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Sample records for brca1 tp53 nm-23

  1. High incidence of protein-truncating TP53 mutations in BRCA1-related breast cancer.

    Science.gov (United States)

    Holstege, Henne; Joosse, Simon A; van Oostrom, Conny Th M; Nederlof, Petra M; de Vries, Annemieke; Jonkers, Jos

    2009-04-15

    Approximately half of all hereditary breast cancers are compromised in their DNA repair mechanisms due to loss of BRCA1 or BRCA2 function. Previous research has found a strong correlation between BRCA mutation and TP53 mutation. However, TP53 mutation status is often indirectly assessed by immunohistochemical staining of accumulated p53 protein. We sequenced TP53 exons 2 to 9 in 21 BRCA1-related breast cancers and 37 sporadic breast tumors. Strikingly, all BRCA1-related breast tumors contained TP53 mutations, whereas only half of these tumors stained positive for p53 accumulation. Positive p53 staining correlates with the presence of TP53 hotspot mutations in both BRCA1-related and sporadic breast tumors. However, whereas the majority of sporadic breast tumors that stained negative for p53 accumulation had wild-type TP53, the majority of BRCA1-associated breast tumors that stained negative for p53 accumulation had protein-truncating TP53 mutations (nonsense, frameshift, and splice mutations). Therefore, the strong selection for p53 loss in BRCA1-related tumors is achieved by an increase of protein-truncating TP53 mutations rather than hotspot mutations. Hence, immunohistochemical detection of TP53 mutation could lead to misdiagnosis in approximately half of all BRCA1-related tumors. The presence of deleterious TP53 mutations in most, if not all, BRCA1-related breast cancers suggests that p53 loss of function is essential for BRCA1-associated tumorigenesis. BRCA1-related tumors may therefore be treated not only with drugs that target BRCA1 deficiency [e.g., poly(ADP-ribose) polymerase inhibitors] but also with drugs that selectively target p53-deficient cells. This raises interesting possibilities for combination therapies against BRCA1-deficient breast cancers and BRCA1-like tumors with homologous recombination deficiency.

  2. BRCA1-mutated and basal-like breast cancers have similar aCGH profiles and a high incidence of protein truncating TP53 mutations

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    van de Vijver Marc J

    2010-11-01

    Full Text Available Abstract Background Basal-like breast cancers (BLBC are aggressive breast cancers for which, so far, no targeted therapy is available because they typically lack expression of hormone receptors and HER2. Phenotypic features of BLBCs, such as clinical presentation and early age of onset, resemble those of breast tumors from BRCA1-mutation carriers. The genomic instability of BRCA1-mutated tumors can be effectively targeted with DNA-damaging agents and poly-(ADP-ribose polymerase 1 (PARP1 inhibitors. Molecular similarities between BLBCs and BRCA1-mutated tumors may therefore provide predictive markers for therapeutic response of BLBCs. Methods There are several known molecular features characteristic for BRCA1-mutated breast tumors: 1 increased numbers of genomic aberrations, 2 a distinct pattern of genomic aberrations, 3 a high frequency of TP53 mutations and 4 a high incidence of complex, protein-truncating TP53 mutations. We compared the frequency of TP53 mutations and the pattern and amount of genomic aberrations between BRCA1-mutated breast tumors, BLBCs and luminal breast tumors by TP53 gene sequencing and array-based comparative genomics hybridization (aCGH analysis. Results We found that the high incidence of protein truncating TP53 mutations and the pattern and amount of genomic aberrations specific for BRCA1-mutated breast tumors are also characteristic for BLBCs and different from luminal breast tumors. Conclusions Complex, protein truncating TP53 mutations in BRCA1-mutated tumors may be a direct consequence of genomic instability caused by BRCA1 loss, therefore, the presence of these types of TP53 mutations in sporadic BLBCs might be a hallmark of BRCAness and a potential biomarker for sensitivity to PARP inhibition. Also, our data suggest that a small subset of genomic regions may be used to identify BRCA1-like BLBCs. BLBCs share molecular features that were previously found to be specific for BRCA1-mutated breast tumors. These

  3. BRCA1-mutated and basal-like breast cancers have similar aCGH profiles and a high incidence of protein truncating TP53 mutations.

    Science.gov (United States)

    Holstege, Henne; Horlings, Hugo M; Velds, Arno; Langerød, Anita; Børresen-Dale, Anne-Lise; van de Vijver, Marc J; Nederlof, Petra M; Jonkers, Jos

    2010-11-30

    Basal-like breast cancers (BLBC) are aggressive breast cancers for which, so far, no targeted therapy is available because they typically lack expression of hormone receptors and HER2. Phenotypic features of BLBCs, such as clinical presentation and early age of onset, resemble those of breast tumors from BRCA1-mutation carriers. The genomic instability of BRCA1-mutated tumors can be effectively targeted with DNA-damaging agents and poly-(ADP-ribose) polymerase 1 (PARP1) inhibitors. Molecular similarities between BLBCs and BRCA1-mutated tumors may therefore provide predictive markers for therapeutic response of BLBCs. There are several known molecular features characteristic for BRCA1-mutated breast tumors: 1) increased numbers of genomic aberrations, 2) a distinct pattern of genomic aberrations, 3) a high frequency of TP53 mutations and 4) a high incidence of complex, protein-truncating TP53 mutations. We compared the frequency of TP53 mutations and the pattern and amount of genomic aberrations between BRCA1-mutated breast tumors, BLBCs and luminal breast tumors by TP53 gene sequencing and array-based comparative genomics hybridization (aCGH) analysis. We found that the high incidence of protein truncating TP53 mutations and the pattern and amount of genomic aberrations specific for BRCA1-mutated breast tumors are also characteristic for BLBCs and different from luminal breast tumors. Complex, protein truncating TP53 mutations in BRCA1-mutated tumors may be a direct consequence of genomic instability caused by BRCA1 loss, therefore, the presence of these types of TP53 mutations in sporadic BLBCs might be a hallmark of BRCAness and a potential biomarker for sensitivity to PARP inhibition. Also, our data suggest that a small subset of genomic regions may be used to identify BRCA1-like BLBCs. BLBCs share molecular features that were previously found to be specific for BRCA1-mutated breast tumors. These features might be useful for the identification of tumors with

  4. Comprehensive analysis of BRCA1, BRCA2 and TP53 germline mutation and tumor characterization: a portrait of early-onset breast cancer in Brazil.

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    Dirce Maria Carraro

    Full Text Available Germline mutations in BRCA1, BRCA2 and TP53 genes have been identified as one of the most important disease-causing issues in young breast cancer patients worldwide. The specific defective biological processes that trigger germline mutation-associated and -negative tumors remain unclear. To delineate an initial portrait of Brazilian early-onset breast cancer, we performed an investigation combining both germline and tumor analysis. Germline screening of the BRCA1, BRCA2, CHEK2 (c.1100delC and TP53 genes was performed in 54 unrelated patients <35 y; their tumors were investigated with respect to transcriptional and genomic profiles as well as hormonal receptors and HER2 expression/amplification. Germline mutations were detected in 12 out of 54 patients (22% [7 in BRCA1 (13%, 4 in BRCA2 (7% and one in TP53 (2% gene]. A cancer familial history was present in 31.4% of the unrelated patients, from them 43.7% were carriers for germline mutation (37.5% in BRCA1 and in 6.2% in the BRCA2 genes. Fifty percent of the unrelated patients with hormone receptor-negative tumors carried BRCA1 mutations, percentage increasing to 83% in cases with familial history of cancer. Over-representation of DNA damage-, cellular and cell cycle-related processes was detected in the up-regulated genes of BRCA1/2-associated tumors, whereas cell and embryo development-related processes were over-represented in the up-regulated genes of BRCA1/2-negative tumors, suggesting distinct mechanisms driving the tumorigenesis. An initial portrait of the early-onset breast cancer patients in Brazil was generated pointing out that hormone receptor-negative tumors and positive familial history are two major risk factors for detection of a BRCA1 germline mutation. Additionally, the data revealed molecular factors that potentially trigger the tumor development in young patients.

  5. Germ-line TP53 mutations in Finnish cancer families exhibiting features of the Li-Fraumeni syndrome and negative for BRCA1 and BRCA2.

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    Huusko, P; Castrén, K; Launonen, V; Soini, Y; Pääkkönen, K; Leisti, J; Vähäkangas, K; Winqvist, R

    1999-07-01

    Mutations in BRCA1 and BRCA2 account for a large portion of the inherited predisposition to breast and ovarian cancer. It was recently discovered that mutations in these two genes are less common in the Finnish population than expected. Because the genetic background of breast cancer, in particular, is largely obscure, it became necessary to search for mutations in other susceptibility genes. Because seven of our BRCA1 and BRCA2 mutation-negative families fulfilled the criteria of either Li-Fraumeni syndrome (LFS) or Li-Fraumeni-like syndrome (LFL), we decided to screen them for germ-line TP53 mutations in exons 5-8 using a dual-temperature single-strand conformation polymorphism assay (SSCP). Two missense mutations (Asn235Ser and Tyr220Cys) were identified. The clinical significance of these findings was evaluated by comparison to previously reported germ-line TP53 mutation data, and by using the tumor loss of heterozygosity (LOH) analysis. In addition, an immunohistochemical analysis of tumor specimens from mutation-positive individuals was performed. Our results suggest that the observed missense mutations confer susceptibility to cancer, and that germ-line TP53 mutations would therefore explain an additional fraction of hereditary breast cancer in Finland.

  6. Screening for germline BRCA1, BRCA2, TP53 and CHEK2 mutations in families at-risk for hereditary breast cancer identified in a population-based study from Southern Brazil

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    Edenir Inêz Palmero

    2016-01-01

    Full Text Available Abstract In Brazil, breast cancer is a public health care problem due to its high incidence and mortality rates. In this study, we investigated the prevalence of hereditary breast cancer syndromes (HBCS in a population-based cohort in Brazils southernmost capital, Porto Alegre. All participants answered a questionnaire about family history (FH of breast, ovarian and colorectal cancer and those with a positive FH were invited for genetic cancer risk assessment (GCRA. If pedigree analysis was suggestive of HBCS, genetic testing of the BRCA1, BRCA2, TP53, and CHEK2 genes was offered. Of 902 women submitted to GCRA, 214 had pedigrees suggestive of HBCS. Fifty of them underwent genetic testing: 18 and 40 for BRCA1/BRCA2 and TP53 mutation screening, respectively, and 7 for CHEK2 1100delC testing. A deleterious BRCA2 mutation was identified in one of the HBOC probands and the CHEK2 1100delC mutation occurred in one of the HBCC families. No deleterious germline alterations were identified in BRCA1 or TP53. Although strict inclusion criteria and a comprehensive testing approach were used, the suspected genetic risk in these families remains unexplained. Further studies in a larger cohort are necessary to better understand the genetic component of hereditary breast cancer in Southern Brazil.

  7. Routine TP53 testing for breast cancer under age 30: ready for prime time?

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    McCuaig, Jeanna M; Armel, Susan R; Novokmet, Ana; Ginsburg, Ophira M; Demsky, Rochelle; Narod, Steven A; Malkin, David

    2012-12-01

    It is well known that early-onset breast cancer may be due to an inherited predisposition. When evaluating women diagnosed with breast cancer under age 30, two important syndromes are typically considered: Hereditary Breast and Ovarian Cancer Syndrome and Li-Fraumeni syndrome. Many women are offered genetic testing for mutations in the BRCA1 and BRCA2 genes; however, few are offered genetic testing for mutations in the TP53 gene. There is a concern that overly restrictive testing of TP53 may fail to recognize families with Li-Fraumeni syndrome. We reviewed the genetic test results and family histories of all women with early-onset breast cancer who had genetic testing of the TP53 gene at the Toronto Hospital for Sick Children. Of the 28 women tested, six (33.3 %) had a mutation in the TP53 gene; a mutation was found in 7.7 % of women who did not meet current criteria for Li-Fraumeni syndrome. By reviewing similar data published between 2000 and 2011, we estimate that 5-8 % of women diagnosed with early-onset breast cancer, and who have a negative family history, may have a mutation in the TP53 gene. Given the potential benefits versus harms of this testing, we discuss the option of simultaneous testing of all three genes (BRCA1, BRCA2, and TP53) for women diagnosed with breast cancer before age 30.

  8. A novel HER2-positive breast cancer phenotype arising from germline TP53 mutations.

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    Wilson, J R F; Bateman, A C; Hanson, H; An, Q; Evans, G; Rahman, N; Jones, J L; Eccles, D M

    2010-11-01

    The Li-Fraumeni Syndrome is caused by a germline TP53 mutation and is associated with a high risk of breast cancer at young ages. Basal (triple negative) breast cancers are now well recognised to be a typical sub-type of breast cancer developing in a large proportion of BRCA1 gene carriers. We considered whether a similar narrow sub-type of breast cancer was found in TP53 gene mutation carriers. A hypothesis generating study to investigate whether there are specific breast tumour characteristics associated with germline TP53 mutations. Pathological characteristics in 12 breast cancers arising in nine patients carrying pathogenic TP53 mutations were compared to a reference panel of 231 young onset breast tumours included in the POSH study. Patients carrying a TP53 mutation showed a significantly higher likelihood of developing a breast cancer with Human Epidermal growth factor Receptor (HER2) amplification (83%) when compared to the cohort of young onset breast cancer cases (16%); ER and PR status were equivalent between groups. These findings suggest that breast cancer developing on a background of an inherited TP53 mutation is highly likely to present with amplification of HER2.

  9. Family history and BRCA1/BRCA2 status among Japanese ovarian cancer patients and occult cancer in a BRCA1 mutant case.

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    Hirasawa, Akira; Masuda, Kenta; Akahane, Tomoko; Ueki, Arisa; Yokota, Megumi; Tsuruta, Tomohiko; Nomura, Hiroyuki; Kataoka, Fumio; Tominaga, Eiichiro; Banno, Kouji; Makita, Kazuya; Susumu, Nobuyuki; Sugano, Kokichi; Kosaki, Kenjiro; Kameyama, Kaori; Aoki, Daisuke

    2014-01-01

    This study aimed to examine family history among Japanese ovarian cancer patients and to investigate the TP53 status of fallopian tube epithelial and ovarian cancer cells in a Japanese BRCA1 mutant case that may be associated with the transformed state in hereditary ovarian cancer. One hundred and two primary ovarian cancer patients were retrospectively evaluated in this cross-sectional study. The family history of cancer was determined in probands. In a BRCA1 mutant case, p53 immunostaining and direct sequencing, followed by laser-capture microdissection, were performed for the fallopian tube, considered the origin of ovarian cancer. Nine of 102 (8.8%) families were regarded as having hereditary breast-ovarian cancer syndrome, two families (2.0%) were diagnosed with Lynch syndrome and six patients harbored BRCA1 or BRCA2 mutations. One case underwent risk-reductive salpingo-oophorectomy as a BRCA1 mutant carrier was retrospectively diagnosed as occult cancer. Common TP53 mutations were detected in cancer and fallopian tube epithelial cells in the case. Here, we integrate family cancer history and histology in ovarian cancer cases as well as TP53 status in a BRCA1 mutant case into a discussion regarding carcinogenesis in a Japanese population. The TP53 status for the BRCA1 mutant case examined here supports the recently proposed theory that ovarian cancer develops because of BRCA1 or BRCA2 inactivation and/or TP53 mutations.

  10. Analysis list: TP53 [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available TP53 Blood,Bone,Breast,Digestive tract,Epidermis,Others,Pluripotent stem cell + hg19 http:...//dbarchive.biosciencedbc.jp/kyushu-u/hg19/target/TP53.1.tsv http://dbarchive.biosciencedbc.jp/kyushu...-u/hg19/target/TP53.5.tsv http://dbarchive.biosciencedbc.jp/kyushu-u/hg19/target/TP53.10.tsv http://dbarchiv...e.biosciencedbc.jp/kyushu-u/hg19/colo/TP53.Blood.tsv,http://dbarchive.bioscienced...bc.jp/kyushu-u/hg19/colo/TP53.Bone.tsv,http://dbarchive.biosciencedbc.jp/kyushu-u/hg19/colo/TP53.Breast.tsv,http:

  11. TP53 gene status affects survival in advanced mycosis fungoides

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    Gitte Wooler

    2016-11-01

    Full Text Available TP53 is frequently mutated in different types of neoplasms including leukemia and lymphomas. Mutations of TP53 have also been reported in mycosis fungoides (MF, the most common type of cutaneous lymphoma. However, little is known about the frequency, spectrum of mutations and their prognostic significance in MF. In this study we have optimized the protocol for Sanger sequencing of TP53 using DNA extracted from archival paraffin-embedded biopsies. Of 19 samples from patients with stage IIB MF or higher, 31% harboured mutations in TP53. Overall survival of the patients with mutated TP53 was significantly shorter than median survival in the age- and stage-matched patients treated in our Institution. Distribution of mutations was heterogenous in TP53 exons, however C>T transitions were common suggesting the causal role of ultraviolet radiation. We propose that TP53 mutation status would be useful for risk stratification of patients with advanced MF.

  12. Creation and preliminary characterization of a Tp53 knockout rat

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    McCoy, Aaron; Besch-Williford, Cynthia L.; Franklin, Craig L.; Weinstein, Edward J.; Cui, Xiaoxia

    2013-01-01

    SUMMARY The tumor suppressor TP53 plays a crucial role in cancer biology, and the TP53 gene is the most mutated gene in human cancer. Trp53 knockout mouse models have been widely used in cancer etiology studies and in search for a cure of cancer with some limitations that other model organisms might help overcome. Via pronuclear microinjection of zinc finger nucleases (ZFNs), we created a Tp53 knockout rat that contains an 11-bp deletion in exon 3, resulting in a frameshift and premature terminations in the open reading frame. In cohorts of 25 homozygous (Tp53Δ11/Δ11), 37 heterozygous (Tp53Δ11/+) and 30 wild-type rats, the Tp53Δ11/Δ11 rats lived an average of 126 days before death or removal from study because of clinical signs of abnormality or formation of tumors. Half of Tp53Δ11/+ were removed from study by 1 year of age because of tumor formation. Both Tp53Δ11/+ and Tp53Δ11/Δ11 rats developed a wide spectrum of tumors, most commonly sarcomas. Interestingly, there was a strikingly high incidence of brain lesions, especially in Tp53Δ11/Δ11 animals. We believe that this mutant rat line will be useful in studying cancer types rarely observed in mice and in carcinogenicity assays for drug development. PMID:22917926

  13. Phylogenetic analysis of human Tp53 gene using computational ...

    African Journals Online (AJOL)

    format and was studied for its relationships and percent similarity within human and others species. Genetic variation among TP53 found in human beings and other organisms were studied in detail. Multiple sequence alignment and phylogenetic analysis of the human TP53, transcript variant-1 mRNA sequence through ...

  14. TP53 Mutation and Its Prognostic Significance in Waldenstrom's Macroglobulinemia.

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    Poulain, Stéphanie; Roumier, Christophe; Bertrand, Elisabeth; Renneville, Aline; Caillault-Venet, Aurélie; Doye, Emmanuelle; Geffroy, Sandrine; Sebda, Sheherazade; Nibourel, Olivier; Nudel, Morgane; Herbaux, Charles; Renaud, Loic; Tomowiak, Cécile; Guidez, Stéphanie; Tricot, Sabine; Roche-Lestienne, Catherine; Quesnel, Bruno; Preudhomme, Claude; Leleu, Xavier

    2017-10-15

    Purpose:TP53 is a tumor-suppressor gene that functions as a regulator influencing cellular responses to DNA damage, and TP53 alterations are associated with pejorative outcome in most B-lymphoid disorders. Little is known regarding TP53 alteration in Waldenstrom's macroglobulinemia (WM).Experimental Design: Here, we have explored the incidence of TP53 alteration using Sanger sequencing and ultradeep-targeted sequencing in 125 WM and 10 immunoglobulin M (IgM) monoclonal gammopathy of undetermined significance (MGUS), along with the clinical features and the associated genomic landscape using single-nucleotide polymorphism array and mutational landscape in an integrative study.Results: Overall, we have identified alteration of TP53 locus including mutation, deletion, and copy-neutral LOH in 11.2% of WM. TP53 mutation was acquired in 7.3% of patients with WM at diagnosis, being absent in IgM MGUS, and was highly correlated to deletion 17p. No correlation with CXCR4 mutations was observed. Patients with TP53 alteration had a greater number of genomic abnormalities. Importantly, WM with TP53 alteration had a significantly shorter overall survival, particularly in symptomatic WM, and independently of the international prognostic scoring system for Waldenstrom macroglobulinemia (IPSSWM) score. Specific treatment for WM with TP53 may have to be studied. Nutlin-3a-targeted p53 signaling induced cytotoxicity preclinically, along with new compounds such as ibrutinib, PrimaMet, or CP31398 that bypass p53 pathway in WM, paving the path for future treatment-tailored options.Conclusions: Our results highlight the clinical significance of detection of TP53 alteration in WM to determine the prognosis of WM and guide the treatment choice. Clin Cancer Res; 23(20); 6325-35. ©2017 AACR. ©2017 American Association for Cancer Research.

  15. TP53 mutations, tetraploidy and homologous recombination repair defects in early stage high-grade serous ovarian cancer

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    Chien, Jeremy; Sicotte, Hugues; Fan, Jian-Bing; Humphray, Sean; Cunningham, Julie M.; Kalli, Kimberly R.; Oberg, Ann L.; Hart, Steven N.; Li, Ying; Davila, Jaime I.; Baheti, Saurabh; Wang, Chen; Dietmann, Sabine; Atkinson, Elizabeth J.; Asmann, Yan W.; Bell, Debra A.; Ota, Takayo; Tarabishy, Yaman; Kuang, Rui; Bibikova, Marina; Cheetham, R. Keira; Grocock, Russell J.; Swisher, Elizabeth M.; Peden, John; Bentley, David; Kocher, Jean-Pierre A.; Kaufmann, Scott H.; Hartmann, Lynn C.; Shridhar, Viji; Goode, Ellen L.

    2015-01-01

    To determine early somatic changes in high-grade serous ovarian cancer (HGSOC), we performed whole genome sequencing on a rare collection of 16 low stage HGSOCs. The majority showed extensive structural alterations (one had an ultramutated profile), exhibited high levels of p53 immunoreactivity, and harboured a TP53 mutation, deletion or inactivation. BRCA1 and BRCA2 mutations were observed in two tumors, with nine showing evidence of a homologous recombination (HR) defect. Combined Analysis with The Cancer Genome Atlas (TCGA) indicated that low and late stage HGSOCs have similar mutation and copy number profiles. We also found evidence that deleterious TP53 mutations are the earliest events, followed by deletions or loss of heterozygosity (LOH) of chromosomes carrying TP53, BRCA1 or BRCA2. Inactivation of HR appears to be an early event, as 62.5% of tumours showed a LOH pattern suggestive of HR defects. Three tumours with the highest ploidy had little genome-wide LOH, yet one of these had a homozygous somatic frame-shift BRCA2 mutation, suggesting that some carcinomas begin as tetraploid then descend into diploidy accompanied by genome-wide LOH. Lastly, we found evidence that structural variants (SV) cluster in HGSOC, but are absent in one ultramutated tumor, providing insights into the pathogenesis of low stage HGSOC. PMID:25916844

  16. TP53 Mutations in Nonsmall Cell Lung Cancer

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    Akira Mogi

    2011-01-01

    Full Text Available The tumor suppressor gene TP53 is frequently mutated in human cancers. Abnormality of the TP53 gene is one of the most significant events in lung cancers and plays an important role in the tumorigenesis of lung epithelial cells. Human lung cancers are classified into two major types, small cell lung cancer (SCLC and nonsmall cell lung cancer (NSCLC. The latter accounts for approximately 80% of all primary lung cancers, and the incidence of NSCLC is increasing yearly. Most clinical studies suggest that NSCLC with TP53 alterations carries a worse prognosis and may be relatively more resistant to chemotherapy and radiation. A deep understanding of the role of TP53 in lung carcinogenesis may lead to a more reasonably targeted clinical approach, which should be exploited to enhance the survival rates of patients with lung cancer. This paper will focus on the role of TP53 in the molecular pathogenesis, epidemiology, and therapeutic strategies of TP53 mutation in NSCLC.

  17. TP53 and Beta-catenin mutations in liver tumours

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    Pierre Hainaut

    2007-02-01

    Full Text Available

    HBV and HCV play key roles in the etiopathogenesis of Hepatocellular carcinoma (HCC . Studies mostly based on cases from Western countries suggest distinct genetic pathways of carcinogenesis involving either TP53 or CTTNB1 mutations. Inappropriate reactivation of Wnt pathway due to mutations in CTNNB1 (Beta-Catenin gene itself is also frequently reported. Mutant Beta-catenin escapes to ubiquitination and down regulation by GSK3-B, it accumulates and trans-activates variety of oncogenes involved in neoplasmic transformation mimicking Wnt pathway activation. Taking into consideration viral infection, chromosome instability and TP53 /Beta-catenin alterations, Laurent-Puig et al. described two distinct HCC profiles in a serie of 137 HCC cases , the first one associates HBV infection with frequent chromosomal alteration and distributes with TP53 mutations, the second would be observed in HBV negative large sized tumors and distributes with Beta-catenin mutations. We have investigated the status of HBV and HCV infections and of genetic alterations in TP53 and CTTNB1 in 26 patients with HCC from Thailand. In tumours, HBV DNA was found in 19 cases (73% and HCV RNA in 4 cases (15.4% cases, 3 of whom were co-infected. Among the 19 HBV positive cases, sequencing of S gene showed genotype C in 82% and genotype B in 18%. Furthermore, 5/19 cases were negative for HBsAg and were categorized as occult HBV infections. TP53 mutations were detected in 9 cases (34,6% including 7 mutations at codon 249 (AGG to AGT, arginine to serine, considered as ";fingerprint"; of mutagenesis by aflatoxin metabolites. All cases with 249ser mutation had overt HBV infection.

    CTNNB1 mutations were found in 6/26 cases (23%, 4 of whom also had TP53 mutation. There was no significant association between CTTNB1

  18. Number of rare germline CNVs and TP53 mutation types.

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    Silva, Amanda G; Achatz, Isabel Maria W; Krepischi, Ana Cv; Pearson, Peter L; Rosenberg, Carla

    2012-12-21

    The Li-Fraumeni syndrome (LFS), an inherited rare cancer predisposition syndrome characterized by a variety of early-onset tumors, is caused by different highly penetrant germline mutations in the TP53 gene; each separate mutation has dissimilar functional and phenotypic effects, which partially clarifies the reported heterogeneity between LFS families. Increases in copy number variation (CNV) have been reported in TP53 mutated individuals, and are also postulated to contribute to LFS phenotypic variability. The Brazilian p.R337H TP53 mutation has particular functional and regulatory properties that differ from most other common LFS TP53 mutations, by conferring a strikingly milder phenotype. We compared the CNV profiles of controls, and LFS individuals carrying either p.R337H or DNA binding domain (DBD) TP53 mutations by high resolution array-CGH. Although we did not find any significant difference in the frequency of CNVs between LFS patients and controls, our data indicated an increased proportion of rare CNVs per genome in patients carrying DBD mutations compared to both controls (p=0.0002***) and p.R337H (0.0156*) mutants. The larger accumulation of rare CNVs in DBD mutants may contribute to the reported anticipation and severity of the syndrome; likewise the fact that p.R337H individuals do not present the same magnitude of rare CNV accumulation may also explain the maintenance of this mutation at relatively high frequency in some populations.

  19. Number of rare germline CNVs and TP53 mutation types

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    Silva Amanda G

    2012-12-01

    Full Text Available Abstract Background The Li-Fraumeni syndrome (LFS, an inherited rare cancer predisposition syndrome characterized by a variety of early-onset tumors, is caused by different highly penetrant germline mutations in the TP53 gene; each separate mutation has dissimilar functional and phenotypic effects, which partially clarifies the reported heterogeneity between LFS families. Increases in copy number variation (CNV have been reported in TP53 mutated individuals, and are also postulated to contribute to LFS phenotypic variability. The Brazilian p.R337H TP53 mutation has particular functional and regulatory properties that differ from most other common LFS TP53 mutations, by conferring a strikingly milder phenotype. Methods We compared the CNV profiles of controls, and LFS individuals carrying either p.R337H or DNA binding domain (DBD TP53 mutations by high resolution array-CGH. Results Although we did not find any significant difference in the frequency of CNVs between LFS patients and controls, our data indicated an increased proportion of rare CNVs per genome in patients carrying DBD mutations compared to both controls (p=0.0002*** and p.R337H (0.0156* mutants. Conclusions The larger accumulation of rare CNVs in DBD mutants may contribute to the reported anticipation and severity of the syndrome; likewise the fact that p.R337H individuals do not present the same magnitude of rare CNV accumulation may also explain the maintenance of this mutation at relatively high frequency in some populations.

  20. Profile of TP53 gene mutations in sinonasal cancer

    DEFF Research Database (Denmark)

    Holmila, Reetta; Bornholdt, Jette; Suitiala, Tuula

    2010-01-01

    Genetic alterations underlying the development of the cancer of the nose and paranasal sinuses (sinonasal cancer, SNC), a rare cancer that can be included in the group of head and neck cancers, are still largely unknown. We recently reported that TP53 mutations are a common feature of SNC, with a...

  1. TP53 codon 72 polymorphism in pigmentary phenotypes

    Indian Academy of Sciences (India)

    2012-01-20

    Jan 20, 2012 ... oedema and possibly pain and blistering (sunburn). Al- though associations between TP53 codon 72 polymorphism and various types of cancer, ..... Radiation-induced cutaneous carcinoma of the head and neck: is there an early role for p53 mutations? Clin. Exp. Dermatol. 31 793–798. Han J, Kraft P, Nan ...

  2. Germline mutations of TP53 gene in breast cancer.

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    Damineni, Surekha; Rao, Vadlamudi Raghavendra; Kumar, Satish; Ravuri, Rajasekar Reddy; Kagitha, Sailaja; Dunna, Nageswara Rao; Digumarthi, Raghunadharao; Satti, Vishnupriya

    2014-09-01

    Germline alterations of the TP53 gene encoding the p53 protein have been observed in the majority of families with the Li-Fraumeni syndrome, a rare dominantly inherited disorder with breast cancer. Genomic DNA samples of 182 breast cancer cases and 186 controls were sequenced for TP53 mutations in the exon 5-9 and intervening introns 5, 7-9. Direct sequencing was done using Applied Biosystem 3730 DNA analyzer. In the present study, we observed nine mutations in the sequenced region, of which five were novel. Hardy-Weinberg equilibrium (HWE) was done for all the mutations; C14181T, T14201G, and G13203A have shown deviation from HWE. High linkage disequilibrium (LD) was observed between C14181T (rs129547788) and T14201G (rs12951053) (r (2) = 0.98.3; D' = 1.00), whereas other observed mutations do not show strong LD with any of the other mutations. None of the intronic mutations has shown significant association with the breast cancer, two exonic mutations G13203A (rs28934578) and A14572G are significantly (P = 0.04, P = 0.007) associated with breast cancer. Germline mutations observed in DNA-binding domain of the gene showed significant association with breast cancer. This study reports five novel germline mutations in the TP53 gene out of which one mutation may confer significant risk to the breast cancer. Mutations in DNA-binding domain of TP53 gene may play role in the early onset and prognosis of breast cancer. The population-based studies of germline mutations in DNA-binding domain of TP53 gene helps in identification of individuals and families who are at risk of developing cancers.

  3. Genomic analysis of inherited breast cancer among Palestinian women: Genetic heterogeneity and a founder mutation in TP53.

    Science.gov (United States)

    Lolas Hamameh, Suhair; Renbaum, Paul; Kamal, Lara; Dweik, Dima; Salahat, Mohammad; Jaraysa, Tamara; Abu Rayyan, Amal; Casadei, Silvia; Mandell, Jessica B; Gulsuner, Suleyman; Lee, Ming K; Walsh, Tom; King, Mary-Claire; Levy-Lahad, Ephrat; Kanaan, Moein

    2017-08-15

    Breast cancer among Palestinian women has lower incidence than in Europe or North America, yet is very frequently familial. We studied genetic causes of this familial clustering in a consecutive hospital-based series of 875 Palestinian patients with invasive breast cancer, including 453 women with diagnosis by age 40, or with breast or ovarian cancer in a mother, sister, grandmother or aunt ("discovery series"); and 422 women diagnosed after age 40 and with negative family history ("older-onset sporadic patient series"). Genomic DNA from women in the discovery series was sequenced for all known breast cancer genes, revealing a pathogenic mutation in 13% (61/453) of patients. These mutations were screened in all patients and in 300 Palestinian female controls, revealing 1.0% (4/422) carriers among older, nonfamilial patients and two carriers among controls. The mutational spectrum was highly heterogeneous, including pathogenic mutations in 11 different genes: BRCA1, BRCA2, TP53, ATM, CHEK2, BARD1, BRIP1, PALB2, MRE11A, PTEN and XRCC2. BRCA1 carriers were significantly more likely than other patients to have triple negative tumors (p = 0.03). The single most frequent mutation was TP53 p.R181C, which was significantly enriched in the discovery series compared to controls (p = 0.01) and was responsible for 15% of breast cancers among young onset or familial patients. TP53 p.R181C predisposed specifically to breast cancer with incomplete penetrance, and not to other Li-Fraumeni cancers. Palestinian women with young onset or familial breast cancer and their families would benefit from genetic analysis and counseling. © 2017 UICC.

  4. The IARC TP53 mutation database: a resource for studying the significance of TP53 mutations in human cancers

    Directory of Open Access Journals (Sweden)

    Magali Olivier

    2007-02-01

    Full Text Available

    The tumor suppressor gene TP53 is frequently inactivated by gene mutations in many types of human sporadic cancers, and inherited TP53 mutations predispose to a wide spectrum of early-onset tumors (Li-Fraumeni et Li-Fraumenilike Syndromes. All TP53 gene variations (somatic and germline mutations, as well as polymorphisms that are reported in the scientific literature or in SNP databases are compiled in the IARC TP53 Database. This database provides structured data and analysis tools to study mutation patterns in human cancers and cell-lines and to investigate the clinical impact of mutations. It contains annotations related to the clinical and pathological characteristics of tumors, as well as the demographics and carcinogen exposure of patients. The IARC TP53 web site (http://www-p53.iarc.fr/ provides a search interface for the core database and includes a comprehensive user guide, a slideshow on TP53 mutations in human cancer, protocols and references for sequencing TP53 gene, and links to relevant publications and bioinformatics databases. The database interface allows download of entire data sets and propose various tools for the selection, analysis and downloads of specific sets of data according to user's query.

    Recently, new annotations on the functional properties of mutant p53 proteins have been integrated in this database. Indeed, the most frequent TP53 alterations observed in cancers (75% are missense mutations that result in the production of a mutant protein that differ from the wildtype by one single amino-acid. The characterization of the biological activities of these mutant proteins is thus very important. Over the last ten years, a great amount of systematic data has been generated from experimental assays performed in

  5. TP53 Gene Status Affects Survival in Advanced Mycosis Fungoides

    DEFF Research Database (Denmark)

    Wooler, Gitte; Melchior, Linea; Ralfkiaer, Elisabeth

    2016-01-01

    significance in MF. In this study, we have optimized the protocol for Sanger sequencing of TP53 using DNA extracted from archival paraffin-embedded biopsies. Of 19 samples from patients with stage IIB MF or higher, 31% harbored mutations in TP53. Overall survival of the patients with mutated TP53...

  6. LOS GENES BRCA1 y BRCA2. ESTUDIO MOLECULAR

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    N. Alonso

    2006-11-01

    Full Text Available RESUMENEn los últimos años, se realizaron numerosos estudios para establecer la predisposición hereditaria al cáncer y las alteraciones mutacionales a nivel de genes susceptibles de originar cáncer de mama y ovario. En 1994 se identificaron los genes BRCA1 (Breast Cancer Gene 1 y BRCA2 (Breast Cancer Gene 2 como susceptibles de cáncer de mama y ovario. En la actualidad se sabe que las mutaciones en BRCA1 y BRCA2 están lejos de explicar la totalidad de los casos de cáncer de mama y/o ovario, y a pesar de que se postulan alteraciones mutacionales en otros genes como CHEK2, TP53 y PTEN, el BRCA1 y BRCA2, siguen teniendo su importancia y utilidad en la valoración del riesgo de predisposición hereditaria. Aunque las cifras son variables según los distintos estudios y autores, se trata en cualquier caso de porcentajes importantes. Entre el 15 y el 85% de las mujeres portadoras de mutación BRCA 1 o BRCA 2 tienen riesgo de desarrollar un cáncer de mama y entre un 10 y 60% de desarrollar un cáncer de ovario. ABSTRACT:In the last years, numerous studies were made to establish the hereditary predisposition to the cancer and the mutationals alterations at level of genes susceptible to originate breast and ovarian cancers. In 1994 genes BRCA1 (Breast Cancer Gene 1 and BRCA2 were identified (Breast Cancer Gene 2 as susceptible of both of breast and ovarian cancers. At the present time, it is knows that the mutations in BRCA 1 and BRCA 2 are far from explaining the totality of the cases of breast cancer and/or ovary, and although mutationals alterations in other genes like CHEK2, TP53 and PTEN, the BRCA1 and BRCA2 are postulated, they continue having his importance and utility in the valuation of the risk of hereditary predisposition. Correlations between both BRCA1 and BRCA2 levels with tumour grade metastasis and prognostic accuracy. Between 15 and 85% of the carrying women of mutation BRCA 1 or BRCA 2 have risk of developing a cancer of breast

  7. HPV-negative penile squamous cell carcinoma: disruptive mutations in the TP53 gene are common.

    Science.gov (United States)

    Kashofer, Karl; Winter, Elke; Halbwedl, Iris; Thueringer, Andrea; Kreiner, Marisa; Sauer, Stefan; Regauer, Sigrid

    2017-07-01

    The majority of penile squamous cell carcinomas is caused by transforming human papilloma virus (HPV) infection. The etiology of HPV-negative cancers is unclear, but TP53 mutations have been implicated. Archival tissues of 108 invasive squamous cell carcinoma from a single pathology institution in a low-incidence area were analyzed for HPV-DNA and p16ink4a overexpression and for TP53 mutations by ion torrent next-generation sequencing. Library preparation failed in 32/108 squamous cell carcinomas. Institutional review board approval was obtained. Thirty of 76 squamous cell carcinomas (43%; average 63 years) were HPV-negative with 8/33 squamous cell carcinomas being TP53 wild-type (24%; average 63 years). Twenty-five of 33 squamous cell carcinomas (76%; average 65 years) showed 32 different somatic TP53 mutations (23 missense mutations in exons 5-8, 6 nonsense, 1 frameshift and 2 splice-site mutations). Several hotspot mutations were detected multiple times (R175H, R248, R282, and R273). Eighteen of 19 squamous cell carcinomas with TP53 expression in immunohistochemistry had TP53 mutations. Fifty percent of TP53-negative squamous cell carcinomas showed mostly truncating loss-of-function TP53 mutations. Patients without mutations had longer survival (5 years: 86% vs 61%; 10 years: 60% vs 22%), but valid clinically relevant conclusions cannot be drawn due to different tumor stages and heterogeneous treatment of the cases presented in this study. Somatic TP53 mutations are a common feature in HPV-negative penile squamous cell carcinomas and offer an explanation for HPV-independent penile carcinogenesis. About half of HPV-negative penile cancers are driven by oncogenic activation of TP53, while a quarter is induced by loss of TP53 tumor suppressor function. Detection of TP53 mutations should be carried out by sequencing, as immunohistochemical TP53 staining could not identify all squamous cell carcinomas with TP53 mutations.

  8. TP53 mutations in advanced colorectal cancer: the dark side of the moon.

    Science.gov (United States)

    Pietrantonio, Filippo; Biondani, Pamela; Perrone, Federica; Di Bartolomeo, Maria; Pacifici, Monica; Milione, Massimo; Melotti, Flavia; Maggi, Claudia; Montemurro, Gabriella; Bossi, Ilaria; Mariani, Luigi; de Braud, Filippo

    2014-01-01

    Evidence for TP53 mutations as biomarker in colorectal cancer (CRC) is conflicting. We assessed TP53 mutations in 51 patients with advanced CRC enrolled into a phase II, randomised trial of first-line tegafur-uracil (UFT)/leucovorin (LV) plus irinotecan (n = 23) versus UFT/LV plus oxaliplatin (n = 28). Non-functional TP53 mutations were found in 35% of patients. The response rate was not significantly different according to TP53 status. Progression-free and overall survival were longer in patients with TP53 mutations compared to those with wild-type TP53 (9 vs. 6.5 months, p = 0.0504, and 39.2 vs. 19.6 months, p = 0.0055, respectively). On multivariable analysis, TP53 mutation was independently associated with a decreased risk of death (hazard ratio 0.329, 95% CI 0.159-0.679; p = 0.0026). Treatment arm did not interact with TP53 in influencing outcomes. TP53 was not predictive of benefit from first-line irinotecan- or oxaliplatin-based chemotherapy. TP53 mutations may possibly be associated with a more indolent course of CRC after the diagnosis of metastatic disease. © 2014 S. Karger AG, Basel.

  9. Identification of a core TP53 transcriptional program with highly distributed tumor suppressive activity.

    Science.gov (United States)

    Andrysik, Zdenek; Galbraith, Matthew D; Guarnieri, Anna L; Zaccara, Sara; Sullivan, Kelly D; Pandey, Ahwan; MacBeth, Morgan; Inga, Alberto; Espinosa, Joaquín M

    2017-10-01

    The tumor suppressor TP53 is the most frequently mutated gene product in human cancer. Close to half of all solid tumors carry inactivating mutations in the TP53 gene, while in the remaining cases, TP53 activity is abrogated by other oncogenic events, such as hyperactivation of its endogenous repressors MDM2 or MDM4. Despite identification of hundreds of genes regulated by this transcription factor, it remains unclear which direct target genes and downstream pathways are essential for the tumor suppressive function of TP53. We set out to address this problem by generating multiple genomic data sets for three different cancer cell lines, allowing the identification of distinct sets of TP53-regulated genes, from early transcriptional targets through to late targets controlled at the translational level. We found that although TP53 elicits vastly divergent signaling cascades across cell lines, it directly activates a core transcriptional program of ∼100 genes with diverse biological functions, regardless of cell type or cellular response to TP53 activation. This core program is associated with high-occupancy TP53 enhancers, high levels of paused RNA polymerases, and accessible chromatin. Interestingly, two different shRNA screens failed to identify a single TP53 target gene required for the anti-proliferative effects of TP53 during pharmacological activation in vitro. Furthermore, bioinformatics analysis of thousands of cancer genomes revealed that none of these core target genes are frequently inactivated in tumors expressing wild-type TP53. These results support the hypothesis that TP53 activates a genetically robust transcriptional program with highly distributed tumor suppressive functions acting in diverse cellular contexts. © 2017 Andrysik et al.; Published by Cold Spring Harbor Laboratory Press.

  10. Are There Low-Penetrance TP53 Alleles? Evidence from Childhood Adrenocortical Tumors

    OpenAIRE

    Varley, Jennifer M.; McGown, Gail; Thorncroft, Mary; James, Louise A.; Margison, Geoffrey P.; Forster, Gill; Evans, D. Gareth R.; Harris, Martin; Kelsey, Anna M.; Birch, Jillian M.

    1999-01-01

    We have analyzed a panel of 14 cases of childhood adrenocortical tumors unselected for family history and have identified germline TP53 mutations in >80%, making this the highest known incidence of a germline mutation in a tumor-suppressor gene in any cancer. The spectrum of germline TP53 mutations detected is remarkably limited. Analysis of tumor tissue for loss of constitutional heterozygosity, with respect to the germline mutant allele and the occurrence of other somatic TP53 mutations, in...

  11. TP53 Mutations and Survival in Osteosarcoma Patients: A Meta-Analysis of Published Data

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    Zhe Chen

    2016-01-01

    Full Text Available Several research groups have examined the association between TP53 mutations and prognosis in human osteosarcoma. However, the results were controversial. The purpose of this study was to evaluate the prognostic value of TP53 mutations in osteosarcoma patients. A meta-analysis was conducted with all eligible studies which quantitatively evaluated the relationship between TP53 mutations and clinical outcome of osteosarcoma patients. Eight studies with a total of 210 patients with osteosarcoma were included in this meta-analysis. The risk ratio (RR with a 95% confidence interval (95% CI was calculated to assess the effect of TP53 mutations on 2-year overall survival. The quantitative synthesis of 8 published studies showed that TP53 mutations were associated with 2-year overall survival in osteosarcoma patients. These data suggested that TP53 mutations had an unfavorable impact on 2-year overall survival when compared to the counterparts with wild type (WT TP53 (RR: 1.79; 95% CI: 1.12 to 2.84; P=0.01; I2=0%. There was no between-study heterogeneity. TP53 mutations are an effective prognostic marker for survival of patients with osteosarcoma. However, further large-scale prospective trials should be performed to clarify the prognostic value of TP53 mutations on 3- or 5-year survival in osteosarcoma patients.

  12. Low Prevalence of TP53 Mutations and MDM2 Amplifications in Pediatric Rhabdomyosarcoma

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    Simona Ognjanovic

    2012-01-01

    Full Text Available The tumor suppressor gene TP53 is the most commonly mutated gene in human cancer. The reported prevalence of mutations in rhabdomyosarcoma (RMS varies widely, with recent larger studies suggesting that TP53 mutations in pediatric RMS may be extremely rare. Overexpression of MDM2 also attenuates p53 function. We have performed TP53 mutation/MDM2 amplification analyses in the largest series analyzed thus far, including DNA isolated from 37 alveolar and 38 embryonal RMS tumor samples obtained from the Cooperative Human Tissue Network (CHTN. Available samples were frozen tumor tissues (N=48 and histopathology slides. TP53 mutations in exons 4–9 were analyzed by direct sequencing in all samples, and MDM2 amplification analysis was performed by differential PCR on a subset of 22 samples. We found only one sample (1/75, 1.3% carrying a TP53 mutation at codon 259 (p.D259Y and no MDM2 amplification. Two SNPs in the TP53 pathway, associated with accelerated tumor onset in germline TP53 mutation carriers, (TP53 SNP72 (rs no. 1042522 and MDM2 SNP309 (rs no. 2279744, were not found to confer earlier tumor onset. In conclusion, we confirm the extremely low prevalence of TP53 mutations/MDM2 amplifications in pediatric RMS (1.33% and 0%, respectively. The possible inactivation of p53 function by other mechanisms thus remains to be elucidated.

  13. TP53 mutation spectrum in smokers and never smoking lung cancer patients

    Directory of Open Access Journals (Sweden)

    Ann Rita Halvorsen

    2016-05-01

    Full Text Available AbstractBackground: TP53 mutations are among the most common mutations found in lung cancers, identified as an independent prognostic factor in many types of cancers. The purpose of this study was to investigate the frequency and prognostic impact of TP53 mutations in never-smokers and in different histological subtypes of lung cancer.Methods: We analysed tumour tissue from 394 non-small cell carcinomas including adenocarcinomas (n=229, squamous cell carcinomas (n=112, large cell carcinomas (n=30 and others (n=23 for mutations in TP53 by the use of Sanger sequencing (n=394 and next generation sequencing (n=100. Results: TP53 mutations were identified in 47.2% of the samples, with the highest frequency (65% of mutations among squamous cell carcinomas. Among never-smokers, 36% carried a TP53 mutation, identified as a significant independent negative prognostic factor in this subgroup. For large cell carcinomas, a significantly prolonged progression free survival was found for those carrying a TP53 mutation. In addition, the frequency of frameshift mutations was doubled in squamous cell carcinomas (20.3% compared to adenocarcinomas (9.1%.Conclusion: TP53 mutation patterns differ between the histological subgroups of lung cancers, as also influenced by smoking history. This indicates that the histological subtypes in lung cancer are genetically different, and that smoking-induced TP53 mutations may have a different biological impact than TP53 mutations occurring in never-smokers.

  14. Prevalence of germline TP53 mutations in HER2+ breast cancer patients.

    Science.gov (United States)

    Rath, Michelle G; Masciari, Serena; Gelman, Rebecca; Miron, Alexander; Miron, Penelope; Foley, Kathleen; Richardson, Andrea L; Krop, Ian E; Verselis, Sigitas J; Dillon, Deborah A; Garber, Judy E

    2013-05-01

    Breast cancer is the most frequent tumor in Li-Fraumeni syndrome (LFS), a rare inherited cancer syndrome associated with germline mutations in the TP53 gene. Recent data show that breast cancer in germline TP53 mutation carriers is commonly HER2+ (63-83 %). We assessed the prevalence of germline TP53 mutations in a cohort of women with HER2+ breast cancer diagnosed age ≤50 years. We identified blood specimens from 213 women with primary invasive HER2+ breast cancer age ≤50 years from a single center. Exon grouping analysis sequencing and multiplex ligation-dependent probe amplification techniques were used to screen for germline TP53 mutations. Among 213 women with HER2+ breast cancer age ≤50 years, 3 (ages at diagnosis 23, 32, 44 years) were found to carry a TP53 mutation (1.4 %, 95 % CI 0.3-4.1 %). ER/PR status was not uniform. Two TP53 carriers met Chompret criteria for LFS; none met classic LFS criteria. Although two-thirds of breast cancers in women with TP53 mutations are HER2+, we observed a low prevalence of germline TP53 mutations among unselected young women with HER2+ breast cancer. Given the potential clinical impact, consideration of germline TP53 testing should be given to young women with HER2+ breast cancer, especially if family cancer history is notable.

  15. Prevalence of germline TP53 mutations in HER2-positive Breast Cancer Patients

    Science.gov (United States)

    Rath, Michelle G.; Masciari, Serena; Gelman, Rebecca; Miron, Alexander; Miron, Penelope; Foley, Kathleen; Richardson, Andrea L.; Krop, Ian E.; Verselis, Sigitas J.; Dillon, Deborah A.; Garber, Judy E.

    2014-01-01

    Background Breast cancer is the most frequent tumor in Li-Fraumeni syndrome (LFS), a rare inherited cancer syndrome associated with germline mutations in the TP53 gene. Recent data show that breast cancer in germline TP53 mutation carriers is commonly HER2-positive (63–83%). We assessed the prevalence of germline TP53 mutations in a cohort of women with HER2+ breast cancer diagnosed age ≤ 50 years. Material & Methods We identified blood specimens from 213 women with primary invasive HER2+ breast cancer age ≤ 50 years from a single center. EGAN sequencing and MLPA techniques were used to screen for germline TP53 mutations. Results Among 213 women with HER2+ breast cancer age ≤ 50 years, 3 (ages at diagnosis 23, 32, 44 years) were found to carry a TP53 mutation (1.4%, 95%CI 0.3%–4.1%). ER/PR status was not uniform. Two TP53-carriers met Chompret criteria for LFS; none met classic LFS criteria. Conclusion Although two-thirds of breast cancers in women with TP53 mutations are HER2+, we observed a low prevalence of germline TP53 mutations among unselected young women with HER2+ breast cancer. Given the potential clinical impact, consideration of germline TP53 testing should be given to young women with HER2+ breast cancer, especially if family cancer history is notable. PMID:23580068

  16. TP53inp1 Gene Is Implicated in Early Radiation Response in Human Fibroblast Cells

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    Nikolett Sándor

    2015-10-01

    Full Text Available Tumor protein 53-induced nuclear protein-1 (TP53inp1 is expressed by activation via p53 and p73. The purpose of our study was to investigate the role of TP53inp1 in response of fibroblasts to ionizing radiation. γ-Ray radiation dose-dependently induces the expression of TP53inp1 in human immortalized fibroblast (F11hT cells. Stable silencing of TP53inp1 was done via lentiviral transfection of shRNA in F11hT cells. After irradiation the clonogenic survival of TP53inp1 knockdown (F11hT-shTP cells was compared to cells transfected with non-targeting (NT shRNA. Radiation-induced senescence was measured by SA-β-Gal staining and autophagy was detected by Acridine Orange dye and microtubule-associated protein-1 light chain 3 (LC3B immunostaining. The expression of TP53inp1, GDF-15, and CDKN1A and alterations in radiation induced mitochondrial DNA deletions were evaluated by qPCR. TP53inp1 was required for radiation (IR induced maximal elevation of CDKN1A and GDF-15 expressions. Mitochondrial DNA deletions were increased and autophagy was deregulated following irradiation in the absence of TP53inp1. Finally, we showed that silencing of TP53inp1 enhances the radiation sensitivity of fibroblast cells. These data suggest functional roles for TP53inp1 in radiation-induced autophagy and survival. Taken together, we suppose that silencing of TP53inp1 leads radiation induced autophagy impairment and induces accumulation of damaged mitochondria in primary human fibroblasts.

  17. FGFR3 and TP53 mutations in a prospective cohort of Belarusian bladder cancer patients.

    Science.gov (United States)

    Smal, M P; Rolevich, A I; Polyakov, S L; Krasny, S A; Goncharova, R I

    2014-12-01

    The aim of this study was to determine the frequencies of FGFR3 and TP53 mutations in a prospective cohort of 150 bladder cancer patients and to assess the relationship between their mutational status and clinicopathological variables. The FGFR3 and TP53 mutations were detected by the SNaPshot method and PCR-single-strand conformational polymorphism analysis followed by DNA sequencing. The activating FGFR3 mutations were found in 71 (47.3%) whereas TP53 mutations were observed in 31 (20.7%) urothelial carcinomas. FGFR3-mutant tumors significantly correlated with lower tumor stage and grade, papillary form of bladder cancer and the absence of metastases while TP53-mutant tumors were strongly associated with higher tumor stage and grade as well as the presence of metastasis. We also found significant inverse correlation between FGFR3 mutations and TP53 alterations in urothelial carcinomas (p=0.03). Four possible genotypes were observed in the whole studied cohort, namely FGFR3mut/TP53wt (41.3%), FGFR3wt/TP53wt (38%), FGFR3wt/TP53mut (14.7%), and FGFR3mut/TP53mut (6%). Tumors with FGFR3wt/TP53wt genotype comprised the subgroup, in which all stages and grades were equally distributed. Our findings confirm the alternative role of FGFR3 and TP53 mutations in the development of bladder cancer. Together these two genetic markers are attributed to 62% of the tumors studied. Tumors with both wild type genes included urothelial carcinomas of all stages and grades and may develop through another genetic pathway. To elucidate complete molecular profile of bladder tumors further additional studies are needed.

  18. Bioinformatic dissecting of TP53 regulation pathway underlying butyrate-induced histone modification in epigenetic regulation

    Science.gov (United States)

    Butyrate affects cell proliferation, differentiation and motility. Butyrate inhibits histone deacetylase (HDAC) activities and induces cell cycle arrest and apoptosis. TP53 is one of the most active upstream regulators discovered by IPA in our RNA sequencing data set. The TP53 signaling pathway pl...

  19. Functional categories of TP53 mutation in colorectal cancer: results of an International Collaborative Study.

    NARCIS (Netherlands)

    Iacopetta, B.; Russo, A.; Bazan, V.; Dardanoni, G.; Gebbia, N.; Soussi, T.; Kerr, D.J.; Elsaleh, H.; Soong, R.; Kandioler, D.; Janschek, E.; Kappel, S.; Lung, M.; Leung, C.S.; Ko, J.M.; Yuen, S.; Ho, J.; Leung, S.Y.; Crapez, E.; Duffour, J.; Ychou, M.; Leahy, D.T.; O'Donoghue, D.P.; Agnese, V.; Cascio, S.; Fede, G. Di; Chieco-Bianchi, L.; Bertorelle, R.; Belluco, C.; Giaretti, W.; Castagnola, P.; Ricevuto, E.; Ficorella, C.; Bosari, S.; Arizzi, C.D.; Miyaki, M.; Onda, M.; Kampman, E.; Diergaarde, B.; Royds, J.; Lothe, R.A.; Diep, C.B.; Meling, G.I.; Ostrowski, J.; Trzeciak, L.; Guzinska-Ustymowicz, K.; Zalewski, B.; Capella, G.M.; Moreno, V.; Peinado, M.A.; Lonnroth, C.; Lundholm, K.; Sun, X.F.; Jansson, A.; Bouzourene, H.; Hsieh, L.L.; Tang, R.; Smith, D.R.; Allen-Mersh, T.G.; Khan, Z.A.; Shorthouse, A.J.; Silverman, M.L.; Kato, S.; Ishioka, C.

    2006-01-01

    BACKGROUND: Loss of TP53 function through gene mutation is a critical event in the development and progression of many tumour types including colorectal cancer (CRC). In vitro studies have found considerable heterogeneity amongst different TP53 mutants in terms of their transactivating abilities.

  20. Neurofibromin 1 (NF1 Defects Are Common in Human Ovarian Serous Carcinomas and Co-occur with TP53 Mutations

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    Navneet Sangha

    2008-12-01

    Full Text Available Ovarian serous carcinoma (OSC is the most common and lethal histologic type of ovarian epithelial malignancy. Mutations of TP53 and dysfunction of the Brca1 and/or Brca2 tumor-suppressor proteins have been implicated in the molecular pathogenesis of a large fraction of OSCs, but frequent somatic mutations in other well-established tumor-suppressor genes have not been identified. Using a genome-wide screen of DNA copy number alterations in 36 primary OSCs, we identified two tumors with apparent homozygous deletions of the NF1 gene. Subsequently, 18 ovarian carcinoma-derived cell lines and 41 primary OSCs were evaluated for NF1 alterations. Markedly reduced or absent expression of Nf1 protein was observed in 6 of the 18 cell lines, and using the protein truncation test and sequencing of cDNA and genomic DNA, NF1 mutations resulting in deletion of exons and/or aberrant splicing of NF1 transcripts were detected in 5 of the 6 cell lines with loss of NF1 expression. Similarly, NF1 alterations including homozygous deletions and splicing mutations were identified in 9 (22% of 41 primary OSCs. As expected, tumors and cell lines with NF1 defects lacked mutations in KRAS or BRAF but showed Ras pathway activation based on immunohistochemical detection of phosphorylated MAPK (primary tumors or increased levels of GTP-bound Ras (cell lines. The TP53 tumor-suppressor gene was mutated in all OSCs with documented NF1 mutation, suggesting that the pathways regulated by these two tumor-suppressor proteins often cooperate in the development of ovarian carcinomas with serous differentiation.

  1. Functional TP53 mutations have no impact on response to cytotoxic agents in metastatic colon cancer.

    Science.gov (United States)

    Netter, Jeanne; Lehmann-Che, Jacqueline; Lambert, Jerome; Tallet, Anne; Lourenco, Nelson; Soliman, Hany; Bertheau, Philippe; Pariente, Benjamin; Chirica, Mircea; Pocard, Marc; Allez, Matthieu; De The, Hugues; Gornet, Jean-Marc

    2015-02-01

    Survival of metastatic colon cancer (mCC) patients has considerably improved with optimization of new drugs regimen. Inactivation of TP53 pathway by TP53 mutations is observed in nearly half of colorectal tumors. The impact of such mutations has been poorly studied in the metastatic setting. The files of 254 mCC treated in a single institution at Saint-Louis hospital between January 1999 and April 2011 were retrospectively reviewed. Tissue samples for analysis of TP53 mutations were available for 68 patients, performed using FASAY. The prognostic value of TP53 status was evaluated by comparing progression free survival (PFS) and overall survival (OS) in the group of TP53-mutated and wild type patients. PFS was 6.9 months and OS 21.7 months in the whole population. There was no statistical difference in TP53-mutated and wild type groups in term of PFS (HR=1.04; IC 95%=0.6-1.79) and OS (HR=0.99; IC 95%=0.53-1.55) whatever the chemotherapy regimen (oxaliplatin- or irinotecan-based). Only BRAF V600 mutation was demonstrated to be a poor prognostic factor for PFS and OS, and CEA level for OS. Routine determination of TP53 mutations, even with a highly sensitive method, cannot be recommended to predict chemotherapy response in mCC. Copyright © 2015 Société Française du Cancer. Published by Elsevier Masson SAS. All rights reserved.

  2. TP53 mutants in the tower of babel of cancer progression.

    Science.gov (United States)

    Bisio, Alessandra; Ciribilli, Yari; Fronza, Gilberto; Inga, Alberto; Monti, Paola

    2014-06-01

    Loss-of-function, partial-function, altered-function, dominant-negative, temperature sensitive, interfering, contact, structural, unfolded, misfolded, dimeric, monomeric, non-cooperative, unstable, supertrans, superstable, intragenic suppressor. TP53 mutants are many, more than 2,000 in fact, and they can be very diverse. Sporadic; germline; gain-of-function (GoF); oncogenic; rebel-angel; yin and yang; prion-like; metastasis-inducer; mediator of chemo-resistance; modifier of stemness. TP53 mutants can impact important cancer clinical variables, in multiple, often subtle ways, as revealed by cell-based assays as well as animal models. Here, we review studies investigating TP53 mutants for their effect on sequence-specific transactivation function, and especially recent findings on how TP53 mutants can exhibit GoF properties. We also review reports on TP53 mutants' impact on cancer cell transcriptomes and studies with Li-Fraumeni patients trying to classify and predict phenotypes in relation to experimentally determined transcription fingerprints. Finally, we provide an example of the complexity of correlating TP53 mutant functionality to clinical variables in sporadic cancer patients. Conflicting results and limitations of experimental approaches notwithstanding, the study of TP53 mutants has provided a rich body of knowledge, mostly available in the public domain and accessible through databases, which is beginning to impact cancer intervention strategies. © 2014 WILEY PERIODICALS, INC.

  3. Differential angiogenic gene expression in TP53 wild-type and mutant ovarian cancer cell lines

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    Brittany Anne Davidson

    2014-06-01

    Full Text Available Objectives: Underlying mechanisms regulating angiogenesis in ovarian cancer have not been completely elucidated. Evidence suggests that the TP53 tumor suppressor pathway and tumor microenvironment play integral roles. We utilized microarray technology to study the interaction between TP53 mutational status & hypoxia on angiogenic gene expression.Methods: Affymetrix U133A arrays were analyzed for angiogenic gene expression in 19 ovarian cancer cell lines stratified both by TP53 mutation status and A2780 wild-type (wt TP53 vs. mutated (m TP53 cell lines after treatment under hypoxic conditions or with ionizing radiation. Results: Twenty-eight differentially expressed angiogenic genes were identified in the mTP53 cell lines compared to wtTP53 lines. Five genes were upregulated in mTP53 cells: 40% involved in extracellular matrix (ECM degradation (MMP10/15 and 60% in angiogenesis (FGFR3/VEGFA/EPHB4. Twenty-three genes were upregulated in wtTP53: nearly 22% were ECM constituents or involved in ECM degradation; over 40% were growth factors or mediators of angiogenesis. Five genes were upregulated in the A2780mTP53 cells: 40% involved in ECM remodeling (MMP10, ADAMTS1, 40% with pro-angiogenic activity (EFNB2, F2R, and 20% with anti-angiogenic properties (ADAMTS1. Three genes were upregulated in hypoxia treated cells compared to controls: 1 with anti-angiogenic activity (ANGPTL4 and 2 with pro-angiogenic activity (VEGFA, EFNA3. No significant gene fold changes were noted after exposure to radiation.Four genes continued to demonstrate significant differential expression (p≤0.05 after adjusting for multiple comparisons. These genes included ENG upregulation in wild-type lines and upregulation of FGF-20, ADAMTS1 & MMP10 in mTP53 lines.Conclusions: Our exploratory findings indicate that non-overlapping angiogenic pathways may be altered by TP53 mutations and hypoxic conditions in ththe tumor microenvironment. Further evaluation is needed for confirmation.

  4. BRCA1 and Oxidative Stress

    Directory of Open Access Journals (Sweden)

    Yong Weon Yi

    2014-04-01

    Full Text Available The breast cancer susceptibility gene 1 (BRCA1 has been well established as a tumor suppressor and functions primarily by maintaining genome integrity. Genome stability is compromised when cells are exposed to oxidative stress. Increasing evidence suggests that BRCA1 regulates oxidative stress and this may be another mechanism in preventing carcinogenesis in normal cells. Oxidative stress caused by reactive oxygen species (ROS is implicated in carcinogenesis and is used strategically to treat human cancer. Thus, it is essential to understand the function of BRCA1 in oxidative stress regulation. In this review, we briefly summarize BRCA1’s many binding partners and mechanisms, and discuss data supporting the function of BRCA1 in oxidative stress regulation. Finally, we consider its significance in prevention and/or treatment of BRCA1-related cancers.

  5. New recurrent deletions in the PPARgamma and TP53 genes are associated with childhood myelodysplastic syndrome

    DEFF Research Database (Denmark)

    Silveira, Cássia G T; Oliveira, Fábio M; Valera, Elvis T

    2009-01-01

    observed in 17 and 18 cases, respectively. Using quantitative RT-PCR, it was detected PPARgamma transcript downexpression in a subset of these cases. G-banding analysis revealed 17p deletions in a small number of these cases. One MDS therapy-related patient had neither a loss of PPARgamma nor TP53......Myelodysplastic syndrome (MDS) is a rare hematological malignancy in children. It was performed FISH analysis in 19 pediatric MDS patients to investigate deletions involving the PPARgamma and TP53 genes. Significant losses in the PPARgamma gene and deletions in the tumor suppressor gene TP53 were....... These data suggest that the PPARgamma and TP53 genes may be candidates for molecular markers in pediatric MDS, and that these potentially recurrent deletions could contribute to the identification of therapeutic approaches in primary pediatric MDS....

  6. Somatic and GermlineTP53Alterations in Second Malignant Neoplasms from Pediatric Cancer Survivors.

    Science.gov (United States)

    Sherborne, Amy L; Lavergne, Vincent; Yu, Katharine; Lee, Leah; Davidson, Philip R; Mazor, Tali; Smirnoff, Ivan V; Horvai, Andrew E; Loh, Mignon; DuBois, Steven G; Goldsby, Robert E; Neglia, Joseph P; Hammond, Sue; Robison, Leslie L; Wustrack, Rosanna; Costello, Joseph F; Nakamura, Alice O; Shannon, Kevin M; Bhatia, Smita; Nakamura, Jean L

    2017-04-01

    Purpose: Second malignant neoplasms (SMNs) are severe late complications that occur in pediatric cancer survivors exposed to radiotherapy and other genotoxic treatments. To characterize the mutational landscape of treatment-induced sarcomas and to identify candidate SMN-predisposing variants, we analyzed germline and SMN samples from pediatric cancer survivors. Experimental Design: We performed whole-exome sequencing (WES) and RNA sequencing on radiation-induced sarcomas arising from two pediatric cancer survivors. To assess the frequency of germline TP53 variants in SMNs, Sanger sequencing was performed to analyze germline TP53 in 37 pediatric cancer survivors from the Childhood Cancer Survivor Study (CCSS) without any history of a familial cancer predisposition syndrome but known to have developed SMNs. Results: WES revealed TP53 mutations involving p53's DNA-binding domain in both index cases, one of which was also present in the germline. The germline and somatic TP53- mutant variants were enriched in the transcriptomes for both sarcomas. Analysis of TP53- coding exons in germline specimens from the CCSS survivor cohort identified a G215C variant encoding an R72P amino acid substitution in 6 patients and a synonymous SNP A639G in 4 others, resulting in 10 of 37 evaluable patients (27%) harboring a germline TP53 variant. Conclusions: Currently, germline TP53 is not routinely assessed in patients with pediatric cancer. These data support the concept that identifying germline TP53 variants at the time a primary cancer is diagnosed may identify patients at high risk for SMN development, who could benefit from modified therapeutic strategies and/or intensive posttreatment monitoring. Clin Cancer Res; 23(7); 1852-61. ©2016 AACR . ©2016 American Association for Cancer Research.

  7. TP53 and FGFR3 Gene Mutation Assessment in Urine: Pilot Study for Bladder Cancer Diagnosis.

    Science.gov (United States)

    Noel, Nicolas; Couteau, Jerome; Maillet, Geraldine; Gobet, Françoise; D'Aloisio, Françoise; Minier, Christophe; Pfister, Christian

    2015-09-01

    To assess, in a prospective clinical research study, a new non-invasive and reliable test to accurately detect tumor protein 53 (TP53) and fibroblast growth factor receptor-3 (FGFR3) mutations in cells in urine. TP53 mutations were analyzed using the functional analysis of separated allele in yeast (FASAY) method, which allows functional analysis of the P53 protein, and FGFR3 mutations were assessed with the SNaPshot system, detecting the eight most frequent point-mutations of this gene. Chi-square test or Fisher's exact test were used to compare TP53 and FGFR3 mutations in the tumors according to tumor stage and grade. TP53 and FGFR3 mutations in bladder tumors increased and decreased respectively with increasing tumor stage and cellular grade (pFGFR3 mutations were observed in 76 tumors. The sensitivity for the detection of this type of mutation in urine was 46%, the specificity was 81%, the positive predictive value was 94% and the negative predictive value was 37%. Our original data confirmed the feasibility of TP53 and FGFR3 mutation detection in urine sediment. These measurements, together with urine cytology, may increase tumor detection. The sensitivity of the TP53/FGFR3 phenotype test in the urine was less than 50% and was not able to replace standard cystoscopy in the diagnosis of bladder tumors. Copyright© 2015 International Institute of Anticancer Research (Dr. John G. Delinassios), All rights reserved.

  8. Is TP53INP2 a critical regulator of muscle mass?

    Science.gov (United States)

    Sala, David; Zorzano, Antonio

    2015-05-01

    The main aim of this review is to summarize current knowledge of tumor protein p53-inducible nuclear protein 2 (TP53INP2) function and its role in skeletal muscle proteostasis. Autophagy is directly involved in the regulation of skeletal muscle mass. Thus, excessive autophagy is associated with several diseases that cause muscle wasting, and it promotes the loss of muscle protein. Furthermore, compromised autophagy also leads to muscle atrophy. In this regard, TP53INP2 activates autophagy in skeletal muscle, thus causing a reduction in muscle mass. Moreover, TP53INP2 gain of function enhances muscle wasting in a highly catabolic context such as in streptozotocin-induced diabetes. However, TP53INP2 is naturally repressed in human insulin resistance and in murine models of diabetes. These observations suggest that TP53INP2 repression would reduce muscle atrophy under conditions that favor protein loss in skeletal muscle. To date, there is no effective treatment for muscle wasting. Thus, the identification of new putative pharmacological targets to effectively treat this devastating condition is crucial. Given current knowledge about the role of TP53INP2 in skeletal muscle, this protein may be an optimal candidate to target for the prevention of muscle wasting.

  9. Cytotoxic and toxicogenomic effects of silibinin in bladder cancer cells with different TP53 status.

    Science.gov (United States)

    DE Oliveira, Daiane Teixeira; Savio, Andre Luiz Ventura; Marcondes, Joao Paulo DE Castro; Barros, Tatiane Martins; Barbosa, Ludmila Correia; Salvadori, Daisy Maria Favero; DA Silva, Glenda Nicioli

    2017-03-01

    Silibinin is a natural phenol found in the seeds of the milk thistle plant. Recent data have shown its effectiveness for preventing/treating bladder tumours. Therefore, in this study we investigated the cytotoxic and toxicogenetic activity of silibinin in bladder cancer cells with different TP53 statuses. Two bladder urothelial carcinoma cell lines were used: RT4 (wild-type TP53 gene) and T24 (mutated TP53 gene). Cell proliferation, clonogenic survival, apoptosis rates, genotoxicity and relative expression profile of FRAP/mTOR, FGFR3, AKT2 and DNMT1 genes and of miR100 and miR203 were evaluated. Silibinin promoted decreased proliferation and increased late apoptosis in TP53 mutated cells. Increased early apoptosis rates, primary DNA damage, and decrease of cell colonies in the clonogenic survival assay were detected in both RT4 and T24 cell lines. Down-regulation of FRAP/mTOR, AKT2, FGFR3, DNMT1 and miR100 expression occurred in RT4 cells. Modulation of miR203 was observed in both cell lines. In conclusion, despite the reduction of clone formation in both cell lines, the toxicogenomic effect of silibinin on FRAP/mTOR, AKT2, FGFR3, DNMT1 and miR100 was dependent on the TP53 status. Taken together, the data confirmed the role of silibinin as an antiproliferative compound, whose mechanism of action was related to the TP53 status.

  10. Childhood adrenocortical carcinoma as a sentinel cancer for detecting families with germline TP53 mutations.

    Science.gov (United States)

    Choong, S S; Latiff, Z A; Mohamed, M; Lim, L L W; Chen, K S; Vengidasan, L; Razali, H; Abdul Rahman, E J; Ariffin, H

    2012-12-01

    Li-Fraumeni syndrome (LFS) is a highly penetrant, autosomal dominant disorder where affected individuals carry a 50% risk of developing cancer before 30 years of age. It is most commonly associated with mutations in the tumour suppressor gene, TP53. Adrenocortical carcinoma (ACC) is a very rare paediatric cancer, and up to 80% of affected children are found to carry germline TP53 mutations. Hence, we propose using childhood ACC incidence as selection criteria for referral for TP53 mutation testing, independent of familial cancer history. Under the auspices of the Malaysian Society of Paediatric Haematology-Oncology, four eligible children diagnosed with ACC over a 30-month study period were referred for mutation testing. Three had a germline TP53 mutation. Subsequent TP53 testing in relatives showed two inherited mutations and one de novo mutation. These findings strongly support paediatric ACC as a useful sentinel cancer for initiating a germline TP53/LFS detection programme, particularly in countries where the lack of structured oncogenetic practice precludes the identification of families with LFS features. © 2012 John Wiley & Sons A/S. Published by Blackwell Publishing Ltd.

  11. Synthetic lethality between CCNE1 amplification and loss of BRCA1.

    Science.gov (United States)

    Etemadmoghadam, Dariush; Weir, Barbara A; Au-Yeung, George; Alsop, Kathryn; Mitchell, Gillian; George, Joshy; Davis, Sally; D'Andrea, Alan D; Simpson, Kaylene; Hahn, William C; Bowtell, David D L

    2013-11-26

    High-grade serous ovarian cancers (HGSCs) are characterized by a high frequency of TP53 mutations, BRCA1/2 inactivation, homologous recombination dysfunction, and widespread copy number changes. Cyclin E1 (CCNE1) gene amplification has been reported to occur independently of BRCA1/2 mutation, and it is associated with primary treatment failure and reduced patient survival. Insensitivity of CCNE1-amplified tumors to platinum cross-linking agents may be partly because of an intact BRCA1/2 pathway. Both BRCA1/2 dysfunction and CCNE1 amplification are known to promote genomic instability and tumor progression. These events may be mutually exclusive, because either change provides a path to tumor development, with no selective advantage to having both mutations. Using data from a genome-wide shRNA synthetic lethal screen, we show that BRCA1 and members of the ubiquitin pathway are selectively required in cancers that harbor CCNE1 amplification. Furthermore, we show specific sensitivity of CCNE1-amplified tumor cells to the proteasome inhibitor bortezomib. These findings provide an explanation for the observed mutual exclusivity of CCNE1 amplification and BRCA1/2 loss in HGSC and suggest a unique therapeutic approach for treatment-resistant CCNE1-amplified tumors.

  12. Transformation of the fallopian tube secretory epithelium leads to high-grade serous ovarian cancer in Brca;Tp53;Pten models.

