.; Pett, Mark R.; Thornton, Claire M.; Enright, Anton J.; Nicholson, James C.; Coleman, Nicholas

    2013-01-01

    Despite their clinico-pathologic heterogeneity, malignant germ-cell-tumors (GCTs) share molecular abnormalities that are likely to be functionally important. In this study, we investigated the potential significance of down-regulation of the let-7 family of tumor-suppressor microRNAs in malignant-GCTs. Microarray results from pediatric and adult samples (n=45) showed that LIN28, the negative-regulator of let-7 biogenesis, was abundant in malignant-GCTs, regardless of patient age, tumor site or histologic subtype. Indeed, a strong negative-correlation existed between LIN28 and let-7 levels in specimens with matched datasets. Low let-7 levels were biologically significant, since the sequence complementary to the 2-7nt common let-7 seed ‘GAGGUA’ was enriched in the 3′untranslated regions of mRNAs up-regulated in pediatric and adult malignant-GCTs, compared with normal gonads (a mixture of germ cells and somatic cells). We identified 27 mRNA targets of let-7 that were up-regulated in malignant-GCT cells, confirming significant negative-correlations with let-7 levels. Among 16 mRNAs examined in a largely independent set of specimens by qRT-PCR, we defined negative-associations with let-7e levels for six oncogenes, including MYCN, AURKB, CCNF, RRM2, MKI67 and C12orf5 (when including normal control tissues). Importantly, LIN28 depletion in malignant-GCT cells restored let-7 levels and repressed all of these oncogenic let-7 mRNA targets, with LIN28 levels correlating with cell proliferation and MYCN levels. Conversely, ectopic expression of let-7e was sufficient to reduce proliferation and down-regulate MYCN, AURKB and LIN28, the latter via a double-negative feedback loop. We concluded that the LIN28/let-7 pathway has a critical pathobiological role in malignant-GCTs and therefore offers a promising target for therapeutic intervention. PMID:23774216

  3. Mapping interactions between mRNA export factors in living cells.

    Directory of Open Access Journals (Sweden)

    I-Fang Teng

    Full Text Available The TREX complex couples nuclear mRNA processing events with subsequent export to the cytoplasm. TREX also acts as a binding platform for the mRNA export receptor Nxf1. The sites of mRNA transcription and processing within the nucleus have been studied extensively. However, little is known about where TREX assembly takes place and where Nxf1 is recruited to TREX to form the export competent mRNP. Here we have used sensitized emission Förster resonance energy transfer (FRET and fluorescence lifetime imaging (FLIM-FRET, to produce a spatial map in living cells of the sites for the interaction of two TREX subunits, Alyref and Chtop, with Nxf1. Prominent assembly sites for export factors are found in the vicinity of nuclear speckles in regions known to be involved in transcription, splicing and exon junction complex formation highlighting the close coupling of mRNA export with mRNP biogenesis.

  4. Functional transition of Pak proto-oncogene during early evolution of metazoans.

    Science.gov (United States)

    Watari, A; Iwabe, N; Masuda, H; Okada, M

    2010-07-01

    Proto-oncogenes encode signaling molecular switches regulating cellular homeostasis in metazoans, and can be converted to oncogenes by gain-of-function mutations. To address the molecular basis for development of the regulatory system of proto-oncogenes during evolution, we screened for ancestral proto-oncogenes from the unicellular choanoflagellate Monosiga ovata by monitoring their transforming activities, and isolated a Pak gene ortholog encoding a serine/threonine kinase as a 'primitive oncogene'. We also cloned Pak orthologs from fungi and the multicellular sponge Ephydatia fluviatilis, and compared their regulatory features with that of M. ovata Pak (MoPak). MoPak is constitutively active and induces cell transformation in mammalian fibroblasts, although the Pak orthologs from multicellular animals are strictly regulated. Analyses of Pak mutants revealed that structural alteration of the auto-inhibitory domain (AID) of MoPak confers higher constitutive kinase activity, as well as greater binding ability to Rho family GTPases than the multicellular Paks, and this structural alteration is responsible for cell transformation and disruption of multicellular tissue organization. These results show that maturation of AID function was required for the development of the strict regulatory system of the Pak proto-oncogene, and suggest a potential link between the establishment of the regulatory system of proto-oncogenes and metazoan evolution.

  5. Tracking single mRNA molecules in live cells

    Science.gov (United States)

    Moon, Hyungseok C.; Lee, Byung Hun; Lim, Kiseong; Son, Jae Seok; Song, Minho S.; Park, Hye Yoon

    2016-06-01

    mRNAs inside cells interact with numerous RNA-binding proteins, microRNAs, and ribosomes that together compose a highly heterogeneous population of messenger ribonucleoprotein (mRNP) particles. Perhaps one of the best ways to investigate the complex regulation of mRNA is to observe individual molecules. Single molecule imaging allows the collection of quantitative and statistical data on subpopulations and transient states that are otherwise obscured by ensemble averaging. In addition, single particle tracking reveals the sequence of events that occur in the formation and remodeling of mRNPs in real time. Here, we review the current state-of-the-art techniques in tagging, delivery, and imaging to track single mRNAs in live cells. We also discuss how these techniques are applied to extract dynamic information on the transcription, transport, localization, and translation of mRNAs. These studies demonstrate how single molecule tracking is transforming the understanding of mRNA regulation in live cells.

  6. Self-amplifying mRNA vaccines.

    Science.gov (United States)

    Brito, Luis A; Kommareddy, Sushma; Maione, Domenico; Uematsu, Yasushi; Giovani, Cinzia; Berlanda Scorza, Francesco; Otten, Gillis R; Yu, Dong; Mandl, Christian W; Mason, Peter W; Dormitzer, Philip R; Ulmer, Jeffrey B; Geall, Andrew J

    2015-01-01

    This chapter provides a brief introduction to nucleic acid-based vaccines and recent research in developing self-amplifying mRNA vaccines. These vaccines promise the flexibility of plasmid DNA vaccines with enhanced immunogenicity and safety. The key to realizing the full potential of these vaccines is efficient delivery of nucleic acid to the cytoplasm of a cell, where it can amplify and express the encoded antigenic protein. The hydrophilicity and strong net negative charge of RNA impedes cellular uptake. To overcome this limitation, electrostatic complexation with cationic lipids or polymers and physical delivery using electroporation or ballistic particles to improve cellular uptake has been evaluated. This chapter highlights the rapid progress made in using nonviral delivery systems for RNA-based vaccines. Initial preclinical testing of self-amplifying mRNA vaccines has shown nonviral delivery to be capable of producing potent and robust innate and adaptive immune responses in small animals and nonhuman primates. Historically, the prospect of developing mRNA vaccines was uncertain due to concerns of mRNA instability and the feasibility of large-scale manufacturing. Today, these issues are no longer perceived as barriers in the widespread implementation of the technology. Currently, nonamplifying mRNA vaccines are under investigation in human clinical trials and can be produced at a sufficient quantity and quality to meet regulatory requirements. If the encouraging preclinical data with self-amplifying mRNA vaccines are matched by equivalently positive immunogenicity, potency, and tolerability in human trials, this platform could establish nucleic acid vaccines as a versatile new tool for human immunization. Copyright © 2015 Elsevier Inc. All rights reserved.

  7. MiR-506 suppresses liver cancer angiogenesis through targeting sphingosine kinase 1 (SPHK1) mRNA.

    Science.gov (United States)

    Lu, Zhanping; Zhang, Weiying; Gao, Shan; Jiang, Qiulei; Xiao, Zelin; Ye, Lihong; Zhang, Xiaodong

    MicroRNAs acting as oncogenes or tumor suppressor genes play crucial roles in human cancers. Sphingosine kinase 1 (SPHK1) and its metabolite sphingosine 1-phosphate (S1P) contribute to tumor angiogenesis. We have reported that the down-regulation of miR-506 targeting YAP mRNA results in the hepatocarcinogenesis. In the present study, we report a novel function of miR-506, which suppresses tumor angiogenesis through targeting SPHK1 mRNA in liver cancer. Bioinformatics analysis showed that miR-506 might target 3'-untranslated region (3'UTR) of SPHK1 mRNA. Then, we validated that by luciferase reporter gene assays. MiR-506 was able to reduce the expression of SPHK1 at the levels of mRNA and protein using reverse transcription-polymerase chain reaction and Western blot analysis in hepatoma HepG2 cells. Functionally, human umbilical vein endothelial cell (HUVEC) tube formation assays demonstrated that the forced miR-506 expression remarkably inhibited the production of S1P in the supernatant of hepatoma cells. The supernatant resulted in the inhibition of tumor angiogenesis. Interestingly, the supernatant with overexpression of SPHK1 could rescue the inhibition of angiogenesis of liver cancer mediated by miR-506. Anti-miR-506 increased the production of S1P in the supernatant of hepatoma cells, but the supernatant with silencing of SPHK1 abolished anti-miR-506-induced acceleration of tumor angiogenesis. Clinically, we observed that the levels of miR-506 were negatively related to those of SPHK1 mRNA in liver cancer tissues. Thus, we conclude that miR-506 depresses the angiogenesis of liver cancer through targeting 3'UTR of SPHK1 mRNA. Our finding provides new insights into the mechanism of tumor angiogenesis.

  8. Methylation status of c-fms oncogene in HCC and its relationship with clinical pathology

    Institute of Scientific and Technical Information of China (English)

    Jun Cui; Dong Hua Yang; Xiang Jun Bi; Zi Rong Fan

    2001-01-01

    @@ INTRODUCTIONThe mechanism that DNA hypomethylation leads toactivation of oncogene and occurrence of malignantneoplasm is being increasingly recognized byresearchers. Normal DNA methylation playsimportant role in stabilizing the phenotype of cell.DNA methylation status reduction and/or patternalteration are related to activation and abnormallyhigh expression of some oncogenes and cellularmalignancy[1-6]. c-fms oncogene encodes for colonystimulating factor 1 receptor (CSF-1R)[7], c-fms/CSF-1R was highly expressed in hepatocellularcarcinoma (HCC) tissue, but the mechanismremained obscure[8,9].

  9. Activating mutation in MET oncogene in familial colorectal cancer

    Directory of Open Access Journals (Sweden)

    Schildkraut Joellen M

    2011-10-01

    Full Text Available Abstract Background In developed countries, the lifetime risk of developing colorectal cancer (CRC is 5%, and it is the second leading cause of death from cancer. The presence of family history is a well established risk factor with 25-35% of CRCs attributable to inherited and/or familial factors. The highly penetrant inherited colon cancer syndromes account for approximately 5%, leaving greater than 20% without clear genetic definition. Familial colorectal cancer has been linked to chromosome 7q31 by multiple affected relative pair studies. The MET proto-oncogene which resides in this chromosomal region is considered a candidate for genetic susceptibility. Methods MET exons were amplified by PCR from germline DNA of 148 affected sibling pairs with colorectal cancer. Amplicons with altered sequence were detected with high-resolution melt-curve analysis using a LightScanner (Idaho Technologies. Samples demonstrating alternative melt curves were sequenced. A TaqMan assay for the specific c.2975C >T change was used to confirm this mutation in a cohort of 299 colorectal cancer cases and to look for allelic amplification in tumors. Results Here we report a germline non-synonymous change in the MET proto-oncogene at amino acid position T992I (also reported as MET p.T1010I in 5.2% of a cohort of sibling pairs affected with CRC. This genetic variant was then confirmed in a second cohort of individuals diagnosed with CRC and having a first degree relative with CRC at prevalence of 4.1%. This mutation has been reported in cancer cells of multiple origins, including 2.5% of colon cancers, and in Conclusions Although the MET p.T992I genetic mutation is commonly found in somatic colorectal cancer tissues, this is the first report also implicating this MET genetic mutation as a germline inherited risk factor for familial colorectal cancer. Future studies on the cancer risks associated with this mutation and the prevalence in different at-risk populations will

  10. Screening for Novel Binding Proteins Interacting with Human Papillomavirus Type 18 E6 Oncogene in the Hela cDNA Library by Yeast Two-Hybrid System

    Institute of Scientific and Technical Information of China (English)

    Shuang LI; Ping LIU; Ling XI; Xuefeng JIANG; Jianfeng ZHOU; Shixuan WANG; Li MENG; Yunping LU; Ding Ma

    2008-01-01

    To screen for novel binding proteins interacting with high-risk HPV 18 E6 oncogene, the strain AH109 was transformed with pGBKT7-HPV18 E6 plasmid, and subsequent transference was utilized to screen for interacting proteins with HPV 18 E6 in human Hela cDNA library. HPVl8 E6 mRNA was expressed in yeast and there was no self-activation and toxicity in AH109. Seven proteins that interacted with HPV18 E6, including transmembrane protein 87B, phosphonoformate im- muno-associated protein 5, vimentin, KM-HN-1 protein, dedicator of cytokinesis 7, vaccinia related kinase 2 and a hypothetical protein, were identified. It was suggested that yeast two-hybrid system is an efficient for screening interacting proteins. The high-risk HPV 18 E6 oncogene may interact with the proteins, which may be associated with signal transduction and transeriptional control, epithelial cell invasion and migration, as well as humoral and cellular immune etc. This investigation provides functional clues for further exploration of potential oncogenesis targets for cancer biotherapy.

  11. miR-19, a component of the oncogenic miR-17∼92 cluster, targets the DNA-end resection factor CtIP

    DEFF Research Database (Denmark)

    Hühn, D; Kousholt, A N; Sørensen, Claus Storgaard

    2014-01-01

    to two highly conserved sequences located in the 3'-untranslated region of CtIP mRNA. We further demonstrate that CtIP expression is repressed by miR-19 during continuous genotoxic stress in a p53-dependent manner. Finally, we report that miR-19 impairs CtIP-mediated DNA-end resection, which results......R-19 still remain largely elusive. CtIP/RBBP8 promotes DNA-end resection, a critical step in the repair of DNA double-strand breaks (DSBs) by homologous recombination (HR), and is considered to function as a tumor suppressor. In this study, we show that miR-19 downregulates CtIP expression by binding...... in reduced HR levels and DNA damage hypersensitivity. By downregulating CtIP, miR-19 overexpression suppresses the faithful repair of DSBs that is crucial for genome maintenance. Our findings thus provide new mechanistic insight into the oncogenic role of the miR-17∼92 cluster.Oncogene advance online...

  12. FOXM1 is an oncogenic mediator in Ewing Sarcoma.

    Directory of Open Access Journals (Sweden)

    Laura Christensen

    Full Text Available Ewing Family Tumors (Ewing Sarcoma and peripheral Primitive Neuroectodermal Tumor are common bone and soft tissue malignancies of childhood, adolescence and young adulthood. Chromosomal translocation in these tumors produces fusion oncogenes of the EWS/ETS class, with EWS/FLI1 being by far the most common. EWS/ETS chimera are the only well established driver mutations in these tumors and they function as aberrant transcription factors. Understanding the downstream genes whose expression is modified has been a central approach to the study of these tumors. FOXM1 is a proliferation associated transcription factor which has increasingly been found to play a role in the pathogenesis of a wide range of human cancers. Here we demonstrate that FOXM1 is expressed in Ewing primary tumors and cell lines. Reduction in FOXM1 expression in Ewing cell lines results in diminished potential for anchorage independent growth. FOXM1 expression is enhanced by EWS/FLI1, though, unlike other tumor systems, it is not driven by expression of the EWS/FLI1 target GLI1. Thiostrepton is a compound known to inhibit FOXM1 by direct binding. We show that Thiostrepton diminishes FOXM1 expression in Ewing cell lines and this reduction reduces cell viability through an apoptotic mechanism. FOXM1 is involved in Ewing tumor pathogenesis and may prove to be a useful therapeutic target in Ewing tumors.

  13. Oncogenic potential diverge among human papillomavirus type 16 natural variants

    Energy Technology Data Exchange (ETDEWEB)

    Sichero, Laura, E-mail: lsichero@gmail.com [Molecular Biology Laboratory, Center of Translational Oncology, Instituto do Cancer do Estado de Sao Paulo-ICESP, Sao Paulo 01246-000 (Brazil); Department of Virology, Ludwig Institute for Cancer Research, Sao Paulo 01323-903 (Brazil); Simao Sobrinho, Joao [Molecular Biology Laboratory, Center of Translational Oncology, Instituto do Cancer do Estado de Sao Paulo-ICESP, Sao Paulo 01246-000 (Brazil); Department of Virology, Ludwig Institute for Cancer Research, Sao Paulo 01323-903 (Brazil); Lina Villa, Luisa [Molecular Biology Laboratory, Center of Translational Oncology, Instituto do Cancer do Estado de Sao Paulo-ICESP, Sao Paulo 01246-000 (Brazil); Department of Virology, Ludwig Institute for Cancer Research, Sao Paulo 01323-903 (Brazil); Department of Radiology, School of Medicine, University of Sao Paulo (Brazil)

    2012-10-10

    We compared E6/E7 protein properties of three different HPV-16 variants: AA, E-P and E-350G. Primary human foreskin keratinocytes (PHFK) were transduced with HPV-16 E6 and E7 and evaluated for proliferation and ability to grow in soft agar. E-P infected keratinocytes presented the lowest efficiency in colony formation. AA and E-350G keratinocytes attained higher capacity for in vitro transformation. We observed similar degradation of TP53 among HPV-16 variants. Furthermore, we accessed the expression profile in early (p5) and late passage (p30) transduced cells of 84 genes commonly involved in carcinogenesis. Most differences could be attributed to HPV-16 E6/E7 expression. In particular, we detected different expression of ITGA2 and CHEK2 in keratinocytes infected with AA and AA/E-350G late passage cells, respectively, and higher expression of MAP2K1 in E-350G transduced keratinocytes. Our results indicate differences among HPV-16 variants that could explain, at least in part, differences in oncogenic potential attributed to these variants.

  14. Control of autophagy by oncogenes and tumor suppressor genes.

    Science.gov (United States)

    Maiuri, M C; Tasdemir, E; Criollo, A; Morselli, E; Vicencio, J M; Carnuccio, R; Kroemer, G

    2009-01-01

    Multiple oncogenes (in particular phosphatidylinositol 3-kinase, PI3K; activated Akt1; antiapoptotic proteins from the Bcl-2 family) inhibit autophagy. Similarly, several tumor suppressor proteins (such as BH3-only proteins; death-associated protein kinase-1, DAPK1; the phosphatase that antagonizes PI3K, PTEN; tuberous sclerosic complex 1 and 2, TSC1 and TSC2; as well as LKB1/STK11) induce autophagy, meaning that their loss reduces autophagy. Beclin-1, which is required for autophagy induction acts as a haploinsufficient tumor suppressor protein, and other essential autophagy mediators (such as Atg4c, UVRAG and Bif-1) are bona fide oncosuppressors. One of the central tumor suppressor proteins, p53 exerts an ambiguous function in the regulation of autophagy. Within the nucleus, p53 can act as an autophagy-inducing transcription factor. Within the cytoplasm, p53 exerts a tonic autophagy-inhibitory function, and its degradation is actually required for the induction of autophagy. The role of autophagy in oncogenesis and anticancer therapy is contradictory. Chronic suppression of autophagy may stimulate oncogenesis. However, once a tumor is formed, autophagy inhibition may be a therapeutic goal for radiosensitization and chemosensitization. Altogether, the current state-of-the art suggests a complex relationship between cancer and deregulated autophagy that must be disentangled by further in-depth investigation.

  15. Human Papillomavirus 16E6 Oncogene Mutation in Cervical Cancer

    Institute of Scientific and Technical Information of China (English)

    Feng Sun; Xiao-qin Ha; Tong-de Lv; Chuan-ping Xing; Bin Liu; Xiao-zhe Cao

    2009-01-01

    Objective: Cervical cancer (CC) is the second most common type of cancer in women worldwide, after breast cancer. High-risk human papillomaviruses (HR-HPVs) are considered to be the major causes of cervical cancer. HPV16 is the most common type of HR-HPVs and HPV16 E6 gene is one of the major oncogenes. Specific mutations are considered as dangerous factors causing CC. This study was designed to find mutations of HPV16 E6 and the relationship between the mutations and the happening of CC.Methods: The tissue DNA was extracted from 15 biopsies of CC. Part of HPV16 E6 gene (nucleotide 201-523) was amplified by polymerase chain reaction (PCR) from the CC tissue DNA. The PCR fragments were sequenced and analyzed.Results: The result of PCR showed that the positive rate of HPV16 E6 was 93.33% (14/15). After sequencing and analyzing, in the 13 out of 14 PCR fragments, 4 maintained prototype (30.77%), 8 had a same 350G mutation (61.54%), and 1 had a 249G mutation (7.69%).Conclusion: This study suggest that there is a high infection rate of HPV in cervical cancer and most of the HPV16 E6 gene has mutations. Those mutations may have an association with the development of cervical cancer.

  16. Re-Configuration of Sphingolipid Metabolism by Oncogenic Transformation

    Directory of Open Access Journals (Sweden)

    Anthony S. Don

    2014-03-01

    Full Text Available The sphingolipids are one of the major lipid families in eukaryotes, incorporating a diverse array of structural variants that exert a powerful influence over cell fate and physiology. Increased expression of sphingosine kinase 1 (SPHK1, which catalyses the synthesis of the pro-survival, pro-angiogenic metabolite sphingosine 1-phosphate (S1P, is well established as a hallmark of multiple cancers. Metabolic alterations that reduce levels of the pro-apoptotic lipid ceramide, particularly its glucosylation by glucosylceramide synthase (GCS, have frequently been associated with cancer drug resistance. However, the simple notion that the balance between ceramide and S1P, often referred to as the sphingolipid rheostat, dictates cell survival contrasts with recent studies showing that highly potent and selective SPHK1 inhibitors do not affect cancer cell proliferation or survival, and studies demonstrating higher ceramide levels in some metastatic cancers. Recent reports have implicated other sphingolipid metabolic enzymes such as acid sphingomyelinase (ASM more strongly in cancer pathogenesis, and highlight lysosomal sphingolipid metabolism as a possible weak point for therapeutic targeting in cancer. This review describes the evidence implicating different sphingolipid metabolic enzymes and their products in cancer pathogenesis, and suggests how newer systems-level approaches may improve our overall understanding of how oncogenic transformation reconfigures sphingolipid metabolism.

  17. The LMO2 oncogene regulates DNA replication in hematopoietic cells.

    Science.gov (United States)

    Sincennes, Marie-Claude; Humbert, Magali; Grondin, Benoît; Lisi, Véronique; Veiga, Diogo F T; Haman, André; Cazaux, Christophe; Mashtalir, Nazar; Affar, El Bachir; Verreault, Alain; Hoang, Trang

    2016-02-02

    Oncogenic transcription factors are commonly activated in acute leukemias and subvert normal gene expression networks to reprogram hematopoietic progenitors into preleukemic stem cells, as exemplified by LIM-only 2 (LMO2) in T-cell acute lymphoblastic leukemia (T-ALL). Whether or not these oncoproteins interfere with other DNA-dependent processes is largely unexplored. Here, we show that LMO2 is recruited to DNA replication origins by interaction with three essential replication enzymes: DNA polymerase delta (POLD1), DNA primase (PRIM1), and minichromosome 6 (MCM6). Furthermore, tethering LMO2 to synthetic DNA sequences is sufficient to transform these sequences into origins of replication. We next addressed the importance of LMO2 in erythroid and thymocyte development, two lineages in which cell cycle and differentiation are tightly coordinated. Lowering LMO2 levels in erythroid progenitors delays G1-S progression and arrests erythropoietin-dependent cell growth while favoring terminal differentiation. Conversely, ectopic expression in thymocytes induces DNA replication and drives these cells into cell cycle, causing differentiation blockade. Our results define a novel role for LMO2 in directly promoting DNA synthesis and G1-S progression.

  18. Proto-oncogene c-erbB2 initiates rat primordial follicle growth via PKC and MAPK pathways

    Science.gov (United States)

    2010-01-01

    Background c-erbB2, a proto-oncogene coding epidermal growth factor receptor-like receptor, also as a chemosensitivity/prognosis marker for gynecologic cancer, may be involved in initiation of growth of rat primordial follicles. The aim of the present study is to investigate the role and signal pathway of c-erbB2 in onset of rat primordial follicle development. Methods The expression of c-erbB2 mRNA and protein in neonatal ovaries cultured 4 and 8 days with/without epidermal growth factor (EGF) were examined by in situ hybridization, RT-PCR and western blot. The function of c-erbB2 in the primordial folliculogenesis was abolished by small interfering RNA transfection. Furthermore, MAPK inhibitor PD98059 and PKC inhibitor calphostin were used to explore the possible signaling pathway of c-erbB2 in primordial folliculogenesis. Results The results showed that c-erbB2 mRNA was expressed in ooplasm and the expression of c-erbB2 decreased after transfection with c-erbB2 siRNA. Treatment with EGF at 50 ng/ml significantly increased c-erbB2 expression and primary and secondary follicle formation in ovaries. However, this augmenting effect was remarkably inhibited by c-erbB2 siRNA transfection. Furthermore, folliculogenesis offset was blocked by calphostin (5 × 10(-4) mmol/L) and PD98059 (5 × 10(-2) mmol/L), but both did not down-regulate c-erbB2 expression. In contrast, the expressions of p-ERK and p-PKC were decreased obviously by c-erbB2 siRNA transfection. Conclusions c-erbB2 initiates rat primordial follicle growth via PKC and MAPK pathways, suggesting an important role of c-erbB2 in rat primordial follicle initiation and development. PMID:20565902

  19. Hydroxytyrosol prevents increase of osteoarthritis markers in human chondrocytes treated with hydrogen peroxide or growth-related oncogene α.

    Directory of Open Access Journals (Sweden)

    Annalisa Facchini

    Full Text Available Hydroxytyrosol (HT, a phenolic compound mainly derived from olives, has been proposed as a nutraceutical useful in prevention or treatment of degenerative diseases. In the present study we have evaluated the ability of HT to counteract the appearance of osteoarthritis (OA features in human chondrocytes. Pre-treatment of monolayer cultures of chondrocytes with HT was effective in preventing accumulation of reactive oxidant species (ROS, DNA damage and cell death induced by H2O2 exposure, as well as the increase in the mRNA level of pro-inflammatory, matrix-degrading and hypertrophy marker genes, such as iNOS, COX-2, MMP-13, RUNX-2 and VEGF. HT alone slightly enhanced ROS production, but did not enhance cell damage and death or the expression of OA-related genes. Moreover HT was tested in an in vitro model of OA, i.e. three-dimensional micromass cultures of chondrocytes stimulated with growth-related oncogene α (GROα, a chemokine involved in OA pathogenesis and known to promote hypertrophy and terminal differentiation of chondrocytes. In micromass constructs, HT pre-treatment inhibited the increases in caspase activity and the level of the messengers for iNOS, COX-2, MMP-13, RUNX-2 and VEGF elicited by GROα. In addition, HT significantly increased the level of SIRT-1 mRNA in the presence of GROα. In conclusion, the present study shows that HT reduces oxidative stress and damage, exerts pro-survival and anti-apoptotic actions and favourably influences the expression of critical OA-related genes in human chondrocytes treated with stressors promoting OA-like features.

  20. Oncogenic and tumor-promoting Spermatophytes and Pteridophytes and their active principles.

    Science.gov (United States)

    Farnsworth, N R; Bingel, A S; Fong, H H; Saleh, A A; Christenson, G M; Saufferer, S M

    1976-08-01

    A survey and discussion are presented of plants classified as Spermatophyta and Pteridophyta, extracts of which have been shown to be oncogenic or tumor-promoting in animals. The active oncogenic and tumor-promoting principles, where known, have been identified. They represent tannins; pyrrolizidine, indole, tropolone, quinoline, purine, and benzophenanthridine alkaloids; nitroso compounds; triterpene glycosides; lignans; isoflavans; allyl benzenoids; simple (nu-pyrenes; and carbocyclic hydroxy acids. A total of 28 compounds of known structure have been identified as oncogens and several phorbol esters as tumor-promoters. Plants known to contain any of the 28 oncogens (excluding shikimic acid and caffeine) have been tabulated; they represent at least 454 species, 110 genera, and 34 families of Spermatophyta and Pteridophyta.

  1. Alterations in metastatic properties of hepatocellular carcinoma cell following H-ras oncogene transfection

    Institute of Scientific and Technical Information of China (English)

    Qing Wang; Zhi Ying Lin; Xiao Li Feng

    2001-01-01

    AIM To demonstrate the relationship betweenH-ras oncogene and hepatocellular carcinoma(HCC) metastasis.METHODS Activated H-ras oncogene wastransfected into SMMC 7721, a cell line derivedfrom human HCC, by calcium phosphatetransfection method. Some metastasis-relatedparameters were detected in vitro, includingadhesion assay, migration assay, expression ofcollagenase ⅣV (c ⅣV ase) and epidermal growthfactor receptor (EGFR).RESULTS The abilities of H-ras-transfected cellclones in adhesion to laminin (LN) or fibronectin(FN), migration, c Ⅳ ase secretion increasedmarkedly, and the expression of EGFR elevatedmoderately. More importantly, these alterationswere consistent positively with the expressionof p21, the protein product of H-ras oncogene.CONCLUSION H-ras oncogene could inducethe metastatic phenotype of HCC cell in vitro toraise its metastatic potential.

  2. Analysis of acquired resistance to cis-diamminedichloroplatinum(II) in oncogene transfected SHOK cells

    Energy Technology Data Exchange (ETDEWEB)

    Kinashi, Yuko; Masunaga, Shinichiro; Suzuki, Minoru; Ono, Koji; Akaboshi, Mitsuhiko [Kyoto Univ., Kumatori, Osaka (Japan). Research Reactor Inst.; Watanabe, Masami

    1998-02-01

    SHOK (Syrian hamster Osaka-Kanazawa) cells were transfected with activated oncogenes (v-mos, c-myc, N-ras, H-ras, K-ras). These oncogene transfected cells were treated with {sup 195m}Pt-cis-diamminedichloroplatinum(II) (CDDP). Clonogenic cell survival assay showed that oncogene-transfected cells exhibited a 1.3-4.8 fold increases resistance to cisplatin compared to the parental SHOK cells. The CDDP concentration binding to DNA, RNA and protein were measured by counting the {sup 195m}Pt-radioactivity. The CDDP uptake was decreased in these oncogene transfected cells. The CDDP uptake in DNA of H-ras transfected cells decreased faster than control SHOK cells. (author)

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

    African Journals Online (AJOL)

    Makia Marafie

    2016-09-17

    Sep 17, 2016 ... multiple members of an Arab family with variable onset of MEN type ... fashion and caused by germline mutation in RET proto- oncogene. The main .... ing sudden severe high blood pressure crises that required immediate ...

  4. Characterizing exogenous mRNA delivery, trafficking, cytoplasmic release and RNA-protein correlations at the level of single cells.

    Science.gov (United States)

    Kirschman, Jonathan L; Bhosle, Sushma; Vanover, Daryll; Blanchard, Emmeline L; Loomis, Kristin H; Zurla, Chiara; Murray, Kathryn; Lam, Blaine C; Santangelo, Philip J

    2017-07-07

    The use of synthetic messenger ribonucleic acid (mRNA) to express specific proteins is a highly promising therapeutic and vaccine approach that avoids many safety issues associated with viral or DNA-based systems. However, in order to optimize mRNA designs and delivery, technology advancements are required to study fundamental mechanisms of mRNA uptake and localization at the single-cell and tissue level. Here, we present a single RNA sensitive fluorescent labeling method which allows us to label and visualize synthetic mRNA without significantly affecting function. This approach enabled single cell characterization of mRNA uptake and release kinetics from endocytic compartments, the measurement of mRNA/protein correlations, and motivated the investigation of mRNA induced cellular stress, all important mechanisms influencing protein production. In addition, we demonstrated this approach can facilitate near-infrared imaging of mRNA localization in vivo and in ex-vivo tissue sections, which will facilitate mRNA trafficking studies in pre-clinical models. Overall, we demonstrate the ability to study fundamental mechanisms necessary to optimize delivery and therapeutic strategies, in order to design the next generation of novel mRNA therapeutics and vaccines. © The Author(s) 2017. Published by Oxford University Press on behalf of Nucleic Acids Research.

  5. Dana-Farber Cancer Institute: Discovery of Novel Oncogenes | Office of Cancer Genomics

    Science.gov (United States)

    Widespread recurrent copy number alterations are observed across the majority of human cancers, yet the specific targets of such amplified or deleted regions remain undefined. Here, the CTD2 Center at the Dana Farber Cancer Institute took a systematic approach using cDNA overexpression screening to identify and validate oncogenes residing in such amplified regions. In representative examples, these experiments have identified the adaptor proteins CRKL, GAB2, FRS2 and the TLOC and SKIL proteins as novel amplified oncogenes.

  6. Duplication of the MYB oncogene in T cell acute lymphoblastic leukemia.

    Science.gov (United States)

    Lahortiga, Idoya; De Keersmaecker, Kim; Van Vlierberghe, Pieter; Graux, Carlos; Cauwelier, Barbara; Lambert, Frederic; Mentens, Nicole; Beverloo, H Berna; Pieters, Rob; Speleman, Frank; Odero, Maria D; Bauters, Marijke; Froyen, Guy; Marynen, Peter; Vandenberghe, Peter; Wlodarska, Iwona; Meijerink, Jules P P; Cools, Jan

    2007-05-01

    We identified a duplication of the MYB oncogene in 8.4% of individuals with T cell acute lymphoblastic leukemia (T-ALL) and in five T-ALL cell lines. The duplication is associated with a threefold increase in MYB expression, and knockdown of MYB expression initiates T cell differentiation. Our results identify duplication of MYB as an oncogenic event and suggest that MYB could be a therapeutic target in human T-ALL.

  7. Presence of high risk HPV DNA but indolent transcription of E6/E7 oncogenes in invasive ductal carcinoma of breast.

    Science.gov (United States)

    Wang, Depu; Fu, Ling; Shah, Walayat; Zhang, Jingwen; Yan, Yan; Ge, Xinhong; He, Jianjun; Wang, Yili; Li, Xu

    2016-12-01

    The causative role of high risk human papillomavirus (HR-HPV) in breast cancer development is controversial, though a number of reports have identified HR-HPV DNA in breast cancer specimens. Nevertheless, most studies to date have focused primarily on viral DNA rather than the viral transcription. The aim of this study was to investigate the presence of HR-HPV in breast cancer tissues at HPV DNA level and HPV oncogenes mRNA level by in situ hybridization (ISH). One hundred and forty six (146) cases of breast invasive ductal carcinoma(IDC) and 83 cases of benign breast lesions were included in the study. Type specific oligonucleotide probes were used for the DNA detection of HPV 16,18 and 58 by ISH. HR-HPV oncogenes mRNA was assayed by novel RNAscope HR-HPV HR7 assay ISH. p16 protein expression was evaluated by immunohistochemistry (IHC). HR-HPV 16,18 and 58 DNA were detected in 52 out of 146 (35.6%) IDC and in 3 out of 83 (3.6%) benign breast lesions by ISH. The HR-HPV mRNAs was detected only in a few specimens with strong HPV DNA positivity(4/25) in a few scattered cancer cells with very weak punctate nuclear and/or cytoplasmic staining. p16 over-expression did not correlate with the HPV DNA positive breast cancer samples(17/52 HPVDNA+ vs 28/94 HPV DNA-, p=0.731). HR-HPVs certainly exist in breast cancer tissue with less active transcription, which implies that the causal role of HPV in breast cancer development need further study. Copyright © 2016 Elsevier GmbH. All rights reserved.

  8. Molecular genetic characterization of p53 mutated oropharyngeal squamous cell carcinoma cells transformed with human papillomavirus E6 and E7 oncogenes.

    Science.gov (United States)

    Oh, Ji-Eun; Kim, Jeong-Oh; Shin, Jung-Young; Zhang, Xiang-Hua; Won, Hye-Sung; Chun, Sang-Hoon; Jung, Chan-Kwon; Park, Won-Sang; Nam, Suk-Woo; Eun, Jung-Woo; Kang, Jin-Hyoung

    2013-08-01

    Patients with HPV-positive oropharyngeal cancer show better tumor response to radiation or chemotherapy than patients with HPV-negative cancer. HPV oncoprotein E6 binds and degrades a typically wild-type p53 protein product. However, HPV16 infection and p53 mutation infrequently coexist in a subset of HNSCCs. The purpose of this study was to investigate the mechanisms through which tumor biology and molecular genetic mechanisms change when two HPV-negative, p53-mutated oropharyngeal cell lines (YD8, non-disruptive p53 mutation; YD10B, disruptive p53 mutation) derived from patients with a history of heavy smoking are transfected with HPV E6 and E7 oncogenes in vitro. Transfection with HPV E6 and E7 oncogenes in YD8, reduced the abundance of proteins encoded by tumor suppressor genes, such as p-p53 and p-Rb. Cell proliferative activity was increased in the cells transfected with E6E7 compared to cells transfected with vector alone (P=0.09), whereas the invasiveness of E6E7-transfected cells was significantly reduced (P=0.02). cDNA microarray of the transfected cells with E6E7 showed significant changes in mRNA expression in several signaling pathways, including focal adhesion, JAK-STAT signaling pathway, cell cycle and p53 signaling pathway. Regarding the qPCR array for the p53 signaling pathway, the mRNA expression of STAT1 was remarkably upregulated by 6.47-fold (Pcell carcinoma cases with non-disruptive p53 mutations.

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2016-09-15

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

  10. Hyaluronan synthase 3 mediated oncogenic action through forming inter-regulation loop with tumor necrosis factor alpha in oral cancer

    Science.gov (United States)

    Kuo, Yi-Zih; Fang, Wei-Yu; Huang, Cheng-Chih; Tsai, Sen-Tien; Wang, Yi-Ching; Yang, Chih-Li; Wu, Li-Wha

    2017-01-01

    Hyaluronan (HA) is a major extracellular matrix component. However, its role and mediation in oral cancer remains elusive. Hyaluronan synthase 3 (HAS3), involved in pro-inflammatory short chain HA synthesis, was the predominant synthase in oral cancer cells and tissues. HAS3 overexpression significantly increased oral cancer cell migration, invasion and xenograft tumorigenesis accompanied with the increased expression of tumor necrosis factor alpha (TNF-α) and monocyte chemoattractant protein 1 (MCP-1). Conversely, HAS3 depletion abrogated HAS3-mediated stimulation. HAS3 induced oncogenic actions partly through activating EGFR-SRC signaling. HAS3-derived HA release into extracellular milieu enhanced transendothelial monocyte migration and MCP-1 expression, which was attenuated by anti-HAS3 antibodies or a HAS inhibitor, 4-Methylumbelliferone (4-MU). The NF-κB-binding site III at -1692 to -1682 bp upstream from the transcript 1 start site in HAS3 proximal promoter was the most responsive to TNF-α-stimulated transcription. ChIP-qPCR analysis confirmed the highest NF-κB-p65 enrichment on site III. Increased HAS3 mRNA expression was negatively correlated with the overall survival of oral cancer patients. A concomitant increase of TNF-α, a stimulus for HAS3 expression, with HAS3 expression was not only associated with lymph node metastasis but also negated clinical outcome. Together, HAS3 and TNF-α formed an inter-regulation loop to enhance tumorigenesis in oral cancer. PMID:28107185

  11. Negative Selection and Chromosome Instability Induced by Mad2 Overexpression Delay Breast Cancer but Facilitate Oncogene-Independent Outgrowth

    Directory of Open Access Journals (Sweden)

    Konstantina Rowald

    2016-06-01

    Full Text Available Chromosome instability (CIN is associated with poor survival and therapeutic outcome in a number of malignancies. Despite this correlation, CIN can also lead to growth disadvantages. Here, we show that simultaneous overexpression of the mitotic checkpoint protein Mad2 with KrasG12D or Her2 in mammary glands of adult mice results in mitotic checkpoint overactivation and a delay in tumor onset. Time-lapse imaging of organotypic cultures and pathologic analysis prior to tumor establishment reveals error-prone mitosis, mitotic arrest, and cell death. Nonetheless, Mad2 expression persists and increases karyotype complexity in Kras tumors. Faced with the selective pressure of oncogene withdrawal, Mad2-positive tumors have a higher frequency of developing persistent subclones that avoid remission and continue to grow.

  12. Negative Selection and Chromosome Instability Induced by Mad2 Overexpression Delay Breast Cancer but Facilitate Oncogene-Independent Outgrowth.

    Science.gov (United States)

    Rowald, Konstantina; Mantovan, Martina; Passos, Joana; Buccitelli, Christopher; Mardin, Balca R; Korbel, Jan O; Jechlinger, Martin; Sotillo, Rocio

    2016-06-21

    Chromosome instability (CIN) is associated with poor survival and therapeutic outcome in a number of malignancies. Despite this correlation, CIN can also lead to growth disadvantages. Here, we show that simultaneous overexpression of the mitotic checkpoint protein Mad2 with Kras(G12D) or Her2 in mammary glands of adult mice results in mitotic checkpoint overactivation and a delay in tumor onset. Time-lapse imaging of organotypic cultures and pathologic analysis prior to tumor establishment reveals error-prone mitosis, mitotic arrest, and cell death. Nonetheless, Mad2 expression persists and increases karyotype complexity in Kras tumors. Faced with the selective pressure of oncogene withdrawal, Mad2-positive tumors have a higher frequency of developing persistent subclones that avoid remission and continue to grow.

  13. Oncogenic ETS proteins mimic activated RAS/MAPK signaling in prostate cells

    Science.gov (United States)

    Hollenhorst, Peter C.; Ferris, Mary W.; Hull, Megan A.; Chae, Heejoon; Kim, Sun; Graves, Barbara J.

    2011-01-01

    The aberrant expression of an oncogenic ETS transcription factor is implicated in the progression of the majority of prostate cancers, 40% of melanomas, and most cases of gastrointestinal stromal tumor and Ewing's sarcoma. Chromosomal rearrangements in prostate cancer result in overexpression of any one of four ETS transcription factors. How these four oncogenic ETS genes differ from the numerous other ETS genes expressed in normal prostate and contribute to tumor progression is not understood. We report that these oncogenic ETS proteins, but not other ETS factors, enhance prostate cell migration. Genome-wide binding analysis matched this specific biological function to occupancy of a unique set of genomic sites highlighted by the presence of ETS- and AP-1-binding sequences. ETS/AP-1-binding sequences are prototypical RAS-responsive elements, but oncogenic ETS proteins activated a RAS/MAPK transcriptional program in the absence of MAPK activation. Thus, overexpression of oncogenic ETS proteins can replace RAS/MAPK pathway activation in prostate cells. The genomic description of this ETS/AP-1-regulated, RAS-responsive, gene expression program provides a resource for understanding the role of these ETS factors in both an oncogenic setting and the developmental processes where these genes normally function. PMID:22012618

  14. Genetic disruption of oncogenic Kras sensitizes lung cancer cells to Fas receptor-mediated apoptosis.

    Science.gov (United States)

    Mou, Haiwei; Moore, Jill; Malonia, Sunil K; Li, Yingxiang; Ozata, Deniz M; Hough, Soren; Song, Chun-Qing; Smith, Jordan L; Fischer, Andrew; Weng, Zhiping; Green, Michael R; Xue, Wen

    2017-04-04

    Genetic lesions that activate KRAS account for ∼30% of the 1.6 million annual cases of lung cancer. Despite clinical need, KRAS is still undruggable using traditional small-molecule drugs/inhibitors. When oncogenic Kras is suppressed by RNA interference, tumors initially regress but eventually recur and proliferate despite suppression of Kras Here, we show that tumor cells can survive knockout of oncogenic Kras, indicating the existence of Kras-independent survival pathways. Thus, even if clinical KRAS inhibitors were available, resistance would remain an obstacle to treatment. Kras-independent cancer cells exhibit decreased colony formation in vitro but retain the ability to form tumors in mice. Comparing the transcriptomes of oncogenic Kras cells and Kras knockout cells, we identified 603 genes that were specifically up-regulated in Kras knockout cells, including the Fas gene, which encodes a cell surface death receptor involved in physiological regulation of apoptosis. Antibodies recognizing Fas receptor efficiently induced apoptosis of Kras knockout cells but not oncogenic Kras-expressing cells. Increased Fas expression in Kras knockout cells was attributed to decreased association of repressive epigenetic marks at the Fas promoter. Concordant with this observation, treating oncogenic Kras cells with histone deacetylase inhibitor and Fas-activating antibody efficiently induced apoptosis, thus bypassing the need to inhibit Kras. Our results suggest that activation of Fas could be exploited as an Achilles' heel in tumors initiated by oncogenic Kras.

  15. [Oncogenes RET/PTC and mechanisms of their involvement in thyroid cancerogenesis].

