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Cancer Genes (cancer + gene)
Terms modified by Cancer Genes Selected AbstractsBreast Cancer Genes and the Gendering of Knowledge: Science and Citizenship in the Cultural Context of the "New" Genetics by Sahra GibbonAMERICAN ANTHROPOLOGIST, Issue 1 2008JULIET M. MCMULLIN No abstract is available for this article. [source] Epigenetic changes in cancer,APMIS, Issue 10 2007KIRSTEN GRØNBÆK A cancer develops when a cell acquires specific growth advantages through the stepwise accumulation of heritable changes in gene function. Basically, this process is directed by changes in two different classes of genes: Tumor suppressor genes that inhibit cell growth and survival and oncogenes that promote cell growth and survival. Since several alterations are usually required for a cancer to fully develop, the malignant phenotype is determined by the compound status of tumor suppressor genes and oncogenes. Cancer genes may be changed by several mechanisms, which potentially alter the protein encoding nucleotide template, change the copy number of genes, or lead to increased gene transcription. Epigenetic alterations, which, by definition, comprise mitotically and meiotically heritable changes in gene expression that are not caused by changes in the primary DNA sequence, are increasingly being recognized for their roles in carcinogenesis. These epigenetic alterations may involve covalent modifications of amino acid residues in the histones around which the DNA is wrapped, and changes in the methylation status of cytosine bases (C) in the context of CpG dinucleotides within the DNA itself. Methylation of clusters of CpGs called "CpG-islands" in the promoters of genes has been associated with heritable gene silencing. The present review will focus on how disruption of the epigenome can contribute to cancer. In contrast to genetic alterations, gene silencing by epigenetic modifications is potentially reversible. Treatment by agents that inhibit cytosine methylation and histone deacetylation can initiate chromatin decondensation, demethylation and reestablishment of gene transcription. Accordingly, in the clinical setting, DNA methylation and histone modifications are very attractive targets for the development and implementation of new therapeutic approaches. Many clinical trials are ongoing, and epigenetic therapy has recently been approved by the United States Food and Drug Administration (US FDA) for use in the treatment of myelodysplastic syndrome (MDS) and primary cutaneous T-cell lymphoma (CTCL). [source] Genome-wide scan identifies a copy number variable region at 3q26 that regulates PPM1L in APC mutation-negative familial colorectal cancer patientsGENES, CHROMOSOMES AND CANCER, Issue 2 2010L. F. Thean Familial adenomatous polyposis (FAP) is an autosomal dominantly inherited form of colorectal cancer (CRC) caused by mutation in the adenomatous polyposis coli (APC) gene. However, APC mutations are not detected in 10,50% of FAP patients. We searched for a new cancer gene by performing genome-wide genotyping on members of an APC mutation-negative FAP variant family and ethnicity-matched healthy controls. No common copy number change was found in all affected members using the unaffected members and healthy controls as baseline. A 111 kb copy number variable (CNV) region at 3q26.1 was shown to have copy number loss in all eight polyps compared to matched lymphocytes of two affected members. A common region of loss in all polyps, which are precursors to CRC, is likely to harbor disease-causing gene in accordance to Knudsen's "two-hit" hypothesis. There is, however, no gene within the deleted region. A 2-Mb scan of the genomic region encompassing the deleted region identified PPM1L, coding for a novel serine-threonine phosphatase in the TGF-, and BMP signaling pathways. Real-time PCR analyses indicate that the 3,UTR of PPM1L transcript was down-regulated more than two-folds in all six polyps and tumors compared to matched mucosa of the affected member. This down-regulation was not observed in APC mutation-positive FAP patients. Our results suggest that the CNV region at 3q26 harbors an element that regulates the expression of an upstream candidate tumor suppressor, PPM1L, thus providing a novel mechanism for colorectal tumorigenesis in APC mutation-negative familial CRC patients. © 2009 Wiley-Liss, Inc. [source] Over-expression of I,B-kinase-, (IKK,/IKKi) induces secretion of inflammatory cytokines in prostate cancer cell linesTHE PROSTATE, Issue 7 2009Benjamin Péant Abstract BACKGROUND Elevated inflammatory cytokine levels in serum have been associated with advanced stage metastasis-related morbidity in prostate cancer. Several studies have shown that IL-6 and IL-8 can accelerate the growth of human prostate cancer cell lines. Previous studies, in murine