    Science.gov (United States)

    Perets, Ruth; Wyant, Gregory A; Muto, Katherine W; Bijron, Jonathan G; Poole, Barish B; Chin, Kenneth T; Chen, Jin Yun H; Ohman, Anders W; Stepule, Corey D; Kwak, Soongu; Karst, Alison M; Hirsch, Michelle S; Setlur, Sunita R; Crum, Christopher P; Dinulescu, Daniela M; Drapkin, Ronny

    2013-12-09

    High-grade serous ovarian carcinoma presents significant clinical and therapeutic challenges. Although the traditional model of carcinogenesis has focused on the ovary as a tumor initiation site, recent studies suggest that there may be additional sites of origin outside the ovary, namely the secretory cells of the fallopian tube. Our study demonstrates that high-grade serous tumors can originate in fallopian tubal secretory epithelial cells and also establishes serous tubal intraepithelial carcinoma as the precursor lesion to high-grade serous ovarian and peritoneal carcinomas in animal models targeting the Brca, Tp53, and Pten genes. These findings offer an avenue to address clinically important questions that are critical for cancer prevention and early detection in women carrying BRCA1 and BRCA2 mutations. Copyright © 2013 Elsevier Inc. All rights reserved.

  13. Limited importance of the dominant-negative effect of TP53 missense mutations

    Directory of Open Access Journals (Sweden)

    Kordek Radzislaw

    2011-06-01

    Full Text Available Abstract Background Heterozygosity of TP53 missense mutations is related to the phenomenon of the dominant-negative effect (DNE. To estimate the importance of the DNE of TP53 mutations, we analysed the percentage of cancer cases showing a single heterozygous mutation of TP53 and searched for a cell line with a single heterozygous mutation of this gene. This approach was based on the knowledge that genes with evident DNE, such as EGFR and IDH1, represent nearly 100% of single heterozygous mutations in tumour specimens and cell lines. Methods Genetic analyses (LOH and sequencing performed for early and late passages of several cell lines originally described as showing single heterozygous TP53 mutations (H-318, G-16, PF-382, MOLT-13, ST-486 and LS-123. Statistical analysis of IARC TP53 and SANGER databases. Genetic analyses of N-RAS, FBXW7, PTEN and STR markers to test cross-contamination and cell line identity. Cell cloning, fluorescence-activated cell sorting and SSCP performed for the PF-382 cell line. Results A database study revealed TP53 single heterozygous mutations in 35% of in vivo (surgical and biopsy samples and only 10% of cultured cells (in vitro, although those numbers appeared to be overestimated. We deem that published in vivo TP53 mutation analyses are not as rigorous as studies in vitro, and we did not find any cell line showing a stable, single heterozygous mutation. G16, PF-382 and MOLT-13 cells harboured single heterozygous mutations temporarily. ST-486, H-318 and LS-123 cell lines were misclassified. Specific mutations, such as R175H, R273H, R273L or R273P, which are reported in the literature to exert a DNE, showed the lowest percentage of single heterozygous mutations in vitro (about 5%. Conclusion We suggest that the currently reported percentage of TP53 single heterozygous mutations in tumour samples and cancer cell lines is overestimated. Thus, the magnitude of the DNE of TP53 mutations is questionable. This scepticism

  14. Gaining insights into the codon usage patterns of TP53 gene across eight mammalian species.

    Directory of Open Access Journals (Sweden)

    Tarikul Huda Mazumder

    Full Text Available TP53 gene is known as the "guardian of the genome" as it plays a vital role in regulating cell cycle, cell proliferation, DNA damage repair, initiation of programmed cell death and suppressing tumor growth. Non uniform usage of synonymous codons for a specific amino acid during translation of protein known as codon usage bias (CUB is a unique property of the genome and shows species specific deviation. Analysis of codon usage bias with compositional dynamics of coding sequences has contributed to the better understanding of the molecular mechanism and the evolution of a particular gene. In this study, the complete nucleotide coding sequences of TP53 gene from eight different mammalian species were used for CUB analysis. Our results showed that the codon usage patterns in TP53 gene across different mammalian species has been influenced by GC bias particularly GC3 and a moderate bias exists in the codon usage of TP53 gene. Moreover, we observed that nature has highly favored the most over represented codon CTG for leucine amino acid but selected against the ATA codon for isoleucine in TP53 gene across all mammalian species during the course of evolution.

  15. Alterations of the TP53 Gene in Gastric and Esophageal Carcinogenesis

    Directory of Open Access Journals (Sweden)

    Marilanda Ferreira Bellini

    2012-01-01

    Full Text Available TP53 genes is one of more important tumor suppressor gene, which acts as a potent transcription factor with fundamental role in the maintenance of genetic stability. The development of esophageal and gastric cancers is a multistep process resulting in successive accumulation of genetic alterations that culminates in the malignant transformation. Thus, this study highlights the participation of the main genetic alterations of the TP53 gene in esophageal and gastric carcinogenesis. Among these changes, high frequency of TP53 mutations, loss of heterozygosity (LOH, overexpression of the p53 protein, and consequently loss of p53 function, which would be early events in esophageal and gastric cancers, as well as an important biomarker of the prognosis and treatment response. Furthermore, Single Nucleotide Polymorphisms (SNPs of TP53 have been implicated in the development and prognosis of several cancers, mainly TP53 codon 72 polymorphism whose role has been extensively studied in relation to susceptibility for esophageal and gastric cancer development.

  16. Are there low-penetrance TP53 Alleles? evidence from childhood adrenocortical tumors.

    Science.gov (United States)

    Varley, J M; McGown, G; Thorncroft, M; James, L A; Margison, G P; Forster, G; Evans, D G; Harris, M; Kelsey, A M; Birch, J M

    1999-10-01

    We have analyzed a panel of 14 cases of childhood adrenocortical tumors unselected for family history and have identified germline TP53 mutations in >80%, making this the highest known incidence of a germline mutation in a tumor-suppressor gene in any cancer. The spectrum of germline TP53 mutations detected is remarkably limited. Analysis of tumor tissue for loss of constitutional heterozygosity, with respect to the germline mutant allele and the occurrence of other somatic TP53 mutations, indicates complex sequences of genetic events in a number of tumors. None of the families had cancer histories that conformed to the criteria for Li-Fraumeni syndrome, but, in some families, we were able to demonstrate that the mutation had been inherited. In these families there were gene carriers unaffected in their 40s and 50s, and there were others with relatively late-onset cancers. These data provide evidence that certain TP53 alleles confer relatively low penetrance for predisposition to the development of cancer, and they imply that deleterious TP53 mutations may be more frequent in the population than has been estimated previously. Our findings have considerable implications for the clinical management of children with andrenocortical tumors and their parents, in terms of both genetic testing and the early detection and treatment of tumors.

  17. Ibrutinib for previously untreated and relapsed or refractory chronic lymphocytic leukaemia with TP53 aberrations

    DEFF Research Database (Denmark)

    Farooqui, Mohammed Z H; Valdez, Janet; Martyr, Sabrina

    2015-01-01

    BACKGROUND: Patients with chronic lymphocytic leukaemia (CLL) with TP53 aberrations respond poorly to first-line chemoimmunotherapy, resulting in early relapse and short survival. We investigated the safety and activity of ibrutinib in previously untreated and relapsed or refractory CLL with TP53...... enrolled 51 patients; 47 had CLL with deletion 17p13.1 and four carried a TP53 mutation in the absence of deletion 17p13.1. All patients had active disease requiring therapy. 35 enrolled patients had previously untreated CLL and 16 had relapsed or refractory disease. Median follow-up was 24 months (IQR 12.......9-27.0). 33 previously untreated patients and 15 patients with relapsed or refractory CLL were evaluable for response at 24 weeks. 32 (97%; 95% CI 86-100) of 33 previously untreated patients achieved an objective response, including partial response in 18 patients (55%) and partial response with lymphocytosis...

  18. TP53 mutations identify younger mantle cell lymphoma patients who do not benefit from intensive chemoimmunotherapy

    DEFF Research Database (Denmark)

    Eskelund, Christian W.; Dahl, Christina; Hansen, Jakob W.

    2017-01-01

    Despite recent advances in lymphoma treatment, mantle cell lymphoma (MCL) remains incurable, and we are still unable to identify patients who will not benefit from the current standard of care. Here, we explore the prognostic value of recurrent genetic aberrations in diagnostic bone marrow (BM......) specimens from 183 younger patients with MCL from the Nordic MCL2 and MCL3 trials, which represent current standard-of-care regimens. In the univariate model, mutations of TP53 (11%) and NOTCH1 (4%), and deletions of TP53 (16%) andCDKN2A(20%),weresignificantly associatedwithinferioroutcomes......(togetherwithMIPI, MIPI-c, blastoidmorphology, and Ki67 > 30%); however, inmultivariate analyses, only TP53 mutations (HR, 6.2; P mutations (HR, 6.9; P

  19. TP53 mutations in clinically normal mucosa adjacent to oral carcinomas

    DEFF Research Database (Denmark)

    Thode, C; Bilde, A; Von Buchwald, C

    2010-01-01

    BACKGROUND: The tumour-suppressor protein p53 often accumulates in histologically normal epithelium adjacent to oral squamous cell carcinomas (OSCC). We investigated whether this was associated with mutations in TP53, the gene for p53, and might implicate impending malignancy. METHODS: Specimens...... products were separated by denatured gradient gel electrophoresis. Fragments with a deviant DGEE pattern were sequenced. RESULTS: TP53 mutations were found in six of 18 tumours. Fourteen specimens contained histologically normal mucosa adjacent to the tumour; 13 of these showed small clusters of p53...... positive cells. Seven specimens contained both histological normal and dysplastic epithelial tissues adjacent to the tumour. A TP53 mutation was found in only one specimen; this mutation appeared in the normal mucosa, the adjacent tumour, and the epithelial dysplasia. CONCLUSION: We found that upregulation...

  20. Two TP53 germline mutations in a classical Li-Fraumeni syndrome family.

    Science.gov (United States)

    van Hest, Liselotte P; Ruijs, Mariëlle W G; Wagner, Anja; van der Meer, Conny A; Verhoef, Senno; van't Veer, Laura J; Meijers-Heijboer, Hanne

    2007-01-01

    Li-Fraumeni syndrome (LFS) is an autosomal dominantly inherited cancer predisposition syndrome characterized by a combination of tumors including sarcoma, breast cancer, brain tumors, adrenocortical carcinoma and leukemia. Germline mutations in the tumor suppressor gene TP53 are associated with LFS. We present a family with LFS in which initially a novel germline TP53 intron 5 splice site mutation was found. A second germline TP53 mutation, the exon 7 Asn235Ser (704A-->G) mutation, was detected in this family through pre-symptomatic DNA testing. This latter mutation has been reported repeatedly in the literature as a pathogenic mutation involved in LFS. We provide evidence for pathogenicity of the novel intron 5 splice site mutation, whereas this evidence is lacking for the exon 7 Asn235Ser (704A-->G) mutation. Our findings emphasize the importance of performing additional tests in case of germline sequence variants with uncertain functional effects.

  1. Association of the germline TP53 R337H mutation with breast cancer in southern Brazil

    Directory of Open Access Journals (Sweden)

    Srivastava Kumar

    2008-12-01

    Full Text Available Abstract Background The germline TP53-R337H mutation is strongly associated with pediatric adrenocortical tumors (ACT in southern Brazil; it has low penetrance and limited tissue specificity in most families and therefore is not associated with Li-Fraumeni syndrome. However, other tumor types, mainly breast cancer, have been observed in carriers of several unrelated kindreds, raising the possibility that the R337H mutation may also contribute to breast tumorigenesis in a genetic background-specific context. Methods We conducted a case-control study to determine the prevalence of the R337H mutation by sequencing TP53 exon 10 in 123 women with breast cancer and 223 age- and sex-matched control subjects from southern Brazil. Fisher's test was used to compare the prevalence of the R337H. Results The R337H mutation was found in three patients but in none of the controls (p = 0.0442. Among the carriers, two had familial history of cancer meeting the Li-Fraumeni-like criteria. Remarkably, tumors in each of these three cases underwent loss of heterozygosity by eliminating the mutant TP53 allele rather than the wild-type allele. Polymorphisms were identified within the TP53 (R72P and Ins16 and MDM2 (SNP309 genes that may further diminish TP53 tumor suppressor activity. Conclusion These results demonstrate that the R337H mutation can significantly increase the risk of breast cancer in carriers, which likely depends on additional cooperating genetic factors. These findings are also important for understanding how low-penetrant mutant TP53 alleles can differentially influence tumor susceptibility.

  2. Low penetrance susceptibility to glioma is caused by the TP53 variant rs78378222.

    Science.gov (United States)

    Enciso-Mora, V; Hosking, F J; Di Stefano, A L; Zelenika, D; Shete, S; Broderick, P; Idbaih, A; Delattre, J-Y; Hoang-Xuan, K; Marie, Y; Labussière, M; Alentorn, A; Ciccarino, P; Rossetto, M; Armstrong, G; Liu, Y; Gousias, K; Schramm, J; Lau, C; Hepworth, S J; Schoemaker, M; Strauch, K; Müller-Nurasyid, M; Schreiber, S; Franke, A; Moebus, S; Eisele, L; Swerdlow, A; Simon, M; Bondy, M; Lathrop, M; Sanson, M; Houlston, R S

    2013-05-28

    Most of the heritable risk of glioma is presently unaccounted for by mutations in known genes. In addition to rare inactivating germline mutations in TP53 causing glioma in the context of the Li-Fraumeni syndrome, polymorphic variation in TP53 may also contribute to the risk of developing glioma. To comprehensively evaluate the impact of variation in TP53 on risk, we analysed 23 tagSNPs and imputed 2377 unobserved genotypes in four series totaling 4147 glioma cases and 7435 controls. The strongest validated association signal was shown by the imputed single-nucleotide polymorphism (SNP) rs78378222 (P=6.86 × 10(-24), minor allele frequency ~0.013). Confirmatory genotyping confirmed the high quality of the imputation. The association between rs78378222 and risk was seen for both glioblastoma multiforme (GBM) and non-GBM tumours. We comprehensively examined the relationship between rs78378222 and overall survival in two of the case series totaling 1699 individuals. Despite employing statistical tests sensitive to the detection of differences in early survival, no association was shown. Our data provided strong validation of rs78378222 as a risk factor for glioma but do not support the tenet that the polymorphism being a clinically useful prognostic marker. Acquired TP53 inactivation is a common feature of glioma. As rs78378222 changes the polyadenylation signal of TP53 leading to impaired 3'-end processing of TP53 mRNA, the SNP has strong plausibility for being directly functional contributing to the aetiological basis of glioma.

  3. TP53 mutations in human cancers: functional selection and impact on cancer prognosis and outcomes.

    Science.gov (United States)

    Petitjean, A; Achatz, M I W; Borresen-Dale, A L; Hainaut, P; Olivier, M

    2007-04-02

    A large amount of data is available on the functional impact of missense mutations in TP53 and on mutation patterns in many different cancers. New data on mutant p53 protein function, cancer phenotype and prognosis have recently been integrated in the International Agency for Research on Cancer TP53 database (http://www-p53.iarc.fr/). Based on these data, we summarize here current knowledge on the respective roles of mutagenesis and biological selection of mutations with specific functional characteristic in shaping the patterns and phenotypes of mutations observed in human cancers. The main conclusion is that intrinsic mutagenicity rates, loss of transactivation activities, and to a lesser extent, dominant-negative activities are the main driving forces that determine TP53 mutation patterns and influence tumor phenotype. In contrast, current experimental data on the acquisition of oncogenic activities (gain of function) by p53 mutants are too scarce and heterogenous to assess whether this property has an impact on tumor development and outcome. In the case of inherited TP53 mutations causing Li-Fraumeni and related syndromes, the age at onset of some tumor types is in direct relation with the degree of loss of transactivation capacity of missense mutations. Finally, studies on large case series demonstrate that TP53 mutations are independent markers of bad prognosis in breast and several other cancers, and that the exact type and position of the mutation influences disease outcome. Further studies are needed to determine how TP53 haplotypes or loss of alleles interact with mutations to modulate their impact on cancer development and prognosis.

  4. Genetic evaluation based on family history and Her2 status correctly identifies TP53 mutations in very early onset breast cancer cases.

    Science.gov (United States)

    Fostira, F; Konstantopoulou, I; Mavroudis, D; Tryfonopoulos, D; Yannoukakos, D; Voutsinas, G E

    2015-04-01

    Currently, hereditary breast cancer is being attributed to more than 20 genes of differing penetrance. Although BRCA1 and BRCA2 are still the genes of reference for breast cancer susceptibility, extreme breast cancer phenotypes may be the result of deleterious alleles of other genes. Here, we report three families with early-onset breast cancer that were initially referred for BRCA1/BRCA2 genetic testing. They were diagnosed with breast cancer at an extraordinarily early age. On the basis of their extensive family history, which included multiple cancer types, and their Her2 status, they were suspected for Li-Fraumeni syndrome. Indeed, all three probands were found to harbor TP53 tumor suppressor gene mutations. These included p.C275X, described here for the first time, as well as p.R213X and p.Y220C, which have been described in the past. Our conclusion is that decisions on genetic analysis for inherited early onset breast cancer should always be based on detailed pedigree information, combined with Her2 status. © 2014 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  5. Mutations in TP53 and CTNNB1 in Relation to Hepatitis B and C Infections in Hepatocellular Carcinomas from Thailand

    Directory of Open Access Journals (Sweden)

    Olivier Galy

    2011-01-01

    Full Text Available Hepatocellular carcinoma (HCC may develop according to two major pathways, one involving HBV infection and TP53 mutation and the other characterized by HCV infection and CTNNB1 mutation. We have investigated HBV/HCV infections and TP53/CTNNB1 mutations in 26 HCC patients from Thailand. HBV DNA (genotype B or C was detected in 19 (73% of the cases, including 5 occult infections and 3 coinfections with HCV. TP53 and CTNNB1 mutations were not mutually exclusive, and most of TP53 mutations were R249S, suggesting a significant impact of aflatoxin-induced mutagenesis in HCC development.

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

    Science.gov (United States)

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

    1991-01-01

    The TP53 gene is considered to be a negative regulator of cell growth whose inactivation is an important step in the development or progression of malignancies. Recently, germ line TP53 mutations have been detected in a familial cancer syndrome, the dominantly inherited Li-Fraumeni syndrome. Using single strand conformation polymorphism analysis of PCR products, we looked for TP53 mutations in DNA of patients with Fanconi anemia, an autosomal recessive disease characterized by increased predisposition to neoplasia. We did not find any TP53 mutation in 13 patients, suggesting that this tumor suppressor gene is not directly involved in the cancer susceptibility observed in Fanconi's anemia.

  7. Neural network predicts sequence of TP53 gene based on DNA chip

    DEFF Research Database (Denmark)

    Spicker, J.S.; Wikman, F.; Lu, M.L.

    2002-01-01

    We have trained an artificial neural network to predict the sequence of the human TP53 tumor suppressor gene based on a p53 GeneChip. The trained neural network uses as input the fluorescence intensities of DNA hybridized to oligonucleotides on the surface of the chip and makes between zero...

  8. Deletions linked to TP53 loss drive cancer through p53-independent mechanisms.

    Science.gov (United States)

    Liu, Yu; Chen, Chong; Xu, Zhengmin; Scuoppo, Claudio; Rillahan, Cory D; Gao, Jianjiong; Spitzer, Barbara; Bosbach, Benedikt; Kastenhuber, Edward R; Baslan, Timour; Ackermann, Sarah; Cheng, Lihua; Wang, Qingguo; Niu, Ting; Schultz, Nikolaus; Levine, Ross L; Mills, Alea A; Lowe, Scott W

    2016-03-24

    Mutations disabling the TP53 tumour suppressor gene represent the most frequent events in human cancer and typically occur through a two-hit mechanism involving a missense mutation in one allele and a 'loss of heterozygosity' deletion encompassing the other. While TP53 missense mutations can also contribute gain-of-function activities that impact tumour progression, it remains unclear whether the deletion event, which frequently includes many genes, impacts tumorigenesis beyond TP53 loss alone. Here we show that somatic heterozygous deletion of mouse chromosome 11B3, a 4-megabase region syntenic to human 17p13.1, produces a greater effect on lymphoma and leukaemia development than Trp53 deletion. Mechanistically, the effect of 11B3 loss on tumorigenesis involves co-deleted genes such as Eif5a and Alox15b (also known as Alox8), the suppression of which cooperates with Trp53 loss to produce more aggressive disease. Our results imply that the selective advantage produced by human chromosome 17p deletion reflects the combined impact of TP53 loss and the reduced dosage of linked tumour suppressor genes.

  9. Deletions linked to TP53 loss drive cancer through p53–independent mechanisms

    Science.gov (United States)

    Xu, Zhengmin; Scuoppo, Claudio; Rillahan, Cory D.; Gao, Jianjiong; Spitzer, Barbara; Bosbach, Benedikt; Kastenhuber, Edward R.; Baslan, Timour; Ackermann, Sarah; Cheng, Lihua; Wang, Qingguo; Niu, Ting; Schultz, Nikolaus; Levine, Ross L.; Mills, Alea A.; Lowe, Scott W.

    2016-01-01

    Mutations disabling the TP53 tumour suppressor gene represent the most frequent events in human cancer and typically occur through a two-hit mechanism involving a missense mutation in one allele and a ‘loss of heterozygosity’ deletion encompassing the other. While TP53 missense mutations can also contribute gain-of-function activities that impact tumour progression, it remains unclear whether the deletion event, which frequently includes many genes, impacts tumorigenesis beyond TP53 loss alone. Here we show that somatic heterozygous deletion of mouse chromosome 11B3, a 4-megabase region syntenic to human 17p13.1, produces a greater effect on lymphoma and leukaemia development than Trp53 deletion. Mechanistically, the effect of 11B3 loss on tumorigenesis involves co-deleted genes such as Eif5a and Alox15b (also known as Alox8), the suppression of which cooperates with Trp53 loss to produce more aggressive disease. Our results imply that the selective advantage produced by human chromosome 17p deletion reflects the combined impact of TP53 loss and the reduced dosage of linked tumour suppressor genes. PMID:26982726

  10. K-rascodon 12 and not TP53mutations are predominant in ...

    African Journals Online (AJOL)

    and 500 000 die from the disease annually.[1] Among Eurasian countries ... via epigenetic modifications such as DNA methylation and histone acetylation. Rapidly ... oncogene and TP53 tumour suppressor gene mutations are among the most common genetic alterations detected in advanced colorectal tumours. Objective.

  11. TP53 GENE MUTATIONS – FROM GUARDIAN OF THE GENOME TO ONCOGENE

    Directory of Open Access Journals (Sweden)

    Petar Babović

    2010-03-01

    Full Text Available TP53 tumor suppressor gene mutations are the most frequent genetic alterations in human cancer affecting a specific gene. The occurrence of TP53 mutations is considerably influenced by cancer-initiating events, such as DNA damage, the aftermath of which is the promotion of cancer development through the loss of anti-proliferative activities, including apoptosis and cellular senescence. Over 27.000 TP53 gene mutations have been discovered and found in more than 50% of human cancers. The most frequent alterations are the point mutations with a single base substitution in gene segment encoding for DNA-binding domaine of p53 molecule, leading to the production of mutant protein that differs from the wild-type protein by one amino acid (missense mutations usually causing the change in tertiary structure of gene product, thus preventing p53 to bind to DNA and activate transcription of target genes. The result of the mutations may also be the proteins with new, abnormal functions, and the ability to modulate expression of genes responsible for neoangiogenesis, resistance to chemotherapeutics and prevention of tumor initiation and promotion. In such circumstances, not only the mutant TP53 loses its tumor suppressive function, but acquires oncogenic potential and becomes an active participant in the neoplastic transformation of the cell.Vast heterogeneity of mutations and methodological approaches in p53 status assessment represent the main difficulties in rapid and effective integration of basic p53 research into clinical practice.

  12. Single nucleotide polymorphisms in the TP53 region and susceptibility to invasive epithelial ovarian cancer

    DEFF Research Database (Denmark)

    Schildkraut, Joellen M; Goode, Ellen L; Clyde, Merlise A

    2009-01-01

    The p53 protein is critical for multiple cellular functions including cell growth and DNA repair. We assessed whether polymorphisms in the region encoding TP53 were associated with risk of invasive ovarian cancer. The study population includes a total of 5,206 invasive ovarian cancer cases (2,829...

  13. The Relationship between TP53 Gene Status and Carboxylesterase 2 Expression in Human Colorectal Cancer

    Directory of Open Access Journals (Sweden)

    Momoko Ishimine

    2018-01-01

    Full Text Available Irinotecan (CPT-11 is an anticancer prodrug that is activated by the carboxylesterase CES2 and has been approved for the treatment of many types of solid tumors, including colorectal cancer. Recent studies with cell lines show that CES2 expression is regulated by the tumor suppressor protein p53. However, clinical evidence for this regulatory mechanism in cancer is lacking. In this study, we examined the relationship between TP53 gene status and CES2 expression in human colorectal cancer. Most colorectal cancer specimens (70%; 26 of 37 showed lower CES2 mRNA levels (≥1.5-fold lower than the adjacent normal tissue, and only 30% (12 of 37 showed similar (<1.5-fold lower or higher CES2 mRNA levels. However, TP53 gene sequencing revealed no relationship between CES2 downregulation and TP53 mutational status. Moreover, while colorectal cancer cells expressing wild-type p53 exhibited p53-dependent upregulation of CES2, PRIMA-1MET, a drug that restores the transcriptional activity of mutant p53, failed to upregulate CES2 expression in cells with TP53 missense mutations. These results, taken together, suggest that CES2 mRNA expression is decreased in human colorectal cancer independently of p53.

  14. Two TP53 germline mutations in a classical Li-Fraumeni syndrome family

    NARCIS (Netherlands)

    van Hest, Liselotte P.; Ruijs, Mariëlle W. G.; Wagner, Anja; van der Meer, Conny A.; Verhoef, Senno; van 't Veer, Laura J.; Meijers-Heijboer, Hanne

    2007-01-01

    Li-Fraumeni syndrome (LFS) is an autosomal dominantly inherited cancer predisposition syndrome characterized by a combination of tumors including sarcoma, breast cancer, brain tumors, adrenocortical carcinoma and leukemia. Germline mutations in the tumor suppressor gene TP53 are associated with LFS.

  15. TP53 Codon 72 Polymorphism and P53 Protein Expression in Colorectal Cancer Specimens in Isfahan

    Directory of Open Access Journals (Sweden)

    Mehdi Nikbahkt Dastjerdi

    2011-02-01

    Full Text Available The TP53 tumor suppressor gene plays important roles in genomic stability. A common polymorphism at codon 72 of TP53 gene has been associated with increased risk for many human cancers. The p53 protein is expressed in colorectal cancer, but the reported prevalence of its expression varies widely. In the present study, the p53 protein expression in different genotypes of its codon 72 , was investigated. We undertook a case-control study on 250 controls and 250 paraffin block specimens of sporadic colorectal adenocarcinomas from the city of Isfahan. PCR amplification of TP53 codon 72 polymorphism: TP53 codon 72 genotypes were detected by PCR using specific primer pairs for amplifying the proline or the arginine Alleles. The PCR reaction was done separately for each of the two polymorphic variants. The amplified products were subjected to electrophoresis on 1% agarose gel in 1× TBE buffer and visualized on a transilluminator using ethidium bromide. Immunohistochemical Staining: We evaluated the expression patterns of p53 protein, as potential prognostic marker in colorectal cancer specimens by immunohistochemical staining. Statistical analyses: The χ2-test was used to assess the significance of any difference in the prevalence of TP53 codon 72 polymorphism between colorectal cancer patients and controls. The odds ratio and 95% CI (confidence intervals was used as a measure of the strength of the association. Statistical significance level was set to P≤0.05. In control samples, the genotype distribution for TP53 polymorphism showed 30.4%, 45.2% and 24.4% for the arginine/arginine, arginine/proline and proline/proline genotypes, respectively. Allelic frequencies corresponded to 0.663 for the arginine allele and 0.338 for the proline allele. In the cancer group 38.8% of the cases were arginine/arginine, 40.4% were arginine/proline and 20.8% were proline/proline. The corresponding frequencies were 0.590 for the arginine allele and 0.410 for the

  16. TP53 codon 72 polymorphism as a risk factor for cardiovascular disease in a Brazilian population

    Directory of Open Access Journals (Sweden)

    M.A.C. Smith

    2007-11-01

    Full Text Available TP53, a tumor suppressor gene, has a critical role in cell cycle, apoptosis and cell senescence and participates in many crucial physiological and pathological processes. Identification of TP53 polymorphism in older people and age-related diseases may provide an understanding of its physiology and pathophysiological role as well as risk factors for complex diseases. TP53 codon 72 (TP53:72 polymorphism was investigated in 383 individuals aged 66 to 97 years in a cohort from a Brazilian Elderly Longitudinal Study. We investigated allele frequency, genotype distribution and allele association with morbidities such as cardiovascular disease, type II diabetes, obesity, neoplasia, low cognitive level (dementia, and depression. We also determined the association of this polymorphism with serum lipid fractions and urea, creatinine, albumin, fasting glucose, and glycated hemoglobin levels. DNA was isolated from blood cells, amplified by PCR using sense 5'-TTGCCGTCCCAAGCAATGGATGA-3' and antisense 5'-TCTGGGAAGGGACAGAAGATGAC-3' primers and digested with the BstUI enzyme. This polymorphism is within exon 4 at nucleotide residue 347. Descriptive statistics, logistic regression analysis and Student t-test using the multiple comparison test were used. Allele frequencies, R (Arg = 0.69 and P (Pro = 0.31, were similar to other populations. Genotype distributions were within Hardy-Weinberg equilibrium. This polymorphism did not show significant association with any age-related disease or serum variables. However, R allele carriers showed lower HDL levels and a higher frequency of cardiovascular disease than P allele subjects. These findings may help to elucidate the physiopathological role of TP53:72 polymorphism in Brazilian elderly people.

  17. KRAS and TP53 mutations in bronchoscopy samples from former lung cancer patients.

    Science.gov (United States)

    Gao, Weimin; Jin, Jide; Yin, Jinling; Land, Stephanie; Gaither-Davis, Autumn; Christie, Neil; Luketich, James D; Siegfried, Jill M; Keohavong, Phouthone

    2017-02-01

    Mutations in the KRAS and TP53 genes have been found frequently in lung tumors and specimens from individuals at high risk for lung cancer and have been suggested as predictive markers for lung cancer. In order to assess the prognostic value of these two genes' mutations in lung cancer recurrence, we analyzed mutations in codon 12 of the KRAS gene and in hotspot codons of the TP53 gene in 176 bronchial biopsies obtained from 77 former lung cancer patients. Forty-seven patients (61.0%) showed mutations, including 35/77 (45.5%) in the KRAS gene and 25/77 (32.5%) in the TP53 gene, among them 13/77 (16.9%) had mutations in both genes. When grouped according to past or current smoking status, a higher proportion of current smokers showed mutations, in particular those in the TP53 gene (P = 0.07), compared with ex-smokers. These mutations were found in both abnormal lesions (8/20 or 40%) and histologically normal tissues (70/156 or 44.9%) (P = 0.812). They consisted primarily of G to A transition and G to T transversion in both the KRAS (41/56 or 73.2%) and TP53 (24/34 or 70.6%) genes, consistent with mutations found in lung tumors of smoking lung cancer patients. Overall, recurrence-free survival (RFS) among all subjects could be explained by age at diagnosis, tumor stage, tumor subtype, and smoking (P lung cancer patients. However, the presence of mutation of bronchial biopsies was not significantly associated with a shorter RFS time. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

  18. EstimatingTP53Mutation Carrier Probability in Families with Li-Fraumeni Syndrome Using LFSPRO.

    Science.gov (United States)

    Peng, Gang; Bojadzieva, Jasmina; Ballinger, Mandy L; Li, Jialu; Blackford, Amanda L; Mai, Phuong L; Savage, Sharon A; Thomas, David M; Strong, Louise C; Wang, Wenyi

    2017-06-01

    Background: Li-Fraumeni syndrome (LFS) is associated with germline TP53 mutations and a very high lifetime cancer risk. Algorithms that assess a patient's risk of inherited cancer predisposition are often used in clinical counseling. The existing LFS criteria have limitations, suggesting the need for an advanced prediction tool to support clinical decision making for TP53 mutation testing and LFS management. Methods: Based on a Mendelian model, LFSPRO estimates TP53 mutation probability through the Elston-Stewart algorithm and consequently estimates future risk of cancer. With independent datasets of 1,353 tested individuals from 867 families, we evaluated the prediction performance of LFSPRO. Results: LFSPRO accurately predicted TP53 mutation carriers in a pediatric sarcoma cohort from MD Anderson Cancer Center in the United States, the observed to expected ratio (OE) = 1.35 (95% confidence interval, 0.99-1.80); area under the receiver operating characteristic curve (AUC) = 0.85 (0.75-0.93); a population-based sarcoma cohort from the International Sarcoma Kindred Study in Australia, OE = 1.62 (1.03-2.55); AUC = 0.67 (0.54-0.79); and the NCI LFS study cohort, OE = 1.28 (1.17-1.39); AUC = 0.82 (0.78-0.86). LFSPRO also showed higher sensitivity and specificity than the classic LFS and Chompret criteria. LFSPRO is freely available through the R packages LFSPRO and BayesMendel. Conclusions: LFSPRO shows good performance in predicting TP53 mutations in individuals and families in varied situations. Impact: LFSPRO is more broadly applicable than the current clinical criteria and may improve clinical management for individuals and families with LFS. Cancer Epidemiol Biomarkers Prev; 26(6); 837-44. ©2017 AACR . ©2017 American Association for Cancer Research.

  19. TP53 mutations in low-risk myelodysplastic syndromes with del(5q) predict disease progression.

    Science.gov (United States)

    Jädersten, Martin; Saft, Leonie; Smith, Alexander; Kulasekararaj, Austin; Pomplun, Sabine; Göhring, Gudrun; Hedlund, Anette; Hast, Robert; Schlegelberger, Brigitte; Porwit, Anna; Hellström-Lindberg, Eva; Mufti, Ghulam J

    2011-05-20

    To determine the frequency of TP53 mutations and the level of p53 protein expression by immunohistochemistry (IHC) in low-risk myelodysplastic syndromes (MDS) with del(5q) and to assess their impact on disease progression. Pre- and postprogression bone marrow (BM) samples from 55 consecutive patients with International Prognostic Scoring System low risk (n = 32) or intermediate-1 risk (n = 23) were studied by next-generation sequencing of TP53. IHC for p53 was performed on 148 sequential BM samples. TP53 mutations with a median clone size of 11% (range, 1% to 54%) were detected in 10 patients (18%) already at an early phase of the disease. Mutations were equally common in low-risk and intermediate-1-risk patients and were associated with evolution to acute myeloid leukemia (5 of 10 v 7 of 45; P = .045). Nine of 10 patients carrying mutations showed more than 2% BM progenitors with strong p53 staining. The probability of a complete cytogenetic response to lenalidomide was lower in mutated patients (0 of 7 v 12 of 24; P = .024). By using sensitive deep-sequencing technology, we demonstrated that TP53 mutated populations may occur at an early disease stage in almost a fifth of low-risk MDS patients with del(5q). Importantly, mutations were present years before disease progression and were associated with an increased risk of leukemic evolution. TP53 mutations could not be predicted by common clinical features but were associated with p53 overexpression. Our findings indicate a previously unrecognized heterogeneity of the disease which may significantly affect clinical decision making.

  20. Extremely high Tp53 mutation load in esophageal squamous cell carcinoma in Golestan Province, Iran.

    Directory of Open Access Journals (Sweden)

    Behnoush Abedi-Ardekani

    Full Text Available BACKGROUND: Golestan Province in northeastern Iran has one of the highest incidences of esophageal squamous cell carcinoma (ESCC in the world with rates over 50 per 100,000 person-years in both sexes. We have analyzed TP53 mutation patterns in tumors from this high-risk geographic area in search of clues to the mutagenic processes involved in causing ESCC. METHODOLOGY/PRINCIPAL FINDINGS: Biopsies of 119 confirmed ESCC tumor tissue from subjects enrolled in a case-control study conducted in Golestan Province were analyzed by direct sequencing of TP53 exons 2 through 11. Immunohistochemical staining for p53 was carried out using two monoclonal antibodies, DO7 and 1801. A total of 120 TP53 mutations were detected in 107/119 cases (89.9%, including 11 patients with double or triple mutations. The mutation pattern was heterogeneous with infrequent mutations at common TP53 "hotspots" but frequent transversions potentially attributable to environmental carcinogens forming bulky DNA adducts, including 40% at bases known as site of mutagenesis by polycyclic aromatic hydrocarbons (PAHs. Mutations showed different patterns according to the reported temperature of tea consumption, but no variation was observed in relation to ethnicity, tobacco or opium use, and alcoholic beverage consumption or urban versus rural residence. CONCLUSION/SIGNIFICANCE: ESCC tumors in people from Golestan Province show the highest rate of TP53 mutations ever reported in any cancer anywhere. The heterogeneous mutation pattern is highly suggestive of a causative role for multiple environmental carcinogens, including PAHs. The temperature and composition of tea may also influence mutagenesis.

  1. TP53 mutation and human papilloma virus status of oral squamous cell carcinomas in young adult patients

    NARCIS (Netherlands)

    Braakhuis, B.J.M.; Rietbergen, M.M.; Buijze, M.; Snijders, P.J.F.; Bloemena, E.; Brakenhoff, R.H.; Leemans, C.R.

    2014-01-01

    Objective Little is known about the molecular carcinogenesis of oral squamous cell carcinoma (OSCC) in young adult patients. The aim of this study was to investigate the detailed TP53 mutation and human papilloma virus (HPV) status of OSCC in patients, younger than 45 years. Methods TP53 mutations

  2. Human papillomavirus type 16 and TP53 mutation in oral cancer: matched analysis of the IARC multicenter study.

    NARCIS (Netherlands)

    Dai, M; Clifford, GM; Calvez, F le; Castellsague, X; Snijders, P.J.F.; Pawlita, M; Herrero, R; Hainaut, P; Franceschi, S

    2004-01-01

    TP53 mutations were analyzed in 35 human papillomavirus (HPV) type 16 DNA-positive cancers of the oral cavity and oropharynx and in 35 HPV DNA-negative cancers matched by subsite, country, sex, age, and tobacco and alcohol consumption. Wild-type TP53 was found more frequently in cancer specimens

  3. A meta-analysis of the relationship between FGFR3 and TP53 mutations in bladder cancer

    National Research Council Canada - National Science Library

    Neuzillet, Yann; Paoletti, Xavier; Ouerhani, Slah; Mongiat-Artus, Pierre; Soliman, Hany; de The, Hugues; Sibony, Mathilde; Denoux, Yves; Molinie, Vincent; Herault, Aurélie; Lepage, May-Linda; Maille, Pascale; Renou, Audrey; Vordos, Dimitri; Abbou, Claude-Clément; Bakkar, Ashraf; Asselain, Bernard; Kourda, Nadia; El Gaaied, Amel; Leroy, Karen; Laplanche, Agnès; Benhamou, Simone; Lebret, Thierry; Allory, Yves; Radvanyi, François

    2012-01-01

    TP53 and FGFR3 mutations are the most common mutations in bladder cancers. FGFR3 mutations are most frequent in low-grade low-stage tumours, whereas TP53 mutations are most frequent in high-grade high-stage tumours...

  4. Structural profiles of TP53 gene mutations predict clinical outcome in diffuse large B-cell lymphoma

    DEFF Research Database (Denmark)

    Young, Ken H; Leroy, Karen; Møller, Michael Boe

    2008-01-01

    The purpose of this study is to correlate the presence of TP53 gene mutations with the clinical outcome of a cohort of patients with diffuse large B-cell lymphoma (DLBCL) assembled from 12 medical centers. TP53 mutations were identified in 102 of 477 patients and the overall survival (OS) of pati...

  5. Rhabdomyosarcoma-associated renal cell carcinoma: a link with constitutional Tp53 mutation.

    LENUS (Irish Health Repository)

    Curry, Sarah

    2012-02-01

    The 2004 World Health Organization classification includes the new entity "neuroblastoma-associated renal cell carcinoma." The pathogenetic link between these entities is unknown as yet. The patient reported herein developed renal cell carcinoma after anaplastic embryonal rhabdomyosarcoma, a previously unknown association. The 2nd malignancy developed very soon after the 1st one, prompting concern for inherent cancer predisposition rather than a therapy-induced 2nd malignancy. A variety of features raised suspicion for Tp53 mutation, and indeed a pathogenic germline Tp53 mutation was identified in this child, despite a negative family history for Li-Fraumeni syndrome. Consideration of underlying predisposition is advocated in the context of rapid evolution of 2nd childhood malignancy.

  6. Dual Pten/Tp53 Suppression Promotes Sarcoma Progression by Activating Notch Signaling

    OpenAIRE

    Guijarro, Maria V.; Dahiya, Sonika; Danielson, Laura S.; Miguel F. Segura; Vales-Lara, Frances M.; Menendez, Silvia; Popiolek, Dorota; Mittal, Khushbakhat; Wei, Jian Jun; Zavadil, Jiri; Cordon-Cardo, Carlos; Pandolfi, Pier Paolo; Hernando, Eva

    2013-01-01

    Soft tissue sarcomas are a heterogeneous group of tumors associated with poor clinical outcome. Although a subset of soft tissue sarcomas is characterized by simple karyotypes and recurrent chromosomal translocations, the mechanisms driving cytogenetically complex sarcomas are largely unknown. Clinical evidence led us to partially inactivate Pten and Tp53 in the smooth muscle lineage of mice, which developed high-grade undifferentiated pleomorphic sarcomas, leiomyosarcomas, and carcinosarcoma...

  7. Radiosensitivity and TP 53, EGFR amplification and LOH10 analysis of primary glioma cell cultures

    Energy Technology Data Exchange (ETDEWEB)

    Gerlach, B. [Dept. of Radiation Oncology, VU Univ. Medical Center, Amsterdam (Netherlands); Dept. of Radiation Oncology, Univ. of Duesseldorf (Germany); Harder, A.H.; Slotman, B.J.; Sminia, P. [Dept. of Radiation Oncology, VU Univ. Medical Center, Amsterdam (Netherlands); Hulsebos, T.J.M. [Dept. of Human Genetics, Academic Medical Center, Amsterdam (Netherlands); Leenstra, S. [Dept. of Neurosurgery, Academic Medical Center, Amsterdam (Netherlands); Peter Vandertop, W. [Dept. of Neurosurgery, VU Univ. Medical Center, Amsterdam (Netherlands); Hartmann, K.A. [Dept. of Radiation Oncology, Univ. of Duesseldorf (Germany)

    2002-09-01

    Aim: Determination of in-vitro radiosensitivity and genetic alterations of cell cultures derived from human glioma biopsy tissue and established glioma cell lines. Material and Methods: Fresh brain tumor specimens of six patients were processed to early passage cell cultures. In addition the cell lines D 384 and Gli 6 were used. Cell cultures were irradiated with doses from 2 to 10 Gy. Following irradiation, cell survival was determined by clonogenic assay and survival curves were generated. The surviving fractions after 2 Gy (SF2) and 4 Gy (SF4) were used as radiosensitivity parameters. Genetic analysis included determination of the mutational and loss of heterozygosity (LOH) status of TP 53 (exons 5-8), the LOH 10- and epidermal growth factor receptor gene (EGFR) amplification status. Results: The SF2 and SF4 values ranged from 0.54 to 0.88 (mean: 0.70) and from 0.13 to 0.52 (mean: 0.32), respectively. Genetic alterations were found in the Gli 6 cell line and in two primary cell cultures. The genetic profile of Gli 6 showed LOH but no TP 53 mutation, complete LOH 10 and no EGFR amplification. The VU 15 cell culture showed TP 53 mutation but no LOH 10 or EGFR amplification, while VU 24 showed incomplete LOH 10, EGFR amplification and no TP 53 mutation. In the other four cell cultures and D 384 cell line no genetic alterations were diagnosed. Histopathological classification of glioblastoma multiforme and/or genetic alterations resulted in lower radiosensitivity. Conclusion: In this small series of early passage glioma cell cultures low radiosensitivity and alterations in cell regulatory genes were seen. Further testing of biological behavior in larger series of patient-derived material is ongoing. (orig.)

  8. Penetrance of adrenocortical tumours associated with the germline TP53 R337H mutation.

    Science.gov (United States)

    Figueiredo, B C; Sandrini, R; Zambetti, G P; Pereira, R M; Cheng, C; Liu, W; Lacerda, L; Pianovski, M A; Michalkiewicz, E; Jenkins, J; Rodriguez-Galindo, C; Mastellaro, M J; Vianna, S; Watanabe, F; Sandrini, F; Arram, S B I; Boffetta, P; Ribeiro, R C

    2006-01-01

    An inherited germline P53 mutation has been identified in cases of childhood adrenocortical carcinoma (ACT), a neoplasm with a high incidence in southern Brazil. The penetrance of ACT in carriers of the point mutation, which encodes an arginine-to-histidine substitution at codon 337 of TP53 (R337H), has not been determined. To investigate the penetrance of childhood ACT in carriers of the R337H TP53 mutation. The family histories of 30 kindreds of 41 southern Brazilian children with ACT were obtained. A PCR based assay was used to detect this P53 mutation in a large number of relatives of children with ACT. In all, 927 individuals were tested for the mutation, 232 from the non-carrier and 695 (including the 40 probands) from the carrier parental lines. 40 children with ACT carried the TP53 R337H mutation; the remaining child with ACT was not tested. There was no evidence of Li-Fraumeni syndrome in any of the kindreds; however, seven met the criteria for Li-Fraumeni-like syndrome. The carrier parental line was identified in each kindred. Of the 695 individuals tested in the carrier parental line, 240 (34.5%) were positive for the mutation, while none of the 232 individuals in the other parental line carried the mutation. The penetrance of ACT was 9.9% (95% confidence interval, 8.7% to 11.1%). The TP53 R337H mutation dramatically increases predisposition to childhood ACT but not to other cancers, and explains the increased frequency of ACT observed in this geographic region.

  9. Diffuse large B-cell lymphoma with combined TP53 mutation and MIR34A methylation

    DEFF Research Database (Denmark)

    Asmar, Fazila; Hother, Christoffer; Kulosman, Gorjan

    2014-01-01

    MiR34A, B and C have been implicated in lymphomagenesis, but information on their role in normal CD19+ B-cells (PBL-B) and de novo diffuse large B-cell lymphoma (DLBCL) is limited. We show that in normal and activated B-cells miR34A-5p plays a dominant role compared to other miR34 family members....... Only miR34A-5p is expressed in PBL-B, and significantly induced in activated B-cells and reactive lymph nodes. In PBL-B, the MIR34A and MIR34B/C promoters are unmethylated, but the latter shows enrichment for the H3K4me3/H3K27me3 silencing mark. Nine de novo DLBCL cases (n=150) carry both TP53 mutation...... negative prognostic factor for survival (P=0.0002). In 2 DLBCL-cell lines with both TP53 mutation and promoter methylation of MIR34A, miR34A-5p is upregulated by 5-aza-2'deoxycytidine. Thus, the TP53/MIR34A "double hit" characterizes a very aggressive subgroup of DLBCL, which may be treatable...

  10. The TP53 tumour suppressor gene in colorectal carcinomas. I. Genetic alterations on chromosome 17.

    Science.gov (United States)

    Meling, G. I.; Lothe, R. A.; Børresen, A. L.; Graue, C.; Hauge, S.; Clausen, O. P.; Rognum, T. O.

    1993-01-01

    In 231 colorectal carcinomas, allele variation at four restriction fragments length polymorphisms (RFLP) loci on chromosome 17 have been studied by Southern analysis. Heterozygous loss of the TP53 gene was found in 68% (129/189) of the carcinomas informative on both chromosome arms. In 41% (77/189) of the carcinomas the loss was found only on 17p. Two probes were used to detect alterations on 17p, pBHP53 and pYNZ22. When loss was demonstrated with pYNZ22, pBHP53 also always showed loss (n = 45), whereas when loss was demonstrated with pBHP53, only 45 of 54 (83%) showed loss with pYNZ22. Loss on 17q was found in 34% (64/189) of the carcinomas, and 6% (12/189) had loss on this chromosome arm, only. Loss on 17q was significantly associated with loss on 17p (P < 0.01). These data confirm that the TP53 gene is the target of loss on chromosome arm 17p in colorectal carcinomas, and demonstrate that loss of the TP53 gene is most frequently part of limited, subchromosomal loss. Furthermore, the results do not suggest any additional tumour suppressor gene(s) on chromosome 17 involved in colorectal carcinogenesis. Images Figure 2 PMID:8094008

  11. Src kinases in chondrosarcoma chemoresistance and migration: dasatinib sensitises to doxorubicin in TP53 mutant cells

    Science.gov (United States)

    van Oosterwijk, J G; van Ruler, M A J H; Briaire-de Bruijn, I H; Herpers, B; Gelderblom, H; van de Water, B; Bovée, J V M G

    2013-01-01

    Background: Chondrosarcomas are malignant cartilage-forming tumours of bone. Because of their resistance to conventional chemotherapy and radiotherapy, currently no treatment strategies exist for unresectable and metastatic chondrosarcoma. Previously, PI3K/AKT/GSK3β and Src kinase pathways were shown to be activated in chondrosarcoma cell lines. Our aim was to investigate the role of these kinases in chemoresistance and migration in chondrosarcoma in relation to TP53 mutation status. Methods: We used five conventional and three dedifferentiated chondrosarcoma cell lines and investigated the effect of PI3K/AKT/GSK3β pathway inhibition (enzastaurin) and Src pathway inhibition (dasatinib) in chemoresistance using WST assay and live cell imaging with AnnexinV staining. Immunohistochemistry on tissue microarrays (TMAs) containing 157 cartilaginous tumours was performed for Src family members. Migration assays were performed with the RTCA xCelligence System. Results: Src inhibition was found to overcome chemoresistance, to induce apoptosis and to inhibit migration. Cell lines with TP53 mutations responded better to combination therapy than wild-type cell lines (P=0.002). Tissue microarray immunohistochemistry confirmed active Src (pSrc) signalling, with Fyn being most abundantly expressed (76.1%). Conclusion: These results strongly indicate Src family kinases, in particular Fyn, as a potential target for the treatment of inoperable and metastatic chondrosarcomas, and to sensitise for doxorubicin especially in the presence of TP53 mutations. PMID:23922104

  12. Molecular Characterization of TP53 Gene in Human Populations Exposed to Low-Dose Ionizing Radiation

    Directory of Open Access Journals (Sweden)

    Igor Brasil-Costa

    2013-01-01

    Full Text Available Ionizing radiation, such as that emitted by uranium, may cause mutations and consequently lead to neoplasia in human cells. The TP53 gene acts to maintain genomic integrity and constitutes an important biomarker of susceptibility. The present study investigated the main alterations observed in exons 4, 5, 6, 7, and 8 of the TP53 gene and adjacent introns in Amazonian populations exposed to radioactivity. Samples were collected from 163 individuals. Occurrence of the following alterations was observed: (i a missense exchange in exon 4 (Arg72Pro; (ii 2 synonymous exchanges, 1 in exon 5 (His179His, and another in exon 6 (Arg213Arg; (iii 4 intronic exchanges, 3 in intron 7 (C → T at position 13.436; C → T at position 13.491; T → G at position 13.511 and 1 in intron 8 (T → G at position 13.958. Alteration of codon 72 was found to be an important risk factor for cancer development (P=0.024; OR=6.48; CI: 1.29–32.64 when adjusted for age and smoking. Thus, TP53 gene may be an important biomarker for carcinogenesis susceptibility in human populations exposed to ionizing radiation.

  13. TP53 codon 72 polymorphism is associated with pancreatic cancer risk in males, smokers and drinkers.

    Science.gov (United States)

    Sonoyama, Takayuki; Sakai, Akiko; Mita, Yuichiro; Yasuda, Yukiko; Kawamoto, Hirofumi; Yagi, Takahito; Yoshioka, Masao; Mimura, Tetsushige; Nakachi, Kei; Ouchida, Mamoru; Yamamoto, Kazuhide; Shimizu, Kenji

    2011-01-01

    Tumor protein p53 (TP53) is the best-known tumor suppressor gene and plays a crucial role in carcinogenesis. The TP53 Arg 72 Pro polymorphism has been reported to be a risk factor for several types of cancer, but its association with pancreatic cancer has not been fully evaluated. Therefore, we investigated the effects of this polymorphism on pancreatic cancer in relation to smoking and drinking habits by examining the distribution of the SNP genotypes in 226 pancreatic cancer patients and 448 healthy controls. The frequencies of Arg/Arg, Arg/Pro and Pro/Pro were found to be 37, 49 and 15% in the pancreatic cancer cases and 44, 46 and 10% in the controls, respectively. Compared to the controls with the Arg/Arg genotype, cases with Pro/Pro homozygosity exhibited a significantly increased risk [adjusted odds ratio (OR)=1.70; 95% confidence interval (CI) 1.01-2.88]. In stratified studies, the association was particularly strong in males (OR=2.62; 95% CI 1.32-5.23), particularly in those smoking in excess of 20 pack-years and drinking in excess of 23 g ethanol/day (OR=5.02; 95% CI 1.12-22.51). We found that the TP53 Pro/Pro genotype compared to the Arg/Arg genotype had a profound effect on pancreatic cancer risk among males, particularly among heavy smokers and excessive alcohol drinkers.

  14. Genetic variation in the TP53 pathway and bladder cancer risk. a comprehensive analysis.

    Directory of Open Access Journals (Sweden)

    Silvia Pineda

    Full Text Available Germline variants in TP63 have been consistently associated with several tumors, including bladder cancer, indicating the importance of TP53 pathway in cancer genetic susceptibility. However, variants in other related genes, including TP53 rs1042522 (Arg72Pro, still present controversial results. We carried out an in depth assessment of associations between common germline variants in the TP53 pathway and bladder cancer risk.We investigated 184 tagSNPs from 18 genes in 1,058 cases and 1,138 controls from the Spanish Bladder Cancer/EPICURO Study. Cases were newly-diagnosed bladder cancer patients during 1998-2001. Hospital controls were age-gender, and area matched to cases. SNPs were genotyped in blood DNA using Illumina Golden Gate and TaqMan assays. Cases were subphenotyped according to stage/grade and tumor p53 expression. We applied classical tests to assess individual SNP associations and the Least Absolute Shrinkage and Selection Operator (LASSO-penalized logistic regression analysis to assess multiple SNPs simultaneously.Based on classical analyses, SNPs in BAK1 (1, IGF1R (5, P53AIP1 (1, PMAIP1 (2, SERINPB5 (3, TP63 (3, and TP73 (1 showed significant associations at p-value≤0.05. However, no evidence of association, either with overall risk or with specific disease subtypes, was observed after correction for multiple testing (p-value≥0.8. LASSO selected the SNP rs6567355 in SERPINB5 with 83% of reproducibility. This SNP provided an OR = 1.21, 95%CI 1.05-1.38, p-value = 0.006, and a corrected p-value = 0.5 when controlling for over-estimation.We found no strong evidence that common variants in the TP53 pathway are associated with bladder cancer susceptibility. Our study suggests that it is unlikely that TP53 Arg72Pro is implicated in the UCB in white Europeans. SERPINB5 and TP63 variation deserve further exploration in extended studies.

  15. The TP53 tumour suppressor gene in colorectal carcinomas. II. Relation to DNA ploidy pattern and clinicopathological variables.

    Science.gov (United States)

    Meling, G. I.; Lothe, R. A.; Børresen, A. L.; Graue, C.; Hauge, S.; Clausen, O. P.; Rognum, T. O.

    1993-01-01

    Heterozygous loss of the TP53 gene on chromosome arm 17p in colorectal carcinomas was strongly associated with DNA aneuploidy (P or = 1.1 and or = 1.3 had a significantly higher frequency of TP53 gene loss (85%) (P < 0.0001 and P < 0.0001, respectively). There was a significant association between loss of the TP53 gene and histological grade (P < 0.01), and there tended to be an association between loss of the TP53 gene and degree of cellular atypia (P < 0.05), with TP53 gene loss being most frequent in moderately differentiated carcinomas, and in carcinomas with severe cellular atypia, respectively. The proportion of tumours with loss of the TP53 gene increased significantly towards the distal part of the large bowel (P < 0.0001). These results indicate that different genetic mechanisms may be involved in the carcinogenesis in colon and rectum carcinomas, and in the two subsets of DNA aneuploid carcinomas. Furthermore, the data may suggest a role for the TP53 gene in the aneuploidisation process, possibly as a 'target' for a whole chromosome loss. PMID:8427784

  16. LncRNA-TP53TG1 Participated in the Stress Response Under Glucose Deprivation in Glioma.

    Science.gov (United States)

    Chen, Xin; Gao, Yang; Li, Deheng; Cao, Yiqun; Hao, Bin

    2017-12-01

    Gliomas are the most common brain tumors of the center nervous system. And long non-coding RNAs (lncRNAs) are non-protein coding transcripts, which have been considered as one type of gene expression regulator for cancer development. In this study, we investigated the role of lncRNA-TP53TG1 in response to glucose deprivation in human gliomas. The expression levels of TP53TG1 in glioma tissues and cells were analyzed by qRT-PCR. In addition, the influence of TP53TG1 on glucose metabolism related genes at the mRNA level during both high and low glucose treatment was detected by qRT-PCR. MTT, clonogenicity assays, and flow cytometry were performed to detect the cell proliferation and cell apoptosis. Furthermore, the migration of glioma cells was examined by Transwell assays. The expression of TP53TG1 was significantly higher in human glioma tissues or cell lines compared with normal brain tissue or NHA. Moreover, TP53TG1 and some tumor glucose metabolism related genes, such as GRP78, LDHA, and IDH1 were up-regulated significantly in U87 and LN18 cells under glucose deprivation. In addition, knockdown of TP53TG1 decreased cell proliferation and migration and down-regulated GRP78 and IDH1 expression levels and up-regulated PKM2 levels in U87 cells under glucose deprivation. However, over-expression of TP53TG1 showed the opposite tendency. Moreover, the effects of TP53TG1 were more remarkable in low glucose than that in high glucose. Our data showed that TP53TG1 under glucose deprivation may promote cell proliferation and migration by influencing the expression of glucose metabolism related genes in glioma. J. Cell. Biochem. 118: 4897-4904, 2017. © 2017 Wiley Periodicals, Inc. © 2017 Wiley Periodicals, Inc.

  17. TP53 mutation-mediated genomic instability induces the evolution of chemoresistance and recurrence in epithelial ovarian cancer.

    Science.gov (United States)

    Zhang, Meiying; Zhuang, Guanglei; Sun, Xiangjun; Shen, Yanying; Wang, Wenjing; Li, Qing; Di, Wen

    2017-02-02

    Genomic instability caused by mutation of the checkpoint molecule TP53 may endow cancer cells with the ability to undergo genomic evolution to survive stress and treatment. We attempted to gain insight into the potential contribution of ovarian cancer genomic instability resulted from TP53 mutation to the aberrant expression of multidrug resistance gene MDR1. TP53 mutation status was assessed by performing nucleotide sequencing and immunohistochemistry. Ovarian cancer cell DNA ploidy was determined using Feulgen-stained smears or flow cytometry. DNA copy number was analyzed by performing fluorescence in situ hybridization (FISH). In addition to performing nucleotide sequencing for 5 cases of ovarian cancer, TP53 mutations were analyzed via immunohistochemical staining for P53. Both intensive P53 immunohistochemical staining and complete absence of signal were associated with the occurrence of TP53 mutations. HE staining and the quantification of DNA content indicated a significantly higher proportion of polyploidy and aneuploidy cells in the TP53 mutant group than in the wild-type group (p ovarian cancer patients, multivariate logistic analysis identified late FIGO (International Federation of Gynecology and Obstetrics) stage, serous histotype, G3 grade and TP53 mutation as independent risk factors for ovarian cancer recurrence. In relapse patients, the proportion of chemoresistant cases in the TP53 wild-type group was significantly lower than in the mutant group (63.6% vs. 91.8%, p 6 MDR1 copies and chromosome 7 amplication in the TP53 mutant group than in the wild-type group [11.7 ± 2.3% vs. 3.0 ± 0.7% and 2.1 ± 0.7% vs. 0.3 ± 0.05%, (p ovarian cancer chemoresistance and recurrence. Our findings lay the foundation for the development of promising chemotherapeutic approaches to treat aggressive and recurrent ovarian cancer.

  18. Fischer-344 Tp53-knockout rats exhibit a high rate of bone and brain neoplasia with frequent metastasis

    Directory of Open Access Journals (Sweden)

    Sarah A. Hansen

    2016-10-01

    Full Text Available Somatic mutations in the Tp53 tumor suppressor gene are the most commonly seen genetic alterations in cancer, and germline mutations in Tp53 predispose individuals to a variety of early-onset cancers. Development of appropriate translational animal models that carry mutations in Tp53 and recapitulate human disease are important for drug discovery, biomarker development and disease modeling. Current Tp53 mouse and rat models have significant phenotypic and genetic limitations, and often do not recapitulate certain aspects of human disease. We used a marker-assisted speed congenic approach to transfer a well-characterized Tp53-mutant allele from an outbred rat to the genetically inbred Fischer-344 (F344 rat to create the F344-Tp53tm1(EGFP-PacQly/Rrrc (F344-Tp53 strain. On the F344 genetic background, the tumor spectrum shifted, with the primary tumor types being osteosarcomas and meningeal sarcomas, compared to the hepatic hemangiosarcoma and lymphoma identified in the original outbred stock model. The Fischer model is more consistent with the early onset of bone and central nervous system sarcomas found in humans with germline Tp53 mutations. The frequency of osteosarcomas in F344-Tp53 homozygous and heterozygous animals was 57% and 36%, respectively. Tumors were highly representative of human disease radiographically and histologically, with tumors found primarily on long bones with frequent pulmonary metastases. Importantly, the rapid onset of osteosarcomas in this promising new model fills a current void in animal models that recapitulate human pediatric osteosarcomas and could facilitate studies to identify therapeutic targets.

  19. Mutations in BRCA1, BRCA2 and other breast and ovarian cancer susceptibility genes in Central and South American populations.

    Science.gov (United States)

    Jara, Lilian; Morales, Sebastian; de Mayo, Tomas; Gonzalez-Hormazabal, Patricio; Carrasco, Valentina; Godoy, Raul

    2017-10-06

    Breast cancer (BC) is the most common malignancy among women worldwide. A major advance in the understanding of the genetic etiology of BC was the discovery of BRCA1 and BRCA2 (BRCA1/2) genes, which are considered high-penetrance BC genes. In non-carriers of BRCA1/2 mutations, disease susceptibility may be explained of a small number of mutations in BRCA1/2 and a much higher proportion of mutations in ethnicity-specific moderate- and/or low-penetrance genes. In Central and South American populations, studied have focused on analyzing the distribution and prevalence of BRCA1/2 mutations and other susceptibility genes that are scarce in Latin America as compared to North America, Europe, Australia, and Israel. Thus, the aim of this review is to present the current state of knowledge regarding pathogenic BRCA variants and other BC susceptibility genes. We conducted a comprehensive review of 47 studies from 12 countries in Central and South America published between 2002 and 2017 reporting the prevalence and/or spectrum of mutations and pathogenic variants in BRCA1/2 and other BC susceptibility genes. The studies on BRCA1/2 mutations screened a total of 5956 individuals, and studies on susceptibility genes analyzed a combined sample size of 11,578 individuals. To date, a total of 190 different BRCA1/2 pathogenic mutations in Central and South American populations have been reported in the literature. Pathogenic mutations or variants that increase BC risk have been reported in the following genes or genomic regions: ATM, BARD1, CHECK2, FGFR2, GSTM1, MAP3K1, MTHFR, PALB2, RAD51, TOX3, TP53, XRCC1, and 2q35.

  20. Study of the TP53 codon 72 polymorphism in oral cancer and oral potentially malignant disorders in Argentine patients.

    Science.gov (United States)

    Zarate, Ana Maria; Don, Julieta; Secchi, Dante; Carrica, Andres; Galindez Costa, Fernanda; Panico, Rene; Brusa, Martin; Barra, José Luis; Brunotto, Mabel

    2017-05-01

    The aim of this work was to evaluate the prevalence of TP53Arg72Pro mutations and their possible relationship with oral carcinoma and oral potentially malignant disorders in Argentine patients. A cross-sectional study was performed on 111 exfoliated cytologies from patients with oral cancer (OC), oral potentially malignant disorders (OPMD) and controls. The TP53Arg72Pro mutations were determined using conventional PCR. We evaluated univariate and multivariate study variables, setting p oral leukoplakia (OL) diagnosis; (b) multivariate association among the TP53CC genotype and females over 45 years with no tobacco nor alcohol habits with oral lichen planus pathology; (c) multivariate association between the TP53GC genotype and males with alcohol and tobacco habits and OC and OL pathologies. Our results showed that the wild-type Arg72variant was related to control patients and Pro72variant was related to OC and OPMD, in Argentine patients.

  1. A functionally significant SNP in TP53 and breast cancer risk in African-American women.

    Science.gov (United States)

    Murphy, Maureen E; Liu, Song; Yao, Song; Huo, Dezheng; Liu, Qin; Dolfi, Sonia C; Hirshfield, Kim M; Hong, Chi-Chen; Hu, Qiang; Olshan, Andrew F; Ogundiran, Temidayo O; Adebamowo, Clement; Domchek, Susan M; Nathanson, Katherine L; Nemesure, Barbara; Ambs, Stefan; Blot, William J; Feng, Ye; John, Esther M; Bernstein, Leslie; Zheng, Wei; Hu, Jennifer J; Ziegler, Regina G; Nyante, Sarah; Ingles, Sue A; Press, Michael F; Deming, Sandra L; Rodriguez-Gil, Jorge L; Haiman, Christopher A; Olopade, Olufunmilayo I; Lunetta, Kathryn L; Palmer, Julie R; Ambrosone, Christine B

    2017-01-01

    A coding region polymorphism exists in the TP53 gene (Pro47Ser; rs1800371) in individuals of African descent, which reduces p53 tumor suppressor function in a mouse model. It has been unclear whether this functionally significant polymorphism alters cancer risk in humans. This analysis included 6907 women with breast cancer and 7644 controls from the AMBER, ROOT, and AABC consortia. We used multivariable logistic regression to estimate associations between the TP53 Pro47Ser allele and overall breast cancer risk. Because polymorphisms in TP53 tend to be associated with cancer risk in pre-menopausal women, we also limited our analyses to this population in the AMBER and ROOT consortia, where menopausal status was known, and conducted a fixed effects meta-analysis. In an analysis of all women in the AMBER, ROOT, and AABC consortia, we found no evidence for association of the Pro47Ser variant with breast cancer risk. However, when we restricted our analysis to only pre-menopausal women from the AMBER and ROOT consortia, there was a per allele odds ratio of 1.72 (95% confidence interval 1.08-2.76; p-value = 0.023). Although the Pro47Ser variant was not associated with overall breast cancer risk, it may increase risk among pre-menopausal women of African ancestry. Following up on more studies in human populations may better elucidate the role of this variant in breast cancer etiology. However, because of the low frequency of the polymorphism in women of African ancestry, its impact at a population level may be minimal.

  2. Analysis of full coding sequence of the TP53 gene in invasive vulvar cancers: Implications for therapy.

    Science.gov (United States)

    Kashofer, Karl; Regauer, Sigrid

    2017-08-01

    This study evaluates the frequency and type of TP53 gene mutations and HPV status in 72 consecutively diagnosed primary invasive vulvar squamous cell carcinomas (SCC) during the past 5years. DNA of formalin-fixed and paraffin embedded tumour tissue was analysed for 32 HPV subtypes and the full coding sequence of the TP53 gene, and correlated with results of p53 immunohistochemistry. 13/72 (18%) cancers were HPV-induced squamous cell carcinomas, of which 1/13 (8%) carcinoma harboured a somatic TP53 mutation. Among the 59/72 (82%) HPV-negative cancers, 59/72 (82%) SCC were HPV-negative with wild-type gene in 14/59 (24%) SCC and somatic TP53 mutations in 45/59 (76%) SCC. 28/45 (62%) SCC carried one (n=20) or two (n=8) missense mutations. 11/45 (24%) carcinomas showed a single disruptive mutation (3× frame shift, 7× stop codon, 1× deletion), 3/45 SCC a splice site mutation. 3/45 (7%) carcinomas had 2 or 3 different mutations. 18 different "hot spot" mutations were observed in 22/45 cancers (49%; 5× R273, 3× R282; 2× each Y220, R278, R248). Immunohistochemical p53 over expression was identified in most SCC with missense mutations, but not in SCC with disruptive TP53 mutations or TP53 wild-type. 14/45 (31%) patients with TP53 mutated SCC died of disease within 12months (range 2-24months) versus 0/13 patients with HPV-induced carcinomas and 0/14 patients with HPV-negative, TP53 wild-type carcinomas. 80% of primary invasive vulvar SCC were HPV-negative carcinomas with a high frequency of disruptive mutations and "hot spot" TP53 gene mutations, which have been linked to chemo- and radioresistance. The death rate of patients with p53 mutated vulvar cancers was 31%. Immunohistochemical p53 over expression could not reliably identify SCC with TP53 gene mutation. Pharmacological therapies targeting mutant p53 will be promising strategies for personalized therapy in patients with TP53 mutated vulvar cancers. Copyright © 2017. Published by Elsevier Inc.

  3. Rare copy number variants observed in hereditary breast cancer cases disrupt genes in estrogen signaling and TP53 tumor suppression network.

    Directory of Open Access Journals (Sweden)

    Katri Pylkäs

    Full Text Available Breast cancer is the most common cancer in women in developed countries, and the contribution of genetic susceptibility to breast cancer development has been well-recognized. However, a great proportion of these hereditary predisposing factors still remain unidentified. To examine the contribution of rare copy number variants (CNVs in breast cancer predisposition, high-resolution genome-wide scans were performed on genomic DNA of 103 BRCA1, BRCA2, and PALB2 mutation negative familial breast cancer cases and 128 geographically matched healthy female controls; for replication an independent cohort of 75 similarly mutation negative young breast cancer patients was used. All observed rare variants were confirmed by independent methods. The studied breast cancer cases showed a consistent increase in the frequency of rare CNVs when compared to controls. Furthermore, the biological networks of the disrupted genes differed between the two groups. In familial cases the observed mutations disrupted genes, which were significantly overrepresented in cellular functions related to maintenance of genomic integrity, including DNA double-strand break repair (P = 0.0211. Biological network analysis in the two independent breast cancer cohorts showed that the disrupted genes were closely related to estrogen signaling and TP53 centered tumor suppressor network. These results suggest that rare CNVs represent an alternative source of genetic variation influencing hereditary risk for breast cancer.

  4. Rare copy number variants observed in hereditary breast cancer cases disrupt genes in estrogen signaling and TP53 tumor suppression network.

    Science.gov (United States)

    Pylkäs, Katri; Vuorela, Mikko; Otsukka, Meeri; Kallioniemi, Anne; Jukkola-Vuorinen, Arja; Winqvist, Robert

    2012-01-01

    Breast cancer is the most common cancer in women in developed countries, and the contribution of genetic susceptibility to breast cancer development has been well-recognized. However, a great proportion of these hereditary predisposing factors still remain unidentified. To examine the contribution of rare copy number variants (CNVs) in breast cancer predisposition, high-resolution genome-wide scans were performed on genomic DNA of 103 BRCA1, BRCA2, and PALB2 mutation negative familial breast cancer cases and 128 geographically matched healthy female controls; for replication an independent cohort of 75 similarly mutation negative young breast cancer patients was used. All observed rare variants were confirmed by independent methods. The studied breast cancer cases showed a consistent increase in the frequency of rare CNVs when compared to controls. Furthermore, the biological networks of the disrupted genes differed between the two groups. In familial cases the observed mutations disrupted genes, which were significantly overrepresented in cellular functions related to maintenance of genomic integrity, including DNA double-strand break repair (P = 0.0211). Biological network analysis in the two independent breast cancer cohorts showed that the disrupted genes were closely related to estrogen signaling and TP53 centered tumor suppressor network. These results suggest that rare CNVs represent an alternative source of genetic variation influencing hereditary risk for breast cancer.

  5. Common variants in the ATM, BRCA1, BRCA2, CHEK2 & TP53 cancer susceptibility genes are unlikely to increase breast cancer risk

    OpenAIRE

    Baynes, Caroline; Healey, Catherine S.; Pooley, Karen Anne; Scollen, Serena A; Luben, Robert; Thompson, Deborah Jane; Pharoah, Paul David; Easton, Douglas Frederick; Ponder, Bruce Anthony; Dunning, Alison Margaret

    2007-01-01

    RIGHTS : This article is licensed under the BioMed Central licence at http://www.biomedcentral.com/about/license which is similar to the 'Creative Commons Attribution Licence'. In brief you may : copy, distribute, and display the work; make derivative works; or make commercial use of the work - under the following conditions: the original author must be given credit; for any reuse or distribution, it must be made clear to others what the license terms of this work are.

  6. Clinical Impact of TP53 Gene Mutations in Diffuse Large B-Cell Lymphoma (DLBCL)

    DEFF Research Database (Denmark)

    Young, Ken H; Patten, Nancy; Truong, Sim

    2009-01-01

    Mutations of the TP53 tumor suppressor gene are associated with a poor clinical outcome in DLBCL patients treated with CHOP. The impact of TP53 mutations on clinical outcome of DLBCL patients treated with Rituxan-CHOP has not been comprehensively analyzed. The purpose of this study was to analyze...... or Rituxan-CHOP regimen. These findings also provide the rationale and strategies for p53 targeted therapeutic intervention in DLBCL patients. Disclosures: Kahl: Milllennium: Consultancy, Research Funding; Cephalon: Consultancy, Research Funding....

  7. Clinicopathological features and clinical outcomes associated with TP53 and BRAFNon-V600 mutations in cutaneous melanoma patients.

    Science.gov (United States)

    Kim, Dae Won; Haydu, Lauren E; Joon, Aron Y; Bassett, Roland L; Siroy, Alan E; Tetzlaff, Michael T; Routbort, Mark J; Amaria, Rodabe N; Wargo, Jennifer A; McQuade, Jennifer L; Kemnade, Jan; Hwu, Patrick; Woodman, Scott E; Roszik, Jason; Kim, Kevin B; Gershenwald, Jeffrey E; Lazar, Alexander J; Davies, Michael A

    2017-04-15

    BRAFV600 , NRAS, TP53, and BRAFNon-V600 are among the most common mutations detected in non-acral cutaneous melanoma patients. Although several studies have identified clinical and pathological features associated with BRAFV600 and NRAS mutations, limited data are available regarding the correlates and significance of TP53 and BRAFNon-V600 mutations. This study analyzed the patient demographics, primary tumor features, and clinical outcomes of a large cohort of non-acral cutaneous melanoma patients who had undergone clinically indicated molecular testing (n = 926). The prevalence of BRAFV600 , NRAS, TP53, and BRAFNon-V600 mutations was 43%, 21%, 19%, and 7%, respectively. The presence of a TP53 mutation was associated with older age (P = .019), a head and neck primary tumor site (P = .0001), and longer overall survival (OS) from the diagnosis of stage IV disease in univariate (P = .039) and multivariate analyses (P = .015). BRAFNon-V600 mutations were associated with older age (P = .005) but not with primary tumor features or OS from stage IV. Neither TP53 nor BRAFNon-V600 mutations correlated significantly with OS with frontline ipilimumab treatment, and the TP53 status was not significantly associated with outcomes with frontline BRAF inhibitor therapy. Eleven patients with BRAFNon-V600 mutations were treated with a BRAF inhibitor. Three patients were not evaluable for a response because of treatment cessation for toxicities; the remaining patients had disease progression as the best response to therapy. These results add to the understanding of the clinical features associated with TP53 and BRAFNon-V600 mutations in advanced cutaneous melanoma patients, and they support the rationale for evaluating the prognostic significance of TP53 in other cohorts of melanoma patients. Cancer 2017;123:1372-1381. © 2016 American Cancer Society. © 2016 American Cancer Society.