    Science.gov (United States)

    Voskoboĭnyk, L H

    2009-01-01

    Papillary thyroid carcinomas are the most common type of thyroid oncopathology, and are rather often associated with the expression of RET/PTC oncogens. The first oncogen RET/PTC1 was isolated more than 20 years ago. Now 13 different forms of RET/PTC are known, and 12 different partner-genes are described, that could be involved in formation of RET/PTC oncogenes. The most common of them are RET/PTC1 and RET/PTC3 forms. The great majority of oncogens RET/PTC, except for two--ELKS-RET and HOOK3-RET, have been founded in radioaction-induced thyroid tumors. There is an opinion that the key role in development of papillary thyroid carcinomas belongs to RET/PTC oncogens. The data about different types of RET/PTC oncogens, factors, that lead to their formation have been described in the present review. Also different mechanisms of activation of transduction pathways and gene's expression in thyroid cells after RET/PTC induction have been presented.

  16. Single-cell detection of mRNA expression using nanofountain-probe electroporated molecular beacons.

    Science.gov (United States)

    Giraldo-Vela, Juan P; Kang, Wonmo; McNaughton, Rebecca L; Zhang, Xuemei; Wile, Brian M; Tsourkas, Andrew; Bao, Gang; Espinosa, Horacio D

    2015-05-01

    New techniques for single-cell analysis enable new discoveries in gene expression and systems biology. Time-dependent measurements on individual cells are necessary, yet the common single-cell analysis techniques used today require lysing the cell, suspending the cell, or long incubation times for transfection, thereby interfering with the ability to track an individual cell over time. Here a method for detecting mRNA expression in live single cells using molecular beacons that are transfected into single cells by means of nanofountain probe electroporation (NFP-E) is presented. Molecular beacons are oligonucleotides that emit fluorescence upon binding to an mRNA target, rendering them useful for spatial and temporal studies of live cells. The NFP-E is used to transfect a DNA-based beacon that detects glyceraldehyde 3-phosphate dehydrogenase and an RNA-based beacon that detects a sequence cloned in the green fluorescence protein mRNA. It is shown that imaging analysis of transfection and mRNA detection can be performed within seconds after electroporation and without disturbing adhered cells. In addition, it is shown that time-dependent detection of mRNA expression is feasible by transfecting the same single cell at different time points. This technique will be particularly useful for studies of cell differentiation, where several measurements of mRNA expression are required over time.

  17. Spliceosome mutations exhibit specific associations with epigenetic modifiers and proto-oncogenes mutated in myelodysplastic syndrome.

    Science.gov (United States)

    Mian, Syed A; Smith, Alexander E; Kulasekararaj, Austin G; Kizilors, Aytug; Mohamedali, Azim M; Lea, Nicholas C; Mitsopoulos, Konstantinos; Ford, Kevin; Nasser, Erick; Seidl, Thomas; Mufti, Ghulam J

    2013-07-01

    The recent identification of acquired mutations in key components of the spliceosome machinery strongly implicates abnormalities of mRNA splicing in the pathogenesis of myelodysplastic syndromes. However, questions remain as to how these aberrations functionally combine with the growing list of mutations in genes involved in epigenetic modification and cell signaling/transcription regulation identified in these diseases. In this study, amplicon sequencing was used to perform a mutation screen in 154 myelodysplastic syndrome patients using a 22-gene panel, including commonly mutated spliceosome components (SF3B1, SRSF2, U2AF1, ZRSR2), and a further 18 genes known to be mutated in myeloid cancers. Sequencing of the 22-gene panel revealed that 76% (n=117) of the patients had mutations in at least one of the genes, with 38% (n=59) having splicing gene mutations and 49% (n=75) patients harboring more than one gene mutation. Interestingly, single and specific epigenetic modifier mutations tended to coexist with SF3B1 and SRSF2 mutations (P<0.03). Furthermore, mutations in SF3B1 and SRSF2 were mutually exclusive to TP53 mutations both at diagnosis and at the time of disease transformation. Moreover, mutations in FLT3, NRAS, RUNX1, CCBL and C-KIT were more likely to co-occur with splicing factor mutations generally (P<0.02), and SRSF2 mutants in particular (P<0.003) and were significantly associated with disease transformation (P<0.02). SF3B1 and TP53 mutations had varying impacts on overall survival with hazard ratios of 0.2 (P<0.03, 95% CI, 0.1-0.8) and 2.1 (P<0.04, 95% CI, 1.1-4.4), respectively. Moreover, patients with splicing factor mutations alone had a better overall survival than those with epigenetic modifier mutations, or cell signaling/transcription regulator mutations with and without coexisting mutations of splicing factor genes, with worsening prognosis (P<0.001). These findings suggest that splicing factor mutations are maintained throughout disease

  18. Increased IL-10 mRNA and IL-23 mRNA expression in multiple sclerosis

    DEFF Research Database (Denmark)

    Krakauer, Martin; Sorensen, P; Khademi, M

    2008-01-01

    of the regulatory cytokine IL-10. The elevated IL-23 mRNA levels in MS patients are noteworthy in view of the newly discovered IL-23-driven Th17 T-cell subset, which is crucial in animal models of MS. Since IFN-beta therapy resulted in decreased IL-23 mRNA levels, the Th17 axis could be another target of IFN...

  19. SUMOylation Confers Posttranslational Stability on NPM-ALK Oncogenic Protein

    Directory of Open Access Journals (Sweden)

    Deeksha Vishwamitra

    2015-09-01

    Full Text Available Nucleophosmin-anaplastic lymphoma kinase–expressing (NPM-ALK+ T-cell lymphoma is an aggressive form of cancer that commonly affects children and adolescents. The expression of NPM-ALK chimeric oncogene results from the chromosomal translocation t(2;5(p23;q35 that causes the fusion of the ALK and NPM genes. This translocation generates the NPM-ALK protein tyrosine kinase that forms the constitutively activated NPM-ALK/NPM-ALK homodimers. In addition, NPM-ALK is structurally associated with wild-type NPM to form NPM/NPM-ALK heterodimers, which can translocate to the nucleus. The mechanisms that sustain the stability of NPM-ALK are not fully understood. SUMOylation is a posttranslational modification that is characterized by the reversible conjugation of small ubiquitin-like modifiers (SUMOs with target proteins. SUMO competes with ubiquitin for substrate binding and therefore, SUMOylation is believed to protect target proteins from proteasomal degradation. Moreover, SUMOylation contributes to the subcellular distribution of target proteins. Herein, we found that the SUMOylation pathway is deregulated in NPM-ALK+ T-cell lymphoma cell lines and primary lymphoma tumors from patients. We also identified Lys24 and Lys32 within the NPM domain as the sites where NPM-ALK conjugates with SUMO-1 and SUMO-3. Importantly, antagonizing SUMOylation by the SENP1 protease decreased the accumulation of NPM-ALK and suppressed lymphoma cell viability, proliferation, and anchorage-independent colony formation. One possible mechanism for the SENP1-mediated decrease in NPM-ALK levels was the increase in NPM-ALK association with ubiquitin, which facilitates its degradation. Our findings propose a model in which aberrancies in SUMOylation contribute to the pathogenesis of NPM-ALK+ T-cell lymphoma. Unraveling such pathogenic mechanisms may lead to devising novel strategies to eliminate this aggressive neoplasm.

  20. SUMOylation Confers Posttranslational Stability on NPM-ALK Oncogenic Protein.

    Science.gov (United States)

    Vishwamitra, Deeksha; Curry, Choladda V; Shi, Ping; Alkan, Serhan; Amin, Hesham M

    2015-09-01

    Nucleophosmin-anaplastic lymphoma kinase-expressing (NPM-ALK+) T-cell lymphoma is an aggressive form of cancer that commonly affects children and adolescents. The expression of NPM-ALK chimeric oncogene results from the chromosomal translocation t(2;5)(p23;q35) that causes the fusion of the ALK and NPM genes. This translocation generates the NPM-ALK protein tyrosine kinase that forms the constitutively activated NPM-ALK/NPM-ALK homodimers. In addition, NPM-ALK is structurally associated with wild-type NPM to form NPM/NPM-ALK heterodimers, which can translocate to the nucleus. The mechanisms that sustain the stability of NPM-ALK are not fully understood. SUMOylation is a posttranslational modification that is characterized by the reversible conjugation of small ubiquitin-like modifiers (SUMOs) with target proteins. SUMO competes with ubiquitin for substrate binding and therefore, SUMOylation is believed to protect target proteins from proteasomal degradation. Moreover, SUMOylation contributes to the subcellular distribution of target proteins. Herein, we found that the SUMOylation pathway is deregulated in NPM-ALK+ T-cell lymphoma cell lines and primary lymphoma tumors from patients. We also identified Lys24 and Lys32 within the NPM domain as the sites where NPM-ALK conjugates with SUMO-1 and SUMO-3. Importantly, antagonizing SUMOylation by the SENP1 protease decreased the accumulation of NPM-ALK and suppressed lymphoma cell viability, proliferation, and anchorage-independent colony formation. One possible mechanism for the SENP1-mediated decrease in NPM-ALK levels was the increase in NPM-ALK association with ubiquitin, which facilitates its degradation. Our findings propose a model in which aberrancies in SUMOylation contribute to the pathogenesis of NPM-ALK+ T-cell lymphoma. Unraveling such pathogenic mechanisms may lead to devising novel strategies to eliminate this aggressive neoplasm.

  1. CXCR4 in breast cancer: oncogenic role and therapeutic targeting

    Directory of Open Access Journals (Sweden)

    Xu C

    2015-08-01

    Full Text Available Chao Xu,1,* Hong Zhao,1,* Haitao Chen,1 Qinghua Yao2,3 1First Clinical College of Zhejiang Chinese Medical University, 2Department of Integrated Traditional Chinese and Western Medicine, Zhejiang Cancer Hospital, 3Key Laboratory of Integrated Traditional Chinese and Western Medicine, Zhejiang Cancer Hospital, Hangzhou, People’s Republic of China *These authors contributed equally to this work Abstract: Chemokines are 8–12 kDa peptides that function as chemoattractant cytokines and are involved in cell activation, differentiation, and trafficking. Chemokines bind to specific G-protein-coupled seven-span transmembrane receptors. Chemokines play a fundamental role in the regulation of a variety of cellular, physiological, and developmental processes. Their aberrant expression can lead to a variety of human diseases including cancer. C-X-C chemokine receptor type 4 (CXCR4, also known as fusin or CD184, is an alpha-chemokine receptor specific for stromal-derived-factor-1 (SDF-1 also called CXCL12. CXCR4 belongs to the superfamily of the seven transmembrane domain heterotrimeric G protein-coupled receptors and is functionally expressed on the cell surface of various types of cancer cells. CXCR4 also plays a role in the cell proliferation and migration of these cells. Recently, CXCR4 has been reported to play an important role in cell survival, proliferation, migration, as well as metastasis of several cancers including breast cancer. This review is mainly focused on the current knowledge of the oncogenic role and potential drugs that target CXCR4 in breast cancer. Additionally, CXCR4 proangiogenic molecular mechanisms will be reviewed. Strict biunivocal binding affinity and activation of CXCR4/CXCL12 complex make CXCR4 a unique molecular target for prevention and treatment of breast cancer. Keywords: breast cancer, CXCR4, drug target, chemokine, angiogenesis

  2. A transcriptome map of cellular transformation by the fos oncogene

    Directory of Open Access Journals (Sweden)

    Ruan Hong

    2005-05-01

    Full Text Available Abstract Background The c-fos gene was originally identified as the cellular homolog of the oncogene v-fos carried by the Finkel-Biskis-Jenkins and Finkel-Biskis-Reilly murine osteogenic sarcoma retroviruses. Sustained expression of fos is sufficient to induce cellular transformation in vitro and tumorigenesis in vivo. Fos functions as a component of the AP-1 transcription factor complex to regulate gene transcription and several differentially expressed genes have been identified in cells transformed by fos. We have extended these studies by constructing a cellular system for conditional transformation by v-fos. Using Affymetrix-based DNA microarray technology, we analyzed transcriptional changes over the course of transformation and reversion in an inducible v-fos system. Results Microarray analyses of temporal gene expression during the process of v-fos mediated cellular transformation and morphological reversion revealed a remarkably dynamic transcriptome. Of the more than 8000 genes analyzed in this study, 3766 genes were categorized into 18 gene-expression patterns by using self-organizing map analysis. By combining the analysis of gene expression profiles in stably transformed cells with the analysis of sequential expression patterns during conditional transformation, we identified a relatively small cohort of genes implicated in v-fos mediated cellular transformation. Conclusion This approach defines a general conditional cell transformation system that can be used to study the endogenous transcription regulatory mechanisms involved in transformation and tumorigenesis. In addition, this study is the first reported analysis of dynamic changes in gene expression throughout experimentally controlled morphological transformation mediated by v-fos.

  3. Gene regulation by mRNA editing

    Energy Technology Data Exchange (ETDEWEB)

    Ashkenas, J. [Univ. of Washington, Seattle, WA (United States)

    1997-02-01

    The commonly cited figure of 10{sup 5} genes in the human genome represents a tremendous underestimate of our capacity to generate distinct gene products with unique functions. Our cells possess an impressive collection of tools for altering the products of a single gene to create a variety of proteins. The different gene products may have related but distinct functions, allowing cells of different types or at different developmental stages to fine-tune their patterns of gene expression. These tools may act in the cytoplasm, as when proteins undergo post-translational modifications, or in the nucleus, in the processing of pre-mRNA. Two forms of intranuclear fine-tuning are well established and widely studied: alternative splicing of pre-mRNAs and alternative polyadenylation site selection. In recent years it has become clear that cells possess yet another tool to create RNA sequence diversity, mRNA editing. The term {open_quotes}editing{close_quotes} is applied to posttranscriptional modifications of a purine or pyrimidine, which alter an mRNA sequence as it is read, for example, by ribosomes. Covalent changes to the structure of nucleotide bases are well known to occur on tRNA and rRNA molecules, but such changes in mRNA sequence are novel in that they have the capacity to change specific protein sequences. 43 refs., 1 fig.

  4. A screen identifies the oncogenic micro-RNA miR-378a-5p as a negative regulator of oncogene-induced senescence.

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    Susanne Marije Kooistra

    Full Text Available Oncogene-induced senescence (OIS can occur in response to hyperactive oncogenic signals and is believed to be a fail-safe mechanism protecting against tumorigenesis. To identify new factors involved in OIS, we performed a screen for microRNAs that can overcome or inhibit OIS in human diploid fibroblasts. This screen led to the identification of miR-378a-5p and in addition several other miRNAs that have previously been shown to play a role in senescence. We show that ectopic expression of miR-378a-5p reduces the expression of several senescence markers, including p16(INK4A and senescence-associated β-galactosidase. Moreover, cells with ectopic expression of miR-378a-5p retain proliferative capacity even in the presence of an activated Braf oncogene. Finally, we identified several miR-378a-5p targets in diploid fibroblasts that might explain the mechanism by which the microRNA can delay OIS. We speculate that miR-378a-5p might positively influence tumor formation by delaying OIS, which is consistent with a known pro-oncogenic function of this microRNA.

  5. Spi-1, Fli-1 and Fli-3 (miR-17-92 oncogenes contribute to a single oncogenic network controlling cell proliferation in friend erythroleukemia.

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    Samer Kayali

    Full Text Available Clonal erythroleukemia developing in susceptible mice infected by Friend virus complex are associated with highly recurrent proviral insertions at one of three loci called Spi-1, Fli-1 or Fli-3, leading to deregulated expression of oncogenic Spi-1 or Fli-1 transcription factors or miR-17-92 miRNA cluster, respectively. Deregulated expression of each of these three oncogenes has been independently shown to contribute to cell proliferation of erythroleukemic clones. Previous studies showed a close relationship between Spi-1 and Fli-1, which belong to the same ETS family, Spi-1 activating fli-1 gene, and both Spi-1 and Fli-1 activating multiple common target genes involved in ribosome biogenesis. In this study, we demonstrated that Spi-1 and Fli-1 are also involved in direct miR-17-92 transcriptional activation through their binding to a conserved ETS binding site in its promoter. Moreover, we demonstrated that physiological re-expression of exogenous miR-17 and miR-20a are able to partially rescue the proliferation loss induced by Fli-1 knock-down and identified HBP1 as a target of these miRNA in erythroleukemic cells. These results establish that three of the most recurrently activated oncogenes in Friend erythroleukemia are actually involved in a same oncogenic network controlling cell proliferation. The putative contribution of a similar ETS-miR-17-92 network module in other normal or pathological proliferative contexts is discussed.

  6. Spi-1, Fli-1 and Fli-3 (miR-17-92) oncogenes contribute to a single oncogenic network controlling cell proliferation in friend erythroleukemia.

    Science.gov (United States)

    Kayali, Samer; Giraud, Guillaume; Morlé, François; Guyot, Boris

    2012-01-01

    Clonal erythroleukemia developing in susceptible mice infected by Friend virus complex are associated with highly recurrent proviral insertions at one of three loci called Spi-1, Fli-1 or Fli-3, leading to deregulated expression of oncogenic Spi-1 or Fli-1 transcription factors or miR-17-92 miRNA cluster, respectively. Deregulated expression of each of these three oncogenes has been independently shown to contribute to cell proliferation of erythroleukemic clones. Previous studies showed a close relationship between Spi-1 and Fli-1, which belong to the same ETS family, Spi-1 activating fli-1 gene, and both Spi-1 and Fli-1 activating multiple common target genes involved in ribosome biogenesis. In this study, we demonstrated that Spi-1 and Fli-1 are also involved in direct miR-17-92 transcriptional activation through their binding to a conserved ETS binding site in its promoter. Moreover, we demonstrated that physiological re-expression of exogenous miR-17 and miR-20a are able to partially rescue the proliferation loss induced by Fli-1 knock-down and identified HBP1 as a target of these miRNA in erythroleukemic cells. These results establish that three of the most recurrently activated oncogenes in Friend erythroleukemia are actually involved in a same oncogenic network controlling cell proliferation. The putative contribution of a similar ETS-miR-17-92 network module in other normal or pathological proliferative contexts is discussed.

  7. Increased mRNA Levels of TCF7L2 and MYC of the Wnt Pathway in Tg-ArcSwe Mice and Alzheimer's Disease Brain

    Directory of Open Access Journals (Sweden)

    Elin S. Blom

    2011-01-01

    Full Text Available Several components in the Wnt pathway, including β-catenin and glycogen synthase kinase 3 beta, have been implied in AD pathogenesis. Here, mRNA brain levels from five-month-old tg-ArcSwe and nontransgenic mice were compared using Affymetrix microarray analysis. With surprisingly small overall changes, Wnt signaling was the most affected pathway with altered expression of nine genes in tg-ArcSwe mice. When analyzing mRNA levels of these genes in human brain, transcription factor 7-like 2 (TCF7L2 and v-myc myelocytomatosis viral oncogene homolog (MYC, were increased in Alzheimer's disease (AD (P<.05. Furthermore, no clear differences in TCF7L2 and MYC mRNA were found in brains with frontotemporal lobar degeneration, suggesting that altered regulation of these Wnt-related genes could be specific to AD. Finally, mRNA levels of three neurogenesis markers were analyzed. Increased mRNA levels of dihydropyrimidinase-like 3 were observed in AD brain, suggesting that altered Wnt pathway regulation may signify synaptic rearrangement or neurogenesis.

  8. CCL5 promotes proliferation of MCF-7 cells through mTOR-dependent mRNA translation

    Energy Technology Data Exchange (ETDEWEB)

    Murooka, Thomas T.; Rahbar, Ramtin [Division of Cellular and Molecular Biology, Toronto General Research Institute, University Health Network, Ont. (Canada); Department of Immunology, University of Toronto, Ont. (Canada); Fish, Eleanor N., E-mail: en.fish@utoronto.ca [Division of Cellular and Molecular Biology, Toronto General Research Institute, University Health Network, Ont. (Canada); Department of Immunology, University of Toronto, Ont. (Canada)

    2009-09-18

    The proliferative capacity of cancer cells is regulated by factors intrinsic to cancer cells and by secreted factors in the microenvironment. Here, we investigated the proto-oncogenic potential of the chemokine receptor, CCR5, in MCF-7 breast cancer cell lines. At physiological levels, CCL5, a ligand for CCR5, enhanced MCF-7.CCR5 proliferation. Treatment with the mTOR inhibitor, rapamycin, inhibited this CCL5-inducible proliferation. Because mTOR directly modulates mRNA translation, we investigated whether CCL5 activation of CCR5 leads to increased translation. CCL5 induced the formation of the eIF4F translation initiation complex through an mTOR-dependent process. Indeed, CCL5 initiated mRNA translation, shown by an increase in high-molecular-weight polysomes. Specifically, we show that CCL5 mediated a rapid up-regulation of protein expression for cyclin D1, c-Myc and Dad-1, without affecting their mRNA levels. Taken together, we describe a mechanism by which CCL5 influences translation of rapamycin-sensitive mRNAs, thereby providing CCR5-positive breast cancer cells with a proliferative advantage.

  9. Moringa oleifera Gold Nanoparticles Modulate Oncogenes, Tumor Suppressor Genes, and Caspase-9 Splice Variants in A549 Cells.

    Science.gov (United States)

    Tiloke, Charlette; Phulukdaree, Alisa; Anand, Krishnan; Gengan, Robert M; Chuturgoon, Anil A

    2016-10-01

    Gold nanoparticles (AuNP's) facilitate cancer cell recognition and can be manufactured by green synthesis using nutrient rich medicinal plants such as Moringa oleifera (MO). Targeting dysregulated oncogenes and tumor suppressor genes is crucial for cancer therapeutics. We investigated the antiproliferative effects of AuNP synthesized from MO aqueous leaf extracts (MLAuNP ) in A549 lung and SNO oesophageal cancer cells. A one-pot green synthesis technique was used to synthesise MLAuNP . A549, SNO cancer cells and normal peripheral blood mononuclear cells (PBMCs) were exposed to MLAuNP and CAuNP to evaluate cytotoxicity (MTT assay); apoptosis was measured by phosphatidylserine (PS) externalization, mitochondrial depolarization (ΔΨm) (flow cytometry), caspase-3/7, -9 activity, and ATP levels (luminometry). The mRNA expression of c-myc, p53, Skp2, Fbw7α, and caspase-9 splice variants was determined using qPCR, while relative protein expression of c-myc, p53, SRp30a, Bax, Bcl-2, Smac/DIABLO, Hsp70, and PARP-1 were determined by Western blotting. MLAuNP and CAuNP were not cytotoxic to PBMCs, whilst its pro-apoptotic properties were confirmed in A549 and SNO cells. MLAuNP significantly increased caspase activity in SNO cells while MLAuNP significantly increased PS externalization, ΔΨm, caspase-9, caspase-3/7 activities, and decreased ATP levels in A549 cells. Also, p53 mRNA and protein levels, SRp30a (P = 0.428), Bax, Smac/DIABLO and PARP-1 24 kDa fragment levels were significantly increased. Conversely, MLAuNP significantly decreased Bcl-2, Hsp70, Skp2, Fbw7α, c-myc mRNA, and protein levels and activated alternate splicing with caspase-9a splice variant being significantly increased. MLAuNP possesses antiproliferative properties and induced apoptosis in A549 cells by activating alternate splicing of caspase-9. J. Cell. Biochem. 117: 2302-2314, 2016. © 2016 Wiley Periodicals, Inc.

  10. mRNA detection in living cell using phosphorothioate-modified molecular beacon

    Institute of Scientific and Technical Information of China (English)

    TANG HongXing; YANG XiaoHai; WANG KeMin; TAN WeiHong; LI Wei

    2009-01-01

    In this study, GFP mRNA in COS-7 cell and GFP-transfected COS-7 cell was detected in real time using phosphorothioate-modified molecular beacon based on living cell imaging method. Results showed that phosphorothioate-modified molecular beacon still kept the advantages of molecular beacon, such as, excellent selectivity, high sensitivity, and no separation detection. In addition, this modification could significantly increase the nuclease resistance of molecular beacon. Phosphorothioate-modified molecular beacon can efficiently reduce the false positive signal and improve the accuracy of living cell mRNA detection.

  11. Oncogenic BRAF regulates melanoma proliferation through the lineage specific factor MITF.

    Directory of Open Access Journals (Sweden)

    Claudia Wellbrock

    Full Text Available The Microphthalmia-associated transcription factor (MITF is an important regulator of cell-type specific functions in melanocytic cells. MITF is essential for the survival of pigmented cells, but whereas high levels of MITF drive melanocyte differentiation, lower levels are required to permit proliferation and survival of melanoma cells. MITF is phosphorylated by ERK, and this stimulates its activation, but also targets it for degradation through the ubiquitin-proteosome pathway, coupling MITF degradation to its activation. We have previously shown that because ERK is hyper-activated in melanoma cells in which BRAF is mutated, the MITF protein is constitutively down-regulated. Here we describe another intriguing aspect of MITF regulation by oncogenic BRAF in melanoma cells. We show oncogenic BRAF up-regulates MITF transcription through ERK and the transcription factor BRN2 (N-Oct3. In contrast, we show that in melanocytes this pathway does not exist because BRN2 is not expressed, demonstrating that MITF regulation is a newly acquired function of oncogenic BRAF that is not performed by the wild-type protein. Critically, in melanoma cells MITF is required downstream of oncogenic BRAF because it regulates expression of key cell cycle regulatory proteins such as CDK2 and CDK4. Wild-type BRAF does not regulate this pathway in melanocytes. Thus, we show that oncogenic BRAF exerts exquisite control over MITF on two levels. It downregulates the protein by stimulating its degradation, but then counteracts this by increasing transcription through BRN2. Our data suggest that oncogenic BRAF plays a critical role in regulating MITF expression to ensure that its protein levels are compatible with proliferation and survival of melanoma cells. We propose that its ability to appropriate the regulation of this critical factor explains in part why BRAF is such a potent oncogene in melanoma.

  12. Relationship between expression of somatostatin receptors subtype 2 mRNA and estrogen and progesterone receptors in breast cancer

    Institute of Scientific and Technical Information of China (English)

    曾希志; 姚榛祥

    2003-01-01

    Objectives To observe the expression of somatostatin receptor subtype 2 (SSTR2) mRNA, and investigate the relationship between the expression of SSTR2 mRNA and the expressions of estrogen and progesterone receptors (ERs and PRs) in benign and malignant breast tissues.Methods Samples from a total of 23 breast carcinomas, 16 mammary hyperplasias, and 9 mammary fibroadenomas were analyzed. SSTR2 mRNA expression was examined by in situ hybridization using multiphase oligoprobes. ER and PR expressions were detected by immunohistochemical staining. A computerized image analysis system was utilized to estimate the relative content of SSTR2 mRNA.Results The rate of expression (87.0%) and relative content (0.47) of SSTR2 mRNA in breast cancer were higher than those in benign breast tissue (64%,0.26) (P<0.05). SSTR2 mRNA expression was closely correlated with ER and PR expressions in breast cancer (P<0.05). SSTR2 mRNA was also positively correlated with ER expression in benign breast tissues.Conclusions SSTR2 mRNA expression is higher or in benign breast tissues than in malignant ones. There is a significant positive correlation between SSTR2 mRNA and ER and PR expressions. Combined antiestrogen and somatostatin analogue in treatment of ER-positive breast cancers should be further investigated.

  13. TEAD1/4 exerts oncogenic role and is negatively regulated by miR-4269 in gastric tumorigenesis.

    Science.gov (United States)

    Zhou, Y; Huang, T; Zhang, J; Wong, C C; Zhang, B; Dong, Y; Wu, F; Tong, J H M; Wu, W K K; Cheng, A S L; Yu, J; Kang, W; To, K F

    2017-07-31

    TEA domain (TEAD) transcription factors are key components of the Hippo-YAP1 signaling pathway, but their functional role and regulatory mechanisms remain unclear. This study aims to comprehensively explore the expression pattern and functional role of TEAD family in gastric carcinogenesis and investigate its regulation by microRNAs (miRNAs). The mRNA and protein expression of TEAD family were examined by quantitative reverse transcription-PCR (qRT-PCR) and western blot. Their functional roles were determined by in vitro and in vivo studies. The clinicopathological association of TEAD4 in gastric cancer (GC) was studied using immunohistochemistry on tissue microarray. The prediction of miRNAs, which potentially target TEAD1/4, was performed by TargetScan and miRDB. The regulation of TEAD1/4 by miRNAs was confirmed by qRT-PCR, western blot and luciferase assays. TEAD1/4 were overexpressed in GC cell lines and primary GC tissues. Knockdown of TEAD1/4 induced a significant anticancer effect in vitro and in vivo. TEAD1 was confirmed to be a direct target of miR-377-3p and miR-4269, while TEAD4 was negatively regulated by miR-1343-3p and miR-4269. Among them, miR-4269 was the most effective inhibitor of TEAD1/4. Ectopic expression of these miRNAs substantiated their tumor-suppressive effects. In primary GC tumors, downregulation of miR-4269 was associated with poor disease-specific survival and showed a negative correlation with TEAD4. TEAD1 and TEAD4 are oncogenic factors, whose aberrant activation are, in part, mediated by the silence of miR-377-3p, miR-1343-3p and miR-4269. For the first time, the nuclear accumulated TEAD4 and downregulated miR-4269 are proposed to serve as novel prognostic biomarkers in GC.Oncogene advance online publication, 31 July 2017; doi:10.1038/onc.2017.257.

  14. The oncogenic action of ionizing radiation on rat skin

    Energy Technology Data Exchange (ETDEWEB)

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

    1992-01-01

    The multistage theory of carcinogenesis specifies that cells progress to cancer through a series of discrete, irreversible genetic alterations, but data on radiation-induced cancer incidence in rat skin suggests that an intermediate repairable alteration may occur. Data are presented on cancer induction in rat skin exposed to an electron beam (LET=0.34 keV/[mu]), a neon ion beam (LET=45) or an argon ion beam (LET=125). The rats were observed for tumors at least 78 weeks with squamous and basal cell carcinomas observed. The total cancer yield was fitted by the quadratic equation, and the equation parameters were estimated by linear regression for each type of radiation. Analysis of the DNA from the electron-induced carcinomas indicated that K-ras and/or c-myc oncogenes were activated. In situ hybridization indicated that the cancers contain subpopulations of cells with differing amounts of c-myc and H-ras amplification. The results are consistent with the idea that ionizing radiation produces stable, carcinogenically relevant lesions via 2 repairable events at low LET and via a non-repairable linked event pathway at high LET; either pathway may advance the cell by 1 stage. The proliferative response of rat epidermis following exposure to ionizing radiation was quantified by injection of [sup 14]C-thymidine. The return of these cells to S-phase a second time was detected by a second label ([sup 3]H). When the labeled cells were in G1-phase, the dorsal skin was irradiated with X-rays. All labeling indices were determined. The [sup 14]C labeling index was constant and unaffected by the radiation. The proportion of all cells entering S-phase averaged 3.5% at 18 hr and increased after 44, 52 and 75 hr to average levels of 11.8%, 5. 3%, and 6.6% at 0, 10 and 25 Gy respectively. The proportion of S-phase cells labeled with [sup 14]C increased after 42 hr and remained relatively constant thereafter.

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

    DEFF Research Database (Denmark)

    Sap, J; Muñoz, A; Schmitt, J

    1989-01-01

    Several recent observations, such as the identification of the cellular homologue of the v-erb-A oncogene as a thyroid-hormone receptor, have strongly implicated nuclear oncogenes in transcriptional control mechanisms. The v-erb-A oncogene blocks the differentiation of erythroid cells, and changes......-erb-A protein negatively interferes with normal transcriptional-control mechanisms, and that amino-acid substitutions have altered its DNA-binding properties....

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

    Directory of Open Access Journals (Sweden)

    Singh Tej P

    2011-07-01

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

  17. Dysfunctional oxidative phosphorylation makes malignant melanoma cells addicted to glycolysis driven by the V600EBRAF oncogene

    DEFF Research Database (Denmark)

    Hall, Arnaldur; Meyle, Kathrine Damm; Lange, Marina Krarup

    2013-01-01

    Oncogene addiction describes how cancer cells exhibit dependence on single oncogenes to escape apoptosis and senescence. While oncogene addiction constitutes the basis for new cancer treatment strategies targeting individual kinases and pathways activated by oncogenic mutations, the biochemical...... basis for this addiction is largely unknown. Here we provide evidence for a metabolic rationale behind the addiction to V600EBRAF in two malignant melanoma cell lines. Both cell lines display a striking addiction to glycolysis due to underlying dysfunction of oxidative phosphorylation (OXPHOS). Notably...

  18. High frequency of the HRAS oncogene codon 12 mutation in Macedonian patients with urinary bladder cancer

    Directory of Open Access Journals (Sweden)

    Sasho Panov

    2004-01-01

    Full Text Available Point mutations at codon 12 of the HRAS (v-Ha-ras Harvey rat sarcoma viral oncogene homolog oncogene are one of the best defined and widely studied molecular genetic events in transitional cell carcinoma (TCC of the urinary bladder. The aim of this study was to use the polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP analysis of paraffin-embedded tissue-derived DNA to determine the frequency of the HRAS oncogene G ->T codon 12 mutation in TCC patients being treated at the University Urology Clinic in Skopje, Republic of Macedonia. DNA isolated from paraffin-embedded tissue (PET surgically removed TCC specimens of 62 (81.58% out of 76 patients were successfully amplified, the remaining 14 (18.42% showing compromised DNA integrity. The codon 12 mutation of the HRAS oncogene was found in 24 (38.71% out of 62 successfully tested TCC urinary bladder samples. No significant relationship between the mutation frequency and the histopathological grade of tumor differentiation was detected (chi² = 0.044; p = 0.978. The relatively high frequency of mutations found in our study was comparable with some of the previously reported data obtained by this and/or other PCR-based methods. This highly sensitive and specific PCR-RFLP analysis was demonstrated to be a suitable method for the detection of mutations at codon 12 of the HRAS oncogene in PET samples of urinary bladder TCC.

  19. Limited Role of Murine ATM in Oncogene-Induced Senescence and p53-Dependent Tumor Suppression

    Science.gov (United States)

    Martinez-Pastor, Barbara; Ortega-Molina, Ana; Soria, Rebeca; Collado, Manuel; Fernandez-Capetillo, Oscar; Serrano, Manuel

    2009-01-01

    Recent studies in human fibroblasts have provided a new general paradigm of tumor suppression according to which oncogenic signaling produces DNA damage and this, in turn, results in ATM/p53-dependent cellular senescence. Here, we have tested this model in a variety of murine experimental systems. Overexpression of oncogenic Ras in murine fibroblasts efficiently induced senescence but this occurred in the absence of detectable DNA damage signaling, thus suggesting a fundamental difference between human and murine cells. Moreover, lung adenomas initiated by endogenous levels of oncogenic K-Ras presented abundant senescent cells, but undetectable DNA damage signaling. Accordingly, K-Ras-driven adenomas were also senescent in Atm-null mice, and the tumorigenic progression of these lesions was only modestly accelerated by Atm-deficiency. Finally, we have examined chemically-induced fibrosarcomas, which possess a persistently activated DNA damage response and are highly sensitive to the activity of p53. We found that the absence of Atm favored genomic instability in the resulting tumors, but did not affect the persistent DNA damage response and did not impair p53-dependent tumor suppression. All together, we conclude that oncogene-induced senescence in mice may occur in the absence of a detectable DNA damage response. Regarding murine Atm, our data suggest that it plays a minor role in oncogene-induced senescence or in p53-dependent tumor suppression, being its tumor suppressive activity probably limited to the maintenance of genomic stability. PMID:19421407

  20. Oncofuse: a computational framework for the prediction of the oncogenic potential of gene fusions.

    Science.gov (United States)

    Shugay, Mikhail; Ortiz de Mendíbil, Iñigo; Vizmanos, José L; Novo, Francisco J

    2013-10-15

    Gene fusions resulting from chromosomal aberrations are an important cause of cancer. The complexity of genomic changes in certain cancer types has hampered the identification of gene fusions by molecular cytogenetic methods, especially in carcinomas. This is changing with the advent of next-generation sequencing, which is detecting a substantial number of new fusion transcripts in individual cancer genomes. However, this poses the challenge of identifying those fusions with greater oncogenic potential amid a background of 'passenger' fusion sequences. In the present work, we have used some recently identified genomic hallmarks of oncogenic fusion genes to develop a pipeline for the classification of fusion sequences, namely, Oncofuse. The pipeline predicts the oncogenic potential of novel fusion genes, calculating the probability that a fusion sequence behaves as 'driver' of the oncogenic process based on features present in known oncogenic fusions. Cross-validation and extensive validation tests on independent datasets suggest a robust behavior with good precision and recall rates. We believe that Oncofuse could become a useful tool to guide experimental validation studies of novel fusion sequences found during next-generation sequencing analysis of cancer transcriptomes. Oncofuse is a naive Bayes Network Classifier trained and tested using Weka machine learning package. The pipeline is executed by running a Java/Groovy script, available for download at www.unav.es/genetica/oncofuse.html.

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

    Directory of Open Access Journals (Sweden)

    Alejo Efeyan

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

  2. LEO1 is regulated by PRL-3 and mediates its oncogenic properties in acute myelogenous leukemia.

    Science.gov (United States)

    Chong, Phyllis S Y; Zhou, Jianbiao; Cheong, Lip-Lee; Liu, Shaw-Cheng; Qian, Jingru; Guo, Tiannan; Sze, Siu Kwan; Zeng, Qi; Chng, Wee Joo

    2014-06-01

    PRL-3, an oncogenic dual-specificity phosphatase, is overexpressed in 50% of acute myelogenous leukemia (AML) and associated with poor survival. We found that stable expression of PRL-3 confers cytokine independence and growth advantage of AML cells. However, how PRL-3 mediates these functions in AML is not known. To comprehensively screen for PRL3-regulated proteins in AML, we performed SILAC-based quantitative proteomics analysis and discovered 398 significantly perturbed proteins after PRL-3 overexpression. We show that Leo1, a component of RNA polymerase II-associated factor (PAF) complex, is a novel and important mediator of PRL-3 oncogenic activities in AML. We described a novel mechanism where elevated PRL-3 protein increases JMJD2C histone demethylase occupancy on Leo1 promoter, thereby reducing the H3K9me3 repressive signals and promoting Leo1 gene expression. Furthermore, PRL-3 and Leo1 levels were positively associated in AML patient samples (N=24; PPRL-3 oncogenic phenotypes in AML. Loss of Leo1 leads to destabilization of the PAF complex and downregulation of SOX2 and SOX4, potent oncogenes in myeloid transformation. In conclusion, we identify an important and novel mechanism by which PRL-3 mediates its oncogenic function in AML.

  3. Viral Oncogenes, Noncoding RNAs, and RNA Splicing in Human Tumor Viruses

    Directory of Open Access Journals (Sweden)

    Zhi-Ming Zheng

    2010-01-01

    Full Text Available Viral oncogenes are responsible for oncogenesis resulting from persistent virus infection. Although different human tumor viruses express different viral oncogenes and induce different tumors, their oncoproteins often target similar sets of cellular tumor suppressors or signal pathways to immortalize and/or transform infected cells. Expression of the viral E6 and E7 oncogenes in papillomavirus, E1A and E1B oncogenes in adenovirus, large T and small t antigen in polyomavirus, and Tax oncogene in HTLV-1 are regulated by alternative RNA splicing. However, this regulation is only partially understood. DNA tumor viruses also encode noncoding RNAs, including viral microRNAs, that disturb normal cell functions. Among the determined viral microRNA precursors, EBV encodes 25 from two major clusters (BART and BHRF1, KSHV encodes 12 from a latent region, human polyomavirus MCV produce only one microRNA from the late region antisense to early transcripts, but HPVs appears to produce no viral microRNAs.

  4. Modulating the strength and threshold of NOTCH oncogenic signals by mir-181a-1/b-1.

    Directory of Open Access Journals (Sweden)

    Rita Fragoso

    Full Text Available Oncogenes, which are essential for tumor initiation, development, and maintenance, are valuable targets for cancer therapy. However, it remains a challenge to effectively inhibit oncogene activity by targeting their downstream pathways without causing significant toxicity to normal tissues. Here we show that deletion of mir-181a-1/b-1 expression inhibits the development of Notch1 oncogene-induced T cell acute lymphoblastic leukemia (T-ALL. mir-181a-1/b-1 controls the strength and threshold of Notch activity in tumorigenesis in part by dampening multiple negative feedback regulators downstream of NOTCH and pre-T cell receptor (TCR signaling pathways. Importantly, although Notch oncogenes utilize normal thymic progenitor cell genetic programs for tumor transformation, comparative analyses of mir-181a-1/b-1 function in normal thymocyte and tumor development demonstrate that mir-181a-1/b-1 can be specifically targeted to inhibit tumor development with little toxicity to normal development. Finally, we demonstrate that mir-181a-1/b-1, but not mir-181a-2b-2 and mir-181-c/d, controls the development of normal thymic T cells and leukemia cells. Together, these results illustrate that NOTCH oncogene activity in tumor development can be selectively inhibited by targeting the molecular networks controlled by mir-181a-1/b-1.

  5. Regulation of autophagy and chloroquine sensitivity by oncogenic RAS in vitro is context-dependent.

    Science.gov (United States)

    Morgan, Michael J; Gamez, Graciela; Menke, Christina; Hernandez, Ariel; Thorburn, Jacqueline; Gidan, Freddi; Staskiewicz, Leah; Morgan, Shellie; Cummings, Christopher; Maycotte, Paola; Thorburn, Andrew

    2014-10-01

    Chloroquine (CQ) is an antimalarial drug and late-stage inhibitor of autophagy currently FDA-approved for use in the treatment of rheumatoid arthritis and other autoimmune diseases. Based primarily on its ability to inhibit autophagy, CQ and its derivative, hydroxychloroquine, are currently being investigated as primary or adjuvant therapy in multiple clinical trials for cancer treatment. Oncogenic RAS has previously been shown to regulate autophagic flux, and cancers with high incidence of RAS mutations, such as pancreatic cancer, have been described in the literature as being particularly susceptible to CQ treatment, leading to the hypothesis that oncogenic RAS makes cancer cells dependent on autophagy. This autophagy "addiction" suggests that the mutation status of RAS in tumors could identify patients who would be more likely to benefit from CQ therapy. Here we show that RAS mutation status itself is unlikely to be beneficial in such a patient selection because oncogenic RAS does not always promote autophagy addiction. Moreover, oncogenic RAS can have opposite effects on both autophagic flux and CQ sensitivity in different cells. Finally, for any given cell type, the positive or negative effect of oncogenic RAS on autophagy does not necessarily predict whether RAS will promote or inhibit CQ-mediated toxicity. Thus, although our results confirm that different tumor cell lines display marked differences in how they respond to autophagy inhibition, these differences can occur irrespective of RAS mutation status and, in different contexts, can either promote or reduce chloroquine sensitivity of tumor cells.

  6. The PEI-introduced CS shell/PMMA core nanoparticle for silencing the expression of E6/E7 oncogenes in human cervical cells.

    Science.gov (United States)

    Saengkrit, Nattika; Sanitrum, Phakorn; Woramongkolchai, Noppawan; Saesoo, Somsak; Pimpha, Nuttaporn; Chaleawlert-Umpon, Saowaluk; Tencomnao, Tewin; Puttipipatkhachorn, Satit

    2012-10-15

    In this study, we examined the potential of cationic nanoparticle - polyethyleneimine-introduced chitosan shell/poly (methyl methacrylate) core nanoparticles (CS-PEI) for siRNA delivery. Initially, DNA delivery was performed to validate the capability of CS-PEI for gene delivery in the human cervical cancer cell line, SiHa. siRNA delivery were subsequently carried out to evaluate the silencing effect on targeted E6 and E7 oncogenes. Physicochemical properties including size, zeta potential and morphology of CS-PEI/DNA and CS-PEI/siRNA complexes, were analyzed. The surface charges and sizes of the complexes were observed at different N/P ratios. The hydrodynamic sizes of the CS-PEI/DNA and CS-PEI/siRNA were approximately 300-400 and 400-500nm, respectively. Complexes were positively charged depending on the amount of added CS-PEI. AFM images revealed the mono-dispersed and spherical shapes of the complexes. Gel retardation assay confirmed that CS-PEI nanoparticles completely formed complexes with DNA and siRNA at a N/P ratio of 1.6. For DNA transfection, CS-PEI provided the highest transfection result. Localization of siRNA delivered through CS-PEI was confirmed by differential interference contrast (DIC) confocal imaging. The silencing effect of siRNA specific to HPV 16 E6/E7 oncogene was examined at 18 and 24h post-transfection. The results demonstrated the capacity of CS-PEI to suppress the expression of HVP oncogenes. Copyright © 2012 Elsevier Ltd. All rights reserved.