embryonic fibroblasts, have shown that I,-B kinase-epsilon (IKK,/IKKi)-deficiency results in the reduction of lipopolysaccharide-mediated expression of IL-6. RESULTS In this study, we report that over-expression of IKK, in hormone-sensitive 22Rv1 and LNCaP prostate cancer cells induces the secretion of several inflammatory cytokines including IL-6 and IL-8. Both of these cytokines are secreted by hormone-refractory PC-3 prostate cancer cells and IKK, knock-down in these cells correlates with a strong decrease in IL-6 secretion. Furthermore, we demonstrate that IKK, over-expression does not induce the activation of the IKK, classical targets NF-,B and IRF-3, two transcription factors involved in the regulation of several cytokines. Finally, we observe that high IKK, expression results in its nuclear translocation, a phenomena that is TBK1-independent. CONCLUSIONS This study identifies IKK, as a potential prostate cancer gene that may favor chronic inflammation and create a tumor-supporting microenvironment that promotes prostate cancer progression, particularly by the induction of IL-6 secretion that may act as a positive growth factor in prostate cancer. Prostate 69: 706,718, 2009. © 2009 Wiley-Liss, Inc. [source] Renal carcinogenesis: Genotype, phenotype and dramatypeCANCER SCIENCE, Issue 2 2003Okio Hino Cancer is a heritable disorder of somatic cells. Environment and heredity are both important in the carcinogenic process. The Eker rat model of hereditary renal carcinoma (RC) is an example of a Mendelian dominantly inherited predisposition to a specific cancer in an experimental animal. Forty years after the discovery of the Eker rat in Oslo, we and Knudson's group independently identified a germline retrotransposon insertion in the rat homologue of the human tuberous sclerosis (TSC2) gene. To our knowledge, this was the first isolation of a Mendelian dominantly predisposing cancer gene in a naturally occurring animal model. Recently, we discovered a new hereditary renal carcinoma in the rat. This rat was named the "Ninon''rat and its predisposing (Nihon) gene could be a novel renal tumor suppressor gene. This article will review the utility of these unique models for the study of problems in carcinogenesis; e.g., species-specific differences in tumorigenesis, cell stage and tissue/cell-type specific tumorigene-sis, multistep carcinogenesis, modifier gene(s) in renal carcinogenesis, cancer prevention and the development of therapeutic treatments which can be translated to human patients, as well as how environmental factors interact with cancer susceptibility gene(s). (Cancer Sci 2003; 94: 142,147) [source] Sympathectomy suppresses tumor growth and alters gene-expression profiles in rat tongue cancerEUROPEAN JOURNAL OF ORAL SCIENCES, Issue 4 2009Bina Raju Sympathetic nerves are known to affect carcinogenesis. Recently we found that sympathetic denervation decreases the size of rat tongue tumors. To identify genes involved in rat tongue carcinogenesis and to study the effect of sympathetic nerves on these genes, we compared gene-expression profiles in normal rat tongue (control) and in tumor-induced tongues with (SCGx) and without (Sham) bilateral sympathectomy. Significance analysis of microarrays revealed 280 genes (168 up-regulated, 112 down-regulated) that showed at least a twofold differential expression between Sham and SCGx tumors (false discovery rate < 5%). These included genes associated with cell adhesion, signaling, structure, proliferation, metabolism, angiogenesis, development, and immunity. Hierarchical clustering demonstrated that controls and sympathectomized tumors grouped together, while Sham tumors grouped separately. We identified 34 genes, known to be involved in carcinogenesis, that were not differentially expressed between sympathectomized tumors and control tongues, but which showed a significant change in expression in Sham tumors. Microarray results of 12 of these genes were confirmed by quantitative reverse transcription,polymerase chain reaction. In conclusion, sympathectomy significantly altered the gene-expression profile and inhibited tumor growth. The expression of several cancer genes were increased more than threefold in Sham tumors, but unaltered in the sympathectomized tumors when compared with controls, indicating that these genes may be of significance in rat tongue carcinogenesis. [source] Integrative approach for prioritizing cancer genes in sporadic colon cancer,GENES, CHROMOSOMES AND CANCER, Issue 11 2009James F. Reid The current multistep carcinogenesis models of colon cancer do not fully capture the genetic heterogeneity of the disease, which is additionally complicated by the presence of passenger and driver genetic alterations. The aim of this study was to select in the context of this significant heterogeneity additional genes functionally related