  8. TP53-dependent chromosome instability is associated with transient reductions in telomere length in immortal telomerase-positive cell lines

    Science.gov (United States)

    Schwartz, J. L.; Jordan, R.; Liber, H.; Murnane, J. P.; Evans, H. H.

    2001-01-01

    Telomere shortening in telomerase-negative somatic cells leads to the activation of the TP53 protein and the elimination of potentially unstable cells. We examined the effect of TP53 gene expression on both telomere metabolism and chromosome stability in immortal, telomerase-positive cell lines. Telomere length, telomerase activity, and chromosome instability were measured in multiple clones isolated from three related human B-lymphoblast cell lines that vary in TP53 expression; TK6 cells express wild-type TP53, WTK1 cells overexpress a mutant form of TP53, and NH32 cells express no TP53 protein. Clonal variations in both telomere length and chromosome stability were observed, and shorter telomeres were associated with higher levels of chromosome instability. The shortest telomeres were found in WTK1- and NH32-derived cells, and these cells had 5- to 10-fold higher levels of chromosome instability. The primary marker of instability was the presence of dicentric chromosomes. Aneuploidy and other stable chromosome alterations were also found in clones showing high levels of dicentrics. Polyploidy was found only in WTK1-derived cells. Both telomere length and chromosome instability fluctuated in the different cell populations with time in culture, presumably as unstable cells and cells with short telomeres were eliminated from the growing population. Our results suggest that transient reductions in telomere lengths may be common in immortal cell lines and that these alterations in telomere metabolism can have a profound effect on chromosome stability. Copyright 2000 Wiley-Liss, Inc.

  9. Constitutional mosaicism of a de novo TP53 mutation in a patient with bilateral choroid plexus carcinoma.

    Science.gov (United States)

    Trubicka, Joanna; Filipek, Iwona; Piotr, Iwanowski; Rydzanicz, Małgorzata; Grajkowska, Wiesława; Piekutowska-Abramczuk, Dorota; Chrzanowska, Krystyna; Karkucińska-Więckowska, Agnieszka; Iwanicka-Pronicka, Katarzyna; Pronicki, Maciej; Łastowska, Maria; Płoski, Rafał; Dembowska-Bagińska, Bożenna

    2017-10-01

    Choroid plexus tumors (CPT) constitute 2%-5% of all pediatric brain tumors and include high grade choroid plexus carcinoma (CPC). About 40% of CPC patients harbor germline TP53 mutations, associated with diminished survival rates. However, the number of TP53 carriers might be underestimated due to suboptimal ability of Sanger sequencing to identify mosaicism. We describe an 18-month-old boy with ultra-rare, bilateral disseminated CPC and negative family history of cancer. Next generation sequencing (NGS) revealed constitutional mosaicism of de novo TP53 mutation, which was barely detectable by Sanger sequencing. This is the first description of a de novo TP53 mutation mosaicism in a patient with CPC. Up to now four cases of de novo TP53 mutations in CPC patients have been described but none of them were mosaic. Since TP53 mutation mosaicism may have an impact on management of patients and predisposition to other cancers, a reliable method of identification is important. Our results highlight the utility of high-throughput technologies in detection of potentially important genetic markers. Copyright © 2017 Elsevier Inc. All rights reserved.

  10. Ubc9 mediates nuclear localization and growth suppression of BRCA1 and BRCA1a proteins.

    Science.gov (United States)

    Qin, Yunlong; Xu, Jingyao; Aysola, Kartik; Begum, Nurjahan; Reddy, Vaishali; Chai, Yuli; Grizzle, William E; Partridge, Edward E; Reddy, E Shyam P; Rao, Veena N

    2011-12-01

    BRCA1 gene mutations are responsible for hereditary breast and ovarian cancers. In sporadic breast tumors, BRCA1 dysfunction or aberrant subcellular localization is thought to be common. BRCA1 is a nuclear-cytoplasm shuttling protein and the reason for cytoplasmic localization of BRCA1 in young breast cancer patients is not yet known. We have previously reported BRCA1 proteins unlike K109R and cancer-predisposing mutant C61G to bind Ubc9 and modulate ER-α turnover. In the present study, we have examined the consequences of altered Ubc9 binding and knockdown on the subcellular localization and growth inhibitory function of BRCA1 proteins. Our results using live imaging of YFP, GFP, RFP-tagged BRCA1, BRCA1a and BRCA1b proteins show enhanced cytoplasmic localization of K109 R and C61G mutant BRCA1 proteins in normal and cancer cells. Furthermore, down-regulation of Ubc9 in MCF-7 cells using Ubc9 siRNA resulted in enhanced cytoplasmic localization of BRCA1 protein and exclusive cytoplasmic retention of BRCA1a and BRCA1b proteins. These mutant BRCA1 proteins were transforming and impaired in their capacity to inhibit growth of MCF-7 and CAL51 breast cancer cells. Interestingly, cytoplasmic BRCA1a mutants showed more clonogenicity in soft agar and higher levels of expression of Ubc9 than parental MCF7 cells. This is the first report demonstrating the physiological link between cytoplasmic mislocalization of mutant BRCA1 proteins, loss of ER-α repression, loss of ubiquitin ligase activity and loss of growth suppression of BRCA1 proteins. Thus, binding of BRCA1 proteins to nuclear chaperone Ubc9 provides a novel mechanism for nuclear import and control of tumor growth. Copyright © 2011 Wiley-Liss, Inc.

  11. Breast cancer genes: beyond BRCA1 and BRCA2.

    Science.gov (United States)

    Filippini, Sandra E; Vega, Ana

    2013-06-01

    Breast cancer (BC) is a heterogeneous disease. The majority of breast cancer cases (about 70 percent) are considered sporadic. Familial breast cancer (about 30 percent of patients), often seen in families with a high incidence of BC, has been associated with a number of high-, moderate-, and low-penetrance susceptibility genes. Family linkage studies have identified high-penetrance genes, BRCA1, BRCA2, PTEN and TP53, that are responsible for inherited syndromes. Moreover, a combination of family-based and population-based approaches indicated that genes involved in DNA repair, such as CHEK2, ATM, BRIP1 (FANCJ), PALB2 (FANCN) and RAD51C (FANCO), are associated with moderate BC risk. Genome wide association studies (GWAS) in BC revealed a number of common low penetrance alleles associated with a slightly increased or decreased risk of BC. Currently, only high penetrance genes are used in clinical practice on a wide scale. Due to the development of next generation sequencing technologies, it is envisaged that all familial breast cancer genes will be included in the genetic test. However, additional research in clinical management of moderate and low-risk variants is needed before full implementation of multi-gene panel testing into clinical work-flows. In this review, we focus on the different components of familial breast cancer risk.

  12. Hepatitis B and Hepatitis C Infection Biomarkers and TP53 Mutations in Hepatocellular Carcinomas from Colombia

    Directory of Open Access Journals (Sweden)

    Maria-Cristina Navas

    2011-01-01

    Full Text Available Hepatocellular Carcinoma (HCC is a leading cause of cancer-related death worldwide. Globally, the most important HCC risk factors are Hepatitis B Virus (HBV and/or Hepatitis C Virus (HCV, chronic alcoholism, and dietary exposure to aflatoxins. We have described the epidemiological pattern of 202 HCC samples obtained from Colombian patients. Additionally we investigated HBV/HCV infections and TP53 mutations in 49 of these HCC cases. HBV biomarkers were detected in 58.1% of the cases; HBV genotypes F and D were characterized in three of the samples. The HCV biomarker was detected in 37% of the samples while HBV/HCV coinfection was found in 19.2%. Among TP53 mutations, 10.5% occur at the common aflatoxin mutation hotspot, codon 249. No data regarding chronic alcoholism was available from the cases. In conclusion, in this first study of HCC and biomarkers in a Colombian population, the main HCC risk factor was HBV infection.

  13. Initiation of prostate cancer in mice by Tp53R270H: evidence for an alternative molecular progression

    Directory of Open Access Journals (Sweden)

    Ruth L. Vinall

    2012-11-01

    Tp53 mutations are common in human prostate cancer (CaP, occurring with a frequency of ∼30% and ∼70% in localized and metastatic disease, respectively. In vitro studies have determined several common mutations of Tp53 that have specific gain-of-function properties in addition to loss of function, including the ability to promote castration-resistant (CR growth of CaP cells in some contexts. To date, a lack of suitable mouse models has prohibited investigation of the role played by Tp53 mutations in mediating CaP progression in vivo. Here, we describe the effects of conditional expression of a mutant Tp53 (Tp53R270H; equivalent to the human hotspot mutant R273H in the prostate epithelium of mice. Heterozygous “Tp53LSL-R270H/+” [129S4(Trp53tm3Tyj] and “Nkx3.1-Cre” [129S(Nkx3-1tm3(creMms] mice with prostate-specific expression of the Tp53R270H mutation (p53R270H/+ Nkx3.1-Cre mice were bred onto an FVB/N background via speed congenesis to produce strain FVB.129S4(Trp53tm3Tyj/wt; FVB.129S(Nkx3-1tm3(creMms/wt and littermate genotype negative control mice. These mutant mice had significantly increased incidences of prostatic intraepithelial neoplasia (PIN lesions, and these appeared earlier, compared with the Nkx3.1 haploinsufficient (Nkx3.1-Cre het littermate mice, which did not express the Tp53 mutation. PIN lesions in these mice showed consistent progression and some developed into invasive adenocarcinoma with a high grade, sarcomatoid or epithelial-mesenchymal transition (EMT phenotype. PIN lesions were similar to those seen in PTEN conditional knockout mice, with evidence of AKT activation concomitant with neoplastic proliferation. However, the invasive tumor phenotype is rarely seen in previously described mouse models of prostatic neoplasia. These data indicate that the Tp53R270H mutation plays a role in CaP initiation. This finding has not previously been reported. Further characterization of this model, particularly in a setting of androgen

  14. Overexpression of RBBP6, alone or combined with mutant TP53, is predictive of poor prognosis in colon cancer.

    Directory of Open Access Journals (Sweden)

    Jian Chen

    Full Text Available Retinoblastoma binding protein 6 (RBBP6 plays an important role in chaperone-mediated ubiquitination and interacts with TP53 in carcinogenesis. However, the clinicopathologic significance of RBBP6 expression in colon cancer is unknown; in particular, the prognostic value of RBBP6 combined with TP53 expression has not been explored. Therefore, quantitative real-time PCR and western blot analyses were performed to detect RBBP6 expression in colon cancer tissues. RBBP6 and TP53 expression were assessed by immunohistochemistry in a tissue microarray format, in which the primary colon cancer tissue was paired with noncancerous tissue. Tissue specimens were obtained from 203 patients. We found that RBBP6 was overexpressed in colon tumorous tissues and was significantly associated with clinical stage, depth of tumor invasion, lymph node metastasis (LNM, distant metastasis, and histologic grade. Further studies revealed that a corresponding correlation between RBBP6 overexpression and mutant TP53 was evident in colon cancer (r = 0.450; P<0.001. RBBP6 expression was an independent prognostic factor for overall survival (OS and disease free survival (DFS. Interestingly, patients with tumors that had both RBBP6 overexpression and mutant TP53 protein accumulation relapsed and died within a significantly short period after surgery (P<0.001. Multivariate analysis showed that patients with LNM and patients with both RBBP6- and TP53-positive tumors had extremely poor OS (HR 6.75; 95% CI 2.63-17.35; P<0.001 and DFS (HR 8.08; 95% CI 2.80-23.30; P<0.001. These clinical findings indicate that the assessment of both RBBP6 and mutant TP53 expression will be helpful in predicting colon cancer prognosis.

  15. A novel TP53 germline inframe deletion identified in a Spanish series of Li-fraumeni syndrome suspected families.

    Science.gov (United States)

    Llovet, Patricia; Illana, Francisco J; Martín-Morales, Lorena; de la Hoya, Miguel; Garre, Pilar; Ibañez-Royo, M Dolores; Pérez-Segura, Pedro; Caldés, Trinidad; García-Barberán, Vanesa

    2017-10-01

    Li-Fraumeni syndrome (LFS) is an autosomal dominant, inherited tumor predisposition syndrome associated with heterozygous germline mutations in the TP53 gene. The molecular diagnosis of LFS is important to develop strategies for early detection and access to the genetic counseling. Our study evaluated germline TP53 mutations in Spanish families with a history suggestive of LFS. Germline TP53 alterations in 22 families with a history suggestive of LFS were evaluated by Sanger sequencing and multiplex ligation-dependent probe amplification. Loss of heterozygosity analysis and immunohistochemistry of the protein in the tumor were performed in order to evaluate the pathogenicity of a novel alteration detected. A total of seven TP53 mutations were detected, six point mutations (4 missense and 2 nonsense) and a novel inframe deletion. 93% of mutation carriers developed at least one malignancy (mainly breast cancer and sarcomas), with a mean age at diagnosis of the first tumor of 30.2 years. Two missense mutations acted as dominant-negative. The novel inframe mutation c.437_445del was located in the DNA-binding domain. This mutation segregated with cancer in the family, and both high expression of the protein and loss of the wild-type TP53 allele were detected in the tumor of the carrier. We have found a novel inframe deletion in TP53 that likely results in the loss of p53 function and acts in a non-dominant negative way, although further studies are necessary to clarify this issue. The identification of novel TP53 alterations is crucial for a personalized cancer-risk management of the Li-Fraumeni syndrome.

  16. Germline TP53 Mutations in Patients With Early-Onset Colorectal Cancer in the Colon Cancer Family Registry.

    Science.gov (United States)

    Yurgelun, Matthew B; Masciari, Serena; Joshi, Victoria A; Mercado, Rowena C; Lindor, Noralane M; Gallinger, Steven; Hopper, John L; Jenkins, Mark A; Buchanan, Daniel D; Newcomb, Polly A; Potter, John D; Haile, Robert W; Kucherlapati, Raju; Syngal, Sapna

    2015-05-01

    Li-Fraumeni syndrome, usually characterized by germline TP53 mutations, is associated with markedly elevated lifetime risks of multiple cancers, and has been linked to an increased risk of early-onset colorectal cancer. To examine the frequency of germline TP53 alterations in patients with early-onset colorectal cancer. This was a multicenter cross-sectional cohort study of individuals recruited to the Colon Cancer Family Registry (CCFR) from 1998 through 2007 (genetic testing data updated as of January 2015). Both population-based and clinic-based patients in the United States, Canada, Australia, and New Zealand were recruited to the CCFR. Demographic information, clinical history, and family history data were obtained at enrollment. Biospecimens were collected from consenting probands and families, including microsatellite instability and DNA mismatch repair immunohistochemistry results. A total of a 510 individuals diagnosed as having colorectal cancer at age 40 years or younger and lacking a known hereditary cancer syndrome were identified from the CCFR as being potentially eligible. Fifty-three participants were excluded owing to subsequent identification of germline mutations in DNA mismatch repair genes (n = 47) or biallelic MUTYH mutations (n = 6). Germline sequencing of the TP53 gene was performed. Identified TP53 alterations were assessed for pathogenicity using literature and international mutation database searches and in silico prediction models. Frequency of nonsynonymous germline TP53 alterations. Among 457 eligible participants (314, population-based; 143, clinic-based; median age at diagnosis, 36 years [range, 15-40 years]), 6 (1.3%; 95% CI, 0.5%-2.8%) carried germline missense TP53 alterations, none of whom met clinical criteria for Li-Fraumeni syndrome. Four of the identified TP53 alterations have been previously described in the literature in probands with clinical features of Li-Fraumeni syndrome, and 2 were novel alterations. In a

  17. Remote intracranial recurrence of IDH mutant gliomas is associated with TP53 mutations and an 8q gain

    Science.gov (United States)

    Nakae, Shunsuke; Kato, Takema; Murayama, Kazuhiro; Sasaki, Hikaru; Abe, Masato; Kumon, Masanobu; Kumai, Tadashi; Yamashiro, Kei; Inamasu, Joji; Hasegawa, Mitsuhiro; Kurahashi, Hiroki; Hirose, Yuichi

    2017-01-01

    Most IDH mutant gliomas harbor either 1p/19q co-deletions or TP53 mutation; 1p/19q co-deleted tumors have significantly better prognoses than tumors harboring TP53 mutations. To investigate the clinical factors that contribute to differences in tumor progression of IDH mutant gliomas, we classified recurrent tumor patterns based on MRI and correlated these patterns with their genomic characterization. Accordingly, in IDH mutant gliomas (N = 66), 1p/19 co-deleted gliomas only recurred locally, whereas TP53 mutant gliomas recurred both locally and in remote intracranial regions. In addition, diffuse tensor imaging suggested that remote intracranial recurrence in the astrocytomas, IDH-mutant with TP53 mutations may occur along major fiber bundles. Remotely recurrent tumors resulted in a higher mortality and significantly harbored an 8q gain; astrocytomas with an 8q gain resulted in significantly shorter overall survival than those without an 8q gain. OncoScan® arrays and next-generation sequencing revealed specific 8q regions (i.e., between 8q22 and 8q24) show a high copy number. In conclusion, only tumors with TP53 mutations showed patterns of remote recurrence in IDH mutant gliomas. Furthermore, an 8q gain was significantly associated with remote intracranial recurrence and can be considered a poor prognostic factor in astrocytomas, IDH-mutant. PMID:29156679

  18. Remote intracranial recurrence ofIDHmutant gliomas is associated withTP53mutations and an 8q gain.

    Science.gov (United States)

    Nakae, Shunsuke; Kato, Takema; Murayama, Kazuhiro; Sasaki, Hikaru; Abe, Masato; Kumon, Masanobu; Kumai, Tadashi; Yamashiro, Kei; Inamasu, Joji; Hasegawa, Mitsuhiro; Kurahashi, Hiroki; Hirose, Yuichi

    2017-10-17

    Most IDH mutant gliomas harbor either 1p/19q co-deletions or TP53 mutation; 1p/19q co-deleted tumors have significantly better prognoses than tumors harboring TP53 mutations. To investigate the clinical factors that contribute to differences in tumor progression of IDH mutant gliomas, we classified recurrent tumor patterns based on MRI and correlated these patterns with their genomic characterization. Accordingly, in IDH mutant gliomas ( N = 66), 1p/19 co-deleted gliomas only recurred locally, whereas TP53 mutant gliomas recurred both locally and in remote intracranial regions. In addition, diffuse tensor imaging suggested that remote intracranial recurrence in the astrocytomas, IDH-mutant with TP53 mutations may occur along major fiber bundles. Remotely recurrent tumors resulted in a higher mortality and significantly harbored an 8q gain; astrocytomas with an 8q gain resulted in significantly shorter overall survival than those without an 8q gain. OncoScan ® arrays and next-generation sequencing revealed specific 8q regions (i.e., between 8q22 and 8q24) show a high copy number. In conclusion, only tumors with TP53 mutations showed patterns of remote recurrence in IDH mutant gliomas. Furthermore, an 8q gain was significantly associated with remote intracranial recurrence and can be considered a poor prognostic factor in astrocytomas, IDH-mutant.

  19. Analysis of mutation and promoter methylation of TP53 gene in tumors of the head and neck

    Directory of Open Access Journals (Sweden)

    Jarzynski Adrian

    2016-06-01

    Full Text Available According to current World Health Organization data, worldwide, cancer is second to cardiovascular diseases as the leading cause of death. The p53 protein is a translation product of the TP53 gene, and it has many functions in cells. Indeed, for this, it is commonly called the “guardian of the genome”. The aim of this study was to evaluate the prevalence of mutation and methylation in the promoter of the TP53 gene in cells affected with squamous cell carcinoma of the head and neck. The research material consisted of 34 DNA samples isolated from surgically removed tissue fragments of head and neck tumors. In this work, analysis of all samples for the presence of mutations proved negative. This result simultaneously revealed an absence of mutation in the TP53 gene promoter in the analyzed material. However, the detection of changes in the methylation profile status of the promoter of the TP53 gene in the DNA samples revealed the presence of both methylated alleles in 76.5% of the sample population, while in the remaining 23.5%, methylation was present in only one allele of the studied gene. In our work, we assumed that samples displaying methylation involving two alleles will show greater predisposition to the development of a malignant tumor. The obtained results reveal that despite the lack of mutation in the TP53 gene promoter, its functioning may be impaired by other mechanisms – either epigenetic or environmental.

  20. A new germline TP53 gene mutation in a family with Li-Fraumeni syndrome.

    Science.gov (United States)

    Dockhorn-Dworniczak, B; Wolff, J; Poremba, C; Schäfer, K L; Ritter, J; Gullotta, F; Jürgens, H; Böcker, W

    1996-07-01

    This report describes an unusual clinical presentation of Li-Fraumeni syndrome. Family history revealed a mild aggregation of adult cancers in one generation, and an unusual clustering of brain tumours of early childhood in the following generation. In order to evaluate the genetic basis for cancer predisposition in this family, molecular genetic analysis for the occurrence of germline TP53 tumour suppressor gene mutations was performed on 12 siblings of two generations. Indirect mutation analysis was performed by the single-strand conformation polymorphism (SSCP) technique. Alterations were characterised by automated direct fluorescence sequencing analysis. Tumour material was also examined for p53 protein accumulation by immunohistochemistry. Initially, a TP53 gene germline missense mutation was detected in an 11-year-old kindred with acute myeloid leukaemia (AML) following intensive treatment of a brain tumour. In peripheral blood and bone marrow samples of this proband, a reduction to hemizygosity occurred. During AML treatment, detection of LOH of 17p was used as a marker for clonality and treatment control. The mutation was found to be inherited from the proband's mother, who was diagnosed with breast cancer at the age of 48 years. Further, three siblings were carriers, and two are apparently healthy at the age of 21 and 23 years. Knowledge of germline mutations may allow accurate DNA-based carrier diagnosis which is of important clinical significance for treatment strategy and control. Furthermore, the occurrence of unaffected carriers in this family raises questions about appropriate methods of cancer surveillance and counselling for these people.

  1. BRCA1 and BRCA2 Mutations

    Science.gov (United States)

    patient education Fact Sheet PFS007: BRCA1 and BRCA2 Mutations OCTOBER 2017 BRCA1 and BRCA2 Mutations Cancer is caused by several different factors. A ... parent to child. Changes in genes are called mutations . Hereditary breast and ovarian cancer (HBOC) syndrome is ...

  2. Germline TP53 mutations and single nucleotide polymorphisms in children Mutaciones y polimorfismos de un único nucleótido del gen TP53 en línea germinal en niños

    Directory of Open Access Journals (Sweden)

    Pamela Valva

    2009-02-01

    Full Text Available Mutations in the gene TP53, which codifies the tumor suppressor protein p53, are found in about 50% of tumors. These mutations can occur not only at somatic level, but also in germline. Pediatric cancer patients, mostly with additional family history of malignancy, should be considered as potential TP53 germline mutation carriers. Germline TP53 mutations and polymorphisms have been widely studied to determine their relation with different tumors' pathogenesis. Our aim was to analyze the occurrence frequency of germline TP53 mutations and polymorphisms and to relate these to tumor development in a pediatric series. Peripheral blood mononuclear cell samples from 26 children with solid tumors [PST] and 21 pediatric healthy donors [HD] were analyzed for germline mutations and polymorphisms in TP53 gene spanning from exon 5 to 8 including introns 5 and 7. These PCR amplified fragments were sequenced to determine variations. A heterozygous mutation at codon 245 was found in 1/26 PST and 0/21 HD. Comparative polymorphisms distribution, at position 14181 and 14201(intron 7, between HD and PST revealed a trend of association (p= 0.07 with cancer risk. HD group disclosed a similar polymorphism distribution as published data for Caucasian and Central/South American populations. This is the first study about TP53 variant frequency and distribution in healthy individuals and cancer patients in Argentina.El gen que codifica para la proteína supresora de tumor p53 (TP53 se encuentra mutado en aproximadamente el 50% de los tumores. Estas mutaciones pueden presentarse como somáticas o en línea germinal. Los niños con tumores, sobre todo aquellos con historia familiar de enfermedad oncológica, deben considerarse potenciales portadores de mutaciones en línea germinal. Las mutaciones de TP53 y los polimorfismos son estudiados para determinar su relación con la patogénesis de diferentes tumores. El objetivo del trabajo fue analizar la frecuencia de

  3. Analysis of mutation and promoter methylation of TP53 gene in tumors of the head and neck

    OpenAIRE

    Jarzynski Adrian; Papiernik Katarzyna; Polz-Dacewicz Malgorzata

    2016-01-01

    According to current World Health Organization data, worldwide, cancer is second to cardiovascular diseases as the leading cause of death. The p53 protein is a translation product of the TP53 gene, and it has many functions in cells. Indeed, for this, it is commonly called the “guardian of the genome”. The aim of this study was to evaluate the prevalence of mutation and methylation in the promoter of the TP53 gene in cells affected with squamous cell carcinoma of the head and neck. The resear...

  4. Single nucleotide variation in the TP53 3' untranslated region in diffuse large B-cell lymphoma treated with rituximab-CHOP

    DEFF Research Database (Denmark)

    Li, Yong; Gordon, Michael W; Xu-Monette, Zijun Y

    2013-01-01

    We identified multiple single nucleotide variants (SNVs) in the TP53 3' untranslated region (3'UTR) in tumor specimens from 244 patients with diffuse large B-cell lymphoma (DLBCL). Patients carrying a wild-type TP53 coding sequence (CDS) and 1 or more 3'UTR SNVs had a better 5-year survival rate...... than patients carrying a wild-type CDS and the reference 3'UTR, yet there is no statistically significance difference in overall survival (OS). In contrast, 3'UTR variation predicted poorer OS for patients with a mutant TP53 CDS. We then sequenced TP53 3'UTR in 247 additional DLBCL patients...

  5. TP53 Mutation Status of Tubo-ovarian and Peritoneal High-grade Serous Carcinoma with a Wild-type p53 Immunostaining Pattern.

    Science.gov (United States)

    Na, Kiyong; Sung, Ji-Youn; Kim, Hyun-Soo

    2017-12-01

    Diffuse and strong nuclear p53 immunoreactivity and a complete lack of p53 expression are regarded as indicative of missense and nonsense mutations, respectively, of the TP53 gene. Tubo-ovarian and peritoneal high-grade serous carcinoma (HGSC) is characterized by aberrant p53 expression induced by a TP53 mutation. However, our experience with some HGSC cases with a wild-type p53 immunostaining pattern led us to comprehensively review previous cases and investigate the TP53 mutational status of the exceptional cases. We analyzed the immunophenotype of 153 cases of HGSC and performed TP53 gene sequencing analysis in those with a wild-type p53 immunostaining pattern. Immunostaining revealed that 109 (71.3%) cases displayed diffuse and strong p53 expression (missense mutation pattern), while 39 (25.5%) had no p53 expression (nonsense mutation pattern). The remaining five cases of HGSC showed a wild-type p53 immunostaining pattern. Direct sequencing analysis revealed that three of these cases harbored nonsense TP53 mutations and two had novel splice site deletions. TP53 mutation is almost invariably present in HGSC, and p53 immunostaining can be used as a surrogate marker of TP53 mutation. In cases with a wild-type p53 immunostaining pattern, direct sequencing for TP53 mutational status can be helpful to confirm the presence of a TP53 mutation. Copyright© 2017, International Institute of Anticancer Research (Dr. George J. Delinasios), All rights reserved.

  6. Inactivation of TP53 correlates with disease progression and low miR-34a expression in previously treated chronic lymphocytic leukemia patients

    DEFF Research Database (Denmark)

    Dufour, Annika; Palermo, Giuseppe; Zellmeier, Evelyn

    2013-01-01

    In chronic lymphocytic leukemia (CLL) patients, disruptions of the TP53 tumor suppressor pathway by 17p13 deletion (del17p), somatic TP53 mutations, or downregulation of microRNA-34a have been associated with a poor prognosis. So far, the impact of the various TP53 defects has not been evaluated...... in a large cohort of previously treated and relapsed CLL patients. Here, we present the results of TP53 gene sequencing and fluorescence in situ hybridization for del17p in a phase 3 clinical trial (REACH [Rituximab in the Study of Relapsed Chronic Lymphocytic Leukemia]). Of the 457 patients, 52 had TP53...... mutations and 37 had del17p. In 24 (46%) of the TP53 mutated patients, no del17p was found and in 9 of the del17p patients, no TP53 mutation was identified. Based on a predicted proportion of TP53 disruption, a complete disruption of TP53 function, either by a combination of point mutations and/or del17p...

  7. Missense mutations in the TP53 DNA-binding domain predict outcomes in patients with advanced oral cavity squamous cell carcinoma.

    Science.gov (United States)

    Lapke, Nina; Lu, Yen-Jung; Liao, Chun-Ta; Lee, Li-Yu; Lin, Chien-Yu; Wang, Hung-Ming; Ng, Shu-Hang; Chen, Shu-Jen; Yen, Tzu-Chen

    2016-07-12

    TP53 mutations have been linked to reduced survival in patients with oral cavity squamous cell carcinoma (OSCC). However, the impact of different types of TP53 mutations remains unclear. Here, we demonstrate that the carriage of missense mutations in the TP53 DNA binding domain (DBD missense mutations) is associated with decreased disease-specific survival (DSS) compared with wild-type TP53 (P=0.002) in a cohort of 345 OSCC patients. In contrast, DSS of patients bearing all of the remaining TP53 mutations did not differ from that observed in wild-type TP53 patients (P=0.955). Our classification method for TP53 mutations was superior to previously reported approaches (disruptive, truncating, Evolutionary Action score, mutations in L2/L3/LSH) for distinguishing between low- and high-risk patients. When analyzed in combination with traditional clinicopathological factors, TP53 DBD missense mutations were an independent prognostic factor for shorter DSS (P=0.014) alongside with advanced AJCC T- and N-classifications and the presence of extracapsular spread. A scoring system that included the four independent prognostic factors allowed a reliable patient stratification into distinct risk groups (high-risk patients, 16.2%). Our results demonstrate the usefulness of TP53 DBD missense mutations combined with clinicopathological factors for improving the prognostic stratification of OSCC patients.

  8. Combination of vorinostat and flavopiridol is selectively cytotoxic to multidrug-resistant neuroblastoma cell lines with mutant TP53.

    Science.gov (United States)

    Huang, Jen-Ming; Sheard, Michael A; Ji, Lingyun; Sposto, Richard; Keshelava, Nino

    2010-12-01

    As p53 loss of function (LOF) confers high-level drug resistance in neuroblastoma, p53-independent therapies might have superior activity in recurrent neuroblastoma. We tested the activity of vorinostat, a histone deacetylase inhibitor, and flavopiridol, a pan-Cdk inhibitor, in a panel of multidrug-resistant neuroblastoma cell lines that included lines with wild-type (wt) and transcriptionally active TP53 (n = 3), mutated (mt), and LOF TP53 (n = 4) or p14(ARF) deletion (n = 1). The combination of vorinostat and flavopiridol was synergistic and significantly more cytotoxic (P flavopiridol combination in CHLA-90. The combination caused reduction in the expression of G(2)/M proteins (cyclin B1, Mad2, MPM2) in 2 cell lines with mt TP53 but not in those with wt TP53. Plk1 expression was reduced in all treated lines. Small interfering RNA knockdown of Mad2 and cyclin B1 or Plk1 synergistically reduced the clonogenicity of CHLA-90 cells. The combination of HDAC inhibitor and flavopiridol may be a unique approach to treating neuroblastomas with p53 LOF, one that evokes induction of mitotic failure. ©2010 AACR.

  9. TP53 codon 72 polymorphism and cervical cancer : a pooled analysis of individual data from 49 studies

    NARCIS (Netherlands)

    Klug, Stefanie J.; Ressing, Meike; Koenig, Jochem; Abba, Martin C.; Agorastos, Theodoros; Brenna, Sylvia M. F.; Ciotti, Marco; Das, B. R.; Del Mistro, Annarosa; Dybikowska, Aleksandra; Giuliano, Anna R.; Gudleviciene, Zivile; Gyllensten, Ulf; Haws, Andrea L. F.; Helland, Aslaug; Herrington, C. Simon; Hildesheim, Alan; Humbey, Olivier; Jee, Sun H.; Kim, Jae Weon; Madeleine, Margaret M.; Menczer, Joseph; Ngan, Hextan Y. S.; Nishikawa, Akira; Niwa, Yoshimitsu; Pegoraro, Rosemary; Pillai, M. R.; Ranzani, Gulielmina; Rezza, Giovanni; Rosenthal, Adam N.; Roychoudhury, Susanta; Saranath, Dhananjaya; Schmitt, Virginia M.; Sengupta, Sharmila; Settheetham-Ishida, Wannapa; Shirasawa, Hiroshi; Snijders, Peter J. F.; Stoler, Mark H.; Suarez-Rincon, Angel E.; Szarka, Krisztina; Tachezy, Ruth; Ueda, Masatsugu; van der Zee, Ate G. J.; Doeberitz, Magnus von Knebel; Wu, Ming-Tsang; Yamashita, Tsuyoshi; Zehbe, Ingeborg; Blettner, Maria

    Background Cervical cancer is caused primarily by human papillomaviruses (HPV). The polymorphism rs1042522 at codon 72 of the TP53 tumour-suppressor gene has been investigated as a genetic cofactor. More than 80 studies were done between 1998 and 2006, after it was initially reported that women who

  10. DNA methylation patterns of candidate genes regulated by thymine DNA glycosylase in patients with TP53 germline mutations

    Energy Technology Data Exchange (ETDEWEB)

    Fortes, F.P. [CIPE, Laboratrio de Oncogentica Molecular, A.C. Camargo Cancer Center, São Paulo, SP (Brazil); Kuasne, H. [CIPE, Laboratrio NeoGene, A.C. Camargo Cancer Center, São Paulo, SP (Brazil); Departamento de Urologia, Faculdade de Medicina, Universidade Estadual Paulista, Botucatu, SP (Brazil); Marchi, F.A. [CIPE, Laboratrio NeoGene, A.C. Camargo Cancer Center, São Paulo, SP (Brazil); Programa Inter-Institucional em Bioinformtica, Instituto de Matemtica e Estatstica, Universidade So Paulo, So Paulo, SP (Brazil); Miranda, P.M. [CIPE, Laboratrio NeoGene, A.C. Camargo Cancer Center, São Paulo, SP (Brazil); Rogatto, S.R. [CIPE, Laboratrio NeoGene, A.C. Camargo Cancer Center, São Paulo, SP (Brazil); Departamento de Urologia, Faculdade de Medicina, Universidade Estadual Paulista, Botucatu, SP (Brazil); Achatz, M.I. [CIPE, Laboratrio de Oncogentica Molecular, A.C. Camargo Cancer Center, São Paulo, SP (Brazil); Departamento de Oncogentica, A.C. Camargo Cancer Center, So Paulo, SP (Brazil)

    2015-04-28

    Li-Fraumeni syndrome (LFS) is a rare, autosomal dominant, hereditary cancer predisposition disorder. In Brazil, the p.R337H TP53 founder mutation causes the variant form of LFS, Li-Fraumeni-like syndrome. The occurrence of cancer and age of disease onset are known to vary, even in patients carrying the same mutation, and several mechanisms such as genetic and epigenetic alterations may be involved in this variability. However, the extent of involvement of such events has not been clarified. It is well established that p53 regulates several pathways, including the thymine DNA glycosylase (TDG) pathway, which regulates the DNA methylation of several genes. This study aimed to identify the DNA methylation pattern of genes potentially related to the TDG pathway (CDKN2A, FOXA1, HOXD8, OCT4, SOX2, and SOX17) in 30 patients with germline TP53mutations, 10 patients with wild-type TP53, and 10 healthy individuals. We also evaluated TDG expression in patients with adrenocortical tumors (ADR) with and without the p.R337H TP53 mutation. Gene methylation patterns of peripheral blood DNA samples assessed by pyrosequencing revealed no significant differences between the three groups. However, increased TDG expression was observed by quantitative reverse transcription PCR in p.R337H carriers with ADR. Considering the rarity of this phenotype and the relevance of these findings, further studies using a larger sample set are necessary to confirm our results.

  11. DNA methylation patterns of candidate genes regulated by thymine DNA glycosylase in patients with TP53 germline mutations

    Directory of Open Access Journals (Sweden)

    F.P. Fortes

    2015-07-01

    Full Text Available Li-Fraumeni syndrome (LFS is a rare, autosomal dominant, hereditary cancer predisposition disorder. In Brazil, the p.R337H TP53 founder mutation causes the variant form of LFS, Li-Fraumeni-like syndrome. The occurrence of cancer and age of disease onset are known to vary, even in patients carrying the same mutation, and several mechanisms such as genetic and epigenetic alterations may be involved in this variability. However, the extent of involvement of such events has not been clarified. It is well established that p53 regulates several pathways, including the thymine DNA glycosylase (TDG pathway, which regulates the DNA methylation of several genes. This study aimed to identify the DNA methylation pattern of genes potentially related to the TDG pathway (CDKN2A, FOXA1, HOXD8, OCT4, SOX2, and SOX17 in 30 patients with germline TP53 mutations, 10 patients with wild-type TP53, and 10 healthy individuals. We also evaluated TDG expression in patients with adrenocortical tumors (ADR with and without the p.R337H TP53 mutation. Gene methylation patterns of peripheral blood DNA samples assessed by pyrosequencing revealed no significant differences between the three groups. However, increased TDG expression was observed by quantitative reverse transcription PCR in p.R337H carriers with ADR. Considering the rarity of this phenotype and the relevance of these findings, further studies using a larger sample set are necessary to confirm our results.

  12. A substantial proportion of microsatellite-unstable colon tumors carry TP53 mutations while not showing chromosomal instability

    NARCIS (Netherlands)

    Westra, JL; Boven, LG; van der Wes, P; Faber, H; Sikkema, B; Schaapveld, M; Dijkhuizen, T; Hollema, H; Buys, CHCM; Plukker, JTM; Kok, K; Hofstra, RMW

    Chromosomal instability in colon tumors implies the presence of numerical and structural chromosome aberrations and is further characterized by the absence of microsatellite instability and the occurrence of KRAS and/or TP53 mutations. In a previous screening of 194 colon tumors for both

  13. TP53 germline mutation may affect response to anticancer treatments: analysis of an intensively treated Li-Fraumeni family.

    Science.gov (United States)

    Kappel, Sonja; Janschek, Elisabeth; Wolf, Brigitte; Rudas, Margaretha; Teleky, Bela; Jakesz, Raimund; Kandioler, Daniela

    2015-06-01

    Li-Fraumeni syndrome (LFS) is a rare autosomal dominant inherited disorder associated with the occurrence of a wide spectrum of early-onset malignancies, the most prevalent being breast cancer and sarcoma. The presence of TP53 germline mutations in the majority of LFS patients suggests a genetic basis for the cancer predisposition. No special recommendations for the treatment of LFS patients have been made to date, except that of minimizing radiation. We hypothesized that TP53 germline mutations may be associated not only with cancer predisposition, but also with lack of response to chemo- and radiotherapy. Here, we present an Austrian LFS family whose members were intensively treated with chemo- and radiotherapy due to cancers that occurred at a predominantly young age, including eight breast cancers in six patients. Material from seven family members was screened for p53 mutation by Sanger sequencing and immunohistochemistry. A rare missense mutation in the tetramerization domain of exon 10 of the TP53 gene was found to segregate with malignant disease in this family. Lack of response to various chemotherapies and radiotherapy could be ascertained by histopathology of surgical specimens after neoadjuvant treatment, by cancer relapse occurring while receiving adjuvant systemic treatment and by the occurrence of second primaries in areas of adjuvant radiation. Our observations suggest that current standards of cancer treatment may not be valid for patients with LFS. In patients with TP53 germline mutation, cytotoxic treatment may bear not only the risk of tumor induction but also the risk of treatment failure.

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

    DEFF Research Database (Denmark)

    Stecher, C.W.; Hasle, H.; Grønbæk, Kirsten

    2008-01-01

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

  15. A meta-analysis of the relationship between FGFR3 and TP53 mutations in bladder cancer.

    Directory of Open Access Journals (Sweden)

    Yann Neuzillet

    Full Text Available TP53 and FGFR3 mutations are the most common mutations in bladder cancers. FGFR3 mutations are most frequent in low-grade low-stage tumours, whereas TP53 mutations are most frequent in high-grade high-stage tumours. Several studies have reported FGFR3 and TP53 mutations to be mutually exclusive events, whereas others have reported them to be independent. We carried out a meta-analysis of published findings for FGFR3 and TP53 mutations in bladder cancer (535 tumours, 6 publications and additional unpublished data for 382 tumours. TP53 and FGFR3 mutations were not independent events for all tumours considered together (OR = 0.25 [0.18-0.37], p = 0.0001 or for pT1 tumours alone (OR = 0.47 [0.28-0.79], p = 0.0009. However, if the analysis was restricted to pTa tumours or to muscle-invasive tumours alone, FGFR3 and TP53 mutations were independent events (OR = 0.56 [0.23-1.36] (p = 0.12 and OR = 0.99 [0.37-2.7] (p = 0.35, respectively. After stratification of the tumours by stage and grade, no dependence was detected in the five tumour groups considered (pTaG1 and pTaG2 together, pTaG3, pT1G2, pT1G3, pT2-4. These differences in findings can be attributed to the putative existence of two different pathways of tumour progression in bladder cancer: the CIS pathway, in which FGFR3 mutations are rare, and the Ta pathway, in which FGFR3 mutations are frequent. TP53 mutations occur at the earliest stage of the CIS pathway, whereas they occur would much later in the Ta pathway, at the T1G3 or muscle-invasive stage.

  16. A meta-analysis of the relationship between FGFR3 and TP53 mutations in bladder cancer.

    Science.gov (United States)

    Neuzillet, Yann; Paoletti, Xavier; Ouerhani, Slah; Mongiat-Artus, Pierre; Soliman, Hany; de The, Hugues; Sibony, Mathilde; Denoux, Yves; Molinie, Vincent; Herault, Aurélie; Lepage, May-Linda; Maille, Pascale; Renou, Audrey; Vordos, Dimitri; Abbou, Claude-Clément; Bakkar, Ashraf; Asselain, Bernard; Kourda, Nadia; El Gaaied, Amel; Leroy, Karen; Laplanche, Agnès; Benhamou, Simone; Lebret, Thierry; Allory, Yves; Radvanyi, François

    2012-01-01

    TP53 and FGFR3 mutations are the most common mutations in bladder cancers. FGFR3 mutations are most frequent in low-grade low-stage tumours, whereas TP53 mutations are most frequent in high-grade high-stage tumours. Several studies have reported FGFR3 and TP53 mutations to be mutually exclusive events, whereas others have reported them to be independent. We carried out a meta-analysis of published findings for FGFR3 and TP53 mutations in bladder cancer (535 tumours, 6 publications) and additional unpublished data for 382 tumours. TP53 and FGFR3 mutations were not independent events for all tumours considered together (OR = 0.25 [0.18-0.37], p = 0.0001) or for pT1 tumours alone (OR = 0.47 [0.28-0.79], p = 0.0009). However, if the analysis was restricted to pTa tumours or to muscle-invasive tumours alone, FGFR3 and TP53 mutations were independent events (OR = 0.56 [0.23-1.36] (p = 0.12) and OR = 0.99 [0.37-2.7] (p = 0.35), respectively). After stratification of the tumours by stage and grade, no dependence was detected in the five tumour groups considered (pTaG1 and pTaG2 together, pTaG3, pT1G2, pT1G3, pT2-4). These differences in findings can be attributed to the putative existence of two different pathways of tumour progression in bladder cancer: the CIS pathway, in which FGFR3 mutations are rare, and the Ta pathway, in which FGFR3 mutations are frequent. TP53 mutations occur at the earliest stage of the CIS pathway, whereas they occur would much later in the Ta pathway, at the T1G3 or muscle-invasive stage.

  17. TP53 codon 72 polymorphism in 12 populations of insular Southeast Asia and Oceania.

    Science.gov (United States)

    Kashima, Taeko; Makino, Kumiko; Soemantri, Augustinua; Ishida, Takafumi

    2007-01-01

    Distribution of a single nucleotide polymorphism in the TP53 codon 72 (Arg/Pro) was studied in Southeast Asia and Oceania where information about this polymorphism was lacking. A polymerase chain reaction restriction fragment length polymorphism method was employed to genotype a total of 733 subjects from 12 populations in insular Southeast Asia and Oceania. These populations have been classified as either an Austronesian-speaking group or Papuan-speaking group. The p53Arg frequencies ranged from 0.06 in the Seramese to 0.62 in the Kahayan with an average frequency of 0.38. No significant correlation between the p53Arg frequency and latitude was observed in the 12 populations tested (P > 0.05), whereas a significant correlation was obtained for the relationship between frequency and longitude among 9 Austronesian or the whole 12 populations tested (P < 0.01). A longitudinal cline of the p53Arg frequencies may reflect the history of the Austronesian's migration and local admixture with indigenous Papuan speakers who had probably harbored low p53Arg frequencies.

  18. Self-renewing Pten-/- TP53-/- protospheres produce metastatic adenocarcinoma cell lines with multipotent progenitor activity.

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    Wassim Abou-Kheir

    Full Text Available Prostate cancers of luminal adenocarcinoma histology display a range of clinical behaviors. Although most prostate cancers are slow-growing and indolent, a proportion is aggressive, developing metastasis and resistance to androgen deprivation treatment. One hypothesis is that a portion of aggressive cancers initiate from stem-like, androgen-independent tumor-propagating cells. Here we demonstrate the in vitro creation of a mouse cell line, selected for growth as self-renewing stem/progenitor cells, which manifests many in vivo properties of aggressive prostate cancer. Normal mouse prostate epithelium containing floxed Pten and TP53 alleles was subjected to CRE-mediated deletion in vitro followed by serial propagation as protospheres. A polyclonal cell line was established from dissociated protospheres and subsequently a clonal daughter line was derived. Both lines demonstrate a mature luminal phenotype in vitro. The established lines contain a stable minor population of progenitor cells with protosphere-forming ability and multi-lineage differentiation capacity. Both lines formed orthotopic adenocarcinoma tumors with metastatic potential to lung. Intracardiac inoculation resulted in brain and lung metastasis, while intra-tibial injection induced osteoblastic bone formation, recapitulating the bone metastatic phenotype of human prostate cancer. The cells showed androgen receptor dependent growth in vitro. Importantly, in vivo, the deprivation of androgens from established orthotopic tumors resulted in tumor regression and eventually castration-resistant growth. These data suggest that transformed prostate progenitor cells preferentially differentiate toward luminal cells and recapitulate many characteristics of the human disease.

  19. Metabolic activation of diesel exhaust carcinogens in primary and immortalized human TP53 knock-in (Hupki) mouse embryo fibroblasts.

    Science.gov (United States)

    Kucab, Jill E; Phillips, David H; Arlt, Volker M

    2012-04-01

    Approximately 50% of human tumors have a mutation in TP53. The pattern and spectra of TP53 mutations often differ between cancer types, perhaps due to different etiological factors. The Hupki (human TP53 knock-in) mouse embryo fibroblast (HUF) immortalization assay is useful for studying mutagenesis in the human TP53 gene by environmental carcinogens. Prior to initiating an immortalization assay, carcinogen treatment conditions must be optimized, which can require a large number of cells. As primary HUF cultures senesce within 2 weeks, restricting their use, we investigated whether immortalized HUFs retaining wild-type TP53 can be surrogates for primary HUFs in initial treatment optimization. DNA damage by eight compounds found in diesel exhaust, benzo[a]pyrene, 3-nitrobenzanthrone, 1-nitropyrene, 1,3-dinitropyrene, 1,6-dinitropyrene, 1,8-dinitropyrene, 6-nitrochrysene, and 3-nitrofluorene, was assessed by (32) P-postlabeling and the alkaline comet assay in primary HUFs and in an immortal HUF cell line J201. For most compounds, higher levels of DNA adducts accumulated in J201 cells than in primary HUFs. This difference was not reflected in the comet assay or by cell viability changes. Experiments in three additional immortal HUF cell lines (AAI49, U56, and E2-143) confirmed strong differences in DNA adduct levels compared with primary HUFs. However, these did not correlate with the protein expression of Nqo1 or Nat1/2, or with gene expression of Cyp1a1 or Cyp1b1. Our results show that using immortal HUFs as surrogates for primary HUFs in genotoxicity screening has limitations and that DNA adduct formation is the best measure of genotoxicity of the nitro-polycyclic aromatic hydrocarbons tested in HUFs. Copyright © 2011 Wiley Periodicals, Inc.

  20. Detection of mutant KRAS and TP53 DNA in circulating exosomes from healthy individuals and patients with pancreatic cancer.

    Science.gov (United States)

    Yang, Sujuan; Che, Sara P Y; Kurywchak, Paul; Tavormina, Jena L; Gansmo, Liv B; Correa de Sampaio, Pedro; Tachezy, Michael; Bockhorn, Maximilian; Gebauer, Florian; Haltom, Amanda R; Melo, Sonia A; LeBleu, Valerie S; Kalluri, Raghu

    2017-03-04

    Pancreatic cancer presents with a dismal mortality rate and is in urgent need of methods for early detection with potential for timely intervention. All living cells, including cancer cells, generate exosomes. We previously discovered double stranded genomic DNA in exosomes derived from the circulation of pancreatic cancer patients, which enabled the detection of prevalent mutations associated with the disease. Here, we report a proof-of-concept study that demonstrates the potential clinical utility of circulating exosomal DNA for identification of KRASG12D and TP53R273H mutations in patients with pancreas-associated pathologies, including pancreatic ductal adenocarcinoma (PDAC), chronic pancreatitis (CP) and intraductal papillary mucinous neoplasm (IPMN), and in healthy human subjects. In 48 clinically annotated serum samples from PDAC patients, digital PCR analyses of exosomal DNA identified KRASG12D mutation in 39.6% of cases, and TP53R273H mutation in 4.2% of cases. KRASG12D and TP53R273H mutations were also detected in exosomal DNA from IPMN patients (2 out of 7 with KRASG12D, one of which also co-presented with TP53R273H mutation). Circulating exosomal DNA in 5 out of 9 CP patients enabled the detection of KRASG12D mutation. In 114 healthy subject-derived circulating exosomal DNA, 2.6% presented with KRASG12D mutation and none with TP53R273H mutation. This study highlights the value of circulating exosomal DNA for a rapid, low-cost identification of cancer driving mutations. The identification of mutations in IPMN patients and healthy subjects suggests that liquid biopsies may allow potential assessment of cancer risk but with a cautionary note that detection of clinical cancer cannot be assumed.

  1. NM23-H1: a Metastasis-Associated Gene

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    Yi-Torng Tee

    2006-06-01

    Full Text Available The protein product of nm23-H1 gene has activity of nucleoside diphosphate (NDP kinase, which catalyzes the phosphorylation of nucleoside diphosphates to the corresponding nucleoside triphosphates. Reductions in nm23 expression have been significantly associated with aggressive behavior in melanoma, breast, colon, and gastric carcinomas. On the contrary, high levels of nm23 gene expression are noted in the advanced stage of thyroid carcinomas and associated with significant reductions in survival for neuroblastoma and osteosarcoma patients. Although expression of nm23/NDP kinase is divergent in various malignant tumors, its reduced expression seems to be related to increased metastatic potential in most carcinoma types. However, it is hypothesized that nm23 may play a tissue-specific role, and that different regulatory mechanisms may act in different tumors. In ovarian carcinoma, nm23-H1/NDP kinase may be correlated with some clinicopathologic characteristics. In cervical cancer, nm23-H1 is probably involved in cervical carcinogenesis and correlated with some aggressive parameters. Overexpression of nm23-H1 protein may indicate poor survival for cervical cancer patients. Other than histidine 118 residue (amino acid sequence 118: histidine concerned with NDP kinase activity of nm23-H1, serine 120 (amino acid sequence 120: serine related activity of histidine-dependent protein phosphotransfer was recently reported to be responsible for its biological suppressive effects. To inhibit metastatic potential, nm23-H1 is also demonstrated to co-immunoprecipitate the kinase suppressor of Ras and phosphorylate it, and therefore reduce activation of the extracellular signal-regulated kinase mitogen-activated protein kinase pathway in response to signaling.

  2. TP53 germline mutation testing in 180 families suspected of Li-Fraumeni syndrome: mutation detection rate and relative frequency of cancers in different familial phenotypes.

    NARCIS (Netherlands)

    Ruijs, M.W.; Verhoef, S.; Rookus, M.A.; Pruntel, R.; Hout, A.H. van der; Hogervorst, F.B.L.; Kluijt, I.; Sijmons, R.H.; Aalfs, C.M.; Wagner, A.; Ausems, M.G.E.M.; Hoogerbrugge-van der Linden, N.; Asperen, C.J. van; Gomez Garcia, E.B.; Meijers-Heijboer, H.; Kate, L.P. Ten; Menko, F.H.; Veer, L.J. van 't

    2010-01-01

    BACKGROUND Li-Fraumeni syndrome (LFS) is a rare autosomal dominant cancer predisposition syndrome. Most families fulfilling the classical diagnostic criteria harbour TP53 germline mutations. However, TP53 germline mutations may also occur in less obvious phenotypes. As a result, different criteria

  3. Association of the germline TP53 R72P and MDM2 SNP309 variants with breast cancer survival in specific breast tumor subgroups

    NARCIS (Netherlands)

    van den Broek, Alexandra J.; Broeks, Annegien; Horlings, Hugo M.; Canisius, Sander V. M.; Braaf, Linde M.; Langerød, Anita; van't Veer, Laura J.; Schmidt, Marjanka K.

    2011-01-01

    The tumor suppressor gene TP53 and its regulator MDM2 are both important players in the DNA-damage repair "TP53 response pathway". Common germline polymorphisms in these genes may affect outcome in patients with tumors characterized by additional somatic changes in the same or a related pathway. To

  4. SOX11 and TP53 add prognostic information to MIPI in a homogenously treated cohort of mantle cell lymphoma – a Nordic Lymphoma Group study

    DEFF Research Database (Denmark)

    Nordström, Lena; Sernbo, Sandra; Eden, Patrik

    2014-01-01

    an improved prognostic tool by combining the MIPI with information on molecular markers. SOX11 was shown to significantly add prognostic information to the MIPI, but in multivariate analysis TP53 was the only significant independent molecular marker. Based on these findings, we propose that TP53 and SOX11...

  5. TP53 mutations in de novo acute myeloid leukemia patients: longitudinal follow-ups show the mutation is stable during disease evolution.

    Science.gov (United States)

    Hou, H-A; Chou, W-C; Kuo, Y-Y; Liu, C-Y; Lin, L-I; Tseng, M-H; Chiang, Y-C; Liu, M-C; Liu, C-W; Tang, J-L; Yao, M; Li, C-C; Huang, S-Y; Ko, B-S; Hsu, S-C; Chen, C-Y; Lin, C-T; Wu, S-J; Tsay, W; Chen, Y-C; Tien, H-F

    2015-07-31

    The TP53 mutation is frequently detected in acute myeloid leukemia (AML) patients with complex karyotype (CK), but the stability of this mutation during the clinical course remains unclear. In this study, TP53 mutations were identified in 7% of 500 patients with de novo AML and 58.8% of patients with CK. TP53 mutations were closely associated with older age, lower white blood cell (WBC) and platelet counts, FAB M6 subtype, unfavorable-risk cytogenetics and CK, but negatively associated with NPM1 mutation, FLT3/ITD and DNMT3A mutation. Multivariate analysis demonstrated that TP53 mutation was an independent poor prognostic factor for overall survival and disease-free survival among the total cohort and the subgroup of patients with CK. A scoring system incorporating TP53 mutation and nine other prognostic factors, including age, WBC counts, cytogenetics and gene mutations, into survival analysis proved to be very useful to stratify AML patients. Sequential study of 420 samples showed that TP53 mutations were stable during AML evolution, whereas the mutation was acquired only in 1 of the 126 TP53 wild-type patients when therapy-related AML originated from different clone emerged. In conclusion, TP53 mutations are associated with distinct clinic-biological features and poor prognosis in de novo AML patients and are rather stable during disease progression.

  6. Cell cycle kinetics, apoptosis rates, DNA damage and TP53 gene expression in bladder cancer cells treated with allyl isothiocyanate (mustard essential oil).

    Science.gov (United States)

    Savio, André Luiz Ventura; da Silva, Glenda Nicioli; de Camargo, Elaine Aparecida; Salvadori, Daisy Maria Fávero

    2014-04-01

    Allyl isothiocyanate (AITC) is present in plants of the cruciferous family and is abundant in mustard seed. Due to its high bioavailability in urine after ingestion, AITC has been considered a promising antineoplastic agent against bladder cancer. Because TP53 mutations are the most common alterations in bladder cancer cells and are frequently detected in in situ carcinomas, in this study, we investigated whether the AITC effects in bladder cancer cells are dependent on the TP53 status. Two bladder transitional carcinoma cell lines were used: RT4, with wild-type TP53; and T24, mutated TP53 gene. AITC was tested at concentrations of 0.005, 0.0625, 0.0725, 0.0825, 0.0925, 0.125 and 0.25 μM in cytotoxicity, cell and clonogenic survival assays, comet and micronucleus assays and for its effects on cell cycle and apoptosis by flow cytometry and on TP53 gene expression. The data showed increased primary DNA damage in both cell lines; however, lower concentrations of AITC were able to induce genotoxicity in the mutant cells for the TP53 gene. Furthermore, the results demonstrated increased apoptosis and necrosis rates in the wild-type cells, but not in mutated TP53 cells, and cell cycle arrest in the G2 phase for mutated cells after AITC treatment. No significant differences were detected in TP53 gene expression in the two cell lines. In conclusion, AITC caused cell cycle arrest, increased apoptosis rates and varying genotoxicity dependent on the TP53 status. However, we cannot rule out the possibility that those differences could reflect other intrinsic genetic alterations in the examined cell lines, which may also carry mutations in genes other than TP53. Therefore, further studies using other molecular targets need to be performed to better understand the mechanisms by which AITC may exert its antineoplastic properties against tumor cells. Copyright © 2014 Elsevier B.V. All rights reserved.

  7. An extended Li-Fraumeni kindred with gastric carcinoma and a codon 175 mutation in TP53.

    Science.gov (United States)

    Varley, J M; McGown, G; Thorncroft, M; Tricker, K J; Teare, M D; Santibanez-Koref, M F; Martin, J; Birch, J M; Evans, D G

    1995-01-01

    We present an extended family with Li-Fraumeni syndrome characterised by gastric and breast carcinoma, glioma, sarcoma, and leukaemia. This family showed strong evidence of linkage to TP53, and three of four tumours analysed showed loss of the wild type allele. A codon 175 missense mutation was identified in exon 5 in all available affected subjects. Counselling, screening, and issues surrounding presymptomatic testing are discussed. Images PMID:8825920

  8. An extended Li-Fraumeni kindred with gastric carcinoma and a codon 175 mutation in TP53.

    OpenAIRE

    Varley, J. M.; McGown, G; Thorncroft, M.; Tricker, K. J.; Teare, M D; Santibanez-Koref, M F; Martin, J; Birch, J M; Evans, D. G.

    1995-01-01

    We present an extended family with Li-Fraumeni syndrome characterised by gastric and breast carcinoma, glioma, sarcoma, and leukaemia. This family showed strong evidence of linkage to TP53, and three of four tumours analysed showed loss of the wild type allele. A codon 175 missense mutation was identified in exon 5 in all available affected subjects. Counselling, screening, and issues surrounding presymptomatic testing are discussed.

  9. Detection of somatic TP53 mutations in tampons of patients with high-grade serous ovarian cancer.

    Science.gov (United States)

    Erickson, Britt K; Kinde, Isaac; Dobbin, Zachary C; Wang, Yuxuan; Martin, Jovana Y; Alvarez, Ronald D; Conner, Michael G; Huh, Warner K; Roden, Richard B S; Kinzler, Kenneth W; Papadopoulos, Nickolas; Vogelstein, Bert; Diaz, Luis A; Landen, Charles N

    2014-11-01

    To investigate whether tumor cells could be detected in the vagina of women with serous ovarian cancer through TP53 analysis of DNA samples collected by placement of a vaginal tampon. Women undergoing surgery for a pelvic mass were identified in the gynecologic oncology clinic. They placed a vaginal tampon before surgery, which was removed in the operating room. Cells were isolated and DNA was extracted from both the cells trapped within the tampon and the primary tumor. In patients with serous carcinoma, the DNA was interrogated for the presence of TP53 mutations using a method capable of detecting rare mutant alleles in a mixture of mutant and wild-type DNA. Thirty-three patients were enrolled. Eight patients with advanced serous ovarian cancer were included for analysis. Three had a prior tubal ligation. TP53 mutations were identified in all eight tumor samples. Analysis of the DNA from the tampons revealed mutations in three of the five patients with intact tubes (sensitivity 60%) and in none of the three patients with tubal ligation. In all three participants with mutation detected in the tampon specimen, the tumor and the vaginal DNA harbored the exact same TP53 mutation. The fraction of DNA derived from exfoliated tumor cells ranged from 0.01% to 0.07%. In this pilot study, DNA derived from tumor was detected in the vaginas of 60% of patients with ovarian cancer with intact fallopian tubes. With further development, this approach may hold promise for the early detection of this deadly disease.

  10. Distinct pattern of TP53 mutations in human immunodeficiency virus-related head and neck squamous cell carcinoma.

    Science.gov (United States)

    Gleber-Netto, Frederico O; Zhao, Mei; Trivedi, Sanchit; Wang, Jiping; Jasser, Samar; McDowell, Christina; Kadara, Humam; Zhang, Jiexin; Wang, Jing; William, William N; Lee, J Jack; Nguyen, Minh Ly; Pai, Sara I; Walline, Heather M; Shin, Dong M; Ferris, Robert L; Carey, Thomas E; Myers, Jeffrey N; Pickering, Curtis R

    2018-01-01

    Human immunodeficiency virus-infected individuals (HIVIIs) have a higher incidence of head and neck squamous cell carcinoma (HNSCC), and clinical and histopathological differences have been observed in their tumors in comparison with those of HNSCC patients without a human immunodeficiency virus (HIV) infection. The reasons for these differences are not clear, and molecular differences between HIV-related HNSCC and non-HIV-related HNSCC may exist. This study compared the mutational patterns of HIV-related HNSCC and non-HIV-related HNSCC. The DNA of 20 samples of HIV-related HNSCCs and 32 samples of non-HIV-related HNSCCs was sequenced. DNA libraries covering exons of 18 genes frequently mutated in HNSCC (AJUBA, CASP8, CCND1, CDKN2A, EGFR, FAT1, FBXW7, HLA-A, HRAS, KEAP1, NFE2L2, NOTCH1, NOTCH2, NSD1, PIK3CA, TGFBR2, TP53, and TP63) were prepared and sequenced on an Ion Personal Genome Machine sequencer. DNA sequencing data were analyzed with Ion Reporter software. The human papillomavirus (HPV) status of the tumor samples was assessed with in situ hybridization, the MassARRAY HPV multiplex polymerase chain reaction assay, and p16 immunostaining. Mutation calls were compared among the studied groups. HIV-related HNSCC revealed a distinct pattern of mutations in comparison with non-HIV-related HNSCC. TP53 mutation frequencies were significantly lower in HIV-related HNSCC. Mutations in HIV+ patients tended to be TpC>T nucleotide changes for all mutated genes but especially for TP53. HNSCC in HIVIIs presents a distinct pattern of genetic mutations, particularly in the TP53 gene. HIV-related HNSCC may have a distinct biology, and an effect of the HIV virus on the pathogenesis of these tumors should not be ruled out. Cancer 2018;124:84-94. © 2017 American Cancer Society. © 2017 American Cancer Society.

  11. Genotyping of Human Papillomavirus and TP53 Mutaions at Exons 5 to 7 in Lung Cancer Patients from Iran

    Directory of Open Access Journals (Sweden)

    Hossein Jafari

    2013-06-01

    Full Text Available Introduction: There is a powerful relationship between high-risk human papillomaviruses and lung cancer. In fact, inactivation of p53 is the most common genetic abnormality in lung cancer. Indeed, the frequency of HPV types and TP53 mutations in squamous cell carcinoma of lung, among patients from the northwest of Iran has been evaluated in this article. Methodes: Fifty Paraffin embedded blocks of lung SCC were selected for detection of HPV DNA by Nested PCR, and then DNA was sequenced for HPV typing. Equal numbers of positive and negative samples for the HPV DNA were examined for the presence of mutations in exons 5-7 of the TP53 gene by PCR and direct sequencing. Results: Overtly 9 (18% of 50 samples presented the HPV DNA: eight were HPV-18 and one was HPV-6. TP53 mutations were found in 5 samples (27.7%. Of these, 4 cases showed mutations in exon 5 and one case contained a mutation in exon 7.The most frequent mutation in exon 5 was the C to G transversion (c.409C>G, and also the T to A tansversion (c.770T>A in exon 7. Conclusion: This study showed that HPV-18 is more likely to conscequence in the development of lung cancer among some communities. Genetic alterations, alongside with environmental factors, all play a significant role in the pathogenesis of lung cancer.

  12. The T963C mutation of TP53 gene does not participate in the clonal origin of canine TVT.

    Science.gov (United States)

    Vázquez-Mota, N; Simón-Martínez, J; Córdova-Alarcon, E; Lagunes, L; Fajardo, R

    2008-02-01

    In dogs, the canine transmissible venereal tumor (CTVT) is the only neoplasm which is not produced by neoplastic transformation of normal cells; the tumor is transmitted from the affected dog to healthy dogs by implantation of one or various clones of cancer cells. Thus, the CTVT of dogs analyzed in various countries reveals similar genetic characteristics and consequently CTVT is considered to have a clonal origin. The CTVTs obtained from dogs in Korea showed the T963C mutation on TP53 gene; this mutation was thought to be a molecular alteration which participates in the origin of the ancestral clone, CTVT. Nonetheless, this supposed mutation has not been identified in other studies which were carried out for the purpose of clarifying the clonal origin of CTVT. Thus we have considered it important to identify the role of the T963C mutation of the TP53 gene in the clonal origin of CTVT in dogs. Consequently the region which includes the mutation of the TP53 gene in twenty samples of CTVT obtained from various canine breeds was PCR amplified and afterwards its sequence of nucleotides was determined. We conclude that this mutation did not participate in the clonal origin of the tumor, but was acquired at a later stage.

  13. The first two confirmed sub-Saharan African families with germline TP53 mutations causing Li-Fraumeni syndrome.

    Science.gov (United States)

    Macaulay, Shelley; Goodyear, Quintin Clive; Kruger, Mia; Chen, Wenlong; Essop, Fahmida; Krause, Amanda

    2018-02-01

    Li-Fraumeni syndrome is a rare inherited cancer syndrome characterised by the early onset of specific cancers. Li-Fraumeni syndrome (LFS) is associated with germline mutations in the tumour suppressor gene, TP53. This study reports the first cases of molecularly confirmed LFS germline mutations in sub-Saharan Africa. Three black African patients, all with LFS-associated cancers, were seen through the Clinical and Counselling Section of the Division of Human Genetics at the National Health Laboratory Service and University of the Witwatersrand in Johannesburg, South Africa, during 2011-2012. All three patients (two were related) were recruited into this research study. Sequence analysis of the coding region of the TP53 gene identified a Class IV (likely pathogenic) variant, c.326T > C (p.Phe109Ser), in the two related patients, and a known pathogenic mutation, c.1010G > A (p.Arg337His), also referred to as the Brazilian founder mutation, in the other patient. A confirmed diagnosis in these patients will assist in tailored medical management (it is recommended that individuals carrying a germline TP53 mutation avoid radiotherapy as this might cause secondary radiotherapy-induced malignancies) and in addition, genetic testing of at-risk family members can be offered. Very little is known and documented on LFS in African individuals. Despite the small number of patients in this study, the results support the need for diagnostic genetic testing for LFS in South Africa.

  14. TP53 status and taxane-platinum versus platinum-based therapy in ovarian cancer patients: A non-randomized retrospective study

    Directory of Open Access Journals (Sweden)

    Markowska Janina

    2008-01-01

    Full Text Available Abstract Background Taxane-platinum therapy (TP has replaced platinum-based therapy (PC or PAC, DNA damaging chemotherapy in the postoperative treatment of ovarian cancer patients; however, it is not always effective. TP53 protein plays a differential role in response to DNA-damaging agents and taxanes. We sought to define profiles of patients who benefit the most from TP and also of those who can be treated with PC. Methods We compared the effectiveness of PC/PAC (n = 253 and TP (n = 199 with respect to tumor TP53 accumulation in ovarian cancer patients with FIGO stage IIB-IV disease; this was a non-randomized retrospective study. Immunohistochemical analysis was performed on 452 archival tumors; univariate and multivariate analysis by the Cox's and logistic regression models was performed in all patients and in subgroups with [TP53(+] and without TP53 accumulation [TP53(-]. Results The advantage of taxane-platinum therapy over platinum-based therapy was seen in the TP53(+, and not in the TP53(- group. In the TP53(+ group taxane-platinum therapy enhanced the probability of complete remission (p = .018, platinum sensitivity (p = .014, platinum highly sensitive response (p = .038 and longer survival (OS, p = .008. Poor tumor differentiation diminished the advantage from taxane-platinum therapy in the TP53(+ group. In the TP53(- group PC/PAC was at least equally efficient as taxane-platinum therapy and it enhanced the chance of platinum highly sensitive response (p = .010. However, in the TP53(- group taxane-platinum therapy possibly diminished the risk of death in patients over 53 yrs (p = .077. Among factors that positively interacted with taxane-platinum therapy in some analyses were endometrioid and clear cell type, FIGO III stage, bulky residual tumor, more advanced age of patient and moderate tumor differentiation. Conclusion Our results suggest that taxane-platinum therapy is particularly justified in patients with TP53(+ tumors or older

  15. Alternative lengthening of telomeres is enriched in, and impacts survival of TP53 mutant pediatric malignant brain tumors.

    Science.gov (United States)

    Mangerel, Joshua; Price, Aryeh; Castelo-Branco, Pedro; Brzezinski, Jack; Buczkowicz, Pawel; Rakopoulos, Patricia; Merino, Diana; Baskin, Berivan; Wasserman, Jonathan; Mistry, Matthew; Barszczyk, Mark; Picard, Daniel; Mack, Stephen; Remke, Marc; Starkman, Hava; Elizabeth, Cynthia; Zhang, Cindy; Alon, Noa; Lees, Jodi; Andrulis, Irene L; Wunder, Jay S; Jabado, Nada; Johnston, Donna L; Rutka, James T; Dirks, Peter B; Bouffet, Eric; Taylor, Michael D; Huang, Annie; Malkin, David; Hawkins, Cynthia; Tabori, Uri

    2014-12-01

    Although telomeres are maintained in most cancers by telomerase activation, a subset of tumors utilize alternative lengthening of telomeres (ALT) to sustain self-renewal capacity. In order to study the prevalence and significance of ALT in childhood brain tumors we screened 517 pediatric brain tumors using the novel C-circle assay. We examined the association of ALT with alterations in genes found to segregate with specific histological phenotypes and with clinical outcome. ALT was detected almost exclusively in malignant tumors (p = 0.001). ALT was highly enriched in primitive neuroectodermal tumors (12 %), choroid plexus carcinomas (23 %) and high-grade gliomas (22 %). Furthermore, in contrast to adult gliomas, pediatric low grade gliomas which progressed to high-grade tumors did not exhibit the ALT phenotype. Somatic but not germline TP53 mutations were highly associated with ALT (p = 1.01 × 10(-8)). Of the other alterations examined, only ATRX point mutations and reduced expression were associated with the ALT phenotype (p = 0.0005). Interestingly, ALT attenuated the poor outcome conferred by TP53 mutations in specific pediatric brain tumors. Due to very poor prognosis, one year overall survival was quantified in malignant gliomas, while in children with choroid plexus carcinoma, five year overall survival was investigated. For children with TP53 mutant malignant gliomas, one year overall survival was 63 ± 12 and 23 ± 10 % for ALT positive and negative tumors, respectively (p = 0.03), while for children with TP53 mutant choroid plexus carcinomas, 5 years overall survival was 67 ± 19 and 27 ± 13 % for ALT positive and negative tumors, respectively (p = 0.07). These observations suggest that the presence of ALT is limited to a specific group of childhood brain cancers which harbor somatic TP53 mutations and may influence the outcome of these patients. Analysis of ALT may contribute to risk stratification and targeted therapies to

  16. A novel germline TP53 mutation p.Pro190Arg detected in a patient with lung and bilateral breast cancers.

    Science.gov (United States)

    Krześniak, Małgorzata; Butkiewicz, Dorota; Rachtan, Jadwiga; Matuszczyk, Iwona; Grzybowska, Ewa; Rusin, Marek

    2017-09-01

    Li-Fraumeni syndrome (LFS) is a rare genetic disease with strong predispositions to multiple early-onset neoplasms, mostly sarcomas, breast cancers, brain tumors and adrenocortical carcinomas (LFS core cancers). In most LFS families the germline mutations of TP53 tumor suppressor gene were found. Lung cancer does not belong to the core cancers of LFS, however its higher incidence is observed in families with TP53 mutations. Our aim was to search for TP53 mutations in female lung cancer patients whose clinico-demographic characteristics suggested a probable genetic predisposition to the disease. The coding region of TP53 from blood DNA was sequenced using Sanger method. The functioning of detected mutation was tested by luciferase reporter assay. We found a nucleotide substitution c.569C>G, p.Pro190Arg, which was not described in the TP53 germline mutation database (http://p53.iarc.fr/TP53GermlineMutations.aspx). The mutation destroys the ability of p53 to transactivate BAX promoter and significantly reduces transactivation potential of p53 toward the promoter of MDM2 gen. We identified novel germline mutation of TP53. Copyright © 2017 Medical University of Bialystok. Published by Elsevier B.V. All rights reserved.

  17. Predictive and prognostic impact of TP53 mutations and MDM2 promoter genotype in primary breast cancer patients treated with epirubicin or paclitaxel.

    Directory of Open Access Journals (Sweden)

    Ranjan Chrisanthar

    Full Text Available BACKGROUND: TP53 mutations have been associated with resistance to anthracyclines but not to taxanes in breast cancer patients. The MDM2 promoter single nucleotide polymorphism (SNP T309G increases MDM2 activity and may reduce wild-type p53 protein activity. Here, we explored the predictive and prognostic value of TP53 and CHEK2 mutation status together with MDM2 SNP309 genotype in stage III breast cancer patients receiving paclitaxel or epirubicin monotherapy. EXPERIMENTAL DESIGN: Each patient was randomly assigned to treatment with epirubicin 90 mg/m(2 (n = 109 or paclitaxel 200 mg/m(2 (n = 114 every 3rd week as monotherapy for 4-6 cycles. Patients obtaining a suboptimal response on first-line treatment requiring further chemotherapy received the opposite regimen. Time from last patient inclusion to follow-up censoring was 69 months. Each patient had snap-frozen tumor tissue specimens collected prior to commencing chemotherapy. PRINCIPAL FINDINGS: While TP53 and CHEK2 mutations predicted resistance to epirubicin, MDM2 status did not. Neither TP53/CHEK2 mutations nor MDM2 status was associated with paclitaxel response. Remarkably, TP53 mutations (p = 0.007 but also MDM2 309TG/GG genotype status (p = 0.012 were associated with a poor disease-specific survival among patients having paclitaxel but not patients having epirubicin first-line. The effect of MDM2 status was observed among individuals harbouring wild-type TP53 (p = 0.039 but not among individuals with TP53 mutated tumors (p>0.5. CONCLUSION: TP53 and CHEK2 mutations were associated with lack of response to epirubicin monotherapy. In contrast, TP53 mutations and MDM2 309G allele status conferred poor disease-specific survival among patients treated with primary paclitaxel but not epirubicin monotherapy.