  7. Anesthesia for euthanasia influences mRNA expression in healthy mice and after traumatic brain injury.

    Science.gov (United States)

    Staib-Lasarzik, Irina; Kriege, Oliver; Timaru-Kast, Ralph; Pieter, Dana; Werner, Christian; Engelhard, Kristin; Thal, Serge C

    2014-10-01

    Tissue sampling for gene expression analysis is usually performed under general anesthesia. Anesthetics are known to modulate hemodynamics, receptor-mediated signaling cascades, and outcome parameters. The present study determined the influence of anesthetic paradigms typically used for euthanization and tissue sampling on cerebral mRNA expression in mice. Naïve mice and animals with acute traumatic brain injury induced by controlled cortical impact (CCI) were randomized to the following euthanasia protocols (n=10-11/group): no anesthesia (NA), 1 min of 4 vol% isoflurane in room air (ISO), 3 min of a combination of 5 mg/kg midazolam, 0.05 mg/kg fentanyl, and 0.5 mg/kg medetomidine intraperitoneally (COMB), or 3 min of 360 mg/kg chloral hydrate intraperitoneally (CH). mRNA expression of actin-1-related gene (Act1), FBJ murine osteosarcoma viral oncogene homolog B (FosB), tumor necrosis factor alpha (TNFα), heat shock protein beta-1 (HspB1), interleukin (IL)-6, tight junction protein 1 (ZO-1), IL-1ß, cyclophilin A, micro RNA 497 (miR497), and small cajal body-specific RNA 17 were determined by real-time polymerase chain reaction (PCR) in hippocampus samples. In naïve animals, Act1 expression was downregulated in the CH group compared with NA. FosB expression was downregulated in COMB and CH groups compared with NA. CCI reduced Act1 and FosB expression, whereas HspB1 and TNFα expression increased. After CCI, HspB1 expression was significantly higher in ISO, COMB, and CH groups, and TNFα expression was elevated in ISO and COMB groups. MiR497, IL-6, and IL-1ß were upregulated after CCI but not affected by anesthetics. Effects were independent of absolute mRNA copy numbers. The data demonstrate that a few minutes of anesthesia before tissue sampling are sufficient to induce immediate mRNA changes, which seem to predominate in the early-regulated gene cluster. Anesthesia-related effects on gene expression might explain limited reproduciblity of real

  8. Prevalence of type-specific oncogenic human papillomavirus infection assessed by HPV E6/E7 mRNA among women with high-grade cervical lesions

    Directory of Open Access Journals (Sweden)

    Hye-young Wang

    2015-08-01

    Conclusions: These results suggest that the determination of specific HPV genotypes is very important for evaluating the potential impact of preventive measures, including the use of prophylactic vaccines, on reducing the burden of cervical cancer.

  9. Detection of MDR1 mRNA expression with optimized gold nanoparticle beacon

    Science.gov (United States)

    Zhou, Qiumei; Qian, Zhiyu; Gu, Yueqing

    2016-03-01

    MDR1 (multidrug resistance gene) mRNA expression is a promising biomarker for the prediction of doxorubicin resistance in clinic. However, the traditional technical process in clinic is complicated and cannot perform the real-time detection mRNA in living single cells. In this study, the expression of MDR1 mRNA was analyzed based on optimized gold nanoparticle beacon in tumor cells. Firstly, gold nanoparticle (AuNP) was modified by thiol-PEG, and the MDR1 beacon sequence was screened and optimized using a BLAST bioinformatics strategy. Then, optimized MDR1 molecular beacons were characterized by transmission electron microscope, UV-vis and fluorescence spectroscopies. The cytotoxicity of MDR1 molecular beacon on L-02, K562 and K562/Adr cells were investigated by MTT assay, suggesting that MDR1 molecular beacon was low inherent cytotoxicity. Dark field microscope was used to investigate the cellular uptake of hDAuNP beacon assisted with ultrasound. Finally, laser scanning confocal microscope images showed that there was a significant difference in MDR1 mRNA expression in K562 and K562/Adr cells, which was consistent with the results of q-PCR measurement. In summary, optimized MDR1 molecular beacon designed in this study is a reliable strategy for detection MDR1 mRNA expression in living tumor cells, and will be a promising strategy for in guiding patient treatment and management in individualized medication.

  10. Radiosensitivity of small-cell lung cancer xenografts compared with activity of c-myc, N-myc, L-myc, c-raf-1 and K-ras proto-oncogenes

    DEFF Research Database (Denmark)

    Rygaard, K; Slebos, R J; Spang-Thomsen, M

    1991-01-01

    than CPH-54B, while, with respect to the 3 GLC tumours examined, GLC-16 was most sensitive, followed by GLC-14 and GLC-19. The CPH tumours expressed similar amounts of c-myc and c-raf-1 mRNA, and neither expressed N-myc or L-myc. GLC-14 expressed N-myc and c-raf-1 mRNA but no c-myc. GLC-16 and GLC-19...... expressed identical amounts of c-raf-1 and high levels of c-myc mRNA, but neither expressed N-myc or L-myc. None of the tumours was mutated at codon 12 or K-ras. Our results show that SCLC xenografts with different radiosensitivity may express identical amounts of some of the proto-oncogenes reported...... regrowth after single-dose irradiation. No long-term difference in expression of c-raf-1 or c-myc mRNA was detected between control tumours and tumours irradiated with 5 or 10 Gy....

  11. THOC5, a member of the mRNA export complex: a novel link between mRNA export machinery and signal transduction pathways in cell proliferation and differentiation.

    Science.gov (United States)

    Tran, Doan D H; Koch, Alexandra; Tamura, Teruko

    2014-01-10

    Cell growth, differentiation, and commitment to a restricted lineage are guided by a timely expressed set of growth factor/cytokine receptors and their down-stream transcription factor genes. Transcriptional control mechanisms of gene expression during differentiation have been mainly studied by focusing on the cis- and trans-elements in promoters however, the role of mRNA export machinery during differentiation has not been adequately examined. THO (Suppressors of the transcriptional defects of hpr1 delta by overexpression) complex 5 (THOC5) is a member of THO complex which is a subcomplex of the transcription/export complex (TREX). THOC5 is evolutionarily conserved in higher eukaryotes, however the exact roles of THOC5 in transcription and mRNA export are still unclear. In this review, we focus on recently uncovered aspects of the role of THOC5 in signal transduction induced by extracellular stimuli. THOC5 is phosphorylated by several protein kinases at multiple residues upon extracellular stimuli. These include stimulation with growth factors/cytokines/chemokines, or DNA damage reagents. Furthermore, THOC5 is a substrate for several oncogenic tyrosine kinases, suggesting that THOC5 may be involved in cancer development. Recent THOC5 knockout mouse data reveal that THOC5 is an essential element in the maintenance of stem cells and growth factor/cytokine-mediated differentiation/proliferation. Furthermore, depletion of THOC5 influences less than 1% of total mRNA export in the steady state, however it influences more than 90% of growth factor/cytokine induced genes. THOC5, thereby contributes to the 3' processing and/or export of immediate-early genes induced by extracellular stimuli. These studies bring new insight into the link between the mRNA export complex and immediate-early gene response. The data from these studies also suggest that THOC5 may be a useful tool for studying stem cell biology, for modifying the differentiation processes and for cancer therapy.

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

    CERN Document Server

    Kashyap, Amita; Babu M, Naresh

    2015-01-01

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

  13. Role of papillomavirus oncogenes in human cervical cancer: Transgenic animal studies

    Energy Technology Data Exchange (ETDEWEB)

    Griep, A.E.; Lambert, P.F. [Univ. of Wisconsin School of Medicine, Madison, WI (United States)

    1994-05-01

    Human papillomaviruses are believed to be etiologic agents for the majority of human cervical carcinoma, a common cancer that is a leading cause of death by cancer among women worldwide. In cervical carcinoma, a subset of papillomaviral genes, namely E6 and E7, are expressed. In vitro tissue culture studies indicate that HPV E6 and E7 are oncogenes, and that their oncogenicity is due in part to their capacity to inactivate cellular tumor suppressor genes. The behavior of E6 and E7 in vitro and the genetic evidence from analysis of human cancers suggest that the E6 and E7 genes play a significant role in the development of cervical cancer. This hypothesis is now being tested using animal models. In this review, we summarize our current knowledge of the oncogenicity of papillomavirus genes that has been generated through their study in transgenic mice. 82 refs., 4 figs., 1 tab.

  14. ONCOGENIC HUMAN PAPILLOMAVIRUS (HPV) INFECTIONS IN 18 TO 24 YEAR OLD FEMALE ONLINE DATERS

    Science.gov (United States)

    Barrere, Alexis; Stern, Joshua E.; Feng, Qinghua; Hughes, James P.; Winer, Rachel L.

    2015-01-01

    Background While risk factors for HPV infections in young women are well-defined, the risk associated with meeting male sex partners via the internet is unclear. Methods We analyzed cross-sectional data from 282 18-24-year old women who reported using Internet dating websites in the past year. Women were mailed vaginal self-sampling kits for PCR-based HPV genotyping (including 19 oncogenic types) and sexual behavior and health history questionnaires. Generalized linear models were used to evaluate risk factors for prevalent oncogenic HPV infections. Results 35% of women reported having met a male sex partner via the Internet in the past 6 months, and 42% reported a history of HPV vaccination. The prevalence of oncogenic HPV infection was 37%, and 9% of women tested positive for HPV-16 or HPV-18. Having met a male sex partner via the Internet in the past 6 months was not significantly associated with oncogenic HPV infection. In multivariate analyses, variables associated with an increased likelihood of oncogenic HPV infection included male partners in the past 6 months who were reported to have ≥1 concurrent partnership (adjusted prevalence ratio [aPR]=1.51,95%CI:1.11-2.06) and not always using condoms with male partners in the past 6 months (aPR=1.86,95%CI:1.05-3.30). Self-reporting a history of receiving ≥1 dose of HPV vaccine was inversely associated with testing positive for HPV-16 or HPV-18 (aPR=0.39,95%CI:0.16–0.97). Conclusions While measures of recent sexual behavior were associated with prevalent oncogenic HPV infection, male partners met online were not associated with an increased likelihood of infection in this cohort of young women. PMID:26267875

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

    Directory of Open Access Journals (Sweden)

    Rolando ePerez

    2013-04-01

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

  16. [Oncogenic human papillomaviruses in extra-genital Bowen disease revealed by in situ hybridization].

    Science.gov (United States)

    Derancourt, C; Mougin, C; Chopard Lallier, M; Coumes-Marquet, S; Drobacheff, C; Laurent, R

    2001-01-01

    The association between mucosal oncogenic human papillomaviruses (HPV) and bowenoid papulosis or genital Bowen's disease is well documented. In contrast this association with extra-genital Bowen's disease is poorly studied. The aim of this study was to detect oncogenic (16/18, 31/33/51) and non oncogenic (8/11) mucosal HPV using a in situ hybridization method in 28 skin biopsy specimens of extra-genital Bowen's disease. Twenty-eight cases of extra-genital Bowen's disease seen in the period 1990-96 in the Dermatology department were included: 19 women and 9 men (mean age: 72 years). Bowen's disease locations were: hands and feet (8 cases), limbs (11 cases), face (8 cases), trunk (1 case). Blinded histopathologic examination confirmed the diagnosis of Bowen's disease and signs of HPV infection (koilocytosis). In situ hybridization was performed using three biotinylated probes detecting HPV types 6/11, 16/18, 31/33/51. Oncogenic HPV genoma was detected in 8 skin samples (28.6 p. 100). In all these cases, 16/18 probe was positive and in two cases, both 16/18 and 31/33/51 probes were positive; 4/8 Bowen's diseases of the extremities were positive for HPV. Koilocytes were found in 6/8 of skin samples with positive HPV detection. Mucosal oncogenic HPV are detected by in situ hybridization in 28.6 p. 100 of extra-genital Bowen's disease. In situ hybridization is an easier technique than Southern-Blot hybridization which is the gold standard. Five studies reported similar results and three studies reported different results that we discuss. A precise understanding of oncogenic HPV implication in the development of extra-genital Bowen's disease could lead to the development of new therapeutic strategies (topical cidofovir or imiquimod).

  17. Characterization of TRPS1 and ERAS as oncogenes implicated in breast cancer

    Energy Technology Data Exchange (ETDEWEB)

    Lopez Gonzalez, L.

    2015-07-01

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

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

    DEFF Research Database (Denmark)

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

    2014-01-01

    fibroblasts. This screen led to the identification of miR-378a-5p and in addition several other miRNAs that have previously been shown to play a role in senescence. We show that ectopic expression of miR-378a-5p reduces the expression of several senescence markers, including p16INK4A and senescence......-associated β-galactosidase. Moreover, cells with ectopic expression of miR-378a-5p retain proliferative capacity even in the presence of an activated Braf oncogene. Finally, we identified several miR-378a-5p targets in diploid fibroblasts that might explain the mechanism by which the microRNA can delay OIS. We...... speculate that miR-378a-5p might positively influence tumor formation by delaying OIS, which is consistent with a known pro-oncogenic function of this microRNA....

  19. The antiviral drug ribavirin does not mimic the 7-methylguanosine moiety of the mRNA cap structure in vitro.

    Science.gov (United States)

    Westman, Belinda; Beeren, Lisa; Grudzien, Ewa; Stepinski, Janusz; Worch, Remigiusz; Zuberek, Joanna; Jemielity, Jacek; Stolarski, Ryszard; Darzynkiewicz, Edward; Rhoads, Robert E; Preiss, Thomas

    2005-10-01

    The eukaryotic initiation factor eIF4E binds the mRNA 5' cap structure and has a central role during translational initiation. eIF4E and the mechanisms to control its activity have oncogenic properties and thus have become targets for anticancer drug development. A recent study (Kentsis et al. 2004) presented evidence that the antiviral nucleoside ribavirin and its phosphorylated derivatives were structural mimics of the mRNA cap, high-affinity ligands for eIF4E, and potent repressors of eIF4E-mediated cell transformation and tumor growth. Based on these findings, we tested ribavirin, ribavirin triphosphate (RTP), and the dinucleotide RpppG for their ability to inhibit translation in vitro. Surprisingly, the ribavirin-based compounds did not affect translation at concentrations where canonical cap analogs efficiently block cap-dependent translation. Using a set of reporter mRNAs that are translated via either cap-dependent or viral internal ribosome entry sites (IRES)-dependent initiation, we found that these ribavirin-containing compounds did inhibit translation at high (millimolar) concentrations, but there was no correlation of this inhibition with an eIF4E requirement for translation. The addition of a ribavirin-containing cap to mRNA did not stimulate translation. Fluorescence titration experiments with eIF4E and the nuclear cap-binding complex CBC indicated affinities for RTP and RpppG that were two to four orders of magnitude lower than those of m(7)GTP and m(7)GpppG. We conclude that, at least with respect to translation, ribavirin does not act in vitro as a functional mimic of the mRNA cap.

  20. Cadmium Activates Multiple Signaling Pathways That Coordinately Stimulate Akt Activity to Enhance c-Myc mRNA Stability.

    Directory of Open Access Journals (Sweden)

    Jia-Shiuan Tsai

    Full Text Available Cadmium is a known environmental carcinogen. Exposure of Cd leads to the activation of several proto-oncogenes in cells. We investigated here the mechanism of c-Myc expression in hepatic cells under Cd treatment. The c-Myc protein and mRNA levels increased in dose- and time-dependent manners in HepG2 cells with Cd treatment. This increase was due to an increase in c-Myc mRNA stability. To explore the mechanism involved in enhancing the mRNA stability, several cellular signaling factors that evoked by Cd treatment were analyzed. PI3K, p38, ERK and JNK were activated by Cd. However, ERK did not participate in the Cd-induced c-Myc expression. Further analysis revealed that mTORC2 was a downstream factor of p38. PI3K, JNK and mTORC2 coordinately activated Akt. Akt was phosphorylated at Thr450 in the untreated cells. Cd treatment led to additional phosphorylation at Thr308 and Ser473. Blocking any of the three signaling factors resulted in the reduction of phosphorylation level at all three Akt sites. The activated Akt phosphorylated Foxo1 and allowed the modified protein to translocate into the cytoplasm. We conclude that Cd-induced accumulation of c-Myc requires the activation of several signaling pathways. The signals act coordinately for Akt activation and drive the Foxo1 from the nucleus to the cytoplasm. Reduction of Foxo1 in the nucleus reduces the transcription of its target genes that may affect c-Myc mRNA stability, resulting in a higher accumulation of the c-Myc proteins.

  1. Regulation of Proto-Oncogenic Dbl by Chaperone-Controlled, Ubiquitin-Mediated Degradation▿

    OpenAIRE

    Kamynina, Elena; Kauppinen, Krista; Duan, Faping; Muakkassa, Nora; Manor, Danny

    2006-01-01

    The dbl proto-oncogene product is a prototype of a growing family of guanine nucleotide exchange factors (GEFs) that stimulate the activation of small GTP-binding proteins from the Rho family. Mutations that result in the loss of proto-Dbl's amino terminus produce a variant with constitutive GEF activity and high oncogenic potential. Here, we show that proto-Dbl is a short-lived protein that is kept at low levels in cells by efficient ubiquitination and degradation. The cellular fate of proto...

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

    Energy Technology Data Exchange (ETDEWEB)

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

    1999-02-01

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

  3. LTβR signalling preferentially accelerates oncogenic AKT-initiated liver tumours

    Science.gov (United States)

    Scarzello, Anthony J; Jiang, Qun; Back, Timothy; Dang, Hien; Hodge, Deborah; Hanson, Charlotte; Subleski, Jeffrey; Weiss, Jonathan M; Stauffer, Jimmy K; Chaisaingmongkol, Jitti; Rabibhadana, Siritida; Ruchirawat, Mathuros; Ortaldo, John; Wang, Xin Wei; Norris, Paula S; Ware, Carl F; Wiltrout, Robert H

    2016-01-01

    Objectives The relative contributions of inflammatory signalling and sequential oncogenic dysregulation driving liver cancer pathogenesis remain incompletely understood. Lymphotoxin-β receptor (LTβR) signalling is critically involved in hepatitis and liver tumorigenesis. Therefore, we explored the interdependence of inflammatory lymphotoxin signalling and specific oncogenic pathways in the progression of hepatic cancer. Design Pathologically distinct liver tumours were initiated by hydrodynamic transfection of oncogenic V-Akt Murine Thymoma Viral Oncogene Homolog 1 (AKT)/β-catenin or AKT/Notch expressing plasmids. To investigate the relationship of LTβR signalling and specific oncogenic pathways, LTβR antagonist (LTβR-Fc) or agonist (anti-LTβR) were administered post oncogene transfection. Initiated livers/tumours were investigated for changes in oncogene expression, tumour proliferation, progression, latency and pathology. Moreover, specific LTβR-mediated molecular events were investigated in human liver cancer cell lines and through transcriptional analyses of samples from patients with intrahepatic cholangiocarcinoma (ICC). Results AKT/β-catenin-transfected livers displayed increased expression of LTβ and LTβR, with antagonism of LTβR signalling reducing tumour progression and enhancing survival. Conversely, enforced LTβR-activation of AKT/β-catenin-initiated tumours induced robust increases in proliferation and progression of hepatic tumour phenotypes in an AKT-dependent manner. LTβR-activation also rapidly accelerated ICC progression initiated by AKT/Notch, but not Notch alone. Moreover, LTβR-accelerated development coincides with increases of Notch, Hes1, c-MYC, pAKT and β-catenin. We further demonstrate LTβR signalling in human liver cancer cell lines to be a regulator of Notch, pAKTser473 and β-catenin. Transcriptome analysis of samples from patients with ICC links increased LTβR network expression with poor patient survival, increased

  4. Messenger RNA (mRNA) nanoparticle tumour vaccination

    Science.gov (United States)

    Phua, Kyle K. L.; Nair, Smita K.; Leong, Kam W.

    2014-06-01

    Use of mRNA-based vaccines for tumour immunotherapy has gained increasing attention in recent years. A growing number of studies applying nanomedicine concepts to mRNA tumour vaccination show that the mRNA delivered in nanoparticle format can generate a more robust immune response. Advances in the past decade have deepened our understanding of gene delivery barriers, mRNA's biological stability and immunological properties, and support the notion for engineering innovations tailored towards a more efficient mRNA nanoparticle vaccine delivery system. In this review we will first examine the suitability of mRNA for engineering manipulations, followed by discussion of a model framework that highlights the barriers to a robust anti-tumour immunity mediated by mRNA encapsulated in nanoparticles. Finally, by consolidating existing literature on mRNA nanoparticle tumour vaccination within the context of this framework, we aim to identify bottlenecks that can be addressed by future nanoengineering research.

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

    DEFF Research Database (Denmark)

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

    2014-01-01

    fibroblasts. This screen led to the identification of miR-378a-5p and in addition several other miRNAs that have previously been shown to play a role in senescence. We show that ectopic expression of miR-378a-5p reduces the expression of several senescence markers, including p16INK4A and senescence......Oncogene-induced senescence (OIS) can occur in response to hyperactive oncogenic signals and is believed to be a fail-safe mechanism protecting against tumorigenesis. To identify new factors involved in OIS, we performed a screen for microRNAs that can overcome or inhibit OIS in human diploid......-associated β-galactosidase. Moreover, cells with ectopic expression of miR-378a-5p retain proliferative capacity even in the presence of an activated Braf oncogene. Finally, we identified several miR-378a-5p targets in diploid fibroblasts that might explain the mechanism by which the microRNA can delay OIS. We...

  6. Integrated genome-wide genotyping and gene expression profiling reveals BCL11B as a putative oncogene in acute myeloid leukemia with 14q32 aberrations.

    Science.gov (United States)

    Abbas, Saman; Sanders, Mathijs A; Zeilemaker, Annelieke; Geertsma-Kleinekoort, Wendy M C; Koenders, Jasper E; Kavelaars, Francois G; Abbas, Zabiollah G; Mahamoud, Souad; Chu, Isabel W T; Hoogenboezem, Remco; Peeters, Justine K; van Drunen, Ellen; van Galen, Janneke; Beverloo, H Berna; Löwenberg, Bob; Valk, Peter J M

    2014-05-01

    Acute myeloid leukemia is a neoplasm characterized by recurrent molecular aberrations traditionally demonstrated by cytogenetic analyses. We used high density genome-wide genotyping and gene expression profiling to reveal acquired cryptic abnormalities in acute myeloid leukemia. By genome-wide genotyping of 137 cases of primary acute myeloid leukemia, we disclosed a recurrent focal amplification on chromosome 14q32, which included the genes BCL11B, CCNK, C14orf177 and SETD3, in two cases. In the affected cases, the BCL11B gene showed consistently high mRNA expression, whereas the expression of the other genes was unperturbed. Fluorescence in situ hybridization on 40 cases of acute myeloid leukemia with high BCL11B mRNA expression [2.5-fold above median; 40 out of 530 cases (7.5%)] revealed 14q32 abnormalities in two additional cases. In the four BCL11B-rearranged cases the 14q32 locus was fused to different partner chromosomes. In fact, in two cases, we demonstrated that the focal 14q32 amplifications were integrated into transcriptionally active loci. The translocations involving BCL11B result in increased expression of full-length BCL11B protein. The BCL11B-rearranged acute myeloid leukemias expressed both myeloid and T-cell markers. These biphenotypic acute leukemias all carried FLT3 internal tandem duplications, a characteristic marker of acute myeloid leukemia. BCL11B mRNA expression in acute myeloid leukemia appeared to be strongly associated with expression of other T-cell-specific genes. Myeloid 32D(GCSF-R) cells ectopically expressing Bcl11b showed decreased proliferation rate and less maturation. In conclusion, by an integrated approach involving high-throughput genome-wide genotyping and gene expression profiling we identified BCL11B as a candidate oncogene in acute myeloid leukemia.

  7. miR-223 regulates cell growth and targets proto-oncogenes in mycosis fungoides/cutaneous T-cell lymphoma.

    Science.gov (United States)

    McGirt, Laura Y; Adams, Clare M; Baerenwald, Devin A; Zwerner, Jeffrey P; Zic, John A; Eischen, Christine M

    2014-04-01

    The pathogenesis of the cutaneous T-cell lymphoma (CTCL), mycosis fungoides (MF), is unclear. MicroRNA (miRNA) are small noncoding RNAs that target mRNA leading to reduced mRNA translation. Recently, specific miRNA were shown to be altered in CTCL. We detected significantly reduced expression of miR-223 in early-stage MF skin, and further decreased levels of miR-223 in advanced-stage disease. CTCL peripheral blood mononuclear cells and cell lines also had reduced miR-223 as compared with controls. Elevated expression of miR-223 in these cell lines reduced cell growth and clonogenic potential, whereas inhibition of miR-223 increased cell numbers. Investigations into putative miR-223 targets with oncogenic function, including E2F1 and MEF2C, and the predicted miR-223 target, TOX, revealed that all three were targeted by miR-223 in CTCL. E2F1, MEF2C, and TOX proteins were decreased with miR-223 overexpression, whereas miR-223 inhibition led to increased protein levels in CTCL. In addition, we showed that the 3'-UTR of TOX mRNA was a genuine target of miR-223. Therefore, reduced levels of miR-223 in MF/CTCL lead to increased expression of E2F1, MEF2C, and TOX, which likely contributes to the development and/or progression of CTCL. Thus, miR-223 and its targets may be useful for the development of new therapeutics for MF/CTCL.

  8. Recent innovations in mRNA vaccines.

    Science.gov (United States)

    Ulmer, Jeffrey B; Geall, Andrew J

    2016-08-01

    Nucleic acid-based vaccines are being developed as a means to combine the positive attributes of both live-attenuated and subunit vaccines. Viral vectors and plasmid DNA vaccines have been extensively evaluated in human clinical trials and have been shown to be safe and immunogenic, although none have yet been licensed for human use. Recently, mRNA based vaccines have emerged as an alternative approach. They promise the flexibility of plasmid DNA vaccines, without the need for electroporation, but with enhanced immunogenicity and safety. In addition, they avoid the limitations of anti-vector immunity seen with viral vectors, and can be dosed repeatedly. This review highlights the key papers published over the past few years and summarizes prospects for the near future.

  9. Alternative polyadenylation of mRNA precursors

    Science.gov (United States)

    Tian, Bin; Manley, James L.

    2017-01-01

    Alternative polyadenylation (APA) is an RNA-processing mechanism that generates distinct 3′ termini on mRNAs and other RNA polymerase II transcripts. It is widespread across all eukaryotic species and is recognized as a major mechanism of gene regulation. APA exhibits tissue specificity and is important for cell proliferation and differentiation. In this Review, we discuss the roles of APA in diverse cellular processes, including mRNA metabolism, protein diversification and protein localization, and more generally in gene regulation. We also discuss the molecular mechanisms underlying APA, such as variation in the concentration of core processing factors and RNA-binding proteins, as well as transcription-based regulation. PMID:27677860

  10. Aggressive transformation of juvenile myelomonocytic leukemia associated with duplication of oncogenic KRAS due to acquired uniparental disomy.

    Science.gov (United States)

    Kato, Motohiro; Yasui, Naoko; Seki, Masafumi; Kishimoto, Hiroshi; Sato-Otsubo, Aiko; Hasegawa, Daisuke; Kiyokawa, Nobutaka; Hanada, Ryoji; Ogawa, Seishi; Manabe, Atsushi; Takita, Junko; Koh, Katsuyoshi

    2013-06-01

    A small fraction of cases of juvenile myelomonocytic leukemia (JMML) develop massive disease activation. Through genomic analysis of JMML, which developed in an individual with mosaicism for oncogenic KRAS mutation with rapid progression, we identified acquired uniparental disomy at 12p. We demonstrated that duplication of oncogenic KRAS is associated with rapid JMML progression.

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

    NARCIS (Netherlands)

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

    1983-01-01

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

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

    NARCIS (Netherlands)

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

    1998-01-01

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

  13. Detection and Elimination of Oncogenic Signaling Networks in Premalignant and Malignant Cells with Magnetic Resonance Imaging

    Science.gov (United States)

    2015-10-01

    work on Projects 2 and 3, and minimized efforts of Drs. Neil Spector and Chris Lascola . We have also added more professional support for project...95-100 melting point NMR data LCMS data comment NMR datafile on Entire sample given to Chris Lascola LCMS datafile yes 162. HS-100143-01 N N N N S N

  14. Detection and Elimination of Oncogenic Signalling Networks in Premalignant and Malignant Cells with Magnetic Resonance Imaging

    Science.gov (United States)

    2015-10-01

    work on Projects 2 and 3, and minimized efforts of Drs. Neil Spector and Chris Lascola . We have also added more professional support for project...95-100 melting point NMR data LCMS data comment NMR datafile on Entire sample given to Chris Lascola LCMS datafile yes 162. HS-100143-01 N N N N S N

  15. Immunology in the clinic review series; focus on cancer: multiple roles for the immune system in oncogene addiction.

    Science.gov (United States)

    Bachireddy, P; Rakhra, K; Felsher, D W

    2012-02-01

    Despite complex genomic and epigenetic abnormalities, many cancers are irrevocably dependent on an initiating oncogenic lesion whose restoration to a normal physiological activation can elicit a dramatic and sudden reversal of their neoplastic properties. This phenomenon of the reversal of tumorigenesis has been described as oncogene addiction. Oncogene addiction had been thought to occur largely through tumour cell-autonomous mechanisms such as proliferative arrest, apoptosis, differentiation and cellular senescence. However, the immune system plays an integral role in almost every aspect of tumorigenesis, including tumour initiation, prevention and progression as well as the response to therapeutics. Here we highlight more recent evidence suggesting that oncogene addiction may be integrally dependent upon host immune-mediated mechanisms, including specific immune effectors and cytokines that regulate tumour cell senescence and tumour-associated angiogenesis. Hence, the host immune system is essential to oncogene addiction.

  16. Human gene control by vital oncogenes: revisiting a theoretical model and its implications for targeted cancer therapy.

    Science.gov (United States)

    Willis, Rudolph E

    2012-01-01

    An important assumption of our current understanding of the mechanisms of carcinogenesis has been the belief that clarification of the cancer process would inevitably reveal some of the crucial mechanisms of normal human gene regulation. Since the momentous work of Bishop and Varmus, both the molecular and the biochemical processes underlying the events in the development of cancer have become increasingly clear. The identification of cellular signaling pathways and the role of protein kinases in the events leading to gene activation have been critical to our understanding not only of normal cellular gene control mechanisms, but also have clarified some of the important molecular and biochemical events occurring within a cancer cell. We now know that oncogenes are dysfunctional proto-oncogenes and that dysfunctional tumor suppressor genes contribute to the cancer process. Furthermore, Weinstein and others have hypothesized the phenomenon of oncogene addiction as a distinct characteristic of the malignant cell. It can be assumed that cancer cells, indeed, become dependent on such vital oncogenes. The products of these vital oncogenes, such as c-myc, may well be the Achilles heel by which targeted molecular therapy may lead to truly personalized cancer therapy. The remaining problem is the need to introduce relevant molecular diagnostic tests such as genome microarray analysis and proteomic methods, especially protein kinase identification arrays, for each individual patient. Genome wide association studies on cancers with gene analysis of single nucleotide and other mutations in functional proto-oncogenes will, hopefully, identify dysfunctional proto-oncogenes and allow the development of more specific targeted drugs directed against the protein products of these vital oncogenes. In 1984 Willis proposed a molecular and biochemical model for eukaryotic gene regulation suggesting how proto-oncogenes might function within the normal cell. That model predicted the

  17. Oncogenic GNAQ mutations are not correlated with disease-free survival in uveal melanoma

    NARCIS (Netherlands)

    Bauer, J.; Kilic, E.; Vaarwater, J.; Bastian, B. C.; Garbe, C.; de Klein, A.

    2009-01-01

    BACKGROUND: Recently, oncogenic G protein alpha subunit q (GNAQ) mutations have been described in about 50% of uveal melanomas and in the blue nevi of the skin. METHODS: GNAQ exon 5 was amplified from 75 ciliary body and choroidal melanoma DNAs and sequenced directly. GNAQ mutation status was correl

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

    Directory of Open Access Journals (Sweden)

    Mary Ann S. Crissey

    2008-01-01

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

  19. N-Linked oligosaccharide changes with oncogenic transformation require sialylation of multiantennae

    NARCIS (Netherlands)

    Vliegenthart, J.F.G.; Santer, U.V.; DeSantis, R.; Hård, K.; Kuik, J.A. van; Won, B.; Glick, M.C.

    1989-01-01

    Glycopeptides derived from NIH 3T3 fibroblasts and these cells transformed by transfection with human DNA containing oncogene H-ras were analyzed by 500-MHz 1H-NMR spectroscopy and binding to immobilized lectins. The cells were metabolically labeled with D-[3H]glucosamine or L-[3H]fucose and the gly

  20. Escape from premature senescence is not sufficient for oncogenic transformation by Ras

    NARCIS (Netherlands)

    Peeper, D.S.; Dannenberg, J.-H.; Douma, S.; Riele, H. te; Bernards, R.A.

    2001-01-01

    Resistance of primary cells to transformation by oncogenic Ras has been attributed to the induction of replicative growth arrest1, 2, 3. This irreversible 'fail-safe mechanism' resembles senescence and requires induction by Ras of p19ARF and p53 (refs 3−5). Mutation of either p19ARF or p53 alleviate

  1. Clinical relevance of the K-ras oncogene in colorectal cancer: Experience in a Mexican population

    Directory of Open Access Journals (Sweden)

    F. Cabrera-Mendoza

    2014-07-01

    Conclusions: No relation was found between the K-ras oncogene mutation and reduced survival, in contrast to what has been established in the international medical literature. Further studies that include both a larger number of patients and those receiving monoclonal treatment, need to be conducted. There were only 5 patients in the present study that received cetuximab, resulting in a misleading analysis.

  2. Oncogenic events associated with endometrial and ovarian cancers are rare in endometriosis

    DEFF Research Database (Denmark)

    Vestergaard, Anna Lindeløv; Thorup, Katrine; Knudsen, Ulla Breth

    2011-01-01

    using methylation-specific melting curve analysis (MS-MCA), and 9 genes (BRAF, HRAS, NRAS, CTNNB1, CDK4, FGFR3, PIK3CA, TP53 and PTEN) were analyzed for mutations using denaturing gradient gel electrophoresis (DGGE) and direct sequencing. An oncogenic mutation in KRAS (c. 34G>T; p.G12C) was detected...

  3. Microarray-Based oncogenic pathway profiling in advanced serous papillary ovarian carcinoma

    NARCIS (Netherlands)

    X.B. Trinh; W.A.A. Tjalma (Wiebren); L. Dirix (Luc); P.B. Vermeulen; D. Peeters (Dieter); D. Bachvarov (Dimcho); M. Plante (Marie); P.M.J.J. Berns (Els); J. Helleman (Jozien); S.J. van Laere; P.A. van Dam

    2011-01-01

    textabstractIntroduction: The identification of specific targets for treatment of ovarian cancer patients remains a challenge. The objective of this study is the analysis of oncogenic pathways in ovarian cancer and their relation with clinical outcome. Methodology: A meta-analysis of 6 gene expressi

  4. Gene expression of oncogenes, antimicrobial peptides, and cytokines in the development of oral leukoplakia.

    NARCIS (Netherlands)

    Wenghoefer, M.; Pantelis, A.; Najafi, T.; Deschner, J.; Allam, J.P.; Novak, N.; Reich, R.; Martini, M.; Berge, S.J.; Fischer, H.P.; Jepsen, S.; Winter, J.

    2010-01-01

    OBJECTIVE: The aim of this study was to investigate the expression pattern of oncogenes, antimicrobial peptides, and genes involved in inflammation in leukoplakia of the oral cavity compared with healthy gingiva. STUDY DESIGN: Biopsies of healthy gingiva (n=20) and leukoplakia (n=20), were obtained

  5. K-ras oncogene mutations in sporadic colorectal cancer in The Netherlands Cohort Study

    NARCIS (Netherlands)

    Brink, M.; Goeij, A.F.P.M. de; Weijenberg, M.P.; Roemen, G.M.J.M.; Lentjes, M.H.F.M.; Pachen, M.M.M.; Smits, K.M.; Bruïne, A.P. de; Goldbohm, R.A.; Brandt, P.A. van den

    2003-01-01

    Activation of K-ras oncogene has been implicated in colorectal carcinogenesis, being mutated in 30-60% of the adenocarcinomas. In this study, 737 incident colorectal cancer (CRC) patients, originating from 120 852 men and women (55-69 years at baseline) participating in the Netherlands Cohort Study

  6. For better or for worse : the role of Pim oncogenes in tumorigenesis

    NARCIS (Netherlands)

    Nawijn, Martijn C.; Alendar, Andrej; Berns, Anton

    2011-01-01

    Pim oncogenes are overexpressed in a wide range of tumours from a haematological and epithelial origin. Pim genes encode serine/threonine kinases that have been shown to counteract the increased sensitivity to apoptosis induction that is associated with MYC-driven tumorigenesis. Recently, considerab

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

    NARCIS (Netherlands)

    Graaf, Ymke Grete Leontien de

    2008-01-01

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

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

    NARCIS (Netherlands)

    Graaf, Ymke Grete Leontien de

    2008-01-01

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

  9. Gene expression of oncogenes, antimicrobial peptides, and cytokines in the development of oral leukoplakia.

    NARCIS (Netherlands)

    Wenghoefer, M.; Pantelis, A.; Najafi, T.; Deschner, J.; Allam, J.P.; Novak, N.; Reich, R.; Martini, M.; Berge, S.J.; Fischer, H.P.; Jepsen, S.; Winter, J.

    2010-01-01

    OBJECTIVE: The aim of this study was to investigate the expression pattern of oncogenes, antimicrobial peptides, and genes involved in inflammation in leukoplakia of the oral cavity compared with healthy gingiva. STUDY DESIGN: Biopsies of healthy gingiva (n=20) and leukoplakia (n=20), were obtained

  10. Targeted expression of oncogenic K-ras in intestinal epithelium causes spontaneous tumorigenesis in mice

    NARCIS (Netherlands)

    Janssen, KP; El Marjou, F; Pinto, D; Sastre, X; Rouillard, D; Fouquet, C; Soussi, T; Louvard, D; Robine, S

    2002-01-01

    Background & Aims: Ras oncoproteins are mutated in about 50% of human colorectal cancers, but their precise role in tumor initiation or progression is still unclear. Methods: This study presents transgenic mice that express K-ras(V12G), the most frequent oncogenic mutation in human tumors, under con

  11. Correlation between oncogenic mutations and parameter sensitivity of the apoptosis pathway model.

    Directory of Open Access Journals (Sweden)

    Jia Chen

    2014-01-01

    Full Text Available One of the major breakthroughs in oncogenesis research in recent years is the discovery that, in most patients, oncogenic mutations are concentrated in a few core biological functional pathways. This discovery indicates that oncogenic mechanisms are highly related to the dynamics of biologic regulatory networks, which govern the behaviour of functional pathways. Here, we propose that oncogenic mutations found in different biological functional pathways are closely related to parameter sensitivity of the corresponding networks. To test this hypothesis, we focus on the DNA damage-induced apoptotic pathway--the most important safeguard against oncogenesis. We first built the regulatory network that governs the apoptosis pathway, and then translated the network into dynamics equations. Using sensitivity analysis of the network parameters and comparing the results with cancer gene mutation spectra, we found that parameters that significantly affect the bifurcation point correspond to high-frequency oncogenic mutations. This result shows that the position of the bifurcation point is a better measure of the functionality of a biological network than gene expression levels of certain key proteins. It further demonstrates the suitability of applying systems-level analysis to biological networks as opposed to studying genes or proteins in isolation.

  12. Complex Oncogenic Translocations with Gene Amplification are Initiated by Specific DNA Breaks in Lymphocytes

    OpenAIRE

    2009-01-01

    Chromosomal instability is a hallmark of many tumor types. Complex chromosomal rearrangements with associated gene amplification, known as complicons, characterize many hematologic and solid cancers. While chromosomal aberrations, including complicons, are useful diagnostic and prognostic cancer markers, their molecular origins are not known. Although accumulating evidence has implicated DNA double strand break repair in suppression of oncogenic genome instability, the genomic elements requir...

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

    NARCIS (Netherlands)

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

    2014-01-01

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

  14. Role of STAT3 in in vitro transformation triggered by TRK oncogenes.

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    Claudia Miranda

    Full Text Available TRK oncoproteins are chimeric versions of the NTRK1/NGF receptor and display constitutive tyrosine kinase activity leading to transformation of NIH3T3 cells and neuronal differentiation of PC12 cells. Signal Transducer and Activator of Transcription (STAT 3 is activated in response to cytokines and growth factors and it has been recently identified as a novel signal transducer for TrkA, mediating the functions of NGF in nervous system. In this paper we have investigated STAT3 involvement in signalling induced by TRK oncogenes. We showed that TRK oncogenes trigger STAT3 phosphorylation both on Y705 and S727 residues and STAT3 transcriptional activity. MAPK pathway was involved in the induction of STAT3 phosphorylation. Interestingly, we have shown reduced STAT3 protein level in NIH3T3 transformed foci expressing TRK oncogenes. Overall, we have unveiled a dual role for STAT3 in TRK oncogenes-induced NIH3T3 transformation: i decreased STAT3 protein levels, driven by TRK oncoproteins activity, are associated to morphological transformation; ii residual STAT3 transcriptional activity is required for cell growth.

  15. The contribution of tumor and host tissue factor expression to oncogene-driven gliomagenesis.

    Science.gov (United States)

    Magnus, Nathalie; Meehan, Brian; Garnier, Delphine; Hashemi, Maryam; Montermini, Laura; Lee, Tae Hoon; Milsom, Chloe; Pawlinski, Rafal; Ohlfest, John; Anderson, Mark; Mackman, Nigel; Rak, Janusz

    2014-11-14

    Glioblastoma multiforme (GBM) is an aggressive form of glial brain tumors, associated with angiogenesis, thrombosis, and upregulation of tissue factor (TF), the key cellular trigger of coagulation and signaling. Since TF is upregulated by oncogenic mutations occurring in different subsets of human brain tumors we investigated whether TF contributes to tumourigenesis driven by oncogenic activation of EGFR (EGFRvIII) and RAS pathways in the brain. Here we show that TF expression correlates with poor prognosis in glioma, but not in GBM. In situ, the TF protein expression is heterogeneously expressed in adult and pediatric gliomas. GBM cells harboring EGFRvIII (U373vIII) grow aggressively as xenografts in SCID mice and their progression is delayed by administration of monoclonal antibodies blocking coagulant (CNTO 859) and signaling (10H10) effects of TF in vivo. Mice in which TF gene is disrupted in the neuroectodermal lineage exhibit delayed progression of spontaneous brain tumors driven by oncogenic N-ras and SV40 large T antigen (SV40LT) expressed under the control of sleeping beauty transposase. Reduced host TF levels in low-TF/SCID hypomorphic mice mitigated growth of glioma subcutaneously but not in the brain. Thus, we suggest that tumor-associated TF may serve as therapeutic target in the context of oncogene-driven disease progression in a subset of glioma.

  16. Netrin-1 exerts oncogenic activities through enhancing Yes-associated protein stability.

    Science.gov (United States)

    Qi, Qi; Li, Dean Y; Luo, Hongbo R; Guan, Kun-Liang; Ye, Keqiang

    2015-06-09

    Yes-associated protein (YAP), a transcription coactivator, is the major downstream effector of the Hippo pathway, which plays a critical role in organ size control and cancer development. However, how YAP is regulated by extracellular stimuli in tumorigenesis remains incompletely understood. Netrin-1, a laminin-related secreted protein, displays proto-oncogenic activity in cancers. Nonetheless, the downstream signaling mediating its oncogenic effects is not well defined. Here we show that netrin-1 via its transmembrane receptors, deleted in colorectal cancer and uncoordinated-5 homolog, up-regulates YAP expression, escalating YAP levels in the nucleus and promoting cancer cell proliferation and migration. Inactivating netrin-1, deleted in colorectal cancer, or uncoordinated-5 homolog B (UNC5B) decreases YAP protein levels, abrogating cancer cell progression by netrin-1, whereas knockdown of mammalian STE20-like protein kinase 1/2 (MST1/2) or large tumor suppressor kinase 1/2 (Lats1/2), two sets of upstream core kinases of the Hippo pathway, has no effect in blocking netrin-1-induced up-regulation of YAP. Netrin-1 stimulates phosphatase 1A to dephosphorylate YAP, which leads to decreased ubiquitination and degradation, enhancing YAP accumulation and signaling. Hence, our findings support that netrin-1 exerts oncogenic activity through YAP signaling, providing a mechanism coupling extracellular signals to the nuclear YAP oncogene.