to colon cancer development. High-throughput copy number and gene expression data of 36 microsatellite stable sporadic colon cancers resected from patients of a single institution characterized for mutations in APC, KRAS, TP53 and loss of 18q were analyzed. Genes whose expression correlated with the underlying copy number pattern were selected, and their association with the above listed mutations and overall survival was evaluated. Gain of 20q was strongly associated with TP53 mutation, and overall survival with alterations on 7p, 8p, 13q, 18q, and 20q. An association with 18q loss and gain of 8q24 was also observed. New candidate genes with a potential role in colon cancer are PLCG1 on 20q, DBC1 on 8q21, and NDGR1 on 8p24. In addition, an unexpected pattern of loss and mutability was found in the region upstream of the KRAS gene. By integrating copy number alterations with gene expression and mutations in colon cancer associated genes, we have developed a strategy that identifies previously known molecular features and additional players in the molecular landscape of colon cancer. © 2009 Wiley-Liss, Inc. [source] Genetic testing for cancer predisposition and implications for nursing practice: narrative reviewJOURNAL OF ADVANCED NURSING, Issue 4 2010Elizabeth Kathryn Bancroft bancroft e.k. (2010) Genetic testing for cancer predisposition and implications for nursing practice: narrative review. Journal of Advanced Nursing66(4), 710,737. Abstract Title.,Genetic testing for cancer predisposition and implications for nursing practice:narrative review. Aim., This paper is a report of a review of literature on the psychological and social implications of genetic testing for cancer predisposition and how recent developments in knowledge about genetics may affect clinical practice. Background., Knowledge about the genetics of disease has grown since the completion of the Human Genome Project. Many common genetic changes that predispose to cancer have been found. Identifying genetically ,at risk' individuals is going to become a feature of healthcare and nursing practice over the next decade. The psychological and social effects of this knowledge on patients and their families are important considerations. Data sources., A search of the British Nursing Index, CINAHL, EMBASE and PUBMED databases was conducted between June 2007 and December 2008 without date limits. Grey literature was sought using search engines and through searching relevant websites. Review methods., A narrative review of studies published in English was conducted. The studies were reviewed for relevance and inclusion criteria; their methodological quality was not evaluated. Results., Seventy-eight papers met the inclusion criteria and fell into three thematic categories: social impact, psychological impact and interest in and uptake of genetic testing. To date, research has focussed on high-risk cancer genes. Conclusion., Genetic testing raises social, ethical and psychological concerns. Further research is required to determine how healthcare professionals can support the integration of genetics into clinical practice. Nurses will become increasingly involved in genetic testing and will play a key role in providing information, support and follow-up for individuals identified as being at higher risk. [source] Molecular aspects of diagnostic nucleolar and nuclear envelope changes in prostate cancerJOURNAL OF CELLULAR BIOCHEMISTRY, Issue 1 2004Andrew H. Fischer Abstract Prostate cancer is still diagnosed by pathologists based on subjective assessment of altered cell and tissue structure. The cellular-level structural changes diagnostic of some forms of cancer are known to be induced by cancer genes, but the relation between specific cellular-level structural features and cancer genes has not been explored in the prostate. Two important cell structural changes in prostate cancer,nucleolar enlargement and nuclear envelope (NE) irregularity,are discussed from the perspective that they should also relate to the function of the genes active in prostate cancer. Enlargement of the nucleolus is the key diagnostic feature of high-grade prostatic intraepithelial neoplasia (PIN), an early stage that appears to be the precursor to the majority of invasive prostate cancers. Nucleolar enlargement classically is associated with increased ribosome production, and production of new ribosomes appears essential for cell-cycle progression. Several cancer genes implicated in PIN are known (in other cell types) to augment ribosome production, including c-Myc, p27, retinoblastoma, p53, and growth factors that impact on ERK signaling. However, critical review of the available information suggests that increased ribosome production per se may be insufficient to explain nucleolar enlargement in PIN, and other newer functions of nucleoli may therefore need