  18. Polimorfismo do gene tp53 no códon 72 em pacientes com suspeita de LMC Codon 72 polymorphism of the TP53 gene in patients suspected to have CML

    Directory of Open Access Journals (Sweden)

    Camila S. Hamú

    2007-12-01

    Full Text Available A leucemia mielóide crônica (LMC é uma doença proliferativa do sistema hematopoiético, caracterizada pela expansão clonal de uma célula-tronco primitiva e pluripotente denominada stem cell. Este tipo de leucemia está associado, em 90% dos casos, à translocação t(9;22(q34;q11. Essa alteração cromossômica estrutural codifica para uma proteína quimérica BCR-ABL, que confere às células leucêmicas uma alta resistência à morte, independente do agente indutor desse processo. A proteína p53 é uma reguladora transcricional induzida por danos no DNA, fato que resulta na parada do ciclo celular com conseqüente ativação de mecanismos de reparo ou mesmo na indução à apoptose. As mutações no gene TP53 são as alterações genéticas mais comuns em tumores malignos humanos. O presente estudo teve como objetivo genotipar e determinar a freqüência alélica do polimorfismo do TP53 no códon 72 (arginina - Arg e prolina - Pro, em pacientes com suspeita de LMC, pela Reação em Cadeia da Polimerase. Desta forma, os resultados indicaram que 73,4% (23/30 dos pacientes apresentaram homozigose para arginina (Arg/Arg e 26,6% (7/30 heterozigose (Arg/Pro. Não foi encontrado nenhum paciente homozigoto para prolina (Pro/Pro. Os resultados obtidos sugerem que o polimorfismo do gene TP53 no códon 72 não é um fator de risco importante para a iniciação, promoção e progressão da LMC.Chronic myeloid leukemia (CML is a proliferative disorder of the hematopoietic system characterized by clonal expansion of a primitive and pluripotent stem cell. In this type of leukemia, up to 90% of all cases is associated to a specific chromosomal translocation, t(9;22(q34;q11. The genomic alteration results in a chimeric protein, BCR-ABL, that confers a high resistance leukemia cells to death, independent of the induction mechanism of this process. Protein p53 is a transcriptional factor expressed after DNA damage which ceases cell cycle progression and

  19. Identification of BRCA1-deficient ovarian cancers

    DEFF Research Database (Denmark)

    Skytte, Anne-Bine; Waldstrøm, Marianne; Rasmussen, Anders Aamann

    2011-01-01

    Objective. It is believed that 24 - 40% of ovarian cancers have dysfunction in the BRCA1 or BRCA2 (BRCAness) genes, either due to inherited or somatic mutations or due to epigenetic inactivation. Demonstration of ovarian cancers with BRCAness is becoming important both due to the possibility of o...

  20. Variants of cancer susceptibility genes in Korean BRCA1/2 mutation-negative patients with high risk for hereditary breast cancer.

    Science.gov (United States)

    Park, Ji Soo; Lee, Seung-Tae; Nam, Eun Ji; Han, Jung Woo; Lee, Jung-Yun; Kim, Jieun; Kim, Tae Il; Park, Hyung Seok

    2018-01-16

    We evaluated the incidence and spectrum of pathogenic and likely pathogenic variants of cancer susceptibility genes in BRCA1/2 mutation-negative Korean patients with a high risk for hereditary breast cancer using a comprehensive multigene panel that included 35 cancer susceptibility genes. Samples from 120 patients who were negative for BRCA1/2 mutations, but had been diagnosed with breast cancer that was likely hereditary, were prospectively evaluated for the prevalence of high-penetrance and moderate-penetrance germline mutations. Nine patients (7.5%) had at least one pathogenic or likely pathogenic variant. Ten variants were identified in these patients: TP53 in two patients, PALB2 in three patients, BARD1 in two patients, BRIP1 in two patients, and MRE11A in one patient. We also identified 30 types of 139 variants of unknown significance (VUS). High-penetrance germline mutations, including TP53 and PALB2, tended to occur with high frequency in young (cancer patients (4/19, 21.1%) than in those diagnosed with breast cancer at ≥35 years of age (1/101, 1.0%; p = 0.003). These combined results demonstrate that multigene panels offer an alternative strategy for identifying veiled pathogenic and likely pathogenic mutations in breast cancer susceptibility genes.

  1. BRCA 1-Mediated Histone Monoubiquitylation: Effect on Nucleosome Dynamics

    National Research Council Canada - National Science Library

    Zlatanova, Jordanka

    2008-01-01

    BRCA1, the protein product of the Breast Cancer Susceptibility Gene (BRCA1) has been implicated in multiple pathways that preserve genome stability, including cell cycle control, DNA repair, transcription, and chromatin remodeling...

  2. The frequency of cancer predisposition gene mutations in hereditary breast and ovarian cancer patients in Taiwan: From BRCA1/2 to multi-gene panels

    Science.gov (United States)

    Sung, Pi-Lin; Wen, Kuo-Chang; Chen, Yi-Jen; Chao, Ta-Chung; Tsai, Yi-Fang; Tseng, Ling-Ming; Qiu, Jian-Tai Timothy; Chao, Kuan-Chong; Wu, Hua-Hsi; Chuang, Chi-Mu

    2017-01-01

    An important role of genetic factors in the development of breast cancer (BC) or ovarian cancer (OC) in Taiwanese (ethnic Chinese) patients has been suggested. However, other than germline BRCA1 or BRCA2 mutations, which are related to hereditary breast-ovarian cancer (HBOC), cancer-predisposition genes have not been well studied in this population. The aim of the present study was to more accurately summarize the prevalence of genetic mutations in HBOC patients using various gene panels ranging in size from BRCA1/2 alone to multi-gene panels. Among 272 HBOC patients analyzed, the prevalence of BRCA1, BRCA2 and non-BRCA1/2 pathogenic mutations was 7.7% (21/272), 6.8% (16/236) and 8.2% (13/159), respectively. The total mutation rate was 18.4% (50/272). Although no founder mutations were identified in this study, two recurrent mutations, BRCA1 (c.3607C>T) and BRCA2 (c.5164_5165 delAG), were found. The main pathogenic/likely pathogenic mutations in non-BRCA1/2 genes included ATM, BRIP1, FANCI, MSH2, MUYTH, RAD50, RAD51C and TP53. The prevalence rate of gene mutations in HBOC patients did not differ with respect to whether BC or OC was the first diagnosis or they presented a family history of the disease or their age at diagnosis. HBOC patients with both BC and OC exhibited a higher prevalence rate of mutations (50.0%) than patients with OC (25.0%) or BC (8.6%) alone. In conclusion, evaluation of hereditary cancer risk in Taiwan HBOC patients, particularly individuals with double cancer, is strongly encouraged. Panel testing can yield additional genomic information, and widespread and well-designed panel testing will help in assessing more accurate mutational prevalence of risk genes. PMID:28961279

  3. The frequency of cancer predisposition gene mutations in hereditary breast and ovarian cancer patients in Taiwan: From BRCA1/2 to multi-gene panels.

    Science.gov (United States)

    Sung, Pi-Lin; Wen, Kuo-Chang; Chen, Yi-Jen; Chao, Ta-Chung; Tsai, Yi-Fang; Tseng, Ling-Ming; Qiu, Jian-Tai Timothy; Chao, Kuan-Chong; Wu, Hua-Hsi; Chuang, Chi-Mu; Wang, Peng-Hui; Huang, Chi-Ying F

    2017-01-01

    An important role of genetic factors in the development of breast cancer (BC) or ovarian cancer (OC) in Taiwanese (ethnic Chinese) patients has been suggested. However, other than germline BRCA1 or BRCA2 mutations, which are related to hereditary breast-ovarian cancer (HBOC), cancer-predisposition genes have not been well studied in this population. The aim of the present study was to more accurately summarize the prevalence of genetic mutations in HBOC patients using various gene panels ranging in size from BRCA1/2 alone to multi-gene panels. Among 272 HBOC patients analyzed, the prevalence of BRCA1, BRCA2 and non-BRCA1/2 pathogenic mutations was 7.7% (21/272), 6.8% (16/236) and 8.2% (13/159), respectively. The total mutation rate was 18.4% (50/272). Although no founder mutations were identified in this study, two recurrent mutations, BRCA1 (c.3607C>T) and BRCA2 (c.5164_5165 delAG), were found. The main pathogenic/likely pathogenic mutations in non-BRCA1/2 genes included ATM, BRIP1, FANCI, MSH2, MUYTH, RAD50, RAD51C and TP53. The prevalence rate of gene mutations in HBOC patients did not differ with respect to whether BC or OC was the first diagnosis or they presented a family history of the disease or their age at diagnosis. HBOC patients with both BC and OC exhibited a higher prevalence rate of mutations (50.0%) than patients with OC (25.0%) or BC (8.6%) alone. In conclusion, evaluation of hereditary cancer risk in Taiwan HBOC patients, particularly individuals with double cancer, is strongly encouraged. Panel testing can yield additional genomic information, and widespread and well-designed panel testing will help in assessing more accurate mutational prevalence of risk genes.

  4. Unscrambling the genomic chaos of osteosarcoma reveals extensive transcript fusion, recurrent rearrangements and frequent novel TP53 aberrations.

    Science.gov (United States)

    Lorenz, Susanne; Barøy, Tale; Sun, Jinchang; Nome, Torfinn; Vodák, Daniel; Bryne, Jan-Christian; Håkelien, Anne-Mari; Fernandez-Cuesta, Lynnette; Möhlendick, Birte; Rieder, Harald; Szuhai, Karoly; Zaikova, Olga; Ahlquist, Terje C; Thomassen, Gard O S; Skotheim, Rolf I; Lothe, Ragnhild A; Tarpey, Patrick S; Campbell, Peter; Flanagan, Adrienne; Myklebost, Ola; Meza-Zepeda, Leonardo A

    2016-02-02

    In contrast to many other sarcoma subtypes, the chaotic karyotypes of osteosarcoma have precluded the identification of pathognomonic translocations. We here report hundreds of genomic rearrangements in osteosarcoma cell lines, showing clear characteristics of microhomology-mediated break-induced replication (MMBIR) and end-joining repair (MMEJ) mechanisms. However, at RNA level, the majority of the fused transcripts did not correspond to genomic rearrangements, suggesting the involvement of trans-splicing, which was further supported by typical trans-splicing characteristics. By combining genomic and transcriptomic analysis, certain recurrent rearrangements were identified and further validated in patient biopsies, including a PMP22-ELOVL5 gene fusion, genomic structural variations affecting RB1, MTAP/CDKN2A and MDM2, and, most frequently, rearrangements involving TP53. Most cell lines (7/11) and a large fraction of tumor samples (10/25) showed TP53 rearrangements, in addition to somatic point mutations (6 patient samples, 1 cell line) and MDM2 amplifications (2 patient samples, 2 cell lines). The resulting inactivation of p53 was demonstrated by a deficiency of the radiation-induced DNA damage response. Thus, TP53 rearrangements are the major mechanism of p53 inactivation in osteosarcoma. Together with active MMBIR and MMEJ, this inactivation probably contributes to the exceptional chromosomal instability in these tumors. Although rampant rearrangements appear to be a phenotype of osteosarcomas, we demonstrate that among the huge number of probable passenger rearrangements, specific recurrent, possibly oncogenic, events are present. For the first time the genomic chaos of osteosarcoma is characterized so thoroughly and delivered new insights in mechanisms involved in osteosarcoma development and may contribute to new diagnostic and therapeutic strategies.

  5. Reduced rate of human papillomavirus infection and genetic overtransmission of TP53 72C polymorphic variant lower cervical cancer incidence.

    Science.gov (United States)

    Alsbeih, Ghazi A; Al-Harbi, Najla M; Bin Judia, Sara S; Khoja, Hatim A; Shoukri, Mohamed M; Tulbah, Asma M

    2017-07-01

    Cervical cancer is a predominantly human papillomavirus (HPV)-driven disease worldwide. However, its incidence is unexplainably low in western Asia, including Saudi Arabia. Using this paradigm, we investigated the role of HPV infection rate and host genetic predisposition in TP53 G72C single nucleotide polymorphism (SNP) presumed to affect cancer incidence. Patients treated between 1990 and 2012 were reviewed, and a series of 232 invasive cervical cancer cases were studied and compared with 313 matched controls without cancer. SNP was genotyped by way of direct sequencing. HPV linear array analysis was used to detect and genotype HPV in tumor samples. The incidence of cervical cancer revealed bimodal peaks at 42.5 years, with a slighter rebound at 60.8 years. Among all cases, 77% were HPV-positive and 16 HPV genotypes were detected-mostly genotypes 16 (75%) and 18 (9%)-with no difference by age, histology, or geographical region. Although the TP53 G72C genotype was not associated with overall cervical cancer risk, it was significantly associated with HPV positivity (odds ratio, 0.57; 95% confidence interval, 0.36-0.90; P = .016). Furthermore, the variant C allele was significantly overtransmitted in the population (P Cervical cancer incidence displays bimodal curve peaking at a young age with secondary rebound at older age. The combination of relative low HPV infection and variant TP53 72C allele overtransmission provide a plausible explanation for the low incidence of cervical cancer in our population. Therefore, HPV screening and host SNP genotyping may provide more relevant biomarkers to gauge the risk of developing cervical cancer. Cancer 2017;123:2459-66. © 2017 American Cancer Society. © 2017 The Authors. Cancer published by Wiley Periodicals, Inc. on behalf of American Cancer Society.

  6. CYP1A1, GSTM1, GSTT1 and TP53 Polymorphisms and Risk of Gallbladder Cancer in Bolivians.

    Science.gov (United States)

    Sakai, Kazuaki; Loza, Ernesto; Roig, Guido Villa-Gomez; Nozaki, Ryoko; Asai, Takao; Ikoma, Toshikazu; Tsuchiya, Yasuo; Kiyohara, Chikako; Yamamoto, Masaharu; Nakamura, Kazutoshi

    2016-01-01

    The Plurinational State of Bolivia (Bolivia) has a high incidence rate of gallbladder cancer (GBC). However, the genetic and environmental risk factors for GBC development are not well understood. We aimed to assess whether or not cytochrome P450 (CYP1A1), glutathione S-transferase mu 1 (GSTM1), theta 1 (GSTT1) and tumor suppressor protein p53 (TP53) genetic polymorphisms modulate GBC susceptibility in Bolivians. This case-control study covered 32 patients with GBC and 86 healthy subjects. GBC was diagnosed on the basis of histological analysis of tissues at the Instituto de Gastroenterologia Boliviano-Japones (IGBJ); the healthy subjects were members of the staff at the IGBJ. Distributions of the CYP1A1 rs1048943 and TP53 rs1042522 polymorphisms were assayed using PCR-restriction fragment length polymorphism assay. GSTM1 and GSTT1 deletion polymorphisms were detected by a multiplex PCR assay. The frequency of the GSTM1 null genotype was significantly higher in GBC patients than in the healthy subjects (odds ratio [OR], 2.35; 95% confidence interval [CI], 1.03-5.37; age-adjusted OR, 3.53; 95% CI, 1.29-9.66; age- and sex-adjusted OR, 3.40; 95% CI, 1.24-9.34). No significant differences were observed in the frequencies of CYP1A1, GSTT1, or TP53 polymorphisms between the two groups. The GSTM1 null genotype was associated with increased GBC risk in Bolivians. Additional studies with larger control and case populations are warranted to confirm the association between the GSTM1 deletion polymorphism and GBC risk suggested in the present study.

  7. Gene co-expression analyses differentiate networks associated with diverse cancers harbouring TP53 missense or null mutations

    Directory of Open Access Journals (Sweden)

    Kathleen Oros Klein

    2016-08-01

    Full Text Available In a variety of solid cancers, missense mutations in the well-established TP53 tumour suppressor gene may lead to presence of a partially-functioning protein molecule, whereas mutations affecting the protein encoding reading frame, often referred to as null mutations, result in the absence of p53 protein. Both types of mutations have been observed in the same cancer type. As the resulting tumour biology may be quite different between these two groups, we used RNA-sequencing data from The Cancer Genome Atlas (TCGA from four different cancers with poor prognosis, namely ovarian, breast, lung and skin cancers, to compare the patterns of co-expression of genes in tumours grouped according to their TP53 missense or null mutation status. We used Weighted Gene Coexpression Network analysis (WGCNA and a new test statistic built on differences between groups in the measures of gene connectivity. For each cancer, our analysis identified a set of genes showing differential coexpression patterns between the TP53 missense- and null mutation-carrying groups that was robust to the choice of the tuning parameter in WGCNA. After comparing these sets of genes across the four cancers, one gene (KIR3DL2 consistently showed differential coexpression patterns between the null and missense groups. KIR3DL2 is known to play an important role in regulating the immune response, which is consistent with our observation that this gene’s strongly-correlated partners implicated many immune-related pathways. Examining mutation-type-related changes in correlations between sets of genes may provide new insight into tumour biology.

  8. Breast cancer phenotype in women with TP53 germline mutations: a Li-Fraumeni syndrome consortium effort.

    Science.gov (United States)

    Masciari, Serena; Dillon, Deborah A; Rath, Michelle; Robson, Mark; Weitzel, Jeffrey N; Balmana, Judith; Gruber, Stephen B; Ford, James M; Euhus, David; Lebensohn, Alexandra; Telli, Melinda; Pochebit, Stephen M; Lypas, Georgios; Garber, Judy E

    2012-06-01

    Breast cancer is the most common tumor in women with Li-Fraumeni Syndrome (LFS), an inherited cancer syndrome associated with germline mutations in the TP53 tumor suppressor gene. Their lifetime breast cancer risk is 49% by age 60. Breast cancers in TP53 mutation carriers recently have more often been reported to be hormone receptor and HER-2 positive by immunohistochemistry and FISH in small series. We seek to complement the existing small literature with this report of a histopathologic analysis of breast cancers from women with documented LFS. Unstained slides and paraffin-embedded tumor blocks from breast cancers from 39 germline TP53 mutation carriers were assembled from investigators in the LFS consortium. Central histology review was performed on 93% of the specimens by a single breast pathologist from a major university hospital. Histology, grade, and hormone receptor status were assessed by immunohistochemistry; HER-2 status was defined by immunohistochemistry and/or FISH. The 43 tumors from 39 women comprise 32 invasive ductal carcinomas and 11 ductal carcinomas in situ (DCIS). No other histologies were observed. The median age at diagnosis was 32 years (range 22-46). Of the invasive cancers, 84% were positive for ER and/or PR; and 81% were high grade. Sixty three percent of invasive and 73% of in situ carcinomas were positive for Her2/neu (IHC 3+ or FISH amplified). Of the invasive tumors, 53% were positive for both ER and HER2+; other ER/PR/HER2 combinations were observed. The DCIS were positive for ER and HER2 in 27% of the cases. This report of the phenotype of breast cancers from women with LFS nearly doubles the literature on this topic. Most DCIS and invasive ductal carcinomas in LFS are hormone receptor positive and/or HER-2 positive. These findings suggest that modern treatments may result in improved outcomes for women with LFS-associated breast cancer.

  9. The profile and contribution of rare germline copy number variants to cancer risk in Li-Fraumeni patients negative for TP53 mutations

    OpenAIRE

    Silva, Amanda G; Krepischi, Ana Cristina Victorino; Pearson, Peter Lees; Hainaut, Pierre; Rosenberg, Carla; Achatz, Maria Isabel

    2014-01-01

    Background: The Li-Fraumeni syndrome (LFS) is an inherited rare cancer predisposition syndrome characterized by a variety of early-onset tumors. Although germline mutations in the tumor suppressor gene TP53 account for over 50% of the families matching LFS criteria, the lack of TP53 mutation in a significant proportion of LFS families, suggests that other types of inherited alterations must contribute to their cancer susceptibility. Recently, increases in copy number variation (CN...

  10. Identification of a novel germ-line mutation in the TP53 gene in a Mexican family with Li-Fraumeni syndrome

    OpenAIRE

    Taja-Chayeb, Lucia; Vidal-Mill?n, Silvia; Guti?rrez-Hern?ndez, Olga; Trejo-Becerril, Catalina; P?rez-C?rdenas, Enrique; Ch?vez-Blanco, Alma; de la Cruz-Hern?ndez, Erick; Due?as-Gonz?lez, Alfonso

    2009-01-01

    Abstract Background Germ-line mutations of the TP53 gene are known to cause Li-Fraumeni syndrome, an autosomal, dominantly inherited, high-penetrance cancer-predisposition syndrome characterized by the occurrence of a variety of cancers, mainly soft tissue sarcomas, adrenocortical carcinoma, leukemia, breast cancer, and brain tumors. Methods Mutation analysis was based on Denaturing high performance liquid chromatography (DHPLC) screening of exons 2-11 of the TP53 gene, sequencing, and clonin...

  11. An identical, complex TP53 mutation arising independently in two unrelated families with diverse cancer profiles: the complexity of interpreting cancer risk in carriers

    OpenAIRE

    Pinto, E M; Ribeiro, R C; Li, J; Taja-Chayeb, L; Carrasco, L F; de Lourdes Peña-Torres, M; Vidal-Millán, S; Maldonado-Mtz, H; Dueñas-González, A; McGregor, L; Zambetti, G P

    2012-01-01

    Most inherited TP53 mutations have been identified in individuals with a family cancer predisposition syndrome, in which the activity of p53 mutants is severely reduced. However, germline p53 mutants in children with ‘sporadic' adrenocortical or choroid plexus tumors exhibit a wide range of functional activity. Here, we demonstrate the occurrence of a complex germline TP53 mutation in two unrelated families with different cancer phenotypes, neither fulfilling the classic criteria for Li-Fraum...

  12. Refractory anemia with ring sideroblasts associated with i(17q) and mutation of the TP53 gene.

    Science.gov (United States)

    Lazarević, Vladimir; Djordjević, Vesna; Magić, Zvonko; Marisavljevic, Dragomir; Colović, Milica

    2002-07-01

    A patient with a myelodysplastic syndrome ([MDS], i.e., refractory anemia with ring sideroblasts [RARS]) and a rapidly fatal clinical course is presented. A cytogenetic analysis showed an isochromosome 17q as a sole abnormality in all metaphases. An association between RARS and i(17q) has not been reported. Furthermore, a mutation of the remaining TP53 gene in exon 6 was evidenced by a single strand conformation polymorphism technique. This unique case illustrates heterogeneity of phenotypic expression of a stem cell disorder in MDS and indicates precaution in classifying hematologic syndromes especially when morphology is correlated with specific cytogenetic changes.

  13. The profile and contribution of rare germline copy number variants to cancer risk in Li-Fraumeni patients negative for TP53 mutations.

    Science.gov (United States)

    Silva, Amanda G; Krepischi, Ana C V; Pearson, Peter L; Hainaut, Pierre; Rosenberg, Carla; Achatz, Maria Isabel

    2014-04-28

    The Li-Fraumeni syndrome (LFS) is an inherited rare cancer predisposition syndrome characterized by a variety of early-onset tumors. Although germline mutations in the tumor suppressor gene TP53 account for over 50% of the families matching LFS criteria, the lack of TP53 mutation in a significant proportion of LFS families, suggests that other types of inherited alterations must contribute to their cancer susceptibility. Recently, increases in copy number variation (CNV) have been reported in LFS individuals, and are also postulated to contribute to LFS phenotypic variability. Seventy probands from families fulfilling clinical criteria for either Li-Fraumeni or Li-Fraumeni-like (LFS/LFL) syndromes and negative for TP53 mutations were screened for germline CNVs. We found a significantly increased number of rare CNVs, which were smaller in size and presented higher gene density compared to the control group. These data were similar to the findings we reported previously on a cohort of patients with germline TP53 mutations, showing that LFS/LFL patients, regardless of their TP53 status, also share similar CNV profiles. These results, in conjunction with our previous analyses, suggest that both TP53-negative and positive LFS/LFL patients present a broad spectrum of germline genetic alterations affecting multiple loci, and that the genetic basis of LFS/LFL predisposition or penetrance in many cases might reside in germline transmission of CNVs.

  14. An identical, complex TP53 mutation arising independently in two unrelated families with diverse cancer profiles: the complexity of interpreting cancer risk in carriers.

    Science.gov (United States)

    Pinto, E M; Ribeiro, R C; Li, J; Taja-Chayeb, L; Carrasco, L F; de Lourdes Peña-Torres, M; Vidal-Millán, S; Maldonado-Mtz, H; Dueñas-González, A; McGregor, L; Zambetti, G P

    2012-02-20

    Most inherited TP53 mutations have been identified in individuals with a family cancer predisposition syndrome, in which the activity of p53 mutants is severely reduced. However, germline p53 mutants in children with 'sporadic' adrenocortical or choroid plexus tumors exhibit a wide range of functional activity. Here, we demonstrate the occurrence of a complex germline TP53 mutation in two unrelated families with different cancer phenotypes, neither fulfilling the classic criteria for Li-Fraumeni syndrome. The TP53 mutation consists of a duplication of 7 bp in exon 4, resulting in a frame shift and premature stop signal. Haplotype analysis indicated that the mutation arose independently in the two families. Analysis of the DNA secondary structure predicts the TP53 mutation occurred within a hairpin loop. Additional germline complex mutations occurring within the same region of exon 4 have been identified in the IARC database. Our findings suggest that certain TP53 regions are prone to intrinsic genetic alterations, possibly through defects in DNA replication or repair. Further, carriers of the same TP53 mutation can have diverse cancer profiles, illustrating the complexity of genetic counseling and risk prediction.

  15. BRCA1 and BRCA2 germline mutation analysis among Indian ...

    Indian Academy of Sciences (India)

    Mutations in the BRCA1 and BRCA2 genes profoundly increase the risk of developing breast and/or ovarian cancer among women. To explore the contribution of BRCA1 and BRCA2 mutations in the development of hereditary breast cancer among Indian women, we carried out mutation analysis of the BRCA1 and BRCA2 ...

  16. Tsc1-Tp53 loss induces mesothelioma in mice, and evidence for this mechanism in human mesothelioma

    Science.gov (United States)

    Guo, Yanan; Chirieac, Lucian R.; Bueno, Raphael; Pass, Harvey; Wu, Wenhao; Malinowska, Izabela A.; Kwiatkowski, David J.

    2014-01-01

    Mesothelioma is diagnosed in approximately 2,500 patients in the United States every year, most often arising in the pleural space, but also occurring as primary peritoneal mesothelioma. The vast majority of patients with mesothelioma die from their disease within 3 years. We developed a new mouse model of mesothelioma by bladder or intra-peritoneal injection of adenovirus Cre into mice with conditional alleles of each of Tp53 and Tsc1. Such mice began to develop malignant ascites about 6 months after injection, which was due to peritoneal mesothelioma, based on tumor morphology and immunohistochemical staining. Mesothelioma cell lines were established which showed loss of both Tsc1 and Tp53, with mTORC1 activation. Treatment of mice with malignant ascites due to mesothelioma with rapamycin led to a marked reduction in ascites, extended survival, and a 95–99% reduction in mesothelioma tumor volume, in comparison to vehicle-treated mice. To see if TSC1/TSC2 loss was a common genetic event in human mesothelioma, we examined 9 human mesothelioma cell lines, and found that 4 of 9 showed persistent activation of mTORC1 though none had loss of TSC1 or TSC2. A tissue microarray analysis of 198 human mesothelioma specimens showed that 33% of cases had reduced TSC2 expression and 60% showed activation of mTOR, indicating that mTOR activation is common in human mesothelioma and suggesting that it is a potential therapeutic target. PMID:23851502

  17. Analysis list: Brca1 [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available Brca1 Blood + mm9 http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/target/Brca1.1.tsv... http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/target/Brca1.5.tsv http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/target/Brca...1.10.tsv http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/colo/Brca1.Blood.tsv http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/colo/Blood.gml ...

  18. Substrates of the BRCA1-dependent ubiquitin ligase.

    Science.gov (United States)

    Starita, Lea M; Parvin, Jeffrey D

    2006-02-01

    Discovering the precise function of the breast and ovarian specific tumor suppressor, BRCA1, has proven to be quite complicated. It has been determined that BRCA1, together with BARD1, comprise an E3 ubiquitin ligase. Since it is now known that BRCA1 is an enzyme, the challenge for BRCA1 research is to learn how this enzymatic activity functions in normal breast and ovarian cells in order to suppress cancerous transformation. This review will survey the known ubiquitination substrates of BRCA1 and suggest how these reactions may influence the genomic stability and proliferation of breast cells.

  19. Hereditary predisposition to ovarian cancer, looking beyond BRCA1/BRCA2.

    Science.gov (United States)

    Minion, Lindsey E; Dolinsky, Jill S; Chase, Dana M; Dunlop, Charles L; Chao, Elizabeth C; Monk, Bradley J

    2015-04-01

    Genetic predisposition to ovarian cancer is well documented. With the advent of next generation sequencing, hereditary panel testing provides an efficient method for evaluating multiple genes simultaneously. Therefore, we sought to investigate the contribution of 19 genes identified in the literature as increasing the risk of hereditary breast and ovarian cancer (HBOC) in a BRCA1 and BRCA2 negative population of patients with a personal history of breast and/or ovarian cancer by means of a hereditary cancer panel. Subjects were referred for multi-gene panel testing between February 2012 and March 2014. Clinical data was ascertained from requisition forms. The incidence of pathogenic mutations (including likely pathogenic), and variant of unknown significance were then calculated for each gene and/or patient cohort. In this cohort of 911 subjects, panel testing identified 67 mutations. With 7.4% of subjects harboring a mutation on this multi-gene panel, the diagnostic yield was increased, compared to testing for BRCA1 and BRCA2 mutations alone. In the ovarian cancer probands, the most frequently mutated genes were BRIP1 (n=8; 1.72%) and MSH6 (n=6; 1.29%). In the breast cancer probands, mutations were most commonly observed in CHEK2 (n=9; 2.54%), ATM (n=3; 0.85%), and TP53 (n=3; 0.85%). Although further studies are needed to clarify the exact management of patients with a mutation in each gene, this study highlights information that can be captured with panel testing and provides support for incorporation of panel testing into clinical practice. Copyright © 2015. Published by Elsevier Inc.

  20. Acute lymphoblastic leukemia with low hypodiploid/near triploid karyotype is a specific clinical entity and exhibits a very high TP53 mutation frequency of 93%.

    Science.gov (United States)

    Mühlbacher, Verena; Zenger, Melanie; Schnittger, Susanne; Weissmann, Sandra; Kunze, Franziska; Kohlmann, Alexander; Bellos, Frauke; Kern, Wolfgang; Haferlach, Torsten; Haferlach, Claudia

    2014-06-01

    B lymphoblastic leukemia/lymphoma (ALL) are subdivided by the WHO classification into five subgroups defined by specific translocations and two further subgroups defined by the number of chromosomes. The hypodiploid subgroup is heterogeneous and comprises ALL with a chromosome number of karyotype, we performed chromosome banding analysis, FISH, array comparative genomic hybridization, and mutational analyses of FBXW7, NOTCH1, KRAS, NRAS, TP53, and IKZF1 in 29 cases. We observed a nonrandom pattern of chromosome losses, including chromosomes 3, 7, 13, 15, 16, and 17. A deletion encompassing the CDKN2A/B locus was the only recurrent structural abnormality. A duplication of the low hypodiploid karyotype occurred frequently, resulting in a near triploid karyotype based on the definition by merely counting chromosomes but in fact was a very low tetraploid chromosome set. Mutational analyses revealed no mutations in IKZF1, FBXW7, NOTCH1, and KRAS and only one mutation in NRAS. However, we discovered a high frequency of TP53 mutations in 93% (27/29) of cases. In 26/27 cases with TP53 mutation, the second TP53 allele was lost due to monosomy 17. Median overall survival was short (18.5 months), which might be related to the high frequency of TP53 alterations. Therefore, ALL with low hypodiploidy is characterized by a typical pattern of chromosome losses and a remarkably high TP53 mutation frequency. Our data suggest the introduction of a novel WHO entity within the B lymphoblastic leukemia/lymphoma group showing low hypodiploid/very low tetraploid karyotype and concomitant TP53 mutation. Copyright © 2014 Wiley Periodicals, Inc.

  1. Wee1 Kinase Inhibitor AZD1775 Radiosensitizes Hepatocellular Carcinoma Regardless of TP53 Mutational Status Through Induction of Replication Stress

    Energy Technology Data Exchange (ETDEWEB)

    Cuneo, Kyle C., E-mail: kcuneo@umich.edu; Morgan, Meredith A.; Davis, Mary A.; Parcels, Leslie A.; Parcels, Joshua; Karnak, David; Ryan, Caila; Liu, Na; Maybaum, Jonathan; Lawrence, Theodore S.

    2016-06-01

    Purpose: Wee1 kinase inhibitors are effective radiosensitizers in cells lacking a G{sub 1} checkpoint. In this study we examined the potential effect of Wee1 kinase inhibition on inducing replication stress in hepatocellular carcinoma (HCC). Methods and Materials: Five independent datasets from the Oncomine database comparing gene expression in HCC compared to normal tissue were combined and specific markers associated with Wee1 sensitivity were analyzed. We then performed a series of in vitro experiments to study the effect of Wee1 inhibition on irradiated HCC cell lines with varying p53 mutational status. Clonogenic survival assays and flow cytometry using anti-γH2AX and phospho-histone H3 antibodies with propidium iodide were performed to study the effect of AZD1775 on survival, cell cycle, and DNA repair. Additionally, nucleoside enriched medium was used to examine the effect of altering nucleotide pools on Wee1 targeted radiation sensitization. Results: Our analysis of the Oncomine database found high levels of CDK1 and other cell cycle regulators indicative of Wee1 sensitivity in HCC. In our in vitro experiments, treatment with AZD1775 radiosensitized and chemosensitized Hep3B, Huh7, and HepG2 cell lines and was associated with delayed resolution of γH2AX foci and the induction of pan-nuclear γH2AX staining. Wee1 inhibition attenuated radiation-induced G{sub 2} arrest in the Hep3B (TP53 null) and Huh7 (TP53 mutant) cell lines but not in the TP53 wild-type cell line HepG2. Supplementation with nucleosides reversed the radiation-sensitizing effect of AZD1775 and reduced the amount of cells with pan-nuclear γH2AX staining after radiation. Conclusions: Radiation sensitization with Wee1 inhibition occurs in cells regardless of their p53 mutational status. In this study we show for the first time that replication stress via the overconsumption of nucleotides plays an important role in AZD1775-induced radiation sensitization.

  2. Non-BRCA1/2 Breast Cancer Susceptibility Genes: A New Frontier with Clinical Consequences for Plastic Surgeons.

    Science.gov (United States)

    Frey, Jordan D; Salibian, Ara A; Schnabel, Freya R; Choi, Mihye; Karp, Nolan S

    2017-11-01

    Twenty percent of breast cancer cases may be related to a genetic mutation conferring an increased risk of malignancy. The most common and prominent breast cancer susceptibility genes are BRCA1 and BRCA2, found in nearly 40% of such cases. However, continued interest and investigation of cancer genetics has led to the identification of a myriad of different breast cancer susceptibility genes. Additional genes, each with unique significance and associated characteristics, continue to be recognized. Concurrently, advanced genetic testing, while still controversial, has become more accessible and cost-effective. As oncologic and reconstructive advances continue to be made in prophylactic breast reconstructive surgery, patients may present to plastic surgeons with an increasingly more diverse array of genetic diagnoses to discuss breast reconstruction. It is therefore imperative that plastic surgeons be familiar with these breast cancer susceptibility genes and their clinical implications. We, therefore, aim to review the most common non-BRCA1/2 breast cancer susceptibility genetic mutations in an effort to assist plastic surgeons in counseling and managing this unique patient population. Included in this review are syndromic breast cancer susceptibility genes such as TP53, PTEN, CDH1, and STK11, among others. Nonsyndromic breast cancer susceptibility genes herein reviewed include PALB2, CHEK2, and ataxia telangiectasia mutated gene. With this knowledge, plastic surgeons can play a central role in the diagnosis and comprehensive treatment, including successful breast reconstruction, of all patients carrying genetic mutations conferring increased risk for breast malignancies.

  3. Non-BRCA1/2 Breast Cancer Susceptibility Genes: A New Frontier with Clinical Consequences for Plastic Surgeons

    Directory of Open Access Journals (Sweden)

    Jordan D. Frey, MD

    2017-11-01

    Full Text Available Summary:. Twenty percent of breast cancer cases may be related to a genetic mutation conferring an increased risk of malignancy. The most common and prominent breast cancer susceptibility genes are BRCA1 and BRCA2, found in nearly 40% of such cases. However, continued interest and investigation of cancer genetics has led to the identification of a myriad of different breast cancer susceptibility genes. Additional genes, each with unique significance and associated characteristics, continue to be recognized. Concurrently, advanced genetic testing, while still controversial, has become more accessible and cost-effective. As oncologic and reconstructive advances continue to be made in prophylactic breast reconstructive surgery, patients may present to plastic surgeons with an increasingly more diverse array of genetic diagnoses to discuss breast reconstruction. It is therefore imperative that plastic surgeons be familiar with these breast cancer susceptibility genes and their clinical implications. We, therefore, aim to review the most common non-BRCA1/2 breast cancer susceptibility genetic mutations in an effort to assist plastic surgeons in counseling and managing this unique patient population. Included in this review are syndromic breast cancer susceptibility genes such as TP53, PTEN, CDH1, and STK11, among others. Nonsyndromic breast cancer susceptibility genes herein reviewed include PALB2, CHEK2, and ataxia telangiectasia mutated gene. With this knowledge, plastic surgeons can play a central role in the diagnosis and comprehensive treatment, including successful breast reconstruction, of all patients carrying genetic mutations conferring increased risk for breast malignancies.

  4. BRCA1-IRIS overexpression promotes formation of aggressive breast cancers.

    Directory of Open Access Journals (Sweden)

    Yoshiko Shimizu

    Full Text Available INTRODUCTION: Women with HER2(+ or triple negative/basal-like (TN/BL breast cancers succumb to their cancer rapidly due, in part to acquired Herceptin resistance and lack of TN/BL-targeted therapies. BRCA1-IRIS is a recently discovered, 1399 residue, BRCA1 locus alternative product, which while sharing 1365 residues with the full-length product of this tumor suppressor gene, BRCA1/p220, it has oncoprotein-like properties. Here, we examine whether BRCA1-IRIS is a valuable treatment target for HER2(+ and/or TN/BL tumors. METHODOLOGY/PRINCIPAL FINDINGS: Immunohistochemical staining of large cohort of human breast tumor samples using new monoclonal anti-BRCA1-IRIS antibody, followed by correlation of BRCA1-IRIS expression with that of AKT1, AKT2, p-AKT, survivin and BRCA1/p220, tumor status and age at diagnosis. Generation of subcutaneous tumors in SCID mice using human mammary epithelial (HME cells overexpressing TERT/LT/BRCA1-IRIS, followed by comparing AKT, survivin, and BRCA1/p220 expression, tumor status and aggressiveness in these tumors to that in tumors developed using TERT/LT/Ras(V12-overexpressing HME cells. Induction of primary and invasive rat mammary tumors using the carcinogen N-methyl-N-nitrosourea (NMU, followed by analysis of rat BRCA1-IRIS and ERα mRNA levels in these tumors. High BRCA1-IRIS expression was detected in the majority of human breast tumors analyzed, which was positively correlated with that of AKT1-, AKT2-, p-AKT-, survivin, but negatively with BRCA1/p220 expression. BRCA1-IRIS-positivity induced high-grade, early onset and metastatic HER2(+ or TN/BL tumors. TERT/LT/BRCA1-IRIS overexpressing HME cells formed invasive subcutaneous tumors that express high AKT1, AKT2, p-AKT and vimentin, but no CK19, p63 or BRCA1/p220. NMU-induced primary and invasive rat breast cancers expressed high levels of rat BRCA1-IRIS mRNA but low levels of rat ERα mRNA. CONCLUSION/SIGNIFICANCE: BRCA1-IRIS overexpression triggers aggressive

  5. Base damage, local sequence context and TP53 mutation hotspots: a molecular dynamics study of benzo[a]pyrene induced DNA distortion and mutability.

    Science.gov (United States)

    Menzies, Georgina E; Reed, Simon H; Brancale, Andrea; Lewis, Paul D

    2015-10-30

    The mutational pattern for the TP53 tumour suppressor gene in lung tumours differs to other cancer types by having a higher frequency of G:C>T:A transversions. The aetiology of this differing mutation pattern is still unknown. Benzo[a]pyrene,diol epoxide (BPDE) is a potent cigarette smoke carcinogen that forms guanine adducts at TP53 CpG mutation hotspot sites including codons 157, 158, 245, 248 and 273. We performed molecular modelling of BPDE-adducted TP53 duplex sequences to determine the degree of local distortion caused by adducts which could influence the ability of nucleotide excision repair. We show that BPDE adducted codon 157 has greater structural distortion than other TP53 G:C>T:A hotspot sites and that sequence context more distal to adjacent bases must influence local distortion. Using TP53 trinucleotide mutation signatures for lung cancer in smokers and non-smokers we further show that codons 157 and 273 have the highest mutation probability in smokers. Combining this information with adduct structural data we predict that G:C>T:A mutations at codon 157 in lung tumours of smokers are predominantly caused by BPDE. Our results provide insight into how different DNA sequence contexts show variability in DNA distortion at mutagen adduct sites that could compromise DNA repair at well characterized cancer related mutation hotspots. © The Author(s) 2015. Published by Oxford University Press on behalf of Nucleic Acids Research.

  6. The possible role of TP53 mutation status in the treatment of squamous cell carcinomas of the head and neck (HNSCC) with radiotherapy with different overall treatment times

    DEFF Research Database (Denmark)

    Eriksen, Jesper Grau; Alsner, Jan; Steiniche, Torben

    2005-01-01

    for the outcome of radiotherapy. PATIENTS AND METHODS: DNA extracted from 180 paraffin-embedded formalin-fixed pretreatment biopsies of HNSCC was screened for mutations in exon 4C-10 by denaturing high-pressure liquid chromatography (DHPLC) followed by sequencing. Treatment was 66-68Gy, 2Gy/fx with overall...... dysfunctional p53. Overall, mutations in TP53 were not associated with the endpoints. However, when dichotomising according to TP53 status and evaluating the effect of the overall treatment time then tumours with mutant TP53 did benefit from 6 instead of 5fx/wk regarding local control, P=0.005; RR: 0.33 (C.I 95......%:0.15-0.75) whereas WT-tumours did not (P=0.9). These observations were also reflected in the disease-specific and crude survival. CONCLUSIONS: If all patients were considered regardless of treatment schedule, then TP53-mutations were not related to local control or survival. However, mutations in TP53 may...

  7. Mucinous carcinoma of the colon in a 16-year-old Turkish boy with Bloom syndrome: cytogenetic, histopathologic, TP53 gene and protein expression studies.

    Science.gov (United States)

    Balci, S; Aktas, D

    1999-05-01

    A 17-year-old Turkish boy with Bloom syndrome (BS) developed mucinous carcinoma of the transverse colon. He was followed from 2 to 17 years of age. Increased sister chromatid exchanges (SCE) were observed, and he was diagnosed with BS at the age of 7. Sun-sensitive skin lesions were examined by skin biopsy, and histopathological studies of these lesions were done. During the follow-up period, an intraabdominal mass at the transverse colon was found, and mucinous carcinoma of colon was diagnosed at the age of 16. We examined TP53 protein expression from paraffin-embedded colon tissue of the patient with an immunohistochemical method. Polymerase chain reaction products of exons 4-9 of the TP53 gene were examined by SSCP. No evidence of overexpression of TP53 protein or mutations of the TP53 gene was observed. The patient in this report is the first case with a mucinous carcinoma of colon diagnosed at an early age in the Bloom Syndrome Registry. Based on our results, carcinoma of the colon in BS patient may occur earlier than 35 years of age and the TP53 gene may not be directly related to carcinoma in Bloom syndrome.

  8. Inherited germline TP53 mutation encodes a protein with an aberrant C-terminal motif in a case of pediatric adrenocortical tumor.

    Science.gov (United States)

    Pinto, Emilia M; Ribeiro, Raul C; Kletter, Gad B; Lawrence, John P; Jenkins, Jesse J; Wang, Jinling; Shurtleff, Sheila; McGregor, Lisa; Kriwacki, Richard W; Zambetti, Gerard P

    2011-03-01

    Childhood adrenocortical tumor (ACT), a very rare malignancy, has an annual worldwide incidence of about 0.3 per million children younger than 15 years. The association between inherited germline mutations of the TP53 gene and an increased predisposition to ACT was described in the context of the Li-Fraumeni syndrome. In fact, about two-thirds of children with ACT have a TP53 mutation. However, less than 10% of pediatric ACT cases occur in Li-Fraumeni syndrome, suggesting that inherited low-penetrance TP53 mutations play an important role in pediatric adrenal cortex tumorigenesis. We identified a novel inherited germline TP53 mutation affecting the acceptor splice site at intron 10 in a child with an ACT and no family history of cancer. The lack of family history of cancer and previous information about the carcinogenic potential of the mutation led us to further characterize it. Bioinformatics analysis showed that the non-natural and highly hydrophobic C-terminal segment of the frame-shifted mutant p53 protein may disrupt its tumor suppressor function by causing misfolding and aggregation. Our findings highlight the clinical and genetic counseling dilemmas that arise when an inherited TP53 mutation is found in a child with ACT without relatives with Li-Fraumeni-component tumors.

  9. Structure-Function Of The Tumor Suppressor BRCA1

    Directory of Open Access Journals (Sweden)

    Serena L. Clark

    2012-04-01

    Full Text Available BRCA1, a multi-domain protein, is mutated in a large percentage of hereditary breast and ovarian cancers. BRCA1 is most often mutated in three domains or regions: the N-terminal RING domain, exons 11-13, and the BRCT domain. The BRCA1 RING domain mediates interactions between BRCA1 and other proteins and is responsible for the E3 ubiquitin ligase activity of BRCA1. BRCA1 ubiquitinates several proteins with various functions. The BRCA1 BRCT domain binds to phosphoproteins with specific sequences recognized by both BRCA1 and ATM/ATR kinases. Structural studies of the RING and BRCT domains have revealed the molecular basis by which cancer causing mutations impact the functions of BRCA1. While no structural data is available for the amino acids encoded by exons 11-13, multiple binding sites and functional domains exist in this region. Many mutations in exons 11-13 have deleterious effects on the function of these domains. In this mini-review, we examine the structure-function relationships of the BRCA1 protein and the relevance to cancer progression.

  10. A porcine model system of BRCA1 driven breast cancer

    Directory of Open Access Journals (Sweden)

    Geoff eClark

    2015-08-01

    Full Text Available BRCA1 is a breast and ovarian tumor suppressor. Hereditary mutations in BRCA1 result in a predisposition to breast cancer, and BRCA1 expression is down-regulated in ~30% of sporadic cases. The function of BRCA1 remains poorly understood, but it appears to play an important role in DNA repair and the maintenance of genetic stability. Mouse models of BRCA1 deficiency have been developed in an attempt to understand the role of the gene in vivo. However, the subtle nature of BRCA1 function and the well-known discrepancies between human and murine breast cancer biology and genetics may limit the utility of mouse systems in defining the function of BRCA1 in cancer and validating the development of novel therapeutics for breast cancer. In contrast to mice, pig biological systems and cancer genetics appear to more closely resemble their human counterparts. To determine if BRCA1 inactivation in pig cells promotes their transformation and may serve as a model for the human disease, we developed an immortalized porcine breast cell line and stably inactivated BRCA1 using miRNA. The cell line developed characteristics of breast cancer stem cells and exhibited a transformed phenotype. These results validate the concept of using pigs as a model to study BRCA1 defects in breast cancer and establish the first porcine breast tumor cell line.

  11. Wilms tumor gene 1 (WT1), TP53, RAS/BRAF and KIT aberrations in testicular germ cell tumors.

    Science.gov (United States)

    Boublikova, L; Bakardjieva-Mihaylova, V; Skvarova Kramarzova, K; Kuzilkova, D; Dobiasova, A; Fiser, K; Stuchly, J; Kotrova, M; Buchler, T; Dusek, P; Grega, M; Rosova, B; Vernerova, Z; Klezl, P; Pesl, M; Zachoval, R; Krolupper, M; Kubecova, M; Stahalova, V; Abrahamova, J; Babjuk, M; Kodet, R; Trka, J

    2016-07-01

    Wilms tumor gene 1 (WT1), a zinc-finger transcription factor essential for testis development and function, along with other genes, was investigated for their role in the pathogenesis of testicular germ cell tumors (TGCT). In total, 284 TGCT and 100 control samples were investigated, including qPCR for WT1 expression and BRAF mutation, p53 immunohistochemistry detection, and massively parallel amplicon sequencing. WT1 was significantly (p genes, RAS/BRAF and WT1 mutations were frequent while significant TP53 and KIT variants were not detected (p = 0.0003). WT1 has been identified as a novel factor involved in TGCT pathogenesis, with a potential prognostic impact. Distinct biologic nature of the two types of relapses occurring in TGCT has been demonstrated. Differential mutation rate of the key TGCT-related genes has been documented. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  12. Gene panel sequencing in familial breast/ovarian cancer patients identifies multiple novel mutations also in genes others than BRCA1/2.

    Science.gov (United States)

    Kraus, Cornelia; Hoyer, Juliane; Vasileiou, Georgia; Wunderle, Marius; Lux, Michael P; Fasching, Peter A; Krumbiegel, Mandy; Uebe, Steffen; Reuter, Miriam; Beckmann, Matthias W; Reis, André

    2017-01-01

    Breast and ovarian cancer (BC/OC) predisposition has been attributed to a number of high- and moderate to low-penetrance susceptibility genes. With the advent of next generation sequencing (NGS) simultaneous testing of these genes has become feasible. In this monocentric study, we report results of panel-based screening of 14 BC/OC susceptibility genes (BRCA1, BRCA2, RAD51C, RAD51D, CHEK2, PALB2, ATM, NBN, CDH1, TP53, MLH1, MSH2, MSH6 and PMS2) in a group of 581 consecutive individuals from a German population with BC and/or OC fulfilling diagnostic criteria for BRCA1 and BRCA2 testing including 179 with a triple-negative tumor. Altogether we identified 106 deleterious mutations in 105 (18%) patients in 10 different genes, including seven different exon deletions. Of these 106 mutations, 16 (15%) were novel and only six were found in BRCA1/2. To further characterize mutations located in or nearby splicing consensus sites we performed RT-PCR analysis which allowed confirmation of pathogenicity in 7 of 9 mutations analyzed. In PALB2, we identified a deleterious variant in six cases. All but one were associated with early onset BC and a positive family history indicating that penetrance for PALB2 mutations is comparable to BRCA2. Overall, extended testing beyond BRCA1/2 identified a deleterious mutation in further 6% of patients. As a downside, 89 variants of uncertain significance were identified highlighting the need for comprehensive variant databases. In conclusion, panel testing yields more accurate information on genetic cancer risk than assessing BRCA1/2 alone and wide-spread testing will help improve penetrance assessment of variants in these risk genes. © 2016 UICC.

  13. Transitions at CpG dinucleotides, geographic clustering of TP53 mutations and food availability patterns in colorectal cancer.

    Directory of Open Access Journals (Sweden)

    Fabio Verginelli

    Full Text Available BACKGROUND: Colorectal cancer is mainly attributed to diet, but the role exerted by foods remains unclear because involved factors are extremely complex. Geography substantially impacts on foods. Correlations between international variation in colorectal cancer-associated mutation patterns and food availabilities could highlight the influence of foods on colorectal mutagenesis. METHODOLOGY: To test such hypothesis, we applied techniques based on hierarchical clustering, feature extraction and selection, and statistical pattern recognition to the analysis of 2,572 colorectal cancer-associated TP53 mutations from 12 countries/geographic areas. For food availabilities, we relied on data extracted from the Food Balance Sheets of the Food and Agriculture Organization of the United Nations. Dendrograms for mutation sites, mutation types and food patterns were constructed through Ward's hierarchical clustering algorithm and their stability was assessed evaluating silhouette values. Feature selection used entropy-based measures for similarity between clusterings, combined with principal component analysis by exhaustive and heuristic approaches. CONCLUSION/SIGNIFICANCE: Mutations clustered in two major geographic groups, one including only Western countries, the other Asia and parts of Europe. This was determined by variation in the frequency of transitions at CpGs, the most common mutation type. Higher frequencies of transitions at CpGs in the cluster that included only Western countries mainly reflected higher frequencies of mutations at CpG codons 175, 248 and 273, the three major TP53 hotspots. Pearson's correlation scores, computed between the principal components of the datamatrices for mutation types, food availability and mutation sites, demonstrated statistically significant correlations between transitions at CpGs and both mutation sites and availabilities of meat, milk, sweeteners and animal fats, the energy-dense foods at the basis of

  14. Combined analysis of smoking, TP53, and FGFR3 mutations in Tunisian patients with invasive and superficial high-grade bladder tumors.

    Science.gov (United States)

    Ouerhani, Slah; Rouissi, Kamel; Kourda, Nadia; Marrakchi, Raja; Bougatef, Karim; Riadh Ben Slama, Mohamed; Sfaxi, Mohamed; Chebil, Mohamed; Ben Jilani, Sarra; Benammar Elgaaied, Amel

    2009-12-01

    In our cohort, FGFR3 mutations were detected in 31.1% of bladder tumors and are associated with lower stage and grade. Concerning TP53, 62 mutations were found in tumors from 44 cases (48.88%) and are associated with advanced forms. The combined analysis of FGFR3 and TP53 mutations in our cohort showed an independent distribution. In addition, we have reported that FGFR3 mutations spectrum depends on the intensity of tobacco use (pack years: PY). Finally, we have found that the FGFR3wt/TP53mut genotype, which was associated with advanced bladder tumors; was overrepresented in light smokers (PY < 40) compared to nonsmoker patients (p =.01).

  15. Lack of association of the TP53BP1 Glu353Asp polymorphism with risk of cancer: a systematic review and meta-analysis.

    Directory of Open Access Journals (Sweden)

    Lei Liu

    Full Text Available OBJECTIVE: The TP53BP1 gene may be involved in the development of cancer through disrupting DNA repair. However, studies investigating the relationship between TP53BP1 Glu353Asp (rs560191 polymorphism and cancer yielded contradictory and inconclusive outcomes. In order to realize these ambiguous findings, a meta-analysis was performed to assess the association between the TP53BP1 Glu353Asp (rs560191 polymorphism and susceptibility to cancer. METHODS: We conducted a search of all English reports on studies for the association between the TP53BP1 Asp353Glu (rs560191 polymorphism and susceptibility to cancer using Medline, the Cochrane Library, EMbase, Web of Science, Google (scholar, and all Chinese reports were identified manually and on-line using CBMDisc, Chongqing VIP database, and CNKI database. The strict selection criteria and exclusion criteria were determined, and odds ratios (ORs with 95% confidence intervals (CIs were used to assess the strength of associations. The fixed or random effect model was selected based on the heterogeneity test among studies. Publication bias was estimated using funnel plots and Egger's regression test. RESULTS: A total of seven studies were included in the meta-analysis including 3,213 cases and 3,849 controls. The results indicated that the Glu353Asp (rs560191 polymorphism in TP53BP1 gene had no association with cancer risk for all genetic models. In the subgroup analysis, the results suggested that Glu353Asp polymorphism was not associated with the risk of cancer according to ethnicity, cancer type, genotyping method, adjusted with control or not, HWE and quality score. CONCLUSIONS: This meta-analysis suggested that the Glu353Asp (rs560191 polymorphism in TP53BP1 gene was not associated with risk of cancer.

  16. An extensive molecular cytogenetic characterization in high-risk chronic lymphocytic leukemia identifies karyotype aberrations and TP53 disruption as predictors of outcome and chemorefractoriness

    Science.gov (United States)

    Cavallari, Maurizio; Quaglia, Francesca Maria; Lista, Enrico; Urso, Antonio; Guardalben, Emanuele; Martinelli, Sara; Saccenti, Elena; Bassi, Cristian; Lupini, Laura; Bardi, Maria Antonella; Volta, Eleonora; Tammiso, Elisa; Melandri, Aurora; Negrini, Massimo

    2017-01-01

    We investigated whether karyotype analysis and mutational screening by next generation sequencing could predict outcome in 101 newly diagnosed chronic lymphocytic leukemia patients with high-risk features, as defined by the presence of unmutated IGHV gene and/or 11q22/17p13 deletion by FISH and/or TP53 mutations. Cytogenetic analysis showed favorable findings (normal karyotype and isolated 13q14 deletion) in 30 patients, unfavorable (complex karyotype and/or 17p13/11q22 deletion) in 34 cases and intermediate (all other abnormalities) in 36 cases. A complex karyotype was present in 21 patients. Mutations were detected in 56 cases and were associated with unmutated IGHV status (p = 0.040) and complex karyotype (p = 0.047). TP53 disruption (i.e. TP53 mutations and/or 17p13 deletion by FISH) correlated with the presence of ≥ 2 mutations (p = 0.001) and a complex karyotype (p = 0.012). By multivariate analysis, an advanced Binet stage (p karyotype (p = 0.001) predicted a shorter time to first treatment. TP53 disruption (p = 0.019) and the unfavorable karyotype (p = 0.028) predicted a worse overall survival. A shorter time to chemorefractoriness was associated with TP53 disruption (p = 0.001) and unfavorable karyotype (p = 0.025). Patients with both unfavorable karyotype and TP53 disruption presented a dismal outcome (median overall survival and time to chemorefractoriness of 28.7 and 15.0 months, respectively). In conclusion, karyotype analysis refines risk stratification in high-risk CLL patients and could identify a subset of patients with highly unfavorable outcome requiring alternative treatments. PMID:28427204

  17. Downregulated Expression of E-cadherin and TP53 in Patients with Gastric Diseases: the Involvement of H. pylori Infection and Its Virulence Markers.

    Science.gov (United States)

    Ferraz, Mariane Avante; Zabaglia, Luanna Munhoz; Pereira, Weendelly Nayara; Orcini, Wilson Aparecido; de Labio, Roger Willian; Caleman Neto, Agostinho; Wisnieski, Fernanda; Calcagno, Danielle Queiroz; Santos, Leonardo Caires; Assumpção, Paulo Pimentel; Burbano, Rommel Rodriguez; Artigiani, Ricardo; Smith, Marilia de Arruda Cardoso; Payão, Spencer Luiz Marques; Rasmussen, Lucas T

    2016-03-01

    Gastritis caused by infection with Helicobacter pylori is characterized by chronic inflammation and damage in gastric tissue, which is a main risk factor for gastric cancer. Associated with H. pylori, the TP53 gene tumor suppressor and the cell adhesion glycoprotein epithelial cadherin develop a relevant role in the integrity and carcinogenesis of the epithelium. We aimed to detection of H. pylori and its main virulence markers and measured the messenger RNA (mRNA) expression levels of E-cadherin and TP53 genes. The detection of H. pylori and its virulence markers, as well as the mRNA expression levels of E-cadherin and TP53 genes, were obtained for 161 samples of gastric biopsies including 37 with normal gastric tissue, 70 with gastritis, 24 from neoplastic tissue, and 27 from adjacent non-neoplastic by means of a quantitative real-time polymerase chain reaction. The mRNA expression levels of E-cadherin and TP53 were found to be decreased in patients with gastritis, independently of H. pylori infection. In samples from gastric patients, the neoplastic tissue showed an accentuated decrease of expression; on the other hand, the expression of E-cadherin was normal in adjacent non-neoplastic. No evidence was found of the involvement of the cagA and vacA genes in the decreased expression of E-cadherin and TP53. The process of carcinogenesis is complex, and the decrease of the E-cadherin gene expression and TP53 gene expression appears to contribute significantly.

  18. Expression of genes related to apoptosis, cell cycle and signaling pathways are independent of TP53 status in urinary bladder cancer cells.

    Science.gov (United States)

    da Silva, Glenda N; Evangelista, Adriane F; Magalhães, Danielle A; Macedo, Cláudia; Búfalo, Michelle C; Sakamoto-Hojo, Elza T; Passos, Geraldo A S; Salvadori, Daisy M F

    2011-08-01

    Urinary bladder cancer is the fourth most common malignancy in the Western world. Transitional cell carcinoma (TCC) is the most common subtype, accounting for about 90% of all bladder cancers. The TP53 gene plays an essential role in the regulation of the cell cycle and apoptosis and therefore contributes to cellular transformation and malignancy; however, little is known about the differential gene expression patterns in human tumors that present with the wild-type or mutated TP53 gene. Therefore, because gene profiling can provide new insights into the molecular biology of bladder cancer, the present study aimed to compare the molecular profiles of bladder cancer cell lines with different TP53 alleles, including the wild type (RT4) and two mutants (5637, with mutations in codons 280 and 72; and T24, a TP53 allele encoding an in-frame deletion of tyrosine 126). Unsupervised hierarchical clustering and gene networks were constructed based on data generated by cDNA microarrays using mRNA from the three cell lines. Differentially expressed genes related to the cell cycle, cell division, cell death, and cell proliferation were observed in the three cell lines. However, the cDNA microarray data did not cluster cell lines based on their TP53 allele. The gene profiles of the RT4 cells were more similar to those of T24 than to those of the 5637 cells. While the deregulation of both the cell cycle and the apoptotic pathways was particularly related to TCC, these alterations were not associated with the TP53 status.

  19. Frequently increased epidermal growth factor receptor (EGFR copy numbers and decreased BRCA1 mRNA expression in Japanese triple-negative breast cancers

    Directory of Open Access Journals (Sweden)

    Sugiura Hiroshi

    2008-10-01

    Full Text Available Abstract Background Triple-negative breast cancer (estrogen receptor-, progesterone receptor-, and HER2-negative (TNBC is a high risk breast cancer that lacks specific therapy targeting these proteins. Methods We studied 969 consecutive Japanese patients diagnosed with invasive breast cancer from January 1981 to December 2003, and selected TNBCs based on the immunohistochemical data. Analyses of epidermal growth factor receptor (EGFR gene mutations and amplification, and BRCA1 mRNA expression were performed on these samples using TaqMan PCR assays. The prognostic significance of TNBCs was also explored. Median follow-up was 8.3 years. Results A total of 110 (11.3% patients had TNBCs in our series. Genotyping of the EGFR gene was performed to detect 14 known EGFR mutations, but none was identified. However, EGFR gene copy number was increased in 21% of TNBCs, while only 2% of ER- and PgR-positive, HER2-negative tumors showed slightly increased EGFR gene copy numbers. Thirty-one percent of TNBCs stained positive for EGFR protein by immunohistochemistry. BRCA1 mRNA expression was also decreased in TNBCs compared with controls. Triple negativity was significantly associated with grade 3 tumors, TP53 protein accumulation, and high Ki67 expression. TNBC patients had shorter disease-free survival than non-TNBC in node-negative breast cancers. Conclusion TNBCs have an aggressive clinical course, and EGFR and BRCA1 might be candidate therapeutic targets in this disease.

  20. Análisis genético en APC, KRAS y TP53 en pacientes con cáncer de estómago y colon

    OpenAIRE

    Palacio-Rúa, K.A.; L.F. Isaza-Jiménez; Ahumada-Rodríguez, E.; H. Ceballos-García; Muñetón-Peña, C.M.

    2014-01-01

    Antecedentes: El cáncer de estómago (CE) y colorrectal (CCR) presentan altas tasas de incidencia y mortalidad en la población mundial. Estas 2 neoplasias se caracterizan por tener una gran heterogeneidad genética. Hasta el momento, no existen estudios moleculares que analicen las mutaciones en los genes APC, KRAS y TP53 en población colombiana/latinoamericana. Objetivo: Analizar mutaciones en los genes APC, KRAS y TP53 en 59 pacientes con CE y CCR mediante el secuenciamiento directo. Pa...

  1. Inherited germline TP53 mutation encodes a protein with an aberrant C-terminal motif in a case of pediatric adrenocortical tumor

    OpenAIRE

    Pinto, Emilia M.; Ribeiro, Raul C.; Kletter, Gad B.; Lawrence, John P.; Jenkins, Jesse J.; Wang, Jinling; Shurtleff, Sheila; McGregor, Lisa; Kriwacki, Richard W.; Zambetti, Gerard P.

    2010-01-01

    Childhood adrenocortical tumor (ACT), a very rare malignancy, has an annual worldwide incidence of about 0.3 per million children younger than 15 years. The association between inherited germline mutations of the TP53 gene and an increased predisposition to ACT was described in the context of the Li-Fraumeni syndrome. In fact, about two-thirds of children with ACT have a TP53 mutation. However, less than 10% of pediatric ACT cases occur in Li-Fraumeni syndrome, suggesting that inherited low-p...

  2. Mutational profile and prognostic significance of TP53 in diffuse large B-cell lymphoma patients treated with rituximab-CHOP

    DEFF Research Database (Denmark)

    Xu-Monette, Zijun Y; Wu, Lin; Visco, Carlo

    2012-01-01

    -CHOP-treated patients with either the germinal center B-cell or activated B-cell DLBCL subtypes. Furthermore, we identified the loop-sheet-helix and L3 motifs in the DNA-binding domain to be the most critical structures for maintaining p53 function. In contrast, TP53 deletion and loss of heterozygosity did not confer...... worse survival. If gene mutation data are not available, immunohistochemical analysis showing > 50% cells expressing p53 protein is a useful surrogate and was able to stratify patients with significantly different prognoses. We conclude that assessment of TP53 mutation status is important...

  3. BRCA1-mediated repression of select X chromosome genes

    Directory of Open Access Journals (Sweden)

    Ropers H Hilger

    2004-09-01

    Full Text Available Abstract Recently BRCA1 has been implicated in the regulation of gene expression from the X chromosome. In this study the influence of BRCA1 on expression of X chromosome genes was investigated. Complementary DNA microarrays were used to compare the expression levels of X chromosome genes in 18 BRCA1-associated ovarian cancers to those of the 13 "BRCA1-like" and 14 "BRCA2-like" sporadic tumors (as defined by previously reported expression profiling. Significance was determined using parametric statistics with P

  4. BRCA1 mutations in Brazilian patients

    Directory of Open Access Journals (Sweden)

    Juliano Javert Lourenço

    2004-01-01

    Full Text Available BRCA1 mutations are known to be responsible for the majority of hereditary breast and ovarian cancers in women with early onset and a family history of the disease. In this paper we present a mutational survey conducted in 47 Brazilian patients with breast/ovarian cancer, selected based on age at diagnosis, family history, tumor laterality, and presence of breast cancer in male patients. All 22 coding exons and intron-exon junctions were sequenced. Constitutional mutations were found in seven families, consisting of one insertion (insC5382 in exon 20 (four patients, one four base-pair deletion (3450-3453delCAAG in exon 11 resulting in a premature stop codon (one patient, one transition (IVS17+2T> C in intron 17 affecting a mRNA splicing site (one patient, and a C> T transition resulting in a stop-codon (Q1135X in exon 11 (one patient. The identification of these mutations which are associated to hereditary breast and ovarian cancers will contribute to the characterization of the mutational spectrum of BRCA1 and to the improvement of genetic counseling for familial breast/ovarian cancer patients in Brazil.

  5. BRCA1 mutation site may be linked with nuclear DNA ploidy in BRCA1-mutated ovarian carcinomas.

    Science.gov (United States)

    Aghmesheh, Morteza; Saxena, Akshat; Niknam, Farshid

    2015-06-01

    BRCA1 has a role in maintaining normal nuclear DNA content during cell division and its inactivation may result in DNA aneuploidy and cancer progression. BRCA1-linked breast cancers are more aneuploid and have a worse prognosis, but this has not been elucidated in ovarian cancers. This study explores the potential difference in ploidy status between BRCA1-mutated and sporadic ovarian carcinomas. It also explores the potential association between BRCA1 mutation site and DNA ploidy status. This study compared DNA ploidy status of tumor blocks from 23 BRCA1-mutated ovarian carcinomas with that of 23 sporadic ovarian carcinomas matched for histologic subtype, patient age, stage and grade. DNA content of the nuclei was measured by Feulgen-Schiff staining followed by image cytometry and compared. BRCA1-linked tumors with a stop codon closer to the N-terminal (between 1 and 500 aa; 6/6, 100%) had a significantly higher frequency of nondiploidy compared with those with stop codon above 500 aa (7/12, 58%) (P = 0.033). A diploid peak was detected in 28% of BRCA1-mutated ovarian cancers and in 33% of sporadic ovarian cancers. The present study concluded that ovarian tumors with mutations closer to the N-terminal of BRCA1 may have a higher risk of DNA aneuploidy. There is no significant difference between BRCA1-mutated and sporadic ovarian carcinomas with respect to the DNA content. © 2014 Wiley Publishing Asia Pty Ltd.

  6. Impact of KRAS and TP53 mutations on survival in patients with left- and right-sided Dukes' C colon cancer

    NARCIS (Netherlands)

    Bleeker, W A; Hayes, V M; Karrenbeld, A; Hofstra, R M; Hermans, J; Buys, C C; Plukker, J T

    2000-01-01

    OBJECTIVE: It has been suggested that KRAS and TP53 mutated tumors might influence the phenotypic behavior of left- and right-sided colon tumors. We investigated the incidence of these mutations in left- and right-sided colon tumors and their possible influence on survival in a homogeneous group of

  7. Prognostic significance of K-ras and TP53 mutations in the role of adjuvant chemotherapy on survival in patients with Dukes C colon cancer

    NARCIS (Netherlands)

    Bleeker, W A; Hayes, V M; Karrenbeld, A; Hofstra, R M; Verlind, E; Hermans, J; Poppema, S; Buys, C H; Plukker, J T

    PURPOSE: Mutations in K-ras and TP53 genes are common in colorectal cancer. They affect biologic behavior and might influence chemotherapy susceptibility in these tumors. We investigated whether the survival of patients with Dukes C colon cancer treated with adjuvant chemotherapy is influenced by

  8. A comparison among HER2, TP53, PAI-1, angiogenesis, and proliferation activity as prognostic variables in tumours from 408 patients diagnosed with early breast cancer

    DEFF Research Database (Denmark)

    Offersen, Birgitte Vrou; Alsner, Jan; Ege Olsen, Karen

    2008-01-01

    BACKGROUND: The prognostic potential of HER2, TP53 mutations, PAI-1 protein levels, angiogenesis and proliferation were investigated in tumours from 408 patients with early breast cancer followed >10 years. One hundred and sixty seven patients (41%) died from breast cancer. MATERIALS AND METHODS:...

  9. The role of HPV RNA transcription, immune response-related gene expression and disruptive TP53 mutations in diagnostic and prognostic profiling of head and neck cancer.

    Science.gov (United States)

    Wichmann, Gunnar; Rosolowski, Maciej; Krohn, Knut; Kreuz, Markus; Boehm, Andreas; Reiche, Anett; Scharrer, Ulrike; Halama, Dirk; Bertolini, Julia; Bauer, Ulrike; Holzinger, Dana; Pawlita, Michael; Hess, Jochen; Engel, Christoph; Hasenclever, Dirk; Scholz, Markus; Ahnert, Peter; Kirsten, Holger; Hemprich, Alexander; Wittekind, Christian; Herbarth, Olf; Horn, Friedemann; Dietz, Andreas; Loeffler, Markus

    2015-12-15

    Stratification of head and neck squamous cell carcinomas (HNSCC) based on HPV16 DNA and RNA status, gene expression patterns, and mutated candidate genes may facilitate patient treatment decision. We characterize head and neck squamous cell carcinomas (HNSCC) with different HPV16 DNA and RNA (E6*I) status from 290 consecutively recruited patients by gene expression profiling and targeted sequencing of 50 genes. We show that tumors with transcriptionally inactive HPV16 (DNA+ RNA-) are similar to HPV-negative (DNA-) tumors regarding gene expression and frequency of TP53 mutations (47%, 8/17 and 43%, 72/167, respectively). We also find that an immune response-related gene expression cluster is associated with lymph node metastasis, independent of HPV16 status and that disruptive TP53 mutations are associated with lymph node metastasis in HPV16 DNA- tumors. We validate each of these associations in another large data set. Four gene expression clusters which we identify differ moderately but significantly in overall survival. Our findings underscore the importance of measuring the HPV16 RNA (E6*I) and TP53-mutation status for patient stratification and identify associations of an immune response-related gene expression cluster and TP53 mutations with lymph node metastasis in HNSCC. © 2015 UICC.

  10. TP53 hotspot mutations are predictive of survival in primary central nervous system lymphoma patients treated with combination chemotherapy

    DEFF Research Database (Denmark)

    Munch-Petersen, Helga D; Asmar, Fazila; Dimopoulos, Konstantinos

    2016-01-01

    patients. In a total of 107 PCNSL patients clinical data were recorded, histopathology reassessed, and genetic and epigenetic aberrations of the p53-miR34-DAPK network studied. TP53 mutational status (exon 5-8), with structural classification of single nucleotide variations according to the IARC-TP53......-Database, methylation status of MIR34A/B/C and DAPK, and p53-protein expression were assessed. The 57/107 (53.2 %) patients that were treated with combination chemotherapy +/- rituximab (CCT-treated) had a significantly better median overall survival (OS) (31.3 months) than patients treated with other...... patients with no influence on survival. Combined MUT-TP53 and MIR34A methylation was associated with poor PFS (median 6.4 versus 38.0 months), P = 0.0070. This study suggests that disruption of the p53-pathway by MUT-TP53in hotspot/direct DNA contact codons is predictive of outcome in CCT-treated PCNSL...

  11. Low Variability and Stable Frequency of Common Haplotypes of the TP53 Gene Region in Colorectal Cancer Patients in a Slovak Population.

    Science.gov (United States)

    Škereňová, Mária; Halašová, Erika; Matáková, Tatiana; Jesenská, Ľubica; Jurečeková, Jana; Šarlinová, Miroslava; Čierny, Daniel; Dobrota, Dušan

    2017-04-01

    To test the association between common TP53 haplotypes and colorectal cancer (CRC) development. A total of 277 CRC patients and 167 healthy volunteers were included in the study. Common TP53 haplotypes were estimated from eight single-nucleotide polymorphisms (SNPs) (rs1614984, rs77697176, rs12947788, rs1800372, rs2909430, rs1042522, rs17878362 and rs11652704). Stepwise haplotype trend regression showed the haplotype-regressor cccgaRDa as a possible predictive marker. The rare haplotype cccgaRDa was identified in 10 CRC cases and 3 controls. Although it is approximately twice as common in CRC (odds ratio (OR)=2.068; 95% confidence interval (CI)=0.471-9.069), the cccgaRDa haplotype frequency is low in the studied groups. Results of our study suggest that the common TP53 variability is relatively low (only 3 haplotypes occurred above 10%). The haplotype background of TP53 gene is relative stable and despite low haplotype-regressor cccgaRDa frequency it shows to be a possible predictive parameter for CRC development. Copyright© 2017, International Institute of Anticancer Research (Dr. George J. Delinasios), All rights reserved.

  12. Radiomics Strategy for Molecular Subtype Stratification of Lower-Grade Glioma: Detecting IDH and TP53 Mutations Based on Multimodal MRI.