  17. Src-like-adaptor protein (SLAP) differentially regulates normal and oncogenic c-Kit signaling.

    Science.gov (United States)

    Kazi, Julhash U; Agarwal, Shruti; Sun, Jianmin; Bracco, Enrico; Rönnstrand, Lars

    2014-02-01

    The Src-like-adaptor protein (SLAP) is an adaptor protein sharing considerable structural homology with Src. SLAP is expressed in a variety of cells and regulates receptor tyrosine kinase signaling by direct association. In this report, we show that SLAP associates with both wild-type and oncogenic c-Kit (c-Kit-D816V). The association involves the SLAP SH2 domain and receptor phosphotyrosine residues different from those mediating Src interaction. Association of SLAP triggers c-Kit ubiquitylation which, in turn, is followed by receptor degradation. Although SLAP depletion potentiates c-Kit downstream signaling by stabilizing the receptor, it remains non-functional in c-Kit-D816V signaling. Ligand-stimulated c-Kit or c-Kit-D816V did not alter membrane localization of SLAP. Interestingly oncogenic c-Kit-D816V, but not wild-type c-Kit, phosphorylates SLAP on residues Y120, Y258 and Y273. Physical interaction between c-Kit-D816V and SLAP is mandatory for the phosphorylation to take place. Although tyrosine-phosphorylated SLAP does not affect c-Kit-D816V signaling, mutation of these tyrosine sites to phenylalanine can restore SLAP activity. Taken together the data demonstrate that SLAP negatively regulates wild-type c-Kit signaling, but not its oncogenic counterpart, indicating a possible mechanism by which the oncogenic c-Kit bypasses the normal cellular negative feedback control.

  18. Calpain Activity Is Generally Elevated during Transformation but Has Oncogene-Specific Biological Functions

    Directory of Open Access Journals (Sweden)

    N.O. Carragher

    2004-01-01

    Full Text Available Several oncogene and tumor-suppressor gene products are known substrates for the calpain family of cysteine proteases, and calpain is required for transformation by v-src and tumor invasion. Thus, we have now addressed whether calpain is generally associated with transformation and how calpain contributes to oncogene function. Our results demonstrate that calpain activity is enhanced upon transformation induced by the v-Src, v-Jun, v-Myc, k-Ras, and v-Fos oncoproteins. Furthermore, elevated calpain activity commonly promotes focal adhesion remodelling, disruption of actin cytoskeleton, morphological transformation, and cell migration, although proteolysis of target substrates (such as focal adhesion kinase, talin, and spectrin is differently specified by individual oncoproteins. Interestingly, v-Fos differs from other common oncoproteins in not requiring calpain activity for actin/adhesion remodelling or migration of v-Fos transformed cells. However, anchorage-independent growth of all transformed cells is sensitive to calpain inhibition. In addition, elevated calpain activity contributes to oncogene-induced apoptosis associated with transformation by v-Myc. Taken together, these studies demonstrate that calpain activity is necessary for full cellular transformation induced by common oncoproteins, but has distinct roles in oncogenic events induced by individual transforming proteins. Thus, targeting calpain activity may represent a useful general strategy for interfering with activated protooncogenes in cancer cells.

  19. Analyses of domains and domain fusions in human proto-oncogenes

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    Wan Ping

    2009-03-01

    Full Text Available Abstract Background Understanding the constituent domains of oncogenes, their origins and their fusions may shed new light about the initiation and the development of cancers. Results We have developed a computational pipeline for identification of functional domains of human genes, prediction of the origins of these domains and their major fusion events during evolution through integration of existing and new tools of our own. An application of the pipeline to 124 well-characterized human oncogenes has led to the identification of a collection of domains and domain pairs that occur substantially more frequently in oncogenes than in human genes on average. Most of these enriched domains and domain pairs are related to tyrosine kinase activities. In addition, our analyses indicate that a substantial portion of the domain-fusion events of oncogenes took place in metazoans during evolution. Conclusion We expect that the computational pipeline for domain identification, domain origin and domain fusion prediction will prove to be useful for studying other groups of genes.

  20. Repeat-element driven activation of proto-oncogenes in human malignancies.

    Science.gov (United States)

    Lamprecht, Björn; Bonifer, Constanze; Mathas, Stephan

    2010-11-01

    Recent data demonstrated that the aberrant activity of endogenous repetitive elements of the DNA in humans can drive the expression of proto-oncogenes. This article summarizes these results and gives an outlook on the impact of these findings on the pathogenesis and therapy of human cancer.

  1. Oncogenic Splicing Factor SRSF1 Is a Critical Transcriptional Target of MYC

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    Shipra Das

    2012-02-01

    Full Text Available The SR protein splicing factor SRSF1 is a potent proto-oncogene that is frequently upregulated in cancer. Here, we show that SRSF1 is a direct target of the transcription factor oncoprotein MYC. These two oncogenes are significantly coexpressed in lung carcinomas, and MYC knockdown downregulates SRSF1 expression in lung-cancer cell lines. MYC directly activates transcription of SRSF1 through two noncanonical E-boxes in its promoter. The resulting increase in SRSF1 protein is sufficient to modulate alternative splicing of a subset of transcripts. In particular, MYC induction leads to SRSF1-mediated alternative splicing of the signaling kinase MKNK2 and the transcription factor TEAD1. SRSF1 knockdown reduces MYC's oncogenic activity, decreasing proliferation and anchorage-independent growth. These results suggest a mechanism for SRSF1 upregulation in tumors with elevated MYC and identify SRSF1 as a critical MYC target that contributes to its oncogenic potential by enabling MYC to regulate the expression of specific protein isoforms through alternative splicing.

  2. Human Epidermal Growth Factor Receptor-3 mRNA Expression as a Prognostic Marker for Invasive Duct Carcinoma not Otherwise Specified

    Science.gov (United States)

    Hammoda, Ghada Ezat; El-Hefnawy, Sally Mohammed; Abdallah, Rania Abdallah

    2017-01-01

    Introduction Breast cancer is the most common cancer in women and the Erythroblastosis Oncogene B(ErbB) receptor family holds crucial role in its pathogenesis. Human Epidermal Growth Factor Receptor 3 (HER-3) gene over expression in breast tissue has been associated with aggressive clinical behaviour and bad prognosis. Aim To evaluate HER-3 mRNA expression level as a prognostic marker for breast cancer and to correlate its level with other established prognostic parameters. Materials and Methods This study was carried out on specimens of 100 cases that were divided into 40 patients presented with fibroadenoma and 60 patients presented with Invasive Ductal Carcinoma (IDC) not otherwise specified and underwent modified radical mastectomy. All specimens were investigated for HER-2/neu, ER and PR expression by Immunohistochemistry (IHC) and quantitative assay of HER-3 mRNA expression using real time PCR technique. Results There was a significant high HER3 mRNA level in carcinoma cases compared to fibroadenoma. In malignant cases, HER3 mRNA level was significantly associated with advanced T stage, advanced N stage, number of positive lymph nodes, large tumour size and cases associated with an adjacent in situ component. Moreover, HER-3 mRNA level was of highest values in Her-2/neu positive group followed by triple negative cases with the lowest level in luminal group (p<0.05). Conclusion HER-3 gene is upregulated in IDC especially those carrying poor prognostic features. HER-3 mRNA level may identify a subset of patients with a poor prognosis, and who could undergo further evaluation for the efficacy of HER3 targeted anticancer therapy. PMID:28384967

  3. Stathmin 1 is a potential novel oncogene in melanoma.

    Science.gov (United States)

    Chen, J; Abi-Daoud, M; Wang, A; Yang, X; Zhang, X; Feilotter, H E; Tron, V A

    2013-03-07

    In previous studies, we demonstrated that miR-193b expression is reduced in melanoma relative to benign nevi, and also that miR-193b represses cyclin D1 and Mcl-1 expression. We suggested that stathmin 1 (STMN1) might be a target of miR-193b. STMN1 normally regulates microtubule dynamics either by sequestering free tubulin heterodimers or by promoting microtubule catastrophe. Increased expression of STMN1 has been observed in a variety of human malignancies, but its association with melanoma is unknown. We now report that STMN1 is upregulated during the progression of melanoma relative to benign nevi, and that STMN1 is directly regulated by miR-193b. Using an experimental cell culture approach, overexpression of miR-193b using synthetic microRNAs repressed STMN1 expression, whereas inhibition of miR-193b with anti-miR oligos increased STMN1 expression in melanoma cells. The use of a luciferase reporter assay confirmed that miR-193b directly regulates STMN1 by targeting the 3'-untranslated region of STMN1 mRNA. We further demonstrated that STMN1 is overexpressed in malignant melanoma compared with nevi in two independent melanoma cohorts, and that its level is inversely correlated with miR-193b expression. However, STMN1 expression was not significantly associated with patient survival, Breslow depth, mitotic count or patient age. STMN1 knockdown by small-interfering RNA in melanoma cells drastically repressed cell proliferation and migration potential, whereas ectopic expression of STMN1 using lentivirus increased cell proliferation and migration rates. Subsequent gene expression analysis indicated that interconnected cytoskeletal networks are directly affected following STMN1 knockdown. In addition, we identified deregulated genes associated with proliferation and migration, and revealed that p21(Cip1/Waf1) and p27(Kip) could be downstream effectors of STMN1 signaling. Taken together, our study suggests that downregulation of miR-193b may contribute to increased

  4. Oncogenic signaling by Kit tyrosine kinase occurs selectively on the Golgi apparatus in gastrointestinal stromal tumors.

    Science.gov (United States)

    Obata, Y; Horikawa, K; Takahashi, T; Akieda, Y; Tsujimoto, M; Fletcher, J A; Esumi, H; Nishida, T; Abe, R

    2017-02-13

    Gastrointestinal stromal tumors (GISTs) are caused by gain-of-function mutations in the Kit receptor tyrosine kinase. Most primary GIST patients respond to the Kit inhibitor imatinib, but this drug often becomes ineffective because of secondary mutations in the Kit kinase domain. The characteristic intracellular accumulation of imatinib-sensitive and -resistant Kit protein is well documented, but its relationship to oncogenic signaling remains unknown. Here, we show that in cancer tissue from primary GIST patients as well as in cell lines, mutant Kit accumulates on the Golgi apparatus, whereas normal Kit localizes to the plasma membrane (PM). In imatinib-resistant GIST with a secondary Kit mutation, Kit localizes predominantly on the Golgi apparatus. Both imatinib-sensitive and imatinib-resistant Kit (Kit(mut)) become fully auto-phosphorylated only on the Golgi and only if in a complex-glycosylated form. Kit(mut) accumulates on the Golgi during the early secretory pathway, but not after endocytosis. The aberrant kinase activity of Kit(mut) prevents its export from the Golgi to the PM. Furthermore, Kit(mut) on the Golgi signals and activates the phosphatidylinositol 3-kinase-Akt (PI3K-Akt) pathway, signal transducer and activator of transcription 5 (STAT5), and the Mek-Erk pathway. Blocking the biosynthetic transport of Kit(mut) to the Golgi from the endoplasmic reticulum inhibits oncogenic signaling. PM localization of Kit(mut) is not required for its signaling. Activation of Src-family tyrosine kinases on the Golgi is essential for oncogenic Kit signaling. These results suggest that the Golgi apparatus serves as a platform for oncogenic Kit signaling. Our study demonstrates that Kit(mut)'s pathogenicity is related to its mis-localization, and may offer a new strategy for treating imatinib-resistant GISTs.Oncogene advance online publication, 13 February 2017; doi:10.1038/onc.2016.519.

  5. Analysis of multiple sarcoma expression datasets: implications for classification, oncogenic pathway activation and chemotherapy resistance.

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    Panagiotis A Konstantinopoulos

    Full Text Available BACKGROUND: Diagnosis of soft tissue sarcomas (STS is challenging. Many remain unclassified (not-otherwise-specified, NOS or grouped in controversial categories such as malignant fibrous histiocytoma (MFH, with unclear therapeutic value. We analyzed several independent microarray datasets, to identify a predictor, use it to classify unclassifiable sarcomas, and assess oncogenic pathway activation and chemotherapy response. METHODOLOGY/PRINCIPAL FINDINGS: We analyzed 5 independent datasets (325 tumor arrays. We developed and validated a predictor, which was used to reclassify MFH and NOS sarcomas. The molecular "match" between MFH and their predicted subtypes was assessed using genome-wide hierarchical clustering and Subclass-Mapping. Findings were validated in 15 paraffin samples profiled on the DASL platform. Bayesian models of oncogenic pathway activation and chemotherapy response were applied to individual STS samples. A 170-gene predictor was developed and independently validated (80-85% accuracy in all datasets. Most MFH and NOS tumors were reclassified as leiomyosarcomas, liposarcomas and fibrosarcomas. "Molecular match" between MFH and their predicted STS subtypes was confirmed both within and across datasets. This classification revealed previously unrecognized tissue differentiation lines (adipocyte, fibroblastic, smooth-muscle and was reproduced in paraffin specimens. Different sarcoma subtypes demonstrated distinct oncogenic pathway activation patterns, and reclassified MFH tumors shared oncogenic pathway activation patterns with their predicted subtypes. These patterns were associated with predicted resistance to chemotherapeutic agents commonly used in sarcomas. CONCLUSIONS/SIGNIFICANCE: STS profiling can aid in diagnosis through a predictor tracking distinct tissue differentiation in unclassified tumors, and in therapeutic management via oncogenic pathway activation and chemotherapy response assessment.

  6. Identifying mRNA targets of microRNA dysregulated in cancer: with application to clear cell Renal Cell Carcinoma

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    Liou Louis S

    2010-04-01

    Full Text Available Abstract Background MicroRNA regulate mRNA levels in a tissue specific way, either by inducing degradation of the transcript or by inhibiting translation or transcription. Putative mRNA targets of microRNA identified from seed sequence matches are available in many databases. However, such matches have a high false positive rate and cannot identify tissue specificity of regulation. Results We describe a simple method to identify direct mRNA targets of microRNA dysregulated in cancers from expression level measurements in patient matched tumor/normal samples. The word "direct" is used here in a strict sense to: a represent mRNA which have an exact seed sequence match to the microRNA in their 3'UTR, b the seed sequence match is strictly conserved across mouse, human, rat and dog genomes, c the mRNA and microRNA expression levels can distinguish tumor from normal with high significance and d the microRNA/mRNA expression levels are strongly and significantly anti-correlated in tumor and/or normal samples. We apply and validate the method using clear cell Renal Cell Carcinoma (ccRCC and matched normal kidney samples, limiting our analysis to mRNA targets which undergo degradation of the mRNA transcript because of a perfect seed sequence match. Dysregulated microRNA and mRNA are first identified by comparing their expression levels in tumor vs normal samples. Putative dysregulated microRNA/mRNA pairs are identified from these using seed sequence matches, requiring that the seed sequence be conserved in human/dog/rat/mouse genomes. These are further pruned by requiring a strong anti-correlation signature in tumor and/or normal samples. The method revealed many new regulations in ccRCC. For instance, loss of miR-149, miR-200c and mir-141 causes gain of function of oncogenes (KCNMA1, LOX, VEGFA and SEMA6A respectively and increased levels of miR-142-3p, miR-185, mir-34a, miR-224, miR-21 cause loss of function of tumor suppressors LRRC2, PTPN13, SFRP1

  7. Abundance of IFN-alpha and IFN-gamma mRNA in blood of resistant and susceptible chickens infected with Marek's disease virus (MDV) or vaccinated with turkey herpesvirus; and MDV inhibition of subsequent induction of IFN gene transcription.

    Science.gov (United States)

    Quéré, P; Rivas, C; Ester, K; Novak, R; Ragland, W L

    2005-03-01

    The effects of the very virulent RB-1B strain of Marek's disease virus (MDV) and turkey herpesvirus (HVT), a vaccinal strain, on abundance of IFN mRNA in the blood were investigated. MDV and HVT infection did not change the circulating level of IFN-gamma mRNA 1 and 7 days p.i., but they increased IFN-alpha mRNA levels slightly in genetically susceptible (to tumour development) B(13)/B(13) chickens. The total number of circulating leukocytes was unchanged and increase in message was accompanied by an increase in circulating CD8alpha(+) and MHC Class II(+) cells. On the contrary, both viruses slightly increased IFN-gamma transcripts and decreased IFN-alpha transcripts in genetically resistant B(21)/B(21) chickens. Further, oncogenic MDV was able to block the response to inactivated Newcastle disease virus, a potent inducer of IFN, in both chicken lines. The inhibiting effect on transcription was present for both IFN at days 1 and 7 p.i. in susceptible B(13)/B(13) chickens, but only at day 7 p.i. in resistant B(21)/B(21) chickens. By contrast, non-oncogenic HVT did not interfere with induction of either message at one day p.i. and MDV had a more suppressive effect than HVT on IFN gene transcription 7 days p.i. in B(21)/B(21) chickens. Thus, the strong ability of MDV to block induction of IFN gene transcription detected in the blood as soon as one day after infection in susceptible chickens, as opposed to resistant chickens, not only causes immunosuppression but also may be related to the virus's oncogenicity.

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

    Science.gov (United States)

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

    2016-10-25

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

  9. Studies on SSTR2 mRNA expression and its correlation to steroid receptors in human benign and malignant breast lesions

    Institute of Scientific and Technical Information of China (English)

    ZENG Xizhi(曾希志); YAO Zhenxiang(姚榛祥)

    2002-01-01

    Objective:This sudy was designed to observe somatostatin receptor subtype 2 (SSTR2) Mrna expression, and investigate the correlations between SSTR2 Mrna expression and steroid receptors in benign and malignant lesions of the breast. Methods: A total of 23 breast carcinomas,16 mammary hyperplasia and 9 mammary adenofibroma samples were analysed. The SSTR2 Mrna expression was examined by in situ hybridization using multiphase oligoprobes.The ER and PR were detected by immunohistochemical staining. A computerized image analysis system was utilized to estimate the relative contents of SSTR2 Mrna. Results: The positive rates of expression (87.0%) and relative contents (0.47) of SSTR2 Mrna in breast cancer were higher than those in benign breast lesions(64%,0.26) respectively( P<0.05). SSTR2 Mrna expression was closely correlated with ER and PR in breast cancer( P<0. 05), A positive correlation between SSTR2 Mrna expression and ER was also found in benign breast lesions. Conclusions: SSTR2 Mrna expressed both in benign and in malignant breast lesions, but higher in malignant than in benign ones. There was a significant positive correlation of SSTR2 Mrna expression with ER or PR. The results suggest that conbined treatment with an antiestrogen and a somatostatin analogue for ER-positive breast cancer is feasible.

  10. Analysis of MDM2 and MDM4 single nucleotide polymorphisms, mRNA splicing and protein expression in retinoblastoma.

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    Justina McEvoy

    Full Text Available Retinoblastoma is a childhood cancer of the developing retina that begins in utero and is diagnosed in the first years of life. Biallelic RB1 gene inactivation is the initiating genetic lesion in retinoblastoma. The p53 gene is intact in human retinoblastoma but the pathway is believed to be suppressed by increased expression of MDM4 (MDMX and MDM2. Here we quantify the expression of MDM4 and MDM2 mRNA and protein in human fetal retinae, primary retinoblastomas, retinoblastoma cell lines and several independent orthotopic retinoblastoma xenografts. We found that MDM4 is the major p53 antagonist expressed in retinoblastoma and in the developing human retina. We also discovered that MDM4 protein steady state levels are much higher in retinoblastoma than in human fetal retinae. This increase would not have been predicted based on the mRNA levels. We explored several possible post-transcriptional mechanisms that may contribute to the elevated levels of MDM4 protein. A proportion of MDM4 transcripts are alternatively spliced to produce protein products that are reported to be more stable and oncogenic. We also discovered that a microRNA predicted to target MDM4 (miR191 was downregulated in retinoblastoma relative to human fetal retinae and a subset of samples had somatic mutations that eliminated the miR-191 binding site in the MDM4 mRNA. Taken together, these data suggest that post-transcriptional mechanisms may contribute to stabilization of the MDM4 protein in retinoblastoma.

  11. A novel MCF-10A line allowing conditional oncogene expression in 3D culture

    Directory of Open Access Journals (Sweden)

    Danke Christina

    2011-07-01

    Full Text Available Introduction Non-transformed mammary epithelial cell lines such as MCF-10A recapitulate epithelial morphogenesis in three-dimensional (3D tissue culture by forming acinar structures. They represent an important tool to characterize the biological properties of oncogenes and to model early carcinogenic events. So far, however, these approaches were restricted to cells with constitutive oncogene expression prior to the set-up of 3D cultures. Although very informative, this experimental setting has precluded the analysis of effects caused by sudden oncoprotein expression or withdrawal in established epithelial cultures. Here, we report the establishment and use of a stable MCF-10A cell line (MCF-10Atet fitted with a novel and improved doxycycline (dox-regulated expression system allowing the conditional expression of any transgene. Methods MCF-10Atet cells were generated by stable transfection with pWHE644, a vector expressing a second generation tetracycline-regulated transactivator and a novel transcriptional silencer. In order to test the properties of this new repressor/activator switch, MCF-10Atet cells were transfected with a second plasmid, pTET-HABRAF-IRES-GFP, which responds to dox treatment with the production of a bi-cistronic transcript encoding hemagglutinin-tagged B-Raf and green fluorescent protein (GFP. This improved conditional expression system was then characterized in detail in terms of its response to various dox concentrations and exposure times. The plasticity of the phenotype provoked by oncogenic B-RafV600E in MCF-10Atet cells was analyzed in 3D cultures by dox exposure and subsequent wash-out. Results MCF-10Atet cells represent a tightly controlled, conditional gene expression system. Using B-RafV600E as a model oncoprotein, we show that its sudden expression in established 3D cultures results in the loss of acinar organization, the induction of an invasive phenotype and hallmarks of epithelial-to-mesenchymal transition

  12. Oncogenic HPV among HIV infected female population in West Bengal, India

    Directory of Open Access Journals (Sweden)

    Sengupta Sharmila

    2011-03-01

    Full Text Available Abstract Background Prevalence of both cervical cancer and Human Immunodeficiency Virus (HIV infection are very high in India. Natural history of Human Papilloma Virus (HPV infection is known to be altered in HIV positive women and there is an increased possibility of persistence of HPV infections in this population. Therefore, this study was conducted to understand the epidemiology and circulating genotypes of oncogenic HPV among HIV positive and negative female population in West Bengal, India. Methods In this hospital-based cross-sectional study, 93 known HIV positive females attending a pre-ART registration clinic and 1106 HIV negative females attending a Reproductive and Child Health Care Clinic were subjected to study. Cervical cell samples collected from the study population were tested for the presence of HPV 16, 18 using specific primers. Roche PCR assay was used to detect other specific HPV genotypes in the cervical cells specimens of HIV positive cases only. Results Prevalence of HPV 16, 18 among HIV positive females (32.2%; n = 30 was higher than HIV negative females (9.1%; n = 101. About 53% (23/43 of cases with oncogenic HPV were infected with genotypes other than 16, 18 either as single/multiple infections. HPV 18 and HPV 16 were the predominant genotypes among HIV positive and HIV negative subjects respectively. Oncogenic HPV was not found to be associated with age and duration of sexual exposure. But the presence of HIV was found to a statistically significant predictor oncogenic HPV. Conclusion The currently available HPV vaccines offer protection only against HPV 16 and 18 and some cross- protection to few associated genotypes. These vaccines are therefore less likely to offer protection against cervical cancer in HIV positive women a high percentage of who were infected with non-16 and non-18 oncogenic HPV genotypes. Additionally, there is a lack of sufficient evidence of immunogenicity in HIV infected individuals. Therefore

  13. Targeting CK2-driven non-oncogene addiction in B-cell tumors.

    Science.gov (United States)

    Mandato, E; Manni, S; Zaffino, F; Semenzato, G; Piazza, F

    2016-11-24

    Genetic mutations of oncogenes often underlie deranged cell growth and altered differentiation pathways leading to malignant transformation of B-lymphocytes. However, addiction to oncogenes is not the only drive to lymphoid tumor pathogenesis. Dependence on non-oncogenes, which act by propelling basic mechanisms of cell proliferation and survival, has also been recognized in the pathobiology of lymphoid leukemias, lymphomas and multiple myeloma. Among the growing number of molecules that may uphold non-oncogene addiction, a key place is increasingly being recognized to the serine-threonine kinase CK2. This enzyme is overexpressed and overactive in B-acute lymphoblastic leukemia, multiple myeloma, chronic lymphocytic leukemia and non-Hodgkin lymphomas, such as mantle cell, follicular, Burkitt's and diffuse large B-cell lymphomas. In these tumors, CK2 may serve the activity of oncogenes, similar to BCR-ABL and c-MYC, control the activation of critical signaling cascades, such as NF-κB (nuclear factor-κB), STAT3 (signal transducer and activator of transcription 3) and PTEN/PI3K/AKT (phosphatase and tensin homolog protein/phosphoinositide 3-kinase/AKR thymoma), and sustain multiple cellular stress-elicited pathways, such as the proteotoxic stress, unfolded protein and DNA-damage responses. CK2 has also been shown to have an essential role in tuning signals derived from the stromal tumor microenvironment. Not surprisingly, targeting CK2 in lymphoid tumor cell lines or mouse xenograft models can boost the cytotoxic effects of both conventional chemotherapeutics and novel agents, similar to heat-shock protein 90, proteasome and tyrosine kinases inhibitors. In this review, we summarize the evidence indicating how CK2 embodies most of the features of a cancer growth-promoting non-oncogene, focusing on lymphoid tumors. We further discuss the preclinical data of the use of small ATP-competitive CK2 inhibitors, which hold the promise to be additional options in novel drug

  14. BCL3 exerts an oncogenic function by regulating STAT3 in human cervical cancer

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    Zhao H

    2016-10-01

    Full Text Available Hu Zhao,1 Wuliang Wang,1 Qinghe Zhao,1 Guiming Hu,2 Kehong Deng,1 Yuling Liu1 1Department of Gynecology and Obstetrics, 2Department of Pathology, The Second Affiliated Hospital of Zhengzhou University, Zhengzhou, People’s Republic of China Abstract: Aberrant expression of oncogenes and/or tumor suppressors play a fundamental effect on the pathogenesis and tumorigenicity of cervical cancer (CC. B-cell CLL/lymphoma 3 (BCL3 was previously found to be a putative proto-oncogene in human cancers and regulated signal transducer and activator of transcription 3 (STAT3, a critical oncogene, in CC cell line. However, its expression status, clinical significance and biological functions in CC remain largely unclear. The expressions of BCL3 and STAT3 in CC specimens were determined by immunohistochemistry. MTT, colony formation assays and flow cytometry analysis were carried out to test proliferation and cell cycle of CC cells. Here, the levels of BCL3 were overexpressed in CC compared to adjacent cervical tissues. Furthermore, high levels of BCL3 protein were confirmed by immunoblotting in CC cells as compared with normal cervical epithelial cells. The positive expression of BCL3 was correlated with adverse prognostic features and reduced survival rate. In addition, BCL3 regulated STAT3 abundance in CC cells. STAT3 was found to be upregulated and positively correlated with BCL3 expression in CC specimens. BCL3 overexpression resulted in prominent increased proliferation and cell cycle progression in Hela cells. By contrast, inhibition of BCL3 in CaSki cells remarkably suppressed proliferative ability and cell cycle progression. In vivo studies showed that knockdown of BCL3 inhibited tumor growth of CC in mice xenograft model. Notably, we confirmed that STAT3 mediated the oncogenic roles of BCL3 in CC. In conclusion, we suggest that BCL3 serves as an oncogene in CC by modulating proliferation and cell cycle progression, and its oncogenic effect is

  15. Liver tumors induced in B6C3F{sub 1} mice by benz[a]anthracene and two of its halogenated derivatives contain K-RAS oncogene mutations

    Energy Technology Data Exchange (ETDEWEB)

    Xia, O.; Yi, P.; Zhan, D. [and others

    1997-10-01

    Polycyclic aromatic hydrocarbons (PAHs) and halogenated PAHs are genotoxic environmental contaminants. We previously examined the tumorigenicity of benz[a]anthracene (BA), 7-Cl-BA, and 7-Br-BA in the neonatal mouse tumorigenicity bioassay. Male B6C3F{sub 1} mice were administered i.p. injections at a total dose of 400 nmol per mouse on 1, 8, and 15 days after birth. BA, 7-Cl-BA, and 7-Br-BA induced hepatocellular adenoma in 67, 92, and 96% of the mice, respectively, and induced hepatocellular carcinoma in 15, 100 and 83% of the mice, respectively. In the present study, mRNA was isolated from each of the liver tumors induced by the three compounds, reversed-transcribed to cDNA, and portions of the K- and H-ras oncogene coding sequences were amplified and analyzed for DNA sequence alterations. 92% (11/12) of BA-induced, 79% (19/24) of 7-Cl-BA-induced and 86% (19/22) of 7-Br-BA-induced liver tumors had activated ras protooncogenes. In contrast to the general finding of H-ras mutations in B6C3F{sub 1} mouse liver tumors, all the mutations were at the first base of K-ras codon 13, resulting in a pattern of GGC{yields}CGC. No other ras oncogene mutations were detected. Our results clearly demonstrate that these chemicals induce a unique type of ras (K-ras) oncogene activation in the liver tumors of B6C3F{sub 1} mice.

  16. mRNA pseudoknot structures can act as ribosomal roadblocks

    DEFF Research Database (Denmark)

    Hansen, Jesper Tholstrup; Oddershede, Lene Broeng; Sørensen, Michael Askvad

    2012-01-01

    Several viruses utilize programmed ribosomal frameshifting mediated by mRNA pseudoknots in combination with a slippery sequence to produce a well defined stochiometric ratio of the upstream encoded to the downstream-encoded protein. A correlation between the mechanical strength of mRNA pseudoknot...

  17. Functional Integration of mRNA Translational Control Programs

    Directory of Open Access Journals (Sweden)

    Melanie C. MacNicol

    2015-07-01

    Full Text Available Regulated mRNA translation plays a key role in control of cell cycle progression in a variety of physiological and pathological processes, including in the self-renewal and survival of stem cells and cancer stem cells. While targeting mRNA translation presents an attractive strategy for control of aberrant cell cycle progression, mRNA translation is an underdeveloped therapeutic target. Regulated mRNAs are typically controlled through interaction with multiple RNA binding proteins (RBPs but the mechanisms by which the functions of distinct RBPs bound to a common target mRNA are coordinated are poorly understood. The challenge now is to gain insight into these mechanisms of coordination and to identify the molecular mediators that integrate multiple, often conflicting, inputs. A first step includes the identification of altered mRNA ribonucleoprotein complex components that assemble on mRNAs bound by multiple, distinct RBPs compared to those recruited by individual RBPs. This review builds upon our knowledge of combinatorial control of mRNA translation during the maturation of oocytes from Xenopus laevis, to address molecular strategies that may mediate RBP diplomacy and conflict resolution for coordinated control of mRNA translational output. Continued study of regulated ribonucleoprotein complex dynamics promises valuable new insights into mRNA translational control and may suggest novel therapeutic strategies for the treatment of disease.

  18. Probing dimensionality beyond the linear sequence of mRNA.

    Science.gov (United States)

    Del Campo, Cristian; Ignatova, Zoya

    2016-05-01

    mRNA is a nexus entity between DNA and translating ribosomes. Recent developments in deep sequencing technologies coupled with structural probing have revealed new insights beyond the classic role of mRNA and place it more centrally as a direct effector of a variety of processes, including translation, cellular localization, and mRNA degradation. Here, we highlight emerging approaches to probe mRNA secondary structure on a global transcriptome-wide level and compare their potential and resolution. Combined approaches deliver a richer and more complex picture. While our understanding on the effect of secondary structure for various cellular processes is quite advanced, the next challenge is to unravel more complex mRNA architectures and tertiary interactions.

  19. 三氯乙烯药疹样皮炎病人外周血c-fos、c-myc、K-ras和p53mRNA表达水平的研究%mRNA expression of oncogenes in patients with allergic dermatitis induced by trichloroethylene

    Institute of Scientific and Technical Information of China (English)

    徐新云; 刘月峰; 易娟; 周丽; 黄新凤; 毛吉炎; 毛侃琅

    2012-01-01

    目的:探讨三氯乙烯(trichloroethylene,TCE)药疹样皮炎病人外周血癌基因c-fos、c-myc、K-ras、p53 mRNA表达水平的变化情况.方法:分别抽取4例健康人(对照组)及4例三氯乙烯致变态反应病人(病例组)抗凝外周全血,采用实时荧光定量PCR(real-time quantitative PCR)技术检测外周血中c-fos、c-myc、K-ras和p53 mRNA的表达水平.结果:与健康对照者比较,三氯乙烯药疹样皮炎病人外周血c-fos mRNA表达水平升高352%,c-myc mRNA升高41%,K-ras mRNA升高136%,p53 mRNA升高64%,两组间上述基因mRNA表达水平的差异均有统计学意义(P<0.01或P<0.05).结论:三氯乙烯药疹样皮炎病人外周血癌基因表达水平增加,提示三氯乙烯可能有一定的致癌风险.%OBJECTIVE: To study mRNA expression of oncogenes (c-fos, c-myc, K-ras, p53) in peripheral blood of patients allergic to trichloroethylene (TCE). METHODS: Peripheral blood samples were collected from healthy workers (control group) and allergic patients (case group). Real-time quantitative PCR was applied to detect mRNA expression of oncogenes c-fos, c-myc, K-ras, p53. RESULTS: The level of c-fos mRNA expression increased by 352% in TCE patients when compared with control (P<0.01), c-myc increased by 41%, K-ras by 136% and p53 increased by 64%. mRNA expression levels of these oncogenes showed significant differences between case and control groups (P<0.01 or P<0.05). CONCLUSION: Trichloroethylene could induce oncogene expression in patients with allergic dermatitis, indicating that TCE might be potentially carcinogenic.

  20. Oncogenic transformation through the cell cycle and the LET dependent inverse dose rate effect

    Science.gov (United States)

    Geard, C. R.; Miller, R. C.; Brenner, D. J.; Hall, E. J.; Wachholz, B. W. (Principal Investigator)

    1994-01-01

    Synchronised populations of mouse C3H/10T-1/2 cells were obtained by a stringent mitotic dislodgment procedure. Mitotic cells rapidly attach and progress sequentially through the cell cycle. Irradiation (3 Gy of X rays) was carried out at intervals from 0 to 18 h after initiating cell cycle progression of the mitotic cells. Oncogenic transformation was enhanced 10-fold over cells irradiated soon after replating (G1 and S phases) for cells in a near 2 h period corresponding to cells in G2 phase but not in mitosis. The cell surviving fraction had a 2-1/2-fold variation with resistant peaks corresponding to the late G1 and late S phases. These findings provide experimental support for the hypothesis initiated by Rossi and Kellerer and developed by Brenner and Hall to explain the LET dependent inverse dose rate effect for oncogenic transformation.

  1. Tumor suppression by miR-26 overrides potential oncogenic activity in intestinal tumorigenesis

    Science.gov (United States)

    Zeitels, Lauren R.; Acharya, Asha; Shi, Guanglu; Chivukula, Divya; Chivukula, Raghu R.; Anandam, Joselin L.; Abdelnaby, Abier A.; Balch, Glen C.; Mansour, John C.; Yopp, Adam C.; Richardson, James A.

    2014-01-01

    Down-regulation of miR-26 family members has been implicated in the pathogenesis of multiple malignancies. In some settings, including glioma, however, miR-26-mediated repression of PTEN promotes tumorigenesis. To investigate the contexts in which the tumor suppressor versus oncogenic activity of miR-26 predominates in vivo, we generated miR-26a transgenic mice. Despite measureable repression of Pten, elevated miR-26a levels were not associated with malignancy in transgenic animals. We documented reduced miR-26 expression in human colorectal cancer and, accordingly, showed that miR-26a expression potently suppressed intestinal adenoma formation in Apcmin/+ mice, a model known to be sensitive to Pten dosage. These studies reveal a tumor suppressor role for miR-26 in intestinal cancer that overrides putative oncogenic activity, highlighting the therapeutic potential of miR-26 delivery to this tumor type. PMID:25395662

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

    Science.gov (United States)

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

    2012-03-01

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

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

    Directory of Open Access Journals (Sweden)

    Conan Kinsey

    2014-05-01

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

  4. Repurposing a Prokaryotic Toxin-Antitoxin System for the Selective Killing of Oncogenically Stressed Human Cells.

    Science.gov (United States)

    Preston, Mark A; Pimentel, Belén; Bermejo-Rodríguez, Camino; Dionne, Isabelle; Turnbull, Alice; de la Cueva-Méndez, Guillermo

    2016-07-15

    Prokaryotes express intracellular toxins that pass unnoticed to carrying cells until coexpressed antitoxin partners are degraded in response to stress. Although not evolved to function in eukaryotes, one of these toxins, Kid, induces apoptosis in mammalian cells, an effect that is neutralized by its cognate antitoxin, Kis. Here we engineered this toxin-antitoxin pair to create a synthetic system that becomes active in human cells suffering a specific oncogenic stress. Inspired by the way Kid becomes active in bacterial cells, we produced a Kis variant that is selectively degraded in human cells expressing oncoprotein E6. The resulting toxin-antitoxin system functions autonomously in human cells, distinguishing those that suffer the oncogenic insult, which are killed by Kid, from those that do not, which remain protected by Kis. Our results provide a framework for developing personalized anticancer strategies avoiding off-target effects, a challenge that has been hardly tractable by other means thus far.

  5. MiR-191 Regulates Primary Human Fibroblast Proliferation and Directly Targets Multiple Oncogenes.

    Directory of Open Access Journals (Sweden)

    Damon Polioudakis

    Full Text Available miRNAs play a central role in numerous pathologies including multiple cancer types. miR-191 has predominantly been studied as an oncogene, but the role of miR-191 in the proliferation of primary cells is not well characterized, and the miR-191 targetome has not been experimentally profiled. Here we utilized RNA induced silencing complex immunoprecipitations as well as gene expression profiling to construct a genome wide miR-191 target profile. We show that miR-191 represses proliferation in primary human fibroblasts, identify multiple proto-oncogenes as novel miR-191 targets, including CDK9, NOTCH2, and RPS6KA3, and present evidence that miR-191 extensively mediates target expression through coding sequence (CDS pairing. Our results provide a comprehensive genome wide miR-191 target profile, and demonstrate miR-191's regulation of primary human fibroblast proliferation.

  6. RNA-DNA differences are rarer in proto-oncogenes than in tumor suppressor genes.

    Science.gov (United States)

    Gao, Feng; Lin, Yan; Zhang, Randy Ren

    2012-01-01

    It has long been assumed that DNA sequences and corresponding RNA transcripts are almost identical; a recent discovery, however, revealed widespread RNA-DNA differences (RDDs), which represent a largely unexplored aspect of human genome variation. It has been speculated that RDDs can affect disease susceptibility and manifestations; however, almost nothing is known about how RDDs are related to disease. Here, we show that RDDs are rarer in proto-oncogenes than in tumor suppressor genes; the number of RDDs in coding exons, but not in 3'UTR and 5'UTR, is significantly lower in the former than the latter, and this trend is especially pronounced in non-synonymous RDDs, i.e., those cause amino acid changes. A potential mechanism is that, unlike proto-oncogenes, the requirement of tumor suppressor genes to have both alleles affected to cause tumor 'buffers' these genes to tolerate more RDDs.

  7. MiR-191 Regulates Primary Human Fibroblast Proliferation and Directly Targets Multiple Oncogenes.

    Science.gov (United States)

    Polioudakis, Damon; Abell, Nathan S; Iyer, Vishwanath R

    2015-01-01

    miRNAs play a central role in numerous pathologies including multiple cancer types. miR-191 has predominantly been studied as an oncogene, but the role of miR-191 in the proliferation of primary cells is not well characterized, and the miR-191 targetome has not been experimentally profiled. Here we utilized RNA induced silencing complex immunoprecipitations as well as gene expression profiling to construct a genome wide miR-191 target profile. We show that miR-191 represses proliferation in primary human fibroblasts, identify multiple proto-oncogenes as novel miR-191 targets, including CDK9, NOTCH2, and RPS6KA3, and present evidence that miR-191 extensively mediates target expression through coding sequence (CDS) pairing. Our results provide a comprehensive genome wide miR-191 target profile, and demonstrate miR-191's regulation of primary human fibroblast proliferation.

  8. DNA Oncogenic Virus-Induced Oxidative Stress, Genomic Damage, and Aberrant Epigenetic Alterations

    Directory of Open Access Journals (Sweden)

    Mankgopo Magdeline Kgatle

    2017-01-01

    Full Text Available Approximately 20% of human cancers is attributable to DNA oncogenic viruses such as human papillomavirus (HPV, hepatitis B virus (HBV, and Epstein-Barr virus (EBV. Unrepaired DNA damage is the most common and overlapping feature of these DNA oncogenic viruses and a source of genomic instability and tumour development. Sustained DNA damage results from unceasing production of reactive oxygen species and activation of inflammasome cascades that trigger genomic changes and increased propensity of epigenetic alterations. Accumulation of epigenetic alterations may interfere with genome-wide cellular signalling machineries and promote malignant transformation leading to cancer development. Untangling and understanding the underlying mechanisms that promote these detrimental effects remain the major objectives for ongoing research and hope for effective virus-induced cancer therapy. Here, we review current literature with an emphasis on how DNA damage influences HPV, HVB, and EBV replication and epigenetic alterations that are associated with carcinogenesis.

  9. Immortalized cells and one oncogene in malignant transformation: old insights on new explanation

    Science.gov (United States)

    2011-01-01

    Background Nearly thirty years ago, it was first shown that malignant transformation with single oncogene necessarily requires the immortal state of the cell. From that time this thesis for the cells of human origin was not disproved. The basic point which we want to focus on by this short communication is the correct interpretation of the results obtained on the widely used human embryonic kidney 293 (HEK293) cells. Results Intensive literature analysis revealed an increasing number of recent studies discovering new oncogenes with non-overlapping functions. Since the 1970s, dozens of oncogenes have been identified in human cancer. Cultured cell lines are often used as model systems in these experiments. In some investigations the results obtained on such cells are interpreted by the authors as a malignant transformation of normal animal or even normal human cells (as for example with HEK293 cells). However, when a cell line gains the ability to undergo continuous cell division, the cells are not normal any more, they are immortalized cells. Nevertheless, the authors consider these cells as normal human ones, what is basically incorrect. Moreover, it was early demonstrated that the widely used human embryonic kidney 293 (HEK293) cells have a relationship to neurons. Conclusions Thus, the experiments with established cell lines reinforce the notion that immortality is an essential requirement for malignant transformation that cooperates with other oncogenic changes to program the neoplastic state and substances under such investigation should be interpreted as factors which do not malignantly transform normal cells alone, but possess the ability to enhance the tumorigenic potential of already immortalized cells. PMID:21605454

  10. Activation of cellular oncogenes by chemical carcinogens in Syrian hamster embryo fibroblasts

    Energy Technology Data Exchange (ETDEWEB)

    Ebert, R.; Reiss, E.; Roellich, G.; Schiffmann, D. (Univ. of Wuerzburg (West Germany)); Barrett, J.C.; Wiseman, R.W. (National Institute of Environmental Health Sciences, Research Triangle Park, NC (USA)); Pechan, R.

    1990-08-01

    Carcinogen-induced point mutations resulting in activation of ras oncogenes have been demonstrated in various experimental systems such as skin carcinogenesis, mammary, and liver carcinogenesis. In many cases, the data support the conclusion that these point mutations are critical changes in the initiation of these tumors. The Syrian hamster embryo (SHE) cell transformation model system has been widely used to study the multistep process of chemically induced neoplastic transformation. Recent data suggest that activation of the Ha-ras gene via point mutation is one of the crucial events in the transformation of these cells. The authors have now cloned the c-Ha-ras proto-oncogene from SHE cDNA-libraries, and we have performed polymerase chain reaction and direct sequencing to analyze tumor cell lines induced by different chemical carcinogens for the presence of point mutations. No changes were detectable at codons 12, 13, 59, 61, and 117 or adjacent regions in tumor cell lines induced by diethylstilbestrol, asbestos, benzo(a)pyrene, trenbolone, or aflatoxin B{sub 1}. Thus, it is not known whether point mutations in the Ha-ras proto-oncogene are essential for the acquisition of the neoplastic phenotype of SHE cells. Activation of other oncogenes or inactivation of tumor suppressor genes may be responsible for the neoplastic progression of these cells. However, in SHE cells neoplastically transformed by diethylstilbestrol or trenbolone, a significant elevation of the c-Ha-ras expression was observed. Enhanced expression of c-myc was detected in SHE cells transformed by benzo(a)pyrene or trenbolone.