to be invoked. NE irregularity develops later in the clonal evolution of some prostate cancers, and it has adverse prognostic significance. Nuclear irregularity has recently been shown to develop dynamically during interphase following oncogene expression, without a requirement for post-mitotic NE reassembly. NE irregularity characteristic of some aggressive prostate cancers could reflect cytoskeletal forces exerted on the NE during active cell locomotion. NE irregularity could also promote chromosomal instability because it leads to chromosomal asymmetry in metaphase. Finally, NE irregularity could impact replication competence, transcriptional programming and nuclear pore function. © 2003 Wiley-Liss, Inc. [source] Ubiquitous cancer genes: Multipurpose molecules for protein micro-arraysPROTEINS: STRUCTURE, FUNCTION AND BIOINFORMATICS, Issue 1 2006Brigitte Altenberg Abstract Multipurpose genes in the human genome which are over-expressed in a large variety of different cancers have been identified. Forty-two of the 19,016,human genes annotated to date (0.2%) are ubiquitously over-expressed in half or more of the 36,investigated human cancers. Of these genes, 15,are involved in protein biosynthesis and folding, six of them in glycolysis. A group of 13,solid tumours over-express almost all (39,42 of 42) ubiquitous cancer genes, suggesting a common mechanism underlying these cancers. Others, such as endocrine cancers, have only a few over-expressed ubiquitous cancer genes. The proteins for which these genes code or the corresponding antibodies are candidates for small protein microarrays aiming at maximum information with only a limited number of proteins. Since the over-expression pattern varies from cancer to cancer, distinction between different cancer classes is possible using one single set of protein or antibody molecules. [source] Communication and decision-making about seeking inherited cancer risk information: findings from female survivor-relative focus groupsPSYCHO-ONCOLOGY, Issue 3 2006Suzanne Mellon Abstract Dramatic advances in cancer genetics and identification of germline mutations in cancer genes such as BRCA1 and BRCA2 have led to new options in genetic risk assessment for families with histories of breast and ovarian cancer. However, little research has been carried out with individuals and their families regarding how cancer risk information is communicated within families and factors that may affect individuals and family members making informed decisions about their health. This study explored participants' knowledge of cancer risk, their perceptions and concerns regarding inherited cancer risk information, family communication patterns, and factors that may affect their decision to learn about inherited cancer risk in their families. Nine focus groups of family dyads were conducted (N=39) consisting of breast or ovarian cancer patients and close female relatives. All transcribed interviews were analyzed using qualitative software. Key findings showed diversity in how families communicated and made decisions about their health, persistent worry for their families, lack of knowledge about inherited cancer, vigilance in watching their health, and barriers present in communicating about genetic risk. Results from this study support inclusion of family members in addressing inherited cancer risk information and contextual family factors critical to consider in potentially high risk families. Copyright © 2005 John Wiley & Sons, Ltd. [source] Analysis of BRCA1 and BRCA2 in breast and breast/ovarian cancer families shows population substructure in the Iberian peninsulaANNALS OF HUMAN GENETICS, Issue 1 2002A. VEGA An estimated 5,10% of all breast and ovarian cancers are due to an inherited predisposition, representing a rather large number of patients. In Spain 1/13,1/14 women will be diagnosed with breast cancer during their lifetime. Two major breast cancer genes, BRCA1 and BRCA2, have been identified. To date, several hundred pathogenic mutations in these two genes have been published or reported to the Breast Cancer Information Core, BIC database (http://www.nhgri.nih.gov/Intramural_research_Labtransfer/Bic/index.html). In the present study, 30 Spanish breast and breast/ovarian cancer families (29 from Galicia, NW Spain, and 1 from Catalonia, NE Spain) were screened for mutations in the BRCA1 and BRCA2 genes. The analysis of these genes was carried out by SSCP for shorter exons and direct sequencing in the case of longer ones. Mutations were found in 8 of the 30 families studied (26.66%). It is important to note that all mutations were detected within the BRCA1 gene: 330 A>G, 910_913delGTTC, 2121 C>T, 3958_3962delCTCAGinsAGGC, and 5530 T>A. The BRCA1 330 A>G mutation was found in four unrelated families and accounted for 50% of all identified mutations. [source] | |||||||||||||