    Science.gov (United States)

    Zhang, Xi; Tian, Qiang; Wang, Liang; Liu, Yang; Li, Baojuan; Liang, Zhengrong; Gao, Peng; Zheng, Kaizhong; Zhao, Bofeng; Lu, Hongbing

    2018-02-02

    Noninvasive detection of isocitrate dehydrogenase (IDH) and TP53 mutations are meaningful for molecular stratification of lower-grade gliomas (LrGG). To explore potential MRI features reflecting IDH and TP53 mutations of LrGG, and propose a radiomics strategy for detecting them. Retrospective, radiomics. A total of 103 LrGG patients were separated into development (n = 73) and validation (n = 30) cohorts. T 1 -weighted (before and after contrast-enhanced), T 2 -weighted, and fluid-attenuation inversion recovery images from 1.5T (n = 37) or 3T (n = 66) scanners. After data preprocessing, high-throughput features were derived from patients' volumes of interests of different sequences. The support vector machine-based recursive feature elimination (SVM-RFE) was adopted to find the optimal features for IDH and TP53 mutation detection. SVM models were trained and tested on development and validation cohort. The commonly used metric was used for assessing the efficiency. One-way analysis of variance (ANOVA), chi-square, or Fisher's exact test were applied on clinical characteristics to confirm whether significant differences exist between three molecular subtypes decided by IDH and TP53 status. Intraclass correlation coefficients were calculated to assess the robustness of the radiomics features. The constituent ratio of histopathologic subtypes was significantly different among three molecular subtypes (P = 0.017). SVM models for detecting IDH and TP53 mutation were established using 12 and 22 optimal features selected by SVM-RFE. The accuracies and area under the curves for IDH and TP53 mutations on the development cohort were 84.9%, 0.830, and 92.0%, 0.949, while on the validation cohort were 80.0%, 0.792, and 85.0%, 0.869, respectively. Furthermore, the stratified accuracies of three subtypes were 72.8%, 71.9%, and 70%, respectively. Using a radiomics approach integrating SVM model and multimodal MRI features, molecular subtype stratification of

  13. Distinct claudin expression characterizes BRCA1-related breast cancer

    NARCIS (Netherlands)

    van Voss, Marise R. Heerma; van Diest, Paul J.; Smolders, Yvonne H. C. M.; Bart, Joost; van der Wall, Elsken; van der Groep, Petra

    2014-01-01

    AimsMembers of the claudin family are involved in cancer progression and are differentially expressed in subtypes of breast cancer. Breast cancers in BRCA1 germ line mutation carriers have distinct clinicopathological characteristics. Biomarkers that discriminate between BRCA1-related and sporadic

  14. BRCA1 in the DNA damage response and at telomeres

    Directory of Open Access Journals (Sweden)

    Eliot Michael Rosen

    2013-06-01

    Full Text Available Abstract. Mutations of the breast and ovarian cancer susceptibility gene 1 (BRCA1 account for about 40-45% of hereditary breast cancer cases. Moreover, a significant fraction of sporadic (non-hereditary breast and ovarian cancers exhibit reduced or absent expression of the BRCA1 protein, suggesting an additional role for BRCA1 in sporadic cancers. BRCA1 follows the classic pattern of a highly penetrant Knudsen-type tumor suppressor gene in which one allele is inactivated through a germ-line mutation and the other is mutated or deleted within the tumor. BRCA1 is a multi-functional protein but it is not fully understood which function(s is (are most important for tumor suppression, nor is it clear why BRCA1 mutations confer a high risk for breast and ovarian cancers and not a broad spectrum of tumor types. Here, we will review BRCA1 functions in the DNA damage response (DDR, which are likely to contribute to tumor suppression. In the process, we will highlight some of the controversies and unresolved issues in the field. We will also describe a recently identified and under-investigated role for BRCA1 in the regulation of telomeres and the implications of this role in the DDR and cancer suppression.

  15. BRCA1 Reflects Myocardial Adverse Remodeling in Idiopathic Dilated Cardiomyopathy.

    Science.gov (United States)

    Nozynski, J K; Konecka-Mrowka, D; Zakliczynski, M; Zembala-Nozynska, E; Lange, D; Zembala, M

    2016-06-01

    The role of BRCA1 in chronic ischemic episodes seems to be pivotal for adverse remodeling and development of ischemic cardiomyopathy, because of its role in DNA repair and apoptosis. The aim of this study was to investigate the role of BRCA-1 in idiopathic dilated cardiomyopathy (IDCM). The study group (IDCM) comprised myocardial samples from hearts explanted before transplantation owing to IDCM in 10 males (age 44 ± 5.3 years) without clinical symptoms of ischemic heart disease. The control group consisted myocardial fragments taken from 10 male heart valve and pulmonary artery donors with diagnosed cerebral death (age 40 ± 2.3 years). BRCA1 was detected immunohistochemically with rabbit anti-BRCA1 polyclonal antibody. The intensity of BRCA1 expression was semiquantitatively assessed for cardiocytes, small vessels including capillaries, and interstitial cells. The significances between groups were estimated using the Mann-Whitney U test. All IDCM cases were positive and presented nonuniform BRCA1 expression: hypertrophied cardiocytes showed very intense staining and typical cardiomyopathic cardiocytes were stained weakly forming mosaic. Control cases showed weak-to-moderate uniform staining. Intensity of staining was significantly higher in IDCM cardiocytes, whereas small vessels and interstitial were stained similarly in both groups. IDCM adverse remodeling results in more intense but nonuniform BRCA1 expression. This phenomenon seems to reflect IDCM biology: lower BRCA1 expression in myocytes with lower anti-apoptotic and DNA damage repair activity, with the opposite in hypertrophied myofibers. Copyright © 2016 Elsevier Inc. All rights reserved.

  16. BRCA1/2 mutation analysis in 41 ovarian cell lines reveals only one functionally deleterious BRCA1 mutation.

    LENUS (Irish Health Repository)

    Stordal, Britta

    2013-06-01

    Mutations in BRCA1\\/2 increase the risk of developing breast and ovarian cancer. Germline BRCA1\\/2 mutations occur in 8.6-13.7% of unselected epithelial ovarian cancers, somatic mutations are also frequent. BRCA1\\/2 mutated or dysfunctional cells may be sensitive to PARP inhibition by synthetic lethality. The aim of this study is to comprehensively characterise the BRCA1\\/2 status of a large panel of ovarian cancer cell lines available to the research community to assist in biomarker studies of novel drugs and in particular of PARP inhibitors. The BRCA1\\/2 genes were sequenced in 41 ovarian cell lines, mRNA expression of BRCA1\\/2 and gene methylation status of BRCA1 was also examined. The cytotoxicity of PARP inhibitors olaparib and veliparib was examined in 20 cell lines. The cell line SNU-251 has a deleterious BRCA1 mutation at 5564G > A, and is the only deleterious BRCA1\\/2 mutant in the panel. Two cell lines (UPN-251 and PEO1) had deleterious mutations as well as additional reversion mutations that restored the protein functionality. Heterozygous mutations in BRCA1\\/2 were relatively common, found in 14.6% of cell lines. BRCA1 was methylated in two cell lines (OVCAR8, A1847) and there was a corresponding decrease in gene expression. The BRCA1 methylated cell lines were more sensitive to PARP inhibition than wild-type cells. The SNU-251 deleterious mutant was more sensitive to PARP inhibition, but only in a long-term exposure to correct for its slow growth rate. Cell lines derived from metastatic disease are significantly more resistant to veliparib (2.0 fold p = 0.03) compared to those derived from primary tumours. Resistance to olaparib and veliparib was correlated Pearsons-R 0.5393, p = 0.0311. The incidence of BRCA1\\/2 deleterious mutations 1\\/41 cell lines derived from 33 different patients (3.0%) is much lower than the population incidence. The reversion mutations and high frequency of heterozygous mutations suggest that there is a selective

  17. BRCA1 promoter methylation of normal breast epithelial cells as a possible precursor for BRCA1-methylated breast cancer

    Science.gov (United States)

    Otani, Yoko; Miyake, Tomohiro; Kagara, Naofumi; Shimoda, Masafumi; Naoi, Yasuto; Maruyama, Naomi; Shimomura, Atsuhi; Shimazu, Kenzo; Kim, Seung Jin; Noguchi, Shinzaburo

    2014-01-01

    The breast cancer susceptibility gene 1 (BRCA1) and glutathione S-transferase P1 (GSTP1) promoters are reportedly often methylated in breast cancer tissues. Their methylation status in surrounding normal breast tissues has not been examined thoroughly although this may well be important for a better understanding of breast carcinogenesis. In this study, BRCA1 and GSTP1 promoter methylation was examined by methylation-specific PCR assay. Patients with BRCA1-methylated (n = 15) or BRCA1-unmethylated (n = 15) tumors and those with GSTP1-methylated (n = 9) or GSTP1-unmethylated (n = 11) tumors were included in the present study. Methylation status of manually micro-dissected normal epithelial cells from the formalin-fixed paraffin-embedded sections of normal breast tissues adjacent to and distant from the tumors was examined at multiple sites (n = 1–5). Of the 15 patients with BRCA1-methylated tumors, 9 harbored BRCA1 promoter methylation in at least one site of the normal breast tissues. However, no BRCA1 promoter methylation was observed at any site of the normal tissues of the 15 patients with BRCA1-unmethylated tumors. No GSTP1 promoter methylation was observed in the normal tissues regardless of the methylation status of the tumors. The presence of BRCA1 promoter methylation in the normal tissues was confirmed in the epithelial cells enriched with the magnetic-activated cell sorting method. Our findings suggest that a small proportion of normal breast epithelial cells with BRCA1 promoter methylation can be precursor cells from which BRCA1-methylated breast tumors may originate. This does not apply to GSTP1 promoter methylation. PMID:25155055

  18. TP53 suppression promotes erythropoiesis in del(5q) MDS, suggesting a targeted therapeutic strategy in lenalidomide-resistant patients

    Science.gov (United States)

    Caceres, Gisela; McGraw, Kathy; Yip, Bon Ham; Pellagatti, Andrea; Johnson, Joseph; Zhang, Ling; Liu, Kenian; Zhang, Lan Min; Fulp, William J.; Lee, Ji-Hyun; Al Ali, Najla H.; Basiorka, Ashley; Smith, Larry J.; Daugherty, F. Joseph; Littleton, Neil; Wells, Richard A.; Sokol, Lubomir; Wei, Sheng; Komrokji, Rami S.; Boultwood, Jacqueline; List, Alan F.

    2013-01-01

    Stabilization of p53 in erythroid precursors in response to nucleosomal stress underlies the hypoplastic anemia in myelodysplastic syndromes (MDS) with chromosome 5q deletion [del(5q)]. We investigated whether cenersen, a clinically active 20-mer antisense oligonucleotide complementary to TP53 exon10, could suppress p53 expression and restore erythropoiesis in del(5q) MDS. Cenersen treatment of ribosomal protein S-14-deficient erythroblasts significantly reduced cellular p53 and p53-up-regulated modulator of apoptosis expression compared with controls, accompanied by a significant reduction in apoptosis and increased cell proliferation. In a two-stage erythroid differentiation assay, cenersen significantly suppressed nuclear p53 in bone marrow CD34+ cells isolated from patients with del(5q) MDS, whereas erythroid burst recovery increased proportionally to the magnitude of p53 suppression without evidence of del(5q) clonal suppression (r = −0.6; P = 0.005). To explore the effect of p53 suppression on erythropoiesis in vivo, dexamethasone, a glucocorticoid receptor-dependent p53 antagonist, was added to lenalidomide treatment in eight lower-risk, transfusion-dependent, del(5q) MDS patients with acquired drug resistance. Transfusion independence was restored in five patients accompanied by expansion of erythroid precursors and decreased cellular p53 expression. We conclude that targeted suppression of p53 could support effective erythropoiesis in lenalidomide-resistant del(5q) MDS. PMID:24043769

  19. Frequent mutations in EGFR, KRAS and TP53 genes in human lung cancer tumors detected by ion torrent DNA sequencing.

    Directory of Open Access Journals (Sweden)

    Xin Cai

    Full Text Available Lung cancer is the most common malignancy and the leading cause of cancer deaths worldwide. While smoking is by far the leading cause of lung cancer, other environmental and genetic factors influence the development and progression of the cancer. Since unique mutations patterns have been observed in individual cancer samples, identification and characterization of the distinctive lung cancer molecular profile is essential for developing more effective, tailored therapies. Until recently, personalized DNA sequencing to identify genetic mutations in cancer was impractical and expensive. The recent technological advancements in next-generation DNA sequencing, such as the semiconductor-based Ion Torrent sequencing platform, has made DNA sequencing cost and time effective with more reliable results. Using the Ion Torrent Ampliseq Cancer Panel, we sequenced 737 loci from 45 cancer-related genes to identify genetic mutations in 76 human lung cancer samples. The sequencing analysis revealed missense mutations in KRAS, EGFR, and TP53 genes in the breast cancer samples of various histologic types. Thus, this study demonstrates the necessity of sequencing individual human cancers in order to develop personalized drugs or combination therapies to effectively target individual, breast cancer-specific mutations.

  20. PIK3CA and TP53 gene mutations in human breast cancer tumors frequently detected by ion torrent DNA sequencing.

    Science.gov (United States)

    Bai, Xusheng; Zhang, Enke; Ye, Hua; Nandakumar, Vijayalakshmi; Wang, Zhuo; Chen, Lihong; Tang, Chuanning; Li, Jianhui; Li, Huijin; Zhang, Wei; Han, Wei; Lou, Feng; Zhang, Dandan; Sun, Hong; Dong, Haichao; Zhang, Guangchun; Liu, Zhiyuan; Dong, Zhishou; Guo, Baishuai; Yan, He; Yan, Chaowei; Wang, Lu; Su, Ziyi; Li, Yangyang; Jones, Lindsey; Huang, Xue F; Chen, Si-Yi; Gao, Jinglong

    2014-01-01

    Breast cancer is the most common malignancy and the leading cause of cancer deaths in women worldwide. While specific genetic mutations have been linked to 5-10% of breast cancer cases, other environmental and epigenetic factors influence the development and progression of the cancer. Since unique mutations patterns have been observed in individual cancer samples, identification and characterization of the distinctive breast cancer molecular profile is needed to develop more effective target therapies. Until recently, identifying genetic cancer mutations via personalized DNA sequencing was impractical and expensive. The recent technological advancements in next-generation DNA sequencing, such as the semiconductor-based Ion Torrent sequencing platform, has made DNA sequencing cost and time effective with more reliable results. Using the Ion Torrent Ampliseq Cancer Panel, we sequenced 737 loci from 45 cancer-related genes to identify genetic mutations in 105 human breast cancer samples. The sequencing analysis revealed missense mutations in PIK3CA, and TP53 genes in the breast cancer samples of various histologic types. Thus, this study demonstrates the necessity of sequencing individual human cancers in order to develop personalized drugs or combination therapies to effectively target individual, breast cancer-specific mutations.

  1. Frequent mutations in EGFR, KRAS and TP53 genes in human lung cancer tumors detected by ion torrent DNA sequencing.

    Science.gov (United States)

    Cai, Xin; Sheng, Jianhui; Tang, Chuanning; Nandakumar, Vijayalakshmi; Ye, Hua; Ji, Hong; Tang, Haiying; Qin, Yu; Guan, Hongwei; Lou, Feng; Zhang, Dandan; Sun, Hong; Dong, Haichao; Zhang, Guangchun; Liu, Zhiyuan; Dong, Zhishou; Guo, Baishuai; Yan, He; Yan, Chaowei; Wang, Lu; Su, Ziyi; Li, Yangyang; Jones, Lindsey; Huang, Xue F; Chen, Si-Yi; Wu, Taihua; Lin, Hongli

    2014-01-01

    Lung cancer is the most common malignancy and the leading cause of cancer deaths worldwide. While smoking is by far the leading cause of lung cancer, other environmental and genetic factors influence the development and progression of the cancer. Since unique mutations patterns have been observed in individual cancer samples, identification and characterization of the distinctive lung cancer molecular profile is essential for developing more effective, tailored therapies. Until recently, personalized DNA sequencing to identify genetic mutations in cancer was impractical and expensive. The recent technological advancements in next-generation DNA sequencing, such as the semiconductor-based Ion Torrent sequencing platform, has made DNA sequencing cost and time effective with more reliable results. Using the Ion Torrent Ampliseq Cancer Panel, we sequenced 737 loci from 45 cancer-related genes to identify genetic mutations in 76 human lung cancer samples. The sequencing analysis revealed missense mutations in KRAS, EGFR, and TP53 genes in the breast cancer samples of various histologic types. Thus, this study demonstrates the necessity of sequencing individual human cancers in order to develop personalized drugs or combination therapies to effectively target individual, breast cancer-specific mutations.

  2. A common Greenlandic Inuit BRCA1 RING domain founder mutation

    DEFF Research Database (Denmark)

    Hansen, Thomas; Ejlertsen, Bent; Albrechtsen, Anders

    2009-01-01

    exon 3 nucleotide 234 T > G mutation, which has not previously been reported in the breast cancer information core (BIC) database. The mutation changes a conserved cysteine 39 to a glycine in the Zn(2+) site II of the RING domain, which is essential for BRCA1 ubiquitin ligase activity. Eight......Germ-line mutations in the tumour suppressor proteins BRCA1 and BRCA2 predispose to breast and ovarian cancer. We examined 32 breast and/or ovarian cancer patients from Greenland for mutations in BRCA1 and BRCA2. Whereas no mutations were identified in 19 families, 13 families exhibited a BRCA1...... of the families had members with ovarian cancer, suggesting that the RING domain may be an ovarian cancer hotspot. By SNP array analysis, we find that all 13 families share a 4.5 Mb genomic fragment containing the BRCA1 gene, showing that the mutation originates from a founder. Finally, analysis of 1152 Inuit...

  3. Analysis list: BRCA1 [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available BRCA1 Blood,Breast,Digestive tract,Liver,Pluripotent stem cell,Uterus + hg19 http://dbarc...hive.biosciencedbc.jp/kyushu-u/hg19/target/BRCA1.1.tsv http://dbarchive.biosciencedbc.jp/kyushu-u/hg19/target/BRC...A1.5.tsv http://dbarchive.biosciencedbc.jp/kyushu-u/hg19/target/BRCA1.10.tsv http://dbarchive.bio...sciencedbc.jp/kyushu-u/hg19/colo/BRCA1.Blood.tsv,http://dbarchive.biosciencedbc.jp/kyushu-u/hg19/colo/BRC...A1.Breast.tsv,http://dbarchive.biosciencedbc.jp/kyushu-u/hg19/colo/BRCA1.Digestive_tract.tsv,http://dbarc

  4. A common Greenlandic Inuit BRCA1 RING domain founder mutation

    DEFF Research Database (Denmark)

    Hansen, T.v.O.; Ejlertsen, B.; Albrechtsen, Anders

    2009-01-01

    Germ-line mutations in the tumour suppressor proteins BRCA1 and BRCA2 predispose to breast and ovarian cancer. We examined 32 breast and/or ovarian cancer patients from Greenland for mutations in BRCA1 and BRCA2. Whereas no mutations were identified in 19 families, 13 families exhibited a BRCA1...... exon 3 nucleotide 234 T > G mutation, which has not previously been reported in the breast cancer information core (BIC) database. The mutation changes a conserved cysteine 39 to a glycine in the Zn(2+) site II of the RING domain, which is essential for BRCA1 ubiquitin ligase activity. Eight...... of the families had members with ovarian cancer, suggesting that the RING domain may be an ovarian cancer hotspot. By SNP array analysis, we find that all 13 families share a 4.5 Mb genomic fragment containing the BRCA1 gene, showing that the mutation originates from a founder. Finally, analysis of 1152 Inuit...

  5. BRCA1 regulation on β-hCG: a mechanism for tumorigenicity in BRCA1 defective breast cancer.

    Science.gov (United States)

    Sengodan, S K; Nadhan, R; Nair, R S; Hemalatha, S K; Somasundaram, V; Sushama, R R; Rajan, A; Latha, N R; Varghese, G R; Thankappan, R K; Kumar, J M; Chil, A; Anilkumar, T V; Srinivas, P

    2017-09-04

    Human chorionic gonadotropin β (β-hCG) has been implicated in breast tumorigenesis. However, the role of this hormone is highly controversial as certain studies suggest it has anti-tumor properties while others have found it to be pro-tumorigenic. To unveil the truth, we have analyzed the expression of β-hCG in breast cancer. We identified for the first time that β-hCG expression is linked to BRCA1 status and its overexpression is seen in BRCA1 mutated breast cancer cells, BRCA1 conditional knockout mouse breast cancer tissues and BRCA1 floxed basal cell carcinoma (BCC) tissues. An analysis of three large, transcriptomic data sets from TCGA (The Cancer Genome Atlas) expression profile confirmed the inverse correlation between BRCA1 and β-hCG in human breast cancer. Using ChIP and luciferase assays, we also demonstrated that the cancer cells with wild-type but not mutant BRCA1 directly repress the expression of β-hCG by binding to its promoter. Further, β-hCG promotes migration and invasion predominantly in BRCA1 mutant breast cancer cells. Interestingly, stable overexpression of β-hCG in BRCA1 mutant but not wild-type breast cancer cells results in the formation of spheres even on monolayer cultures. The cells of these spheres show high expression of both EMT and stem cell markers. Since β-hCG belongs to a cysteine knot family of proteins like TGFβ and TGFβ signaling is deregulated in BRCA1 defective tumors, we checked whether β-hCG can mediate signaling through TGFβRII in BRCA1 mutated cells. We found for the first time that β-hCG can bind and phosphorylate TGFβRII, irrespective of LHCGR status and induce proliferation in BRCA1 defective cells. Our results confirmed that there exists a transcriptional regulation of BRCA1 on β-hCG and BRCA1 mutation promotes β-hCG mediated tumorigenesis through TGFβRII signaling. Thus inhibiting β-hCG-TGFβRII could prove an effective treatment strategy for BRCA1 mutated tumors.

  6. TP53-induced glycolysis and apoptosis regulator protects from spontaneous apoptosis and predicts poor prognosis in chronic lymphocytic leukemia.

    Science.gov (United States)

    Hong, Ming; Xia, Yi; Zhu, Yu; Zhao, Hui-Hui; Zhu, Han; Xie, Yue; Fan, Lei; Wang, Li; Miao, Kou-Rong; Yu, Hui; Miao, Yu-Qing; Wu, Wei; Zhu, Hua-Yuan; Chen, Yao-Yu; Xu, Wei; Qian, Si-Xuan; Li, Jian-Yong

    2016-11-01

    Circulating chronic lymphocytic leukemia (CLL) cells appear not to be overly utilizing aerobic glycolysis. However, recurrent contact with CLL cells in a stromal microenvironment leads to increased aerobic glycolysis and the cells' overall glycolytic capacity, which promotes cell survival and proliferation. TP53-induced glycolysis and apoptosis regulator (TIGAR) has been directly implicated in cellular metabolism in the control of glycolysis. TIGAR inhibits glycolysis and protects cells from intracellular reactive oxygen species (ROS)-associated apoptosis. TIGAR mRNA expression was investigated by quantitative PCR in 102 newly diagnosed CLL patients. Furthermore, the relationship between the expression of TIGAR and its clinical characteristics and prognosis were investigated. Moreover, we also investigated the correlation between TIGAR expression and apoptosis in primary CLL cells. Our data revealed that TIGAR overexpression was correlated with the protection from spontaneous apoptosis in CLL cells, and is strongly associated with advanced Binet stage, unmutated immunoglobulin heavy-chain variable region (IGHV) status, CD38 positivity, β2-microglobulin and p53 aberrations. Higher expression of TIGAR was associated with shorter treatment-free survival (median: three months vs. 51 months, P=0.0108), worse overall survival (median: 74 months vs. not reached, P=0.0242), and the diverse responses to fludarabine-based chemotherapy. TIGAR expression in patients resistant to chemotherapy was significantly higher than in patients sensitive to chemotherapy (mean: 0.3859±0.1710 vs. 0.0974±0.0291, P=0.0290). Taken together, our findings revealed that high TIGAR expression is closely correlated with worse clinical outcome in CLL patients, and depicted how bioenergetic characteristics could be therapeutically exploited in CLL. Copyright © 2016 Elsevier Ltd. All rights reserved.

  7. TP53-inducible Glycolysis and Apoptosis Regulator (TIGAR) Metabolically Reprograms Carcinoma and Stromal Cells in Breast Cancer.

    Science.gov (United States)

    Ko, Ying-Hui; Domingo-Vidal, Marina; Roche, Megan; Lin, Zhao; Whitaker-Menezes, Diana; Seifert, Erin; Capparelli, Claudia; Tuluc, Madalina; Birbe, Ruth C; Tassone, Patrick; Curry, Joseph M; Navarro-Sabaté, Àurea; Manzano, Anna; Bartrons, Ramon; Caro, Jaime; Martinez-Outschoorn, Ubaldo

    2016-12-16

    A subgroup of breast cancers has several metabolic compartments. The mechanisms by which metabolic compartmentalization develop in tumors are poorly characterized. TP53 inducible glycolysis and apoptosis regulator (TIGAR) is a bisphosphatase that reduces glycolysis and is highly expressed in carcinoma cells in the majority of human breast cancers. Hence we set out to determine the effects of TIGAR expression on breast carcinoma and fibroblast glycolytic phenotype and tumor growth. The overexpression of this bisphosphatase in carcinoma cells induces expression of enzymes and transporters involved in the catabolism of lactate and glutamine. Carcinoma cells overexpressing TIGAR have higher oxygen consumption rates and ATP levels when exposed to glutamine, lactate, or the combination of glutamine and lactate. Coculture of TIGAR overexpressing carcinoma cells and fibroblasts compared with control cocultures induce more pronounced glycolytic differences between carcinoma and fibroblast cells. Carcinoma cells overexpressing TIGAR have reduced glucose uptake and lactate production. Conversely, fibroblasts in coculture with TIGAR overexpressing carcinoma cells induce HIF (hypoxia-inducible factor) activation with increased glucose uptake, increased 6-phosphofructo-2-kinase/fructose-2,6-bisphosphatase-3 (PFKFB3), and lactate dehydrogenase-A expression. We also studied the effect of this enzyme on tumor growth. TIGAR overexpression in carcinoma cells increases tumor growth in vivo with increased proliferation rates. However, a catalytically inactive variant of TIGAR did not induce tumor growth. Therefore, TIGAR expression in breast carcinoma cells promotes metabolic compartmentalization and tumor growth with a mitochondrial metabolic phenotype with lactate and glutamine catabolism. Targeting TIGAR warrants consideration as a potential therapy for breast cancer. © 2016 by The American Society for Biochemistry and Molecular Biology, Inc.

  8. BRCA1/BARD1 ubiquitinate phosphorylated RNA polymerase II.

    Science.gov (United States)

    Starita, Lea M; Horwitz, Andrew A; Keogh, Michael-Christopher; Ishioka, Chikashi; Parvin, Jeffrey D; Chiba, Natsuko

    2005-07-01

    The breast- and ovarian-specific tumor suppressor BRCA1, when associated with BARD1, is an ubiquitin ligase. We have shown here that this heterodimer ubiquitinates a hyperphosphorylated form of Rpb1, the largest subunit of RNA polymerase II. Two major phosphorylation sites have been identified in the Rpb1 carboxyl terminal domain, serine 2 (Ser-2) or serine 5 (Ser-5) of the YSPTSPS heptapeptide repeat. Only the Ser-5 hyperphosphorylated form is ubiquitinated by BRCA1/BARD1. Overexpression of BRCA1 in cells stimulated the DNA damage-induced ubiquitination of Rpb1. Similar to the in vitro reaction, the stimulation of Rpb1 ubiquitination by BRCA1 in cells occurred only on those molecules hyperphosphorylated on Ser-5 of the heptapeptide repeat. In vitro, the carboxyl terminus of BRCA1 (amino acids 501-1863) was dispensable for the ubiquitination of hyperphosphorylated Rpb1. In cells, however, efficient Rpb1 ubiquitination required the carboxyl terminus of BRCA1, suggesting that interactions mediated by this region were essential in the complex milieu of the nucleus. These results link the BRCA1-dependent ubiquitination of the polymerase with DNA damage.

  9. Common variants of the BRCA1 wild-type allele modify the risk of breast cancer in BRCA1 mutation carriers

    DEFF Research Database (Denmark)

    Cox, David G; Simard, Jacques; Sinnett, Daniel

    2011-01-01

    Mutations in the BRCA1 gene substantially increase a woman's lifetime risk of breast cancer. However, there is great variation in this increase in risk with several genetic and non-genetic modifiers identified. The BRCA1 protein plays a central role in DNA repair, a mechanism that is particularly...... instrumental in safeguarding cells against tumorigenesis. We hypothesized that polymorphisms that alter the expression and/or function of BRCA1 carried on the wild-type (non-mutated) copy of the BRCA1 gene would modify the risk of breast cancer in carriers of BRCA1 mutations. A total of 9874 BRCA1 mutation...... carriers were available in the Consortium of Investigators of Modifiers of BRCA1/2 (CIMBA) for haplotype analyses of BRCA1. Women carrying the rare allele of single nucleotide polymorphism rs16942 on the wild-type copy of BRCA1 were at decreased risk of breast cancer (hazard ratio 0.86, 95% confidence...

  10. Major prognostic value of complex karyotype in addition to TP53 and IGHV mutational status in first-line chronic lymphocytic leukemia.

    Science.gov (United States)

    Le Bris, Yannick; Struski, Stéphanie; Guièze, Romain; Rouvellat, Caroline; Prade, Naïs; Troussard, Xavier; Tournilhac, Olivier; Béné, Marie C; Delabesse, Eric; Ysebaert, Loïc

    2017-12-01

    Chronic lymphocytic leukemia (CLL) is a lymphoproliferative disorder of remarkable heterogeneity as demonstrated by cytogenetics and molecular analyses. Complex karyotype (CK), TP53 deletions and/or mutations (TP53 disruption), IGVH mutational status, and, more recently, recurrent somatic mutations have been identified as prognostic markers in CLL. On a cohort of 110 patients with CLL treated with first-line fludarabin, cyclophosphamide, and rituximab treatment compared with 33 untreated (watch and wait) patients with CLL, we report more frequent complex karyotypes (34 vs 15%; P = .05), unmutated IGHV (70 vs 21%; P karyotyping therefore appears to be of value, CK being an additional factor, undetectable in classical FISH, in patients with CLL at the stage when therapy becomes required. Copyright © 2016 John Wiley & Sons, Ltd.

  11. Investigation of single-strand conformational polymorphism of the TP53 gene in women with a family history of breast cancer

    Directory of Open Access Journals (Sweden)

    R.R. Burbano

    2000-11-01

    Full Text Available Breast cancer in families with germ line mutations in the TP53 gene has been described in the medical literature. Mutation screening for susceptibility genes should allow effective prophylactic and preventive measures. Using single-strand conformational polymorphism, we screened for mutations in exons 5, 6, 7 and 8 of gene TP53 in the peripheral blood of 8 young non-affected members (17 to 36 years old of families with a history of breast cancer. Studies of this type on young patients (mean age, 25 years are very rare in the literature. The identification of these mutations would contribute to genetic counseling of members of families with predisposition to breast cancer. The results obtained did not show any polymorphism indicating mutation. In our sample, the familial tumorigenesis is probably related to other gene etiologies.

  12. Blockade of extracellular NM23 or its endothelial target slows breast cancer growth and metastasis.

    Science.gov (United States)

    Yokdang, Nucharee; Nordmeier, Senny; Speirs, Katie; Burkin, Heather R; Buxton, Iain L O

    Nucleoside Diphosphate Kinase (NDPK), described as NM23 a metastasis suppressor, is found in the culture medium of cancer cells lines suggesting that the kinase may have an extracellular role. We propose that extracellular NM23 released from breast cancers in vivo stimulates tumor cell migration, proliferation and endothelial cell angiogenesis in support of metastasis development. NM23 in the bloodstream of immunocompromised mice carrying human triple-negative breast cancers or in breast cancer patients was measured by ELISA. Primary and metastatic tumor development, the impact of blockade of NM23 and/or its stimulation of nucleotide receptors were measured using in vivo imaging. NM23 expression data in the Curtis breast dataset was examined to test our hypothesis that NM23 may play a mechanistic role in breast cancer development. SCID mice carrying metastatic MDA-MB-231Luc+ triple-negative human breast tumor cells elaborate NM23 into the circulation correlated with primary tumor growth. Treatment of mice with the NM23 inhibitor ellagic acid (EA) or the purinergic receptor antagonist MRS2179 slowed primary tumor growth. At 16 weeks following implantation, lung metastases were reduced in mice treated with EA, MRS2179 or the combination. Expression of NM23 in the Curtis breast dataset confirmed a likely role for NM23 in tumor metastasis. Extracellular NM23 may constitute both a biomarker and a therapeutic target in the management of breast cancer.

  13. A novel TP53 splicing mutation in a Li-Fraumeni syndrome family: a patient with Wilms' tumour is not a mutation carrier.

    OpenAIRE

    Varley, J. M.; McGown, G; Thorncroft, M.; White, G. R.; Tricker, K. J.; Kelsey, A M; Birch, J M; Evans, D. G.

    1998-01-01

    We report a Li-Fraumeni syndrome family in which we have detected a splice acceptor mutation in intron 3 of TP53. The mutation affects one of the invariant residues at the splice acceptor site, as a result of which two aberrant transcripts are produced. A child with Wilms' tumour aged 3 years in this family was shown not to be a mutation carrier.

  14. A novel TP53 splicing mutation in a Li-Fraumeni syndrome family: a patient with Wilms' tumour is not a mutation carrier.

    Science.gov (United States)

    Varley, J. M.; McGown, G.; Thorncroft, M.; White, G. R.; Tricker, K. J.; Kelsey, A. M.; Birch, J. M.; Evans, D. G.

    1998-01-01

    We report a Li-Fraumeni syndrome family in which we have detected a splice acceptor mutation in intron 3 of TP53. The mutation affects one of the invariant residues at the splice acceptor site, as a result of which two aberrant transcripts are produced. A child with Wilms' tumour aged 3 years in this family was shown not to be a mutation carrier. PMID:9792154

  15. Influence of TP53 and CDH1 genes in hepatocellular cancer spheroid formation and culture: a model system to understand cancer cell growth mechanics.

    Science.gov (United States)

    Pomo, Joseph M; Taylor, Robert M; Gullapalli, Rama R

    2016-01-01

    Spheroid based culture methods are gaining prominence to elucidate the role of the microenvironment in liver carcinogenesis. Additionally, the phenomenon of epithelial-mesenchymal transition also plays an important role in determining the metastatic potential of liver cancer. Tumor spheroids are thus important models to understand the basic biology of liver cancer. We cultured, characterized and examined the formation of compact 3-D micro-tumor spheroids in five hepatocellular carcinoma (HCC) cell lines, each with differing TP53 mutational status (wt vs mutant vs null). Spheroid viability and death was systematically measured over a course of a 10 day growth period using various assays. We also examined the TP53 and E-cadherin (CDH1) mRNA and protein expression status in each cell line of the 2-D and 3-D cell models. A novel finding of our study was the identification of variable 3-D spheroid morphology in individual cell lines, ranging from large and compact, to small and unstable spheroid morphologies. The observed morphological differences between the spheroids were robust and consistent over the duration of spheroid culture growth of 10 days in a repeatable manner. Highly variable CDH1 expression was identified depending on the TP53 mutational status of the individual HCC cell line, which may explain the variable spheroid morphology. We observed consistent patterns of TP53 and CDH1 expression in both 2-D and 3-D culture models. In conclusion, we show that 3-D spheroids are a useful model to determine the morphological growth characteristics of cell lines which are not immediately apparent in routine 2-D culture methods. 3-D culture methods may provide a better alternative to study the process of epithelial-mesenchymal transition (EMT) which is important in the process of liver cancer metastasis.

  16. Adrenocortical carcinoma with extension to the inferior vena cava and right atrium: 20-month-old girl with TP53 mutation

    Directory of Open Access Journals (Sweden)

    Terry L. Levin, MD

    2015-01-01

    Full Text Available A 20-month-old female presented with respiratory distress and a right adrenal mass extending into the inferior vena cava and right atrium. The mass was initially thought to be neuroblastoma. Pathology later revealed adrenocortical carcinoma. Inferior vena cava extension is far more common in adrenocortical carcinoma than neuroblastoma, and its presence should prompt clinical and laboratory evaluation for an adrenocortical tumor. The genetic findings in TP53 associated with this disease are discussed.

  17. Whole-exome analysis of a Li-Fraumeni family trio with a novel TP53 PRD mutation and anticipation profile.

    Science.gov (United States)

    Franceschi, Sara; Spugnesi, Laura; Aretini, Paolo; Lessi, Francesca; Scarpitta, Rosa; Galli, Alvaro; Congregati, Caterina; Caligo, Maria Adelaide; Mazzanti, Chiara Maria

    2017-09-01

    Li-Fraumeni syndrome is a clinically heterogeneous familial cancer predisposition syndrome with autosomal-dominant inheritance caused by heterozygous germline mutations in the TP53 gene. We here analyze the genetic background of a family with a 4-year-proband presented with a Li-Fraumeni tumor. The mother developed breast cancer at age 37 and the proband died at age 8. We performed Sanger sequencing and whole-exome sequencing on peripheral blood DNA from proband and relatives. Data analysis selected only high-quality score and depth reads, rare variants and protein impact involving missense, non-sense, frameshift and splice disrupt mutations. Disease implicated variants and predicted deleterious alterations were also chosen. TP53 genetic testing revealed a never reported TP53 deletion arose as de novo mutation in the mother and inherited by the proband. We then performed whole-exome analysis of the trio to uncover inherited variants from the father that potentially worsen the already altered genetic background in the proband. No pathogenic variants were inherited in autosomal recessive, de novo dominant or X-linked recessive manner. Comparing proband and father exome we detected 25 predicted deleterious variants including a nonsense mutation in ERCC3. Those inherited mutations are possible candidate modifiers linked to TP53, explaining the proband accelerated tumor onset compared to the mother and providing a possible explanation of the genetic anticipation event in this Li-Fraumeni family. © The Author 2017. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  18. Acetaldehyde-induced mutational pattern in the tumour suppressor gene TP53 analysed by use of a functional assay, the FASAY (functional analysis of separated alleles in yeast).

    Science.gov (United States)

    Paget, Vincent; Lechevrel, Mathilde; Sichel, Francois

    2008-03-29

    Chronic alcohol consumption is a major risk factor for upper aero-digestive tract cancers, including cancer of the esophagus. Whereas alcohol as such is not thought to be directly carcinogenic, acetaldehyde, its first metabolite, has been proven genotoxic and mutagenic in the HPRT gene. As mutations in the tumour suppressor gene TP53 are the most common genetic alterations involved in human cancers, especially esophageal tumours, the aim of this work was to establish the mutational pattern induced by acetaldehyde in vitro on the TP53 gene, and to compare this pattern with that found in human alcohol-related tumours. For this purpose, we used a functional assay in yeast, the FASAY (functional analysis of separated alleles in yeast), after in vitro exposure of human normal fibroblasts AG1521 to acetaldehyde. We noted 35 mutations, of which 32 were single-nucleotide substitutions including 2 nonsense and 30 missense mutations. The pattern showed that the main mutations were G>A transitions (n=23, of which 14 in CpG sites), followed by G>T transversions (n=4), A>G transitions (n=2) and A>T transversions (n=2). Other mutations were one-base insertion and two deletions, leading to frameshifts. Eleven mutations (31%) were located in TP53 hot-spots in codons 245, 248, 249 and 273. Finally, we compared this pattern with that found for esophageal cancers in humans. These results support the notion that acetaldehyde plays a role in TP53 mutations in esophageal cancers. The key feature of this approach is that mutagenesis is directly studied in a key gene in human carcinogenesis, allowing direct comparison of mutational patterns with those in human tumours.

  19. Function of BRCA1 at a DNA Replication Origin

    National Research Council Canada - National Science Library

    Lieberman, Paul

    2004-01-01

    ... and allow efficient repair of damaged DNA. In this proposal, we present preliminary data that BRCA1 functions in a DNA checkpoint response for the origin of Epstein-Barr Virus DNA replication (Ori P...

  20. Structural Basis for BRCA1 Function in Breast Cancer

    National Research Council Canada - National Science Library

    Ladias, John A

    2005-01-01

    The Breast Cancer Susceptibility gene 1 (BRCA1) encodes an 1863-amino acid protein that has important functions in cell cycle checkpoint control and DNA repair and plays a central role in the pathogenesis of breast cancer...

  1. Diffuse large B-cell lymphoma with combined TP53 mutation and MIR34A methylation

    DEFF Research Database (Denmark)

    Asmar, Fazila; Hother, Christoffer; Kulosman, Gorjan

    2014-01-01

    MiR34A, B and C have been implicated in lymphomagenesis, but information on their role in normal CD19+ B-cells (PBL-B) and de novo diffuse large B-cell lymphoma (DLBCL) is limited. We show that in normal and activated B-cells miR34A-5p plays a dominant role compared to other miR34 family members....... Only miR34A-5p is expressed in PBL-B, and significantly induced in activated B-cells and reactive lymph nodes. In PBL-B, the MIR34A and MIR34B/C promoters are unmethylated, but the latter shows enrichment for the H3K4me3/H3K27me3 silencing mark. Nine de novo DLBCL cases (n=150) carry both TP53 mutation...... negative prognostic factor for survival (P=0.0002). In 2 DLBCL-cell lines with both TP53 mutation and promoter methylation of MIR34A, miR34A-5p is upregulated by 5-aza-2'deoxycytidine. Thus, the TP53/MIR34A "double hit" characterizes a very aggressive subgroup of DLBCL, which may be treatable...

  2. Novel small molecule XPO1/CRM1 inhibitors induce nuclear accumulation of TP53, phosphorylated MAPK and apoptosis in human melanoma cells.

    Directory of Open Access Journals (Sweden)

    Jennifer Yang

    Full Text Available XPO1/CRM1 is a key nuclear exporter protein that mediates translocation of numerous cellular regulatory proteins. We investigated whether XPO1 is a potential therapeutic target in melanoma using novel selective inhibitors of nuclear export (SINE. In vitro effects of SINE on cell growth and apoptosis were measured by MTS assay and flow cytometry [Annexin V/propidium iodide (PI], respectively in human metastatic melanoma cell lines. Immunoblot analysis was used to measure nuclear localization of key cellular proteins. The in vivo activity of oral SINE was evaluated in NOD/SCID mice bearing A375 or CHL-1 human melanoma xenografts. SINE compounds induced cytostatic and pro-apoptotic effects in both BRAF wild type and mutant (V600E cell lines at nanomolar concentrations. The cytostatic and pro-apoptotic effects of XPO1 inhibition were associated with nuclear accumulation of TP53, and CDKN1A induction in the A375 cell line with wild type TP53, while pMAPK accumulated in the nucleus regardless of TP53 status. The orally bioavailable KPT-276 and KPT-330 compounds significantly inhibited growth of A375 (p<0.0001 and CHL-1 (p = 0.0087 human melanoma cell lines in vivo at well tolerated doses. Inhibition of XPO1 using SINE represents a potential therapeutic approach for melanoma across cells with diverse molecular phenotypes by promoting growth inhibition and apoptosis.

  3. Association of the type of 5q loss with complex karyotype, clonal evolution, TP53 mutation status, and prognosis in acute myeloid leukemia and myelodysplastic syndrome.

    Science.gov (United States)

    Volkert, Sarah; Kohlmann, Alexander; Schnittger, Susanne; Kern, Wolfgang; Haferlach, Torsten; Haferlach, Claudia

    2014-05-01

    We analyzed 1,200 patients with acute myeloid leukemia (AML) and myelodysplastic syndrome (MDS) harboring a 5q deletion in order to clarify whether the type of 5q loss is associated with other biological markers and prognosis. We investigated all patients by chromosome banding analysis, FISH with a probe for EGR1 (5q31) and, if necessary, to resolve complex karyotypes with 24-color-FISH. Moreover, 420 patients were analyzed for mutations in the TP53 gene. The patient cohort was subdivided based on type of 5q loss: Patients with interstitial deletions and patients with 5q loss due to unbalanced rearrangements or monosomy 5. Loss of the long arm of chromosome 5 due to an unbalanced rearrangement occurred more often in AML (286/627; 45.6%) than MDS (188/573; 32.8%; P evolution (109/188; 58.0% vs. 124/385; 32.2%; P HR = 5.34; P = 0.032), whereas in AML presence of TP53 mutations was the strongest adverse prognostic factor (HR = 2.21; P = 0.026). In conclusion, in AML and MDS, loss of the long arm of chromosome 5 due to unbalanced translocations is associated with complex karyotype and in MDS, moreover, with clonal evolution, mutations in the TP53 gene and adverse prognosis. Copyright © 2014 Wiley Periodicals, Inc.

  4. Multiple genetic copy number alterations in oral squamous cell carcinoma: study of MYC, TP53, CCDN1, EGFR and ERBB2 status in primary and metastatic tumours.

    Science.gov (United States)

    Martín-Ezquerra, G; Salgado, R; Toll, A; Gilaberte, M; Baró, T; Alameda Quitllet, F; Yébenes, M; Solé, F; Garcia-Muret, M; Espinet, B; Pujol, R M

    2010-11-01

    Oncogenesis in the oral cavity is believed to result from genetic alterations that cause a stepwise transformation of the mucosa to invasive carcinoma. In oral squamous cell carcinoma (OSCC) multiple cytogenetic abnormalities have been reported, but their practical significance remains uncertain. To evaluate the usefulness of the assessment of CCND1, MYC, EGFR, ERBB2 and TP53 in OSCC and lymph node metastases. Fifty-one consecutive samples of OSCC, nine lymph node biopsies showing metastatic spread from OSCC, 16 biopsies diagnosed as oral leucoplakia (OLK), 13 samples corresponding to oral lichen planus (OLP) and 14 samples from normal oral mucosa were included in the study. Clinical and histopathological characteristics were reviewed. The genetic and protein status of the CCND1, MYC, EGFR, ERBB2 oncogenes and the TP53 tumour suppressor gene were assessed by fluorescence in situ hybridization (FISH) and immunohistochemistry (IHC). The obtained results were compared with the clinical characteristics and the outcome of the OSCCs. TP53 gene losses and MYC, ERBB2, CCND1 and EGFR copy number gains and amplifications were detected in a higher proportion in OSCC and lymph node samples than in OLK and OLP samples (P oral lesions in histopathologically challenging cases. © 2010 The Authors. BJD © 2010 British Association of Dermatologists.

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

    Science.gov (United States)

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

    2015-03-21

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

  6. Novel cancerization marker, TP53, and its role in distinguishing normal tissue adjacent to cancerous tissue from normal tissue adjacent to benign tissue

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    Liu Guo-Yan

    2012-11-01

    Full Text Available Abstract Background The histopathological and molecular heterogeneity of normal tissue adjacent to cancerous tissue (NTAC and normal tissue adjacent to benign tissue (NTAB, and the availability of limited specimens make deciphering the mechanisms of carcinogenesis challenging. Our goal was to identify histogenetic biomarkers that could be reliably used to define a transforming fingerprint using RNA in situ hybridization. Methods We evaluated 15 tumor-related RNA in situ hybridization biomarkers using tumor microarray and samples of seven tumor-adjacent normal tissues from 314 patients. Biomarkers were determined using comprehensive statistical methods (significance of support vector machine-based artificial intelligence and area under curve scoring of classification distribution. Results TP53 was found to be a most reliable index (P -7; area under curve >87% for distinguishing NTAC from NTAB, according to the results of a significance panel (BCL10, BECN1, BRCA2, FITH, PTCH11 and TP53. Conclusions The genetic alterations in TP53 between NTAC and NTAB may provide new insight into the field of cancerization and tumor transformation.

  7. Novel cancerization marker, TP53, and its role in distinguishing normal tissue adjacent to cancerous tissue from normal tissue adjacent to benign tissue

    Science.gov (United States)

    2012-01-01

    Background The histopathological and molecular heterogeneity of normal tissue adjacent to cancerous tissue (NTAC) and normal tissue adjacent to benign tissue (NTAB), and the availability of limited specimens make deciphering the mechanisms of carcinogenesis challenging. Our goal was to identify histogenetic biomarkers that could be reliably used to define a transforming fingerprint using RNA in situ hybridization. Methods We evaluated 15 tumor-related RNA in situ hybridization biomarkers using tumor microarray and samples of seven tumor-adjacent normal tissues from 314 patients. Biomarkers were determined using comprehensive statistical methods (significance of support vector machine-based artificial intelligence and area under curve scoring of classification distribution). Results TP53 was found to be a most reliable index (P 87%) for distinguishing NTAC from NTAB, according to the results of a significance panel (BCL10, BECN1, BRCA2, FITH, PTCH11 and TP53). Conclusions The genetic alterations in TP53 between NTAC and NTAB may provide new insight into the field of cancerization and tumor transformation. PMID:23170979

  8. Identification of a novel germ-line mutation in the TP53 gene in a Mexican family with Li-Fraumeni syndrome.

    Science.gov (United States)

    Taja-Chayeb, Lucia; Vidal-Millán, Silvia; Gutiérrez-Hernández, Olga; Trejo-Becerril, Catalina; Pérez-Cárdenas, Enrique; Chávez-Blanco, Alma; de la Cruz-Hernández, Erick; Dueñas-González, Alfonso

    2009-12-17

    Germ-line mutations of the TP53 gene are known to cause Li-Fraumeni syndrome, an autosomal, dominantly inherited, high-penetrance cancer-predisposition syndrome characterized by the occurrence of a variety of cancers, mainly soft tissue sarcomas, adrenocortical carcinoma, leukemia, breast cancer, and brain tumors. Mutation analysis was based on Denaturing high performance liquid chromatography (DHPLC) screening of exons 2-11 of the TP53 gene, sequencing, and cloning of DNA obtained from peripheral blood lymphocytes. We report herein on Li Fraumeni syndrome in a family whose members are carriers of a novel TP53 gene mutation at exon 4. The mutation comprises an insertion/duplication of seven nucleotides affecting codon 110 and generating a new nucleotide sequence and a premature stop codon at position 150. With this mutation, the p53 protein that should be translated lacks the majority of the DNA binding domain. To our knowledge, this specific alteration has not been reported previously, but we believe it is the cause of the Li-Fraumeni syndrome in this family.

  9. Identification of a novel germ-line mutation in the TP53 gene in a Mexican family with Li-Fraumeni syndrome

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    de la Cruz-Hernández Erick

    2009-12-01

    Full Text Available Abstract Background Germ-line mutations of the TP53 gene are known to cause Li-Fraumeni syndrome, an autosomal, dominantly inherited, high-penetrance cancer-predisposition syndrome characterized by the occurrence of a variety of cancers, mainly soft tissue sarcomas, adrenocortical carcinoma, leukemia, breast cancer, and brain tumors. Methods Mutation analysis was based on Denaturing high performance liquid chromatography (DHPLC screening of exons 2-11 of the TP53 gene, sequencing, and cloning of DNA obtained from peripheral blood lymphocytes. Results We report herein on Li Fraumeni syndrome in a family whose members are carriers of a novel TP53 gene mutation at exon 4. The mutation comprises an insertion/duplication of seven nucleotides affecting codon 110 and generating a new nucleotide sequence and a premature stop codon at position 150. With this mutation, the p53 protein that should be translated lacks the majority of the DNA binding domain. Conclusion To our knowledge, this specific alteration has not been reported previously, but we believe it is the cause of the Li-Fraumeni syndrome in this family.

  10. The TP53 mutational spectrum and frequency of CHEK2*1100delC in Li-Fraumeni-like kindreds.

    Science.gov (United States)

    Siddiqui, Rina; Onel, Kenan; Facio, Flavia; Nafa, Kedoudja; Diaz, Louis Robles; Kauff, Noah; Huang, Helen; Robson, Mark; Ellis, Nathan; Offit, Kenneth

    2005-01-01

    Li-Fraumeni syndrome (LFS) is a dominantly inherited cancer predisposition syndrome characterized by a wide spectrum of neoplasms occurring at young age. Germline mutations in the TP53 tumor suppressor gene have been identified in approximately 71 of LFS patients and 22 of Li-Fraumeni-like (LFL) patients. Mutations within the cell cycle checkpoint gene CHEK2 have also been reported in some patients with LFS, LFL, and phenotypically suggestive of LFS (PS-LFS) not carrying a TP53 mutation. In this study, we show that 7 of the 23 patients with LFS/LFL tested positive for deleterious mutations in p53. Fifteen of the remaining sixteen were not found to carry the CHEK2* 1100delCmutation. These results indicate that CHEK2*1100delC is not a common cause of LFS, LFL, or PS-LFS in North American kindreds not carrying a TP53 mutation. Of note, two patients were found to carry p53* R72P, which is of unknown clinical significance. Lack of segregation of this allele in one of these kindreds provides strong evidence that the R72P allele is not disease-causing. While mutations in p53 account for a proportion of patients with LFS/LFL, future studies are needed to determine if other genes are responsible for LFS/LFL families not carrying germline p53 mutations.

  11. [Description of a new TP53 gene germline mutation in a family with the Li-Fraumeni syndrome. Genetic counselling to healthy mutation carriers].

    Science.gov (United States)

    Balmaña, Judith; Nomdedéu, Josep; Díez, Orland; Sabaté, Josep Maria; Balil, Anna; Pericay, Carles; López López, Juan José; Brunet, Joan; Baiget, Montse; Alonso, Carmen

    2002-10-19

    Li-Fraumeni syndrome is a dominantly inherited disorder characterized by early-onset breast cancer, soft-tissue sarcomas and osteosarcomas, acute leukemia, adrenocortical neoplasms and central nervous system tumors. Germline mutations in gene TP53 are identified in a percentage of affected families. Eight families with aggregation of childhood sarcomas, brain tumors, breast cancers in pre-menopausal women, and renal tumors were screened for TP53 germ-line mutations. SSCP and posterior direct sequencing were performed for genetic analysis. We also report a previously undescribed family with the Li-Fraumeni syndrome carrying a germline mutation. Seven families fulfilled so-called Li-Fraumeni like criteria and one fulfilled classical criteria. A new germ-line mutation in codon 238 at exon 7 of the gene TP53 was identified in the family fulfilling classical criteria. This mutation has not been previously reported. The clinical heterogeneity as well as the molecular complexity and consequences of mutation analysis and genetic counseling make it necessary to develop protocols in this area. A multidisciplinary approach is needed; this approach should be coordinated by a Familial Cancer Genetic Counseling Unit.

  12. Further evidence for pathogenicity of the TP53 tetramerization domain mutation p.Arg342Pro in Li-Fraumeni syndrome.

    Science.gov (United States)

    Etzold, Anna; Schröder, Julia C; Bartsch, Oliver; Zechner, Ulrich; Galetzka, Danuta

    2015-03-01

    Li-Fraumeni syndrome (LFS) is a rare genetic disease with a highly significant predisposition to multiple early-onset neoplasms. These neoplasms include adrenocortical carcinoma, sarcoma, leukemia and CNS tumors in children and sarcoma, breast cancer and lung cancer in adults. LFS is inherited in an autosomal dominant manner. In most patients germline mutations in the tumor suppressor gene TP53 are found. As the majority of known mutations affect the DNA-binding domain of the p53 protein, there are only a few case reports showing the clinical presentation of mutations outside of this mutational hotspot. Here we present a family with a typical LFS pedigree with patients suffering from early-onset lung cancer, bilateral breast cancer and osteosarcoma. TP53 sequence analysis of the index patient revealed the germline mutation c.1025G > C in a heterozygous state, resulting in an amino acid exchange from arginine to proline (p.Arg342Pro) in the tetramerization domain of p53. Using DNA from an old bedside blood typing test, the same mutation was found in the mother of the index patient, who had died of breast cancer 29 years ago. In conclusion, we provide evidence for the co-segregation of a TP53 tetramerization domain mutation and cancer phenotypes, but also report pre-symptomatic mutation carriers within the family. We review published recommendations for clinical management and surveillance of high-risk members in Li-Fraumeni kindreds.

  13. Ovarian carcinomas with genetic and epigenetic BRCA1 loss have distinct molecular abnormalities

    Energy Technology Data Exchange (ETDEWEB)

    Gilks, C. Blake; Press, Joshua Z.; De Luca, Alessandro; Boyd, Niki; Young, Sean; Troussard, Armelle; Ridge, Yolanda; Kaurah, Pardeep; Kalloger, Steve E.; Blood, Katherine A.; Smith, Margaret; Spellman, Paul T.; Wang, Yuker; Miller, Dianne M.; Horsman, Doug; Faham, Malek; Gilks, C. Blake; Gray, Joe; Huntsman, David G.

    2008-05-02

    Subclassification of ovarian carcinomas can be used to guide treatment and determine prognosis. Germline and somatic mutations, loss of heterozygosity (LOH), and epigenetic events such as promoter hypermethylation can lead to decreased expression of BRCA1/2 in ovarian cancers. The mechanism of BRCA1/2 loss is a potential method of subclassifying high grade serous carcinomas. A consecutive series of 49 ovarian cancers was assessed for mutations status of BRCA1 and BRCA2, LOH at the BRCA1 and BRCA2 loci, methylation of the BRCA1 promoter, BRCA1, BRCA2, PTEN, and PIK3CA transcript levels, PIK3CA gene copy number, and BRCA1, p21, p53, and WT-1 immunohistochemistry. Eighteen (37%) of the ovarian carcinomas had germline or somatic BRCA1 mutations, or epigenetic loss of BRCA1. All of these tumors were high-grade serous or undifferentiated type. None of the endometrioid (n=5), clear cell (n=4), or low grade serous (n=2) carcinomas showed loss of BRCA1, whereas 47% of the 38 high-grade serous or undifferentiated carcinomas had loss of BRCA1. It was possible to distinguish high grade serous carcinomas with BRCA1 mutations from those with epigenetic BRCA1 loss: tumors with BRCA1 mutations typically had decreased PTEN mRNA levels while those with epigenetic loss of BRCA1 had copy number gain of PIK3CA. Overexpression of p53 with loss of p21 expression occurred significantly more frequently in high grade serous carcinomas with epigenetic loss of BRCA1, compared to high grade serous tumors without loss of BRCA1. High grade serous carcinomas can be subclassified into three groups: BRCA1 loss (genetic), BRCA1 loss (epigenetic), and no BRCA1 loss. Tumors in these groups show distinct molecular alterations involving the PI3K/AKT and p53 pathways.

  14. Ovarian carcinomas with genetic and epigenetic BRCA1 loss havedistinct molecular abnormalities

    Energy Technology Data Exchange (ETDEWEB)

    Press, Joshua Z.; De Luca, Alessandro; Boyd, Niki; Young, Sean; Troussard, Armelle; Ridge, Yolanda; Kaurah, Pardeep; Kalloger, Steve E.; Blood, Katherine A.; Smith, Margaret; Spellman, Paul T.; Wang, Yuker; Miller, Dianne M.; Horsman, Doug; Faham, Malek; Gilks, C. Blake; Gray,Joe; Huntsman, David G.

    2007-07-23

    Subclassification of ovarian carcinomas can be used to guide treatment and determine prognosis. Germline and somatic mutations, loss of heterozygosity (LOH), and epigenetic events such as promoter hypermethylation can lead to decreased expression of BRCA1/2 in ovarian cancers. The mechanism of BRCA1/2 loss is a potential method of subclassifying high grade serous carcinomas. A consecutive series of 49 ovarian cancers was assessed for mutations status of BRCA1 and BRCA2, LOH at the BRCA1 and BRCA2 loci, methylation of the BRCA1 promoter, BRCA1, BRCA2, PTEN, and PIK3CA transcript levels, PIK3CA gene copy number, and BRCA1, p21, p53, and WT-1 immunohistochemistry. Eighteen (37%) of the ovarian carcinomas had germline or somatic BRCA1 mutations, or epigenetic loss of BRCA1. All of these tumors were high-grade serous or undifferentiated type. None of the endometrioid (n = 5), clear cell (n = 4), or low grade serous (n = 2) carcinomas showed loss of BRCA1, whereas 47% of the 38 high-grade serous or undifferentiated carcinomas had loss of BRCA1. It was possible to distinguish high grade serous carcinomas with BRCA1 mutations from those with epigenetic BRCA1 loss: tumors with BRCA1 mutations typically had decreased PTEN mRNA levels while those with epigenetic loss of BRCA1 had copy number gain of PIK3CA. Overexpression of p53 with loss of p21 expression occurred significantly more frequently in high grade serous carcinomas with epigenetic loss of BRCA1, compared to high grade serous tumors without loss of BRCA1. High grade serous carcinomas can be subclassified into three groups: BRCA1 loss (genetic), BRCA1 loss (epigenetic), and no BRCA1 loss. Tumors in these groups show distinct molecular alterations involving the PI3K/AKT and p53 pathways.

  15. The performance of BRCA1 immunohistochemistry for detecting germline, somatic, and epigenetic BRCA1 loss in high-grade serous ovarian cancer.

    Science.gov (United States)

    Meisel, J L; Hyman, D M; Garg, K; Zhou, Q; Dao, F; Bisogna, M; Gao, J; Schultz, N D; Grisham, R N; Phillips, M; Iasonos, A; Kauff, N D; Levine, D A; Soslow, R A; Spriggs, D R

    2014-12-01

    BRCA1 expression can be lost by a variety of mechanisms including germline or somatic mutation and promotor hypermethylation. Given the potential importance of BRCA1 loss as a predictive and prognostic biomarker in high-grade serous ovarian cancer, we sought to evaluate the utility of BRCA1 immunohistochemistry (IHC) in screening for BRCA1 loss by germline, somatic, and epigenetic mechanisms. Patients with advanced high-grade serous ovarian cancer who had previously undergone germline BRCA1 testing were identified. Samples from each tumor were stained for BRCA1 and reviewed independently by two pathologists blinded to BRCA status. Tumors with abnormal BRCA1 IHC and wild-type germline testing underwent further evaluation for somatic BRCA1 mutations and promoter hypermethylation. McNemar's test was used to determine the association of BRCA1 IHC with germline BRCA1 mutations and BRCA1 loss through any mechanism. Kaplan-Meier methods were used to estimate overall survival (OS), and the log-rank test was used to assess differences between groups. Inter-rater reliability between the two pathologists on BRCA IHC interpretation was very good (kappa coefficient 0.865, P = 0.16; McNemar's test). BRCA1 IHC was abnormal in 36% (48/135) of cases. When compared with germline BRCA1 status, BRCA1 IHC had a high negative predictive value (95.4%) but a low positive predictive value (PPV, 52.1%). When accounting for promoter hypermethylation and somatic mutations as alternative methods of BRCA1 loss, the PPV rose to 87.5%. Five-year OS rate was 49.6% [95% confidence interval (CI) 26.3% to 69.3%] for patients with germline BRCA1 mutations, 50.4% (95% CI 27.5% to 69.5%) for germline wild-type BRCA1 and abnormal IHC, and 52.1% (95% CI 38.4% to 64.2%) for germline wild-type BRCA1 and normal IHC (P = 0.92). BRCA1 IHC interpretation was a highly reproducible and accurate modality for detecting germline, somatic, or epigenetic mechanisms of BRCA1 loss. These results support further

  16. BRCA1 Mutation: A Predictive Marker for Radiation Therapy?

    Energy Technology Data Exchange (ETDEWEB)

    Kan, Charlene; Zhang, Junran, E-mail: Junran.zhang@case.edu

    2015-10-01

    DNA repair, in particular, DNA double-strand break (DSB) repair, is essential for the survival of both normal and cancer cells. An elaborate repair mechanism has been developed in cells to efficiently repair the damaged DNA. The pathways predominately involved in DSB repair are homologous recombination and classic nonhomologous end-joining, although the alternative NHEJ pathway, a third DSB repair pathway, could also be important in certain contexts. The protein of BRCA1 encoded by the tumor suppressor gene BRCA1 regulates all DSB repair pathways. Given that DSBs represent the most biologically significant lesions induced by ionizing radiation and that impaired DSB repair leads to radiation sensitivity, it has been expected that cancer patients with BRCA1 mutations should benefit from radiation therapy. However, the clinical data have been conflicting and inconclusive. We provide an overview about the current status of the data regarding BRCA1 deficiency and radiation therapy sensitivity in both experimental models and clinical investigations. In addition, we discuss a strategy to potentiate the effects of radiation therapy by poly(ADP-ribose) polymerase inhibitors, the pharmacologic drugs being investigated as monotherapy for the treatment of patients with BRCA1/2 mutations.

  17. The Presence of Telomere Fusion in Sporadic Colon Cancer Independently of Disease Stage, TP53/KRAS Mutation Status, Mean Telomere Length, and Telomerase Activity

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    Hiromi Tanaka

    2014-10-01

    Full Text Available Defects in telomere maintenance can result in telomere fusions that likely play a causative role in carcinogenesis by promoting genomic instability. However, this proposition remains to be fully understood in human colon carcinogenesis. In the present study, the temporal sequence of telomere dysfunction dynamics was delineated by analyzing telomere fusion, telomere length, telomerase activity, hotspot mutations in KRAS or BRAF, and TP53 of tissue samples obtained from 18 colon cancer patients. Our results revealed that both the deficiency of p53 and the shortening of mean telomere length were not necessary for producing telomere fusions in colon tissue. In five cases, telomere fusion was observed even in tissue adjacent to cancerous lesions, suggesting that genomic instability is initiated in pathologically non-cancerous lesions. The extent of mean telomere attrition increased with lymph node invasiveness of tumors, implying that mean telomere shortening correlates with colon cancer progression. Telomerase activity was relatively higher in most cancer tissues containing mutation(s in KRAS or BRAF and/or TP53 compared to those without these hotspot mutations, suggesting that telomerase could become fully active at the late stage of colon cancer development. Interestingly, the majority of telomere fusion junctions in colon cancer appeared to be a chromatid-type containing chromosome 7q or 12q. In sum, this meticulous correlative study not only highlights the concept that telomere fusion is present in the early stages of cancer regardless of TP53/KRAS mutation status, mean telomere length, and telomerase activity, but also provides additional insights targeting key telomere fusion junctions which may have significant implications for colon cancer diagnoses.

  18. EZH2-mediated repression of GSK-3β and TP53 promotes Wnt/β-catenin signaling-dependent cell expansion in cervical carcinoma

    Science.gov (United States)

    Chen, Qian; Zheng, Peng-Sheng; Yang, Wen-Ting

    2016-01-01

    Enhancer of zeste homolog 2 (EZH2), a catalytic core component of the Polycomb repressive complex 2 (PRC2), stimulates the silencing of target genes through histone H3 lysine 27 trimethylation (H3K27me3). Recent findings have indicated EZH2 is involved in the development and progression of various human cancers. However, the exact mechanism of EZH2 in the promotion of cervical cancer is largely unknown. Here, we show that EZH2 expression gradually increases during the progression of cervical cancer. We identified a significant positive correlation between EZH2 expression and cell proliferation in vitro and tumor formation in vivo by the up-regulation or down-regulation of EZH2 using CRISPR-Cas9-mediated gene editing technology and shRNA in HeLa and SiHa cells. Further investigation indicated that EZH2 protein significantly accelerated the cell cycle transition from the G0/G1 to S phase. TOP/FOP-Flash reporter assay revealed that EZH2 significantly activated Wnt/β-catenin signaling and the target genes of Wnt/β-catenin pathway were up-regulated, including β-catenin, cyclin D1, and c-myc. Moreover, dual-luciferase reporter and chromatin immunoprecipitation (ChIP) assays confirmed that EZH2 inhibited the expression of glycogen synthase kinase-3β (GSK-3β) and TP53 through physically interacting with motifs in the promoters of the GSK-3β and TP53 genes. Additionally, blockage of the Wnt/β-catenin pathway resulted in significant inhibition of cell proliferation, and activation of the Wnt/β-catenin pathway resulted in significant enhancement of cell proliferation, as induced by EZH2. Taken together, our data demonstrate that EZH2 promotes cell proliferation and tumor formation in cervical cancer through activating the Wnt/β-catenin pathway by epigenetic silencing via GSK-3β and TP53. PMID:27092879

  19. Association of the highly prevalent TP53 R337H mutation with pediatric choroid plexus carcinoma and osteosarcoma in southeast Brazil.

    Science.gov (United States)

    Seidinger, Ana Luiza; Mastellaro, Maria José; Paschoal Fortes, Fernanda; Godoy Assumpção, Juliana; Aparecida Cardinalli, Izilda; Aparecida Ganazza, Mônica; Correa Ribeiro, Raul; Brandalise, Silvia Regina; Dos Santos Aguiar, Simone; Yunes, José Andrés

    2011-05-15

    The inherited, low-penetrance arginine-to-histidine substitution at codon 337 (R337H) of the tumor protein 53 gene (TP53) is clustered in southeast Brazil (estimated frequency, 0.3%). Although its tumorigenic effect initially appeared to be tissue-specific, recent evidence suggests its association with a broader range of tumors. Therefore, the authors of this report investigated the spectrum of pediatric malignancies associated with the TP53 R337H mutation at a single referral institution in southeast Brazil. Genomic DNA samples from 493 children with malignancies were screened for the R337H mutation. Available tumor samples from carriers were investigated for loss of heterozygosity (LOH) and nuclear p53 accumulation. Clinical data were obtained from medical records. Sixty-five of 70 patients (93%) with adrenocortical tumors (ACTs), 9 of 13 patients (69%) with choroid plexus carcinoma (CPC), and 3 of 41 patients (7.3%) with osteosarcoma carried the mutation. The proportion of CPC to choroid plexus papilloma (CPP) was much higher than that reported elsewhere. Osteosarcoma in carriers had a significantly poorer outcome (P = .02). The mutation was not identified in patients who had acute lymphoblastic leukemia (ALL) (n = 187), recurrent ALL (n = 49), acute myeloid leukemia (n = 44), lymphoma (n = 30), non-CPC central nervous system tumors (n = 26), Ewing sarcoma (n = 25), or rhabdomyosarcoma (n = 8). Among the tumors that were available for analysis, LOH with retention of the mutant allele was confirmed in 21 of 21 ACTs, in 2 of 2 CPCs, and in 2 of 3 osteosarcomas that were positive for R337H. CPCs and osteosarcomas that were positive for R337H had marked nuclear accumulation of p53. The current findings demonstrated compellingly that the TP53 R337H mutation is associated not only with ACT but also with CPC and, to a lesser extent, with osteosarcoma, both of which are core-component tumors of the Li-Fraumeni syndrome. 2010 American Cancer Society.

  20. TP53 mutations, human papilloma virus DNA and inflammation markers in esophageal squamous cell carcinoma from the Rift Valley, a high-incidence area in Kenya

    Directory of Open Access Journals (Sweden)

    Martel-Planche Ghislaine

    2011-10-01

    Full Text Available Abstract Background Squamous Cell Carcinoma of Esophagus is one of the most common malignancies in both men and women in eastern and south-eastern Africa. In Kenya, clinical observations suggest that this cancer is frequent in the Rift Valley area. However, so far, there has been no report on the molecular characteristics of esophageal squamous cell carcinoma (ESCC in this area. Results We have analyzed TP53 mutations, the presence of human papilloma virus (HPV DNA and expression of inflammation markers Cyclooxygenase 2 (Cox-2 and Nitrotyrosine (NTyR in 28 cases (13 males and 15 females of archived ESCC tissues collected at the Moi Teaching and Referral Hospital in Eldoret, Kenya. Eleven mutations were detected in TP53 exons 5 to 8 (39%. All ESCC samples were negative for HPV 16, 18, 26, 31, 33, 35, 39, 45, 51, 52, 53, 56, 58, 59, 66, 68, 70, 73 and 82. Immunohistochemical analysis of Cox-2 and NTyR showed a low proportion of positive cases (17.4% and 39.1%, respectively. No association between the above markers and suspected risk factors (alcohol or tobacco use, hot tea drinking, use of charcoal for cooking was found. Conclusion Our findings suggest that mechanisms of esophageal carcinogenesis in eastern Africa might be different from other parts of the world. Low prevalence of TP53 mutation compared with other intermediate or high incidence areas of the world highlights this hypothesis. Our data did not support a possible ole of HPV in this series of cases. Further studies are needed to assess and compare the molecular patterns of ESCC from Kenya with those of high-incidence areas such as China or Central Asia.

  1. EZH2-mediated repression of GSK-3β and TP53 promotes Wnt/β-catenin signaling-dependent cell expansion in cervical carcinoma.

    Science.gov (United States)

    Chen, Qian; Zheng, Peng-Sheng; Yang, Wen-Ting

    2016-06-14

    Enhancer of zeste homolog 2 (EZH2), a catalytic core component of the Polycomb repressive complex 2 (PRC2), stimulates the silencing of target genes through histone H3 lysine 27 trimethylation (H3K27me3). Recent findings have indicated EZH2 is involved in the development and progression of various human cancers. However, the exact mechanism of EZH2 in the promotion of cervical cancer is largely unknown. Here, we show that EZH2 expression gradually increases during the progression of cervical cancer. We identified a significant positive correlation between EZH2 expression and cell proliferation in vitro and tumor formation in vivo by the up-regulation or down-regulation of EZH2 using CRISPR-Cas9-mediated gene editing technology and shRNA in HeLa and SiHa cells. Further investigation indicated that EZH2 protein significantly accelerated the cell cycle transition from the G0/G1 to S phase. TOP/FOP-Flash reporter assay revealed that EZH2 significantly activated Wnt/β-catenin signaling and the target genes of Wnt/β-catenin pathway were up-regulated, including β-catenin, cyclin D1, and c-myc. Moreover, dual-luciferase reporter and chromatin immunoprecipitation (ChIP) assays confirmed that EZH2 inhibited the expression of glycogen synthase kinase-3β (GSK-3β) and TP53 through physically interacting with motifs in the promoters of the GSK-3β and TP53 genes. Additionally, blockage of the Wnt/β-catenin pathway resulted in significant inhibition of cell proliferation, and activation of the Wnt/β-catenin pathway resulted in significant enhancement of cell proliferation, as induced by EZH2. Taken together, our data demonstrate that EZH2 promotes cell proliferation and tumor formation in cervical cancer through activating the Wnt/β-catenin pathway by epigenetic silencing via GSK-3β and TP53.

  2. BRCA1 interaction of centrosomal protein Nlp is required for successful mitotic progression.

    Science.gov (United States)

    Jin, Shunqian; Gao, Hua; Mazzacurati, Lucia; Wang, Yang; Fan, Wenhong; Chen, Qiang; Yu, Wei; Wang, Mingrong; Zhu, Xueliang; Zhang, Chuanmao; Zhan, Qimin

    2009-08-21

    Breast cancer susceptibility gene BRCA1 is implicated in the control of mitotic progression, although the underlying mechanism(s) remains to be further defined. Deficiency of BRCA1 function leads to disrupted mitotic machinery and genomic instability. Here, we show that BRCA1 physically interacts and colocalizes with Nlp, an important molecule involved in centrosome maturation and spindle formation. Interestingly, Nlp centrosomal localization and its protein stability are regulated by normal cellular BRCA1 function because cells containing BRCA1 mutations or silenced for endogenous BRCA1 exhibit disrupted Nlp colocalization to centrosomes and enhanced Nlp degradation. Its is likely that the BRCA1 regulation of Nlp stability involves Plk1 suppression. Inhibition of endogenous Nlp via the small interfering RNA approach results in aberrant spindle formation, aborted chromosomal segregation, and aneuploidy, which mimic the phenotypes of disrupted BRCA1. Thus, BRCA1 interaction of Nlp might be required for the successful mitotic progression, and abnormalities of Nlp lead to genomic instability.

  3. Análisis genético en APC, KRAS y TP53 en pacientes con cáncer de estómago y colon

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    K.A. Palacio-Rúa

    2014-04-01

    Conclusión: Las mutaciones en los genes APC, KRAS y TP53 fueron más comunes en el CCR que en el CE; nuestros resultados indican la existencia de diferentes vías genéticas en la carcinogénesis del CE y del CCR, y revelan una frecuencia de mutaciones particular en los pacientes colombianos estudiados, que podría estar influida por factores ambientales y étnicos, y el estilo de vida de esta población.