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

    Science.gov (United States)

    2015-10-01

    elements in prostate cancer contribute to its progression by activating oncogenic DNA sequences, or silencing tumor suppressor like sequences. We have...the use of animals and the use of recombinant DNA /lentiviral vectors. All of these approvals have now been obtained. For Task 1, we cloned the LINE...Books or other non-periodical, one-time publications. Report any book, monograph , dissertation, abstract, or the like published as or in a

  12. Cooperativity Between Oncogenic PKC Epsilon and Pten Loss in Prostate Cancer Progression

    Science.gov (United States)

    2015-10-01

    initiated studies to dissect the signaling mechanisms that mediate CXCL13 induction. We took advantage of a cellular model that we generated in our...metastatic loop that is mediated by CXCL13. We also hypothesize that PKCε is a CXCL13:CXCR5 effector that contributes to positively amplify this oncogenic...shown). Therefore, it is possible that an autocrine CXCL13:CXCR5 loop mediates effects driven by PKCε overexpression and Pten loss. * * R el at iv

  13. PTPN14 interacts with and negatively regulates the oncogenic function of YAP

    OpenAIRE

    Liu, X; Yang, N; Figel, SA; Wilson, KE; Morrison, CD; Gelman, IH; Zhang, J

    2012-01-01

    The Hippo signaling pathway regulates cellular proliferation and survival, thus exerting profound effects on normal cell fate and tumorigenesis. The pivotal effector of this pathway is YAP, a transcriptional co-activator amplified in mouse and human cancers where it promotes epithelial-to-mesenchymal transition and malignant transformation. Here, we report a novel regulatory mechanism for the YAP oncogenic function via direct interaction with non-receptor tyrosine phosphatase 14 (PTPN14) thro...

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

    Directory of Open Access Journals (Sweden)

    Christoph Campregher

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

  15. Nuclear Localization and DNA Binding Properties of a Protein Expressed by Human c-myc Oncogene

    Science.gov (United States)

    Persson, Hakan; Leder, Philip

    1984-08-01

    Antisera to the human cellular myc oncogene product were used to identify a human c-myc specific protein with a molecular weight of 65,000. Subcellular fractionation showed that the human c-myc protein is predominantly found in the cell nucleus. The p65 Kc-myc protein binds to double- and single-stranded DNA as measured by a DNA affinity chromatography assay.

  16. Oncogenic HPV among HIV infected female population in West Bengal, India

    OpenAIRE

    Sengupta Sharmila; Bhattacharya Subhasish; Saha Bibhuti; Bal Baishali; Pal Reshmi; Sarkar Kamalesh; Mazumdar Partha; Chakraborti Shekhar

    2011-01-01

    Abstract Background Prevalence of both cervical cancer and Human Immunodeficiency Virus (HIV) infection are very high in India. Natural history of Human Papilloma Virus (HPV) infection is known to be altered in HIV positive women and there is an increased possibility of persistence of HPV infections in this population. Therefore, this study was conducted to understand the epidemiology and circulating genotypes of oncogenic HPV among HIV positive and negative female population in West Bengal, ...

  17. Expression Profiling of Circulating Microvesicles Reveals Intercellular Transmission of Oncogenic Pathways.

    Science.gov (United States)

    Milani, Gloria; Lana, Tobia; Bresolin, Silvia; Aveic, Sanja; Pastò, Anna; Frasson, Chiara; Te Kronnie, Geertruy

    2017-06-01

    Circulating microvesicles have been described as important players in cell-to-cell communication carrying biological information under normal or pathologic condition. Microvesicles released by cancer cells may incorporate diverse biomolecules (e.g., active lipids, proteins, and RNA), which can be delivered and internalized by recipient cells, potentially altering the gene expression of recipient cells and eventually impacting disease progression. Leukemia in vitro model systems were used to investigate microvesicles as vehicles of protein-coding messages. Several leukemic cells (K562, LAMA-87, TOM-1, REH, and SHI-1), each carrying a specific chromosomal translocation, were analyzed. In the leukemic cells, these chromosomal translocations are transcribed into oncogenic fusion transcripts and the transfer of these transcripts was monitored from leukemic cells to microvesicles for each of the cell lines. Microarray gene expression profiling was performed to compare transcriptomes of K562-derived microvesicles and parental K562 cells. The data show that oncogenic BCR-ABL1 transcripts and mRNAs related to basic functions of leukemic cells were included in microvesicles. Further analysis of microvesicles cargo revealed a remarkable enrichment of transcripts related to cell membrane activity, cell surface receptors, and extracellular communication when compared with parental K562 cells. Finally, coculturing of healthy mesenchymal stem cells (MSC) with K562-derived microvesicles displayed the transfer of the oncogenic message, and confirmed the increase of target cell proliferation as a function of microvesicle dosage.Implications: This study provides novel insight into tumor-derived microvesicles as carriers of oncogenic protein-coding messages that can potentially jeopardize cell-directed therapy, and spread to other compartments of the body. Mol Cancer Res; 15(6); 683-95. ©2017 AACR. ©2017 American Association for Cancer Research.

  18. Detection of FLT3 Oncogene Mutations in Acute Myeloid Leukemia Using Conformation Sensitive Gel Electrophoresis

    OpenAIRE

    2008-01-01

    FLT3 (fms-related tyrosine kinase 3) is a receptor tyrosine kinase class III that is expressed on by early hematopoietic progenitor cells and plays an important role in hematopoietic stem cell proliferation, differentiation and survival. FLT3 is also expressed on leukemia blasts in most cases of acute myeloid leukemia (AML). In order to determine the frequency of FLT3 oncogene mutations, we analyzed genomic DNA of adult de novo acute myeloid leukemia (AML). Polymerase chain reaction (PCR) and...

  19. Oncogenic KRAS activates an embryonic stem cell-like program in human colon cancer initiation

    OpenAIRE

    Le Rolle, Anne-France; Chiu, Thang K; ZENG, ZHAOSHI; Shia, Jinru; Weiser, Martin R; Paty, Philip B.; Chiu, Vi K

    2016-01-01

    Colorectal cancer is the third most frequently diagnosed cancer worldwide. Prevention of colorectal cancer initiation represents the most effective overall strategy to reduce its associated morbidity and mortality. Activating KRAS mutation (KRASmut ) is the most prevalent oncogenic driver in colorectal cancer development, and KRASmut inhibition represents an unmet clinical need. We apply a systems-level approach to study the impact of KRASmut on stem cell signaling during human colon cancer i...

  20. Oncogenic Alternative Splicing Switches: Role in Cancer Progression and Prospects for Therapy

    OpenAIRE

    Serena Bonomi; Stefania Gallo; Morena Catillo; Daniela Pignataro; Giuseppe Biamonti; Claudia Ghigna

    2013-01-01

    Alterations in the abundance or activities of alternative splicing regulators generate alternatively spliced variants that contribute to multiple aspects of tumor establishment, progression and resistance to therapeutic treatments. Notably, many cancer-associated genes are regulated through alternative splicing suggesting a significant role of this post-transcriptional regulatory mechanism in the production of oncogenes and tumor suppressors. Thus, the study of alternative splicing in cancer ...

  1. Oncogenic action of beta, proton, alpha and electron radiation on the rat skin

    Energy Technology Data Exchange (ETDEWEB)

    Burns, F.J.

    1980-01-01

    Rat skin is being utilized as an empirical model for testing dose and time related aspects of the oncogenic action of ionizing radiation, ultraviolet light, and polycyclic aromatic hydrocarbons. Molecular lesions in the skin DNA, including, strand breaks and thymine dimers, are being measured and compared to tumor induction. The induction and repair kinetics of molcular lesions are being compared to split dose repair. Modifiers and radiosensitizers are being utilized to test specific aspects of a chromosome breakage theory of radiation oncogenesis.

  2. Mutation of RET proto-oncogene in Hirschsprung's disease and intestinal neuronal dysplasia

    Institute of Scientific and Technical Information of China (English)

    Jin-Fa Tou; Min-Ju Li; Tao Guan; Ji-Cheng Li; Xiong-Kai Zhu; Zhi-Gang Feng

    2006-01-01

    AIM: To investigate the genetic relationship between Hirschsprung's disease (HD) and intestinal neuronal dysplasia (IND) in Chinese population.METHODS: Peripheral blood samples were obtained from 30 HD patients, 20 IND patients, 18 HD/IND combined patients and 20 normal individuals as control.Genomic DNA was extracted according to standard procedure. Exons 11,13,15,17 of RET proto-oncogene were amplified by polymerase chain reaction (PCR).The mutations of RET proto-oncogene were analyzed by single strand conformational polymorphism (SSCP)and sequencing of the positive amplified products was performed.RESULTS: Eight germline sequence variants were detected. In HD patients, 2 missense mutations in exon 11at nucleotide 15165 G→A (G667S), 2 frameshift mutations in exon 13 at nucleotide 18974 (18974insG), 1missense mutation in exon 13 at nucleotide 18919 A→G (K756E) and 1silent mutation in exon 15 at nucleotide 20692 G→A(Q916Q) were detected. In HD/IND combined patients, 1 missense mutation in exon 11 at nucleotide 15165 G→A and 1 silent mutation in exon 13at nucleotide 18888 T→G (L745L) were detected. No mutation was found in IND patients and controls.CONCLUSION: Mutation of RET proto-oncogene is involved in the etiopathogenesis of HD. The frequency of RET proto-oncogene mutation is quite different between IND and HD in Chinese population. IND is a distinct clinical entity genetically different from HD.

  3. Exosomes enriched in stemness/metastatic-related mRNAS promote oncogenic potential in breast cancer

    OpenAIRE

    2015-01-01

    Cancer cells efficiently transfer exosome contents (essentially mRNAs and microRNAs) to other cell types, modifying immune responses, cell growth, angiogenesis and metastasis. Here we analyzed the exosomes release by breast tumor cells with different capacities of stemness/metastasis based on CXCR4 expression, and evaluated their capacity to generate oncogenic features in recipient cells. Breast cancer cells overexpressing CXCR4 showed an increase in stemness-related markers, and in prolifera...

  4. Clinical performance of human papillomavirus E6, E7 mRNA flow cytometric assay compared to human papillomavirus DNA typing.

    Science.gov (United States)

    Kottaridi, Christine; Tsiodras, Sotirios; Spathis, Aris; Chranioti, Aikaterini; Pappas, Asimakis; Kassanos, Dimitrios; Panayiotides, Ioannis; Karakitsos, Petros

    2011-12-01

    To use flow cytometry to screen cervical samples for the overexpression of human papillomavirus (HPV) E6 and E7 mRNA and compare the performance of this assay with an HPV DNA array for the detection of high-grade cervical lesions. Cervical samples were analyzed for HPV DNA by clinical arrays, and the overexpression of E6 and E7 viral oncogenes was monitored using an HPV mRNA detection kit that quantifies the intracellular HPV E6 and E7 mRNA on a cell-by-cell basis. HPV positivity increased with severity of histologic lesions. On the basis of histology-confirmed CIN 2+ cases the specificity of HPV assay was 73.9% (95% CI 66.07, 80.88), whereas it was 39.3% (95% CI 31.85, 47.1) for the DNA assay. The HPV assay provides an early predictor of persistent HPV infection and may improve cervical cancer screening by increasing the specificity of detecting high-grade lesions.

  5. Panaxquin quefolium diolsaponins dose-dependently inhibits the proliferation of vascular smooth muscle cells by downregulating proto-oncogene expression

    Directory of Open Access Journals (Sweden)

    Zhihao Wang

    2013-01-01

    Conclusions: Our study demonstrates that PQDS may reduce AngII-stimulated VSMC proliferation by suppressing the expression of proto-oncogenes. These results may provide insights for the development of novel traditional Chinese medicines to prevent atherosclerosis.

  6. A human cellular sequence implicated in trk oncogene activation is DNA damage inducible

    Energy Technology Data Exchange (ETDEWEB)

    Ben-Ishai, R.; Scharf, R.; Sharon, R.; Kapten, I. (Technion-Israel Institute of Technology, Haifa (Israel))

    1990-08-01

    Xeroderma pigmentosum cells, which are deficient in the repair of UV light-induced DNA damage, have been used to clone DNA-damage-inducible transcripts in human cells. The cDNA clone designated pC-5 hybridizes on RNA gel blots to a 1-kilobase transcript, which is moderately abundant in nontreated cells and whose synthesis is enhanced in human cells following UV irradiation or treatment with several other DNA-damaging agents. UV-enhanced transcription of C-5 RNA is transient and occurs at lower fluences and to a greater extent in DNA-repair-deficient than in DNA-repair-proficient cells. Southern blot analysis indicates that the C-5 gene belongs to a multigene family. A cDNA clone containing the complete coding sequence of C-5 was isolated. Sequence analysis revealed that it is homologous to a human cellular sequence encoding the amino-terminal activating sequence of the trk-2h chimeric oncogene. The presence of DNA-damage-responsive sequences at the 5' end of a chimeric oncogene could result in enhanced expression of the oncogene in response to carcinogens.

  7. Features and Usage Areas of MicroRNAs as Oncogenes and Tumor Suppressors

    Directory of Open Access Journals (Sweden)

    G. Seyda Seydel

    2009-02-01

    Full Text Available MicroRNAs (miRNA are small non-coding RNA of 19–24 nucleotides in length that were discovered 12 years ago by Victor Ambros and colleagues. They are important regulatory molecules in animals and plants. MicroRNAs are downregulate gene expression during various crucial cell processes such as apoptosis, differentiation and development. In addition, some miRNAs may function as oncogenes or tumor suppressors. More than 50% of miRNA genes are located in cancer-associated genomic regions or in fragile sites. Overexpressed miRNAs in cancers, such as mir17–92, may function as oncogenes and promote cancer development by negatively regulating tumor suppressor genes and genes that control cell differentiation or apoptosis. Underexpressed miRNAs in cancers, such as let–7, function as tumor suppressor genes and may inhibit cancers by regulating oncogenes and genes that control cell differentiation or apoptosis. miRNA expression profiles may become useful biomarkers for cancer diagnostics. [Archives Medical Review Journal 2009; 18(1.000: 1-12

  8. HER2 missense mutations have distinct effects on oncogenic signaling and migration

    Science.gov (United States)

    Zabransky, Daniel J.; Yankaskas, Christopher L.; Cochran, Rory L.; Wong, Hong Yuen; Croessmann, Sarah; Chu, David; Kavuri, Shyam M.; Red Brewer, Monica; Rosen, D. Marc; Dalton, W. Brian; Cimino-Mathews, Ashley; Cravero, Karen; Button, Berry; Kyker-Snowman, Kelly; Cidado, Justin; Erlanger, Bracha; Parsons, Heather A.; Manto, Kristen M.; Bose, Ron; Lauring, Josh; Arteaga, Carlos L.; Konstantopoulos, Konstantinos; Park, Ben Ho

    2015-01-01

    Recurrent human epidermal growth factor receptor 2 (HER2) missense mutations have been reported in human cancers. These mutations occur primarily in the absence of HER2 gene amplification such that most HER2-mutant tumors are classified as “negative” by FISH or immunohistochemistry assays. It remains unclear whether nonamplified HER2 missense mutations are oncogenic and whether they are targets for HER2-directed therapies that are currently approved for the treatment of HER2 gene-amplified breast cancers. Here we functionally characterize HER2 kinase and extracellular domain mutations through gene editing of the endogenous loci in HER2 nonamplified human breast epithelial cells. In in vitro and in vivo assays, the majority of HER2 missense mutations do not impart detectable oncogenic changes. However, the HER2 V777L mutation increased biochemical pathway activation and, in the context of a PIK3CA mutation, enhanced migratory features in vitro. However, the V777L mutation did not alter in vivo tumorigenicity or sensitivity to HER2-directed therapies in proliferation assays. Our results suggest the oncogenicity and potential targeting of HER2 missense mutations should be considered in the context of cooperating genetic alterations and provide previously unidentified insights into functional analysis of HER2 mutations and strategies to target them. PMID:26508629

  9. Transglutaminase 2 contributes to a TP53-induced autophagy program to prevent oncogenic transformation.

    Science.gov (United States)

    Yeo, Shi Yun; Itahana, Yoko; Guo, Alvin Kunyao; Han, Rachel; Iwamoto, Kozue; Nguyen, Hung Thanh; Bao, Yi; Kleiber, Kai; Wu, Ya Jun; Bay, Boon Huat; Voorhoeve, Mathijs; Itahana, Koji

    2016-03-09

    Genetic alterations which impair the function of the TP53 signaling pathway in TP53 wild-type human tumors remain elusive. To identify new components of this pathway, we performed a screen for genes whose loss-of-function debilitated TP53 signaling and enabled oncogenic transformation of human mammary epithelial cells. We identified transglutaminase 2 (TGM2) as a putative tumor suppressor in the TP53 pathway. TGM2 suppressed colony formation in soft agar and tumor formation in a xenograft mouse model. The depletion of growth supplements induced both TGM2 expression and autophagy in a TP53-dependent manner, and TGM2 promoted autophagic flux by enhancing autophagic protein degradation and autolysosome clearance. Reduced expression of both CDKN1A, which regulates the cell cycle downstream of TP53, and TGM2 synergized to promote oncogenic transformation. Our findings suggest that TGM2-mediated autophagy and CDKN1A-mediated cell cycle arrest are two important barriers in the TP53 pathway that prevent oncogenic transformation.

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

    Directory of Open Access Journals (Sweden)

    Sonia Kaniuka-Jakubowska

    2012-08-01

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

  11. Notch promotes epithelial-mesenchymal transition during cardiac development and oncogenic transformation

    Science.gov (United States)

    Timmerman, Luika A.; Grego-Bessa, Joaquín; Raya, Angel; Bertrán, Esther; Pérez-Pomares, José María; Díez, Juan; Aranda, Sergi; Palomo, Sergio; McCormick, Frank; Izpisúa-Belmonte, Juan Carlos; de la Pompa, José Luis

    2004-01-01

    Epithelial-to-mesenchymal transition (EMT) is fundamental to both embryogenesis and tumor metastasis. The Notch intercellular signaling pathway regulates cell fate determination throughout metazoan evolution, and overexpression of activating alleles is oncogenic in mammals. Here we demonstrate that Notch activity promotes EMT during both cardiac development and oncogenic transformation via transcriptional induction of the Snail repressor, a potent and evolutionarily conserved mediator of EMT in many tissues and tumor types. In the embryonic heart, Notch functions via lateral induction to promote a selective transforming growth factor-β (TGFβ)-mediated EMT that leads to cellularization of developing cardiac valvular primordia. Embryos that lack Notch signaling elements exhibit severely attenuated cardiac snail expression, abnormal maintenance of intercellular endocardial adhesion complexes, and abortive endocardial EMT in vivo and in vitro. Accordingly, transient ectopic expression of activated Notch1 (N1IC) in zebrafish embryos leads to hypercellular cardiac valves, whereas Notch inhibition prevents valve development. Overexpression of N1IC in immortalized endothelial cells in vitro induces EMT accompanied by oncogenic transformation, with corresponding induction of snail and repression of VE-cadherin expression. Notch is expressed in embryonic regions where EMT occurs, suggesting an intimate and fundamental role for Notch, which may be reactivated during tumor metastasis. PMID:14701881

  12. The potent oncogene NPM-ALK mediates malignant transformation of normal human CD4(+) T lymphocytes.

    Science.gov (United States)

    Zhang, Qian; Wei, Fang; Wang, Hong Yi; Liu, Xiaobin; Roy, Darshan; Xiong, Qun-Bin; Jiang, Shuguang; Medvec, Andrew; Danet-Desnoyers, Gwenn; Watt, Christopher; Tomczak, Ewa; Kalos, Michael; Riley, James L; Wasik, Mariusz A

    2013-12-01

    With this study we have demonstrated that in vitro transduction of normal human CD4(+) T lymphocytes with NPM-ALK results in their malignant transformation. The transformed cells become immortalized and display morphology and immunophenotype characteristic of patient-derived anaplastic large-cell lymphomas. These unique features, which are strictly dependent on NPM-ALK activity and expression, include perpetual cell growth, proliferation, and survival; activation of the key signal transduction pathways STAT3 and mTORC1; and expression of CD30 (the hallmark of anaplastic large-cell lymphoma) and of immunosuppressive cytokine IL-10 and cell-surface protein PD-L1/CD274. Implantation of NPM-ALK-transformed CD4(+) T lymphocytes into immunodeficient mice resulted in formation of tumors indistinguishable from patients' anaplastic large-cell lymphomas. Our findings demonstrate that the key aspects of human carcinogenesis closely recapitulating the features of the native tumors can be faithfully reproduced in vitro when an appropriate oncogene is used to transform its natural target cells; this in turn points to the fundamental role in malignant cell transformation of potent oncogenes expressed in the relevant target cells. Such transformed cells should permit study of the early stages of carcinogenesis, and in particular the initial oncogene-host cell interactions. This experimental design could also be useful for studies of the effects of early therapeutic intervention and likely also the mechanisms of malignant progression.

  13. Narrowing the focus: a toolkit to systematically connect oncogenic signaling pathways with cancer phenotypes

    Science.gov (United States)

    Singleton, Katherine R.; Wood, Kris C.

    2016-01-01

    Functional genomics approaches such as gain- and loss-of-function screening can efficiently reveal genes that control cancer cell growth, survival, signal transduction, and drug resistance, but distilling the results of large-scale screens into actionable therapeutic strategies is challenging given our incomplete understanding of the functions of many genes. Research over several decades, including the results of large-scale cancer sequencing projects, has made it clear that many oncogenic properties are controlled by a common set of core oncogenic signaling pathways. By directly screening this core set of pathways, rather than much larger numbers of individual genes, it may be possible to more directly and efficiently connect functional genomic screening results with therapeutic targets. Here, we describe the recent development of methods to directly screen oncogenic pathways in high-throughput. We summarize the results of studies that have used pathway-centric screening to map the pathways of resistance to targeted therapies in diverse cancer types, then conclude by expanding on potential future applications of this approach.

  14. Determination of somatic oncogenic mutations linked to target-based therapies using MassARRAY technology

    Science.gov (United States)

    Llorca-Cardeñosa, Marta J.; Mongort, Cristina; Alonso, Elisa; Navarro, Samuel; Burgues, Octavio; Vivancos, Ana; Cejalvo, Juan Miguel; Perez-Fidalgo, José Alejandro; Roselló, Susana; Ribas, Gloria; Cervantes, Andrés

    2016-01-01

    Somatic mutation analysis represents a useful tool in selecting personalized therapy. The aim of our study was to determine the presence of common genetic events affecting actionable oncogenes using a MassARRAY technology in patients with advanced solid tumors who were potential candidates for target-based therapies. The analysis of 238 mutations across 19 oncogenes was performed in 197 formalin-fixed paraffin-embedded samples of different tumors using the OncoCarta Panel v1.0 (Sequenom Hamburg, Germany). Of the 197 specimens, 97 (49.2%) presented at least one mutation. Forty-nine different oncogenic mutations in 16 genes were detected. Mutations in KRAS and PIK3CA were detected in 40/97 (41.2%) and 30/97 (30.9%) patients respectively. Thirty-one patients (32.0%) had mutations in two genes, 20 of them (64.5%) initially diagnosed with colorectal cancer. The co-occurrence of mutation involved mainly KRAS, PIK3CA, KIT and RET. Mutation profiles were validated using a customized panel and the Junior Next-Generation Sequencing technology (GS-Junior 454, Roche). Twenty-eight patients participated in early clinical trials or received specific treatments according to the molecular characterization (28.0%). MassARRAY technology is a rapid and effective method for identifying key cancer-driving mutations across a large number of samples, which allows for a more appropriate selection for personalized therapies. PMID:26968814

  15. HER2 missense mutations have distinct effects on oncogenic signaling and migration.

    Science.gov (United States)

    Zabransky, Daniel J; Yankaskas, Christopher L; Cochran, Rory L; Wong, Hong Yuen; Croessmann, Sarah; Chu, David; Kavuri, Shyam M; Red Brewer, Monica; Rosen, D Marc; Dalton, W Brian; Cimino-Mathews, Ashley; Cravero, Karen; Button, Berry; Kyker-Snowman, Kelly; Cidado, Justin; Erlanger, Bracha; Parsons, Heather A; Manto, Kristen M; Bose, Ron; Lauring, Josh; Arteaga, Carlos L; Konstantopoulos, Konstantinos; Park, Ben Ho

    2015-11-10

    Recurrent human epidermal growth factor receptor 2 (HER2) missense mutations have been reported in human cancers. These mutations occur primarily in the absence of HER2 gene amplification such that most HER2-mutant tumors are classified as "negative" by FISH or immunohistochemistry assays. It remains unclear whether nonamplified HER2 missense mutations are oncogenic and whether they are targets for HER2-directed therapies that are currently approved for the treatment of HER2 gene-amplified breast cancers. Here we functionally characterize HER2 kinase and extracellular domain mutations through gene editing of the endogenous loci in HER2 nonamplified human breast epithelial cells. In in vitro and in vivo assays, the majority of HER2 missense mutations do not impart detectable oncogenic changes. However, the HER2 V777L mutation increased biochemical pathway activation and, in the context of a PIK3CA mutation, enhanced migratory features in vitro. However, the V777L mutation did not alter in vivo tumorigenicity or sensitivity to HER2-directed therapies in proliferation assays. Our results suggest the oncogenicity and potential targeting of HER2 missense mutations should be considered in the context of cooperating genetic alterations and provide previously unidentified insights into functional analysis of HER2 mutations and strategies to target them.

  16. Depletion of insulin receptor substrate 2 reverses oncogenic transformation induced by v-src

    Institute of Scientific and Technical Information of China (English)

    Hong-zhi SUN; Lin XU; Bo ZHOU; Wei-jin ZANG; Shu-fang WU

    2011-01-01

    Aim: To investigate the role of insulin receptor substrate 2 (IRS-2) in oncogenic transformation induced by v-src. Methods: IRS-2 gene was silenced using small interfering RNAs (siRNAs). Nuclear translocation and interaction of IRS-2 with v-src was determined using subcellular fractionation, confocal microscopy, and immunoprecipitation. The activity of the cyclin D1 promoter and r-DNA promoter was measured with a luciferase assay.Results: Depletion of IRS-2 inhibited R-/v-src cell growth and reverse the oncogenic transformation. IRS-2 bound to src via its two PI3-K binding sites, which are critical for activities involved in the transformation. Nuclear IRS-2 occupied the cyclin D1 and rDNA promoters. The combination of IRS-2 and v-src increased the activity of the two promoters, especially the rDNA promoter.Conclusion: Depletion of insulin receptor substrate 2 could reverse oncogenic transformation induced by v-src.

  17. Oncogenic function and prognostic significance of protein tyrosine phosphatase PRL-1 in hepatocellular carcinoma.

    Science.gov (United States)

    Jin, Shaowen; Wang, Kaimei; Xu, Kang; Xu, Junyao; Sun, Jian; Chu, Zhonghua; Lin, Dechen; Koeffler, Phillip H; Wang, Jie; Yin, Dong

    2014-06-15

    Our SNP-Chip data demonstrated 7/60 (12%) hepatocellular carcinoma (HCC) patients had PRL-1 copy number amplification. However, its biological functions and signaling pathways in HCC are deficient. Here, we investigated its oncogenic function and prognostic significance in HCC. PRL-1 protein levels were examined in 167 HCC samples by immunohistochemisty (IHC). The relationship of PRL-1 expression and clinicopathological features was assessed by correlation, Kaplan-Meier and Cox regression analyses. The oncogenic function of PRL-1 in HCC cells and its underlying mechanism were investigated by ectopic overexpression and knockdown model. PRL-1 levels in primary HCC and metastatic intravascular cancer thrombus were also determined by IHC. PRL-1 levels were frequently elevated in HCC tissues (81%), and elevated expression of PRL-1 was significantly associated with more aggressive phenotype and poorer prognosis in HCC patients (pPRL-1 markedly enhanced HCC cells migration and invasion. Furthermore, the oncogenic functions of PRL-1 were mediated by PI3K/AKT/GSK3β signaling pathway through inhibiting E-cadherin expression. Finally, PRL-1 protein levels in metastatic cancer thrombus were higher than that in primary HCC tissues (pPRL-1 in HCC invasion and metastasis implicating PRL-1 as a potential prognostic marker as well as therapeutic target in HCC.

  18. A posttranslational modification cascade involving p38, Tip60, and PRAK mediates oncogene-induced senescence.

    Science.gov (United States)

    Zheng, Hui; Seit-Nebi, Alim; Han, Xuemei; Aslanian, Aaron; Tat, John; Liao, Rong; Yates, John R; Sun, Peiqing

    2013-06-06

    Oncogene-induced senescence is an important tumor-suppressing defense mechanism. However, relatively little is known about the signaling pathway mediating the senescence response. Here, we demonstrate that a multifunctional acetyltransferase, Tip60, plays an essential role in oncogenic ras-induced senescence. Further investigation reveals a cascade of posttranslational modifications involving p38, Tip60, and PRAK, three proteins that are essential for ras-induced senescence. Upon activation by ras, p38 induces the acetyltransferase activity of Tip60 through phosphorylation of Thr158; activated Tip60 in turn directly interacts with and induces the protein kinase activity of PRAK through acetylation of K364 in a manner that depends on phosphorylation of both Tip60 and PRAK by p38. These posttranslational modifications are critical for the prosenescent function of Tip60 and PRAK, respectively. These results have defined a signaling pathway that mediates oncogene-induced senescence, and identified posttranslational modifications that regulate the enzymatic activity and biological functions of Tip60 and PRAK.

  19. Beneficial effects of low dose radiation in response to the oncogenic KRAS induced cellular transformation.

    Science.gov (United States)

    Kim, Rae-Kwon; Kim, Min-Jung; Seong, Ki Moon; Kaushik, Neha; Suh, Yongjoon; Yoo, Ki-Chun; Cui, Yan-Hong; Jin, Young Woo; Nam, Seon Young; Lee, Su-Jae

    2015-10-30

    Recently low dose irradiation has gained attention in the field of radiotherapy. For lack of understanding of the molecular consequences of low dose irradiation, there is much doubt concerning its risks on human beings. In this article, we report that low dose irradiation is capable of blocking the oncogenic KRAS-induced malignant transformation. To address this hypothesis, we showed that low dose irradiation, at doses of 0.1 Gray (Gy); predominantly provide defensive response against oncogenic KRAS -induced malignant transformation in human cells through the induction of antioxidants without causing cell death and acts as a critical regulator for the attenuation of reactive oxygen species (ROS). Importantly, we elucidated that knockdown of antioxidants significantly enhanced ROS generation, invasive and migratory properties and abnormal acini formation in KRAS transformed normal as well as cancer cells. Taken together, this study demonstrates that low dose irradiation reduces the KRAS induced malignant cellular transformation through diminution of ROS. This interesting phenomenon illuminates the beneficial effects of low dose irradiation, suggesting one of contributory mechanisms for reducing the oncogene induced carcinogenesis that intensify the potential use of low dose irradiation as a standard regimen.

  20. Emerging Roles of Agrobacterial Plant-Transforming Oncogenes in Plant Defense Reactions

    Science.gov (United States)

    Bulgakov, Victor P.; Inyushkina, Yuliya V.; Gorpenchenko, Tatiana Y.; Koren, Olga G.; Shkryl, Yuri N.; Zhuravlev, Yuri N.

    2009-01-01

    For recent years, engineering plant metabolic pathways by using rol genes looks promising in several aspects. New directions of rol-gene studies are highlighted in this work underlying the unique regulatory properties of the genes. It is known that following agrobacterial infection, the Agrobacterium rhizogenes rolA, rolB and rolC genes are transferred to plant genome, causing tumor formation and hairy root disease. In this report, we show mat these oncogenes are also involved in regulation of plant defense reactions, including the production of secondary metabolites. Situations occur where the rol genes perform their own critical function to regulate secondary metabolism by bypassing upstream plant control mechanisms and directing defense reactions via a "short cut." The rolC gene expressed in transformed plant cells is efficient in establishing an enhanced resistance of host cells to salt and temperature stresses. The emerging complexity of the rol-gene triggered effects and the involvement of signals generated by these genes in basic processes of cell biology such as calcium and ROS signaling indicate that the plant oncogenes, like some animal protooncogenes, use sophisticated strategies to affect cell growth and differentiation. The data raise the intriguing possibility that some components of plant and animal oncogene signaling pathways share common features.

  1. Gene expression array analyses predict increased proto-oncogene expression in MMTV induced mammary tumors.

    Science.gov (United States)

    Popken-Harris, Pamela; Kirchhof, Nicole; Harrison, Ben; Harris, Lester F

    2006-08-01

    Exogenous infection by milk-borne mouse mammary tumor viruses (MMTV) typically induce mouse mammary tumors in genetically susceptible mice at a rate of 90-95% by 1 year of age. In contrast to other transforming retroviruses, MMTV acts as an insertional mutagen and under the influence of steroid hormones induces oncogenic transformation after insertion into the host genome. As these events correspond with increases in adjacent proto-oncogene transcription, we used expression array profiling to determine which commonly associated MMTV insertion site proto-oncogenes were transcriptionally active in MMTV induced mouse mammary tumors. To verify our gene expression array results we developed real-time quantitative RT-PCR assays for the common MMTV insertion site genes found in RIII/Sa mice (int-1/wnt-1, int-2/fgf-3, int-3/Notch 4, and fgf8/AIGF) as well as two genes that were consistently up regulated (CCND1, and MAT-8) and two genes that were consistently down regulated (FN1 and MAT-8) in the MMTV induced tumors as compared to normal mammary gland. Finally, each tumor was also examined histopathologically. Our expression array findings support a model whereby just one or a few common MMTV insertions into the host genome sets up a dominant cascade of events that leave a characteristic molecular signature.

  2. Control of gene expression during T cell activation: alternate regulation of mRNA transcription and mRNA stability

    Directory of Open Access Journals (Sweden)

    Gorospe Myriam

    2005-05-01

    Full Text Available Abstract Background Microarray technology has become highly valuable for identifying complex global changes in gene expression patterns. The effective correlation of observed changes in gene expression with shared transcription regulatory elements remains difficult to demonstrate convincingly. One reason for this difficulty may result from the intricate convergence of both transcriptional and mRNA turnover events which, together, directly influence steady-state mRNA levels. Results In order to investigate the relative contribution of gene transcription and changes in mRNA stability regulation to standard analyses of gene expression, we used two distinct microarray methods which individually measure nuclear gene transcription and changes in polyA mRNA gene expression. Gene expression profiles were obtained from both polyA mRNA (whole-cell and nuclear run-on (newly transcribed RNA across a time course of one hour following the activation of human Jurkat T cells with PMA plus ionomycin. Comparative analysis revealed that regulation of mRNA stability may account for as much as 50% of all measurements of changes in polyA mRNA in this system, as inferred by the absence of any corresponding regulation of nuclear gene transcription activity for these groups of genes. Genes which displayed dramatic elevations in both mRNA and nuclear run-on RNA were shown to be inhibited by Actinomycin D (ActD pre-treatment of cells while large numbers of genes regulated only through altered mRNA turnover (both up and down were ActD-resistant. Consistent patterns across the time course were observed for both transcribed and stability-regulated genes. Conclusion We propose that regulation of mRNA stability contributes significantly to the observed changes in gene expression in response to external stimuli, as measured by high throughput systems.

  3. Protein phosphatase magnesium-dependent 1δ (PPM1D mRNA expression is a prognosis marker for hepatocellular carcinoma.

    Directory of Open Access Journals (Sweden)

    Guang-Bing Li

    Full Text Available BACKGROUND: Protein phosphatase magnesium-dependent 1δ (PPM1D is an oncogene, overexpressed in many solid tumors, including ovarian cancer and breast cancer. The current study examined the expression and the prognostic value of PPM1D mRNA in human hepatocellular carcinoma (HCC. METHODS: Total RNA was extracted from 86 HCC and paired non-cancerous liver tissues. PPM1D mRNA expression was determined by real-time quantitative reverse transcriptase-polymerase chain reaction (qPCR. Immunohistochemistry assay was used to verify the expression of ppm1d protein in the HCC and non-cancerous liver tissues. HCC patients were grouped according to PPM1D mRNA expression with the average PPM1D mRNA level in non-cancerous liver tissue samples as the cut-off. Correlations between clinicopathologic variables, overall survival and PPM1D mRNA expression were analyzed. FINDINGS: PPM1D mRNA was significantly higher in HCC than in the paired non-cancerous tissue (p<0.01. This was confirmed by ppm1d staining. 56 patients were classified as high expression group and the other 30 patients were categorized as low expression group. There were significant differences between the two groups in term of alpha-fetoprotein (α-FP level (p<0.01, tumor size (p<0.01, TNM stage (p<0.01, recurrence incidence (p<0.01 and family history of liver cancer (p<0.01. The current study failed to find significant differences between the two groups in the following clinical characteristics: age, gender, portal vein invasion, lymphnode metastasis, hepatitis B virus (HBV infection and alcohol intake. Survival time of high expression group was significantly shorter than that of low expression group (median survival, 13 months and 32 months, respectively, p<0.01. CONCLUSION: Up-regulation of PPM1D mRNA was associated with progressive pathological feature and poor prognosis in HCC patients. PPM1D mRNA may serve as a prognostic marker in HCC.

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

    Science.gov (United States)

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

  5. Effects of DNA replication on mRNA noise.

    Science.gov (United States)

    Peterson, Joseph R; Cole, John A; Fei, Jingyi; Ha, Taekjip; Luthey-Schulten, Zaida A

    2015-12-29

    There are several sources of fluctuations in gene expression. Here we study the effects of time-dependent DNA replication, itself a tightly controlled process, on noise in mRNA levels. Stochastic simulations of constitutive and regulated gene expression are used to analyze the time-averaged mean and variation in each case. The simulations demonstrate that to capture mRNA distributions correctly, chromosome replication must be realistically modeled. Slow relaxation of mRNA from the low copy number steady state before gene replication to the high steady state after replication is set by the transcript's half-life and contributes significantly to the shape of the mRNA distribution. Consequently both the intrinsic kinetics and the gene location play an important role in accounting for the mRNA average and variance. Exact analytic expressions for moments of the mRNA distributions that depend on the DNA copy number, gene location, cell doubling time, and the rates of transcription and degradation are derived for the case of constitutive expression and subsequently extended to provide approximate corrections for regulated expression and RNA polymerase variability. Comparisons of the simulated models and analytical expressions to experimentally measured mRNA distributions show that they better capture the physics of the system than previous theories.

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

    Science.gov (United States)

    Altamura, Gennaro; Corteggio, Annunziata; Pacini, Laura; Conte, Andrea; Pierantoni, Giovanna Maria; Tommasino, Massimo; Accardi, Rosita; Borzacchiello, Giuseppe

    2016-09-01

    Felis catus papillomavirus type 2 (FcaPV2) DNA is found in feline cutaneous squamous cell carcinomas (SCCs); however, its biological properties are still uncharacterized. In this study, we successfully expressed FcaPV2 E6 and E7 putative oncogenes in feline epithelial cells and demonstrated that FcaPV2 E6 binds to p53, impairing its protein level. In addition, E6 and E7 inhibited ultraviolet B (UVB)-triggered accumulation of p53, p21 and pro-apoptotic markers such as Cleaved Caspase3, Bax and Bak, suggesting a synergistic action of the virus with UV exposure in tumour pathogenesis. Furthermore, FcaPV2 E7 bound to feline pRb and impaired pRb levels, resulting in upregulation of the downstream pro-proliferative genes Cyclin A and Cdc2. Importantly, we demonstrated mRNA expression of FcaPV2 E2, E6 and E7 in feline SCC samples, strengthening the hypothesis of a causative role in the development of feline SCC. Copyright © 2016 Elsevier Inc. All rights reserved.

  7. Acidosis decreases c-Myc oncogene expression in human lymphoma cells: a role for the proton-sensing G protein-coupled receptor TDAG8.

    Science.gov (United States)

    Li, Zhigang; Dong, Lixue; Dean, Eric; Yang, Li V

    2013-10-11

    Acidosis is a biochemical hallmark of the tumor microenvironment. Here, we report that acute acidosis decreases c-Myc oncogene expression in U937 human lymphoma cells. The level of c-Myc transcripts, but not mRNA or protein stability, contributes to c-Myc protein reduction under acidosis. The pH-sensing receptor TDAG8 (GPR65) is involved in acidosis-induced c-Myc downregulation. TDAG8 is expressed in U937 lymphoma cells, and the overexpression or knockdown of TDAG8 further decreases or partially rescues c-Myc expression, respectively. Acidic pH alone is insufficient to reduce c-Myc expression, as it does not decrease c-Myc in H1299 lung cancer cells expressing very low levels of pH-sensing G protein-coupled receptors (GPCRs). Instead, c-Myc is slightly increased by acidosis in H1299 cells, but this increase is completely inhibited by ectopic overexpression of TDAG8. Interestingly, TDAG8 expression is decreased by more than 50% in human lymphoma samples in comparison to non-tumorous lymph nodes and spleens, suggesting a potential tumor suppressor function of TDAG8 in lymphoma. Collectively, our results identify a novel mechanism of c-Myc regulation by acidosis in the tumor microenvironment and indicate that modulation of TDAG8 and related pH-sensing receptor pathways may be exploited as a new approach to inhibit Myc expression.

  8. Acidosis Decreases c-Myc Oncogene Expression in Human Lymphoma Cells: A Role for the Proton-Sensing G Protein-Coupled Receptor TDAG8

    Directory of Open Access Journals (Sweden)

    Zhigang Li

    2013-10-01

    Full Text Available Acidosis is a biochemical hallmark of the tumor microenvironment. Here, we report that acute acidosis decreases c-Myc oncogene expression in U937 human lymphoma cells. The level of c-Myc transcripts, but not mRNA or protein stability, contributes to c-Myc protein reduction under acidosis. The pH-sensing receptor TDAG8 (GPR65 is involved in acidosis-induced c-Myc downregulation. TDAG8 is expressed in U937 lymphoma cells, and the overexpression or knockdown of TDAG8 further decreases or partially rescues c-Myc expression, respectively. Acidic pH alone is insufficient to reduce c-Myc expression, as it does not decrease c-Myc in H1299 lung cancer cells expressing very low levels of pH-sensing G protein-coupled receptors (GPCRs. Instead, c-Myc is slightly increased by acidosis in H1299 cells, but this increase is completely inhibited by ectopic overexpression of TDAG8. Interestingly, TDAG8 expression is decreased by more than 50% in human lymphoma samples in comparison to non-tumorous lymph nodes and spleens, suggesting a potential tumor suppressor function of TDAG8 in lymphoma. Collectively, our results identify a novel mechanism of c-Myc regulation by acidosis in the tumor microenvironment and indicate that modulation of TDAG8 and related pH-sensing receptor pathways may be exploited as a new approach to inhibit Myc expression.

  9. mTORC1 upregulation via ERK-dependent gene expression change confers intrinsic resistance to MEK inhibitors in oncogenic KRas-mutant cancer cells.

    Science.gov (United States)

    Komatsu, N; Fujita, Y; Matsuda, M; Aoki, K

    2015-11-05

    Cancer cells harboring oncogenic BRaf mutants, but not oncogenic KRas mutants, are sensitive to MEK inhibitors (MEKi). The mechanism underlying the intrinsic resistance to MEKi in KRas-mutant cells is under intensive investigation. Here, we pursued this mechanism by live imaging of extracellular signal-regulated kinases (ERK) and mammalian target of rapamycin complex 1 (mTORC1) activities in oncogenic KRas or BRaf-mutant cancer cells. We established eight cancer cell lines expressing Förster resonance energy transfer (FRET) biosensors for ERK activity and S6K activity, which was used as a surrogate marker for mTORC1 activity. Under increasing concentrations of MEKi, ERK activity correlated linearly with the cell growth rate in BRaf-mutant cancer cells, but not KRas-mutant cancer cells. The administration of PI3K inhibitors resulted in a linear correlation between ERK activity and cell growth rate in KRas-mutant cancer cells. Intriguingly, mTORC1 activity was correlated linearly with the cell growth rate in both BRaf-mutant cancer cells and KRas-mutant cancer cells. These observations suggested that mTORC1 activity had a pivotal role in cell growth and that the mTORC1 activity was maintained primarily by the ERK pathway in BRaf-mutant cancer cells and by both the ERK and PI3K pathways in KRas-mutant cancer cells. FRET imaging revealed that MEKi inhibited mTORC1 activity with slow kinetics, implying transcriptional control of mTORC1 activity by ERK. In agreement with this observation, MEKi induced the expression of negative regulators of mTORC1, including TSC1, TSC2 and Deptor, which occurred more significantly in BRaf-mutant cells than in KRas-mutant cells. These findings suggested that the suppression of mTORC1 activity and induction of negative regulators of mTORC1 in cancer cells treated for at least 1 day could be used as surrogate markers for the MEKi sensitivity of cancer cells.