  4. Massively Parallel Functional Analysis of BRCA1 RING Domain Variants.

    Science.gov (United States)

    Starita, Lea M; Young, David L; Islam, Muhtadi; Kitzman, Jacob O; Gullingsrud, Justin; Hause, Ronald J; Fowler, Douglas M; Parvin, Jeffrey D; Shendure, Jay; Fields, Stanley

    2015-06-01

    Interpreting variants of uncertain significance (VUS) is a central challenge in medical genetics. One approach is to experimentally measure the functional consequences of VUS, but to date this approach has been post hoc and low throughput. Here we use massively parallel assays to measure the effects of nearly 2000 missense substitutions in the RING domain of BRCA1 on its E3 ubiquitin ligase activity and its binding to the BARD1 RING domain. From the resulting scores, we generate a model to predict the capacities of full-length BRCA1 variants to support homology-directed DNA repair, the essential role of BRCA1 in tumor suppression, and show that it outperforms widely used biological-effect prediction algorithms. We envision that massively parallel functional assays may facilitate the prospective interpretation of variants observed in clinical sequencing. Copyright © 2015 by the Genetics Society of America.

  5. The coding region of TP53INP2, a gene expressed in the developing nervous system, is not altered in a family with autosomal recessive non-progressive infantile ataxia on chromosome 20q11-q13.

    Science.gov (United States)

    Bennetts, Jennifer S; Rendtorff, Nanna D; Simpson, Fiona; Tranebjaerg, Lisbeth; Wicking, Carol

    2007-03-01

    The locus for autosomal recessive infantile cerebellar ataxia (CLA3 or SCAR6) has been mapped to chromosome 20q11-q13 in a single Norwegian pedigree. We identified a relatively uncharacterised mouse gene Tp53inp2, and showed that its human orthologue mapped within this candidate interval. Tp53inp2 appears to encode a mammalian-specific protein with homology to the two Tp53inp1 isoforms that respond to cellular stress and interact with p53. We show that Tp53inp2 expression is highly restricted during mouse embryogenesis, with strong expression in the developing brain and spinal cord, as well as in the sensory and motor neuron tracts of the peripheral nervous system. Given this expression pattern, the neurological phenotype of CLA3 and the chromosomal localisation of TP53INP2, we searched the coding region for mutations in samples from individuals from the CLA3 pedigree. Our failure to detect causative mutations suggests that alterations in the coding region of TP53INP2 are not responsible for ataxia in this family, although we cannot rule out changes in non-coding elements of this gene.

  6. LOS GENES BRCA1 y BRCA2. ESTUDIO MOLECULAR

    OpenAIRE

    N. Alonso; R. García Iglesias; L. Martín Rodríguez; J.A. Minguéz Pargas; I. Gonzalez Blanco; A. San Miguel; F.J. Martín Gil

    2006-01-01

    RESUMENEn los últimos años, se realizaron numerosos estudios para establecer la predisposición hereditaria al cáncer y las alteraciones mutacionales a nivel de genes susceptibles de originar cáncer de mama y ovario. En 1994 se identificaron los genes BRCA1 (Breast Cancer Gene 1) y BRCA2 (Breast Cancer Gene 2) como susceptibles de cáncer de mama y ovario. En la actualidad se sabe que las mutaciones en BRCA1 y BRCA2 están lejos de explicar la totalidad de los casos de cáncer de mama y/o ovario,...

  7. nm23-H1 expression in non-Hodgkin and Hodgkin lymphomas.

    Science.gov (United States)

    Bircan, Sema; Inamdar, Kedar V; Rassidakis, George Z; Medeiros, L J

    2008-05-01

    We assessed for nm23-H1 expression in 262 lymphoid neoplasms including 191 B-cell non-Hodgkin lymphoma (NHL), 54 T-cell NHL, and 17 Hodgkin lymphoma (HL). We used a monoclonal anti-nm23-H1 antibody, routinely processed tissue, and immunohistochemical methods. We semiquantified the percentage of positive cells (0%, 75%) and also estimated staining intensity (1 to 3+). Some percentage of nm23-H1 positive cells was detected in almost all types of NHL and HL, but T-cell NHL (87%) and HL (94.1%) more frequently had >75% positive cells than B-cell NHL (47.6%) (T- NHL vs. B-NHL, Ptypes of NHL and HL the nm23-H1 immunoreactivity was predominantly cytoplasmic. However, in plasma cell myeloma (PCM) nm23-H1 immunoreactivity was predominantly nuclear. In B-cell NHL, the percentage of nm23-H1-positive cells and the intensity of staining was not significantly different between various lymphoma types with the exception of PCM. We conclude that nm23-H1 is expressed in most types of B-cell and T-cell NHLs and HL, with a greater number of positive cells and higher staining intensity in T-cell NHL and HL, and PCM often being negative. The abundant intracellular expression of nm23-H1 suggests that serum levels of nm23-H1 are a reflection of tumor content. Unlike the conclusions of earlier studies, nm23-H1 expression in B-cell NHL was not significantly increased in clinically aggressive versus indolent neoplasms.

  8. Robust BRCA1-like classification of copy number profiles of samples repeated across different datasets and platforms

    NARCIS (Netherlands)

    Schouten, Philip C.; Grigoriadis, Anita; Kuilman, Thomas; Mirza, Hasan; Watkins, Johnathan A.; Cooke, Saskia A.; van Dyk, Ewald; Severson, Tesa M.; Rueda, Oscar M.; Hoogstraat, Marlous; Verhagen, Caroline V. M.; Natrajan, Rachael; Chin, Suet-Feung; Lips, Esther H.; Kruizinga, Janneke; Velds, Arno; Nieuwland, Marja; Kerkhoven, Ron M.; Krijgsman, Oscar; Vens, Conchita; Peeper, Daniel; Nederlof, Petra M.; Caldas, Carlos; Tutt, Andrew N.; Wessels, Lodewyk F.; Linn, Sabine C.

    Breast cancers with BRCA1 germline mutation have a characteristic DNA copy number (CN) pattern. We developed a test that assigns CN profiles to be 'BRCA1-like' or 'non-BRCA1-like', which refers to resembling a BRCA1-mutated tumor or resembling a tumor without a BRCA1 mutation, respectively.

  9. DNA impedance biosensor for detection of cancer, TP53 gene mutation, based on gold nanoparticles/aligned carbon nanotubes modified electrode.

    Science.gov (United States)

    Fayazfar, H; Afshar, A; Dolati, M; Dolati, A

    2014-07-11

    For the first time, a new platform based on electrochemical growth of Au nanoparticles on aligned multi-walled carbon nanotubes (A-MWCNT) was developed for sensitive lable-free DNA detection of the TP53 gene mutation, one of the most popular genes in cancer research. Electrochemical impedance spectroscopy (EIS) was used to monitor the sequence-specific DNA hybridization events related to TP53 gene. Compared to the bare Ta or MWCNT/Ta electrodes, the synergistic interactions of vertically aligned MWCNT array and gold nanoparticles at modified electrode could improve the density of the probe DNA attachment and resulting the sensitivity of the DNA sensor greatly. Using EIS, over the extended DNA concentration range, the change of charge transfer resistance was found to have a linear relationship in respect to the logarithm of the complementary oligonucleotides sequence concentrations in the wide range of 1.0×10(-15)-1.0×10(-7)M, with a detection limit of 1.0×10(-17)M (S/N=3). The prepared sensor also showed good stability (14 days), reproducibility (RSD=2.1%) and could be conveniently regenerated via dehybridization in hot water. The significant improvement in sensitivity illustrates that combining gold nanoparticles with the on-site fabricated aligned MWCNT array represents a promising platform for achieving sensitive biosensor for fast mutation screening related to most human cancer types. Copyright © 2014. Published by Elsevier B.V.

  10. Methylation of the tumor suppressor protein, BRCA1, influences its transcriptional cofactor function.

    Directory of Open Access Journals (Sweden)

    Irene Guendel

    Full Text Available BACKGROUND: Approximately half of hereditary breast cancers have mutations in either BRCA1 or BRCA2. BRCA1 is a multifaceted tumor suppressor protein that has implications in processes such as cell cycle, transcription, DNA damage response and chromatin remodeling. This multifunctional nature of BRCA1 is achieved by exerting its many effects through modulation of transcription. Many cellular events are dictated by covalent modification of proteins, an important mechanism in regulating protein and genome function; of which protein methylation is an important posttranslational modification with activating or repressive effects. METHODS/PRINCIPAL FINDINGS: Here we demonstrate for the first time that BRCA1 is methylated both in breast cancer cell lines and breast cancer tumor samples at arginine and lysine residues through immunoprecipitation and western blot analysis. Arginine methylation by PRMT1 was observed in vitro and the region of BRCA1 504-802 shown to be highly methylated. PRMT1 was detected in complex with BRCA1 504-802 through in vitro binding assays and co-immunoprecipitated with BRCA1. Inhibition of methylation resulted in decreased BRCA1 methylation and alteration of BRCA1 binding to promoters in vivo as shown through chromatin immunoprecipitation assays. Knockdown of PRMT1 also resulted in increased BRCA1 binding to particular promoters in vivo. Finally, following methylation inhibition, Sp1 was found to preferentially associate with hypo-methylated BRCA1 and STAT1 was found to preferentially associate with hyper-methylated BRCA1. CONCLUSIONS/SIGNIFICANCE: These results suggest that methylation may influence either the ability of BRCA1 to bind to specific promoters or protein-protein interactions which alters the recruitment of BRCA1 to these promoters. Thus, given the importance of BRCA1 to genomic stability, methylation of BRCA1 may ultimately affect the tumor suppressor ability of BRCA1.

  11. Genomic signature of BRCA1 deficiency in sporadic basal-like breast tumors.

    Science.gov (United States)

    Joosse, Simon A; Brandwijk, Kim I M; Mulder, Lennart; Wesseling, Jelle; Hannemann, Juliane; Nederlof, Petra M

    2011-02-01

    About 10-20% of all breast carcinomas show a basal-like phenotype, while ∼ 90% of breast tumors from BRCA1-mutation carriers are of this subtype. There is growing evidence that BRCA1-mutated tumors are not just a specific subset of the basal-like tumors, but that (the majority of) basal-like tumors show a dysfunctional BRCA1 pathway. This has major treatment implications, because emerging regimens specifically targeting DNA repair mechanisms would then be most effective against these tumors. To further understand the involvement of BRCA1 deficiency in sporadic basal-like tumors, we investigated 41 basal-like tumors for BRCA1 mRNA expression by quantitative real-time polymerase chain reaction, BRCA1 promoter methylation, their genomic profile by array-CGH, and gene expression levels by whole genome expression arrays. Array-CGH results were compared to those of 34 proven BRCA1-mutated tumors. Basal-like tumors were subdivided into two equal groups: deficient and proficient in BRCA1 gene expression. The chromosomal makeup of BRCA1 deficient sporadic basal-like tumors was similar to that of BRCA1-mutated tumors. BRCA1 proficient sporadic basal-like tumors were more similar to nonbasal-like tumors. Only half of the basal-like breast tumors are actually deficient in BRCA1 expression. Gain of chromosome arm 3q is a marker for BRCA1 deficiency in hereditary and sporadic breast tumors. © 2010 Wiley-Liss, Inc.

  12. Screening for genomic rearrangements at BRCA1 locus in Iranian ...

    Indian Academy of Sciences (India)

    Home; Journals; Journal of Genetics; Volume 92; Issue 1. Screening for genomic rearrangements at BRCA1 locus in Iranian women with breast cancer using multiplex ligation-dependent probe amplification. Vahid R. Yassaee Babak Emamalizadeh Mir Davood Omrani. Research Note Volume 92 Issue 1 April 2013 pp 131- ...

  13. Identification of novel intronic BRCA1 variants of uncertain ...

    Indian Academy of Sciences (India)

    in a Thai hereditary breast cancer family. Adisorn Ratanaphan, Pornpen Panomwan, Bhutorn Canyuk and Tanaphon Maipang. J. Genet. 90, 327–331. Table 1. Oligodeoxyribonucleotide primers used for PCR amplification of BRCA1 exon–intron 7 boundary sequences. Primers. Nucleotide position. Primer sequence (5 –3 ).

  14. Identification of novel intronic BRCA1 variants of uncertain ...

    Indian Academy of Sciences (India)

    Identification of novel intronic BRCA1 variants of uncertain significance in a Thai hereditary breast cancer family ... Faculty of Pharmaceutical Sciences, Department of Pharmaceutical Chemistry, Laboratory of Pharmaceutical Biotechnology, Prince of Songkla University, Hat-Yai, Songkhla 90112, Thailand; Faculty of ...

  15. "Ring-fencing" BRCA1 tumor suppressor activity.

    Science.gov (United States)

    Patel, Ketan J; Crossan, Gerry P; Hodskinson, Michael R G

    2011-12-13

    BRCA1 is a crucial human breast and ovarian cancer tumor suppressor gene. The article by Drost et al. in this issue of Cancer Cell together with a recent paper in Science now provide a clearer picture of how this large and complex protein suppresses tumorigenesis. Copyright © 2011 Elsevier Inc. All rights reserved.

  16. BRCA1/BRCA2 founder mutations and cancer risks

    DEFF Research Database (Denmark)

    Nielsen, Henriette Roed; Nilbert, Mef; Petersen, Janne

    2016-01-01

    Mutations in the BRCA1 and BRCA2 genes significantly contribute to hereditary breast cancer and ovarian cancer, but the phenotypic effect from different mutations is insufficiently recognized. We used a western Danish clinic-based cohort of 299 BRCA families to study the female cancer risk...... in mutation carriers and their untested first-degree relatives. Founder mutations were characterized and the risk of cancer was assessed in relation to the specific mutations. In BRCA1, the cumulative cancer risk at age 70 was 35 % for breast cancer and 29 % for ovarian cancer. In BRCA2, the cumulative risk...... was 44 % for breast cancer and 15 % for ovarian cancer. We identified 47 distinct BRCA1 mutations and 48 distinct mutations in BRCA2. Among these, 8 founder mutations [BRCA1 c.81-?_4986+?del, c.3319G>T (p.Glu1107*), c.3874delT and c.5213G>A (p.Gly1738Glu) and BRCA2 c.6373delA, c.7008-1G>A, c.7617+1G...

  17. BRCA1 and BRCA2 germline mutation analysis among Indian ...

    Indian Academy of Sciences (India)

    Prakash

    , Gupta V, Shukla N K, Deo S S and Das B C 2004. Novel germline mutations in breast cancer susceptibility genes. BRCA1, BRCA2 and p53 gene in breast cancer patients from. India; Breast Cancer Res. Treat. 88 177–186. Ikeda N, Miyoshi Y, ...

  18. Localization of BRCA1 protein in human breast cancer cells.

    Science.gov (United States)

    Chambon, Monique; Nirdé, Philippe; Gleizes, Michel; Roger, Pascal; Vignon, Françoise

    2003-05-01

    There is still an ongoing debate concerning the cellular localization of BRCA1 protein in breast cancer. To address this question, we compared the localization of BRCA1 protein using several monoclonal (Ab-1) or polyclonal (C20, D20, I20) antibodies under different technical conditions on human breast cancer cell lines. We worked on the fixation and permeabilization conditions in order to preserve the morphological structures of the cells, as confirmed by transmission electron microscopy studies. As expected from the gene sequence analysis and the biochemical features, both nucleus and cytoplasmic BRCA1 protein staining were detected in cells fixed for 60 min in 4% paraformaldehyde and permeabilized with either 0.3% saponin or 0.02% Triton. In these conditions, the same results were obtained: (i) with the four antibodies tested, (ii) with several dilutions (up to tenfold) of the monoclonal antibody, and (iii) in all the tested breast cancer cell lines. In addition, we validated the functionality of these conditions by quantifying the effects of estrogens and their antagonists on the regulation of BRCA1 protein expression in the MCF7 cell line.

  19. The Role of BRCA1/BARD1 Heterodimers in the Mitosis-Interphase Transition

    National Research Council Canada - National Science Library

    Joukov, Vladimir

    2007-01-01

    ... and ovarian tumor suppressor BRCA1 and its hetorodimerizing partner, BARD1. Experiments using both egg extracts and cultured mammalian cells revealed a previously unknown role of BRCA1/BARD1 in the mitotic spindle assembly...

  20. Prognostic impact of BRCA1 pathogenic and BRCA1/BRCA2 unclassified variant mutations in patients with ovarian carcinoma

    NARCIS (Netherlands)

    Majdak, EJ; Debniak, J; Milczek, T; Cornelisse, CJ; Devilee, P; Emerich, J; Jassem, J; De Bock, GH

    2005-01-01

    BACKGROUND. The clinical relevance of BRCA1/2 alterations in ovarian carcinoma patients is debatable. Our aim was to determine factors influencing the risk of recurrence and death in ovarian carcinoma patients with BRCA pathogenic and unclassified variant mutations. METHODS. A consecutive series of

  1. Differential expression of ID4 and its association with TP53 mutation, SOX2, SOX4 and OCT-4 expression levels.

    Directory of Open Access Journals (Sweden)

    Thais Fernanda de Almeida Galatro

    Full Text Available Inhibitor of DNA Binding 4 (ID4 is a member of the helix-loop-helix ID family of transcription factors, mostly present in the central nervous system during embryonic development, that has been associated with TP53 mutation and activation of SOX2. Along with other transcription factors, ID4 has been implicated in the tumorigenic process of astrocytomas, contributing to cell dedifferentiation, proliferation and chemoresistance. In this study, we aimed to characterize the ID4 expression pattern in human diffusely infiltrative astrocytomas of World Health Organization (WHO grades II to IV of malignancy (AGII-AGIV; to correlate its expression level to that of SOX2, SOX4, OCT-4 and NANOG, along with TP53 mutational status; and to correlate the results with the clinical end-point of overall survival among glioblastoma patients. Quantitative real time PCR (qRT-PCR was performed in 130 samples of astrocytomas for relative expression, showing up-regulation of all transcription factors in tumor cases. Positive correlation was found when comparing ID4 relative expression of infiltrative astrocytomas with SOX2 (r = 0.50; p<0.005, SOX4 (r = 0.43; p<0.005 and OCT-4 (r = 0.39; p<0.05. The results from TP53 coding exon analysis allowed comparisons between wild-type and mutated status only in AGII cases, demonstrating significantly higher levels of ID4, SOX2 and SOX4 in mutated cases (p<0.05. This pattern was maintained in secondary GBM and further confirmed by immunohistochemistry, suggesting a role for ID4, SOX2 and SOX4 in early astrocytoma tumorigenesis. Combined hyperexpression of ID4, SOX4 and OCT-4 conferred a much lower (6 months median survival than did hypoexpression (18 months. Because both ID4 alone and a complex of SOX4 and OCT-4 activate SOX2 transcription, it is possible that multiple activation of SOX2 impair the prognosis of GBM patients. These observational results of associated expression of ID4 with SOX4 and OCT-4 may be used as a

  2. Contralateral breast cancer after radiotherapy among BRCA1 and BRCA2 mutation carriers

    DEFF Research Database (Denmark)

    Bernstein, Jonine L; Thomas, Duncan C; Shore, Roy E

    2013-01-01

    Women with germline BRCA1 or BRCA2 (BRCA1/BRCA2) mutations are at very high risk of developing breast cancer, including asynchronous contralateral breast cancer (CBC). BRCA1/BRCA2 genes help maintain genome stability and assist in DNA repair. We examined whether the risk of CBC associated with ra...

  3. Expression of the stem cell marker ALDH1 in BRCA1 related breast cancer

    NARCIS (Netherlands)

    Heerma van Voss, Marise R.; van der Groep, Petra; Bart, Joost; van der Wall, Elsken; van Diest, Paul J.

    Introduction The BRCA1 protein makes mammary stem cells differentiate into mature luminal and myoepithelial cells. If a BRCA1 mutation results in a differentiation block, an enlarged stem cell component might be present in the benign tissue of BRCA1 mutation carriers, and these mammary stem cells

  4. Comparative synchronous fluorescence spectrophotometry and 32P-postlabeling analysis of PAH-DNA adducts in human lung and the relationship to TP53 mutations

    DEFF Research Database (Denmark)

    Andreassen, Åshild; Kure, Elin H.; Nielsen, Per Sabro

    1996-01-01

    Polycyclic aromatic hydrocarbon (PAH)-DNA adducts were studied in human lung from 39 lung cancer patients by synchronous fluorescence spectrophotometric (SFS) and 32P-postlabeling assays. Regression analysis of the samples failed to detect any correlation between benzo[a]pyrene-diolepoxide (BPDE......)-DNA adducts detected by SFS and the BPDE co-migrating spot detected by 32P-postlabeling. We have also analyzed the relationship between adduct levels and TP53 mutations. By postlabeling diagonal radioactive zone (DRZ) adducts were detected in 37 of 39 (95%) lung tissues from lung cancer patients...... and the adduct level ranged from 6.81 to 108.50 adducts/10(8) nucleotide. Thirty-three of 39 (85%) had detectable levels of BPDE-DNA adducts (> 1 adduct/10(9) nucleotide). Current heavy smokers (> 20 cigarettes/day) have significantly higher DRZ adduct levels compared to individuals smoking less than 20...

  5. CCND2, CTNNB1, DDX3X, GLI2, SMARCA4, MYC, MYCN, PTCH1, TP53, and MLL2 gene variants and risk of childhood medulloblastoma.

    Science.gov (United States)

    Dahlin, Anna M; Hollegaard, Mads V; Wibom, Carl; Andersson, Ulrika; Hougaard, David M; Deltour, Isabelle; Hjalmars, Ulf; Melin, Beatrice

    2015-10-01

    Recent studies have described a number of genes that are frequently altered in medulloblastoma tumors and that have putative key roles in the development of the disease. We hypothesized that common germline genetic variations in these genes may be associated with medulloblastoma development. Based on recent publications, we selected 10 genes that were frequently altered in medulloblastoma: CCND2, CTNNB1, DDX3X, GLI2, SMARCA4, MYC, MYCN, PTCH1, TP53, and MLL2 (now renamed as KMT2D). Common genetic variants (single nucleotide polymorphisms) annotating these genes (n = 221) were genotyped in germline DNA (neonatal dried blood spot samples) from 243 childhood medulloblastoma cases and 247 control subjects from Sweden and Denmark. Eight genetic variants annotating three genes in the sonic hedgehog signaling pathway; CCND2, PTCH1, and GLI2, were found to be associated with the risk of medulloblastoma (P(combined) medulloblastoma.

  6. Papiloma vírus humano e o polimorfismo do códon 72 (Alelo-G) do gene TP53 no carcinoma escamoso oral

    OpenAIRE

    Almeida Neto,Adauto

    2007-01-01

    O CEC oral representa 90% de todos os tumores malignos que afetam a boca. A infecção por HPV (Papilomavírus Humano) demonstrou ser um fator relevante no desenvolvimento do carcinoma oral, assim como o polimorfismo do Códon 72 (alelo-G) do gene TP53, cuja transcrição da proteína supressora tumoral p53 é modificado. A degradação da p53 ocorre em função da interação entre a oncoproteína viral E6 junto ao sistema proteolítico ubiqütina-proteossômica. O objetivo deste trabalho...

  7. BRCA1 proteins regulate growth of ovarian cancer cells by tethering Ubc9.

    Science.gov (United States)

    Qin, Yunlong; Xu, Jingyao; Aysola, Kartik; Oprea, Gabriela; Reddy, Avinash; Matthews, Roland; Okoli, Joel; Cantor, Alan; Grizzle, William E; Partridge, Edward E; Reddy, E Shyam P; Landen, Charles; Rao, Veena N

    2012-01-01

    Mutation in the BRCA1 gene is associated with increased risk for hereditary breast and ovarian cancers. In sporadic ovarian tumors, BRCA1 dysfunction is thought to be common. BRCA1 is a nuclear-cytoplasm shuttling protein. Our group has previously reported that BRCA1 proteins, unlike K109R and cancer-predisposing mutant C61G BRCA1 proteins, bind the sole SUMO E2-conjugating enzyme Ubc9. In this study, we examined the result of altered Ubc9 binding and knockdown on the sub-cellular localization and growth inhibitory function of BRCA1 proteins in ovarian cancer cells. Using live imaging of YFP, RFP-tagged BRCA1 and BRCA1a proteins, our results show enhanced cytoplasmic localization of K109R and C61G mutant BRCA1 proteins in ES-2, NIHOVCAR3 and UWB 1.289 ovarian cancer cells. Down-regulation of Ubc9 in ovarian cancer cells using Ubc9 siRNA resulted in cytoplasmic localization of BRCA1 and BRCA1a proteins. These mutant BRCA1a proteins were impaired in their capacity to inhibit growth of ES-2 ovarian cancer cells. Several ovarian cancer cells, including a BRCA1-null ovarian cancer cell line, showed higher levels of expression of Ubc9. This is the first study demonstrating the physiological link between loss of Ubc9 binding and loss of growth suppression of disease-associated mutant BRCA1a proteins in ovarian cancer cells. BRCA1, by turning off or on Ubc9 binding, regulates growth of ovarian cancers.

  8. BRCA1 DNA-binding activity is stimulated by BARD1.

    Science.gov (United States)

    Simons, Amanda M; Horwitz, Andrew A; Starita, Lea M; Griffin, Karen; Williams, R Scott; Glover, J N Mark; Parvin, Jeffrey D

    2006-02-15

    The breast- and ovarian-specific tumor suppressor BRCA1 has been implicated in numerous cellular processes, including transcription, ubiquitination, and DNA repair. Its tumor suppression activity is tightly linked to that of BARD1, a protein that heterodimerizes with BRCA1. It has been previously shown that BRCA1 binds to DNA, an interesting functional observation in light of the genetic data linking BRCA1 to DNA repair pathways. In this work, we reexamine the DNA-binding properties of BRCA1, comparing them with the DNA-binding properties of the BRCA1/BARD1 heterodimer. Because nuclear BRCA1 exists as a heterodimer with BARD1, it is likely that in vitro studies of the heterodimer will provide a more accurate model of physiologic conditions. Our results indicate that whereas BARD1 cannot directly bind DNA, it does enhance DNA binding by BRCA1. This is a surprising observation as both DNA-binding domains are distal to the BARD1-interacting RING domain of BRCA1. Further analysis of the dimerization reveals that the BRCA1/BARD1 interaction is not limited to the amino-terminal RING domains of each protein. The carboxyl terminus of BRCA1 contributes significantly to the stability of the heterodimer. We also show that the presence of BARD1 has a secondary effect, as autoubiquitination of BRCA1/BARD1 heterodimers additionally enhances the affinity of BRCA1 for DNA. Together, these data suggest that BRCA1 and BARD1 heterodimerization is stabilized via domains not previously thought to interact and that BARD1 acts in both ubiquitination-dependent and ubiquitination-independent ways to influence the role of BRCA1 in DNA repair.

  9. NOTCH2 in breast cancer: association of SNP rs11249433 with gene expression in ER-positive breast tumors without TP53 mutations

    Directory of Open Access Journals (Sweden)

    Ambs Stefan

    2010-05-01

    Full Text Available Abstract Background A recent genome-wide association study (GWAS has identified a single nucleotide polymorphism (SNP rs11249433 in the 1p11.2 region as a novel genetic risk factor for breast cancer, and this association was stronger in patients with estrogen receptor (ER+ versus ER- cancer. Results We found association between SNP rs11249433 and expression of the NOTCH2 gene located in the 1p11.2 region. Examined in 180 breast tumors, the expression of NOTCH2 was found to be lowest in tumors with TP53 mutations and highest in TP53 wild-type/ER+ tumors (p = 0.0059. In the latter group, the NOTCH2 expression was particularly increased in carriers of the risk genotypes (AG/GG of rs11249433 when compared to the non-risk AA genotype (p = 0.0062. Similar association between NOTCH2 expression and rs11249433 was observed in 60 samples of purified monocytes from healthy controls (p = 0.015, but not in total blood samples from 302 breast cancer patients and 76 normal breast tissue samples. We also identified the first possible dominant-negative form of NOTCH2, a truncated version of NOTCH2 consisting of only the extracellular domain. Conclusion This is the first study to show that the expression of NOTCH2 differs in subgroups of breast tumors and by genotypes of the breast cancer-associated SNP rs11249433. The NOTCH pathway has key functions in stem cell differentiation of ER+ luminal cells in the breast. Therefore, increased expression of NOTCH2 in carriers of rs11249433 may promote development of ER+ luminal tumors. Further studies are needed to investigate possible mechanisms of regulation of NOTCH2 expression by rs11249433 and the role of NOTCH2 splicing forms in breast cancer development.

  10. Adrenocortical tumors associated with the TP53 p.R337H germline mutation can be identified during child-care consultations.

    Science.gov (United States)

    Mastellaro, Maria J; Ribeiro, Raul C; Oliveira-Filho, Antônio G; Seidinger, Ana L; Cardinalli, Izilda A; Miranda, Eliana C M; Aguiar, Simone S; Brandalise, Silvia R; Yunes, José A; Barros-Filho, Antônio A

    2017-08-30

    To evaluate the clinical features associated with adrenocortical hormone overexpression and familial cancer profiling as potential markers for early detection of adrenocortical tumors in children from South and Southeast Brazil. The clinical manifestations and anthropometric measurements of 103 children diagnosed with adrenocortical tumors were analyzed. Between 1982 and 2011, 69 girls and 34 boys diagnosed with adrenocortical tumors were followed-up for a median time of 9.0 years (0-34 years). Signs of androgen overproduction alone (n=75) or associated with cortisol (n=18) were present in 90.3%. TP53 p.R337H mutation was found in 90.5% of patients. Stages I, II, III, and IV were observed in 45.6%, 27.2%, 19.4%, and 7.8% of patients, respectively. At diagnosis, there were no significant differences in height (p=0.92) and weight (p=0.22) among children with adrenocortical tumors, but children with virilization alone had significantly higher height-for-age Z-scores (0.92±1.4) than children with hypercortisolism alone or combined (-0.32±1,8; p=0.03). The five-year overall survival was 76.7% (SD±4.2). Patients with advanced-stage disease had a significantly worse prognosis than those with limited disease (pp.R337H carrier parents developed cancer, whereas none of the 55 non-carriers did. Signs of adrenocortical hormone overproduction appear early, even in cases with early-stage. These signs can be identified at the physical examination and anthropometric measurements. In southern Brazil, pediatric adrenocortical tumor is a sentinel cancer for detecting families with germline p.R337H mutation in TP53 gene. Copyright © 2017 Sociedade Brasileira de Pediatria. Published by Elsevier Editora Ltda. All rights reserved.

  11. PROGNOSTIC SIGNIFICANCE OF nm23 PROTEIN IN THE TUMORS OF PATIENTS WITH COLORECTAL CANCER

    Directory of Open Access Journals (Sweden)

    D. A. Golovkov

    2016-01-01

    Full Text Available Purpose. Study of expression of protein nm23 inprimary and secondary foci of colorectal cancer (CRC taking in consideration the clinical and morphological features of the disease and the possibility of predicting the risk of distant metastases. Material and methods. The study included postoperative material of 264 CRC patients with I–IV stages of cancer. Immunohistochemical staining performed by biotin-streptavidin immunoperoxidase method on the paraffin tissue sections of primary colon tumors and their metastases in lymph nodes and liver using antibodies against nm23 protein (H‑1 and H‑2 (“Dako”, Denmark. The results were evaluated by semiquantitative method based on the staining intensity and the number of antigen-positive cells and localization of immunoreactivity in cancer cells.Results. During the immunohistochemical study of primary tumors of the colon the increase of the accumulation of nm23 protein was observed in 53.4% (141/264 studied cases. In nmtastasis of CRC the main patterns of expression of a marker characteristic of the corresponding primary tumors was preserved. Survival curves, computed according to the method of Kaplan-Meyer showed that patients with nm23‑positive staining of tumors show a lower 5‑year overall survival than patients with negative immunoreactivity in the tumor. Indicators of disease-free survival in patients with CRC also deteriorated in nm23‑negative status of tumors compared to nm23‑positive status.Conclusion. The overexpression of nm 23 protein were freqently detected in metastasizing primary tumors of colon and their liver metastases and was associated with a high risk of developing distant metastases, and poor outcome of the disease and the deterioration of the postoperative overall and disease-free survival of CRC patients. A high expression level of this marker is a sign of unfavorable prognosis for CRC patients.

  12. Population testing for cancer predisposing BRCA1/BRCA2 mutations

    OpenAIRE

    Wardle, J.

    2014-01-01

    Background: Technological advances raise the possibility of systematic population-based genetic testing for cancer-predisposing mutations, but it is uncertain whether benefits outweigh disadvantages. We directly compared the psychological/quality-of-life consequences of such an approach to family history (FH)–based testing. Methods: In a randomized controlled trial of BRCA1/2 gene-mutation testing in the Ashkenazi Jewish (AJ) population, we compared testing all participants in the...

  13. BRCA 1-Mediated Histone Monoubiquitylation: Effect on Nucleosome Dynamics

    Science.gov (United States)

    2008-02-01

    nucleosome positioning sequence from sea urchin 5s rRNA gene; perform and analyze the ubiquitylation reaction (month 4). Done Task 2: Use single... sea urchin 5S rDNA, and oligonucleosomes were reconstituted on the same sequence repeated in tandem (208-12) (Simpson et al., 1985). Isolation of...Center, Columbus, OH 43210), who provided BRCA1/BARD1 protein complex. b. Acquire and perform quality tests on the other components of the

  14. The multiple nuclear functions of BRCA1: transcription, ubiquitination and DNA repair.

    Science.gov (United States)

    Starita, Lea M; Parvin, Jeffrey D

    2003-06-01

    Interest in BRCA1 stems from its role as a tumour suppressor in breast and ovarian cancer. Intensive research in BRCA1 has revealed little about its specific role in cancer; rather, this protein has been implicated in a multitude of important cellular processes. The diverse biochemical activities of BRCA1 combine to protect the genome from damage. New data reveal that BRCA1 transcriptionally regulates some DNA-repair genes, and, in addition, new roles for BRCA1 have been identified in heterochromatin formation on the X chromosome, double-strand-break repair, and ubiquitination. These diverse activities of BRCA1 may be linked in a single pathway, or BRCA1 might function in multiple nuclear processes.

  15. BRCA1 as a Therapeutic Target in Sporadic Epithelial Ovarian Cancer

    Directory of Open Access Journals (Sweden)

    Katherine V. Clark-Knowles

    2010-01-01

    Full Text Available In sporadic epithelial ovarian cancer (EOC, the inactivation of BRCA1 through various mechanisms is a relatively common event. BRCA1 protein dysfunction results in the breakdown of various critical pathways in the cell, notably, the DNA damage response and repair pathway. Tumors from patients with BRCA1 germline mutations have an increased sensitivity to DNA damaging chemotherapeutic agents, such as cisplatin, due to defective DNA repair. Thus, inhibiting BRCA1 in sporadic EOC using novel targeted therapies is an attractive strategy for the treatment of advanced or recurrent EOC. Several classes of small molecule inhibitors that affect BRCA1 have now been tested in preclinical and clinical studies suggesting that this is a rational therapeutic approach. The aim of this paper is to provide an understanding of how BRCA1 has evolved into a promising target for the treatment of sporadic disease and to outline the main potential small molecule inhibitors of BRCA1 in EOC.

  16. Reanalysis of BRCA1/2 negative high risk ovarian cancer patients reveals novel germline risk loci and insights into missing heritability.

    Science.gov (United States)

    Stafford, Jaime L; Dyson, Gregory; Levin, Nancy K; Chaudhry, Sophia; Rosati, Rita; Kalpage, Hasini; Wernette, Courtney; Petrucelli, Nancie; Simon, Michael S; Tainsky, Michael A

    2017-01-01

    While up to 25% of ovarian cancer (OVCA) cases are thought to be due to inherited factors, the majority of genetic risk remains unexplained. To address this gap, we sought to identify previously undescribed OVCA risk variants through the whole exome sequencing (WES) and candidate gene analysis of 48 women with ovarian cancer and selected for high risk of genetic inheritance, yet negative for any known pathogenic variants in either BRCA1 or BRCA2. In silico SNP analysis was employed to identify suspect variants followed by validation using Sanger DNA sequencing. We identified five pathogenic variants in our sample, four of which are in two genes featured on current multi-gene panels; (RAD51D, ATM). In addition, we found a pathogenic FANCM variant (R1931*) which has been recently implicated in familial breast cancer risk. Numerous rare and predicted to be damaging variants of unknown significance were detected in genes on current commercial testing panels, most prominently in ATM (n = 6) and PALB2 (n = 5). The BRCA2 variant p.K3326*, resulting in a 93 amino acid truncation, was overrepresented in our sample (odds ratio = 4.95, p = 0.01) and coexisted in the germline of these women with other deleterious variants, suggesting a possible role as a modifier of genetic penetrance. Furthermore, we detected loss of function variants in non-panel genes involved in OVCA relevant pathways; DNA repair and cell cycle control, including CHEK1, TP53I3, REC8, HMMR, RAD52, RAD1, POLK, POLQ, and MCM4. In summary, our study implicates novel risk loci as well as highlights the clinical utility for retesting BRCA1/2 negative OVCA patients by genomic sequencing and analysis of genes in relevant pathways.

  17. Prognostic and predictive value of TP53 mutations in node-positive breast cancer patients treated with anthracycline- or anthracycline/taxane-based adjuvant therapy: results from the BIG 02-98 phase III trial.

    Science.gov (United States)

    Fernández-Cuesta, Lynnette; Oakman, Catherine; Falagan-Lotsch, Priscila; Smoth, Ke-Seay; Quinaux, Emmanuel; Buyse, Marc; Dolci, M Stella; Azambuja, Evandro De; Hainaut, Pierre; Dell'orto, Patrizia; Larsimont, Denis; Francis, Prudence A; Crown, John; Piccart-Gebhart, Martine; Viale, Giuseppe; Leo, Angelo Di; Olivier, Magali

    2012-05-02

    Pre-clinical data suggest p53-dependent anthracycline-induced apoptosis and p53-independent taxane activity. However, dedicated clinical research has not defined a predictive role for TP53 gene mutations. The aim of the current study was to retrospectively explore the prognosis and predictive values of TP53 somatic mutations in the BIG 02-98 randomized phase III trial in which women with node-positive breast cancer were treated with adjuvant doxorubicin-based chemotherapy with or without docetaxel. The prognostic and predictive values of TP53 were analyzed in tumor samples by gene sequencing within exons 5 to 8. Patients were classified according to p53 protein status predicted from TP53 gene sequence, as wild-type (no TP53 variation or TP53 variations which are predicted not to modify p53 protein sequence) or mutant (p53 nonsynonymous mutations). Mutations were subcategorized according to missense or truncating mutations. Survival analyses were performed using the Kaplan-Meier method and log-rank test. Cox-regression analysis was used to identify independent predictors of outcome. TP53 gene status was determined for 18% (520 of 2887) of the women enrolled in BIG 02-98. TP53 gene variations were found in 17% (90 of 520). Nonsynonymous p53 mutations, found in 16.3% (85 of 520), were associated with older age, ductal morphology, higher grade and hormone-receptor negativity. Of the nonsynonymous mutations, 12.3% (64 of 520) were missense and 3.6% were truncating (19 of 520). Only truncating mutations showed significant independent prognostic value, with an increased recurrence risk compared to patients with non-modified p53 protein (hazard ratio = 3.21, 95% confidence interval = 1.740 to 5.935, P = 0.0002). p53 status had no significant predictive value for response to docetaxel. p53 truncating mutations were uncommon but associated with poor prognosis. No significant predictive role for p53 status was detected. ClinicalTrials.gov NCT00174655.

  18. Common variants of the BRCA1 wild-type allele modify the risk of breast cancer in BRCA1 mutation carriers.

    NARCIS (Netherlands)

    Cox, D.G.; Simard, J.; Sinnett, D.; Hamdi, Y.; Soucy, P.; Ouimet, M.; Barjhoux, L.; Verny-Pierre, C.; McGuffog, L.; Healey, S.; Szabo, C.; Greene, M.H.; Mai, P.L.; Andrulis, I.L.; Thomassen, M.; Gerdes, A.M.; Caligo, M.A.; Friedman, E.; Laitman, Y.; Kaufman, B.; Paluch, S.S.; Borg, A.; Karlsson, P.; Askmalm, M.S.; Bustinza, G.B.; Nathanson, K.L.; Domchek, S.M.; Rebbeck, T.R.; Benitez, J.; Hamann, U.; Rookus, M.A.; Ouweland, A.M. van den; Ausems, M.G.; Aalfs, C.M.; Asperen, C.J. van; Devilee, P.; Gille, H.J.; Peock, S.; Frost, D.; Evans, D.G.; Eeles, R.; Izatt, L.; Adlard, J.; Paterson, J.; Eason, J.; Godwin, A.K.; Remon, M.A.; Moncoutier, V.; Gauthier-Villars, M.; Lasset, C.; Giraud, S.; Hardouin, A.; Berthet, P.; Sobol, H.; Eisinger, F.; Bressac de Paillerets, B.; Caron, O.; Delnatte, C.; Goldgar, D.; Miron, A.; Ozcelik, H.; Buys, S.; Southey, M.C.; Terry, M.B.; Singer, C.F.; Dressler, A.C.; Tea, M.K.; Hansen, T.V.; Johannsson, O.; Piedmonte, M.; Rodriguez, G.C.; Basil, J.B.; Blank, S.; Toland, A.E.; Montagna, M.; Isaacs, C.; Blanco, I.; Gayther, S.A.; Moysich, K.B.; Schmutzler, R.K.; Wappenschmidt, B.; Engel, C.; Meindl, A.; Ditsch, N.; Arnold, N.; Niederacher, D.; Sutter, C.; Gadzicki, D.; Fiebig, B.; Caldes, T.; Laframboise, R.; Nevanlinna, H.; Chen, X.; Beesley, J.; Spurdle, A.B.; Neuhausen, S.L.; Ding, Y.C.; Couch, F.J.; Wang, X.; Peterlongo, P.; Manoukian, S.; Bernard, L.; Radice, P.; Easton, D.F.; Chenevix-Trench, G.; Antoniou, A.C.; Stoppa-Lyonnet, D.; Mazoyer, S.; Sinilnikova, O.M.; Ligtenberg, M.J.L.; Hoogerbrugge, N.; et al.,

    2011-01-01

    Mutations in the BRCA1 gene substantially increase a woman's lifetime risk of breast cancer. However, there is great variation in this increase in risk with several genetic and non-genetic modifiers identified. The BRCA1 protein plays a central role in DNA repair, a mechanism that is particularly

  19. Common variants of the BRCA1 wild-type allele modify the risk of breast cancer in BRCA1 mutation carriers

    NARCIS (Netherlands)

    Cox, David G.; Simard, Jacques; Sinnett, Daniel; Hamdi, Yosr; Soucy, Penny; Ouimet, Manon; Barjhoux, Laure; Verny-Pierre, Carole; McGuffog, Lesley; Healey, Sue; Szabo, Csilla; Greene, Mark H.; Mai, Phuong L.; Andrulis, Irene L.; Thomassen, Mads; Gerdes, Anne-Marie; Caligo, Maria A.; Friedman, Eitan; Laitman, Yael; Kaufman, Bella; Paluch, Shani S.; Borg, Åke; Karlsson, Per; Askmalm, Marie Stenmark; Bustinza, Gisela Barbany; Nathanson, Katherine L.; Domchek, Susan M.; Rebbeck, Timothy R.; Benítez, Javier; Hamann, Ute; Rookus, Matti A.; van den Ouweland, Ans M. W.; Ausems, Margreet G. E. M.; Aalfs, Cora M.; van Asperen, Christi J.; Devilee, Peter; Gille, Hans J. J. P.; Peock, Susan; Frost, Debra; Evans, D. Gareth; Eeles, Ros; Izatt, Louise; Adlard, Julian; Paterson, Joan; Eason, Jacqueline; Godwin, Andrew K.; Remon, Marie-Alice; Moncoutier, Virginie; Gauthier-Villars, Marion; Lasset, Christine; Giraud, Sophie; Hardouin, Agnès; Berthet, Pascaline; Sobol, Hagay; Eisinger, François; Bressac de Paillerets, Brigitte; Caron, Olivier; Delnatte, Capucine; Goldgar, David; Miron, Alex; Ozcelik, Hilmi; Buys, Saundra; Southey, Melissa C.; Terry, Mary Beth; Singer, Christian F.; Dressler, Anne-Catharina; tea, Muy-Kheng; Hansen, Thomas V. O.; Johannsson, Oskar; Piedmonte, Marion; Rodriguez, Gustavo C.; Basil, Jack B.; Blank, Stephanie; Toland, Amanda E.; Montagna, Marco; Isaacs, Claudine; Blanco, Ignacio; Gayther, Simon A.; Moysich, Kirsten B.; Schmutzler, Rita K.; Wappenschmidt, Barbara; Engel, Christoph; Meindl, Alfons; Ditsch, Nina; Arnold, Norbert; Niederacher, Dieter; Sutter, Christian; Gadzicki, Dorothea; Fiebig, Britta; Caldes, Trinidad; Laframboise, Rachel; Nevanlinna, Heli; Chen, Xiaoqing; Beesley, Jonathan; Spurdle, Amanda B.; Neuhausen, Susan L.; Ding, Yuan C.; Couch, Fergus J.; Wang, Xianshu; Peterlongo, Paolo; Manoukian, Siranoush; Bernard, Loris; Radice, Paolo; Easton, Douglas F.; Chenevix-Trench, Georgia; Antoniou, Antonis C.; Stoppa-Lyonnet, Dominique; Mazoyer, Sylvie; Sinilnikova, Olga M.; Glendon, Gord; Selander, Teresa; Weerasooriya, Nayana; Nordling, Margareta; Bergman, Annika; Einbeigi, Zakaria; Stenmark-Askmalm, Marie; Liedgren, Sigrun; Loman, Niklas; Olsson, Håkan; Kristoffersson, Ulf; Soller, Maria; Jernström, Helena; Harbst, Katja; Henriksson, Karin; Lindblom, Annika; Arver, Brita; von Wachenfeldt, Anna; Liljegren, Annelie; Barbany-Bustinza, Gisela; Rantala, Johanna; Melin, Beatrice; Grönberg, Henrik; Stattin, Eva-Lena; Emanuelsson, Monica; Ehrencrona, Hans; Brandell, Richard Rosenquist; Dahl, Niklas; Hogervorst, F. B. L.; Verhoef, S.; Verheus, M.; van't Veer, L. J.; van Leeuwen, F. E.; Rookus, M. A.; Collée, M.; van den Ouweland, A. M. W.; Jager, A.; Hooning, M. J.; Tilanus-Linthorst, M. M. A.; Seynaeve, C.; van Asperen, C. J.; Wijnen, J. T.; Vreeswijk, M. P.; Tollenaar, R. A.; Devilee, P.; Ligtenberg, M. J.; Hoogerbrugge, N.; Ausems, M. G.; van der Luijt, R. B.; van Os, T. A.; Gille, J. J. P.; Waisfisz, Q.; Meijers-Heijboer, H. E. J.; Gomez-Garcia, E. B.; van Roozendaal, C. E.; Blok, Marinus J.; Caanen, B.; Oosterwijk, J. C.; van der Hout, A. H.; Mourits, M. J.; Vasen, H. F.; Cook, Margaret; Platte, Radka; Miedzybrodzka, Zosia; Gregory, Helen; Morrison, Patrick; Jeffers, Lisa; Cole, Trevor; Ong, Kai-Ren; Hoffman, Jonathan; Donaldson, Alan; James, Margaret; Downing, Sarah; Taylor, Amy; Murray, Alexandra; Rogers, Mark T.; McCann, Emma; Kennedy, M. John; Barton, David; Porteous, Mary; Drummond, Sarah; Brewer, Carole; Kivuva, Emma; Searle, Anne; Goodman, Selina; Hill, Kathryn; Davidson, Rosemarie; Murday, Victoria; Bradshaw, Nicola; Snadden, Lesley; Longmuir, Mark; Watt, Catherine; Gibson, Sarah; Haque, Eshika; Tobias, Ed; Duncan, Alexis; Jacobs, Chris; Langman, Caroline; Whaite, Anna; Dorkins, Huw; Barwell, Julian; Chu, Carol; Miller, Julie; Ellis, Ian; Houghton, Catherine; Lalloo, Fiona; Taylor, Jane; Side, Lucy; Male, Alison; Berlin, Cheryl; Collier, Rebecca; Douglas, Fiona; Claber, Oonagh; Jobson, Irene; Walker, Lisa; McLeod, Diane; Halliday, Dorothy; Durell, Sarah; Stayner, Barbara; Shanley, Susan; Rahman, Nazneen; Houlston, Richard; Bancroft, Elizabeth; D'Mello, Lucia; Page, Elizabeth; Ardern-Jones, Audrey; Kohut, Kelly; Wiggins, Jennifer; Castro, Elena; Mitra, Anita; Robertson, Lisa; Cook, Jackie; Quarrell, Oliver; Bardsley, Cathryn; Hodgson, Shirley; Goff, Sheila; Brice, Glen; Winchester, Lizzie; Eddy, Charlotte; Tripathi, Vishakha; Attard, Virginia; Eccles, Diana; Lucassen, Anneke; Crawford, Gillian; McBride, Donna; Smalley, Sarah; Sinilnikova, Olga; Léone, Mélanie; Buecher, Bruno; Houdayer, Claude; Belotti, Muriel; Tirapo, Carole; de Pauw, Antoine; Bressac-de-Paillerets, Brigitte; Remenieras, Audrey; Byrde, Véronique; Lenoir, Gilbert; Bignon, Yves-Jean; Uhrhammer, Nancy; Bonadona, Valérie; Bourdon, Violaine; Noguchi, Tetsuro; Coulet, Florence; Colas, Chrystelle; Soubrier, Florent; Coupier, Isabelle; Pujol, Pascal; Peyrat, Jean-Philippe; Fournier, Joëlle; Révillion, Françoise; Vennin, Philippe; Adenis, Claude; Rouleau, Etienne; Lidereau, Rosette; Demange, Liliane; Nogues, Catherine; Muller, Danièle; Fricker, Jean-Pierre; Longy, Michel; Sevenet, Nicolas; Toulas, Christine; Guimbaud, Rosine; Gladieff, Laurence; Feillel, Viviane; Leroux, Dominique; Dreyfus, Hèléne; Rebischung, Christine; Coron, Fanny; Faivre, Laurence; Prieur, Fabienne; Lebrun, Marine; Ferrer, Sandra Fert; Frénay, Marc; Vénat-Bouvet, Laurence; Mortemousque, Isabelle; Lynch, Henry T.; Snyder, Carrie L.

    2011-01-01

    Mutations in the BRCA1 gene substantially increase a woman's lifetime risk of breast cancer. However, there is great variation in this increase in risk with several genetic and non-genetic modifiers identified. The BRCA1 protein plays a central role in DNA repair, a mechanism that is particularly

  20. Common variants of the BRCA1 wild-type allele modify the risk of breast cancer in BRCA1 mutation carriers

    DEFF Research Database (Denmark)

    Cox, David G; Simard, Jacques; Sinnett, Daniel

    2011-01-01

    Mutations in the BRCA1 gene substantially increase a woman's lifetime risk of breast cancer. However, there is great variation in this increase in risk with several genetic and non-genetic modifiers identified. The BRCA1 protein plays a central role in DNA repair, a mechanism that is particularly...

  1. Prevalence of deleterious germline variants in risk genes including BRCA1/2 in consecutive ovarian cancer patients (AGO-TR-1.

    Directory of Open Access Journals (Sweden)

    Philipp Harter

    Full Text Available Identification of families at risk for ovarian cancer offers the opportunity to consider prophylactic surgery thus reducing ovarian cancer mortality. So far, identification of potentially affected families in Germany was solely performed via family history and numbers of affected family members with breast or ovarian cancer. However, neither the prevalence of deleterious variants in BRCA1/2 in ovarian cancer in Germany nor the reliability of family history as trigger for genetic counselling has ever been evaluated.Prospective counseling and germline testing of consecutive patients with primary diagnosis or with platinum-sensitive relapse of an invasive epithelial ovarian cancer. Testing included 25 candidate and established risk genes. Among these 25 genes, 16 genes (ATM, BRCA1, BRCA2, CDH1, CHEK2, MLH1, MSH2, MSH6, NBN, PMS2, PTEN, PALB2, RAD51C, RAD51D, STK11, TP53 were defined as established cancer risk genes. A positive family history was defined as at least one relative with breast cancer or ovarian cancer or breast cancer in personal history.In total, we analyzed 523 patients: 281 patients with primary diagnosis of ovarian cancer and 242 patients with relapsed disease. Median age at primary diagnosis was 58 years (range 16-93 and 406 patients (77.6% had a high-grade serous ovarian cancer. In total, 27.9% of the patients showed at least one deleterious variant in all 25 investigated genes and 26.4% in the defined 16 risk genes. Deleterious variants were most prevalent in the BRCA1 (15.5%, BRCA2 (5.5%, RAD51C (2.5% and PALB2 (1.1% genes. The prevalence of deleterious variants did not differ significantly between patients at primary diagnosis and relapse. The prevalence of deleterious variants in BRCA1/2 (and in all 16 risk genes in patients <60 years was 30.2% (33.2% versus 10.6% (18.9% in patients ≥60 years. Family history was positive in 43% of all patients. Patients with a positive family history had a prevalence of deleterious variants

  2. Carboplatin and taxol resistance develops more rapidly in functional BRCA1 compared to dysfunctional BRCA1 ovarian cancer cells.

    Science.gov (United States)

    Busschots, Steven; O'Toole, Sharon; O'Leary, John J; Stordal, Britta

    2015-08-01

    A major risk factor for ovarian cancer is germline mutations of BRCA1/2. It has been found that (80%) of cellular models with acquired platinum or taxane resistance display an inverse resistance relationship, that is collateral sensitivity to the other agent. We used a clinically relevant comparative selection strategy to develop novel chemoresistant cell lines which aim to investigate the mechanisms of resistance that arise from different exposures of carboplatin and taxol on cells having BRCA1 function (UPN251) or dysfunction (OVCAR8). Resistance to carboplatin and taxol developed quicker and more stably in UPN251 (BRCA1-wildtype) compared to OVCAR8 (BRCA1-methylated). Alternating carboplatin and taxol treatment delayed but did not prevent resistance development when compared to single-agent administration. Interestingly, the sequence of drug exposure influenced the resistance mechanism produced. UPN251-6CALT (carboplatin first) and UPN251-6TALT (taxol first) have different profiles of cross resistance. UPN251-6CALT displays significant resistance to CuSO4 (2.3-fold, p=0.004) while UPN251-6TALT shows significant sensitivity to oxaliplatin (0.6-fold, p=0.01). P-glycoprotein is the main mechanism of taxol resistance found in the UPN251 taxane-resistant sublines. UPN251 cells increase cellular glutathione levels (3.0-fold, p=0.02) in response to carboplatin treatment. However, increased glutathione is not maintained in the carboplatin-resistant sublines. UPN251-7C and UPN251-6CALT are low-level resistant to CuSO4 suggesting alterations in copper metabolism. However, none of the UPN251 sublines have alterations in the protein expression of ATP7A or CTR1. The protein expression of BRCA1 and MRP2 is unchanged in the UPN251 sublines. The UPN251 sublines remain sensitive to parp inhibitors veliparib and CEP8983 suggesting that these agents are candidates for the treatment of platinum/taxane resistant ovarian cancer patients. Copyright © 2014 Elsevier Inc. All rights

  3. BRCA1 and its phosphorylation involved in caffeine-inhibitable event upstream of G2 checkpoint

    Science.gov (United States)

    Li, Ning; Zhang, Hong; Wang, Yanling; Hao, Jifang

    2010-07-01

    Caffeine, which specifically inhibits ATM/ATR kinases, efficiently abrogates the ionizing radiation (IR)-induced G2 arrest and increases the sensitivity of various tumor cells to IR. Mechanisms for the effect of caffeine remain to be elucidated. As a target of ATM/ATR kinases, BRCA1 becomes activated and phosphorylated in response to IR. Thus, in this work, we investigated the possible role of BRCA1 in the effect of caffeine on G2 checkpoint and observed how BRCA1 phosphorylation was regulated in this process. For these purposes, the BRCA1 protein level and the phosphorylation states were analyzed by Western blotting by using an antibody against BRCA1 and phospho-specific antibodies against Ser-1423 and Ser-1524 residues in cells exposed to a combination of IR and caffeine. The results showed that caffeine down-regulated IR-induced BRCA1 expression and specifically abolished BRCA1 phosphorylation of Ser-1524, which was followed by an override of G2 arrest by caffeine. In addition, the ability of BRCA1 to transactivate p21 may be required for MCF-7 but not necessary for Hela response to caffeine. These data suggest that BRCA1 may be a potential target of caffeine. BRCA1 and its phosphorylation are most likely to be involved in the caffeine-inhibitable event upstream of G2 arrest.

  4. Transgenic expression of BRCA1 disturbs hematopoietic stem and progenitor cells quiescence and function

    Energy Technology Data Exchange (ETDEWEB)

    Bai, Lin; Shi, Guiying; Zhang, Xu; Dong, Wei; Zhang, Lianfeng, E-mail: zhanglf@cnilas.org

    2013-10-15

    The balance between quiescence and proliferation of HSCs is an important regulator of hematopoiesis. Loss of quiescence frequently results in HSCs exhaustion, which underscores the importance of tight regulation of proliferation in these cells. Studies have indicated that cyclin-dependent kinases are involved in the regulation of quiescence in HSCs. BRCA1 plays an important role in the repair of DNA double-stranded breaks, cell cycle, apoptosis and transcription. BRCA1 is expressed in the bone marrow. However, the function of BRCA1 in HSCs is unknown. In our study, we generated BRCA1 transgenic mice to investigate the effects of BRCA1 on the mechanisms of quiescence and differentiation in HSCs. The results demonstrate that over-expression of BRCA1 in the bone marrow impairs the development of B lymphocytes. Furthermore, BRCA1 induced an increase in the number of LSKs, LT-HSCs, ST-HSCs and MPPs. A competitive transplantation assay found that BRCA1 transgenic mice failed to reconstitute hematopoiesis. Moreover, BRCA1 regulates the expression of p21{sup waf1}/cip1 and p57{sup kip2}, which results in a loss of quiescence in LSKs. Together, over-expression of BRCA1 in bone marrow disrupted the quiescent of LSKs, induced excessive accumulation of LSKs, and disrupted differentiation of the HSCs, which acts through the down-regulated of p21{sup waf1}/cip1 and p57{sup kip2}. - Highlights: • Over-expression of BRCA1 results in impaired B lymphocyte development. • BRCA1 transgenic mice disrupted the quiescent of LSKs, induced excessive accumulation of LSKs. • BRCA1 impairs the function of HSCs through the down-regulated of p21{sup waf1/cip1} and p57{sup kip2}.

  5. Mutational profile and prognostic significance of TP53 in diffuse large B-cell lymphoma patients treated with R-CHOP: report from an International DLBCL Rituximab-CHOP Consortium Program Study

    NARCIS (Netherlands)

    Xu-Monette, Z.Y.; Wu, L.; Visco, C.; Tai, Y.C.; Tzankov, A.; Liu, W.M.; Montes-Moreno, S.; Dybkaer, K.; Chiu, A.; Orazi, A.; Zu, Y.; Bhagat, G.; Richards, K.L.; Hsi, E.D.; Zhao, X.F.; Choi, W.W.; Zhao, X.; Krieken, J.H. van; Huang, Q.; Huh, J.; Ai, W.; Ponzoni, M.; Ferreri, A.J.; Zhou, F.; Kahl, B.S.; Winter, J.N.; Xu, W.; Li, J.; Go, R.S.; Li, Y.; Piris, M.A.; Moller, M.B.; Miranda, R.N.; Abruzzo, L.V.; Medeiros, L.J.; Young, K.H.

    2012-01-01

    TP53 mutation is an independent marker of poor prognosis in patients with diffuse large B-cell lymphoma (DLBCL) treated with cyclophosphamide, hydroxydaunorubicin, vincristine, and prednisone (CHOP) therapy. However, its prognostic value in the rituximab immunochemotherapy era remains undefined. In

  6. BRCA1/2 associated cancer susceptibility: a clinical overview

    Directory of Open Access Journals (Sweden)

    Lypas Georgios

    2016-06-01

    Full Text Available The most frequently identified genetic cause of breast cancer is the germline mutation of BRCA1 and 2 genes. The carriers of these mutations are at high risk for breast and ovarian cancers and increased risk for pancreatic and prostate cancers. Personal and family history are routinely used to identify individuals at risk for carrying such mutations. Genetic counselling is required to guide them through genetic testing and risk management. Positive testing corresponds to a deleterious mutation, whereas negative testing is considered as uninformative; variants of unknown clinical significance are also classified as uninformative.

  7. Gastric Medullary Carcinoma with Sporadic Mismatch Repair Deficiency and a TP53 R273C Mutation: An Unusual Case with Wild-Type BRAF

    Directory of Open Access Journals (Sweden)

    Brett M. Lowenthal

    2017-01-01

    Full Text Available Medullary carcinoma has long been recognized as a subtype of colorectal cancer associated with microsatellite instability and Lynch syndrome. Gastric medullary carcinoma is a very rare neoplasm. We report a 67-year-old male who presented with a solitary gastric mass. Total gastrectomy revealed a well-demarcated, poorly differentiated carcinoma with an organoid growth pattern, pushing borders, and abundant peritumoral lymphocytic response. The prior cytology was cellular with immunohistochemical panel consistent with upper gastrointestinal/pancreaticobiliary origin. Overall, the histopathologic findings were consistent with gastric medullary carcinoma. A mismatch repair panel revealed a mismatch repair protein deficient tumor with loss of MLH1 and PMS2 expression. BRAF V600E immunostain (VE1 and BRAF molecular testing were negative, indicating a wild-type gene. Tumor sequencing of MLH1 demonstrated a wild-type gene, while our molecular panel identified TP53 c.817C>T (p.R273C mutation. These findings were compatible with a sporadic tumor. Given that morphologically identical medullary tumors often occur in Lynch syndrome, it is possible that mismatch repair loss is an early event in sporadic tumors with p53 mutation being a late event. Despite having wild-type BRAF, this tumor is sporadic and unrelated to Lynch syndrome. This case report demonstrates that coordinate ancillary studies are needed to resolve sporadic versus hereditary rare tumors.

  8. Lycopene Extracts from Different Tomato-Based Food Products Induce Apoptosis in Cultured Human Primary Prostate Cancer Cells and Regulate TP53, Bax and Bcl-2 Transcript Expression

    Science.gov (United States)

    Soares, Nathalia da Costa Pereira; Machado, Clara Lima; Trindade, Bruno Boquimpani; Lima, Ingridy Celestino do Canto; Gimba, Etel Rodrigues Pereira; Teodoro, Anderson Junger; Takiya, Christina; Borojevic, Radovan

    2017-01-01

    Carotenoids are the main tomato components, especially lycopene. Lycopene is more bioavailable in tomato processed products than in raw tomatos, since formation of lycopene cis-isomers during food processing and storage may increase its biological activity. In the current study, we evaluated the influence of lycopene extracts (5 mg / mL) from different tomato-based food products (paste, sauce, extract and ketchup) on cell viability and apoptosis on primary human prostate cancer cells (PCa cels) for 96h. Using MTT assay, we observed a significant decrease on primary PCa cell viability upon treatment with lycopene extracted from either 4 tomato-based food products. Flow cytometeric analysis revealed that lycopene from tomato extract and tomato sauce promoted up to fifty-fold increase on the proportion of apoptotic cells, when compared to the control group. Using real time PCR assay, we found that lycopene promoted an upregulation of TP53 and Bax transcript expression and also downregulation of Bcl-2 expression in PCa cells. In conclusion, our data demostrate that cis-lycopene promoted a significant inhibition on primary PCa cell viability, as well as an increase on their apoptotic rates, evidencing that cis-lycopene contained in tomato sauce and extract cain mainly modulate of primary human prostate cancer cell survival. PMID:28345329

  9. Anaplastic Thyroid Carcinoma: A ceRNA Analysis Pointed to a Crosstalk between SOX2, TP53, and microRNA Biogenesis

    Directory of Open Access Journals (Sweden)

    Walter Arancio

    2015-01-01

    Full Text Available It has been suggested that cancer stem cells (CSC may play a central role in oncogenesis, especially in undifferentiated tumours. Anaplastic thyroid carcinoma (ATC has characteristics suggestive of a tumour enriched in CSC. Previous studies suggested that the stem cell factor SOX2 has a preeminent hierarchical role in determining the characteristics of stem cells in SW1736 ATC cell line. In detail, silencing SOX2 in SW1736 is able to suppress the expression of the stem markers analysed, strongly sensitizing the line to treatment with chemotherapeutic agents. Therefore, in order to further investigate the role of SOX2 in ATC, a competing endogenous RNA (ceRNA analysis was conducted in order to isolate new functional partners of SOX2. Among the interactors, of particular interest are genes involved in the biogenesis of miRNAs (DICER1, RNASEN, and EIF2C2, in the control cell cycle (TP53, CCND1, and in mitochondrial activity (COX8A. The data suggest that stemness, microRNA biogenesis and functions, p53 regulatory network, cyclin D1, and cell cycle control, together with mitochondrial activity, might be coregulated.

  10. TP53 and ovarian cancer

    NARCIS (Netherlands)

    M. Schuijer (Monique); P.M.J.J. Berns (Els)

    2003-01-01

    textabstractOvarian cancer represents the fourth most frequent type of cancer among females and is the leading cause of death from gynecological cancer in the western world. This review describes gene alterations in ovarian cancer. Specific emphasis is placed on genetic alterations and the

  11. Mutational pattern of TP53 tumor suppressor gene in human lung cells exposed to air pollution PM{sub 2.5}; Spectre mutationnel de TP53 en reponse a une exposition in vitro a un aerosol atmospherique particulaire PM{sub 2,} {sub 5}

    Energy Technology Data Exchange (ETDEWEB)

    Billet, Sylvain; Paget, Vincent [Universite Lille Nord de France, Lille (France); Unite de Chimie Environnementale et Interactions sur le Vivant, Maison de la Recherche en Environnement Industriel, Universite du Littoral Cote d' Opale, Dunkerque (France); GRECAN, Universite de Caen Basse-Normandie et Centre Regional de Lutte Contre le Cancer Francois Baclesse, Caen (France); Garcon, Guillaume; Verdin, Anthony; Shirali, Pirouz [Universite Lille Nord de France, Lille (France); Unite de Chimie Environnementale et Interactions sur le Vivant, Maison de la Recherche en Environnement Industriel, Universite du Littoral Cote d' Opale, Dunkerque (France); Andre, Veronique; Heutte, Natacha; Sichel, Francois [GRECAN, Universite de Caen Basse-Normandie et Centre Regional de Lutte Contre le Cancer Francois Baclesse, Caen (France)

    2012-01-15

    Environmental exposure to fine airborne particulate matter (PM 2.5) is thought to be responsible for cardiopulmonary diseases, including lung cancer. However, the mechanisms of action potentially involved in PM{sub 2.5} toxicity are not yet fully described. Mutations in the TP53 gene are the most common alterations in human solid tumors. TP53 mutational patterns have sometimes been linked to carcinogen exposure. The purpose of this study was to determine the mutations that alter the functionality of this transcription factor in a model of human epithelial lung cells (A549) exposed to the fine particulate fraction (PM{sub 2.5}) of an atmospheric aerosol sampled under urban and industrial influences. PM{sub 2.5} was collected in Dunkerque City by cascade impaction. Its physicochemical characterization revealed the presence of many inorganic and organic compounds, including some that are known for their toxicity. The search for mutations altering the functionality of the P53 protein was performed 72 h after exposure of A549 cells to PM{sub 2.5} at its lethal concentration at 50% (LC{sub 50}, 118.60 {mu}g/mL = 31.63 {mu}g/cm{sup 2}), using the Functional Analysis of Separated Alleles in Yeast (FASAY). Sixteen mutations altering P53 function were detected after A549 cells exposure to the collected PM{sub 2.5}: eight deletions of one or two nucleotides and eight nucleotide substitutions, mainly transitions A > G and G > A. These mutations are described in the literature as possibly caused by endogenous mechanisms, such as oxidative stress. This kind of alteration can be induced by metal content of the PM{sub 2.5}, as well as by metabolic activation of the organic compounds coated onto its surface. Involvement of oxidative stress in TP53 mutations was confirmed by the detection of an oxidative DNA adduct, 8-hydroxy-2'-deoxyguanosine (8-OHdG), in A549 cells exposed to the collected PM. (authors)

  12. BRCA1 and BRCA2 mutations in ovarian cancer patients from China: ethnic-related mutations in BRCA1 associated with an increased risk of ovarian cancer.

    Science.gov (United States)

    Shi, Tingyan; Wang, Pan; Xie, Caixia; Yin, Sheng; Shi, Di; Wei, Congchong; Tang, Wenbin; Jiang, Rong; Cheng, Xi; Wei, Qingyi; Wang, Qing; Zang, Rongyu

    2017-05-01

    BRCA1/2 are cancer predisposition genes involved in hereditary breast and ovarian cancer (HBOC). Mutation carriers display an increased sensitivity to inhibitors of poly(ADP-ribose) polymerase (PARP). Despite a number of small-size hospital-based studies being previously reported, there is not yet, to our knowledge, precise data of BRCA1/2 mutations among Chinese ovarian cancer patients. We performed a multicenter cohort study including 916 unselected consecutive epithelial ovarian cancer (EOC) patients from eastern China to screen for BRCA1/2 mutations using the next-generation sequencing approach. A total of 153 EOC patients were found to carry pathogenic germline mutations in BRCA1/2, accounting for an overall mutation incidence of 16.7% with the predominance in BRCA1 (13.1%) compared with BRCA2 (3.9%). We identified 53 novel pathogenic mutations, among which the c.283_286delCTTG and the c.4573C > T of BRCA1 were both found in two unrelated patients. More importantly, the most common mutation found in this study, c.5470_5477del8 was most likely to be Chinese population-related without an apparent founder origin. This hot-spot mutation was presumably associated with an increased risk of ovarian cancer. Taken together, germline BRCA1/2 mutations were common in Chinese EOC patients with distinct mutational spectrum compared to Western populations. Our study contributes to the current understanding of BRCA1/2 mutation prevalence worldwide. We recommend BRCA1/2 genetic testing to all Chinese women diagnosed with EOC to identify HBOC families, to provide genetic counseling and clinical management for at-risk relatives. Mutation carriers may also benefit from PARP-targeted therapies. © 2017 UICC.

  13. Identification of BRCA1 Deficiency Using Multi-Analyte Estimation of BRCA1 and Its Repressors in FFPE Tumor Samples from Patients with Triple Negative Breast Cancer.

    Directory of Open Access Journals (Sweden)

    Aruna Korlimarla

    Full Text Available Apart from germ-line BRCA1-mutated breast cancers, a significant proportion of women with sporadic triple negative breast cancer (TNBC sub-type are known to harbour varying levels of BRCA1-dysfuction. There is currently no established diagnostic method to identify these patients.The analysis was performed on 183 primary breast cancer tumor specimens from our longitudinal case-series archived as formalin-fixed-paraffin-embedded (FFPE blocks comprising 71 TNBCs and 112 Hormone receptor positive HER2 negative (HR+HER2- tumors. Transcript levels of BRCA1 and two of its repressors ID4 and microRNA182 were determined by TaqMan quantitative PCR. BRCA1 protein was detected immunohistochemically with the MS110 antibody.The representation of BRCA1 and its repressor ID4 as a ratio led to improved separation of TNBCs from HR+HER2- compared to either measure by itself. We then dichotomised the continuous distribution of each of the three measurements (Protein, MIRNA and transcript:repressor ratio into categories of deficient (0 and adequate (1. A composite BRCA1 Deficiency Score (BDS was computed by the addition of the score for all three measures. Samples deficient on 2 or more measures were deemed to be BRCA1 deficient; and 40% of all TNBCs met this criterion.We propose here a simple multi-level assay of BRCA1 deficiency using the BRCA1:ID4 ratio as a critical parameter that can be performed on FFPE samples in clinical laboratories by the estimation of only 3 bio-markers. The ease of testing will hopefully encourage adoption and clinical validation.

  14. The putative oncogene CEP72 inhibits the mitotic function of BRCA1 and induces chromosomal instability.

    Science.gov (United States)

    Lüddecke, S; Ertych, N; Stenzinger, A; Weichert, W; Beissbarth, T; Dyczkowski, J; Gaedcke, J; Valerius, O; Braus, G H; Kschischo, M; Bastians, H

    2016-05-05

    BRCA1 is a tumor-suppressor gene associated with, but not restricted to, breast and ovarian cancer and implicated in various biological functions. During mitosis, BRCA1 and its positive regulator Chk2 are localized at centrosomes and are required for the regulation of microtubule plus end assembly, thereby ensuring faithful mitosis and numerical chromosome stability. However, the function of BRCA1 during mitosis has not been defined mechanistically. To gain insights into the mitotic role of BRCA1 in regulating microtubule assembly, we systematically identified proteins interacting with BRCA1 during mitosis and found the centrosomal protein Cep72 as a novel BRCA1-interacting protein. CEP72 is frequently upregulated in colorectal cancer tissues and overexpression of CEP72 mirrors the consequences of BRCA1 loss during mitosis. In detail, the overexpression of CEP72 causes an increase in microtubule plus end assembly, abnormal mitotic spindle formation and the induction of chromosomal instability. Moreover, we show that high levels of Cep72 counteract Chk2 as a positive regulator of BRCA1 to ensure proper mitotic microtubule assembly. Thus, CEP72 represents a putative oncogene in colorectal cancer that might negatively regulate the mitotic function of BRCA1 to ensure chromosomal stability.

  15. BRCA1 Interaction of Centrosomal Protein Nlp Is Required for Successful Mitotic Progression*♦

    Science.gov (United States)

    Jin, Shunqian; Gao, Hua; Mazzacurati, Lucia; Wang, Yang; Fan, Wenhong; Chen, Qiang; Yu, Wei; Wang, Mingrong; Zhu, Xueliang; Zhang, Chuanmao; Zhan, Qimin

    2009-01-01

    Breast cancer susceptibility gene BRCA1 is implicated in the control of mitotic progression, although the underlying mechanism(s) remains to be further defined. Deficiency of BRCA1 function leads to disrupted mitotic machinery and genomic instability. Here, we show that BRCA1 physically interacts and colocalizes with Nlp, an important molecule involved in centrosome maturation and spindle formation. Interestingly, Nlp centrosomal localization and its protein stability are regulated by normal cellular BRCA1 function because cells containing BRCA1 mutations or silenced for endogenous BRCA1 exhibit disrupted Nlp colocalization to centrosomes and enhanced Nlp degradation. Its is likely that the BRCA1 regulation of Nlp stability involves Plk1 suppression. Inhibition of endogenous Nlp via the small interfering RNA approach results in aberrant spindle formation, aborted chromosomal segregation, and aneuploidy, which mimic the phenotypes of disrupted BRCA1. Thus, BRCA1 interaction of Nlp might be required for the successful mitotic progression, and abnormalities of Nlp lead to genomic instability. PMID:19509300

  16. Battle brewing over the BRCA1/2 gene patents.

    Science.gov (United States)

    Agovic, Amina

    2010-01-01

    The revolutionary discovery of the DNA and the successful mapping of the human genome have allowed scientists worldwide to engage in an unprecedented research on the cutting-edge biomedical technology such as the genetic engineering (gene-splicing or recombinant DNA). However, as is often the case with modern bio-technologies, genes related innovation is heavily dependent on strong patent protection primarily due to high costs of research and commercialisation in this area. The aim of this paper is to provide a description of the District Court Ruling in the case of Association for Molecular Pathology et al v United States Patent and Trademark Office et al (ACLU v Myriad). In doing so, the article provides information on the relevant background at issues, including a brief introduction to general patentability requirements in relation to genes and the controversy surrounding the patentability of genetic material. The analysis of the complaint filed in the ACLU v Myriad case and the details of the District Court Ruling follows. The paper concludes with an outlook of the future legal actions involving Myriad's BRCA1/2 and the assessment of the potential impact that the BRCA1/2 District Court Ruling and subsequent appeal(s) may have on the American patent law.

  17. Hereditary Ovarian Cancer: Not Only BRCA 1 and 2 Genes

    Directory of Open Access Journals (Sweden)

    Angela Toss

    2015-01-01

    Full Text Available More than one-fifth of ovarian tumors have hereditary susceptibility and, in about 65–85% of these cases, the genetic abnormality is a germline mutation in BRCA genes. Nevertheless, several other suppressor genes and oncogenes have been associated with hereditary ovarian cancers, including the mismatch repair (MMR genes in Lynch syndrome, the tumor suppressor gene, TP53, in the Li-Fraumeni syndrome, and several other genes involved in the double-strand breaks repair system, such as CHEK2, RAD51, BRIP1, and PALB2. The study of genetic discriminators and deregulated pathways involved in hereditary ovarian syndromes is relevant for the future development of molecular diagnostic strategies and targeted therapeutic approaches. The recent development and implementation of next-generation sequencing technologies have provided the opportunity to simultaneously analyze multiple cancer susceptibility genes, reduce the delay and costs, and optimize the molecular diagnosis of hereditary tumors. Particularly, the identification of mutations in ovarian cancer susceptibility genes in healthy women may result in a more personalized cancer risk management with tailored clinical and radiological surveillance, chemopreventive approaches, and/or prophylactic surgeries. On the other hand, for ovarian cancer patients, the identification of mutations may provide potential targets for biologic agents and guide treatment decision-making.

  18. Hereditary ovarian cancer: not only BRCA 1 and 2 genes.

    Science.gov (United States)

    Toss, Angela; Tomasello, Chiara; Razzaboni, Elisabetta; Contu, Giannina; Grandi, Giovanni; Cagnacci, Angelo; Schilder, Russell J; Cortesi, Laura

    2015-01-01

    More than one-fifth of ovarian tumors have hereditary susceptibility and, in about 65-85% of these cases, the genetic abnormality is a germline mutation in BRCA genes. Nevertheless, several other suppressor genes and oncogenes have been associated with hereditary ovarian cancers, including the mismatch repair (MMR) genes in Lynch syndrome, the tumor suppressor gene, TP53, in the Li-Fraumeni syndrome, and several other genes involved in the double-strand breaks repair system, such as CHEK2, RAD51, BRIP1, and PALB2. The study of genetic discriminators and deregulated pathways involved in hereditary ovarian syndromes is relevant for the future development of molecular diagnostic strategies and targeted therapeutic approaches. The recent development and implementation of next-generation sequencing technologies have provided the opportunity to simultaneously analyze multiple cancer susceptibility genes, reduce the delay and costs, and optimize the molecular diagnosis of hereditary tumors. Particularly, the identification of mutations in ovarian cancer susceptibility genes in healthy women may result in a more personalized cancer risk management with tailored clinical and radiological surveillance, chemopreventive approaches, and/or prophylactic surgeries. On the other hand, for ovarian cancer patients, the identification of mutations may provide potential targets for biologic agents and guide treatment decision-making.

  19. Microdissecção e captura a laser na investigação do gene TP53 em tecidos incluídos em parafina Laser-capture microdissection for TP53 gene analysis in paraffin-embedded tissues

    Directory of Open Access Journals (Sweden)

    Shadia Muhammad Ihlaseh

    2007-02-01

    Full Text Available INTRODUÇÃO: Microdissecção e captura a laser (MCL é uma técnica de desenvolvimento recente que permite a coleta de células individuais ou pequeno conjunto de células para análise molecular. Atualmente, no Brasil, há raros microscópios para MCL, de modo que a divulgação dos procedimentos inerentes a essa técnica é oportuna para destacar seu amplo potencial para diagnóstico e investigação. OBJETIVO: Este trabalho descreve a padronização dos procedimentos de MCL e de extração de DNA de material fixado em formalina e incluído em parafina. MATERIAL E MÉTODOS: Foram estudados o éxon 8 do gene TP53 e o gene da ciclofilina em amostras de tecido normal e de neoplasias de fígado e rim provenientes de modelo de carcinogênese química induzida em rato. A extração do DNA foi comprovada por reação em cadeia da polimerase (nested-PCR. RESULTADOS: Foram padronizados os procedimentos de preparo dos cortes histológicos, de microdissecção e captura a laser e de obtenção de seqüências gênicas pela reação de nested-PCR para tecidos incluídos em parafina. Obtivemos amplificação de 48,3% das amostras para o éxon 8 do gene TP53 e 51,7% para o gene da ciclofilina. Considerando pelo menos um dos dois segmentos gênicos, foram amplificadas 79,3% das amostras. DISCUSSÃO E CONCLUSÃO: A extração de DNA de tecidos fixados em formalina e incluídos em parafina e a técnica de nested-PCR foram adequadamente padronizadas para produtos gênicos de interesse, obtidos de material coletado por MCL. Esses procedimentos podem ser úteis para a obtenção de seqüências de DNA de arquivos para análise molecular.BACKGORUND: Laser-capture micro-dissection (LCM is a recently developed procedure that provides single cells or specific cell groups for molecular analysis. Currently, there are few LCM systems in Brazil, in such a way that it is necessary to disseminate the technical procedures inherent to the methodology, and also to

  20. BRCA1/2-negative hereditary triple-negative breast cancers exhibit BRCAness.

    Science.gov (United States)

    Domagala, Pawel; Hybiak, Jolanta; Cybulski, Cezary; Lubinski, Jan

    2017-04-01

    BRCA1/2-associated breast cancers are sensitive to poly(ADPribose) polymerase (PARP) inhibitors and platinum compounds mainly due to their deficiency in DNA repair via homologous recombination (HR). However, approximately only 15% of triple-negative breast cancers (TNBCs) are BRCA1/2-associated. TNBCs that exhibit BRCAness (a phenotype reflecting impaired HR in BRCA1/2-negative tumors) are also regarded sensitive to PARP inhibitors and platinum compounds. Thus, we hypothesized that hereditary BRCA1/2-negative TNBCs may exhibit BRCAness. To find a subset of hereditary BRCA1/2-negative TNBCs among 360 TNBCs, we first identified a group of 41 hereditary TNBCs by analyzing the family histories of the patients. Next, we tested this group for the presence of germline BRCA1/2 mutations, and finally, we compared the expression levels of 120 genes involved in HR and five other major mechanisms of DNA damage repair between BRCA1/2-associated and BRCA1/2-negative subgroups of hereditary TNBCs using real-time PCR arrays. Approximately 73% of the hereditary TNBCs were BRCA1/2-associated and 27% were BRCA1/2-negative. The expression levels of the analyzed genes showed no significant differences between these two subgroups indicating the BRCAness of the BRCA1/2-negative hereditary TNBCs and thereby distinguishing a novel subset of TNBCs as a potential target for PARP inhibitors or platinum-based therapy. The results show the significance of family history in selecting patients with TNBC for therapies directed at incompetent DNA repair (e.g., PARP inhibitors and/or platinum-based therapies) and indicate that a relatively simple strategy for broadening the target group for these modes of treatment is to identify patients with hereditary TNBCs. © 2016 UICC.

  1. BRCA1 deficiency increases the sensitivity of ovarian cancer cells to auranofin

    Energy Technology Data Exchange (ETDEWEB)

    Oommen, Deepu [School of Biological Sciences, Plymouth University, Plymouth PL4 8AA (United Kingdom); Yiannakis, Dennis [Plymouth Oncology Centre, Derriford Hospital, Plymouth Hospitals NHS Trust, Plymouth PL6 8DH (United Kingdom); Jha, Awadhesh N., E-mail: a.jha@plymouth.ac.uk [School of Biological Sciences, Plymouth University, Plymouth PL4 8AA (United Kingdom)

    2016-02-15

    Highlights: • BRCA1 deficient cancer cells exhibit increased DNA damage upon auranofin treatment. • Auranofin induces apoptosis in BRCA1 deficient cancer cells despite the activation of Nrf2. • Antioxidant protects BRCA1 deficient cancer cells from auranofin. - Abstract: Auranofin, a thioredoxin reductase inhibitor and an anti-rheumatic drug is currently undergoing phase 2 clinical studies for repurposing to treat recurrent epithelial ovarian cancer. Previous studies have established that auranofin exerts its cytotoxic activity by increasing the production of reactive oxygen species (ROS). Breast cancer 1, early onset (BRCA1) is a DNA repair protein whose functional status is critical in the prognosis of ovarian cancer. Apart from its key role in DNA repair, BRCA1 is also known to modulate cellular redox homeostasis by regulating the stability of anti-oxidant transcription factor, nuclear factor erythroid 2—related factor 2 (Nrf2) via direct protein–protein interaction. However, it is currently unknown whether BRCA1 modulates the sensitivity of ovarian cancer cells to auranofin. Here we report that BRCA1-depleted cells exhibited increased DNA double strand breaks (DSBs) and decreased clonogenic cell survival upon auranofin treatment. Interestingly, auranofin induced the expression of Nrf2 in BRCA1-depleted cells suggesting its regulation independent of BRCA1. Furthermore, anti-oxidant agent, N-acetyl cysteine (NAC) protected BRCA1-depleted cells from DNA damage and apoptosis induced by auranofin. Our study suggests that accumulated lethal DSBs resulting from the oxidative damage render BRCA1 deficient cells more sensitive to auranofin despite the activation of Nrf2.

  2. Aflatoxin-induced TP53 R249S mutation in hepatocellular carcinoma in Thailand: association with tumors developing in the absence of liver cirrhosis.

    Directory of Open Access Journals (Sweden)

    Stephanie Villar

    Full Text Available Primary Liver Cancer (PLC is the leading cause of death by cancer among males in Thailand and the 3(rd among females. Most cases are hepatocellular carcinoma (HCC but cholangiocarcinomas represent between 4 and 80% of liver cancers depending upon geographic area. Most HCC are associated with chronic infection by Hepatitis B Virus while a G → T mutation at codon 249 of the TP53 gene, R249S, specific for exposure to aflatoxin, is detected in tumors for up to 30% of cases. We have used Short Oligonucleotide Mass Analysis (SOMA to quantify free circulating R249S-mutated DNA in plasma using blood specimens collected in a hospital case:control study. Plasma R249S-mutated DNA was detectable at low concentrations (≥ 67 copies/mL in 53 to 64% of patients with primary liver cancer or chronic liver disease and in 19% of controls. 44% of patients with HCC and no evidence of cirrhosis had plasma concentrations of R249S-mutated DNA ≥ 150 copies/mL, compared to 21% in patients with both HCC and cirrhosis, 22% in patients with cholangiocarcinoma, 12% in patients with non-cancer chronic liver disease and 3% of subjects in the reference group. Thus, plasma concentrations of R249S-mutated DNA ≥ 150 copies/mL tended to be more common in patients with HCC developing without pre-existing cirrhosis (p = 0.027. Overall, these results support the preferential occurrence of R249S-mutated DNA in HCC developing in the absence of cirrhosis in a context of HBV chronic infection.

  3. The Impact of Smoking and TP53 mutations in lung adenocarcinoma patients with targetable mutations - the Lung Cancer Mutation Consortium (LCMC2).

    Science.gov (United States)

    Aisner, Dara L; Sholl, Lynette M; Berry, Lynne; Rossi, Michael; Chen, Heidi; Fujimoto, Junya; Moreira, Andre L; Ramalingam, Suresh; Villaruz, Liza C; Otterson, Gregory A; Haura, Eric B; Politi, Katerina; Glisson, Bonnie S; Cetnar, Jeremy; Garon, Edward; Schiller, Joan; Waqar, Saiama; Sequist, Lecia V; Brahmer, Julie R; Shyr, Yu; Kugler, Kelly; Wistuba, Ignacio Ivan; Johnson, Bruce E; Minna, John D; Kris, Mark G; Bunn, Paul A; Kwiatkowski, David J

    2017-12-07

    PURPOSE Multiplex genomic profiling is standard of care for patients with advanced lung adenocarcinomas. The Lung Cancer Mutation Consortium (LCMC) is a multi-institutional effort to identify and treat oncogenic driver events in patients with lung adenocarcinomas. PATIENTS AND METHODS Sixteen U.S. institutions enrolled 1367 lung cancer patients in LCMC2; 904 were deemed eligible and had at least one of 14 cancer-related genes profiled using validated methods including genotyping, massively parallel sequencing, and immunohistochemistry. RESULTS The use of targeted therapies in patients with EGFR, ERBB2, or BRAF p.V600E mutations, ALK, ROS1 or RET rearrangements, or MET amplification was associated with a survival increment of 1.5 years compared to those with such mutations not receiving targeted therapy; and 1.0 year compared to those lacking a targetable driver. Importantly, 60 patients with a history of smoking derived similar survival benefit from targeted therapy for alterations in EGFR ALK/ROS1, when compared to 75 never smokers with the same alterations. In addition, co-existing TP53 mutations were associated with shorter survival among patients with EGFR, ALK, or ROS1 alterations. CONCLUSION Patients with adenocarcinoma of the lung and an oncogenic driver mutation treated with effective targeted therapy have a longer survival, regardless of prior smoking history. Molecular testing should be performed on all individuals with lung adenocarcinomas irrespective of clinical characteristics. Routine use of massively parallel sequencing enables detection of both targetable driver alterations and tumor suppressor gene and other alterations that have potential significance for therapy selection and as predictive markers for the efficacy of treatment. Copyright ©2017, American Association for Cancer Research.

  4. Overexpression of centromere protein K (CENP-K) gene in hepatocellular carcinoma promote cell proliferation by activating AKT/TP53 signal pathway.

    Science.gov (United States)

    Wang, Haiyan; Liu, Weilong; Liu, Lei; Wu, Chi; Wu, Weigang; Zheng, Juan; Zhang, Mingxia; Chen, Xinchun; Zhou, Boping; Gao, Zhiliang; Huang, Jian

    2017-09-26

    Hepatocellular carcinoma (HCC) is one of the high-incidence malignant tumors with very poor prognosis. Identification of potential oncogenes is critical to discovering novel therapeutic targets for many cancers, including HCC. In our previous studies, using microarray technology, we conformed that CENP-K was overexpressed in HCCs. However, whether the overexpression of CENP-K contributes to hepatocarcinogenesis remains unclear. In this study, we found that CENP-K was significantly up-regulated in 60% (63 of 105) of HCC specimens at the mRNA level compared to adjacent non-cancerous liver specimens, as determined by RT-qPCR. Immunohistochemical staining confirmed similar results at the protein level. Interestingly, we found that the DNA methylation status of the CENP-K promoter was significantly reduced in HCC specimens with increased CENP-K expression. In addition, CENP-K mRNA expression level was positively correlated with the level of alpha-fetoprotein (AFP) (≥ 400 ng/ml) and tumor size (≥ 3 cm) (p K overexpression promoted proliferation and migration in SMMC7721 and Focus cells. In contrast, knock down of CENP-K significantly inhibited the growth of MHCC-LM3 and QGY7703 cells. Furthermore, we found that overexpression of CENP-K stimulated the tyrosine phosphorylation of the AKT and MDM2 proteins, but inhibited tyrosine phosphorylation of the TP53 protein. Our data suggest that the up-regulation of CENP-K, a potential oncotarget gene, may be modulated by epigenetic events and can contribute to hepatocarcinogenesis.

  5. Hot Spot Mutation in TP53 (R248Q Causes Oncogenic Gain-of-Function Phenotypes in a Breast Cancer Cell Line Derived from an African American patient

    Directory of Open Access Journals (Sweden)

    Nataly Shtraizent

    2015-12-01

    Full Text Available African American (AA breast cancer patients often have triple negative breast cancer (TNBC that contains mutations in the TP53 gene. The point mutations at amino acid residues R273 and R248 both result in oncogenic gain-of-function (GOF phenotypes. Expression of mutant p53 (mtp53 R273H associates with increased cell elasticity, survival under serum deprivation conditions, and increased Poly (ADP ribose polymerase 1 (PARP1 on the chromatin in the AA-derived TNBC breast cancer cell line MDA-MB-468. We hypothesized that GOF mtp53 R248Q expression could stimulate a similar phenotype in the AA-derived TNBC cell line HCC70. To test this hypothesis we depleted the R248Q protein in the HCC70 cell line using shRNA-mediated knockdown. Using impedance-based real-time analysis we correlated the expression of mtp53 R248Q with increased cell deformability. We also documented that depletion of mtp53 R248Q increased PARP1 in the cytoplasm and decreased PARP1 on the chromatin. We conclude that in the AA-derived TNBC HCC70 cells mtp53 R248Q expression results in a causative tumor associated phenotype. This study supports using the biological markers of high expression of mtp53 R273H or R248Q as additional diagnostics for TNBC resistant subtypes often found in the AA community. Each mtp53 protein must be considered separately and this work adds R248Q to the increasing list of p53 mutations that can be used for diagnostics and drug targeting. Here we report that when R248Q mtp53 proteins are expressed in TNBC, then targeting the gain-of-function pathways may improve treatment efficacy.

  6. The mechanism of metastasis suppressor gene nm23-H1 involving in the Ras signaling of lung cancer

    Directory of Open Access Journals (Sweden)

    Xueqin YANG

    2008-10-01

    Full Text Available Background and objective It has been confirmed that nm23-H1 gene is one of the tumor metastasis suppressor genes. Up to now, the exact mechanism of nm23-H1 gebe is uncertain. The aim of this study the mechanism of metastasis suppressor gene nm23-H1 involving in the Ras signaling of lung cancer. Methods The wild and mutant typeof pEGFP-nm23-H1 plasmids [WT (wild type, H118F, S120G, P96S, S44A] were transfected into the L9981 lung cancer cell lines through liposome method, and the complex of KSR and nm23-H1 was detected through co-immunoprecipitation and Western blot assay. Results The human KSR could be detected in the nm23-H1 immunoprecipitations in all the trasfected L9981 lung cancer cell lines. But no significant difference of KSR expression was found in the wild and mutantnm23-H1 trasfected cell lines (F =0.190, P =0.938. Conclusion There was a close interaction between nm23-H1 and KSR, which was independent of the nm23-H1 mutation. Nm23-H1 involving in the Ras signaling of lung cancer may be through the KSR gene.

  7. Checkpoint kinase 2-mediated phosphorylation of BRCA1 regulates the fidelity of nonhomologous end-joining

    NARCIS (Netherlands)

    J. Zhuang; J. Zhang (Shuzhong); H. Willers; H. Wang (Hong); J.H. Chung; D.C. van Gent (Dik); D.E. Hallahan; S.N. Powell; F. Xia

    2006-01-01

    textabstractThe tumor suppressor gene BRCA1 maintains genomic integrity by protecting cells from the deleterious effects of DNA double-strand breaks (DSBs). Through its interactions with the checkpoint kinase 2 (Chk2) kinase and Rad51, BRCA1 promotes homologous recombination, which

  8. Male breast cancer in BRCA1 and BRCA2 mutation carriers

    DEFF Research Database (Denmark)

    Silvestri, Valentina; Barrowdale, Daniel; Mulligan, Anna Marie

    2016-01-01

    BACKGROUND: BRCA1 and, more commonly, BRCA2 mutations are associated with increased risk of male breast cancer (MBC). However, only a paucity of data exists on the pathology of breast cancers (BCs) in men with BRCA1/2 mutations. Using the largest available dataset, we determined whether MBCs aris...

  9. Modification of BRCA1 Breast Cancer Risk by Coffee Consumption: Potential Mechanisms for Biologic Effect

    National Research Council Canada - National Science Library

    Holt, Jeffrey

    2007-01-01

    The purpose of this study was to investigate the role of coffee and caffeine in the function of the DNA repair protein BRCA1 and to determine whether or not coffee and/or caffeine prevent BRCA1 hereditary breast cancer...

  10. Targeted prostate cancer screening in BRCA1 and BRCA2 mutation carriers

    DEFF Research Database (Denmark)

    Bancroft, Elizabeth K; Page, Elizabeth C; Castro, Elena

    2014-01-01

    AND PARTICIPANTS: We recruited men aged 40-69 yr with germline BRCA1/2 mutations and a control group of men who have tested negative for a pathogenic BRCA1 or BRCA2 mutation known to be present in their families. All men underwent prostate-specific antigen (PSA) testing at enrollment, and those men with PSA >3 ng...

  11. Prevalence of BRCA1 in a hospital-based population of Dutch breast cancer patients

    NARCIS (Netherlands)

    Papelard, H; de Bock, GH; van Eijk, R; Vlieland, TPMV; Cornelisse, CJ; Devilee, P; Tollenaar, RAEM

    The prevalence of disease-related BRCA1 mutations was investigated in 642 Dutch breast cancer patients not selected for family history or age at diagnosis. They were tested for germline mutations in the BRCA1 gene using an assay which detects small deletions and insertions (DSDI), as well as the two

  12. Breast cancer after prophylactic bilateral mastectomy in women with a BRCA1 or BRCA2 mutation

    NARCIS (Netherlands)

    Meijers-Heijboer, H.; van Geel, B.; van Putten, W. L.; Henzen-Logmans, S. C.; Seynaeve, C.; Menke-Pluymers, M. B.; Bartels, C. C.; Verhoog, L. C.; van den Ouweland, A. M.; Niermeijer, M. F.; Brekelmans, C. T.; Klijn, J. G.

    2001-01-01

    Women with a BRCA1 or BRCA2 mutation have a high risk of breast cancer and may choose to undergo prophylactic bilateral total mastectomy. We investigated the efficacy of this procedure in such women. We conducted a prospective study of 139 women with a pathogenic BRCA1 or BRCA2 mutation who were

  13. Identification of a founder BRCA1 mutation in the Moroccan population.

    Science.gov (United States)

    Quiles, F; Teulé, À; Martinussen Tandstad, N; Feliubadaló, L; Tornero, E; Del Valle, J; Menéndez, M; Salinas, M; Wethe Rognlien, V; Velasco, A; Izquierdo, A; Capellá, G; Brunet, J; Lázaro, C

    2016-10-01

    Breast cancer (BC) is the most frequent cancer among women in Morocco. However, the role of the most prevalent BC-predisposing genes, BRCA1 and BRCA2, has been largely unexplored. To help define the role of BRCA1 in BC in Morocco, we characterized the first potential BRCA1 founder mutation in this population. Genetic testing of BRCA1 and BRCA2 in BC high-risk families identified mutation BRCA1 c.5309G>T, p.(Gly1770Val) or G1770V in five independent families from Morocco, suggesting a founder effect. To confirm this hypothesis, haplotype construction was performed using seven intragenic and flanking BRCA1 microsatellite markers. Clinical data were also compiled. Clinical data from carriers of mutation G1770V correspond to data from carriers of BRCA1 pathogenic mutations. Microsatellite analysis showed a common haplotype for the five families in a region comprising 1.54 Mb, confirming G1770V as the first specific founder BRCA1 mutation in the Moroccan population. Our findings contribute to a better understanding of BC genetics in the Moroccan population. Nevertheless, comprehensive studies of mutation G1770V in large series of BC patients from Morocco are needed to assess the real prevalence of this mutation and to improve genetic testing and risk assessment in this population. © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  14. Male breast cancer in BRCA1 and BRCA2 mutation carriers

    DEFF Research Database (Denmark)

    Silvestri, Valentina; Barrowdale, Daniel; Mulligan, Anna Marie

    2016-01-01

    BACKGROUND: BRCA1 and, more commonly, BRCA2 mutations are associated with increased risk of male breast cancer (MBC). However, only a paucity of data exists on the pathology of breast cancers (BCs) in men with BRCA1/2 mutations. Using the largest available dataset, we determined whether MBCs...

  15. Mutational analysis of the BRCA1 gene in 30 Czech ovarian cancer ...

    Indian Academy of Sciences (India)

    Unknown

    Ovarian cancer is one of the most severe of oncological diseases. Inherited mutations in cancer susceptibility genes play a causal role in 5–10% of newly diagnosed tumours. BRCA1 and BRCA2 gene alterations are found in the major- ity of these cases. The aim of this study was to analyse the BRCA1 gene in the ovarian ...

  16. Analysis of BRCA1 involvement in breast cancer in Indian women

    Indian Academy of Sciences (India)

    The involvement of the familial breast-ovarian cancer gene (BRCA1) in the molecular pathogenesis of breast cancer among Indian women is unknown. We have used a set of microsatellite polymorphisms to examine the frequency of allele loss at the BRCA1 region on chromosome 17q21, in a panel of 80 human breast ...

  17. Identification and treatment of patients with BRCA1 or BRCA2-defective breast and ovarian cancer

    NARCIS (Netherlands)

    Schouten, P.C.

    2017-01-01

    Inactivating mutations in BRCA1 or BRCA2 confer a large lifetime risk of breast and ovarian cancer. These genes are involved in high-fidelity repair of DNA double strand breaks. Although defects in BRCA1 and BRCA2 are contributing to tumorigenesis, they may also form therapeutic targets. We

  18. Tamoxifen and Risk of Contralateral Breast Cancer for BRCA1 and BRCA2 Mutation Carriers

    DEFF Research Database (Denmark)

    Phillips, Kelly-Anne; Milne, Roger L; Rookus, Matti A

    2013-01-01

    To determine whether adjuvant tamoxifen treatment for breast cancer (BC) is associated with reduced contralateral breast cancer (CBC) risk for BRCA1 and/or BRCA2 mutation carriers.......To determine whether adjuvant tamoxifen treatment for breast cancer (BC) is associated with reduced contralateral breast cancer (CBC) risk for BRCA1 and/or BRCA2 mutation carriers....

  19. Centrosomal microtubule nucleation activity is inhibited by BRCA1-dependent ubiquitination.

    Science.gov (United States)

    Sankaran, Satish; Starita, Lea M; Groen, Aaron C; Ko, Min Ji; Parvin, Jeffrey D

    2005-10-01

    In this study we find that the function of BRCA1 inhibits the microtubule nucleation function of centrosomes. In particular, cells in early S phase have quiescent centrosomes due to BRCA1 activity, which inhibits the association of gamma-tubulin with centrosomes. We find that modification of either of two specific lysine residues (Lys-48 and Lys-344) of gamma-tubulin, a known substrate for BRCA1-dependent ubiquitination activity, led to centrosome hyperactivity. Interestingly, mutation of gamma-tubulin lysine 344 had a minimal effect on centrosome number but a profound effect on microtubule nucleation function, indicating that the processes regulating centrosome duplication and microtubule nucleation are distinct. Using an in vitro aster formation assay, we found that BRCA1-dependent ubiquitination activity directly inhibits microtubule nucleation by centrosomes. Mutant BRCA1 protein that was inactive as a ubiquitin ligase did not inhibit aster formation by the centrosome. Further, a BRCA1 carboxy-terminal truncation mutant that was an active ubiquitin ligase lacked domains critical for the inhibition of centrosome function. These experiments reveal an important new functional assay regulated by the BRCA1-dependent ubiquitin ligase, and the results suggest that the loss of this BRCA1 activity could cause the centrosome hypertrophy and subsequent aneuploidy typically found in breast cancers.

  20. BRCA1-dependent ubiquitination of gamma-tubulin regulates centrosome number.

    Science.gov (United States)

    Starita, Lea M; Machida, Yuka; Sankaran, Satish; Elias, Joshua E; Griffin, Karen; Schlegel, Brian P; Gygi, Steven P; Parvin, Jeffrey D

    2004-10-01

    Proper centrosome duplication and spindle formation are crucial for prevention of chromosomal instability, and BRCA1 plays a role in this process. In this study, transient inhibition of BRCA1 function in cell lines derived from mammary tissue caused rapid amplification and fragmentation of centrosomes. Cell lines tested that were derived from nonmammary tissues did not amplify the centrosome number in this transient assay. We tested whether BRCA1 and its binding partner, BARD1, ubiquitinate centrosome proteins. Results showed that centrosome components, including gamma-tubulin, are ubiquitinated by BRCA1/BARD1 in vitro. The in vitro ubiquitination of gamma-tubulin was specific, and function of the carboxy terminus was necessary for this reaction; truncated BRCA1 did not ubiquitinate gamma-tubulin. BRCA1/BARD1 ubiquitinated lysines 48 and 344 of gamma-tubulin in vitro, and expression in cells of gamma-tubulin K48R caused a marked amplification of centrosomes. This result supports the notion that the modification of these lysines in living cells is critical in the maintenance of centrosome number. One of the key problems in understanding the biology of BRCA1 has been the identification of a specific target of BRCA1/BARD1 ubiquitination and its effect on mammary cell biology. The results of this study identify a ubiquitination target and suggest a biological impact important in the etiology of breast cancer.

  1. BRCA1-Dependent Ubiquitination of γ-Tubulin Regulates Centrosome Number

    Science.gov (United States)

    Starita, Lea M.; Machida, Yuka; Sankaran, Satish; Elias, Joshua E.; Griffin, Karen; Schlegel, Brian P.; Gygi, Steven P.; Parvin, Jeffrey D.

    2004-01-01

    Proper centrosome duplication and spindle formation are crucial for prevention of chromosomal instability, and BRCA1 plays a role in this process. In this study, transient inhibition of BRCA1 function in cell lines derived from mammary tissue caused rapid amplification and fragmentation of centrosomes. Cell lines tested that were derived from nonmammary tissues did not amplify the centrosome number in this transient assay. We tested whether BRCA1 and its binding partner, BARD1, ubiquitinate centrosome proteins. Results showed that centrosome components, including γ-tubulin, are ubiquitinated by BRCA1/BARD1 in vitro. The in vitro ubiquitination of γ-tubulin was specific, and function of the carboxy terminus was necessary for this reaction; truncated BRCA1 did not ubiquitinate γ-tubulin. BRCA1/BARD1 ubiquitinated lysines 48 and 344 of γ-tubulin in vitro, and expression in cells of γ-tubulin K48R caused a marked amplification of centrosomes. This result supports the notion that the modification of these lysines in living cells is critical in the maintenance of centrosome number. One of the key problems in understanding the biology of BRCA1 has been the identification of a specific target of BRCA1/BARD1 ubiquitination and its effect on mammary cell biology. The results of this study identify a ubiquitination target and suggest a biological impact important in the etiology of breast cancer. PMID:15367667

  2. DNA repair capacity is impaired in healthy BRCA1 heterozygous mutation carriers.

    Science.gov (United States)

    Vaclová, Tereza; Gómez-López, Gonzalo; Setién, Fernando; Bueno, José María García; Macías, José Antonio; Barroso, Alicia; Urioste, Miguel; Esteller, Manel; Benítez, Javier; Osorio, Ana

    2015-07-01

    BRCA1 germline mutations increase the lifetime risk of developing breast and ovarian cancers. However, taking into account the differences in disease manifestation among mutation carriers, it is probable that different BRCA1 mutations have distinct haploinsufficiency effects and lead to the formation of different phenotypes. Using lymphoblastoid cell lines derived from heterozygous BRCA1 mutation carriers and non-carriers, we investigated the haploinsufficiency effects of various mutation types using qPCR, immunofluorescence, and microarray technology. Lymphoblastoid cell lines carrying a truncating mutation showed significantly lower BRCA1 mRNA and protein levels and higher levels of gamma-H2AX than control cells or those harboring a missense mutation, indicating greater spontaneous DNA damage. Cells carrying either BRCA1 mutation type showed impaired RAD51 foci formation, suggesting defective repair in mutated cells. Moreover, compared to controls, cell lines carrying missense mutations displayed a more distinct expression profile than cells with truncating mutations, which is consistent with different mutations giving rise to distinct phenotypes. Alterations in the immune response pathway in cells harboring missense mutations point to possible mechanisms of breast cancer initiation in carriers of these mutations. Our findings offer insight into how various heterozygous mutations in BRCA1 could lead to impairment of BRCA1 function and provide strong evidence of haploinsufficiency in BRCA1 mutation carriers.

  3. Characterization of RACK7 as a Novel Factor Involved in BRCA1 Mutation Mediated Breast Cancer

    Science.gov (United States)

    2012-10-01

    transcribed RNA polymerase II genes are impediments to replication fork progression in Saccharomyces cerevisiae . Mol Cell 34, 722-734 (2009). 18 11. Zou...isolated from adult mice containing one BRCA1 null allele and one floxed BRCA1 allele as described [36]. The cells were cultured in DMEM/F12 (1:1) medium

  4. BRCA1 and BRCA2 expression patterns and prognostic significance in digestive system cancers.

    Science.gov (United States)

    Wang, Gui-Hua; Zhao, Chun-Mei; Huang, Ying; Wang, Wei; Zhang, Shu; Wang, Xudong

    2017-11-07

    The role of BRCA1 and BRCA2 genes is mainly to maintain genome integrity in response to DNA damage through different mechanisms. Deregulation of BRCA1 and BRCA2 is associated with the development of tumor and altered sensitivity to chemotherapeutic agents. In this study, we determined protein expression of BRCA1 and BRCA2 in four digestive system cancers (gastric cancer, colorectal cancer, hepatocellular carcinoma, and pancreatic cancer) by immunohistochemistry (IHC) on tissue microarrays. A total of 1546 samples of four types of cancer tissues, their matched adjacent non-tumor tissues, and corresponding benign tissues were studied respectively. IHC expression patterns of the two proteins and their correlation with patients' clinical parameters and overall survival were analyzed. The results showed that low expression of cytoplasmic BRCA1 and BRCA2 were commonly associated with advanced TNM stage, while high expression of nuclear BRCA1 was generally correlated with advanced tumor stages in these cancers. High expression of cytoplasmic BRCA1 and BRCA2 had significantly favorable overall survival in digestive system cancers; in contrast, BRCA1 nuclear expression usually predicted poor outcomes. We conclude that BRCA1 and BRCA2 could be used as clinicopathological biomarkers to evaluate the prognosis of digestive system cancers. Copyright © 2017. Published by Elsevier Inc.

  5. Refined histopathological predictors of BRCA1 and BRCA2 mutation status

    DEFF Research Database (Denmark)

    Spurdle, Amanda B; Couch, Fergus J; Parsons, Michael T

    2014-01-01

    INTRODUCTION: The distribution of histopathological features of invasive breast tumors in BRCA1 or BRCA2 germline mutation carriers differs from that of individuals with no known mutation. Histopathological features thus have utility for mutation prediction, including statistical modeling to assess...... pathogenicity of BRCA1 or BRCA2 variants of uncertain clinical significance. We analyzed large pathology datasets accrued by the Consortium of Investigators of Modifiers of BRCA1/2 (CIMBA) and the Breast Cancer Association Consortium (BCAC) to reassess histopathological predictors of BRCA1 and BRCA2 mutation...... status, and provide robust likelihood ratio (LR) estimates for statistical modeling. METHODS: Selection criteria for study/center inclusion were estrogen receptor (ER) status or grade data available for invasive breast cancer diagnosed younger than 70 years. The dataset included 4,477 BRCA1 mutation...

  6. Low frequency of large genomic rearrangements of BRCA1 and BRCA2 in western Denmark

    DEFF Research Database (Denmark)

    Thomassen, Mads; Gerdes, Anne-Marie; Cruger, Dorthe

    2006-01-01

    Germline mutations in BRCA1 and BRCA2 predispose female carriers to breast and ovarian cancer. The majority of mutations identified are small deletions or insertions or are nonsense mutations. Large genomic rearrangements in BRCA1 are found with varying frequencies in different populations......, but BRCA2 rearrangements have not been investigated thoroughly. The objective in this study was to determine the frequency of large genomic rearrangements in BRCA1 and BRCA2 in a large group of Danish families with increased risk of breast and ovarian cancer. A total of 617 families previously tested...... negative for mutations involving few bases were screened with multiplex ligation-dependent probe amplification (MLPA). Two deletions in BRCA1 were identified in three families; no large rearrangements were detected in BRCA2. The large deletions constitute 3.8% of the BRCA1 mutations identified, which...

  7. Telomere length shows no association with BRCA1 and BRCA2 mutation status

    DEFF Research Database (Denmark)

    Killick, Emma; Tymrakiewicz, Malgorzata; Cieza-Borrella, Clara

    2014-01-01

    This study aimed to determine whether telomere length (TL) is a marker of cancer risk or genetic status amongst two cohorts of BRCA1 and BRCA2 mutation carriers and controls. The first group was a prospective set of 665 male BRCA1/2 mutation carriers and controls (mean age 53 years), all healthy...... at time of enrollment and blood donation, 21 of whom have developed prostate cancer whilst on study. The second group consisted of 283 female BRCA1/2 mutation carriers and controls (mean age 48 years), half of whom had been diagnosed with breast cancer prior to enrollment. TL was quantified by qPCR from...... DNA extracted from peripheral blood lymphocytes. Weighted and unweighted Cox regressions and linear regression analyses were used to assess whether TL was associated with BRCA1/2 mutation status or cancer risk. We found no evidence for association between developing cancer or being a BRCA1 or BRCA2...

  8. Reproductive and hormonal factors, and ovarian cancer risk for BRCA1 and BRCA2 mutation carriers:

    DEFF Research Database (Denmark)

    Antoniou, Antonis C; Rookus, Matti; Andrieu, Nadine

    2009-01-01

    BACKGROUND: Several reproductive and hormonal factors are known to be associated with ovarian cancer risk in the general population, including parity and oral contraceptive (OC) use. However, their effect on ovarian cancer risk for BRCA1 and BRCA2 mutation carriers has only been investigated...... in a small number of studies. METHODS: We used data on 2,281 BRCA1 carriers and 1,038 BRCA2 carriers from the International BRCA1/2 Carrier Cohort Study to evaluate the effect of reproductive and hormonal factors on ovarian cancer risk for mutation carriers. Data were analyzed within a weighted Cox...... proportional hazards framework. RESULTS: There were no significant differences in the risk of ovarian cancer between parous and nulliparous carriers. For parous BRCA1 mutation carriers, the risk of ovarian cancer was reduced with each additional full-term pregnancy (P trend = 0.002). BRCA1 carriers who had...

  9. RANK ligand as a potential target for breast cancer prevention in BRCA1-mutation carriers.

    Science.gov (United States)

    Nolan, Emma; Vaillant, François; Branstetter, Daniel; Pal, Bhupinder; Giner, Göknur; Whitehead, Lachlan; Lok, Sheau W; Mann, Gregory B; Rohrbach, Kathy; Huang, Li-Ya; Soriano, Rosalia; Smyth, Gordon K; Dougall, William C; Visvader, Jane E; Lindeman, Geoffrey J

    2016-08-01

    Individuals who have mutations in the breast-cancer-susceptibility gene BRCA1 (hereafter referred to as BRCA1-mutation carriers) frequently undergo prophylactic mastectomy to minimize their risk of breast cancer. The identification of an effective prevention therapy therefore remains a 'holy grail' for the field. Precancerous BRCA1(mut/+) tissue harbors an aberrant population of luminal progenitor cells, and deregulated progesterone signaling has been implicated in BRCA1-associated oncogenesis. Coupled with the findings that tumor necrosis factor superfamily member 11 (TNFSF11; also known as RANKL) is a key paracrine effector of progesterone signaling and that RANKL and its receptor TNFRSF11A (also known as RANK) contribute to mammary tumorigenesis, we investigated a role for this pathway in the pre-neoplastic phase of BRCA1-mutation carriers. We identified two subsets of luminal progenitors (RANK(+) and RANK(-)) in histologically normal tissue of BRCA1-mutation carriers and showed that RANK(+) cells are highly proliferative, have grossly aberrant DNA repair and bear a molecular signature similar to that of basal-like breast cancer. These data suggest that RANK(+) and not RANK(-) progenitors are a key target population in these women. Inhibition of RANKL signaling by treatment with denosumab in three-dimensional breast organoids derived from pre-neoplastic BRCA1(mut/+) tissue attenuated progesterone-induced proliferation. Notably, proliferation was markedly reduced in breast biopsies from BRCA1-mutation carriers who were treated with denosumab. Furthermore, inhibition of RANKL in a Brca1-deficient mouse model substantially curtailed mammary tumorigenesis. Taken together, these findings identify a targetable pathway in a putative cell-of-origin population in BRCA1-mutation carriers and implicate RANKL blockade as a promising strategy in the prevention of breast cancer.

  10. The effectiveness of cucurbitacin B in BRCA1 defective breast cancer cells.

    Directory of Open Access Journals (Sweden)

    Moltira Promkan

    Full Text Available Cucurbitacin B (CuB is one of the potential agents for long term anticancer chemoprevention. Cumulative evidences has shown that cucurbitacin B provides potent cellular biological activities such as hepatoprotective, anti-inflammatory and antimicrobial effects, but the precise mechanism of this agent is not clearly understood. We examine the biological effects on cancer cells of cucurbitacin B extracted from a Thai herb, Trichosanthes cucumerina L. The wild type (wt BRCA1, mutant BRCA1, BRCA1 knocked-down and BRCA1 overexpressed breast cancer cells were treated with the cucurbitacin B and determined for the inhibitory effects on the cell proliferation, migration, invasion, anchorage-independent growth. The gene expressions in the treated cells were analyzed for p21/(Waf1, p27(Kip1 and survivin. Our previous study revealed that loss of BRCA1 expression leads to an increase in survivin expression, which is responsible for a reduction in sensitivity to paclitaxel. In this work, we showed that cucurbitacin B obviously inhibited knocked-down and mutant BRCA1 breast cancer cells rather than the wild type BRCA1 breast cancer cells in regards to the cellular proliferation, migration, invasion and anchorage-independent growth. Furthermore, forcing the cells to overexpress wild type BRCA1 significantly reduced effectiveness of cucurbitacin B on growth inhibition of the endogenous mutant BRCA1 cells. Interestingly, cucurbitacin B promotes the expression of p21/(Waf1 and p27(Kip1 but inhibit the expression of survivin. We suggest that survivin could be an important target of cucurbitacin B in BRCA1 defective breast cancer cells.

  11. Induction of ovarian leiomyosarcomas in mice by conditional inactivation of Brca1 and p53.

    Directory of Open Access Journals (Sweden)

    Bridget A Quinn

    2009-12-01

    Full Text Available Approximately one out of every ten cases of epithelial ovarian cancer (EOC is inherited. The majority of inherited cases of EOC result from mutations in the breast cancer associated gene 1 (BRCA1. In addition to mutation of BRCA1, mutation of the p53 gene is often found in patients with inherited breast and ovarian cancer syndrome.We investigated the role of loss of function of BRCA1 and p53 in ovarian cancer development using mouse models with conditionally expressed alleles of Brca1 and/or p53. Our results show that ovary-specific Cre-recombinase-mediated conditional inactivation of both Brca1(LoxP/LoxP and p53(LoxP/LoxP resulted in ovarian or reproductive tract tumor formation in 54% of mice, whereas conditional inactivation of either allele alone infrequently resulted in tumors (< or =5% of mice. In mice with conditionally inactivated Brca1(LoxP/LoxP and p53(LoxP/LoxP, ovarian tumors arose after long latency with the majority exhibiting histological features consistent with high grade leiomyosarcomas lacking expression of epithelial, follicular or lymphocyte markers. In addition, tumors with conditional inactivation of both Brca1(LoxP/LoxP and p53(LoxP/LoxP exhibited greater genomic instability compared to an ovarian tumor with inactivation of only p53(LoxP/LoxP.Although conditional inactivation of both Brca1 and p53 results in ovarian tumorigenesis, our results suggest that additional genetic alterations or alternative methods for targeting epithelial cells of the ovary or fallopian tube for conditional inactivation of Brca1 and p53 are required for the development of a mouse model of Brca1-associated inherited EOC.

  12. Genetic heterogeneity in hereditary breast cancer: Role of BRCA1 and BRCA2

    Energy Technology Data Exchange (ETDEWEB)

    Rebbeck, T.R.; Couch, F.J.; Kant, J. [Univ. of Pennsylvania School of Medicine, Philadelphia, PA (United States)

    1996-09-01

    The common hereditary forms of breast cancer have been largely attributed to the inheritance of mutations in the BRCA1 or BRCA2 genes. However, it is not yet clear what proportion of hereditary breast cancer is explained by BRCA1 and BRCA2 or by some other unidentified susceptibility gene(s). We describe the proportion of hereditary breast cancer explained by BRCA1 or BRCA2 in a sample of North American hereditary breast cancers and assess the evidence for additional susceptibility genes that may confer hereditary breast or ovarian cancer risk. Twenty-three families were identified through two high-risk breast cancer research programs. Genetic analysis was undertaken to establish linkage between the breast or ovarian cancer cases and markers on chromosomes 17q (BRCA1) and 13q (BRCA2). Mutation analysis in the BRCA1 and BRCA2 genes was also undertaken in all families. The pattern of hereditary cancer in 14 (61%) of the 23 families studied was attributed to BRCA1 by a combination of linkage and mutation analyses. No families were attributed to BRCA2. Five families (22%) provided evidence against linkage to both BRCA1 and BRCA2. No BRCA1 or BRCA2 mutations were detected in these five families. The BRCA1 or BRCA2 status of four families (17%) could not be determined. BRCA1 and BRCA2 probably explain the majority of hereditary breast cancer that exists in the North American population. However, one or more additional genes may yet be found that explain some proportion of hereditary breast cancer. 19 refs., 1 fig., 3 tabs.

  13. Thyroid Hormone Receptors Predict Prognosis in BRCA1 Associated Breast Cancer in Opposing Ways

    Science.gov (United States)

    Heublein, Sabine; Mayr, Doris; Meindl, Alfons; Angele, Martin; Gallwas, Julia; Jeschke, Udo; Ditsch, Nina

    2015-01-01

    Since BRCA1 associated breast cancers are frequently classified as hormone receptor negative or even triple negative, the application of endocrine therapies is rather limited in these patients. Like hormone receptors that bind to estrogen or progesterone, thyroid hormone receptors (TRs) are members of the nuclear hormone receptor superfamily. TRs might be interesting biomarkers - especially in the absence of classical hormone receptors. The current study aimed to investigate whether TRs may be specifically expressed in BRCA1 associated cancer cases and whether they are of prognostic significance in these patients as compared to sporadic breast cancer cases. This study analyzed TRα and TRβ immunopositivity in BRCA1 associated (n = 38) and sporadic breast cancer (n = 86). Further, TRs were studied in MCF7 (BRCA1 wildtype) and HCC3153 (BRCA1 mutated) cells. TRβ positivity rate was significantly higher in BRCA1 associated as compared to sporadic breast cancers (p = 0.001). The latter observation remained to be significant when cases that had been matched for clinicopathological criteria were compared (p = 0.037). Regarding BRCA1 associated breast cancer cases TRβ positivity turned out to be a positive prognostic factor for five-year (p = 0.007) and overall survival (p = 0.026) while TRα positivity predicted reduced five-year survival (p = 0.030). Activation of TRβ resulted in down-modulation of CTNNB1 while TRα inhibition reduced cell viability in HCC3153. However, only BRCA1 wildtype MCF7 cells were capable of rapidly degrading TRα1 in response to T3 stimulation. Significantly, this study identified TRβ to be up-regulated in BRCA1 associated breast cancer and revealed TRs to be associated with patients’ prognosis. TRs were also found to be expressed in triple negative BRCA1 associated breast cancer. Further studies need to be done in order to evaluate whether TRs may become interesting targets of endocrine therapeutic approaches, especially when tumors are

  14. Thyroid Hormone Receptors Predict Prognosis in BRCA1 Associated Breast Cancer in Opposing Ways.

    Directory of Open Access Journals (Sweden)

    Sabine Heublein

    Full Text Available Since BRCA1 associated breast cancers are frequently classified as hormone receptor negative or even triple negative, the application of endocrine therapies is rather limited in these patients. Like hormone receptors that bind to estrogen or progesterone, thyroid hormone receptors (TRs are members of the nuclear hormone receptor superfamily. TRs might be interesting biomarkers - especially in the absence of classical hormone receptors. The current study aimed to investigate whether TRs may be specifically expressed in BRCA1 associated cancer cases and whether they are of prognostic significance in these patients as compared to sporadic breast cancer cases. This study analyzed TRα and TRβ immunopositivity in BRCA1 associated (n = 38 and sporadic breast cancer (n = 86. Further, TRs were studied in MCF7 (BRCA1 wildtype and HCC3153 (BRCA1 mutated cells. TRβ positivity rate was significantly higher in BRCA1 associated as compared to sporadic breast cancers (p = 0.001. The latter observation remained to be significant when cases that had been matched for clinicopathological criteria were compared (p = 0.037. Regarding BRCA1 associated breast cancer cases TRβ positivity turned out to be a positive prognostic factor for five-year (p = 0.007 and overall survival (p = 0.026 while TRα positivity predicted reduced five-year survival (p = 0.030. Activation of TRβ resulted in down-modulation of CTNNB1 while TRα inhibition reduced cell viability in HCC3153. However, only BRCA1 wildtype MCF7 cells were capable of rapidly degrading TRα1 in response to T3 stimulation. Significantly, this study identified TRβ to be up-regulated in BRCA1 associated breast cancer and revealed TRs to be associated with patients' prognosis. TRs were also found to be expressed in triple negative BRCA1 associated breast cancer. Further studies need to be done in order to evaluate whether TRs may become interesting targets of endocrine therapeutic approaches, especially when

  15. Detección de aneuploidías del cromosoma 17 y deleción del gen TP53 en una amplia variedad de tumores sólidos mediante hibridación in situ fluorescente bicolor

    Directory of Open Access Journals (Sweden)

    Juan Carlos Herrera

    2010-09-01

    Conclusiones. La aneuploidía del cromosoma 17 y la deleción en el locus 17p13.1 del gen TP53 son alteraciones muy frecuentes en los tumores sólidos. La técnica FISH-bicolor permite detectar simultáneamente alteraciones cromosómicas numéricas y estructurales en núcleos interfásicos.

  16. Expression of proapoptotic BAX and TP53 genes and antiapoptotic BCL-2 gene in MCF-7 and T-47D tumour cell cultures of the mammary gland after a photodynamic therapy with photolon.

    Science.gov (United States)

    Płonka, Justyna; Latocha, Małgorzata; Kuśmierz, Dariusz; Zielińska, Aleksandra

    2015-01-01

    Breast cancer is the most common malignant tumour in women in the whole world. Despite significant developments in the early diagnosis of breast cancer, there is no effective method which would assure total recovery of the patient. Currently available clinical data and laboratory tests indicate a possibility to introduce photodynamic therapy (PDT) to the supplementary treatment of breast cancer. The aim of this study was to assess the influence of PDT with Photolon as a photosensibilizator on the expression of apoptosis associated genes (BCL-2, BAX, TP53) in human breast cancer cell lines, preceded by assessment of survivorship and proliferative activity in the tested cells after PDT. In the present study human breast cancer cell lines MCF-7 and T-47D were used. Photolon (chlorin e6 complex: PVP 1:1) was used as a photosensitizer. Assessments of survivorship and proliferative activity of cells under the influence of PDT (WST-1 test) were conducted along with the expression of selected genes involved in the process of apoptosis: BCL-2, BAX, TP53 (RT-QPCR). PDT limited both survivorship and proliferative activity of breast cancer cells in the two tested lines. In case of T-47D cell line was found increase of BAX and BCL-2 genes expression after PDT and sustained activity of TP53 gene. Conversely, in MCF-7 cell line a decrease in expression was found for both BAX and TP53 genes, but also an increase of BCL-2 gene expression. A progressing decrease (24, 48 and 72 h after PDT) in the count of culture cells, which suggests the occurrence of apoptosis initiated by a photodynamic reaction with simultaneous increase of BCL-2/BAX index, indicates activation of a different endogenous apoptosis pathway than the one examined, namely pointing to suicidal death of cells after PDT.

  17. Pathology of breast and ovarian cancers among BRCA1 and BRCA2 mutation carriers: results from the Consortium of Investigators of Modifiers of BRCA1/2 (CIMBA)

    Science.gov (United States)

    Mavaddat, Nasim; Barrowdale, Daniel; Andrulis, Irene L.; Domchek, Susan M.; Eccles, Diana; Nevanlinna, Heli; Ramus, Susan J.; Spurdle, Amanda; Robson, Mark; Sherman, Mark; Mulligan, Anna Marie; Couch, Fergus J.; Engel, Christoph; McGuffog, Lesley; Healey, Sue; Sinilnikova, Olga M.; Southey, Melissa C.; Terry, Mary Beth; Goldgar, David; O’Malley, Frances; John, Esther M.; Janavicius, Ramunas; Tihomirova, Laima; Hansen, Thomas v O; Nielsen, Finn C.; Osorio, Ana; Stavropoulou, Alexandra; Benítez, Javier; Manoukian, Siranoush; Peissel, Bernard; Barile, Monica; Volorio, Sara; Pasini, Barbara; Dolcetti, Riccardo; Putignano, Anna Laura; Ottini, Laura; Radice, Paolo; Hamann, Ute; Rashid, Muhammad U.; Hogervorst, Frans B.; Kriege, Mieke; van der Luijt, Rob B.; Peock, Susan; Frost, Debra; Evans, D. Gareth; Brewer, Carole; Walker, Lisa; Rogers, Mark T.; Side, Lucy E.; Houghton, Catherine; Weaver, JoEllen; Godwin, Andrew K.; Schmutzler, Rita K.; Wappenschmidt, Barbara; Meindl, Alfons; Kast, Karin; Arnold, Norbert; Niederacher, Dieter; Sutter, Christian; Deissler, Helmut; Gadzicki, Doroteha; Preisler-Adams, Sabine; Varon-Mateeva, Raymonda; Schönbuchner, Ines; Gevensleben, Heidrun; Stoppa-Lyonnet, Dominique; Belotti, Muriel; Barjhoux, Laure; Isaacs, Claudine; Peshkin, Beth N.; Caldes, Trinidad; de al Hoya, Miguel; Cañadas, Carmen; Heikkinen, Tuomas; Heikkilä, Päivi; Aittomäki, Kristiina; Blanco, Ignacio; Lazaro, Conxi; Brunet, Joan; Agnarsson, Bjarni A.; Arason, Adalgeir; Barkardottir, Rosa B.; Dumont, Martine; Simard, Jacques; Montagna, Marco; Agata, Simona; D’Andrea, Emma; Yan, Max; Fox, Stephen; Rebbeck, Timothy R.; Rubinstein, Wendy; Tung, Nadine; Garber, Judy E.; Wang, Xianshu; Fredericksen, Zachary; Pankratz, Vernon S.; Lindor, Noralane M.; Szabo, Csilla; Offit, Kenneth; Sakr, Rita; Gaudet, Mia M.; Singer, Christian F.; Tea, Muy-Kheng; Rappaport, Christine; Mai, Phuong L.; Greene, Mark H.; Sokolenko, Anna; Imyanitov, Evgeny; Toland, Amanda Ewart; Senter, Leigha; Sweet, Kevin; Thomassen, Mads; Gerdes, Anne-Marie; Kruse, Torben; Caligo, Maria; Aretini, Paolo; Rantala, Johanna; von Wachenfeld, Anna; Henriksson, Karin; Steele, Linda; Neuhausen, Susan L.; Nussbaum, Bob; Beattie, Mary; Odunsi, Kunle; Sucheston, Lara; Gayther, Simon A; Nathanson, Kate; Gross, Jenny; Walsh, Christine; Karlan, Beth; Chenevix-Trench, Georgia; Easton, Douglas F.; Antoniou, Antonis C.

    2011-01-01

    Background Previous small studies found that BRCA1 and BRCA2 breast tumors differ in their pathology. Analysis of larger datasets of mutation carriers should allow further tumor characterization. Methods We used data from 4,325 BRCA1 and 2,568 BRCA2 mutation carriers to analyze the pathology of invasive breast, ovarian and contralateral breast cancers. Results There was strong evidence that the proportion of estrogen receptor (ER)-negative breast tumors decreased with age at diagnosis among BRCA1 (p-trend=1.2×10−5) but increased with age at diagnosis among BRCA2 carriers (p-trend=6.8×10−6). The proportion of triple negative tumors decreased with age at diagnosis in BRCA1 carriers but increased with age at diagnosis of BRCA2 carriers. In both BRCA1 and BRCA2 carriers, ER-negative tumors were of higher histological grade than ER-positive tumors (Grade 3 vs. Grade 1, p=1.2×10−13 for BRCA1 and p=0.001 for BRCA2). ER and progesterone receptor (PR) expression were independently associated with mutation carrier status (ER-positive odds ratio (OR) for BRCA2=9.4, 95%CI:7.0-12.6 and PR-positive OR=1.7, 95%CI:1.3-2.3, under joint analysis). Lobular tumors were more likely to be BRCA2-related (OR for BRCA2=3.3, 95%CI:2.4-4.4, p=4.4×10−14), and medullary tumors BRCA1-related (OR for BRCA2=0.25, 95%CI:0.18-0.35, p=2.3×10−15). ER-status of the first breast cancer was predictive of ER-status of asynchronous contralateral breast cancer (p=0.0004 for BRCA1; p=0.002 for BRCA2). There were no significant differences in ovarian cancer morphology between BRCA1 and BRCA2 carriers (serous:67%; mucinous:1%; endometriod:12%; clear-cell:2%). Conclusions/Impact Pathology characteristics of BRCA1 and BRCA2 tumors may be useful for improving risk prediction algorithms and informing clinical strategies for screening and prophylaxis. PMID:22144499

  18. Large genomic rearrangements of BRCA1 and BRCA2 among patients referred for genetic analysis in Galicia (NW Spain): delimitation and mechanism of three novel BRCA1 rearrangements.

    Science.gov (United States)

    Fachal, Laura; Blanco, Ana; Santamariña, Marta; Carracedo, Angel; Vega, Ana

    2014-01-01

    In the Iberian Peninsula, which includes mainly Spain and Portugal, large genomic rearrangements (LGRs) of BRCA1 and BRCA2 have respectively been found in up to 2.33% and 8.4% of families with hereditary breast and/or ovarian cancer (HBOC) that lack point mutations and small indels. In Galicia (Northwest Spain), the spectrum and frequency of BRCA1/BRCA2 point mutations differs from the rest of the Iberian populations. However, to date there are no Galician frequency reports of BRCA1/BRCA2 LGRs. Here we used multiplex ligation-dependent probe amplification (MLPA) to screen 651 Galician index cases (out of the 830 individuals referred for genetic analysis) without point mutations or small indels. We identified three different BRCA1 LGRs in four families. Two of them have been previously classified as pathogenic LGRs: the complete deletion of BRCA1 (identified in two unrelated families) and the deletion of exons 1 to 13. We also identified the duplication of exons 1 and 2 that is a LGR with unknown pathogenicity. Determination of the breakpoints of the BRCA1 LGRs using CNV/SNP arrays and sequencing identified them as NG_005905.2:g.70536_180359del, NG_005905.2:g.90012_97270dup, and NC_000017.10:g.41230935_41399840delinsAluSx1, respectively; previous observations of BRCA1 exon1-24del, exon1-2dup, and exon1-13del LGRs have not characterized them in such detail. All the BRCA1 LGRs arose from unequal homologous recombination events involving Alu elements. We also detected, by sequencing, one BRCA2 LGR, the Portuguese founder mutation c.156_157insAluYa5. The low frequency of BRCA1 LGRs within BRCA1 mutation carriers in Galicia (2.34%, 95% CI: 0.61-7.22) seems to differ from the Spanish population (9.93%, 95% CI: 6.76-14.27, P-value = 0.013) and from the rest of the Iberian population (9.76%, 95% CI: 6.69-13.94, P-value = 0.014).

  19. Alterations in TP53, cyclin D2, c-Myc, p21WAF1/CIP1 and p27KIP1 expression associated with progression in B-CLL

    Directory of Open Access Journals (Sweden)

    Antosz Halina

    2010-04-01

    Full Text Available B-cell chronic lymphocytic leukaemia (B-CLL originates from B lymphocytes that may differ in the activationlevel, maturation state or cellular subgroups in peripheral blood. Tumour progression in CLL B cells seems to result in gradualaccumulation of the clone of resting B lymphocytes in the early phases (G0/G1 of the cell cycle. The G1 phase isimpaired in B-CLL. We investigated the gene expression of five key cell cycle regulators: TP 53, c-Myc, cyclin D2,p21WAF1/CIP1 and p27KIP1, which primarily regulate the G1 phase of the cell cycle, or S-phase entry and ultimately controlthe proliferation and cell growth as well as their role in B-CLL progression. The study was conducted in peripheral bloodCLL lymphocytes of 40 previously untreated patients. Statistical analysis of correlations of TP53, cyclin D2, c-Myc,p21WAF1/CIP1 and p27KIP1 expressions in B-CLL patients with different Rai stages demonstrated that the progression of diseasewas accompanied by increases in p53, cyclin D2 and c-Myc mRNA expression. The expression of p27KIP1 was nearlystatistically significant whereas that of p21 WAF1/CIP1 showed no such correlation. Moreover, high expression levels of TP53and c-Myc genes were found to be closely associated with more aggressive forms of the disease requiring earlier therapy.

  20. Induction of apoptosis through ER stress and TP53 in MCF-7 cells by the nanoparticle [Gd@C82(OH)22]n: A systems biology study.

    Science.gov (United States)

    Wang, Lin; Meng, Jie; Cao, Weipeng; Li, Qizhai; Qiu, Yuqing; Sun, Baoyun; Li, Lei M

    2014-06-01

    those of HEK293T and MCF-7 cells induced by the miR-23a∼27a∼24-2 cluster. Furthermore, one of the inferred regulatory mechanisms comprises the apoptosis network centered around TP53, whose effective regulation of apoptosis is somehow reestablished after [Gd@C82(OH)22]n treatment. These results elucidate the application and development of [Gd@C82(OH)22]n and other fullerene derivates. Copyright © 2014 Elsevier Inc. All rights reserved.

  1. Common genetic variation at BARD1 is not associated with breast cancer risk in BRCA1 or BRCA2 mutation carriers

    DEFF Research Database (Denmark)

    Spurdle, Amanda B; Marquart, Louise; McGuffog, Lesley

    2011-01-01

    Inherited BRCA1 and BRCA2 (BRCA1/2) mutations confer elevated breast cancer risk. Knowledge of factors that can improve breast cancer risk assessment in BRCA1/2 mutation carriers may improve personalized cancer prevention strategies.......Inherited BRCA1 and BRCA2 (BRCA1/2) mutations confer elevated breast cancer risk. Knowledge of factors that can improve breast cancer risk assessment in BRCA1/2 mutation carriers may improve personalized cancer prevention strategies....

  2. Association of type and location of BRCA1 and BRCA2 mutations with risk of breast and ovarian cancer

    DEFF Research Database (Denmark)

    Rebbeck, Timothy R; Mitra, Nandita; Wan, Fei

    2015-01-01

    IMPORTANCE: Limited information about the relationship between specific mutations in BRCA1 or BRCA2 (BRCA1/2) and cancer risk exists. OBJECTIVE: To identify mutation-specific cancer risks for carriers of BRCA1/2. DESIGN, SETTING, AND PARTICIPANTS: Observational study of women who were ascertained...

  3. Age at menarche and menopause and breast cancer risk in the International BRCA1/2 Carrier Cohort Study.

    NARCIS (Netherlands)

    Chang-Claude, J.; Andrieu, N.; Rookus, M.A.; Brohet, R.M.; Antoniou, A.C.; Peock, S.; Davidson, R.; Izatt, L.; Cole, T.; Nogues, C.; Luporsi, E.; Huiart, L.; Hoogerbrugge, N.; Leeuwen, F.E. van; Osorio, A.; Eyfjord, J.; Radice, P.; Goldgar, D.E.; Easton, D.F.

    2007-01-01

    BACKGROUND: Early menarche and late menopause are important risk factors for breast cancer, but their effects on breast cancer risk in BRCA1 and BRCA2 carriers are unknown. METHODS: We assessed breast cancer risk in a large series of 1,187 BRCA1 and 414 BRCA2 carriers from the International BRCA1/2

  4. BRCA1-like signature in triple negative breast cancer : Molecular and clinical characterization reveals subgroups with therapeutic potential

    NARCIS (Netherlands)

    Severson, Tesa M; Peeters, Justine; Majewski, Ian; Michaut, Magali; Bosma, Astrid; Schouten, Philip C; Chin, Suet-Feung; Pereira, Bernard; Goldgraben, Mae A; Bismeijer, Tycho; Kluin, Roelof J C; Muris, Jettie J F; Jirström, Karin; Kerkhoven, Ron M; Wessels, Lodewyk; Caldas, Carlos; Bernards, René; Simon, Iris M; Linn, S.C.

    2015-01-01

    Triple negative (TN) breast cancers make up some 15% of all breast cancers. Approximately 10-15% are mutant for the tumor suppressor, BRCA1. BRCA1 is required for homologous recombination-mediated DNA repair and deficiency results in genomic instability. BRCA1-mutated tumors have a specific pattern

  5. BRCA1 R1699Q variant displaying ambiguous functional abrogation confers intermediate breast and ovarian cancer risk

    DEFF Research Database (Denmark)

    Spurdle, Amanda B; Whiley, Phillip J; Thompson, Bryony

    2012-01-01

    Clinical classification of rare sequence changes identified in the breast cancer susceptibility genes BRCA1 and BRCA2 is essential for appropriate genetic counselling of individuals carrying these variants. We previously showed that variant BRCA1 c.5096G>A p.Arg1699Gln in the BRCA1 transcriptional...

  6. Prediction of Breast and Prostate Cancer Risks in Male BRCA1 and BRCA2 Mutation Carriers Using Polygenic Risk Scores

    DEFF Research Database (Denmark)

    Lecarpentier, Julie; Silvestri, Valentina; Kuchenbaecker, Karoline B

    2017-01-01

    for male carriers of BRCA1/ 2 mutations and implications for cancer risk prediction. Materials and Methods We genotyped 1,802 male carriers of BRCA1/2 mutations from the Consortium of Investigators of Modifiers of BRCA1/2 by using the custom Illumina OncoArray. We investigated the combined effects...

  7. Association of Type and Location of BRCA1 and BRCA2 Mutations With Risk of Breast and Ovarian Cancer

    NARCIS (Netherlands)

    Rebbeck, Timothy R.; Mitra, Nandita; Wan, Fei; Sinilnikova, Olga M.; Healey, Sue; McGuffog, Lesley; Mazoyer, Sylvie; Chenevix-Trench, Georgia; Easton, Douglas F.; Antoniou, Antonis C.; Nathanson, Katherine L.; Laitman, Yael; Kushnir, Anya; Paluch-Shimon, Shani; Berger, Raanan; Zidan, Jamal; Friedman, Eitan; Ehrencrona, Hans; Stenmark-Askmalm, Marie; Einbeigi, Zakaria; Loman, Niklas; Harbst, Katja; Rantala, Johanna; Melin, Beatrice; Huo, Dezheng; Olopade, Olufunmilayo I.; Seldon, Joyce; Ganz, Patricia A.; Nussbaum, Robert L.; Chan, Salina B.; Odunsi, Kunle; Gayther, Simon A.; Domchek, Susan M.; Arun, Banu K.; Lu, Karen H.; Mitchell, Gillian; Karlan, Beth Y.; Walsh, Christine; Lester, Jenny; Godwin, Andrew K.; Pathak, Harsh; Ross, Eric; Daly, Mary B.; Whittemore, Alice S.; John, Esther M.; Miron, Alexander; Terry, Mary Beth; Chung, Wendy K.; Goldgar, David E.; Buys, Saundra S.; Janavicius, Ramunas; Tihomirova, Laima; Tung, Nadine; Dorfling, Cecilia M.; van Rensburg, Elizabeth J.; Steele, Linda; Neuhausen, Susan L.; Ding, Yuan Chun; Ejlertsen, Bent; Gerdes, Anne-Marie; Hansen, Thomas v O.; Ramón Y Cajal, Teresa; Osorio, Ana; Benitez, Javier; Godino, Javier; Tejada, Maria-Isabel; Duran, Mercedes; Weitzel, Jeffrey N.; Bobolis, Kristie A.; Sand, Sharon R.; Fontaine, Annette; Savarese, Antonella; Pasini, Barbara; Peissel, Bernard; Bonanni, Bernardo; Zaffaroni, Daniela; Vignolo-Lutati, Francesca; Scuvera, Giulietta; Giannini, Giuseppe; Bernard, Loris; Genuardi, Maurizio; Radice, Paolo; Dolcetti, Riccardo; Manoukian, Siranoush; Pensotti, Valeria; Gismondi, Viviana; Yannoukakos, Drakoulis; Fostira, Florentia; Garber, Judy; Torres, Diana; Rashid, Muhammad Usman; Hamann, Ute; Peock, Susan; Frost, Debra; Platte, Radka; Evans, D. Gareth; Eeles, Rosalind; Davidson, Rosemarie; Eccles, Diana; Cole, Trevor; Cook, Jackie; Brewer, Carole; Hodgson, Shirley; Morrison, Patrick J.; Walker, Lisa; Porteous, Mary E.; Kennedy, M. John; Izatt, Louise; Adlard, Julian; Donaldson, Alan; Ellis, Steve; Sharma, Priyanka; Schmutzler, Rita Katharina; Wappenschmidt, Barbara; Becker, Alexandra; Rhiem, Kerstin; Hahnen, Eric; Engel, Christoph; Meindl, Alfons; Engert, Stefanie; Ditsch, Nina; Arnold, Norbert; Plendl, Hans Jörg; Mundhenke, Christoph; Niederacher, Dieter; Fleisch, Markus; Sutter, Christian; Bartram, C. R.; Dikow, Nicola; Wang-Gohrke, Shan; Gadzicki, Dorothea; Steinemann, Doris; Kast, Karin; Beer, Marit; Varon-Mateeva, Raymonda; Gehrig, Andrea; Weber, Bernhard H.; Stoppa-Lyonnet, Dominique; Houdayer, Claude; Belotti, Muriel; Gauthier-Villars, Marion; Damiola, Francesca; Boutry-Kryza, Nadia; Lasset, Christine; Sobol, Hagay; Peyrat, Jean-Philippe; Muller, Danièle; Fricker, Jean-Pierre; Collonge-Rame, Marie-Agnès; Mortemousque, Isabelle; Nogues, Catherine; Rouleau, Etienne; Isaacs, Claudine; de Paepe, Anne; Poppe, Bruce; Claes, Kathleen; de Leeneer, Kim; Piedmonte, Marion; Rodriguez, Gustavo; Wakely, Katie; Boggess, John; Blank, Stephanie V.; Basil, Jack; Azodi, Masoud; Phillips, Kelly-Anne; Caldes, Trinidad; de la Hoya, Miguel; Romero, Atocha; Nevanlinna, Heli; Aittomäki, Kristiina; van der Hout, Annemarie H.; Hogervorst, Frans B. L.; Verhoef, Senno; Collée, J. Margriet; Seynaeve, Caroline; Oosterwijk, Jan C.; Gille, Johannes J. P.; Wijnen, Juul T.; Gómez Garcia, Encarna B.; Kets, Carolien M.; Ausems, Margreet G. E. M.; Aalfs, Cora M.; Devilee, Peter; Mensenkamp, Arjen R.; Kwong, Ava; Olah, Edith; Papp, Janos; Diez, Orland; Lazaro, Conxi; Darder, Esther; Blanco, Ignacio; Salinas, Mónica; Jakubowska, Anna; Lubinski, Jan; Gronwald, Jacek; Jaworska-Bieniek, Katarzyna; Durda, Katarzyna; Sukiennicki, Grzegorz; Huzarski, Tomasz; Byrski, Tomasz; Cybulski, Cezary; Toloczko-Grabarek, Aleksandra; Złowocka-Perłowska, Elżbieta; Menkiszak, Janusz; Arason, Adalgeir; Barkardottir, Rosa B.; Simard, Jacques; Laframboise, Rachel; Montagna, Marco; Agata, Simona; Alducci, Elisa; Peixoto, Ana; Teixeira, Manuel R.; Spurdle, Amanda B.; Lee, Min Hyuk; Park, Sue K.; Kim, Sung-Won; Friebel, Tara M.; Couch, Fergus J.; Lindor, Noralane M.; Pankratz, Vernon S.; Guidugli, Lucia; Wang, Xianshu; Tischkowitz, Marc; Foretova, Lenka; Vijai, Joseph; Offit, Kenneth; Robson, Mark; Rau-Murthy, Rohini; Kauff, Noah; Fink-Retter, Anneliese; Singer, Christian F.; Rappaport, Christine; Gschwantler-Kaulich, Daphne; Pfeiler, Georg; tea, Muy-Kheng; Berger, Andreas; Greene, Mark H.; Mai, Phuong L.; Imyanitov, Evgeny N.; Toland, Amanda Ewart; Senter, Leigha; Bojesen, Anders; Pedersen, Inge Sokilde; Skytte, Anne-Bine; Sunde, Lone; Thomassen, Mads; Moeller, Sanne Traasdahl; Kruse, Torben A.; Jensen, Uffe Birk; Caligo, Maria Adelaide; Aretini, Paolo; teo, Soo-Hwang; Selkirk, Christina G.; Hulick, Peter J.; Andrulis, Irene

    2015-01-01

    IMPORTANCE Limited information about the relationship between specific mutations in BRCA1 or BRCA2 (BRCA1/2) and cancer risk exists. OBJECTIVE To identify mutation-specific cancer risks for carriers of BRCA1/2. DESIGN, SETTING, AND PARTICIPANTS Observational study of women who were ascertained

  8. Association of type and location of BRCA1 and BRCA2 mutations with risk of breast and ovarian cancer

    NARCIS (Netherlands)

    R. Rebbeck (Timothy); N. Mitra (Nandita); F. Wan (Fei); O. Sinilnikova (Olga); S. Healey (Sue); L. McGuffog (Lesley); G. Chenevix-Trench (Georgia); D.F. Easton (Douglas); A.C. Antoniou (Antonis C.); K.L. Nathanson (Katherine); Y. Laitman (Yael); A. Kushnir (Anya); S. Paluch-Shimon (Shani); R. Berger (Raanan); J. Zidan (Jamal); E. Friedman (Eitan); H. Ehrencrona (Hans); M. Stenmark-Askmalm (Marie); Z. Einbeigi (Zakaria); N. Loman (Niklas); K. Harbst (Katja); J. Rantala (Johanna); B. Melin (Beatrice); D. Huo (Dezheng); O.I. Olopade (Olofunmilayo); J.L. Seldon (Joyce); P.A. Ganz (Patricia); R.L. Nussbaum (Robert L.); S. Chan (Salina); K. Odunsi (Kunle); S.A. Gayther (Simon); S.M. Domchek (Susan); B.K. Arun (Banu); K.H. Lu (Karen); G. Mitchell (Gillian); B. Karlan; C.S. Walsh (Christine); K.J. Lester (Kathryn); A.K. Godwin (Andrew); S.S. Pathak; E.B. Ross (Eric); M.J. Daly (Mark); A.S. Whittemore (Alice); E.M. John (Esther); A. Miron (Alexander); M.B. Terry (Mary Beth); W.K. Chung (Wendy K.); D. Goldgar (David); S.S. Buys (Saundra); R. Janavicius (Ramunas); L. Tihomirova (Laima); N. Tung (Nadine); C.M. Dorfling (Cecilia); E.J. van Rensburg (Elizabeth); L. Steele (Linda); S.L. Neuhausen (Susan); Y.C. Ding (Yuan); B. Ejlertsen (Bent); A-M. Gerdes (Anne-Marie); T.V.O. Hansen (Thomas); T. Ramon Y Cajal; A. Osorio (Ana); J. Benítez (Javier); J. Godino (Javier); M.I. Tejada; M. Duran (Mercedes); J.N. Weitzel (Jeffrey); K.A. Bobolis (Kristie A.); S.R. Sand (Sharon); A. Fontaine (Annette); A. Savarese (Antonella); B. Pasini (Barbara); B. Peissel (Bernard); B. Bonnani (Bernardo); D. Zaffaroni (Daniela); F. Vignolo-Lutati (Francesca); G. Scuvera (Giulietta); G. Giannini (Giuseppe); L. Bernard (Loris); M. Genuardi (Maurizio); P. Radice (Paolo); R. Dolcetti (Riccardo); S. Manoukian (Siranoush); V. Pensotti (Valeria); V. Gismondi (Viviana); D. Yannoukakos (Drakoulis); F. Fostira (Florentia); J. Garber (Judy); D. Torres (Diana); M.U. Rashid (Muhammad); U. Hamann (Ute); S. Peock (Susan); D. Frost (Debra); R. Platte (Radka); D.G. Evans (Gareth); R. Eeles (Rosalind); R. Davidson (Rosemarie); D. Eccles (Diana); T. Cole (Trevor); J. Cook (Jackie); C. Brewer (Carole); S. Hodgson (Shirley); P.J. Morrison (Patrick); L.J. Walker (Lisa); M.E. Porteous (Mary); M.J. Kennedy (John); L. Izatt (Louise); L. Adlard; A. Donaldson (Alan); S.D. Ellis (Steve); P. Sharma (Priyanka); R.K. Schmutzler (Rita); B. Wapenschmidt (Barbara); A. Becker (Alexandra); K. Rhiem (Kerstin); E. Hahnen (Eric); C.W. Engel (Christoph); A. Meindl (Alfons); S. Engert (Stefanie); N. Ditsch (Nina); N. Arnold (Norbert); H. Plendl (Hansjoerg); C. Mundhenke (Christoph); D. Niederacher (Dieter); M.C. Fleisch (Markus); C. Sutter (Christian); C.R. Bartram; N. Dikow (Nicola); S. Wang-Gohrke (Shan); D. Gadzicki (Dorothea); D. Steinemann (Doris); K. Kast (Karin); M. Beer (Marit); R. Varon-Mateeva (Raymonda); P.A. Gehrig (Paola A.); B.H.F. Weber (Bernhard); D. Stoppa-Lyonnet (Dominique); M. Belotti (Muriel); M. Gauthier-Villars (Marion); F. Damiola (Francesca); N. Boutry-Kryza (N.); C. Lasset (Christine); H. Sobol (Hagay); J.-P. Peyrat; D.W. Muller (Danièle); J.P. Fricker (Jean Pierre); M.-A. Collonge-Rame; I. Mortemousque (Isabelle); C. Nogues (Catherine); E. Rouleau (Etienne); C. Isaacs (Claudine); A. de Paepe (Anne); B. Poppe (Bruce); K. Claes (Kathleen); K. De Leeneer (Kim); M. Piedmonte (Marion); G. Rodriguez (Gustavo); K. Wakely (Katie); J.F. Boggess (John); S.V. Blank (Stephanie); J. Basil (Jack); M. Azodi (Masoud); K.-A. Phillips (Kelly-Anne); T. Caldes (Trinidad); M. de La Hoya (Miguel); A. Romero (Atocha); H. Nevanlinna (Heli); K. Aittomäki (Kristiina); A.H. van der Hout (Annemarie); F.B.L. Hogervorst (Frans); S. Verhoef; J.M. Collee (Margriet); C.M. Seynaeve (Caroline); J.C. Oosterwijk (Jan); J.J. Gille (Johan); J.T. Wijnen (Juul); E.B. Gómez García (Encarna); C.M. Kets; M.G.E.M. Ausems (Margreet); C.M. Aalfs (Cora); P. Devilee (Peter); A.R. Mensenkamp (Arjen); A. Kwong (Ava); E. Olah; J. Papp (Janos); O. Díez (Orland); C. Lazaro (Conxi); E. Darder (Esther); I. Blanco (Ignacio); M. Salinas; A. Jakubowska (Anna); J. Lubinski (Jan); J. Gronwald (Jacek); K. Jaworska-Bieniek (Katarzyna); K. Durda (Katarzyna); G. Sukiennicki (Grzegorz); T. Huzarski (Tomasz); T. Byrski (Tomasz); C. Cybulski (Cezary); A. Toloczko-Grabarek (Aleksandra); E. Złowocka-Perłowska (Elzbieta); J. Menkiszak (Janusz); A. Arason (Adalgeir); R.B. Barkardottir (Rosa); J. Simard (Jacques); R. Laframboise (Rachel); M. Montagna (Marco); S. Agata (Simona); E. Alducci (Elisa); A. Peixoto (Ana); P.J. Teixeira; A.B. Spurdle (Amanda); M.H. Lee (Min Hyuk); S.K. Park (Sue); S.-W. Kim (Sung-Won); M.O.W. Friebel (Mark ); F.J. Couch (Fergus); N.M. Lindor (Noralane); V.S. Pankratz (Shane); L. Guidugli (Lucia); X. Wang (Xianshu); M. Tischkowitz (Marc); L. Foretova (Lenka); J. Vijai (Joseph); K. Offit (Kenneth); M. Robson (Mark); R. Rau-Murthy (Rohini); N. Kauff (Noah); A. Fink-Retter (Anneliese); C.F. Singer (Christian); C. Rappaport (Christine); D. Gschwantler-Kaulich (Daphne); G. Pfeiler (Georg); M.-K. Tea; A. Berger (Andreas); M.H. Greene (Mark); P.L. Mai (Phuong); E.N. Imyanitov (Evgeny); A.E. Toland (Amanda); L. Senter (Leigha); A. Bojesen (Anders); I.S. Pedersen (Inge Sokilde); A.-B. Skytte (Anne-Bine); L. Sunde (Lone); M. Thomassen (Mads); S.T. Moeller (Sanne Traasdahl); T.A. Kruse (Torben); U.B. Jensen; M.A. Caligo (Maria); P. Aretini (Paolo); S.-H. Teo; C.G. Selkirk (Christina); P.J. Hulick (Peter); I.L. Andrulis (Irene)

    2015-01-01

    textabstractImportance: Limited information about the relationship between specific mutations in BRCA1 or BRCA2 (BRCA1/2) and cancer risk exists. Objective: To identify mutation-specific cancer risks for carriers of BRCA1/2. Design, Setting, and Participants: Observational study ofwomen whowere

  9. BRCA1 contributes to cell cycle arrest and chemoresistance in response to the anticancer agent irofulven.

    Science.gov (United States)

    Wiltshire, Timothy; Senft, Jamie; Wang, Yutian; Konat, Gregory W; Wenger, Sharon L; Reed, Eddie; Wang, Weixin

    2007-04-01

    Tumor suppressor gene BRCA1 is frequently mutated in familial breast and ovarian cancer. BRCA1 plays pivotal roles in maintaining genomic stability by interacting with numerous proteins in cell cycle control and DNA repair. Irofulven (6-hydroxymethylacylfulvene, HMAF, MGI 114, NSC 683863) is one of a new class of anticancer agents that are analogs of mushroom-derived illudin toxins. Preclinical studies and clinical trials have demonstrated that irofulven is effective against several tumor cell types. The exact nature of irofulven-induced DNA damage is not completely understood. We demonstrated previously that irofulven activates ATM and its targets, NBS1, SMC1, CHK2, and p53. In this study, we hypothesize that irofulven induces DNA double-strand breaks and that BRCA1 may affect chemosensitivity by controlling cell cycle checkpoints, DNA repair, and genomic stability in response to irofulven treatment. We observed that irofulven induces the formation of chromosome breaks and radials and the activation and foci formation of gamma-H2AX, BRCA1, and RAD51. We also provided evidence that irofulven induces the generation of DNA double-strand breaks. By using BRCA1-deficient or -proficient cells, we demonstrated that in response to irofulven, BRCA1 contributes to the control of S and G(2)/M cell cycle arrest and is critical for repairing DNA double-strand breaks and for RAD51-dependent homologous recombination. Furthermore, we found that BRCA1 deficiency results in increased chromosome damage and chemosensitivity after irofulven treatment.