  10. Oncogenic EGFR Represses the TET1 DNA Demethylase to Induce Silencing of Tumor Suppressors in Cancer Cells

    Directory of Open Access Journals (Sweden)

    Matteo Forloni

    2016-07-01

    Full Text Available Oncogene-induced DNA methylation-mediated transcriptional silencing of tumor suppressors frequently occurs in cancer, but the mechanism and functional role of this silencing in oncogenesis are not fully understood. Here, we show that oncogenic epidermal growth factor receptor (EGFR induces silencing of multiple unrelated tumor suppressors in lung adenocarcinomas and glioblastomas by inhibiting the DNA demethylase TET oncogene family member 1 (TET1 via the C/EBPα transcription factor. After oncogenic EGFR inhibition, TET1 binds to tumor suppressor promoters and induces their re-expression through active DNA demethylation. Ectopic expression of TET1 potently inhibits lung and glioblastoma tumor growth, and TET1 knockdown confers resistance to EGFR inhibitors in lung cancer cells. Lung cancer samples exhibited reduced TET1 expression or TET1 cytoplasmic localization in the majority of cases. Collectively, these results identify a conserved pathway of oncogenic EGFR-induced DNA methylation-mediated transcriptional silencing of tumor suppressors that may have therapeutic benefits for oncogenic EGFR-mediated lung cancers and glioblastomas.

  11. mRNA trafficking and local translation: the Yin and Yang of regulating mRNA localization in neurons

    Institute of Scientific and Technical Information of China (English)

    John R. Sinnamon; Kevin Czaplinski

    2011-01-01

    Localized translation and the requisite trafficking of the mRNA template play significant roles in the nervous system including the establishment of dendrites and axons,axon path-finding,and synaptic plasticity.We provide a brief review on the regulation of localizing mRNA in mammalian neurons through critical posttranslational modifications of the factors involved.These examples highlight the relationship between mRNA trafficking and the translational regulation of trafficked mRNAs and provide insight into how extracellular signals target these events during signal transduction.

  12. Chrysotile effects on the expression of anti-oncogene P53 and P16 and oncogene C-jun and C-fos in Wistar rats' lung tissues.

    Science.gov (United States)

    Cui, Yan; Wang, Yuchan; Deng, Jianjun; Hu, Gongli; Dong, Faqin; Zhang, Qingbi

    2017-09-13

    Chrysotile is the most widely used form of asbestos worldwide. China is the world's largest consumer and second largest producer of chrysotile. The carcinogenicity of chrysotile has been extensively documented, and accumulative evidence has shown that chrysotile is capable of causing lung cancer and other forms of cancer. However, molecular mechanisms underlying the tumorigenic effects of chrysotile remained poorly understood. To explore the carcinogenicity of chrysotile, Wistar rats were administered by intratracheal instillation (by an artificial route of administration) for 0, 0.5, 2, or 8 mg/ml of natural chrysotile (from Mangnai, Qinghai, China) dissolved in saline, repeated once a month for 6 months (a repeated high-dose exposure which may have little bearing on the effects following human exposure). The lung tissues were analyzed for viscera coefficients and histopathological alterations. Expression of P53, P16, C-JUN, and C-FOS was measured by western blotting and qRT-PCR. Our results found that chrysotile exposure leads the body weight to grow slowly and lung viscera coefficients to increase in a dose-dependent manner. General sample showed white nodules, punctiform asbestos spots, and irregular atrophy; moreover, HE staining revealed inflammatory infiltration, damage of alveolar structures, agglomerations, and pulmonary fibrosis. In addition, chrysotile can induce inactivation of the anti-oncogene P53 and P16 and activation of the proto-oncogenes C-JUN and C-FOS both in the messenger RNA and protein level. In conclusion, chrysotile induced an imbalanced expression of cancer-related genes in rats' lung tissue. These results contribute to our understanding of the carcinogenic mechanism of chrysotile.

  13. Increased IL-10 mRNA and IL-23 mRNA expression in multiple sclerosis: interferon-beta treatment increases IL-10 mRNA expression while reducing IL-23 mRNA expression

    DEFF Research Database (Denmark)

    Krakauer, M.; Sorensen, P.; Khademi, M.

    2008-01-01

    of the regulatory cytokine IL-10. The elevated IL-23 mRNA levels in MS patients are noteworthy in view of the newly discovered IL-23-driven Th17 T-cell subset, which is crucial in animal models of MS. Since IFN-beta therapy resulted in decreased IL-23 mRNA levels, the Th17 axis could be another target of IFN...

  14. Molecular Cloning of a Novel Mouse Testis-specific Spermatogenic Cell Apoptosis Inhibitor Gene mTSARG7 as a Candidate Oncogene

    Institute of Scientific and Technical Information of China (English)

    Xiao-Jun TAN; Guang-Xiu LU; Xiao-Wei XING; Lu-Yun LI; Zhao-Di WU; Chang-Gao ZHONG; Dong-Song NIE; Jun-Jiang FU; Yang XIANG; Yun DENG

    2005-01-01

    A novel mouse gene, mTSARG7 (GenBank accession No. AY489184), with a full cDNA length of 2279 bp and containing 12 exons and 11 introns, was cloned from a mouse expressed sequence tag (GenBank accession No. BE644543) that was significantly up-regulated in cryptorchidism. The gene was located in mouse chromosome 8A1.3 and encoded a protein containing 403 amino acid residues that was a new member of the acyltransferase family because the sequence contained the highly conserved phosphate acyltransferase (PlsC) domain existing in all acyltransferase-like proteins. The mTSARG7 protein and AU041707protein shared 83.9% identity in 402 amino acid residues. Expression of the mTSARG7 gene was restricted to the mouse testis. The results of the in situ hybridization analysis revealed that the mTSARG7 mRNA was expressed in mouse spermatogonia and spermatocytes. Subcellular localization studies showed that the EGFPtagged mTSARG7 protein was localized in the cytoplasm of GC-1 spg cells. The mTSARG7 mRNA expression was initiated in the mouse testis in the second week after birth, and the expression level increased steadily with spermatogenesis and sexual maturation of the mouse. The results of the heat stress experiment showed that the mTSARG7 mRNA expression gradually decreased as the heating duration increased. The pcDNA3.1 Hygro(-)/mTSARG7 plasmid was constructed and introduced into GC-1 spg cells by liposome transfection. The mTSARG7 can accelerate GC-1 spg cells, causing them to traverse the S-phase and enter the G2-phase, compared with the control group where this did not occur as there was no transfection of mTSARG7. In conclusion, our results suggest that this gene may play an important role in spermatogenesis and the development of cryptorchid testes, and is a testis-specific apoptosis candidate oncogene.

  15. Radiolabeled oligonucleotides for antisense imaging

    Science.gov (United States)

    Iyer, Arun K; He, Jiang

    2011-01-01

    Oligonucleotides radiolabeled with isotopes emitting γ-rays (for SPECT imaging) or positrons (for PET imaging) can be useful for targeting messenger RNA (mRNA) thereby serving as non-invasive imaging tools for detection of gene expression in vivo (antisense imaging). Radiolabeled oligonucleotides may also be used for monitoring their in vivo fate, thereby helping us better understand the barriers to its delivery for antisense targeting. These developments have led to a new area of molecular imaging and targeting, utilizing radiolabeled antisense oligonucleotides. However, the success of antisense imaging relies heavily on overcoming the barriers for its targeted delivery in vivo. Furthermore, the low ability of the radiolabeled antisense oligonucleotide to subsequently internalize into the cell and hybridize with its target mRNA poses additional challenges in realizing its potentials. This review covers the advances in the antisense imaging probe development for PET and SPECT, with an emphasis on radiolabeling strategies, stability, delivery and in vivo targeting. PMID:21822406

  16. Dynamics of Translation of Single mRNA Molecules In Vivo.

    Science.gov (United States)

    Yan, Xiaowei; Hoek, Tim A; Vale, Ronald D; Tanenbaum, Marvin E

    2016-05-05

    Regulation of mRNA translation, the process by which ribosomes decode mRNAs into polypeptides, is used to tune cellular protein levels. Currently, methods for observing the complete process of translation from single mRNAs in vivo are unavailable. Here, we report the long-term (>1 hr) imaging of single mRNAs undergoing hundreds of rounds of translation in live cells, enabling quantitative measurements of ribosome initiation, elongation, and stalling. This approach reveals a surprising heterogeneity in the translation of individual mRNAs within the same cell, including rapid and reversible transitions between a translating and non-translating state. Applying this method to the cell-cycle gene Emi1, we find strong overall repression of translation initiation by specific 5' UTR sequences, but individual mRNA molecules in the same cell can exhibit dramatically different translational efficiencies. The ability to observe translation of single mRNA molecules in live cells provides a powerful tool to study translation regulation.

  17. The in vitro effect of desflurane preconditioning on endothelial adhesion molecules and mRNA expression.

    Science.gov (United States)

    Biao, Zhu; Zhanggang, Xue; Hao, Jiang; Changhong, Miao; Jing, Cang

    2005-04-01

    Lower expression of intercellular adhesion molecule-1 (ICAM-1), vascular adhesion molecule-1 (VCAM-1), and E-selectin may be responsible for attenuated ischemic-reperfusion neutrophil adhesion to vascular endothelium. Desflurane reduces ischemia-reperfusion injury. Therefore, we assessed whether desflurane affects the protein expression of ICAM-1 and E-selectin and mRNA expression of ICAM-1 and VCAM-1 of human umbilical venous endothelial cells (HUVEC) stimulated with tumor necrosis factor-alpha (TNF-alpha). HUVEC were preconditioned for 60 min with 1 minimum alveolar concentration desflurane before stimulating with TNF-alpha. Protein expression of adhesion molecules ICAM-1 and E-selectin of HUVEC were evaluated via immunocytochemical techniques combined with image cytometry. ICAM-1 and VCAM-1 mRNA expression of HUVEC were determined via reverse transcription-polymerase chain reaction. Desflurane not only reduced the protein expression of ICAM-1 and E-selectin but also ICAM-1 and VCAM-1 mRNA expression of the HUVEC. The adhesion rate of neutrophils with desflurane-treated HUVEC was slower. The decreased neutrophil adhesion on the desflurane-treated HUVEC correlated well with the decrease in adhesion molecule expression. These results show that desflurane affects the expression of adhesion molecules involved in the multistep process of neutrophil recruitment. Desflurane related ischemia-reperfusion injury reduction correlates well with expression inhibition of ICAM-1, VCAM-1, and E-selectin that mediates neutrophil rotation and firm adhesion on the vascular endothelium.

  18. The human papillomavirus E6 oncogene dysregulates the cell cycle and contributes to cervical carcinogenesis through two independent activities.

    Science.gov (United States)

    Shai, Anny; Brake, Tiffany; Somoza, Chamorro; Lambert, Paul F

    2007-02-15

    Cervical cancer is a leading cause of death due to cancer among women worldwide. Using transgenic mice to dissect the contributions of the human papillomavirus (HPV) 16 E6 and E7 oncogenes in cervical cancer, E7 was identified previously to be the dominant oncogene. Specifically, when treated with exogenous estrogen for 6 months, E7 transgenic mice developed cancer throughout the reproductive tract, but E6 transgenic mice did not. E6 contributed to carcinogenesis of the reproductive tract, as E6/E7 double transgenic mice treated for 6 months with estrogen developed larger cancers than E7 transgenic mice. In the current study, we investigated whether the E6 oncogene alone could cooperate with estrogen to induce cervical cancer after an extended estrogen treatment period of 9 months. We found that the E6 oncogene synergizes with estrogen to induce cervical cancer after 9 months, indicating that E6 has a weaker but detectable oncogenic potential in the reproductive tract compared with the E7 oncogene. Using transgenic mice that express mutant forms of HPV16 E6, we determined that the interactions of E6 with cellular alpha-helix and PDZ partners correlate with its ability to induce cervical carcinogenesis. In analyzing the tumors arising in E6 transgenic mice, we learned that E6 induces expression of the E2F-responsive genes, Mcm7 and cyclin E, in the absence of the E7 oncogene. E6 also prevented the expression of p16 in tumors of the reproductive tract through a mechanism mediated by the interaction of E6 with alpha-helix partners.

  19. Myc and Ras oncogenes engage different energy metabolism programs and evoke distinct patterns of oxidative and DNA replication stress.

    Science.gov (United States)

    Maya-Mendoza, Apolinar; Ostrakova, Jitka; Kosar, Martin; Hall, Arnaldur; Duskova, Pavlina; Mistrik, Martin; Merchut-Maya, Joanna Maria; Hodny, Zdenek; Bartkova, Jirina; Christensen, Claus; Bartek, Jiri

    2015-03-01

    Both Myc and Ras oncogenes impact cellular metabolism, deregulate redox homeostasis and trigger DNA replication stress (RS) that compromises genomic integrity. However, how are such oncogene-induced effects evoked and temporally related, to what extent are these kinetic parameters shared by Myc and Ras, and how are these cellular changes linked with oncogene-induced cellular senescence in different cell context(s) remain poorly understood. Here, we addressed the above-mentioned open questions by multifaceted comparative analyses of human cellular models with inducible expression of c-Myc and H-RasV12 (Ras), two commonly deregulated oncoproteins operating in a functionally connected signaling network. Our study of DNA replication parameters using the DNA fiber approach and time-course assessment of perturbations in glycolytic flux, oxygen consumption and production of reactive oxygen species (ROS) revealed the following results. First, overabundance of nuclear Myc triggered RS promptly, already after one day of Myc induction, causing slow replication fork progression and fork asymmetry, even before any metabolic changes occurred. In contrast, Ras overexpression initially induced a burst of cell proliferation and increased the speed of replication fork progression. However, after several days of induction Ras caused bioenergetic metabolic changes that correlated with slower DNA replication fork progression and the ensuing cell cycle arrest, gradually leading to senescence. Second, the observed oncogene-induced RS and metabolic alterations were cell-type/context dependent, as shown by comparative analyses of normal human BJ fibroblasts versus U2-OS sarcoma cells. Third, the energy metabolic reprogramming triggered by Ras was more robust compared to impact of Myc. Fourth, the detected oncogene-induced oxidative stress was due to ROS (superoxide) of non-mitochondrial origin and mitochondrial OXPHOS was reduced (Crabtree effect). Overall, our study provides novel

  20. Combining immunotherapy with oncogene-targeted therapy: a new road for melanoma treatment

    Directory of Open Access Journals (Sweden)

    Mariana eAris

    2015-02-01

    Full Text Available Cutaneous melanoma arises from the malignant transformation of skin melanocytes; its incidence and mortality have been increasing steadily over the last fifty-years, now representing 3% of total tumors. Once melanoma metastasizes, prognosis is somber and therapeutic options are limited. However, the discovery of prevalent BRAF mutations in at least 50% of melanoma tumors led to development of BRAF inhibitors, and other drugs targeting the MAPK pathway including MEK inhibitors, are changing this reality. These recently approved treatments for metastatic melanoma have made a significant impact on patient survival; though the results are shadowed by the appearance of drug-resistance. Combination therapies provide a rational strategy to potentiate efficacy and potentially overcome resistance. Undoubtedly, the last decade has also born an renaissance of immunotherapy, and encouraging advances in metastatic melanoma treatment are illuminating the road. Immune checkpoint blockades, such as CTLA-4 antagonist-antibodies, and multiple cancer vaccines are now invaluable arms of anti-tumor therapy. Recent work has brought to light the delicate relationship between tumor biology and the immune system. Host immunity contributes to the antitumor activity of oncogene-targeted inhibitors within a complex network of cytokines and chemokines. Therefore, combining immunotherapy with oncogene-targeted drugs may be the key to melanoma control. Here we review ongoing clinical studies of combination therapies using both oncogene inhibitors and immunotherapeutic strategies in melanoma patients. We will revisit the preclinical evidence that tested sequential and concurrent schemes in suitable animal models and formed the basis for the current trials. Finally, we will discuss potential future directions of the field.

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

    Energy Technology Data Exchange (ETDEWEB)

    Peña Avalos, B.L. de la

    2014-07-01

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

  2. The Plasticity of Oncogene Addiction: Implications for Targeted Therapies Directed to Receptor Tyrosine Kinases

    Directory of Open Access Journals (Sweden)

    Vinochani Pillay

    2009-05-01

    Full Text Available A common mutation of the epidermal growth factor receptor (EGFR in glioblastoma multiforme (GBM is an extracellular truncation known as the de2-7 EGFR (or EGFRvIII. Hepatocyte growth factor (HGF is the ligand for the receptor tyrosine kinase (RTK c-Met, and this signaling axis is often active in GBM. The expression of the HGF/c-Met axis or de2-7 EGFR independently enhances GBMgrowth and invasiveness, particularly through the phosphatidylinositol-3 kinase/pAkt pathway. Using RTK arrays, we show that expression of de2-7 EGFR in U87MG GBM cells leads to the coactivation of several RTKs, including platelet-derived growth factor receptor β and c-Met. A neutralizing antibody to HGF (AMG102 did not inhibit de2-7 EGFR-mediated activation of c-Met, demonstrating that it is ligand-independent. Therapy for parental U87MG xenografts with AMG 102 resulted in significant inhibition of tumor growth, whereas U87MG.Δ2-7 xenografts were profoundly resistant. Treatment of U87MG.Δ2-7 xenografts with panitumumab, an anti-EGFR antibody, only partially inhibited tumor growth as xenografts rapidly reverted to the HGF/c-Met signaling pathway. Cotreatment with panitumumab and AMG 102 prevented this escape leading to significant tumor inhibition through an apoptotic mechanism, consistent with the induction of oncogenic shock. This observation provides a rationale for using panitumumab and AMG 102 in combination for the treatment of GBM patients. These results illustrate that GBM cells can rapidly change the RTK driving their oncogene addiction if the alternate RTK signals through the same downstream pathway. Consequently, inhibition of a dominant oncogene by targeted therapy can alter the hierarchy of RTKs resulting in rapid therapeutic resistance.

  3. Microarray-based oncogenic pathway profiling in advanced serous papillary ovarian carcinoma.

    Directory of Open Access Journals (Sweden)

    Xuan Bich Trinh

    Full Text Available INTRODUCTION: The identification of specific targets for treatment of ovarian cancer patients remains a challenge. The objective of this study is the analysis of oncogenic pathways in ovarian cancer and their relation with clinical outcome. METHODOLOGY: A meta-analysis of 6 gene expression datasets was done for oncogenic pathway activation scores: AKT, β-Catenin, BRCA, E2F1, EGFR, ER, HER2, INFα, INFγ, MYC, p53, p63, PI3K, PR, RAS, SRC, STAT3, TNFα, and TGFβ and VEGF-A. Advanced serous papillary tumours from uniformly treated patients were selected (N = 464 to find differences independent from stage-, histology- and treatment biases. Survival and correlations with documented prognostic signatures (wound healing response signature WHR/genomic grade index GGI/invasiveness gene signature IGS were analysed. RESULTS: The GGI, WHR, IGS score were unexpectedly increased in chemosensitive versus chemoresistant patients. PR and RAS activation score were associated with survival outcome (p = 0.002;p = 0.004. Increased activations of β-Catenin (p = 0.0009, E2F1 (p = 0.005, PI3K (p = 0.003 and p63 (p = 0.05 were associated with more favourable clinical outcome and were consistently correlated with three prognostic gene signatures. CONCLUSIONS: Oncogenic pathway profiling of advanced serous ovarian tumours revealed that increased β-Catenin, E2F1, p63, PI3K, PR and RAS-pathway activation scores were significantly associated with favourable clinical outcome. WHR, GGI and IGS scores were unexpectedly increased in chemosensitive tumours. Earlier studies have shown that WHR, GGI and IGS are strongly associated with proliferation and that high-proliferative ovarian tumours are more chemosensitive. These findings may indicate opposite confounding of prognostic versus predictive factors when studying biomarkers in epithelial ovarian cancer.

  4. G-rich proto-oncogenes are targeted for genomic instability in B-cell lymphomas.

    Science.gov (United States)

    Duquette, Michelle L; Huber, Michael D; Maizels, Nancy

    2007-03-15

    Diffuse large B-cell lymphoma is the most common lymphoid malignancy in adults. It is a heterogeneous disease with variability in outcome. Genomic instability of a subset of proto-oncogenes, including c-MYC, BCL6, RhoH, PIM1, and PAX5, can contribute to initial tumor development and has been correlated with poor prognosis and aggressive tumor growth. Lymphomas in which these proto-oncogenes are unstable derive from germinal center B cells that express activation-induced deaminase (AID), the B-cell-specific factor that deaminates DNA to initiate immunoglobulin gene diversification. Proto-oncogene instability is evident as both aberrant hypermutation and translocation, paralleling programmed instability which diversifies the immunoglobulin loci. We have asked if genomic sequence correlates with instability in AID-positive B-cell lymphomas. We show that instability does not correlate with enrichment of the WRC sequence motif that is the consensus for deamination by AID. Instability does correlate with G-richness, evident as multiple runs of the base guanine on the nontemplate DNA strand. Extending previous analysis of c-MYC, we show experimentally that transcription of BCL6 and RhoH induces formation of structures, G-loops, which contain single-stranded regions targeted by AID. We further show that G-richness does not characterize translocation breakpoints in AID-negative B- and T-cell malignancies. These results identify G-richness as one feature of genomic structure that can contribute to genomic instability in AID-positive B-cell malignancies.

  5. HPV E6/E7 mRNA versus HPV DNA biomarker in cervical cancer screening of a group of Macedonian women.

    Science.gov (United States)

    Duvlis, Sotirija; Popovska-Jankovic, Katerina; Arsova, Zorica Sarafinovska; Memeti, Shaban; Popeska, Zaneta; Plaseska-Karanfilska, Dijana

    2015-09-01

    High risk types of human papillomaviruses E6/E7 oncogenes and their association with tumor suppressor genes products are the key factors of cervical carcinogenesis. This study proposed them as specific markers for cervical dysplasia screening. The aim of the study is to compare the clinical and prognostic significance of HPV E6/E7 mRNA as an early biomarker versus HPV DNA detection and cytology in triage of woman for cervical cancer. The study group consists of 413 women: 258 NILM, 26 ASC-US, 81 LSIL, 41 HSIL, and 7 unsatisfactory cytology. HPV4AACE screening, real-time multiplex PCR and MY09/11 consensus PCR primers methods were used for the HPV DNA detection. The real-time multiplex nucleic acid sequence-based assay (NucliSENS EasyQ HPV assay) was used for HPV E6/E7 mRNA detection of the five most common high risk HPV types in cervical cancer (16, 18, 31, 33, and 45). The results show that HPV E6/E7 mRNA testing had a higher specificity 50% (95% CI 32-67) and positive predictive value (PPV) 62% (95% CI 46-76) for CIN2+ compared to HPV DNA testing that had specificity of 18% (95% CI 7-37) and PPV 52% (95% CI 39-76) respectively. The higher specificity and PPV of HPV E6/E7 mRNA testing are valuable in predicting insignificant HPV DNA infection among cases with borderline cytological finding. It can help in avoiding aggressive procedures (biopsies and over-referral of transient HPV infections) as well as lowering patient's anxiety and follow up period. © 2015 Wiley Periodicals, Inc.

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

    Science.gov (United States)

    2015-10-01

    Oncogenic Pathway in Castration Resistance and Chemoresistance of Prostate Cancer 3 Annual Progress Report W81XWH-13-1-0162 Using a Novel...Transgenic Mouse Model to Study c-Myc Oncogenic Pathway in Castration Resistance and Chemoresistance of Prostate Cancer Feng Yang, Ph.D. Department of...AWARD NUMBER: W81XWH-13-1-0162 TITLE: Using a Novel Transgenic Mouse Model to Study c-Myc Oncogenic Pathway in Castration Resistance and

  7. Kaposi Sarcoma of Childhood: Inborn or Acquired Immunodeficiency to Oncogenic HHV-8.

    Science.gov (United States)

    Jackson, Carolyn C; Dickson, Mark A; Sadjadi, Mahan; Gessain, Antoine; Abel, Laurent; Jouanguy, Emmanuelle; Casanova, Jean-Laurent

    2016-03-01

    Kaposi sarcoma (KS) is an endothelial malignancy caused by human herpes virus-8 (HHV-8) infection. The epidemic and iatrogenic forms of childhood KS result from a profound and acquired T cell deficiency. Recent studies have shown that classic KS of childhood can result from rare single-gene inborn errors of immunity, with mutations in WAS, IFNGR1, STIM1, and TNFRSF4. The pathogenesis of the endemic form of childhood KS has remained elusive. We review childhood KS pathogenesis and its relationship to inherited and acquired immunodeficiency to oncogenic HHV-8.

  8. Beyond an oncogene, Lin28 is a master regulator of cancer progression.

    Science.gov (United States)

    Wang, Xuefei; Weng, Mingjiao; Jin, Yinji; Yang, Weiwei; Wang, Xin; Wu, Di; Wang, Tianzhen; Li, Xiaobo

    2017-07-26

    The RNA binding protein Lin28 is increased in most human malignancies, and elevated Lin28 is a biomarker for poor prognosis and contributes to cancer progression. Lin28 functions as a master oncogene and is involved in almost all hallmarks of cancer. In this review, we summarize the aberrant molecular expression mechanisms and pathological roles of Lin28 in cancer progression. Moreover, we elaborate on the established molecular mechanisms, from the transcriptional level to the post-transcriptional and translational levels, by which Lin28 regulates cancer progression.

  9. Oncogenic mechanisms of Lin28 in breast cancer: new functions and therapeutic opportunities.

    Science.gov (United States)

    Xiong, Hanchu; Zhao, Wenhe; Wang, Ji; Seifer, Benjamin J; Ye, Chenyang; Chen, Yongxia; Jia, Yunlu; Chen, Cong; Shen, Jianguo; Wang, Linbo; Sui, Xinbing; Zhou, Jichun

    2017-04-11

    The RNA binding protein Lin28 is best known for the critical role in cell development, recent researches also have implied its oncogenic function in various human cancers, including breast cancer. Specifically, aberrant Lin28 participates in multiple pathological processes, such as proliferation, metastasis, radiotherapy and chemotherapy resistance, metabolism, immunity and inflammation as well as stemness. In this review, we summarize the let-7-dependent and let-7-independent mechanism regulated by Lin28, focusing on its relation with tumor hallmarks in breast cancer, and subsequently discuss our present knowledge of Lin28 to develop a molecular-based therapeutic strategy against breast cancer.

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

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    Mehtap Kilic Eren

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

  11. Oncogenic mutation profiling in new lung cancer and mesothelioma cell lines

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    Lam DC

    2015-01-01

    Full Text Available David CL Lam,1 Susan Y Luo,1 Wen Deng,2 Johnny SH Kwan,3 Jaime Rodriguez-Canales,4 Annie LM Cheung,5 Grace HW Cheng,6 Chi-Ho Lin,6 Ignacio I Wistuba,4 Pak C Sham,6 Thomas SK Wan,7 Sai-Wah Tsao5 1Department of Medicine, 2School of Nursing, 3Department of Psychiatry, University of Hong Kong, Hong Kong SAR, People’s Republic of China; 4Department of Translational Molecular Pathology, MD Anderson Cancer Center, University of Texas at Houston, Houston, TX, USA; 5Department of Anatomy, 6Center for Genome Sciences, 7Department of Pathology, University of Hong Kong, Hong Kong SAR, People’s Republic of China Background: Thoracic tumor, especially lung cancer, ranks as the top cancer mortality in most parts of the world. Lung adenocarcinoma is the predominant subtype and there is increasing knowledge on therapeutic molecular targets, namely EGFR, ALK, KRAS, and ROS1, among lung cancers. Lung cancer cell lines established with known clinical characteristics and molecular profiling of oncogenic targets like ALK or KRAS could be useful tools for understanding the biology of known molecular targets as well as for drug testing and screening. Materials and methods: Five new cancer cell lines were established from pleural fluid or biopsy tissues obtained from Chinese patients with primary lung adenocarcinomas or malignant pleural mesothelioma. They were characterized by immunohistochemistry, growth kinetics, tests for tumorigenicity, EGFR and KRAS gene mutations, ALK gene rearrangement and OncoSeq mutation profiling. Results: These newly established lung adenocarcinoma and mesothelioma cell lines were maintained for over 100 passages and demonstrated morphological and immunohistochemical features as well as growth kinetics of tumor cell lines. One of these new cell lines bears EML4-ALK rearrangement variant 2, two lung cancer cell lines bear different KRAS mutations at codon 12, and known single nucleotide polymorphism variants were identified in these cell

  12. Normal Expression of a Rearranged and Mutated c-myc Oncogene after Transfection into Fibroblasts

    Science.gov (United States)

    Richman, Adam; Hayday, Adrian

    1989-10-01

    Expression of the c-myc oncogene is deregulated in a variety of malignancies. Rearrangement and mutation of the c-myc locus is a characteristic feature of human Burkitt's lymphoma. Whether deregulation is solely a result of mutation of c-myc or whether it is influenced by the transformed B cell context has not been determined. A translocated and mutated allele of c-myc was stably transfected into fibroblasts. The rearranged allele was expressed indistinguishably from a normal c-myc gene: it had serum-regulated expression, was transcribed with normal promoter preference, and was strongly attenuated. Thus mutations by themselves are insufficient to deregulate c-myc transcription.

  13. BTB-Zinc Finger Oncogenes Are Required for Ras and Notch-Driven Tumorigenesis in Drosophila.

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    Karen Doggett

    Full Text Available During tumorigenesis, pathways that promote the epithelial-to-mesenchymal transition (EMT can both facilitate metastasis and endow tumor cells with cancer stem cell properties. To gain a greater understanding of how these properties are interlinked in cancers we used Drosophila epithelial tumor models, which are driven by orthologues of human oncogenes (activated alleles of Ras and Notch in cooperation with the loss of the cell polarity regulator, scribbled (scrib. Within these tumors, both invasive, mesenchymal-like cell morphology and continual tumor overgrowth, are dependent upon Jun N-terminal kinase (JNK activity. To identify JNK-dependent changes within the tumors we used a comparative microarray analysis to define a JNK gene signature common to both Ras and Notch-driven tumors. Amongst the JNK-dependent changes was a significant enrichment for BTB-Zinc Finger (ZF domain genes, including chronologically inappropriate morphogenesis (chinmo. chinmo was upregulated by JNK within the tumors, and overexpression of chinmo with either RasV12 or Nintra was sufficient to promote JNK-independent epithelial tumor formation in the eye/antennal disc, and, in cooperation with RasV12, promote tumor formation in the adult midgut epithelium. Chinmo primes cells for oncogene-mediated transformation through blocking differentiation in the eye disc, and promoting an escargot-expressing stem or enteroblast cell state in the adult midgut. BTB-ZF genes are also required for Ras and Notch-driven overgrowth of scrib mutant tissue, since, although loss of chinmo alone did not significantly impede tumor development, when loss of chinmo was combined with loss of a functionally related BTB-ZF gene, abrupt, tumor overgrowth was significantly reduced. abrupt is not a JNK-induced gene, however, Abrupt is present in JNK-positive tumor cells, consistent with a JNK-associated oncogenic role. As some mammalian BTB-ZF proteins are also highly oncogenic, our work suggests that

  14. Markers for sebaceoma show a spectrum of cell cycle regulators, tumor suppressor genes, and oncogenes

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    Ana Maria Abreu Velez

    2015-01-01

    Full Text Available Background: Sebaceoma is a tumor for which the causative oncogenes are not well-understood. Sebaceomas demonstrate some histopathologic features similar to basal cell carcinoma (BCC, such as palisading borders and basaloid cells with additional features, including foamy cytoplasm and indented nuclei. Aims: We examine multiple cell-cycle, oncogene, and tumor suppressor gene markers in sebaceomas, to try to find some suitable biological markers for this tumor, and compare with other published studies. Materials and Methods: We investigated a panel of immunohistochemical (IHC stains that are important for cellular signaling, including a cell cycle regulator, tumor suppressor gene, oncogene, hormone receptor, and genomic stability markers in our cohort of sebaceomas. We collected 30 sebaceomas from three separate USA dermatopathology laboratories. The following IHC panel: Epithelial membrane antigen (EMA/CD227, cytokeratin AE1/AE3, cyclin D1, human breast cancer 1 protein (BRCA-1, C-erb-2, Bcl-2, human androgen receptor (AR, cyclin-dependent kinase inhibitor 1B (p27 kip1 , p53, topoisomerase II alpha, proliferating cell nuclear antigen, and Ki-67 were tested in our cases. Results: EMA/CD227 was positive in the well-differentiated sebaceomas (13/30. Cyclin-dependent kinase inhibitor 1B was positive in tumors with intermediate differentiation (22/30. The less well-differentiated tumors failed to stain with EMA and AR. Most of the tumors with well-differentiated palisaded areas demonstrated positive staining for topoisomerase II alpha, p27 kip1 , and p53, with positive staining in tumoral basaloid areas (22/30. Numerous tumors were focally positive with multiple markers, indicating a significant degree of variability in the complete group. Conclusions: Oncogenes, tumor suppressor genes, cell cycle regulators, and hormone receptors are variably expressed in sebaceomas. Our results suggest that in these tumors, selected marker staining seems to correlate

  15. IMAGES, IMAGES, IMAGES

    Energy Technology Data Exchange (ETDEWEB)

    Marcus, A.

    1980-07-01

    The role of images of information (charts, diagrams, maps, and symbols) for effective presentation of facts and concepts is expanding dramatically because of advances in computer graphics technology, increasingly hetero-lingual, hetero-cultural world target populations of information providers, the urgent need to convey more efficiently vast amounts of information, the broadening population of (non-expert) computer users, the decrease of available time for reading texts and for decision making, and the general level of literacy. A coalition of visual performance experts, human engineering specialists, computer scientists, and graphic designers/artists is required to resolve human factors aspects of images of information. The need for, nature of, and benefits of interdisciplinary effort are discussed. The results of an interdisciplinary collaboration are demonstrated in a product for visualizing complex information about global energy interdependence. An invited panel will respond to the presentation.

  16. Identification of ALV-J associated acutely transforming virus Fu-J carrying complete v-fps oncogene.

    Science.gov (United States)

    Wang, Yixin; Li, Jianliang; Li, Yang; Fang, Lichun; Sun, Xiaolong; Chang, Shuang; Zhao, Peng; Cui, Zhizhong

    2016-06-01

    Transduction of oncogenes by ALVs and generation of acute transforming viruses is common in natural viral infections. In order to understand the molecular basis for the rapid oncogenicity of Fu-J, an acutely transforming avian leukosis virus isolated from fibrosarcomas in crossbreed broilers infected with subgroup J avian leukosis virus (ALV-J) in China, complete genomic structure of Fu-J virus was determined by PCR amplification and compared with those of Fu-J1, Fu-J2, Fu-J3, Fu-J4, and Fu-J5 reported previously. The results showed that the genome of Fu-J was defective, with parts of gag gene replaced by the complete v-fps oncogene and encoded a 137 kDa Gag-fps fusion protein. Sequence analysis revealed that Fu-J and Fu-J1 to Fu-J5 were related quasi-species variants carrying different lengths of v-fps oncogenes generated from recombination between helper virus and c-fps gene. Comparison of virus carrying v-fps oncogene also gave us a glimpse of the molecular characterization and evolution process of the acutely transforming ALV.

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

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    Erica L Cain

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

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

    Science.gov (United States)

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

    2015-12-01

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

  19. Effect of track structure and radioprotectors on the induction of oncogenic transformation in murine fibroblasts by heavy ions

    Science.gov (United States)

    Miller, R. C.; Martin, S. G.; Hanson, W. R.; Marino, S. A.; Hall, E. J.

    1998-11-01

    The oncogenic potential of high-energy 56Fe particles (1 GeV/nucleon) accelerated with the Alternating Gradient Synchrotron at the Brookhaven National Laboratory was examined utilizing the mouse C3H 10T12 cell model. The dose-averaged LET for high-energy 56Fe is estimated to be 143 keV/μm with the exposure conditions used in this study. For 56Fe ions, the maximum relative biological effectiveness (RBEmax) values for cell survival and oncogenic transformation were 7.71 and 16.5 respectively. Compared to 150 keV/μm 4He nuclei, high-energy 56Fe nuclei were significantly less effective in cell killing and oncogenic induction. The prostaglandin E1 analog misoprostol, an effective oncoprotector of C3H 10T12 cells exposed to X rays, was evaluated for its potential as a radioprotector of oncogenic transformation with high-energy 56Fe. Exposure of cells to misoprostol did not alter 56Fe cytotoxicity or the rate of 56Fe-induced oncogenic transformation.

  20. Two oncogenes, v-fos and v-ras, cooperate to convert normal keratinocytes to squamous cell carcinoma

    Energy Technology Data Exchange (ETDEWEB)

    Greenhalgh, D.A.; Welty, D.J.; Player, A.; Yuspa, S.H. (National Cancer Institute, Bethesda, MD (USA))

    1990-01-01

    Previous studies have been implicated the ras{sup Ha} oncogene in the initiation of skin carcinogenesis and the fos oncogene in malignant progression of premalignant skin cell lines. To determine if these two oncogenes are sufficient to convert normal keratinocytes to cancer cells, freshly isolated mouse keratinocytes were coinfected with replication-defective ({psi}-2) v-ras{sup Ha} and v-fos viruses in culture. When tested in nude mice within several days of infection, v-fos/v-ras{sup Ha}-coinfected keratinocytes produced squamous cell carcinomas. Introduction of v-fos alone resulted in normal or hyperplastic skin, whereas v-ras{sup Ha} alone produced squamous papillomas. These results indicate that two oncogenes are sufficient to produce the malignant phenotype in epidermal cells. Furthermore, they clearly link the fos oncogene with malignant conversion. Since fos acts as a transcriptional regulator of other genes, malignant conversion may be an indirect consequence of the overexpression of the fos-encoded protein leading to a change in the expression of fos-controlled cellular genes.

  1. Integrated analysis of global mRNA and protein expression data in HEK293 cells overexpressing PRL-1.

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    Carmen M Dumaual

    Full Text Available BACKGROUND: The protein tyrosine phosphatase PRL-1 represents a putative oncogene with wide-ranging cellular effects. Overexpression of PRL-1 can promote cell proliferation, survival, migration, invasion, and metastasis, but the underlying mechanisms by which it influences these processes remain poorly understood. METHODOLOGY: To increase our comprehension of PRL-1 mediated signaling events, we employed transcriptional profiling (DNA microarray and proteomics (mass spectrometry to perform a thorough characterization of the global molecular changes in gene expression that occur in response to stable PRL-1 overexpression in a relevant model system (HEK293. PRINCIPAL FINDINGS: Overexpression of PRL-1 led to several significant changes in the mRNA and protein expression profiles of HEK293 cells. The differentially expressed gene set was highly enriched in genes involved in cytoskeletal remodeling, integrin-mediated cell-matrix adhesion, and RNA recognition and splicing. In particular, members of the Rho signaling pathway and molecules that converge on this pathway were heavily influenced by PRL-1 overexpression, supporting observations from previous studies that link PRL-1 to the Rho GTPase signaling network. In addition, several genes not previously associated with PRL-1 were found to be significantly altered by its expression. Most notable among these were Filamin A, RhoGDIα, SPARC, hnRNPH2, and PRDX2. CONCLUSIONS AND SIGNIFICANCE: This systems-level approach sheds new light on the molecular networks underlying PRL-1 action and presents several novel directions for future, hypothesis-based studies.

  2. Systemic delivery of siRNA by actively targeted polyion complex micelles for silencing the E6 and E7 human papillomavirus oncogenes.

    Science.gov (United States)

    Nishida, Haruka; Matsumoto, Yoko; Kawana, Kei; Christie, R James; Naito, Mitsuru; Kim, Beob Soo; Toh, Kazuko; Min, Hyun Su; Yi, Yu; Matsumoto, Yu; Kim, Hyun Jin; Miyata, Kanjiro; Taguchi, Ayumi; Tomio, Kensuke; Yamashita, Aki; Inoue, Tomoko; Nakamura, Hiroe; Fujimoto, Asaha; Sato, Masakazu; Yoshida, Mitsuyo; Adachi, Katsuyuki; Arimoto, Takahide; Wada-Hiraike, Osamu; Oda, Katsutoshi; Nagamatsu, Takeshi; Nishiyama, Nobuhiro; Kataoka, Kazunori; Osuga, Yutaka; Fujii, Tomoyuki

    2016-06-10

    Human papillomavirus (HPV) E6 and E7 oncogenes are essential for the immortalization and maintenance of HPV-associated cancer and are ubiquitously expressed in cervical cancer lesions. Small interfering RNA (siRNA) coding for E6 and E7 oncogenes is a promising approach for precise treatment of cervical cancer, yet a delivery system is required for systemic delivery to solid tumors. Here, an actively targeted polyion complex (PIC) micelle was applied to deliver siRNAs coding for HPV E6/E7 to HPV cervical cancer cell tumors in immune-incompetent tumor-bearing mice. A cell viability assay revealed that both HPV type 16 and 18 E6/E7 siRNAs (si16E6/E7 and si18E6/E7, respectively) interfered with proliferation of cervical cancer cell lines in an HPV type-specific manner. A fluorescence imaging biodistribution analysis further revealed that fluorescence dye-labeled siRNA-loaded PIC micelles efficiently accumulated within the tumor mass after systemic administration. Ultimately, intravenous injection of si16E6/E7 and si18E6/E7-loaded PIC micelles was found to significantly suppress the growth of subcutaneous SiHa and HeLa tumors, respectively. The specific activity of siRNA treatment was confirmed by the observation that p53 protein expression was restored in the tumors excised from the mice treated with si16E6/E7- and si18E6/E7-loaded PIC micelles for SiHa and HeLa tumors, respectively. Therefore, the actively targeted PIC micelle incorporating HPV E6/E7-coding siRNAs demonstrated its therapeutic potential against HPV-associated cancer. Copyright © 2016 Elsevier B.V. All rights reserved.

  3. Optimal Down Regulation of mRNA Translation

    Science.gov (United States)

    Zarai, Yoram; Margaliot, Michael; Tuller, Tamir

    2017-01-01

    Down regulation of mRNA translation is an important problem in various bio-medical domains ranging from developing effective medicines for tumors and for viral diseases to developing attenuated virus strains that can be used for vaccination. Here, we study the problem of down regulation of mRNA translation using a mathematical model called the ribosome flow model (RFM). In the RFM, the mRNA molecule is modeled as a chain of n sites. The flow of ribosomes between consecutive sites is regulated by n + 1 transition rates. Given a set of feasible transition rates, that models the outcome of all possible mutations, we consider the problem of maximally down regulating protein production by altering the rates within this set of feasible rates. Under certain conditions on the feasible set, we show that an optimal solution can be determined efficiently. We also rigorously analyze two special cases of the down regulation optimization problem. Our results suggest that one must focus on the position along the mRNA molecule where the transition rate has the strongest effect on the protein production rate. However, this rate is not necessarily the slowest transition rate along the mRNA molecule. We discuss some of the biological implications of these results.

  4. Optimal Down Regulation of mRNA Translation

    Science.gov (United States)

    Zarai, Yoram; Margaliot, Michael; Tuller, Tamir

    2017-01-01

    Down regulation of mRNA translation is an important problem in various bio-medical domains ranging from developing effective medicines for tumors and for viral diseases to developing attenuated virus strains that can be used for vaccination. Here, we study the problem of down regulation of mRNA translation using a mathematical model called the ribosome flow model (RFM). In the RFM, the mRNA molecule is modeled as a chain of n sites. The flow of ribosomes between consecutive sites is regulated by n + 1 transition rates. Given a set of feasible transition rates, that models the outcome of all possible mutations, we consider the problem of maximally down regulating protein production by altering the rates within this set of feasible rates. Under certain conditions on the feasible set, we show that an optimal solution can be determined efficiently. We also rigorously analyze two special cases of the down regulation optimization problem. Our results suggest that one must focus on the position along the mRNA molecule where the transition rate has the strongest effect on the protein production rate. However, this rate is not necessarily the slowest transition rate along the mRNA molecule. We discuss some of the biological implications of these results. PMID:28120903

  5. Gene Manipulation of Human Embryonic Stem Cells by In Vitro-Synthesized mRNA for Gene Therapy.

    Science.gov (United States)

    Wang, Xiao Li; Yu, Li; Ding, Yan; Guo, Xing Rong; Yuan, Ya Hong; Li, Dong Sheng

    2015-01-01

    The difficulty in producing genetically modified human embryonic stem cells (hESCs) limits research on their applications. Virus-based gene transfer is not safe for clinical use, whereas DNAbased non-viral methods are not efficient or safe, and mRNA-based methods are useful for genetic manipulation. In this study, we easily obtained multiple types and large amounts of in vitro-synthesized mRNA by PCR. The efficiency of different transfection methods was studied by flow cytometry. The effect of different mRNA modifications on protein translation efficiency and dynamics of luciferase mRNA expression in hESCs were studied using a bioluminescence imaging system. The pluripotency of hESCs after transfection was studied by immunofluorescence. In vitro-synthesized pancreatic-duodenal homeobox 1 (PDX1) mRNA was used to induce the differentiation of hESCs into insulin-producing cells. We found that electroporation is the most efficient transfection method, and it produces more than 95% transgene expression in multiple hESC lines. Synthesized mRNA with a combination of a polyA tail, cap and base analogues is more efficiently translated into protein in hESCs compared with single-modified mRNA. Transfection of mRNA into hESCs by trypsinizing the cells into single-cell suspensions did not affect their pluripotency, and multiple types of mRNAs can be transfected into hESCs efficiently. We found that PDX-1 mRNA transfection significantly improved the expression level of genes related to beta cells and differentiated cells that express insulin and C-peptide. ELISA analysis validate the insulin secretion of islet-like cell clusters in response to glucose stimulation. Our results indicate that electroporation of in vitro-synthesized mRNA is useful for genetic manipulation of hESCs and differentiation of hESCs into particular cell types, and this finding will pave the way for clinical applications of this method.

  6. Inhibition of the Pim1 oncogene results in diminished visual function.

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    Jun Yin

    Full Text Available Our objective was to profile genetic pathways whose differential expression correlates with maturation of visual function in zebrafish. Bioinformatic analysis of transcriptomic data revealed Jak-Stat signalling as the pathway most enriched in the eye, as visual function develops. Real-time PCR, western blotting, immunohistochemistry and in situ hybridization data confirm that multiple Jak-Stat pathway genes are up-regulated in the zebrafish eye between 3-5 days post-fertilisation, times associated with significant maturation of vision. One of the most up-regulated Jak-Stat genes is the proto-oncogene Pim1 kinase, previously associated with haematological malignancies and cancer. Loss of function experiments using Pim1 morpholinos or Pim1 inhibitors result in significant diminishment of visual behaviour and function. In summary, we have identified that enhanced expression of Jak-Stat pathway genes correlates with maturation of visual function and that the Pim1 oncogene is required for normal visual function.

  7. Systematic analysis of human oncogenic viruses in colon cancer revealed EBV latency in lymphoid infiltrates.

    Science.gov (United States)

    Fiorina, Loretta; Ricotti, Mattia; Vanoli, Alessandro; Luinetti, Ombretta; Dallera, Elena; Riboni, Roberta; Paolucci, Stefania; Brugnatelli, Silvia; Paulli, Marco; Pedrazzoli, Paolo; Baldanti, Fausto; Perfetti, Vittorio

    2014-01-01

    Environmental factors may play a role in colon cancer. In this view, several studies investigated tumor samples for the presence of various viral DNA with conflicting results. We undertook a systematic DNA analysis of 44 consecutive, prospectively collected primary tumor samples by real time and qualitative PCR for viruses of known or potential oncogenic role in humans, including polyomavirus (JCV, BKV, Merkel cell polyomavirus), HPV, HTLV, HHV-8 and EBV. Negative controls consisted of surgical resection margins. No evidence of genomic DNA fragments from tested virus were detected, except for EBV, which was found in a significant portion of tumors (23/44, 52%). Real-time PCR showed that EBV DNA was present at a highly variable content (median 258 copies in 10(5) cells, range 15-4837). Presence of EBV DNA had a trend to be associated with high lymphocyte infiltration (p = 0.06, χ2 test), and in situ hybridization with EBER1-2 probes revealed latency in a fraction of these lymphoid cells, with just a few scattered plasma cells positive for BZLF-1, an immediate early protein expressed during lytic replication. LMP-1 expression was undetectable by immunohistochemistry. These results argue against a significant involvement of the tested oncogenic viruses in established colon cancer.

  8. Anti-Differentiation Effect of Oncogenic Met Receptor in Terminally-Differentiated Myotubes

    Directory of Open Access Journals (Sweden)

    Valentina Sala

    2015-02-01

    Full Text Available Activation of the hepatocyte growth factor/Met receptor is involved in muscle regeneration, through promotion of proliferation and inhibition of differentiation in myogenic stem cells (MSCs. We previously described that the specific expression of an oncogenic version of the Met receptor (Tpr–Met in terminally-differentiated skeletal muscle causes muscle wasting in vivo. Here, we induced Tpr–Met in differentiated myotube cultures derived from the transgenic mouse. These cultures showed a reduced protein level of myosin heavy chain (MyHC, increased phosphorylation of Erk1,2 MAPK, the formation of giant sacs of myonuclei and the collapse of elongated myotubes. Treatment of the cultures with an inhibitor of the MAPK kinase pathway or with an inhibitor of the proteasome increased the expression levels of MyHC. In addition, the inhibition of the MAPK kinase pathway prevented the formation of myosacs and myotube collapse. Finally, we showed that induction of Tpr–Met in primary myotubes was unable to produce endoreplication in their nuclei. In conclusion, our data indicate that multinucleated, fused myotubes may be forced to disassemble their contractile apparatus by the Tpr–Met oncogenic factor, but they resist the stimulus toward the reactivation of the cell cycle.

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

    Science.gov (United States)

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

    2017-05-01

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

  10. Targeted tumor-penetrating siRNA nanocomplexes for credentialing the ovarian cancer oncogene ID4.

    Science.gov (United States)

    Ren, Yin; Cheung, Hiu Wing; von Maltzhan, Geoffrey; Agrawal, Amit; Cowley, Glenn S; Weir, Barbara A; Boehm, Jesse S; Tamayo, Pablo; Karst, Alison M; Liu, Joyce F; Hirsch, Michelle S; Mesirov, Jill P; Drapkin, Ronny; Root, David E; Lo, Justin; Fogal, Valentina; Ruoslahti, Erkki; Hahn, William C; Bhatia, Sangeeta N

    2012-08-15

    The comprehensive characterization of a large number of cancer genomes will eventually lead to a compendium of genetic alterations in specific cancers. Unfortunately, the number and complexity of identified alterations complicate endeavors to identify biologically relevant mutations critical for tumor maintenance because many of these targets are not amenable to manipulation by small molecules or antibodies. RNA interference provides a direct way to study putative cancer targets; however, specific delivery of therapeutics to the tumor parenchyma remains an intractable problem. We describe a platform for the discovery and initial validation of cancer targets, composed of a systematic effort to identify amplified and essential genes in human cancer cell lines and tumors partnered with a novel modular delivery technology. We developed a tumor-penetrating nanocomplex (TPN) that comprised small interfering RNA (siRNA) complexed with a tandem tumor-penetrating and membrane-translocating peptide, which enabled the specific delivery of siRNA deep into the tumor parenchyma. We used TPN in vivo to evaluate inhibitor of DNA binding 4 (ID4) as a novel oncogene. Treatment of ovarian tumor-bearing mice with ID4-specific TPN suppressed growth of established tumors and significantly improved survival. These observations not only credential ID4 as an oncogene in 32% of high-grade ovarian cancers but also provide a framework for the identification, validation, and understanding of potential therapeutic cancer targets.

  11. Oncogene Mimicry as a Mechanism of Primary Resistance to BRAF Inhibitors

    Directory of Open Access Journals (Sweden)

    Martin L. Sos

    2014-08-01

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

  12. MicroRNA29a regulates the expression of the nuclear oncogene Ski.

    Science.gov (United States)

    Teichler, Sabine; Illmer, Thomas; Roemhild, Josephine; Ovcharenko, Dmitriy; Stiewe, Thorsten; Neubauer, Andreas

    2011-08-18

    MicroRNAs (miRNAs) are small, noncoding RNA molecules that regulate growth and differentiation. miRNAs are frequently located at cancer-specific fragile sites in the human genome, such as chromosome 7q. The nuclear oncogene SKI is up-regulated in acute myeloid leukemia (AML) with -7/del7q. Here we asked whether loss of miRNAs on chromosome 7q may explain this up-regulation. miR-29a expression was found to be down-regulated in AML with -7/del7q. Forced expression of miR-29a down-regulated Ski and its target gene, Nr-CAM, whereas miR-29a inhibition induced Ski expression. Luciferase assays validated a functional binding site for miR-29a in the 3' untranslated region of SKI. Finally, in samples of AML patients, we observed an inverse correlation of Ski and miR-29a expression, respectively. In conclusion, up-regulation of Ski in AML with -7/del7q is caused by loss of miR-29a. miR-29a may therefore function as an important tumor suppressor in AML by restraining expression of the SKI oncogene.

  13. Genetic and pharmacological suppression of oncogenic mutations in RAS genes of yeast and humans

    Energy Technology Data Exchange (ETDEWEB)

    Schafer, W.R.; Sterne, R.; Thorner, J.; Rine, J.; Kim, R.; Kim, S.H. (Lawrece Berkeley Lab., CA (USA))

    1989-07-28

    The activity of an oncoprotein and the secretion of a pheromone can be affected by an unusual protein modification. Specifically, posttranslational modification of yeast-a-factor and Ras protein requires an intermediate of the cholesterol biosynthetic pathway. This modification is apparently essential for biological activity. Studies of yeast mutants blocked in sterol biosynthesis demonstrated that the membrane association and biological activation of the yeast Ras2 protein require mevalonate, a precursor of sterols and other isoprenes such as farnesyl pyrophosphate. Furthermore, drugs that inhibit mevalonate biosynthesis blocked the in vivo action of oncogenic derivatives of human Ras protein in the Xenopus oocyte assay. The same drugs and mutations also prevented the posttranslational processing and secretion of yeast a-factor, a peptide that is farnesylated. Thus, the mevalonate requirement for Ras activation may indicate that attachment of a mevalonate-derived (isoprenoid) moiety to Ras proteins is necessary for membrane association and biological function. These observations establish a connection between the cholesterol biosynthetic pathway and transformation by the ras oncogene and offer a novel pharmacological approach to investigating, and possibly controlling, ras-mediated malignant transformations. 50 refs., 3 figs., 3 tabs.

  14. CLK2 Is an Oncogenic Kinase and Splicing Regulator in Breast Cancer.

    Science.gov (United States)

    Yoshida, Taku; Kim, Jee Hyun; Carver, Kristopher; Su, Ying; Weremowicz, Stanislawa; Mulvey, Laura; Yamamoto, Shoji; Brennan, Cameron; Mei, Shenglin; Long, Henry; Yao, Jun; Polyak, Kornelia

    2015-04-01

    Genetically activated kinases have been attractive therapeutic targets in cancer due to the relative ease of developing tumor-specific treatment strategies for them. To discover novel putative oncogenic kinases, we identified 26 genes commonly amplified and overexpressed in breast cancer and subjected them to a lentiviral shRNA cell viability screen in a panel of breast cancer cell lines. Here, we report that CLK2, a kinase that phosphorylates SR proteins involved in splicing, acts as an oncogene in breast cancer. Deregulated alternative splicing patterns are commonly observed in human cancers but the underlying mechanisms and functional relevance are still largely unknown. CLK2 is amplified and overexpressed in a significant fraction of breast tumors. Downregulation of CLK2 inhibits breast cancer growth in cell culture and in xenograft models and it enhances cell migration and invasion. Loss of CLK2 in luminal breast cancer cells leads to the upregulation of epithelial-to-mesenchymal transition (EMT)-related genes and a switch to mesenchymal splice variants of several genes, including ENAH (MENA). These results imply that therapeutic targeting of CLK2 may be used to modulate EMT splicing patterns and to inhibit breast tumor growth.

  15. Lentivirus-Mediated Oncogene Introduction into Mammary Cells In Vivo Induces Tumors

    Directory of Open Access Journals (Sweden)

    Stefan K. Siwko

    2008-07-01

    Full Text Available We recently reported the introduction of oncogene-expressing avian retroviruses into somatic mammary cells in mice susceptible to infection by transgenic expression of tva, encoding the receptor for subgroup A avian leukosis-sarcoma virus (ALSV. Because ALSV-based vectors poorly infect nondividing cells, they are inadequate for studying carcinogenesis initiated from nonproliferative cells (e.g., stem cells. Lentivirus pseudotyped with the envelope protein of ALSV infects nondividing TVA-producing cells in culture but has not previously been tested for introducing genes in vivo. Here, we demonstrate that these vectors infected mammary cells in vivo when injected into the mammary ductal lumen of mice expressing tva under the control of the keratin 19 promoter. Furthermore, intraductal injection of this lentiviral vector carrying the polyoma middle T antigen gene induced atypical ductal hyperplasia and ductal carcinoma in situ-like premalignant lesions in 30 days and palpable invasive tumors at a median latency of 3.3 months. Induced tumors were a mixed epithelial/myoepithelial histologic diagnosis, occasionally displayed squamous metaplasia, and were estrogen receptor-negative. This work demonstrates the first use of a lentiviral vector to introduce oncogenes for modeling cancer in mice, and this vector system may be especially suitable for introducing genetic alterations into quiescent cells in vivo.

  16. Oncogene Mutations in Colorectal Polyps Identified in the Norwegian Colorectal Cancer Prevention (NORCCAP) Screening Study

    Science.gov (United States)

    Lorentzen, Jon A.; Grzyb, Krzysztof; De Angelis, Paula M.; Hoff, Geir; Eide, Tor J.; Andresen, Per Arne

    2016-01-01

    Data are limited on oncogene mutation frequencies in polyps from principally asymptomatic participants of population-based colorectal cancer screening studies. In this study, DNA from 204 polyps, 5 mm or larger, were collected from 176 participants of the NORCCAP screening study and analyzed for mutations in KRAS, BRAF, and PIK3CA including the rarely studied KRAS exons 3 and 4 mutations. KRAS mutations were identified in 23.0% of the lesions and were significantly associated with tubulovillous adenomas and large size. A significantly higher frequency of KRAS mutations in females was associated with mutations in codon 12. The KRAS exon 3 and 4 mutations constituted 23.4% of the KRAS positive lesions, which is a larger proportion compared to previous observations in colorectal cancer. BRAF mutations were identified in 11.3% and were associated with serrated polyps. None of the individuals were diagnosed with de novo or recurrent colorectal cancer during the follow-up time (median 11.2 years). Revealing differences in mutation-spectra according to gender and stages in tumorigenesis might be important for optimal use of oncogenes as therapeutic targets and biomarkers. PMID:27656095

  17. Drosophila PRL-1 is a growth inhibitor that counteracts the function of the Src oncogene.

    Science.gov (United States)

    Pagarigan, Krystle T; Bunn, Bryce W; Goodchild, Jake; Rahe, Travis K; Weis, Julie F; Saucedo, Leslie J

    2013-01-01

    Phosphatase of Regenerating Liver (PRL) family members have emerged as molecular markers that significantly correlate to the ability of many cancers to metastasize. However, contradictory cellular responses to PRL expression have been reported, including the inhibition of cell cycle progression. An obvious culprit for the discrepancy is the use of dozens of different cell lines, including many isolated from tumors or cultured cells selected for immortalization which may have missing or mutated modulators of PRL function. We created transgenic Drosophila to study the effects of PRL overexpression in a genetically controlled, organismal model. Our data support the paradigm that the normal cellular response to high levels of PRL is growth suppression and furthermore, that PRL can counter oncogenic activity of Src. The ability of PRL to inhibit growth under normal conditions is dependent on a CAAX motif that is required to localize PRL to the apical edge of the lateral membrane. However, PRL lacking the CAAX motif can still associate indiscriminately with the plasma membrane and retains its ability to inhibit Src function. We propose that PRL binds to other membrane-localized proteins that are effectors of Src or to Src itself. This first examination of PRL in a model organism demonstrates that PRL performs as a tumor suppressor and underscores the necessity of identifying the conditions that enable it to transform into an oncogene in cancer.

  18. RUNX3 has an oncogenic role in head and neck cancer.

    Directory of Open Access Journals (Sweden)

    Takaaki Tsunematsu

    Full Text Available BACKGROUND: Runt-related transcription factor 3 (RUNX3 is a tumor suppressor of cancer and appears to be an important component of the transforming growth factor-beta (TGF-ss-induced tumor suppression pathway. Surprisingly, we found that RUNX3 expression level in head and neck squamous cell carcinoma (HNSCC tissues, which is one of the most common types of human cancer, was higher than that in normal tissues by a previously published microarray dataset in our preliminary study. Therefore, here we examined the oncogenic role of RUNX3 in HNSCC. PRINCIPAL FINDINGS: Frequent RUNX3 expression and its correlation with malignant behavior were observed in HNSCC. Ectopic RUNX3 overexpression promoted cell growth and inhibited serum starvation-induced apoptosis and chemotherapeutic drug induced apoptosis in HNSCC cells. These findings were confirmed by RUNX3 knockdown. Moreover, RUNX3 overexpression enhanced tumorsphere formation. RUNX3 expression level was well correlated with the methylation status in HNSCC cells. Moreover, RUNX3 expression was low due to the methylation of its promoter in normal oral epithelial cells. CONCLUSIONS/SIGNIFICANCE: Our findings suggest that i RUNX3 has an oncogenic role in HNSCC, ii RUNX3 expression observed in HNSCC may be caused in part by demethylation during cancer development, and iii RUNX3 expression can be a useful marker for predicting malignant behavior and the effect of chemotherapeutic drugs in HNSCC.

  19. Methylation profile and amplification of proto-oncogenes in rat pancreas induced with phytoestrogens

    Energy Technology Data Exchange (ETDEWEB)

    Lyn-Cook, B.D.; Blann, E.; Bo, J. [National Center for Toxicological Research, Jefferson, AR (United States)

    1995-01-01

    Specific gene hypermethylation has been shown in DNA from neonatal rats exposed to the phytoestrogens, coumestrol, and equol. The pancreas is an organ in which estrogen receptors have been shown to be present. Studies have correlated the development of acute pancreatitis with rising levels of human estrogen binding proteins. Neonatal rats were dosed with 10 or 100 {mu}g of coumestrol or equol on postnatal day (PND) 1-10. The animals were sacrificed at Day 15. The pancreas was excised and pancreatic acinar cells isolated for molecular analysis. DNA was isolated from the cells by lysis in TEN-9 buffer supplemented with proteinase K and 0.1% SDS. High molecular weight (HMW) DNA was digested with the methylated DNA specific restriction enzymes, Hpa II and Msp I, for determination of methylation profiles. Both coumestrol and equol at high doses caused hypermethylation of the c-H-ras proto-oncogene. No hypermethylation or hypomethylation was observed in the proto-oncogenes, c-myc or c-fos. Methylation is thought to be an epigenetic mechanism involved in the activation (hypomethylation) or inactivation (hypermethylation) of cellular genes which are known to play a role in carcinogenesis. Epidemiology studies have shown that equol may have anti-carcinogenic effects on some hormone-dependent cancers. Additional studies are needed to further understand the role of phytoestrogens and methylation in relation to pancreatic disorders. 15 refs., 4 figs.

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

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    Faure Claudine

    2007-10-01

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

  1. The oncogenic roles of Notch1 in astrocytic gliomas in vitro and in vivo.

    Science.gov (United States)

    Xu, Peng; Qiu, Mingzhe; Zhang, Zhiyong; Kang, Chunsheng; Jiang, Rongcai; Jia, Zhifan; Wang, Guangxiu; Jiang, Hao; Pu, Peiyu

    2010-03-01

    Notch receptors play an essential role in cellular processes during embryonic and postnatal development, including maintenance of stem cell self-renewal, proliferation, and determination of cell fate and apoptosis. Deregulation of Notch signaling has been implicated in some genetic diseases and tumorigenesis. The function of Notch signaling in a variety of tumors can be either oncogenic or tumor-suppressive, depending on the cellular context. In this study, Notch1 overexpression was observed in the majority of 45 astrocytic gliomas with different grades and in U251MG glioma cells. Transfection of siRNA targeting Notch1 into U251 cells in vitro downregulated Notch1 expression, associated with inhibition of cell growth, arrest of cell cycle, reduction of cell invasiveness, and induction of cell apoptosis. Meanwhile, tumor growth was delayed in established subcutaneous gliomas in nude mice treated with Notch1 siRNA in vivo. These results suggest that Notch1 plays an important oncogenic role in the development and progression of astrocytic gliomas. Furthermore, knockdown of Notch1 expression by siRNA simultaneously downregulated the expression of EGFR and the important components of its downstream pathways, including PI3K, p-AKT, K-Ras, cyclin D1 and MMP9, indicating the crosstalk and interaction of Notch and EGFR signaling pathways.

  2. Hepatocellular alterations and dysregulation of oncogenic pathways in the liver of transgenic mice overexpressing growth hormone.

    Science.gov (United States)

    Miquet, Johanna G; Freund, Thomas; Martinez, Carolina S; González, Lorena; Díaz, María E; Micucci, Giannina P; Zotta, Elsa; Boparai, Ravneet K; Bartke, Andrzej; Turyn, Daniel; Sotelo, Ana I

    2013-04-01

    Growth hormone (GH) overexpression throughout life in transgenic mice is associated with the development of liver tumors at old ages. The preneoplastic pathology observed in the liver of young adult GH-overexpressing mice is similar to that present in humans at high risk of hepatic cancer. To elucidate the molecular pathogenesis underlying the pro-oncogenic liver pathology induced by prolonged exposure to elevated GH levels, the activation and expression of several components of signal transduction pathways that have been implicated in hepatocellular carcinogenesis were evaluated in the liver of young adult GH-transgenic mice. In addition, males and females were analyzed in parallel in order to evaluate sexual dimorphism. Transgenic mice from both sexes exhibited hepatocyte hypertrophy with enlarged nuclear size and exacerbated hepatocellular proliferation, which were higher in males. Dysregulation of several oncogenic pathways was observed in the liver of GH-overexpressing transgenic mice. Many signaling mediators and effectors were upregulated in transgenic mice compared with normal controls, including Akt2, NFκB, GSK3β, β-catenin, cyclin D1, cyclin E, c-myc, c-jun and c-fos. The molecular alterations described did not exhibit sexual dimorphism in transgenic mice except for higher gene expression and nuclear localization of cyclin D1 in males. We conclude that prolonged exposure to GH induces in the liver alterations in signaling pathways involved in cell growth, proliferation and survival that resemble those found in many human tumors.

  3. mTORC1 is a critical mediator of oncogenic Semaphorin3A signaling

    Energy Technology Data Exchange (ETDEWEB)

    Yamada, Daisuke; Kawahara, Kohichi; Maeda, Takehiko, E-mail: maeda@nupals.ac.jp

    2016-08-05

    Aberration of signaling pathways by genetic mutations or alterations in the surrounding tissue environments can result in tumor development or metastasis. However, signaling molecules responsible for these processes have not been completely elucidated. Here, we used mouse Lewis lung carcinoma cells (LLC) to explore the mechanism by which the oncogenic activity of Semaphorin3A (Sema3A) signaling is regulated. Sema3A knockdown by shRNA did not affect apoptosis, but decreased cell proliferation in LLCs; both the mammalian target of rapamycin complex 1 (mTORC1) level and glycolytic activity were also decreased. In addition, Sema3A knockdown sensitized cells to inhibition of oxidative phosphorylation by oligomycin, but conferred resistance to decreased cell viability induced by glucose starvation. Furthermore, recombinant SEMA3A rescued the attenuation of cell proliferation and glycolytic activity in LLCs after Sema3A knockdown, whereas mTORC1 inhibition by rapamycin completely counteracted this effect. These results demonstrate that Sema3A signaling exerts its oncogenic effect by promoting an mTORC1-mediated metabolic shift from oxidative phosphorylation to aerobic glycolysis. -- Highlights: •Sema3A knockdown decreased proliferation of Lewis lung carcinoma cells (LLCs). •Sema3A knockdown decreased mTORC1 levels and glycolytic activity in LLCs. •Sema3A knockdown sensitized cells to inhibition of oxidative phosphorylation. •Sema3A promotes shift from oxidative phosphorylation to aerobic glycolysis via mTORC1.

  4. RUNX3 is a novel negative regulator of oncogenic TEAD-YAP complex in gastric cancer.

    Science.gov (United States)

    Qiao, Y; Lin, S J; Chen, Y; Voon, D C-C; Zhu, F; Chuang, L S H; Wang, T; Tan, P; Lee, S C; Yeoh, K G; Sudol, M; Ito, Y

    2016-05-19

    Runt-related transcription factor 3 (RUNX3) is a well-documented tumour suppressor that is frequently inactivated in gastric cancer. Here, we define a novel mechanism by which RUNX3 exerts its tumour suppressor activity involving the TEAD-YAP complex, a potent positive regulator of proliferative genes. We report that the TEAD-YAP complex is not only frequently hyperactivated in liver and breast cancer, but also confers a strong oncogenic activity in gastric epithelial cells. The increased expression of TEAD-YAP in tumour tissues significantly correlates with poorer overall survival of gastric cancer patients. Strikingly, RUNX3 physically interacts with the N-terminal region of TEAD through its Runt domain. This interaction markedly reduces the DNA-binding ability of TEAD that attenuates the downstream signalling of TEAD-YAP complex. Mutation of RUNX3 at Arginine 122 to Cysteine, which was previously identified in gastric cancer, impairs the interaction between RUNX3 and TEAD. Our data reveal that RUNX3 acts as a tumour suppressor by negatively regulating the TEAD-YAP oncogenic complex in gastric carcinogenesis.

  5. Effects of cadmium on cell proliferation, apoptosis, and proto-oncogene expression in zebrafish liver cells

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Ying Ying; Zhu, Jin Yong; Chan, King Ming, E-mail: kingchan@cuhk.edu.hk

    2014-12-15

    Highlights: • Cd stimulated ZFL cell proliferation with decreasing apoptotic cell numbers. • Cd down regulated p53 and RAD51. • Cd up regulated immediate early cancer genes of GADD45 and growth factors. • Cd promoted tumorigenic effects in ZFL cells. - Abstract: Cadmium (Cd) is one of the major transitional metal that has toxic effects in aquatic organisms and their associated ecosystem; however, its hepatic toxicity and carcinogenicity are not very well characterized. We used a zebrafish liver (ZFL) cell line as a model to investigate the mechanism of Cd-induced toxicity on hepatocytes. Our results showed that Cd can be effectively accumulated in ZFL cells in our exposure experiments. Cell cytotoxicity assays and flow cytometer measurements revealed that Cd{sup 2+} stimulated ZFL cell proliferation with decreasing apoptotic cell numbers indicating potentially tumorigenic effects of Cd in ZFL cells. Gene expression profiles also indicated that Cd downregulated oncogenes p53 and rad51 and upregulated immediate response oncogenes, growth arrest and DNA damage-inducible (gadd45) genes, and growth factors. We also found dramatic changes in the gene expression of c-jun and igf1rb at different exposure time points, supporting the notion that potentially tumorigenic of Cd-is involved in the activation of immediate early genes or genes related to apoptosis in cancer promotion.

  6. Complex oncogenic translocations with gene amplification are initiated by specific DNA breaks in lymphocytes.

    Science.gov (United States)

    Wright, Sarah M; Woo, Yong H; Alley, Travis L; Shirley, Bobbi-Jo; Akeson, Ellen C; Snow, Kathy J; Maas, Sarah A; Elwell, Rachel L; Foreman, Oded; Mills, Kevin D

    2009-05-15

    Chromosomal instability is a hallmark of many tumor types. Complex chromosomal rearrangements with associated gene amplification, known as complicons, characterize many hematologic and solid cancers. Whereas chromosomal aberrations, including complicons, are useful diagnostic and prognostic cancer markers, their molecular origins are not known. Although accumulating evidence has implicated DNA double-strand break repair in suppression of oncogenic genome instability, the genomic elements required for chromosome rearrangements, especially complex lesions, have not been elucidated. Using a mouse model of B-lineage lymphoma, characterized by complicon formation involving the immunoglobulin heavy chain (Igh) locus and the c-myc oncogene, we have now investigated the requirement for specific genomic segments as donors for complex rearrangements. We now show that specific DNA double-strand breaks, occurring within a narrow segment of Igh, are necessary to initiate complicon formation. By contrast, neither specific DNA breaks nor the powerful intronic enhancer Emu are required for complicon-independent oncogenesis. This study is the first to delineate mechanisms of complex versus simple instability and the first to identify specific chromosomal elements required for complex chromosomal aberrations. These findings will illuminate genomic cancer susceptibility and risk factors.

  7. Trefoil factor 3 is oncogenic and mediates anti-estrogen resistance in human mammary carcinoma.

    Science.gov (United States)

    Kannan, Nagarajan; Kang, Jian; Kong, Xiangjun; Tang, Jianzhong; Perry, Jo K; Mohankumar, Kumarasamypet M; Miller, Lance D; Liu, Edison T; Mertani, Hichem C; Zhu, Tao; Grandison, Prudence M; Liu, Dong-Xu; Lobie, Peter E

    2010-12-01

    We report herein that trefoil factor 3 (TFF3) is oncogenic and mediates anti-estrogen resistance in human mammary carcinoma. Forced expression of TFF3 in mammary carcinoma cells increased cell proliferation and survival, enhanced anchorage-independent growth, and promoted migration and invasion. Moreover, forced expression of TFF3 increased tumor size in xenograft models. Conversely, depletion of endogenous TFF3 with small interfering RNA (siRNA) decreased the oncogenicity and invasiveness of mammary carcinoma cells. Neutralization of secreted TFF3 by antibody promoted apoptosis, decreased cell growth in vitro, and arrested mammary carcinoma xenograft growth. TFF3 expression was significantly correlated to decreased survival of estrogen receptor (ER)-positive breast cancer patients treated with tamoxifen. Forced expression of TFF3 in mammary carcinoma cells increased ER transcriptional activity, promoted estrogen-independent growth, and produced resistance to tamoxifen and fulvestrant in vitro and to tamoxifen in xenograft models. siRNA-mediated depletion or antibody inhibition of TFF3 significantly enhanced the efficacy of antiestrogens. Increased TFF3 expression was observed in tamoxifen-resistant (TAMR) cells and antibody inhibition of TFF3 in TAMR cells improved tamoxifen sensitivity. Functional antagonism of TFF3 therefore warrants consideration as a novel therapeutic strategy for mammary carcinoma.

  8. Simultaneous detection, typing and quantitation of oncogenic human papillomavirus by multiplex consensus real-time PCR.

    Science.gov (United States)

    Jenkins, Andrew; Allum, Anne-Gry; Strand, Linda; Aakre, Randi Kersten

    2013-02-01

    A consensus multiplex real-time PCR test (PT13-RT) for the oncogenic human papillomavirus (HPV) types 16, 18, 31, 33, 35, 39, 45, 51, 52, 56, 58, 59 and 66 is described. The test targets the L1 gene. Analytical sensitivity is between 4 and 400 GU (genomic units) in the presence of 500 ng of human DNA, corresponding to 75,000 human cells. HPV types are grouped into multiplex groups of 3 or 4 resulting in the use of 4 wells per sample and permitting up to 24 samples per run (including controls) in a standard 96-well real-time PCR instrument. False negative results are avoided by (a) measuring sample DNA concentration to control that sufficient cellular material is present and (b) including HPV type 6 as a homologous internal control in order to detect PCR inhibition or competition from other (non-oncogenic) HPV types. Analysis time from refrigerator to report is 8 h, including 2.5 h hands-on time. Relative to the HC2 test, the sensitivity and specificity were respectively 98% and 83%, the lower specificity being attributable to the higher analytical sensitivity of PT13-RT. To assess type determination comparison was made with a reversed line-blot test. Type concordance was high (κ=0.79) with discrepancies occurring mostly in multiple-positive samples. Copyright © 2012 Elsevier B.V. All rights reserved.

  9. The non-coding oncogene: a case of missing DNA evidence?

    Directory of Open Access Journals (Sweden)

    Puja eShahrouki

    2012-09-01

    Full Text Available The evidence that links classical protein-coding proto-oncogenes and tumor suppressors, such as MYC, RAS, P53, and RB, to carcinogenesis is indisputable. Multiple lines of proof show how random somatic genomic alteration of such genes (e.g. mutation, deletion or amplification, followed by selection and clonal expansion, forms the main molecular basis of tumor development. Many important cancer genes were discovered using low-throughput approaches in the pre-genomic era, and this knowledge is today solidified and expanded upon by modern genome-scale methodologies. In several recent studies, non-coding RNAs (ncRNAs, such as microRNAs and long non-coding RNAs (lncRNAs, have been shown to contribute to tumor development. However, in comparison with coding cancer genes, the genomic (DNA-level evidence is sparse for ncRNAs. The coding proto-oncogenes and tumor suppressors that we know of today are major molecular hubs in both normal and malignant cells. The search for non-coding RNAs with tumor driver or suppressor roles therefore holds the additional promise of pinpointing important, biologically active, ncRNAs in a vast and largely uncharacterized non-coding transcriptome. Here, we assess the available DNA-level data that links non-coding genes to tumor development. We further consider historical, methodological and biological aspects, and discuss future prospects of ncRNAs in cancer.

  10. The dark and the bright side of Stat3: proto-oncogene and tumor-suppressor.

    Science.gov (United States)

    Ecker, Andrea; Simma, Olivia; Hoelbl, Andrea; Kenner, Lukas; Beug, Hartmut; Moriggl, Richard; Sexl, Veronika

    2009-01-01

    Stat transcription factors have been implicated in tumorigenesis in mice and men. Stat3 and Stat5 are considered powerful proto-oncogenes, whereas Stat1 has been demonstrated to suppress tumor formation. We demonstrate here for the first time that a constitutive active version of Stat3alpha (Stat3alphaC) may also suppress transformation. Mouse embryonic fibroblasts (MEFs) deficient for p53 can be transformed with either c-myc or with rasV12 alone. Interestingly, transformation by c-myc is efficiently suppressed by co-expression of Stat3alphaC, but Stat3alphaC does not interfere with transformation by the rasV12-oncogene. In contrast, transplantation of bone marrow cells expressing Stat3alphaC induces the formation of a highly aggressive T cell leukemia in mice. The leukemic cells invaded multiple organs including lung, heart, salivary glands, liver and kidney. Interestingly, transplanted mice developed a similar leukemia when the bone marrow cells were transduced with Stat3beta, which is also constitutively active when expressed at significant levels. Our experiments demonstrate that Stat3 has both - tumor suppressing and tumor promoting properties.

  11. Identification of anaplastic lymphoma kinase break points and oncogenic mutation profiles in acral/mucosal melanomas.

    Science.gov (United States)

    Niu, Hai-Tao; Zhou, Qi-Ming; Wang, Fang; Shao, Qiong; Guan, Yuan-Xiang; Wen, Xi-Zhi; Chen, Li-Zhen; Feng, Qi-Sheng; Li, Wei; Zeng, Yi-Xin; Zhang, Xiao-Shi

    2013-09-01

    Acral and mucosal melanomas, the two most common subtypes of melanoma in China, exhibit different genetic alterations and biologic behavior compared with other subtypes of melanomas. The purpose of this study was to identify the genetic alterations in patients with acral or mucosal melanomas in southern China. Fluorescence in situ hybridization (FISH), immunohistochemistry (IHC) analysis, polymerase chain reaction (PCR), and quantitative real-time reverse transcriptase PCR (qRT-PCR) were used to assess the anaplastic lymphoma kinase (ALK) break points. Furthermore, a mass spectrometry-based genotyping platform was used to analyze 30 acral melanomas and 28 mucosal melanomas to profile 238 known somatic mutations in 19 oncogenes. ALK break points were identified in four acral cases (6.9%). Eight (13.8%) cases harbored BRAF mutations, six (10.3%) had NRAS mutations, four (6.9%) had KIT mutations, two (3.5%) had EGFR mutations, two (3.5%) had KRAS mutations, two (3.5%) had MET mutations, one (1.7%) had an HRAS mutation, and one (1.7%) had a PIK3CA mutation. Two cases exhibited co-occurring mutations, and one case with a BRAF mutation had a translocation in ALK. This study represents a comprehensive and concurrent analysis of the major recurrent oncogenic mutations involved in melanoma cases from southern China. These data have implications for both clinical trial designs and therapeutic strategies.

  12. Complexity on Acute Myeloid Leukemia mRNA Transcript Variant

    Directory of Open Access Journals (Sweden)

    Carlo Cattani

    2011-01-01

    Full Text Available This paper deals with the sequence analysis of acute myeloid leukemia mRNA. Six transcript variants of mlf1 mRNA, with more than 2000 bps, are analyzed by focusing on the autocorrelation of each distribution. Through the correlation matrix, some patches and similarities are singled out and commented, with respect to similar distributions. The comparison of Kolmogorov fractal dimension will be also given in order to classify the six variants. The existence of a fractal shape, patterns, and symmetries are discussed as well.

  13. A block in lineage differentiation of immortal human mammary stem / progenitor cells by ectopically-expressed oncogenes

    Directory of Open Access Journals (Sweden)

    Xiangshan Zhao

    2011-01-01

    Full Text Available Introduction: Emerging evidence suggests a direct role of cancer stem cells (CSCs in the development of breast cancer. In vitro cellular models that recapitulate properties of CSCs are therefore highly desirable. We have previously shown that normal human mammary epithelial cells (hMECs immortalized with human telomerase reverse transcriptase (hTERT possess properties of mammary stem / progenitor cells. Materials and Methods: In the present study, we used this cell system to test the idea that other known hMEC-immortalizing oncogenes (RhoA, HPVE6, HPVE7, p53 mutant, and treatment with g-radiation, share with hTERT, the ability to maintain mammary stem / progenitor cells. Results: The results presented here demonstrate that similar to hMECs immortalized with hTERT, all hMEC cell lines immortalized using various oncogenic strategies express stem / progenitor cell markers. Furthermore, analyses using 2D and 3D culture assays demonstrate that all the immortal cell lines retain their ability to self-renew and to differentiate along the luminal lineage. Remarkably, the stem / progenitor cell lines generated using various oncogenic strategies exhibit a block in differentiation along the myoepithelial lineage, a trait that is retained on hTERT-immortalized stem / progenitors. The inability to differentiate along the myoepithelial lineage could be induced by ectopic mutant p53 expression in hTERT-immortalized hMEC. Conclusions: Our studies demonstrate that stem / progenitor cell characteristics of hMECs are maintained upon immortalization by using various cancer-relevant oncogenic strategies. Oncogene-immortalized hMECs show a block in their ability to differentiate along the myoepithelial lineage. Abrogation of the myoepithelial differentiation potential by a number of distinct oncogenic insults suggests a potential explanation for the predominance of luminal and rarity of myoepithelial breast cancers.

  14. Altered Ca(2+) signaling in cancer cells: proto-oncogenes and tumor suppressors targeting IP3 receptors.

    Science.gov (United States)

    Akl, Haidar; Bultynck, Geert

    2013-04-01

    Proto-oncogenes and tumor suppressors critically control cell-fate decisions like cell survival, adaptation and death. These processes are regulated by Ca(2+) signals arising from the endoplasmic reticulum, which at distinct sites is in close proximity to the mitochondria. These organelles are linked by different mechanisms, including Ca(2+)-transport mechanisms involving the inositol 1,4,5-trisphosphate receptor (IP3R) and the voltage-dependent anion channel (VDAC). The amount of Ca(2+) transfer from the endoplasmic reticulum to mitochondria determines the susceptibility of cells to apoptotic stimuli. Suppressing the transfer of Ca(2+) from the endoplasmic reticulum to the mitochondria increases the apoptotic resistance of cells and may decrease the cellular responsiveness to apoptotic signaling in response to cellular damage or alterations. This can result in the survival, growth and proliferation of cells with oncogenic features. Clearly, proper maintenance of endoplasmic reticulum Ca(2+) homeostasis and dynamics including its links with the mitochondrial network is essential to detect and eliminate altered cells with oncogenic features through the apoptotic pathway. Proto-oncogenes and tumor suppressors exploit the central role of Ca(2+) signaling by targeting the IP3R. There are an increasing number of reports showing that activation of proto-oncogenes or inactivation of tumor suppressors directly affects IP3R function and endoplasmic reticulum Ca(2+) homeostasis, thereby decreasing mitochondrial Ca(2+) uptake and mitochondrial outer membrane permeabilization. In this review, we provide an overview of the current knowledge on the proto-oncogenes and tumor suppressors identified as IP3R-regulatory proteins and how they affect endoplasmic reticulum Ca(2+) homeostasis and dynamics.

  15. MiR-520b suppresses proliferation of hepatoma cells through targeting ten-eleven translocation 1 (TET1) mRNA

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Weiying; Lu, Zhanping; Gao, Yuen [State Key Laboratory of Medicinal Chemical Biology, Department of Cancer Research, College of Life Sciences, Nankai University, Tianjin (China); Ye, Lihong [State Key Laboratory of Medicinal Chemical Biology, Department of Biochemistry, College of Life Sciences, Nankai University, Tianjin (China); Song, Tianqiang, E-mail: tjchi@hotmai.com [Tianjin Medical University Cancer Institute and Hospital, National Clinical Research Center for Cancer, Tianjin (China); Zhang, Xiaodong, E-mail: zhangxd@nankai.edu.cn [State Key Laboratory of Medicinal Chemical Biology, Department of Cancer Research, College of Life Sciences, Nankai University, Tianjin (China)

    2015-05-08

    Accumulating evidence indicates that microRNAs are able to act as oncogenes or tumor suppressor genes in human cancer. We previously reported that miR-520b was down-regulated in hepatocellular carcinoma (HCC) and its deregulation was involved in hepatocarcinogenesis. In the present study, we report that miR-520b suppresses cell proliferation in HCC through targeting the ten-eleven translocation 1 (TET1) mRNA. Notably, we identified that miR-520b was able to target 3′-untranslated region (3′UTR) of TET1 mRNA by luciferase reporter gene assays. Then, we revealed that miR-520b was able to reduce the expression of TET1 at the levels of mRNA and protein using reverse transcription-polymerase chain reaction and Western blotting analysis. In terms of function, 5-ethynyl-2-deoxyuridine (EdU) incorporation and colony formation assays demonstrated that the forced miR-520b expression remarkably inhibited proliferation of hepatoma cells, but TET1 overexpression could rescue the inhibition of cell proliferation mediated by miR-520b. Furthermore, anti-miR-520b enhanced proliferation of hepatoma cells, whereas silencing of TET1 abolished anti-miR-520b-induced acceleration of cell proliferation. Then, we validated that the expression levels of miR-520b were negatively related to those of TET1 mRNA in clinical HCC tissues. Thus, we conclude that miR-520b depresses proliferation of liver cancer cells through targeting 3′UTR of TET1 mRNA. Our finding provides new insights into the mechanism of hepatocarcinogenesis. - Highlights: • TET1 is a novel target gene of miR-520b. • TET1 is upregulated in clinical HCC tissues. • MiR-520b is negatively correlated with TET1 in clinical HCC tissues. • MiR-520b depresses the proliferation of HCC cells through targeting TET1 mRNA.

  16. The cnidarian origin of the proto-oncogenes NF-κB/STAT and WNT-like oncogenic pathway drives the ctenophores (Review).

    Science.gov (United States)

    Sinkovics, Joseph G

    2015-10-01

    The cell survival pathways of the diploblastic early multicellular eukaryotic hosts contain and operate the molecular machinery resembling those of malignantly transformed individual cells of highly advanced multicellular hosts (including Homo). In the present review, the STAT/NF-κB pathway of the cnidarian Nematostella vectensis is compared with that of human tumors (malignant lymphomas, including Reed-Sternberg cells) pointing out similarities, including possible viral initiation in both cases. In the ctenophore genome and proteome, β-catenin gains intranuclear advantages due to a physiologically weak destructive complex in the cytoplasm, and lack of natural inhibitors (the dickkopfs). Thus, a scenario similar to what tumor cells initiate and achieve is presented through several constitutive loss-of-function type mutations in the destructive complex and in the elimination of inhibitors. Vice versa, malignantly transformed individual cells of advanced multicellular hosts assume pheno-genotypic resemblance to cells of unicellular or early multicellular hosts, and presumably to their ancient predecessors, by returning to the semblance of immortality and to the resumption of the state of high degree of resistance to physicochemical insults. Human leukemogenic and oncogenic pathways are presented for comparisons. The supreme bioengineers RNA/DNA complex encoded both the malignantly transformed immortal cell and the human cerebral cortex. The former generates molecules for the immortality of cellular life in the Universe. The latter invents the inhibitors of the process in order to gain control over it.

  17. Esculetin Downregulates the Expression of AML1-ETO and C-Kit in Kasumi-1 Cell Line by Decreasing Half-Life of mRNA.

    Science.gov (United States)

    Sawney, Sharad; Arora, Rashi; Aggarwal, Kamal K; Saluja, Daman

    2015-01-01

    One of the most frequent genetic aberrations in acute myeloid leukemia (AML) is chromosomal translocation between AML1/RUNX1 on chromosome 21 and ETO gene on chromosome 8 resulting in the expression of chimeric oncogene AML1-ETO. Although patients with t(8;21) translocation have good prognosis, 5-year survival is observed only in 50% of the cases. AML1-ETO translocation is usually accompanied by overexpression of mutant C-Kit, a tyrosine kinase, which contributes to uncontrolled proliferation of premature blood cells leading to relapse and poor prognosis. We illustrate the potential use of esculetin on leukemic cell line, Kasumi-1, bearing t(8;21) translocation and mutated C-Kit gene. Esculetin decreases the expression of AML1-ETO at both protein and transcript level within 24 hours of treatment. Half-life of AML1-ETO mRNA was reduced from 7 hours to 1.5 hours. Similarly half-life of C-Kit mRNA was reduced to 2 hours from 5 hours in esculetin treated cells. Esculetin also perturbed the expression of ectopically expressed AML1-ETO in U937 cells. The decreased expression of AML1-ETO chimeric gene was associated with increased expression of LAT1 and RUNX3 genes, targets of AML1. We envisage that discovery of a drug candidate which could target both these mutated genes would be a considerable breakthrough for future application.

  18. Esculetin Downregulates the Expression of AML1-ETO and C-Kit in Kasumi-1 Cell Line by Decreasing Half-Life of mRNA

    Directory of Open Access Journals (Sweden)

    Sharad Sawney

    2015-01-01

    Full Text Available One of the most frequent genetic aberrations in acute myeloid leukemia (AML is chromosomal translocation between AML1/RUNX1 on chromosome 21 and ETO gene on chromosome 8 resulting in the expression of chimeric oncogene AML1-ETO. Although patients with t(8;21 translocation have good prognosis, 5-year survival is observed only in 50% of the cases. AML1-ETO translocation is usually accompanied by overexpression of mutant C-Kit, a tyrosine kinase, which contributes to uncontrolled proliferation of premature blood cells leading to relapse and poor prognosis. We illustrate the potential use of esculetin on leukemic cell line, Kasumi-1, bearing t(8;21 translocation and mutated C-Kit gene. Esculetin decreases the expression of AML1-ETO at both protein and transcript level within 24 hours of treatment. Half-life of AML1-ETO mRNA was reduced from 7 hours to 1.5 hours. Similarly half-life of C-Kit mRNA was reduced to 2 hours from 5 hours in esculetin treated cells. Esculetin also perturbed the expression of ectopically expressed AML1-ETO in U937 cells. The decreased expression of AML1-ETO chimeric gene was associated with increased expression of LAT1 and RUNX3 genes, targets of AML1. We envisage that discovery of a drug candidate which could target both these mutated genes would be a considerable breakthrough for future application.

  19. The proto-oncogene c-src is involved in primordial follicle activation through the PI3K, PKC and MAPK signaling pathways.

    Science.gov (United States)

    Du, Xiao-Yu; Huang, Jian; Xu, Liang-Quan; Tang, Dan-Feng; Wu, Lei; Zhang, Li-Xia; Pan, Xiao-Ling; Chen, Wei-Yun; Zheng, Li-Ping; Zheng, Yue-Hui

    2012-08-20

    C-src is an evolutionarily conserved proto-oncogene that regulates cell proliferation, differentiation and apoptosis. In our previous studies, we have reported that another proto-oncogene, c-erbB2, plays an important role in primordial follicle activation and development. We also found that c-src was expressed in mammalian ovaries, but its functions in primordial follicle activation remain unclear. The objective of this study is to investigate the role and mechanism of c-src during the growth of primordial follicles. Ovaries from 2-day-old rats were cultured in vitro for 8 days. Three c-src-targeting and one negative control siRNA were designed and used in the present study. PCR, Western blotting and primordial follicle development were assessed for the silencing efficiency of the lentivirus c-src siRNA and its effect on primordial follicle onset. The expression of c-src mRNA and protein in primordial follicle growth were examined using the PCR method and immunohistochemical staining. Furthermore, the MAPK inhibitor PD98059, the PKC inhibitor Calphostin and the PI3K inhibitor LY294002 were used to explore the possible signaling pathways of c-src in primordial folliculogenesis. The results showed that Src protein was distributed in the ooplasmic membrane and the granulosa cell membrane in the primordial follicles, and c-src expression level increased with the growth of primordial follicle. The c-src -targeting lentivirus siRNAs had a silencing effect on c-src mRNA and protein expression. Eight days after transfection of rat ovaries with c-src siRNA, the GFP fluorescence in frozen ovarian sections was clearly discernible under a fluorescence microscope, and its relative expression level was 5-fold higher than that in the control group. Furthermore, the c-src-targeting lentivirus siRNAs lowered its relative expression level 1.96 times. We also found that the development of cultured primordial follicles was completely arrested after c-src siRNA knockdown of c

  20. MRNA-based skin identification for forensic applications

    NARCIS (Netherlands)

    M. Visser (Mijke); D. Zubakov (Dmitry); K. Ballantyne (Kaye); M.H. Kayser (Manfred)

    2011-01-01

    textabstractAlthough the identification of human skin cells is of important relevance in many forensic cases, there is currently no reliable method available. Here, we present a highly specific and sensitive messenger RNA (mRNA) approach for skin identification, meeting the key requirements in

  1. Influenza virus mRNA trafficking through host nuclear speckles.

    Science.gov (United States)

    Mor, Amir; White, Alexander; Zhang, Ke; Thompson, Matthew; Esparza, Matthew; Muñoz-Moreno, Raquel; Koide, Kazunori; Lynch, Kristen W; García-Sastre, Adolfo; Fontoura, Beatriz M A

    2016-05-27

    Influenza A virus is a human pathogen with a genome composed of eight viral RNA segments that replicate in the nucleus. Two viral mRNAs are alternatively spliced. The unspliced M1 mRNA is translated into the matrix M1 protein, while the ion channel M2 protein is generated after alternative splicing. These proteins are critical mediators of viral trafficking and budding. We show that the influenza virus uses nuclear speckles to promote post-transcriptional splicing of its M1 mRNA. We assign previously unknown roles for the viral NS1 protein and cellular factors to an intranuclear trafficking pathway that targets the viral M1 mRNA to nuclear speckles, mediates splicing at these nuclear bodies and exports the spliced M2 mRNA from the nucleus. Given that nuclear speckles are storage sites for splicing factors, which leave these sites to splice cellular pre-mRNAs at transcribing genes, we reveal a functional subversion of nuclear speckles to promote viral gene expression.

  2. Somatic mutations of the RET proto-oncogene are not required for tumor development in multiple endocrine neoplasia type 2 (MEN 2) gene carriers

    NARCIS (Netherlands)

    Landsvater, RM; deWit, MJ; Zewald, RA; Hofstra, RMW; Buys, CHCM; vanAmstel, HKP; Hoppener, JWM; Lips, CJM

    1996-01-01

    Germ line mutations in one allele of the RET proto-oncogene predispose to the multiple endocrine neoplasia type 2 (MEN 2) syndromes, To investigate whether these inherited mutations alone can cause the development of tumors in vivo (oncogene model) or whether somatic mutations in the homologous RET

  3. Marek’s disease herpesvirus vaccines integrate into chicken host chromosomes yet lack a virus-host phenotype associated with oncogenic transformation

    Science.gov (United States)

    Marek's disease (MD) is a lymphotrophic and oncogenic disease of chickens that can lead to death in susceptible and unimmunized host birds. The causative pathogen, Marek's disease virus (MDV), a highly oncogenic alphaherpesvirus, integrates into host genome near the telomeres during viral latency an...

  4. The Agrobacterium rhizogenes oncogenes rolB and ORF13 increase formation of generative shoots and induce dwarfism in Arabidopsis thaliana (L.) Heynh

    DEFF Research Database (Denmark)

    Kodahl, Nete; Müller, Renate; Lütken, Henrik Vlk

    2016-01-01

    B oncogene yield plants with increased formation of generative shoots, but also result in some degree of premature senescence of vegetative organs. The extreme dwarfism seen in ORF13-lines indicate that this oncogene may be more important in the dwarfing response of plants transformed with the wild type Ri...

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

    NARCIS (Netherlands)

    DEVRIES, EGE; MULDER, NH

    1993-01-01

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

  6. The oncogene DEK promotes leukemic cell survival and is downregulated by both Nutlin-3 and chlorambucil in B-chronic lymphocytic leukemic cells.

    Science.gov (United States)

    Secchiero, Paola; Voltan, Rebecca; di Iasio, Maria Grazia; Melloni, Elisabetta; Tiribelli, Mario; Zauli, Giorgio

    2010-03-15

    To characterize the role of the oncogene DEK in modulating the response to either Nutlin-3, a small-molecule inhibitor of the MDM2/p53 interaction, or chlorambucil in primary B-chronic lymphocytic leukemia (B-CLL) cells. DEK mRNA and protein levels were evaluated in primary B-CLL samples (n = 21), p53(wild-type) SKW6.4, p53(mutated) BJAB lymphoblastoid cell lines, and normal CD19(+) B lymphocytes-treated Nutlin-3 or chlorambucil (10 micromol/L, each). Knocking down experiments with either p53 or DEK small interfering RNA (siRNA) were done to investigate the potential role of p53 in controlling the expression of DEK and the role of DEK in leukemic cell survival/apoptosis. Both Nutlin-3 and chlorambucil downregulated DEK in primary B-CLL samples (n = 21) and SKW6.4 but not in BJAB cells. Knocking down p53 attenuated the effect of Nutlin-3 on DEK expression, whereas knocking down DEK significantly increased both spontaneous and Nutlin-3-induced apoptosis. Conversely, counteracting DEK downmodulation by using p53 small interfering RNA reduced Nutlin-3-mediated apoptosis. On the other hand, Nutlin-3 potently induced p53 accumulation, but it did not affect DEK levels in normal CD19(+) B lymphocytes. These data show that the downregulation of DEK in response to either Nutlin-3 or chlorambucil represents an important molecular determinant in the cytotoxic response of leukemic cells, and suggest that strategies aimed to downregulate DEK might improve the therapeutic potential of these drugs.

  7. Activation of Wnt signaling pathway by human papillomavirus E6 and E7 oncogenes in HPV16-positive oropharyngeal squamous carcinoma cells.

    Science.gov (United States)

    Rampias, Theodore; Boutati, Eleni; Pectasides, Eirini; Sasaki, Clarence; Kountourakis, Panteleimon; Weinberger, Paul; Psyrri, Amanda

    2010-03-01

    We sought to determine the role of human papillomavirus (HPV) E6 and E7 oncogenes in nuclear beta-catenin accumulation, a hallmark of activated canonical Wnt signaling pathway. We used HPV16-positive oropharyngeal cancer cell lines 147T and 090, HPV-negative cell line 040T, and cervical cell lines SiHa (bearing integrated HPV16) and HeLa (bearing integrated HPV18) to measure the cytoplasmic and nuclear beta-catenin levels and the beta-catenin/Tcf transcriptional activity before and after E6/E7 gene silencing. Repression of HPV E6 and E7 genes induced a substantial reduction in nuclear beta-catenin levels. Luciferase assay showed that transcriptional activation of Tcf promoter by beta-catenin was lower after silencing. The protein levels of beta-catenin are tightly regulated by the ubiquitin/proteasome system. We therefore performed expression analysis of regulators of beta-catenin degradation and nuclear transport and showed that seven in absentia homologue (Siah-1) mRNA and protein levels were substantially upregulated after E6/E7 repression. Siah-1 protein promotes the degradation of beta-catenin through the ubiquitin/proteasome system. To determine whether Siah-1 is important for the proteasomal degradation of beta-catenin in HPV16-positive oropharyngeal cancer cells, we introduced a Siah-1 expression vector into 147T and 090 cells and found substantial reduction of endogenous beta-catenin in these cells. Thus, E6 and E7 are involved in beta-catenin nuclear accumulation and activation of Wnt signaling in HPV-induced cancers. In addition, we show the significance of the endogenous Siah-1-dependent ubiquitin/proteasome pathway for beta-catenin degradation and its regulation by E6/E7 viral oncoproteins in HPV16-positive oropharyngeal cancer cells.

  8. HPV16 oncogenes E6 or/and E7 may influence the methylation status of RASSFIA gene promoter region in cervical cancer cell line HT-3.

    Science.gov (United States)

    Yin, Fufen; Wang, Ning; Wang, Shanshan; Yu, Fengsheng; Sun, Xin; Yu, Xiao; Luo, Bing; Zhao, Chengquan; Wang, Yankui

    2017-04-01

    Both human papillomavirus (HPV) infection and the aberrant Ras associated domain family gene 1A (RASSF1A) promoter methylation status participate in the pathogenesis of cervical cancer. Some studies suggest that E6, and E7 are involved in the pathogenetic mechanisms of RASSF1A. We mainly explored a possible involvement of HPV16 oncogenes E6 or/and E7 in RASSF1A promoter methylation status and possible roles of RASSF1A gene methylation in cervical cancer. Bisulfite genomic sequencing (BGS) PCR combined with TA clone, methylation-specific PCR (MSP) were used to analyze methylation status of the RASSF1A gene promoter in HPV16/18-positive and HPV-negative cervical cancer cell lines; ectopically expressed HPV16 E6, E7 and E6/E7 cervical cancer cell lines; normal cervical and cervical cancer tissues. The mRNA and protein expression of RASSF1A was detected by RT-PCR and western blotting. Re-expression and downregulated promoter methylation status were detected in the ectopically expressed HPV16 E6 and E7 cervical cancer cell line HT-3. The methylation status and expression of RASSF1A could be downregulated or reactivated by 5-Aza-dc in HT-3 and C33A cells. Additionally, statistics showed significant hypermethylation of RASSF1A in cervical cancer samples compared to that in normal cervical samples (PE6 and/or E7 may be involved in aberrant methylation and expression of the RASSF1A gene. RASSF1A gene expression could be regulated by its promoter methylation status. Additionally, the false negativity of the HPV detection may contribute to the uncertain relationship between HPV infection and aberrant RASSF1A promoter methylation.

  9. Oncogenic kinase NPM/ALK induces through STAT3 expression of immunosuppressive protein CD274 (PD-L1, B7-H1).

    Science.gov (United States)

    Marzec, Michal; Zhang, Qian; Goradia, Ami; Raghunath, Puthiyaveettil N; Liu, Xiaobin; Paessler, Michele; Wang, Hong Yi; Wysocka, Maria; Cheng, Mangeng; Ruggeri, Bruce A; Wasik, Mariusz A

    2008-12-30

    The mechanisms of malignant cell transformation caused by the oncogenic, chimeric nucleophosmin (NPM)/anaplastic lymphoma kinase (ALK) remain only partially understood, with most of the previous studies focusing mainly on the impact of NPM/ALK on cell survival and proliferation. Here we report that the NPM/ALK-carrying T cell lymphoma (ALK+TCL) cells strongly express the immunosuppressive cell-surface protein CD274 (PD-L1, B7-H1), as determined on the mRNA and protein level. The CD274 expression is strictly dependent on the expression and enzymatic activity of NPM/ALK, as demonstrated by inhibition of the NPM/ALK function in ALK+TCL cells by the small molecule ALK inhibitor CEP-14083 and by documenting CD274 expression in IL-3-depleted BaF3 cells transfected with the wild-type NPM/ALK, but not the kinase-inactive NPM/ALK K210R mutant or empty vector alone. NPM/ALK induces CD274 expression by activating its key signal transmitter, transcription factor STAT3. STAT3 binds to the CD274 gene promoter in vitro and in vivo, as shown in the gel electromobility shift and chromatin immunoprecipitation assays, and is required for the PD-L1 gene expression, as demonstrated by siRNA-mediated STAT3 depletion. These findings identify an additional cell-transforming property of NPM/ALK and describe a direct link between an oncoprotein and an immunosuppressive cell-surface protein. These results also provide an additional rationale to therapeutically target NPM/ALK and STAT3 in ALK+TCL. Finally, they suggest that future immunotherapeutic protocols for this type of lymphoma may need to include the inhibition of NPM/ALK and STAT3 to achieve optimal clinical efficacy.

  10. Comprehensive analysis of HPV16 integration in OSCC reveals no significant impact of physical status on viral oncogene and virally disrupted human gene expression.

    Directory of Open Access Journals (Sweden)

    Nadine C Olthof

    Full Text Available Infection with high-risk human papillomavirus (HPV type 16 is an independent risk factor for the development of oropharyngeal squamous cell carcinomas (OSCC. However, it is unclear whether viral integration is an essential hallmark in the carcinogenic process of OSCC and whether HPV integration correlates with the level of viral gene transcription and influences the expression of disrupted host genes. We analyzed 75 patients with OSCC. HPV16-positivity was proven by p16(INK4A immunohistochemistry, PCR and FISH. Viral integration was examined using DIPS- as well as APOT-PCR. Viral E2, E6 and E7 gene expression levels were quantified by quantitative reverse transcriptase (RT-qPCR. Expression levels of 7 human genes disrupted by the virus were extracted from mRNA expression profiling data of 32 OSCCs. Viral copy numbers were assessed by qPCR in 73 tumors. We identified 37 HPV16-human fusion products indicating viral integration in 29 (39% OSCC. In the remaining tumors (61% only episome-derived PCR products were detected. When comparing OSCC with or without an integration-derived fusion product, we did not find significant differences in the mean RNA expression of viral genes E2, E6 and E7 or the viral copy numbers per cell, nor did the RNA expression of the HPV-disrupted genes differ from either group of OSCC. In conclusion, our data do not support the hypothesis that integration affects the levels of viral and/or HPV-disrupted human gene transcripts. Thus constitutive, rather than a high level, of expression of oncogene transcripts appears to be required in HPV-related OSCC.

  11. Pleiotropic Anti-Angiogenic and Anti-Oncogenic Activities of the Novel Mithralog Demycarosyl-3D-ß-D-Digitoxosyl-Mithramycin SK (EC-8042.

    Directory of Open Access Journals (Sweden)

    Azahara Fernández-Guizán

    Full Text Available Demycarosyl-3D-ß-D-digitoxosyl-mithramycin SK (DIG-MSK is a recently isolated analogue of mithramycin A (MTA that showed differences with MTA in the DNA binding strength and selectivity. These differences correlated with a better therapeutic index and less toxicity in animal studies. Herein, we show that DIG-MSK displays a potent anti-tumor activity against different types of cancer cell lines, ovarian tumor cells being particularly sensitive to this drug. Of relevance, DIG-MSK exerts low toxicity on fibroblasts and peripheral blood mononuclear cells, this toxicity being significantly lower than that of MTA. In correlation with its antitumor activity, DIG-MSK strongly inhibited Sp1-mediated transcription and endogenous Sp1 mRNA expression, which correlated with the inhibition of the expression of key Sp1-regulated genes involved in tumorigenesis, including VEGFA, BCL2L1 (Bcl-XL, hTERT, BRCA2, MYC and SRC in several ovarian cells. Significantly, DIG-MSK was a stronger inhibitor of VEGFA expression than MTA. Accordingly, DIG-MSK also exhibited potent anti-angiogenic activity on microvascular endothelial cells. Likewise, it significantly inhibited the gene expression of VEGFR1, VEGFR2, FGFR, PDGFB and PDGFRA and, additionally, it induced the expression of the anti-angiogenic factors angiostatin and tunstatin. These effects correlated with a pro-apoptotic effect on proliferating microvascular endothelial cells and the inhibition of the formation of endothelial capillary structures. Overall, the pleiotropic activity of DIG-MSK in inhibiting key oncogenic and angiogenic pathways, together with its low toxicity profile, highlight the therapeutic potential of this new drug.

  12. Dissection of the oncogenic MYCN transcriptional network reveals a large set of clinically relevant cell cycle genes as drivers of neuroblastoma tumorigenesis.

    Science.gov (United States)

    Murphy, Derek M; Buckley, Patrick G; Bryan, Kenneth; Watters, Karen M; Koster, Jan; van Sluis, Peter; Molenaar, Jan; Versteeg, Rogier; Stallings, Raymond L

    2011-06-01

    Amplification of the oncogenic transcription factor MYCN plays a major role in the pathogenesis of several pediatric cancers, including neuroblastoma, medulloblastoma, and rhabodomyosarcoma. For neuroblastoma, MYCN amplification is the most powerful genetic predictor of poor patient survival, yet the mechanism by which MYCN drives tumorigenesis is only partially understood. To gain an insight into the distribution of MYCN binding and to identify clinically relevant MYCN target genes, we performed an integrated analysis of MYCN ChIP-chip and mRNA expression using the MYCN repressible SHEP-21N neuroblastoma cell line. We hypothesized that genes exclusively MYCN bound in SHEP-21N cells over-expressing MYCN would be enriched for direct targets which contribute to the process of disease progression. Integrated analysis revealed that MYCN drives tumorigenesis predominantly as a positive regulator of target gene transcription. A high proportion of genes (24%) that are MYCN bound and up-regulated in the SHEP-21N model are significantly associated with poor overall patient survival (OS) in a set of 88 tumors. In contrast, the proportion of genes down-regulated when bound by MYCN in the SHEP-21N model and which are significantly associated with poor overall patient survival when under-expressed in primary tumors was significantly lower (5%). Gene ontology analysis determined a highly statistically significant enrichment for cell cycle related genes within the over-expressed MYCN target group which were also associated with poor OS. We conclude that the over-expression of MYCN leads to aberrant binding and over-expression of genes associated with cell cycle regulation which are significantly correlated with poor OS and MYCN amplification.

  13. FACTORES PRONOSTICOS DEL CANCER DE MAMA Y ONCOGEN HER2/NEU

    Directory of Open Access Journals (Sweden)

    F.J. Martín Gil

    2006-08-01

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

  14. Fatty Acid Synthase: A Metabolic Enzyme and Candidate Oncogene in Prostate Cancer

    Science.gov (United States)

    Migita, Toshiro; Ruiz, Stacey; Fornari, Alessandro; Fiorentino, Michelangelo; Priolo, Carmen; Zadra, Giorgia; Inazuka, Fumika; Grisanzio, Chiara; Palescandolo, Emanuele; Shin, Eyoung; Fiore, Christopher; Xie, Wanling; Kung, Andrew L.; Febbo, Phillip G.; Subramanian, Aravind; Mucci, Lorelei; Ma, Jing; Signoretti, Sabina; Stampfer, Meir; Hahn, William C.; Finn, Stephen

    2009-01-01

    Background Overexpression of the fatty acid synthase (FASN) gene has been implicated in prostate carcinogenesis. We sought to directly assess the oncogenic potential of FASN. Methods We used immortalized human prostate epithelial cells (iPrECs), androgen receptor–overexpressing iPrECs (AR-iPrEC), and human prostate adenocarcinoma LNCaP cells that stably overexpressed FASN for cell proliferation assays, soft agar assays, and tests of tumor formation in immunodeficient mice. Transgenic mice expressing FASN in the prostate were generated to assess the effects of FASN on prostate histology. Apoptosis was evaluated by Hoechst 33342 staining and by fluorescence-activated cell sorting in iPrEC-FASN cells treated with stimulators of the intrinsic and extrinsic pathways of apoptosis (ie, camptothecin and anti-Fas antibody, respectively) or with a small interfering RNA (siRNA) targeting FASN. FASN expression was compared with the apoptotic index assessed by the terminal deoxynucleotidyltransferase-mediated UTP end-labeling method in 745 human prostate cancer samples by using the least squares means procedure. All statistical tests were two-sided. Results Forced expression of FASN in iPrECs, AR-iPrECs, and LNCaP cells increased cell proliferation and soft agar growth. iPrECs that expressed both FASN and androgen receptor (AR) formed invasive adenocarcinomas in immunodeficient mice (12 of 14 mice injected formed tumors vs 0 of 14 mice injected with AR-iPrEC expressing empty vector (P < .001, Fisher exact test); however, iPrECs that expressed only FASN did not. Transgenic expression of FASN in mice resulted in prostate intraepithelial neoplasia, the incidence of which increased from 10% in 8- to 16-week-old mice to 44% in mice aged 7 months or more (P  = .0028, Fisher exact test), but not in invasive tumors. In LNCaP cells, siRNA-mediated silencing of FASN resulted in apoptosis. FASN overexpression protected iPrECs from apoptosis induced by camptothecin but did not

  15. Differential between Protein and mRNA Expression of CCR7 and SSTR5 Receptors in Crohn's Disease Patients

    Directory of Open Access Journals (Sweden)

    Nathalie Taquet

    2009-01-01

    Full Text Available Crohn's disease (CD is a multifactorial chronic inflammatory bowel disease of unknown cause. The aim of the present study was to explore if mRNA over-expression of SSTR5 and CCR7 found in CD patients could be correlated to respective protein expression. When compared to healthy donors, SSTR5 was over-expressed 417 ± 71 times in CD peripheral blood mononuclear cells (PBMCs. Flow cytometry experiments showed no correlation between mRNA and protein expression for SSTR5 in PBMCs. In an attempt to find a reason of such a high mRNA expression, SSTR5 present on CD PBMCs were tested and found as biologically active as on healthy cells. In biopsies of CD intestinal tissue, SSTR5 was not over-expressed but CCR7, unchanged in PBMCs, was over-expressed by 10 ± 3 times in the lamina propria. Confocal microscopy showed a good correlation of CCR7 mRNA and protein expression in CD intestinal biopsies. Our data emphasize flow and image cytometry as impossible to circumvent in complement to molecular biology so to avoid false interpretation on receptor expressions. Once confirmed by further large-scale studies, our preliminary results suggest a role for SSTR5 and CCR7 in CD pathogenesis.

  16. Convergent mutations and kinase fusions lead to oncogenic STAT3 activation in anaplastic large cell lymphoma.

    Science.gov (United States)

    Crescenzo, Ramona; Abate, Francesco; Lasorsa, Elena; Tabbo', Fabrizio; Gaudiano, Marcello; Chiesa, Nicoletta; Di Giacomo, Filomena; Spaccarotella, Elisa; Barbarossa, Luigi; Ercole, Elisabetta; Todaro, Maria; Boi, Michela; Acquaviva, Andrea; Ficarra, Elisa; Novero, Domenico; Rinaldi, Andrea; Tousseyn, Thomas; Rosenwald, Andreas; Kenner, Lukas; Cerroni, Lorenzo; Tzankov, Alexander; Ponzoni, Maurilio; Paulli, Marco; Weisenburger, Dennis; Chan, Wing C; Iqbal, Javeed; Piris, Miguel A; Zamo', Alberto; Ciardullo, Carmela; Rossi, Davide; Gaidano, Gianluca; Pileri, Stefano; Tiacci, Enrico; Falini, Brunangelo; Shultz, Leonard D; Mevellec, Laurence; Vialard, Jorge E; Piva, Roberto; Bertoni, Francesco; Rabadan, Raul; Inghirami, Giorgio

    2015-04-13

    A systematic characterization of the genetic alterations driving ALCLs has not been performed. By integrating massive sequencing strategies, we provide a comprehensive characterization of driver genetic alterations (somatic point mutations, copy number alterations, and gene fusions) in ALK(-) ALCLs. We identified activating mutations of JAK1 and/or STAT3 genes in ∼20% of 88 [corrected] ALK(-) ALCLs and demonstrated that 38% of systemic ALK(-) ALCLs displayed double lesions. Recurrent chimeras combining a transcription factor (NFkB2 or NCOR2) with a tyrosine kinase (ROS1 or TYK2) were also discovered in WT JAK1/STAT3 ALK(-) ALCL. All these aberrations lead to the constitutive activation of the JAK/STAT3 pathway, which was proved oncogenic. Consistently, JAK/STAT3 pathway inhibition impaired cell growth in vitro and in vivo.

  17. Neem Limonoids as Anticancer Agents: Modulation of Cancer Hallmarks and Oncogenic Signaling.

    Science.gov (United States)

    Nagini, Siddavaram

    2014-01-01

    Neem (Azadirachta indica A. Juss) is one of the most versatile medicinal plants, widely distributed in the Indian subcontinent. Neem is a rich source of limonoids that are endowed with potent medicinal properties predominantly antioxidant, anti-inflammatory, and anticancer activities. Azadirachtin, gedunin, and nimbolide are more extensively investigated relative to other neem limonoids. Accumulating evidence indicates that the anticancer effects of neem limonoids are mediated through the inhibition of hallmark capabilities of cancer such as cell proliferation, apoptosis evasion, inflammation, invasion, and angiogenesis. The neem limonoids have been demonstrated to target oncogenic signaling kinases and transcription factors chiefly, NF-κB, Wnt/β-catenin, PI3K/Akt, MAPK, and JAK/STAT signaling pathways. Neem limonoids that target multiple pathways that are aberrant in cancer are ideal candidates for cancer chemoprevention and therapy. © 2014 Elsevier Inc. All rights reserved.

  18. Oncogenic Alternative Splicing Switches: Role in Cancer Progression and Prospects for Therapy

    Directory of Open Access Journals (Sweden)

    Serena Bonomi

    2013-01-01

    Full Text Available Alterations in the abundance or activities of alternative splicing regulators generate alternatively spliced variants that contribute to multiple aspects of tumor establishment, progression and resistance to therapeutic treatments. Notably, many cancer-associated genes are regulated through alternative splicing suggesting a significant role of this post-transcriptional regulatory mechanism in the production of oncogenes and tumor suppressors. Thus, the study of alternative splicing in cancer might provide a better understanding of the malignant transformation and identify novel pathways that are uniquely relevant to tumorigenesis. Understanding the molecular underpinnings of cancer-associated alternative splicing isoforms will not only help to explain many fundamental hallmarks of cancer, but will also offer unprecedented opportunities to improve the efficacy of anti-cancer treatments.

  19. Oncogenic BRAF(V600E Induces Clastogenesis and UVB Hypersensitivity

    Directory of Open Access Journals (Sweden)

    Dennis A. Simpson

    2015-06-01

    Full Text Available The oncogenic BRAF(V600E mutation is common in melanomas as well as moles. The roles that this mutation plays in the early events in the development of melanoma are poorly understood. This study demonstrates that expression of BRAF(V600E is not only clastogenic, but synergizes for clastogenesis caused by exposure to ultraviolet radiation in the 300 to 320 nM (UVB range. Expression of BRAF(V600E was associated with induction of Chk1 pS280 and a reduction in chromatin remodeling factors BRG1 and BAF180. These alterations in the Chk1 signaling pathway and SWI/SNF chromatin remodeling pathway may contribute to the clastogenesis and UVB sensitivity. These results emphasize the importance of preventing sunburns in children with developing moles.

  20. The HPV E6/E7 Oncogenes: Key Factors for Viral Carcinogenesis and Therapeutic Targets.

    Science.gov (United States)

    Hoppe-Seyler, Karin; Bossler, Felicitas; Braun, Julia A; Herrmann, Anja L; Hoppe-Seyler, Felix

    2017-08-17

    Human papillomavirus (HPV)-induced cancers are expected to remain a major health problem worldwide for decades. The growth of HPV-positive cancer cells depends on the sustained expression of the viral E6 and E7 oncogenes which act in concert with still poorly defined cellular alterations. E6/E7 constitute attractive therapeutic targets since E6/E7 inhibition rapidly induces senescence in HPV-positive cancer cells. This cellular response is linked to the reconstitution of the antiproliferative p53 and pRb pathways, and to prosenescent mTOR signaling. Hypoxic HPV-positive cancer cells could be a major obstacle for treatment strategies targeting E6/E7 since they downregulate E6/E7 but evade senescence through hypoxia-induced mTOR impairment. Prospective E6/E7 inhibitors may therefore benefit from a combination with treatment strategies directed against hypoxic tumor cells. Copyright © 2017 Elsevier Ltd. All rights reserved.

  1. HOTAIR:an oncogenic long non-coding RNA in different cancers

    Institute of Scientific and Technical Information of China (English)

    Mohammadreza Hajjari; Abbas Salavaty

    2015-01-01

    Long non-coding RNAs (lncRNAs) refer to a group of RNAs that are usually more than 200 nucleotides and are not involved in protein generation. Instead, lncRNAs are involved in different regulatory processes, such as regulation of gene expression. Different lncRNAs exist throughout the genome. LncRNAs are also known for their roles in different human diseases such as cancer. HOTAIR is an lncRNA that plays a role as an oncogenic molecule in different cancer cells, such as breast, gastric, colorectal, and cervical cancer cells. Therefore, HOTAIR expression level is a potential biomarker for diagnostic and therapeutic purposes in several cancers. hTis RNA takes part in epigenetic regulation of genes and plays an important role in different cellular pathways by interacting with Polycomb Repressive Complex 2 (PRC2). In this review, we describe the molecular function and regulation of HOTAIR and its role in different types of cancers.

  2. The TRE17/USP6 oncogene: a riddle wrapped in a mystery inside an enigma.

    Science.gov (United States)

    Oliveira, Andre M; Chou, Margaret M

    2012-01-01

    De-ubiquitinating enzymes (DUBs) play critical roles in diverse cellular processes, including intracellular trafficking, protein turnover, inflammatory signaling, and cell transformation. The first DUB to be identified as an oncogene was TRE17/Ubiquitin-specific protease 6 (USP6)/Tre-2. In addition to encoding a USP, TRE17 also contains a TBC (Tre-2/Bub2/Cdc16) domain implicated in GTPase regulation and trafficking. Though first described almost two decades ago, remarkably little has been elucidated regarding TRE17's molecular and cellular functions. However, recent work has implicated TRE17 as a key etiological factor in aneurysmal bone cyst (ABC), a locally recurrent pediatric bone tumor, and identified potential pathways through which it acts. In this review, we discuss the most up-to-date findings on the molecular functions of TRE17, the role of its USP and TBC domains, and potential models for how it contributes to transformation and ABC pathogenesis.

  3. Dedifferentiation of neurons and astrocytes by oncogenes can induce gliomas in mice.

    Science.gov (United States)

    Friedmann-Morvinski, Dinorah; Bushong, Eric A; Ke, Eugene; Soda, Yasushi; Marumoto, Tomotoshi; Singer, Oded; Ellisman, Mark H; Verma, Inder M

    2012-11-23

    Glioblastoma multiforme (GBM) is the most common and aggressive malignant primary brain tumor in humans. Here we show that gliomas can originate from differentiated cells in the central nervous system (CNS), including cortical neurons. Transduction by oncogenic lentiviral vectors of neural stem cells (NSCs), astrocytes, or even mature neurons in the brains of mice can give rise to malignant gliomas. All the tumors, irrespective of the site of lentiviral vector injection (the initiating population), shared common features of high expression of stem or progenitor markers and low expression of differentiation markers. Microarray analysis revealed that tumors of astrocytic and neuronal origin match the mesenchymal GBM subtype. We propose that most differentiated cells in the CNS upon defined genetic alterations undergo dedifferentiation to generate a NSC or progenitor state to initiate and maintain the tumor progression, as well as to give rise to the heterogeneous populations observed in malignant gliomas.

  4. Genetic variations and alternative splicing. The Glioma associated oncogene 1, GLI1.

    Directory of Open Access Journals (Sweden)

    Peter eZaphiropoulos

    2012-07-01

    Full Text Available Alternative splicing is a post-transcriptional regulatory process that is attaining stronger recognition as a modulator of gene expression. Alternative splicing occurs when the primary RNA transcript is differentially processed into more than one mature RNAs. This is the result of a variable definition/inclusion of the exons, the sequences that are excised from the primary RNA to form the mature RNAs. Consequently, RNA expression can generate a collection of differentially spliced RNAs, which may distinctly influence subsequent biological events, such as protein synthesis or other biomolecular interactions. Still the mechanisms that control exon definition and exon inclusion are not fully clarified. This mini-review highlights advances in this field as well as the impact of single nucleotide polymorphisms in affecting splicing decisions. The Glioma associated oncogene 1, GLI1, is taken as an example in addressing the role of nucleotide substitutions for splicing regulation.

  5. [Advances Research on C-MYC Proto-oncogene in Multiple Myeloma -Review].

    Science.gov (United States)

    Huang, He; Guo, Wen-Jian; Yao, Ron-Xin

    2016-08-01

    Multiple myeloma(MM) as one of the most common tumors of hmatologic system, is characterized by malignant proliferation of plasma cells, and the chemotherapy is the main therapeutic method. MM is an incurable disease because of drug-resistance of MM cells. Although the pathogenesis of MM remains unknown, the chromosome abnormalities exit in half of the patients, particularly the highly expressed gene C-MYC. Furthermore, plenty of clinical researches indicated a high expression level of C-MYC implied worse progression and/or poor prognosis of MM. Recently, the work exploiting the compounds targeting MYC has made substantial progress, even in the MM therapy. In this article, briefly the recent advances of the research on C-MYC proto-oncogene in multiple myeloma are reviewed.

  6. No evidence for oncogenic mutations in the adrenocorticotropin receptor gene in human adrenocortical neoplasms

    Energy Technology Data Exchange (ETDEWEB)

    Latronico, A.C.; Reincke, M.; Mendonca, B.B. [National Inst. of Child Health and Human Development, Bethesda, MD (United States)] [and others

    1995-03-01

    The mechanism(s) of tumorigenesis for the majority of adrenocortical neoplasms remain unknown. G-Protein-coupled receptors were recently proposed as candidate protooncogenes. That activating mutations of this class of receptors might be important for tumor induction or progression of endocrine neoplasms was strengthened by the recent identification of such mutations in hyperfunctioning thyroid adenomas. To examine whether the ACTH receptor (ACTH-R) gene could be an oncogene in human adrenocortical tumors, we amplified by the polymerase chain reaction and directly sequenced the entire exon of the ACTH-R gene in 25 adrenocortical tumors (17 adenomas and 8 carcinomas) and 2 adrenocortical cancer cell lines. We found no missense point mutations or even silent polymorphisms in any of the tumors and cell lines studied. We conclude that activating mutations of the ACTH-R gene do not represent a frequent mechanism of human adrenocortical tumorigenesis. 15 refs., 2 tabs.

  7. Investigating the Expression of Oncogenic and Tumor Suppressive MicroRNA in DLBCL.

    Science.gov (United States)

    Handal, Brian; Enlow, Rossanna; Lara, Daniel; Bailey, Mark; Vega, Francisco; Hu, Peter; Lennon, Alan

    2013-01-01

    Diffuse Large B-cell Lymphoma (DLBCL) is the most common form of lymphoma, accounting for 40 percent of newly diagnosed cases each year. DLBCL is an aggressive abnormal growth of tissue characterized by the accumulation of abnormal B-lymphocytes in the lymphatics of affected individuals. The goal of this study was to analyze microRNA (miRNA) as an alternative method of diagnosis and treatment for patients affected with the observed cancer. MiRNAs are small, non-coding, endogenous RNA that control gene expression at the post-transcriptional level. Emerging evidence suggests that miRNA-mediated gene regulation has a functional role in cancer and could prove to be crucial targets for therapeutic intervention. Here, we provide a quantitative study on the expression of a diverse class of oncogenic and tumor suppressive miRNA that have shown to regulate oncoproteins involved in differentiation, proliferation, and/or apoptosis.

  8. [Diagnostic value of BRAFV600E and RET/PTC oncogenes in thyroid nodule aspirates].

    Science.gov (United States)

    Guerra, Anna; Carrano, Mario; Angrisani, Elisabetta; Vitale, Mario

    2013-01-01

    Fine-needle aspiration cytology (FNC) is the primary means to distinguish benign form malignant nodules. Aim of this study is to evaluate the diagnostic value of BRAF(V600E) and RET/PTC oncogenes in a large cohort of thyroid nodules with inconclusive FNC. We searched for BRAF(V600E) and RET/PTC in 299 thyroid nodule aspirates then removed by surgery. RET/PTC demonstrated a poor specificity. The search for BRAF(V600E) demonstrated to be useful in 25 cases, identifying a PTC in 2 false negative, 2 inadequate, 11 indeterminate and 10 suspicious FNC. Detection of BRAF(V600E) revealed to be a useful tool to refine inconclusive cytology.

  9. Oncogenic potential of Human Papillomavirus (HPV and its relation with cervical cancer

    Directory of Open Access Journals (Sweden)

    Idrees Muhammad

    2011-06-01

    Full Text Available Abstract Human Papillomavirus (HPV is the most common cause of cervical cancer. Cervical cancer being the second most common cancer after lung cancer, affecting women of different age groups; has a prevalence of about 20% in young sexually active women. Among different types of HPV, HPV16 the major strain causing this cancer and is sexually transmitted had been unnoticed for decades. Keeping in mind the multiple risk factors related with cervical cancer such as early age sexual activities, teenage pregnancies, smoking, use of oral contraceptives, having multiple sex partners, hormone replacement therapies and various other unknown factors lead to the onset of the disease. Awareness for various diagnostic procedures such as Pap smears screening prove to be an effective way in eradicating the oncogenic potential of HPV.

  10. Preliminary Study on c-Ha-ras Oncogene Mutations in Hydatidiform Mole Tissues

    Institute of Scientific and Technical Information of China (English)

    王芳; 谭运年; 陈碧; 李英勇; 康旭

    2001-01-01

    Objective To study the presence of c-Ha-fas oncogene mutations in hydatidiform mole (HM) tissues and to further explore its relationship with mole's malignancy Materials & methods c-Ha-ras codon 12 mutation was detected in invasive and noninvasive HM by using polymerase chain reaction (PCR) and restriction fragment length polymorphism (RFLP).Results c-Ha-fas codon 12 mutation was detected in 7 samples (53. 85%) of 13 invasive HM and 8 samples (26. 67%) in 30 non-invasive HM. c-Ha-ras mutations also showed loss of wild-type c-Ha-fas. No mutation in control group was observed.Conclusion The tendency of c-Ha-ras codon 12 mutation may be related with a higher invasive degree of HM.

  11. Genetic and pharmacological disruption of the TEAD-YAP complex suppresses the oncogenic activity of YAP.

    Science.gov (United States)

    Liu-Chittenden, Yi; Huang, Bo; Shim, Joong Sup; Chen, Qian; Lee, Se-Jin; Anders, Robert A; Liu, Jun O; Pan, Duojia

    2012-06-15

    The Drosophila TEAD ortholog Scalloped is required for Yki-mediated overgrowth but is largely dispensable for normal tissue growth, suggesting that its mammalian counterpart may be exploited for selective inhibition of oncogenic growth driven by YAP hyperactivation. Here we test this hypothesis genetically and pharmacologically. We show that a dominant-negative TEAD molecule does not perturb normal liver growth but potently suppresses hepatomegaly/tumorigenesis resulting from YAP overexpression or Neurofibromin 2 (NF2)/Merlin inactivation. We further identify verteporfin as a small molecule that inhibits TEAD-YAP association and YAP-induced liver overgrowth. These findings provide proof of principle that inhibiting TEAD-YAP interactions is a pharmacologically viable strategy against the YAP oncoprotein.

  12. Genetic and pharmacological disruption of the TEAD–YAP complex suppresses the oncogenic activity of YAP

    Science.gov (United States)

    Liu-Chittenden, Yi; Huang, Bo; Shim, Joong Sup; Chen, Qian; Lee, Se-Jin; Anders, Robert A.; Liu, Jun O.; Pan, Duojia

    2012-01-01

    The Drosophila TEAD ortholog Scalloped is required for Yki-mediated overgrowth but is largely dispensable for normal tissue growth, suggesting that its mammalian counterpart may be exploited for selective inhibition of oncogenic growth driven by YAP hyperactivation. Here we test this hypothesis genetically and pharmacologically. We show that a dominant-negative TEAD molecule does not perturb normal liver growth but potently suppresses hepatomegaly/tumorigenesis resulting from YAP overexpression or Neurofibromin 2 (NF2)/Merlin inactivation. We further identify verteporfin as a small molecule that inhibits TEAD–YAP association and YAP-induced liver overgrowth. These findings provide proof of principle that inhibiting TEAD–YAP interactions is a pharmacologically viable strategy against the YAP oncoprotein. PMID:22677547

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