  10. Identification of domains of BRCA1 critical for the ubiquitin-dependent inhibition of centrosome function.

    Science.gov (United States)

    Sankaran, Satish; Starita, Lea M; Simons, Amanda M; Parvin, Jeffrey D

    2006-04-15

    The breast and ovarian cancer specific tumor suppressor BRCA1, bound to BARD1, has multiple functions aimed at maintaining genomic stability in the cell. We have shown earlier that the BRCA1/BARD1 E3 ubiquitin ligase activity regulates centrosome-dependent microtubule nucleation. In this study, we tested which domains of BRCA1 and BARD1 were required to control the centrosome function. In the present study, (a) we confirmed that the ubiquitination activity of BRCA1 regulates centrosome number and function in Hs578T breast cancer cells; (b) we observed that both the amino and carboxyl termini of BRCA1 are required for regulation of centrosome function in vitro; (c) an internal domain (770-1,290) is dispensable for centrosome regulation; (d) BARD1 is required for regulation of centrosome function and protein sequences within the terminal 485 amino acids are necessary for activity; and (e) BARD1 is localized at the centrosome throughout the cell cycle. We conclude that the BRCA1-dependent E3 ubiquitin ligase functions to restrain centrosomes in mammary cells, and loss of BRCA1 in the precancerous breast cell leads to centrosomal hypertrophy, a phenotype commonly observed in incipient breast cancer.

  11. Mechanisms of increased risk of tumorigenesis in Atm and Brca1 double heterozygosity

    Directory of Open Access Journals (Sweden)

    Wang Jufang

    2011-08-01

    Full Text Available Abstract Background Both epidemiological and experimental studies suggest that heterozygosity for a single gene is linked with tumorigenesis and heterozygosity for two genes increases the risk of tumor incidence. Our previous work has demonstrated that Atm/Brca1 double heterozygosity leads to higher cell transformation rate than single heterozygosity. However, the underlying mechanisms have not been fully understood yet. In the present study, a series of pathways were investigated to clarify the possible mechanisms of increased risk of tumorigenesis in Atm and Brca1 heterozygosity. Methods Wild type cells, Atm or Brca1 single heterozygous cells, and Atm/Brca1 double heterozygous cells were used to investigate DNA damage and repair, cell cycle, micronuclei, and cell transformation after photon irradiation. Results Remarkable high transformation frequency was confirmed in Atm/Brca1 double heterozygous cells compared to wild type cells. It was observed that delayed DNA damage recognition, disturbed cell cycle checkpoint, incomplete DNA repair, and increased genomic instability were involved in the biological networks. Haploinsufficiency of either ATM or BRCA1 negatively impacts these pathways. Conclusions The quantity of critical proteins such as ATM and BRCA1 plays an important role in determination of the fate of cells exposed to ionizing radiation and double heterozygosity increases the risk of tumorigenesis. These findings also benefit understanding of the individual susceptibility to tumor initiation.

  12. [Expression and clinical significance of BRCA1 in human esophageal squamous cell carcinoma].

    Science.gov (United States)

    Yang, Yi-xuan; Xue, Li-yan; Dong, Li-jia; Fu, Ming; Zhan, Qi-min; Tong, Tong

    2012-12-01

    To investigate the expression of BRCA1 in esophageal squamous cell carcinoma (ESCC) tissues and evaluate its correlation with clinicopathological features as well as the prognosis of ESCC patients. The expression of BRCA1 was detected by immunohistochemistry (IHC) in 201 specimens of T3 stage ESCC tissues and corresponding adjacent normal tissues using tissue microarray. The correlation between BRCA1 expression and clinicopathological features of ESCC was determined by chi-square analysis. The cumulative survival rate was analyzed by Kaplan-Meier method. The positive rate of BRCA1 expression in ESCC tissues was significantly higher than that in adjacent normal tissues [88.6% (178/201) vs. 36.8% (74/201), P 0.05). The results of Kaplan-Meier analysis indicated that ESCC patients with a higher positive rate of BRCA1 expression have a poorer prognosis (P < 0.05). The expression of BRCA1 is related to the occurrence and development of esophageal carcinoma. BRCA1 protein may serve as a new potential biomarker in estimating the biological behavior of ESCC.

  13. Methylation profiles of the BRCA1 promoter in hereditary and sporadic breast cancer among Han Chinese.

    Science.gov (United States)

    Pang, Da; Zhao, Yashuang; Xue, Weinan; Shan, Ming; Chen, Yanbo; Zhang, Youxue; Zhang, Guoqiang; Liu, Feng; Li, Dalin; Yang, Yanmei

    2012-09-01

    The development of breast cancer is a multistep process associated with complex changes in host gene expression patterns including inactivation of tumor suppressor genes and activation of oncogenes. Critically, hereditary predisposition plays a significant role in cancer susceptibility. However, mutation of the BRCA1 gene is found only in the minority of hereditary breast cancer, which indicates that there might be alternative, novel mechanisms contributing to inactivation of the BRCA1 gene. Studies have shown that aberrant methylation of genomic DNA plays an important role in carcinogenesis. The aim of this study was to investigate whether DNA methylation may be an alternative mechanism for the inactivation of BRCA1 as an epigenetic modification of the genome and whether hereditary breast cancer has a different BRCA1 methylation phenotype pattern than sporadic breast cancer. The pattern of CpG island methylation within the promoter region of BRCA1 was assessed by bisulfite sequencing DNA from peripheral blood cells of 72 patients with hereditary predisposition but without BRCA1 mutations and 30 sporadic breast cancer controls. The overall methylation level in patients with hereditary predisposition was significantly lower than that in the sporadic control group. However, patients with hereditary predisposition showed a significantly higher methylation susceptibility for the sites -518 when compared to controls. These results suggest that there might be different BRCA1 promoter methylation levels and patterns in sporadic and hereditary breast cancer in peripheral blood DNA. These findings may facilitate the early diagnosis of hereditary breast cancer.

  14. Male breast cancer in BRCA1 and BRCA2 mutation carriers: pathology data from the Consortium of Investigators of Modifiers of BRCA1/2.

    Science.gov (United States)

    Silvestri, Valentina; Barrowdale, Daniel; Mulligan, Anna Marie; Neuhausen, Susan L; Fox, Stephen; Karlan, Beth Y; Mitchell, Gillian; James, Paul; Thull, Darcy L; Zorn, Kristin K; Carter, Natalie J; Nathanson, Katherine L; Domchek, Susan M; Rebbeck, Timothy R; Ramus, Susan J; Nussbaum, Robert L; Olopade, Olufunmilayo I; Rantala, Johanna; Yoon, Sook-Yee; Caligo, Maria A; Spugnesi, Laura; Bojesen, Anders; Pedersen, Inge Sokilde; Thomassen, Mads; Jensen, Uffe Birk; Toland, Amanda Ewart; Senter, Leigha; Andrulis, Irene L; Glendon, Gord; Hulick, Peter J; Imyanitov, Evgeny N; Greene, Mark H; Mai, Phuong L; Singer, Christian F; Rappaport-Fuerhauser, Christine; Kramer, Gero; Vijai, Joseph; Offit, Kenneth; Robson, Mark; Lincoln, Anne; Jacobs, Lauren; Machackova, Eva; Foretova, Lenka; Navratilova, Marie; Vasickova, Petra; Couch, Fergus J; Hallberg, Emily; Ruddy, Kathryn J; Sharma, Priyanka; Kim, Sung-Won; Teixeira, Manuel R; Pinto, Pedro; Montagna, Marco; Matricardi, Laura; Arason, Adalgeir; Johannsson, Oskar Th; Barkardottir, Rosa B; Jakubowska, Anna; Lubinski, Jan; Izquierdo, Angel; Pujana, Miguel Angel; Balmaña, Judith; Diez, Orland; Ivady, Gabriella; Papp, Janos; Olah, Edith; Kwong, Ava; Nevanlinna, Heli; Aittomäki, Kristiina; Perez Segura, Pedro; Caldes, Trinidad; Van Maerken, Tom; Poppe, Bruce; Claes, Kathleen B M; Isaacs, Claudine; Elan, Camille; Lasset, Christine; Stoppa-Lyonnet, Dominique; Barjhoux, Laure; Belotti, Muriel; Meindl, Alfons; Gehrig, Andrea; Sutter, Christian; Engel, Christoph; Niederacher, Dieter; Steinemann, Doris; Hahnen, Eric; Kast, Karin; Arnold, Norbert; Varon-Mateeva, Raymonda; Wand, Dorothea; Godwin, Andrew K; Evans, D Gareth; Frost, Debra; Perkins, Jo; Adlard, Julian; Izatt, Louise; Platte, Radka; Eeles, Ros; Ellis, Steve; Hamann, Ute; Garber, Judy; Fostira, Florentia; Fountzilas, George; Pasini, Barbara; Giannini, Giuseppe; Rizzolo, Piera; Russo, Antonio; Cortesi, Laura; Papi, Laura; Varesco, Liliana; Palli, Domenico; Zanna, Ines; Savarese, Antonella; Radice, Paolo; Manoukian, Siranoush; Peissel, Bernard; Barile, Monica; Bonanni, Bernardo; Viel, Alessandra; Pensotti, Valeria; Tommasi, Stefania; Peterlongo, Paolo; Weitzel, Jeffrey N; Osorio, Ana; Benitez, Javier; McGuffog, Lesley; Healey, Sue; Gerdes, Anne-Marie; Ejlertsen, Bent; Hansen, Thomas V O; Steele, Linda; Ding, Yuan Chun; Tung, Nadine; Janavicius, Ramunas; Goldgar, David E; Buys, Saundra S; Daly, Mary B; Bane, Anita; Terry, Mary Beth; John, Esther M; Southey, Melissa; Easton, Douglas F; Chenevix-Trench, Georgia; Antoniou, Antonis C; Ottini, Laura

    2016-02-09

    BRCA1 and, more commonly, BRCA2 mutations are associated with increased risk of male breast cancer (MBC). However, only a paucity of data exists on the pathology of breast cancers (BCs) in men with BRCA1/2 mutations. Using the largest available dataset, we determined whether MBCs arising in BRCA1/2 mutation carriers display specific pathologic features and whether these features differ from those of BRCA1/2 female BCs (FBCs). We characterised the pathologic features of 419 BRCA1/2 MBCs and, using logistic regression analysis, contrasted those with data from 9675 BRCA1/2 FBCs and with population-based data from 6351 MBCs in the Surveillance, Epidemiology, and End Results (SEER) database. Among BRCA2 MBCs, grade significantly decreased with increasing age at diagnosis (P = 0.005). Compared with BRCA2 FBCs, BRCA2 MBCs were of significantly higher stage (P for trend = 2 × 10(-5)) and higher grade (P for trend = 0.005) and were more likely to be oestrogen receptor-positive [odds ratio (OR) 10.59; 95 % confidence interval (CI) 5.15-21.80] and progesterone receptor-positive (OR 5.04; 95 % CI 3.17-8.04). With the exception of grade, similar patterns of associations emerged when we compared BRCA1 MBCs and FBCs. BRCA2 MBCs also presented with higher grade than MBCs from the SEER database (P for trend = 4 × 10(-12)). On the basis of the largest series analysed to date, our results show that BRCA1/2 MBCs display distinct pathologic characteristics compared with BRCA1/2 FBCs, and we identified a specific BRCA2-associated MBC phenotype characterised by a variable suggesting greater biological aggressiveness (i.e., high histologic grade). These findings could lead to the development of gender-specific risk prediction models and guide clinical strategies appropriate for MBC management.

  15. Prevalence of BRCA1 Mutations in Familial and Sporadic Greek Ovarian Cancer Cases

    Science.gov (United States)

    Stavropoulou, Alexandra V.; Fostira, Florentia; Pertesi, Maroulio; Tsitlaidou, Marianthi; Voutsinas, Gerassimos E.; Triantafyllidou, Olga; Bamias, Aristotelis; Dimopoulos, Meletios A.; Timotheadou, Eleni; Pectasides, Dimitrios; Christodoulou, Christos; Klouvas, George; Papadimitriou, Christos; Makatsoris, Thomas; Pentheroudakis, George; Aravantinos, Gerasimos; Karydakis, Vassilis; Yannoukakos, Drakoulis; Fountzilas, George; Konstantopoulou, Irene

    2013-01-01

    Germline mutations in the BRCA1 and BRCA2 genes contribute to approximately 18% of hereditary ovarian cancers conferring an estimated lifetime risk from 15% to 50%. A variable incidence of mutations has been reported for these genes in ovarian cancer cases from different populations. In Greece, six mutations in BRCA1 account for 63% of all mutations detected in both BRCA1 and BRCA2 genes. This study aimed to determine the prevalence of BRCA1 mutations in a Greek cohort of 106 familial ovarian cancer patients that had strong family history or metachronous breast cancer and 592 sporadic ovarian cancer cases. All 698 patients were screened for the six recurrent Greek mutations (including founder mutations c.5266dupC, p.G1738R and the three large deletions of exon 20, exons 23–24 and exon 24). In familial cases, the BRCA1 gene was consequently screened for exons 5, 11, 12, 20, 21, 22, 23, 24. A deleterious BRCA1 mutation was found in 43/106 (40.6%) of familial cancer cases and in 27/592 (4.6%) of sporadic cases. The variant of unknown clinical significance p.V1833M was identified in 9/698 patients (1.3%). The majority of BRCA1 carriers (71.2%) presented a high-grade serous phenotype. Identifying a mutation in the BRCA1 gene among breast and/or ovarian cancer families is important, as it enables carriers to take preventive measures. All ovarian cancer patients with a serous phenotype should be considered for genetic testing. Further studies are warranted to determine the prevalence of mutations in the rest of the BRCA1 gene, in the BRCA2 gene, and other novel predisposing genes for breast and ovarian cancer. PMID:23536787

  16. Prevalence of BRCA1 mutations in familial and sporadic greek ovarian cancer cases.

    Directory of Open Access Journals (Sweden)

    Alexandra V Stavropoulou

    Full Text Available Germline mutations in the BRCA1 and BRCA2 genes contribute to approximately 18% of hereditary ovarian cancers conferring an estimated lifetime risk from 15% to 50%. A variable incidence of mutations has been reported for these genes in ovarian cancer cases from different populations. In Greece, six mutations in BRCA1 account for 63% of all mutations detected in both BRCA1 and BRCA2 genes. This study aimed to determine the prevalence of BRCA1 mutations in a Greek cohort of 106 familial ovarian cancer patients that had strong family history or metachronous breast cancer and 592 sporadic ovarian cancer cases. All 698 patients were screened for the six recurrent Greek mutations (including founder mutations c.5266dupC, p.G1738R and the three large deletions of exon 20, exons 23-24 and exon 24. In familial cases, the BRCA1 gene was consequently screened for exons 5, 11, 12, 20, 21, 22, 23, 24. A deleterious BRCA1 mutation was found in 43/106 (40.6% of familial cancer cases and in 27/592 (4.6% of sporadic cases. The variant of unknown clinical significance p.V1833M was identified in 9/698 patients (1.3%. The majority of BRCA1 carriers (71.2% presented a high-grade serous phenotype. Identifying a mutation in the BRCA1 gene among breast and/or ovarian cancer families is important, as it enables carriers to take preventive measures. All ovarian cancer patients with a serous phenotype should be considered for genetic testing. Further studies are warranted to determine the prevalence of mutations in the rest of the BRCA1 gene, in the BRCA2 gene, and other novel predisposing genes for breast and ovarian cancer.

  17. BRCA1 Circos: a visualisation resource for functional analysis of missense variants.

    Science.gov (United States)

    Jhuraney, Ankita; Velkova, Aneliya; Johnson, Randall C; Kessing, Bailey; Carvalho, Renato S; Whiley, Phillip; Spurdle, Amanda B; Vreeswijk, Maaike P G; Caputo, Sandrine M; Millot, Gael A; Vega, Ana; Coquelle, Nicolas; Galli, Alvaro; Eccles, Diana; Blok, Marinus J; Pal, Tuya; van der Luijt, Rob B; Santamariña Pena, Marta; Neuhausen, Susan L; Donenberg, Talia; Machackova, Eva; Thomas, Simon; Vallée, Maxime; Couch, Fergus J; Tavtigian, Sean V; Glover, J N Mark; Carvalho, Marcelo A; Brody, Lawrence C; Sharan, Shyam K; Monteiro, Alvaro N

    2015-04-01

    Inactivating germline mutations in the tumour suppressor gene BRCA1 are associated with a significantly increased risk of developing breast and ovarian cancer. A large number (>1500) of unique BRCA1 variants have been identified in the population and can be classified as pathogenic, non-pathogenic or as variants of unknown significance (VUS). Many VUS are rare missense variants leading to single amino acid changes. Their impact on protein function cannot be directly inferred from sequence information, precluding assessment of their pathogenicity. Thus, functional assays are critical to assess the impact of these VUS on protein activity. BRCA1 is a multifunctional protein and different assays have been used to assess the impact of variants on different biochemical activities and biological processes. To facilitate VUS analysis, we have developed a visualisation resource that compiles and displays functional data on all documented BRCA1 missense variants. BRCA1 Circos is a web-based visualisation tool based on the freely available Circos software package. The BRCA1 Circos web tool (http://research.nhgri.nih.gov/bic/circos/) aggregates data from all published BRCA1 missense variants for functional studies, harmonises their results and presents various functionalities to search and interpret individual-level functional information for each BRCA1 missense variant. This research visualisation tool will serve as a quick one-stop publically available reference for all the BRCA1 missense variants that have been functionally assessed. It will facilitate meta-analysis of functional data and improve assessment of pathogenicity of VUS. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

  18. Pathology of Breast and Ovarian Cancers among BRCA1 and BRCA2 Mutation Carriers: Results from the Consortium of Investigators of Modifiers of BRCA1/2 (CIMBA)

    DEFF Research Database (Denmark)

    Mavaddat, Nasim; Barrowdale, Daniel; Andrulis, Irene L

    2012-01-01

    BACKGROUND: Previously, small studies have found that BRCA1 and BRCA2 breast tumors differ in their pathology. Analysis of larger datasets of mutation carriers should allow further tumor characterization. METHODS: We used data from 4,325 BRCA1 and 2,568 BRCA2 mutation carriers to analyze...... the pathology of invasive breast, ovarian, and contralateral breast cancers. RESULTS: There was strong evidence that the proportion of estrogen receptor (ER)-negative breast tumors decreased with age at diagnosis among BRCA1 (P-trend = 1.2 × 10(-5)), but increased with age at diagnosis among BRCA2, carriers (P......-trend = 6.8 × 10(-6)). The proportion of triple-negative tumors decreased with age at diagnosis in BRCA1 carriers but increased with age at diagnosis of BRCA2 carriers. In both BRCA1 and BRCA2 carriers, ER-negative tumors were of higher histologic grade than ER-positive tumors (grade 3 vs. grade 1; P = 1...

  19. BRCA1 Accelerates CtIP-Mediated DNA-End Resection

    Directory of Open Access Journals (Sweden)

    Andrés Cruz-García

    2014-10-01

    Full Text Available DNA-end resection is a highly regulated and critical step in the response and repair of DNA double-strand breaks. In higher eukaryotes, CtIP regulates resection by integrating cellular signals via its posttranslational modifications and protein-protein interactions, including cell-cycle-controlled interaction with BRCA1. The role of BRCA1 in DNA-end resection is not clear. Here, we develop an assay to study DNA resection in higher eukaryotes at high resolution. We demonstrate that the BRCA1-CtIP interaction, albeit not essential for resection, modulates the speed at which this process takes place.

  20. BRCA1 Expression is an Important Biomarker for Chemosensitivity: Suppression of BRCA1 Increases the Apoptosis via Up-regulation of p53 and p21 During Cisplatin Treatment in Ovarian Cancer Cells

    Directory of Open Access Journals (Sweden)

    Ikuo Konishi

    2006-01-01

    Full Text Available BRCA1 is a tumor suppressor which plays a crucial role in the repair of DNA double-strand breaks, and its abnormality is responsible for hereditary ovarian cancer syndrome. It has recently been reported that reduced expression of BRCA1 is also common in sporadic ovarian carcinoma via its promoter hypermethylation, and that ovarian carcinoma patients negative for BRCA1 expression showed favorable prognosis. To address if BRCA1 expression plays a role in the chemotherapeutic response, we analyzed the effect of BRCA1 suppression on the sensitivity to cisplatin and paclitaxel in ovarian cancer cells. Specific siRNA for BRCA1 gene was transfected into 3 ovarian cancer cell lines with various p53 status. Reduced expression of BRCA1 by transfection of BRCA1-siRNA resulted in a 5.3-fold increase in sensitivity to cisplatin in p53-wild A2780 cells, but not in p53-mutated A2780/CDDP and p53-deleted SKOV3 cells. Regarding the sensitivity to paclitaxel, BRCA1 suppression caused no significant changes in all the 3 cell lines. For ionizing radiation sensitivity, BRCA1 suppression also showed a significant higher sensitivity in A2780 cells. Growth curve and cell cycle analyses showed no signifi cant differences between BRCA1-siRNA-transfected A2780 cells and control cells. However, cisplatin treatment under suppression of BRCA1 showed a significantly increased apoptosis along with up-regulation of p53 and p21 in A2780 cells. Accordingly, reduced expression of BRCA1 enhances the cisplatin sensitivity and apoptosis via up-regulation of p53 and p21, but does not affect the paclitaxel sensitivity. Expression of BRCA1 might be an important biomarker for cisplatin resistance in ovarian carcinoma.

  1. Large BRCA1 and BRCA2 genomic rearrangements in Danish high risk breast-ovarian cancer families

    DEFF Research Database (Denmark)

    Hansen, Thomas v O; Jønson, Lars; Albrechtsen, Anders

    2009-01-01

    BRCA1 and BRCA2 germ-line mutations predispose to breast and ovarian cancer. Large genomic rearrangements of BRCA1 account for 0-36% of all disease causing mutations in various populations, while large genomic rearrangements in BRCA2 are more rare. We examined 642 East Danish breast and/or ovarian...... cancer patients in whom a deleterious mutation in BRCA1 and BRCA2 was not detected by sequencing using the multiplex ligation-dependent probe amplification (MLPA) assay. We identified 15 patients with 7 different genomic rearrangements, including a BRCA1 exon 5-7 deletion with a novel breakpoint, a BRCA1...... exon 13 duplication, a BRCA1 exon 17-19 deletion, a BRCA1 exon 3-16 deletion, and a BRCA2 exon 20 deletion with a novel breakpoint as well as two novel BRCA1 exon 17-18 and BRCA1 exon 19 deletions. The large rearrangements in BRCA1 and BRCA2 accounted for 9.2% (15/163) of all BRCA1 and BRCA2 mutations...

  2. TP53 status for prediction of sensitivity to taxane versus non-taxane neoadjuvant chemotherapy in breast cancer (EORTC 10994/BIG 1-00): a randomised phase 3 trial.

    Science.gov (United States)

    Bonnefoi, Hervé; Piccart, Martine; Bogaerts, Jan; Mauriac, Louis; Fumoleau, Pierre; Brain, Etienne; Petit, Thierry; Rouanet, Philippe; Jassem, Jacek; Blot, Emmanuel; Zaman, Khalil; Cufer, Tanja; Lortholary, Alain; Lidbrink, Elisabet; André, Sylvie; Litière, Saskia; Lago, Lissandra Dal; Becette, Véronique; Cameron, David A; Bergh, Jonas; Iggo, Richard

    2011-06-01

    TP53 has a crucial role in the DNA damage response. We therefore tested the hypothesis that taxanes confer a greater advantage than do anthracyclines on breast cancers with mutated TP53 than in those with wild-type TP53. In an open-label, phase 3 study, women (age <71 years) with locally advanced, inflammatory, or large operable breast cancers were randomly assigned in a 1:1 ratio to either a standard anthracycline regimen (six cycles of intravenous fluorouracil 500 mg/m², epirubicin 100 mg/m², and cyclophosphamide 500 mg/m² every 21 days [FEC100], or fluorouracil 600 mg/m², epirubicin 75 mg/m², cyclophosphamide 900 mg/m² [tailored FEC] starting on day 1 and then every 21 days) or a taxane-based regimen (three cycles of docetaxel 100 mg/m², intravenously infused over 1 h on day 1 every 21 days, followed by three cycles of intravenous epirubicin 90 mg/m² and docetaxel 75 mg/m² on day 1 every 21 days [T-ET]) at 42 centres in Europe. Randomisation was by use of a minimisation method that stratified patients by institution and initial tumour stage. The primary endpoint was progression-free survival (PFS) according to TP53 status. Analysis was by intention to treat. This is the final analysis of this trial. The study is registered with ClinicalTrials.gov, number NCT00017095. 928 patients were enrolled in the FEC group and 928 in the T-ET group. TP53 status was not assessable for 183 (20%) patients in the FEC group and 204 (22%) patients in the T-ET group mainly because of low tumour-cell content in the biopsy. 361 primary endpoint events were recorded in the FEC group and 314 in the T-ET group. In patients with TP53-mutated tumours, 5-year PFS was 59·5% (95% CI 53·4-65·1) in the T-ET group (n=326) and 55·3% (49·2-60·9) in the FEC group (n=318; hazard ratio 0·84, 98% CI 0·63-1·14; p=0·17). In patients with TP53 wild-type tumours, 5-year PFS was 66·8% (95% CI 61·4-71·6) in the T-ET group (n=398) and 64·7% (59·6-69·4) in the FEC group (n=427; 0·89

  3. High SINE RNA Expression Correlates with Post-Transcriptional Downregulation of BRCA1

    Directory of Open Access Journals (Sweden)

    Giovanni Bosco

    2013-04-01

    Full Text Available Short Interspersed Nuclear Elements (SINEs are non-autonomous retrotransposons that comprise a large fraction of the human genome. SINEs are demethylated in human disease, but whether SINEs become transcriptionally induced and how the resulting transcripts may affect the expression of protein coding genes is unknown. Here, we show that downregulation of the mRNA of the tumor suppressor gene BRCA1 is associated with increased transcription of SINEs and production of sense and antisense SINE small RNAs. We find that BRCA1 mRNA is post-transcriptionally down-regulated in a Dicer and Drosha dependent manner and that expression of a SINE inverted repeat with sequence identity to a BRCA1 intron is sufficient for downregulation of BRCA1 mRNA. These observations suggest that transcriptional activation of SINEs could contribute to a novel mechanism of RNA mediated post-transcriptional silencing of human genes.

  4. A high frequent BRCA1 founder mutation identified in the Greenlandic population

    DEFF Research Database (Denmark)

    Harboe, Theresa Larriba; Eiberg, Hans; Kern, Peder

    2009-01-01

    Approximately 10% of all breast and ovarian cancers are dominantly inherited and mutations are mainly found in the BRCA 1 and 2 genes. The penetrance of BRCA1 mutations is reported to be between 68 and 92% and confers a 36-92% life time risk of breast cancer. Most mutations in BRCA1 are uniquely...... the clinical relevance of the mutation, we have examined ten breast cancer patients and nine ovarian cancer patients from Greenland for the presence of the p.Cys39Gly mutation. We found three ovarian cancer patients (33%) and one breast cancer patient (10%) carrying the mutation. The high number of women...... carrying a BRCA1 mutation known to trigger the development of potentially lethal diseases leads us to recommend an offer of genetic counselling and test for the mutation to all females of Inuit origin, thereby hopefully preventing a number of breast and ovarian cancer deaths....

  5. Risk modeling and screening for BRCA1 mutations among Filipino breast cancer patients

    CERN Document Server

    Nato, A Q J

    2003-01-01

    Breast cancer susceptibility gene, type 1(BRCA1) has been thought to be responsible for approx 45% of families with multiple breast carcinomas and for approx 80% of breast and ovarian cancer families. In this study, we investigated 34 familial Filipino breast cancer (BC) patients to: (a) estimate breast cancer risks and BRCA1/2 mutation carrier probabilities using risk assessment and prior probability models, respectively; (b) screen for putative polymorphisms at selected smaller exons of BRCA1 by single-strand conformation polymorphism (SSCP) analysis; (c) screen for truncated mutations at BRCA1 exon 11 by radioactive protein truncation test (PTT); and (d) estimate posterior probabilities upon incorporation of screening results. SSCP analysis revealed 8 unique putative polymorphisms. Low prevalence of unique putative polymorphisms at exon 2, 5, 17, and 22 may indicate probable mutations. Contrastingly, high prevalence of unique putative polymorphisms at exons 13, 15, and 16 may suggest true polymorphisms whi...

  6. A guide for functional analysis of BRCA1 variants of uncertain significance

    DEFF Research Database (Denmark)

    Millot, Gaël A; Carvalho, Marcelo A; Caputo, Sandrine M

    2012-01-01

    Germline mutations in the tumor suppressor gene BRCA1 confer an estimated lifetime risk of 56-80% for breast cancer and 15-60% for ovarian cancer. Since the mid 1990s when BRCA1 was identified, genetic testing has revealed over 1,500 unique germline variants. However, for a significant number...... of these variants, the effect on protein function is unknown making it difficult to infer the consequences on risks of breast and ovarian cancers. Thus, many individuals undergoing genetic testing for BRCA1 mutations receive test results reporting a variant of uncertain clinical significance (VUS), leading...... to issues in risk assessment, counseling, and preventive care. Here, we describe functional assays for BRCA1 to directly or indirectly assess the impact of a variant on protein conformation or function and how these results can be used to complement genetic data to classify a VUS as to its clinical...

  7. The Prognostic Value of BRCA1 and PARP Expression in Epithelial Ovarian Carcinoma

    DEFF Research Database (Denmark)

    Hjortkjær, Mette; Waldstrøm, Marianne; Jakobsen, Anders

    2017-01-01

    BRCA1/2 mutation status in epithelial ovarian cancer (EOC) presently relies on genetic testing which is resource consuming. Immunohistochemistry is cheap, fairly reproducible, and may identify gene product alterations due to both germline and somatic mutations and other defects along the BRCA gene...... pathway (BRCAness phenomenon), which is important when treatment with poly (adenosine-diphosphate-ribose) polymerase (PARP) inhibitors is considered. The aim of this study was to investigate immunohistochemical detection of BRCA1 and PARP expression in EOC and their possible prognostic relevance. Tumor...... tissue from 170 patients with EOC was stained immunohistochemically with BRCA1 and PARP antibodies. Semiquantitative analyses were performed to determine loss of, equivocal, and retained BRCA1 and high versus low PARP protein expression. These parameters were analyzed for relation with patient...

  8. Screening of BRCA1 sequence variants within exon 11 by heteroduplex analysis

    Directory of Open Access Journals (Sweden)

    Lucian Negura

    2013-03-01

    Full Text Available Germ-line mutations of either BRCA1 or BRCA2 represents the major hereditary risk to breast and ovariancancer. Screening for mutations in these genes is now standard practice in molecular diagnosis, opening the way tooncogenetic counselling and follow-up. Because mutations in both BRCA1 and BRCA2 are distributed throughout theloci, accepted clinical protocols involve screening their entire coding regions. Systematic Sanger sequencing is time andmoney consuming. Therefore, a lot of pre-screening techniques evolved over time in order to identify anomalousamplicons prior to sequencing. Because BRCA mutations are always heterozygous, heteroduplex analysis proved to be asuitable pre-screening step. We previously implemented mismatch specific endonuclease heteroduplex analysis forBRCA1 exon7. Here we show the utility of the same method for mutations and SNPs found in BRCA1 exon 11

  9. A Genetic Screen for Genes Involved in BRCA 1 Tumor Suppressor Function

    National Research Council Canada - National Science Library

    Verma, Inder; Zhu, Quan

    2007-01-01

    Based on our initial screening, we have identified a number of candidates that are involved in DNA damage repair pathway mediated by BRCA1, which is an important aspect of tumor suppression of the molecular...

  10. Women with BRCA1 and BRCA2 mutations survive ovarian cancer at higher rates

    Science.gov (United States)

    Results from a National Cancer Institute (NCI) sponsored multicenter study published in the Journal of the American Medical Association on January 25, 2012, provides strong evidence that BRCA1 and BRCA2 gene mutation carriers with ovarian cancer were more

  11. Comprehensive spectrum of BRCA1 and BRCA2 deleterious mutations in breast cancer in Asian countries

    Science.gov (United States)

    Kwong, Ava; Shin, Vivian Y; Ho, John C W; Kang, Eunyoung; Nakamura, Seigo; Teo, Soo-Hwang; Lee, Ann S G; Sng, Jen-Hwei; Ginsburg, Ophira M; Kurian, Allison W; Weitzel, Jeffrey N; Siu, Man-Ting; Law, Fian B F; Chan, Tsun-Leung; Narod, Steven A; Ford, James M; Ma, Edmond S K; Kim, Sung-Won

    2015-01-01

    Approximately 5%–10% of breast cancers are due to genetic predisposition caused by germline mutations; the most commonly tested genes are BRCA1 and BRCA2 mutations. Some mutations are unique to one family and others are recurrent; the spectrum of BRCA1/BRCA2 mutations varies depending on the geographical origins, populations or ethnic groups. In this review, we compiled data from 11 participating Asian countries (Bangladesh, Mainland China, Hong Kong SAR, Indonesia, Japan, Korea, Malaysia, Philippines, Singapore, Thailand and Vietnam), and from ethnic Asians residing in Canada and the USA. We have additionally conducted a literature review to include other Asian countries mainly in Central and Western Asia. We present the current pathogenic mutation spectrum of BRCA1/BRCA2 genes in patients with breast cancer in various Asian populations. Understanding BRCA1/BRCA2 mutations in Asians will help provide better risk assessment and clinical management of breast cancer. PMID:26187060

  12. BRCA1 and BRCA2 mutations in breast cancer patients from Venezuela

    National Research Council Canada - National Science Library

    Lara, Karlena; Consigliere, Nigmet; Pérez, Jorge; Porco, Antonietta

    2012-01-01

    A sample of 58 familial breast cancer patients from Venezuela were screened for germline mutations in the coding sequences and exon-intron boundaries of BRCA1 (MIM no. 113705) and BRCA2 (MIM no. 600185...

  13. miR-342 regulates BRCA1 expression through modulation of ID4 in breast cancer.

    Directory of Open Access Journals (Sweden)

    Elisabetta Crippa

    Full Text Available A miRNAs profiling on a group of familial and sporadic breast cancers showed that miRNA-342 was significantly associated with estrogen receptor (ER levels. To investigate at functional level the role of miR-342 in the pathogenesis of breast cancer, we focused our attention on its "in silico" predicted putative target gene ID4, a transcription factor of the helix-loop-helix protein family whose expression is inversely correlated with that of ER. ID4 is expressed in breast cancer and can negatively regulate BRCA1 expression. Our results showed an inverse correlation between ID4 and miR-342 as well as between ID4 and BRCA1 expression. We functionally validated the interaction between ID4 and miR-342 in a reporter Luciferase system. Based on these findings, we hypothesized that regulation of ID4 mediated by miR-342 could be involved in the pathogenesis of breast cancer by downregulating BRCA1 expression. We functionally demonstrated the interactions between miR-342, ID4 and BRCA1 in a model provided by ER-negative MDA-MB-231 breast cancer cell line that presented high levels of ID4. Overexpression of miR-342 in these cells reduced ID4 and increased BRCA1 expression, supporting a possible role of this mechanism in breast cancer. In the ER-positive MCF7 and in the BRCA1-mutant HCC1937 cell lines miR-342 over-expression only reduced ID4. In the cohort of patients we studied, a correlation between miR-342 and BRCA1 expression was found in the ER-negative cases. As ER-negative cases were mainly BRCA1-mutant, we speculate that the mechanism we demonstrated could be involved in the decreased expression of BRCA1 frequently observed in non BRCA1-mutant breast cancers and could be implicated as a causal factor in part of the familial cases grouped in the heterogeneous class of non BRCA1 or BRCA2-mutant cases (BRCAx. To validate this hypothesis, the study should be extended to a larger cohort of ER-negative cases, including those belonging to the BRCAx class.

  14. Recurrent BRCA1 and BRCA2 mutations in breast cancer patients of African ancestry.

    Science.gov (United States)

    Zhang, Jing; Fackenthal, James D; Zheng, Yonglan; Huo, Dezheng; Hou, Ningqi; Niu, Qun; Zvosec, Cecilia; Ogundiran, Temidayo O; Hennis, Anselm J; Leske, Maria Cristina; Nemesure, Barbara; Wu, Suh-Yuh; Olopade, Olufunmilayo I

    2012-07-01

    Recurrent mutations constituted nearly three quarters of all BRCA1 mutations and almost half of all BRCA2 mutations identified in the first cohort of the Nigerian Breast Cancer Study. To further characterize breast/ovarian cancer risks associated with BRCA1/BRCA2 mutations in the African diaspora, we genotyped recurrent mutations among Nigerian, African American, and Barbadian breast cancer patients. A replication cohort of 356 Nigerian breast cancer patients was genotyped for 12 recurrent BRCA1/2 mutant alleles (Y101X, 1742insG, 4241delTG, M1775R, 4359insC, C64Y, 1623delTTAAA, Q1090X, and 943ins10 from BRCA1, and 1538delAAGA, 2630del11, and 9045delGAAA from BRCA2) by means of SNaPshot followed by direct sequencing or by direct sequencing alone. In addition, 260 African Americans and 118 Barbadians were genotyped for six of the recurrent BRCA1 mutations by SNaPshot assay. Of all the BRCA1/2 recurrent mutations we identified in the first cohort, six were identified in 11 patients in the replication study. These mutation carriers constitute 3.1 % [95 % Confidence Interval (CI) 1.6-5.5 %] of the replication cohort. By comparison, 6.9 % (95 % CI 4.7-9.7 %) of the discovery cohort carried BRCA1/2 recurrent mutations. For the subset of recurrent mutations we tested in breast cancer cases from Barbados or the United States, only two 943ins10 carriers were identified in African Americans. Nigerian breast cancer patients from Ibadan carry a broad and unique spectrum of BRCA1/2 mutations. Our data suggest that BRCA1/2 mutation testing limited to recurrent mutations is not sufficient to understand the BRCA1/2-associated breast cancer risk in African populations in the diaspora. As the cost of Sanger sequencing is considerably reduced, deploying innovative technologies such as high throughput DNA sequencing of BRCA1/2 and other cancer susceptibility genes will be essential for identifying high-risk individuals and families to reduce the burden of aggressive early onset breast

  15. Mechanism of Ovarian Epithelial Tumor Predisposition in Individuals Carrying Germline BRCA1 Mutations

    Science.gov (United States)

    2006-12-01

    cystadenomas , which are benign tumors made up of the same cell type as ovarian serous carcinomas. We confirmed that these tumors carried only the wild type... cystadenomas in strong support of our hypothesis. We proposed to elucidate the mechanism of tumor predisposition in this mouse model by identifying the...Maxson R, Dubeau L: Inactivation of Brca1 in mouse ovarian granulosa cells causes serous epithelial cystadenomas carrying functional Brca1alleles in

  16. BRCA1 genetic mutation and its link to ovarian cancer: implications for advanced practice nurses.

    Science.gov (United States)

    Brunsvold, Amy N; Wung, Shu-Fen; Merkle, Carrie J

    2005-12-01

    The purpose of this paper is to review (a) the linkage between the BRCA1 gene and ovarian cancer and (b) BRCA1 testing and its related issues. This review is aimed for nurse practitioners (NPs), who may be in positions to identify those at risk for BRCA1-associated ovarian cancer and to assist patients with related issues. Data sources include reviews and original research from scholarly journals and Internet sites. Ovarian cancer is a deadly disease. Identification of those at risk because of BRCA1 mutation is possible through genetic testing. Testing for BRCA1 gene mutations has many implications whether results are positive or negative. Those with positive results will be faced with decisions regarding the best management strategies. Negative results do not completely eliminate ovarian cancer risk. Current management options for carriers of the BRCA1 mutation include taking no action, increasing surveillance for ovarian cancer, and chemoprevention with oral contraceptives or prophylactic oophorectomy for those who have completed childbearing. It is essential that NPs have knowledge underlying the issues and concerns of patients and their families at risk for BRCA1-associated ovarian cancer. NPs are in a unique position to help identify BRCA1 mutation carriers and to assist them and their families with the complex issues involving genetic testing and management options. Understanding these issues will allow NPs to give appropriate care that may include making appropriate referrals to certified genetic counselors and having balanced discussions on treatment options. Such measurements may improve early diagnosis of ovarian cancer and increase survival from this disease.

  17. Microglandular adenosis of the breast in a BRCA1 mutation carrier: radiological features

    Energy Technology Data Exchange (ETDEWEB)

    Sabate, J.M.; Gomez, A.; Torrubia, S. [Department of Diagnostic Radiology, Hospital de Sant Pau, Universitat Autonoma de Barcelona (Spain); Matias-Guiu, X. [Department of Pathology, Hospital de Sant Pau, Universitat Autonoma de Barcelona (Spain); Alonso, C.; Pericay, C. [Department of Oncology, Hospital de Sant Pau, Universitat Autonoma de Barcelona, Sant Antoni M. Claret, 167, 08025 Barcelona (Spain); Diaz, O. [Department of Genetics, Hospital de Sant Pau, Universitat Autonoma de Barcelona (Spain)

    2002-06-01

    Microglandular adenosis is a very uncommon benign proliferative disorder of the breast that may mimic tubular carcinoma radiologically and pathologically. We describe the radiological features of this rare condition in a patient with BRCA 1 mutation. To our knowledge, this is the first case of microglandular adenosis reported in the radiology literature. The relationship between microglandular adenosis and malignancy and the association between BRCA 1 and proliferative benign disorders are also discussed. (orig.)

  18. The Role of BRCA1 in Suppressing Epithelial Mesenchymal Transition in Mammary Gland and Tumor Development

    Science.gov (United States)

    2016-11-01

    pathology and expression of CK5 and CK14 in these samples with mouse mammary tumors. We noticed that both the tumor cell morphology and expression pattern...AWARD NUMBER: W81XWH-13-1-0282 TITLE: The Role of BRCA1 in Suppressing Epithelial-Mesenchymal Transition in Mammary Gland and Tumor...2013 - 31-AUG-2016 4. TITLE AND SUBTITLE The Role of BRCA1 in Suppressing Epithelial-Mesenchymal Transition in Mammary Gland and Tumor Development 5a

  19. BRCA1 function in T lymphocytes: a cellular specificity of a different kind

    OpenAIRE

    Gardner, Kevin; Liu, Edison T

    2000-01-01

    Recent work by Mak et al demonstrates that mice carrying a T-cell-specific disruption of the brca1 gene display markedly impaired T-lymphocyte development and proliferation in the absence of any increased tendency for the formation of tumors. Interestingly, the extent of these defects was found to be highly dependent on cellular context. Contrasting the rather broad tissue expression pattern of brca1 against its exquisitely selective etiologic role in cancers of the breast and ovary, many of ...

  20. BRCA1 and BRCA2 Germline Mutations Screening in Algerian Breast/Ovarian Cancer Families

    Directory of Open Access Journals (Sweden)

    Farid Cherbal

    2010-01-01

    Full Text Available Background: Breast cancer is the leading cause of cancer death in women in Algeria. The contribution of BRCA1 and BRCA2 mutations to hereditary breast/ovarian cancer in Algerian population is largely unknown. Here, we describe analysis of BRCA1 and BRCA2 genes in 86 individuals from 70 families from an Algerian cohort with a personal and family history suggestive of genetic predisposition to breast cancer.

  1. Construction, Expression and Purification of Wild and Mutant Type of nm23-H1 in Prokaryotic Expression System

    Directory of Open Access Journals (Sweden)

    Xueqin YANG

    2009-01-01

    Full Text Available Background and objective Nm23-H1 is a metastasis-suppressor gene. However, its molecular mechanism of suppressing metastasis is unknown until now. The aim of this study is to construct prokaryotic expression vector of wild and mutant type of nm23-H1 (WT, P96S, H118F, and then express and purify the proteins. Methods wild and mutant type of nm23-H1 fragments were amplified by PCR. The prokaryotic expression vectors of pET28anm23-H1 were constructed by gene recombination technique and verified by restriction enzyme analysis and sequencing. The positive clones were transformed into E. coli BL21 (DE3 and soluble analysis of the expression was conducted in this system. The proteins were purified by nickel column chromatography and identified by Western blot. Results Thesequences and open read frames of all the pET28a-nm23-H1 plasmids were completely correct. After transforming, these plasmids can express the target proteins. The protein production was very high, and all the proteins were soluble expression. The molecular weight of wild and mutant type of nm23-H1 was 20 kDa detected by Western blot, which was as the same as the objective protein. Conclusion We have succeeded in constructing the prokaryotic expression vectors ofpET28a-nm23-H1 (WT, P96S, H118F and the proteins which expressed can be used in following studies.

  2. Effects of Radiation Therapy on Breast Epithelial Cells in BRCA1/2 Mutation Carriers.

    Science.gov (United States)

    Chiang, Huai-Chin; Elledge, Richard; Larson, Paula; Jatoi, Ismail; Li, Rong; Hu, Yanfen

    2015-01-01

    Women carrying BRCA1 and BRCA2 mutations have significantly elevated risk of developing breast and ovarian cancers. BRCA1-associated breast cancer likely originates from progenitors of the luminal epithelial lineage. Recent studies indicate that radiation therapy (RT) for BRCA1 cancer patients is associated with lower incidence of developing subsequent ipsilateral breast cancer. In the current study, we analyzed tumor-free breast tissue procured via prophylactic bilateral mastectomy from three BRCA1 and one BRCA2 mutation carriers, who had been previously treated with RT for unilateral breast cancers. Freshly isolated breast cells from the irradiated and nonirradiated breast tissue of the same individuals were subjected to flow cytometry, using established cell-surface markers. Two out of the three BRCA1 carriers and one BRCA2 carrier exhibited significantly diminished luminal cell population in the irradiated breast versus the nonirradiated side. There was also RT-associated reduction in the colony-forming ability of the breast epithelial cells. Our finding suggests that prior RT could result in the depletion of the luminal epithelial compartment and thus reduced incidence of BRCA1/2-associated breast cancer.

  3. BRCA1 haploinsufficiency leads to altered expression of genes involved in cellular proliferation and development.

    Directory of Open Access Journals (Sweden)

    Harriet E Feilotter

    Full Text Available The assessment of BRCA1 and BRCA2 coding sequences to identify pathogenic mutations associated with inherited breast/ovarian cancer syndrome has provided a method to identify high-risk individuals, allowing them to seek preventative treatments and strategies. However, the current test is expensive, and cannot differentiate between pathogenic variants and those that may be benign. Focusing only on one of the two BRCA partners, we have developed a biological assay for haploinsufficiency of BRCA1. Using a series of EBV-transformed cell lines, we explored gene expression patterns in cells that were BRCA1 wildtype compared to those that carried (heterozygous BRCA1 pathogenic mutations. We identified a subset of 43 genes whose combined expression pattern is a sensitive predictor of BRCA1 status. The gene set was disproportionately made up of genes involved in cellular differentiation, lending credence to the hypothesis that single copy loss of BRCA1 function may impact differentiation, rendering cells more susceptible to undergoing malignant processes.

  4. A Novel Pathogenic BRCA1 Splicing Variant Produces Partial Intron Retention in the Mature Messenger RNA

    Directory of Open Access Journals (Sweden)

    Maria Valeria Esposito

    2016-12-01

    Full Text Available About 10% of all breast cancers arise from hereditary mutations that increase the risk of breast and ovarian cancers; and about 25% of these are associated with the BRCA1 or BRCA2 genes. The identification of BRCA1/BRCA2 mutations can enable physicians to better tailor the clinical management of patients; and to initiate preventive measures in healthy carriers. The pathophysiological significance of newly identified variants poses challenges for genetic counseling. We characterized a new BRCA1 variant discovered in a breast cancer patient during BRCA1/2 screening by next-generation sequencing. Bioinformatic predictions; indicating that the variant is probably pathogenetic; were verified using retro-transcription of the patient’s RNA followed by PCR amplifications performed on the resulting cDNA. The variant causes the loss of a canonic donor splice site at position +2 in BRCA1 intron 21; and consequently the partial retention of 156 bp of intron 21 in the patient’s transcript; which demonstrates that this novel BRCA1 mutation plays a pathogenetic role in breast cancer. These findings enabled us to initiate appropriate counseling and to tailor the clinical management of this family. Lastly; these data reinforce the importance of studying the effects of sequence variants at the RNA level to verify their potential role in disease onset.

  5. BRCA1 and CtIP suppress long tract gene conversion between sister chromatids

    Science.gov (United States)

    Chandramouly, Gurushankar; Kwok, Amy; Huang, Bin; Willis, Nicholas A.; Xie, Anyong; Scully, Ralph

    2013-01-01

    BRCA1 controls early steps of the synthesis-dependent strand annealing (SDSA) pathway of homologous recombination, but has no known role following Rad51-mediated synapsis. Here we show that BRCA1 influences post-synaptic homologous recombination events, controlling the balance between short- (STGC) and long-tract gene conversion (LTGC) between sister chromatids. Brca1 mutant cells reveal a bias towards LTGC that is corrected by expression of wild type but not cancer-predisposing BRCA1 alleles. The LTGC bias is enhanced by depletion of CtIP but reversed by inhibition of 53BP1, implicating DNA end resection as a contributor to the STGC/LTGC balance. The impact of BRCA1/CtIP loss on the STGC/LTGC balance is abolished when the second (non-invading) end of the break is unable to support termination of STGC by homologous pairing (“annealing”). This suggests that BRCA1/CtIP-mediated processing of the second end of the break controls the annealing step that normally terminates SDSA, thereby suppressing the error-prone LTGC outcome. PMID:23994874

  6. BRCA1 and CtIP suppress long-tract gene conversion between sister chromatids.

    Science.gov (United States)

    Chandramouly, Gurushankar; Kwok, Amy; Huang, Bin; Willis, Nicholas A; Xie, Anyong; Scully, Ralph

    2013-01-01

    BRCA1 controls early steps of the synthesis-dependent strand annealing (SDSA) pathway of homologous recombination, but has no known role following Rad51-mediated synapsis. Here we show that BRCA1 influences post-synaptic homologous recombination events, controlling the balance between short- (STGC) and long-tract gene conversion (LTGC) between sister chromatids. Brca1 mutant cells reveal a bias towards LTGC that is corrected by expression of wild-type but not cancer-predisposing BRCA1 alleles. The LTGC bias is enhanced by depletion of CtIP but reversed by inhibition of 53BP1, implicating DNA end resection as a contributor to the STGC/LTGC balance. The impact of BRCA1/CtIP loss on the STGC/LTGC balance is abolished when the second (non-invading) end of the break is unable to support termination of STGC by homologous pairing (annealing). This suggests that BRCA1/CtIP-mediated processing of the second end of the break controls the annealing step that normally terminates SDSA, thereby suppressing the error-prone LTGC outcome.

  7. Ovarian Cancer and BRCA1/2 Testing: Opportunities to improve clinical care and disease prevention

    Directory of Open Access Journals (Sweden)

    Katherine eKarakasis

    2016-05-01

    Full Text Available Without prevention or screening options available, ovarian cancer is the most lethal malignancy of the female reproductive tract. High grade serous ovarian cancer (HGSOC is the most common histologic subtype, and the role of germline BRCA1/2 mutation in predisposition and prognosis is established. Given the targeted treatment opportunities with PARP inhibitors, a predictive role for BRCA1/2 mutation has emerged. Despite recommendations to provide BRCA1/2 testing to all women with histologically confirmed HGSOC, uniform implementation remains challenging. The opportunity to review and revise genetic screening and testing practices will identify opportunities where universal adoption of BRCA1/2 mutation testing will impact and improve treatment of women with ovarian cancer. Improving education and awareness of genetic testing for women with cancer, as well as the broader general community, will help focus much needed attention on opportunities to advance prevention and screening programs in ovarian cancer. This is imperative not only for women with cancer, those at risk of developing cancer, but also for their first-degree relatives. In addition, BRCA1/2 testing may have direct implications for patients with other types of cancers, many which are now being found to have BRCA1/2 involvement.

  8. Estudio de las aneuplodías del cromosoma 17 y deleción del gen tp53 en neoplasias hematológicas por la técnica del fish-bicolor

    Directory of Open Access Journals (Sweden)

    Carlos Mario Muñetón Peña

    2008-12-01

    Full Text Available Las neoplasias hematológicas se caracterizan por presentar una amplia diversidad de alteraciones genéticas. Se analizaron 15 muestras de diferentes tipos de neoplasias hematológicas mediante el FISH, para detectar aneuplodías del cromosoma17 y la deleción del gen TP53. En 11 de las 15 muestras se realizaron análisis cromosómicos por citogenética convencional; 6 de las 11 muestras tenían cariotipo anormal (54.5%, se detectaron 3 translocaciones y 3 mosaicismos. Análisis de FISH en 15 muestras mostró un 26.7% de aneuplodía del cromosoma 17 y un 33.3% con deleción del gen TP53. De los 6 casos con cariotipo anormal, 2 tenían alteraciones por FISH. En 5 casos se detectaron alteraciones cromosómicas por FISH, las cuales no se observaron por citogenética convencional. Solo 3 (20% de las 15 muestras analizadas fueron normales para el análisis cromosómico por citogenética convencional y FISH. En este trabajo se corrobora que la aneuplodía del cromosoma 17 y la deleción del gen TP53 tienen una baja incidencia en las neoplasias hematológicas. Si embargo, el valor pronóstico de estas alteraciones genéticas no esta bien definido.

  9. Benzene-induced mutational pattern in the tumour suppressor gene TP53 analysed by use of a functional assay, the functional analysis of separated alleles in yeast, in human lung cells.

    Science.gov (United States)

    Billet, Sylvain; Paget, Vincent; Garçon, Guillaume; Heutte, Natacha; André, Véronique; Shirali, Pirouz; Sichel, François

    2010-02-01

    Recent concern has centred on the effects of continuous exposure to low concentrations of benzene, both occupationally and environmentally. Although benzene has for a long time been recognised as a carcinogen for humans, its mechanistic pathway remains unclear. Since mutations in the tumour suppressor gene TP53 are the most common genetic alterations involved in human cancer, our objective was to establish the first mutational pattern induced by benzene on the TP53 gene in human type II-like alveolar epithelial A549 cells by using the Functional Analysis of Separated Alleles in Yeast (FASAY). Seventeen mutations linked to benzene exposure were found: 3 one- or two-base deletions, and 14 single nucleotide substitutions (1 nonsense and 13 missense mutations). A>G and G>A transitions were the most prevalent (23.5% for both). Other mutations included A>C transversions and deletions (3/17, 17.6% for both), G>T transversions (2/17, 11.8%) and A>T transversions (1/17, 5.9%). Data arising from this benzene-induced mutational pattern affecting TP53, a critical target gene in human carcinogenesis, have been compared with those reported in human acute myeloid leukaemia, the aetiology of which is clearly linked to benzene exposure, and in experimental benzene-induced carcinoma. This comparison suggests that A>G transition could be a fingerprint of benzene exposure in tumours. Furthermore, our results demonstrate that FASAY is a promising tool for the study of the carcinogenic potency of benzene in the human lung.

  10. Genetic and epigenetic alterations of the LKB1 gene and their associations with mutations in TP53 and EGFR pathway genes in Korean non-small cell lung cancers.

    Science.gov (United States)

    Lee, Su Man; Choi, Jin Eun; Na, Yeon Kyung; Lee, Eun Jin; Lee, Won Kee; Choi, Yi Young; Yoon, Ghil Suk; Jeon, Hyo-Sung; Kim, Dong Sun; Park, Jae Yong

    2013-08-01

    Liver kinase 1 (LKB1) plays a critical barrier role in lung tumorigenesis by controlling initiation, differentiation and metastasis. We searched for genetic and epigenetic alterations of the LKB1 gene in Korean non-small cell lung cancers (NSCLCs) and correlated the results with clinicopathological features. We also investigated the relationship between genetic and epigenetic alterations of LKB1 and mutations in the TP53 gene and epidermal growth factor receptor (EGFR) pathway genes. A total of 159 NSCLCs were analyzed for loss of heterozygosity (LOH) at microsatellite loci D19S886, and D19S878. Mutations and methylation status of LKB1 were examined by direct sequencing and a methylation-specific polymerase chain reaction, respectively. A somatic mutation was found in one of the 159 tumors. LOH and promoter methylation was detected in 19.5% (31/159) and 13.2% (21/159) of the tumors, respectively. Four of the 159 tumors had concomitant LOH and methylation of LKB1. In total, 30.2% of the 159 NSCLCs harbored LKB1 LOH or promoter methylation, which were correlated with down-regulation of gene expression. LKB1 LOH was more frequent in males, smokers, and tumors with a TP53 mutation than in females, never-smokers, and tumors without a TP53 mutation, respectively. However, no significant correlation between LKB1 alterations and mutations in EGFR pathway genes was found. These results suggest that the prevalence of LKB1 genetic and epigenetic alterations in NSCLCs vary depending on patient ethnicity. Our results show that LKB1 alterations often occur simultaneously with mutations in EGFR pathway genes. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

  11. Estudio de las aneuplodías del cromosoma 17 y deleción del gen tp53 en neoplasias hematológicas por la técnica del fish-bicolor

    OpenAIRE

    Carlos Mario Muñetón Peña; Gloria Cecilia Ramírez Gaviria; Juan Carlos Herrera Patiño

    2008-01-01

    Las neoplasias hematológicas se caracterizan por presentar una amplia diversidad de alteraciones genéticas. Se analizaron 15 muestras de diferentes tipos de neoplasias hematológicas mediante el FISH, para detectar aneuplodías del cromosoma17 y la deleción del gen TP53. En 11 de las 15 muestras se realizaron análisis cromosómicos por citogenética convencional; 6 de las 11 muestras tenían cariotipo anormal (54.5%), se detectaron 3 translocaciones y 3 mosaicismos. Análisis de FISH en 15 muestras...

  12. Germline BRCA1 mutations in patients from 84 families with breast and/or ovarian cancers in northern France.

    Science.gov (United States)

    Peyrat, J P; Vennin, P; Hornez, L; Fournier, J; Adenis, C; Bonneterre, J

    1998-02-01

    The BRCA1 gene modification is responsible for an autosomal dominant syndrome of inherited early onset breast and/or ovarian cancer. This gene is estimated to account for almost half of inherited breast cancers and three quarters of inherited breast/ovarian cancers. This suggests that about 1 in every 500 women may carry the BRCA1 mutation. The BRCA1 was isolated by positional cloning in 1994. More than 100 different mutations have been found in the germline of affected individuals. Using systematic sequencing, we looked at BRCA1 germline mutations in 84 patients treated at the Centre Oscar Lambret for breast and/or ovarian cancer who belonged to high-risk families. We found 39 mutations: 22 true mutations inducing modifications of the BRCA1 protein (BRCA1+), six mutations with unknown consequences on the BRCA1 protein, and eleven mutations corresponding to polymorphisms that had been described previously. All the BRCA1+ cases had a HPG3 tumour. The median age of discovery and the receptor positivity percentage are lower in hereditary breast cancer than in the standard population of the breast cancers treated in our centre. Conversely, most of the BRCA1+ patients are without node involvement. This shows that BRCA1 mutations are not always related to parameters thought to indicate a bad prognosis.

  13. BRCA1 deficiency in skin epidermis leads to selective loss of hair follicle stem cells and their progeny

    Science.gov (United States)

    Sotiropoulou, Panagiota A.; Karambelas, Andrea E.; Debaugnies, Maud; Candi, Aurelie; Bouwman, Peter; Moers, Virginie; Revenco, Tatiana; Rocha, Ana Sofia; Sekiguchi, Kiyotoshi; Jonkers, Jos; Blanpain, Cedric

    2013-01-01

    The accurate maintenance of genomic integrity is essential for tissue homeostasis. Deregulation of this process leads to cancer and aging. BRCA1 is a critical mediator of this process. Here, we performed conditional deletion of Brca1 during epidermal development and found that BRCA1 is specifically required for hair follicle (HF) formation and for development of adult HF stem cells (SCs). Mice deficient for Brca1 in the epidermis are hairless and display a reduced number of HFs that degenerate progressively. Surprisingly, the interfollicular epidermis and the sebaceous glands remain unaffected by Brca1 deletion. Interestingly, HF matrix transient amplifying progenitors present increased DNA damage, p53 stabilization, and caspase-dependent apoptosis compared with the interfollicular and sebaceous progenitors, leading to hyperproliferation, apoptosis, and subsequent depletion of the prospective adult HF SCs. Concomitant deletion of p53 and Brca1 rescues the defect of HF morphogenesis and loss of HF SCs. During adult homeostasis, BRCA1 is dispensable for quiescent bulge SCs, but upon their activation during HF regeneration, Brca1 deletion causes apoptosis and depletion of Brca1-deficient bulge SCs. Our data reveal a major difference in the requirement of BRCA1 between different types of epidermal SCs and progenitors and during the different activation stages of adult HF SCs. PMID:23271346

  14. Molecular analysis reveals heterogeneity of mouse mammary tumors conditionally mutant for Brca1

    Directory of Open Access Journals (Sweden)

    Anver Miriam R

    2008-04-01

    Full Text Available Abstract Background Development of therapies for patients with BRCA1 mutations has been hampered by lack of readily available in vitro and in vivo models. We recently showed that transplantation of transgenic mammary tumors as cell suspensions into naïve recipients generates reproducible tumors with remarkable stability of gene expression profile. We examined the expression profiles of original and serially transplanted mammary tumors from Brca1 deficient mice, and tumor derived cell lines to validate their use for preclinical testing and studies of tumor biology. Methods Original tumors, serially transplanted and multiple cell lines derived from Brca1 mammary tumors were characterized by morphology, gene and protein expression, and cell surface markers. Results Gene expression among Brca1 tumors showed more heterogeneity than among previously characterized tumors from MMTV-PyMT and -Wnt1 models. Gene expression data segregated Brca1 tumors into 3 distinct types: basal, mixed luminal, and tumors with epithelial-to-mesenchymal transition (EMT. Serial transplantation of individual tumors and multiple cell lines derived from the original tumors recapitulated the molecular characteristics of each tumor of origin. One tumor had distinct features of EMT and gave rise to cell lines that contained a distinct CD44+/CD24-/low population that may correlate with human breast cancer stem cells. Conclusion Although individual tumors expanded by transplantation maintain the genomic profile of the original tumors, the heterogeneity among Brca1 tumors limits the extent of their use for preclinical testing. However, cell lines offer a robust material for understanding tumor biology and response to therapies driven by BRCA1 deficiency.

  15. BRCA1 and BRCA2 Gene Mutations Screening In Sporadic Breast Cancer Patients In Kazakhstan.

    Directory of Open Access Journals (Sweden)

    Ainur R. Akilzhanova

    2013-05-01

    Full Text Available Background: A large number of distinct mutations in the BRCA1 and BRCA2 genes have been reported worldwide, but little is known regarding the role of these inherited susceptibility genes in breast cancer risk among Kazakhstan women. Aim: To evaluate the role of BRCA1/2 mutations in Kazakhstan women presenting with sporadic breast cancer. Methods: We investigated the distribution and nature of polymorphisms in BRCA1 and BRCA2 entire coding regions in 156 Kazakhstan sporadic breast cancer cases and 112 age-matched controls using automatic direct sequencing. Results: We identified 22 distinct variants, including 16 missense mutations and 6 polymorphisms in BRCA1/2 genes. In BRCA1, 9 missense mutations and 3 synonymous polymorphisms were observed. In BRCA2, 7 missense mutations and 3 polymorphisms were detected. There was a higher prevalence of observed mutations in Caucasian breast cancer cases compared to Asian cases (p<0.05; higher frequencies of sequence variants were observed in Asian controls. No recurrent or founder mutations were observed in BRCA1/2 genes. There were no statistically significant differences in age at diagnosis, tumor histology, size of tumor, and lymph node involvement between women with breast cancer with or without the BRCA sequence alterations. Conclusions: Considering the majority of breast cancer cases are sporadic, the present study will be helpful in the evaluation of the need for the genetic screening of BRCA1/2 mutations and reliable genetic counseling for Kazakhstan sporadic breast cancer patients. Evaluation of common polymorphisms and mutations and breast cancer risk in families with genetic predisposition to breast cancer is ongoing in another current investigation. 

  16. Relationship between nm23H1 genetic instability and clinical pathological characteristics in Chinese digestive system cancer patients

    Institute of Scientific and Technical Information of China (English)

    Yue-Qin Yang; Ji-Cheng Li; Liang Wu; Jin-Xing Chen; Jian-Zhong Sun; Meng Li; Dong-Mei Li; Hai-Ying Lu; Zhi-Hong Su; Xin-Qiu Liu

    2008-01-01

    AIM: To study the relationship between nm23H1 gene genetic instability and its clinical pathological characteristics in Chinese digestive system cancer patients. METHODS: Polymerase chain reaction-single strand conformation polymorphism (PCR-SSCP) was used to analyze the microsatellite instability (MSI) and loss of heterozygosiLy (LOH). Immunohistochemistry was employed to detect the expression of nm23H1. RESULTS: The MSI was higher in TNM stage I + II than in stage ITI + 1V of gastric, colonic and gallbladder carcinomas. The LOH was higher in TNM stage III + IV than in stage I + II of gastric, colonic and hepatocellular carcinomas. Lymphatic metastasis was also observed. The expression of nm23H1 protein was lower in TNM stage III + IV than in stage I + II of these tumors and in patients with lymphatic metastasis.The nm23H1 protein expression was higher in the LOH negative group than in the LOH positive group. CONCLUSION: MSI and LOH may independently control the biological behaviors of digestive system cancers. MSI could serve as an early biological marker of digestive system cancers. Enhanced expression of nm23Ht protein could efficiently inhibit cancer metastasis and improve its prognosis. LOH mostly appears in late digestive system cancer.

  17. Mutation analysis of BRCA1 and BRCA2 genes in Iranian high risk breast cancer families.

    Science.gov (United States)

    Pietschmann, Andrea; Mehdipour, Parvin; Mehdipour, Parvin; Atri, Morteza; Hofmann, Wera; Hosseini-Asl, S Said; Scherneck, Siegfried; Mundlos, Stefan; Peters, Hartmut

    2005-08-01

    Germline mutations in either BRCA1 or BRCA2 genes are responsible for the majority of hereditary breast and ovarian cancers. At present, over thousand distinct BRCA1 and BRCA2 mutations have been identified. Specific mutations are found to be common within particular populations, resulting from genetic founder effects. To investigate the contribution of germline mutations in these two genes to inherited breast cancer in Iran, we performed BRCA1/BRCA2 mutation analyses in ten Iranian high risk breast cancer families. This is the first study analysing the complete coding sequences of both genes that concerns the Iranian population. BRCA1/BRCA2 mutation detection included sequencing of the coding and the 3' and 5' untranslated regions. To detect large genomic rearrangements in the BRCA1 gene semi-quantitative multiplex PCR was performed. Two pathogenic mutations in the BRCA2 gene were detected: a novel deletion c.4415_4418delAGAA and a previously described insertion c.6033_6034insGT. In addition, one intronic variation g.5075-53C > T and a deletion/insertion g.*381_389del9ins29 in the 3' untranslated region of BRCA1 were found in two of the investigated families. Both sequence alterations were absent in an age matched Iranian control group. The BRCA2 homozygous variation p.N372H, previously associated with an increased risk for developing breast cancer, was not identified in this study. We did not detect large genomic rearrangements in BRCA1 in patients tested negatively for disease causing mutations in both genes by standard sequencing. At present, the BRCA2 mutations c.4415_4418delAGAA and c.6033_6034insGT have not been identified in any investigated population except the Iranian. Whether both mutations are specific for the Iranian population or a special subgroup remains to be investigated in larger studies. The absence of BRCA1 mutations in the analysed families may suggest that penetrance or prevalence of BRCA1 mutations may be lower in Iran.

  18. The Role of BRCA1 in Suppressing Epithelial-Mesenchymal Transition in Mammary Gland and Tumor Development

    Science.gov (United States)

    2015-09-01

    Histo- and pathological analysis revealed that, unlike homogeneous and well differentiated T47D-Sh-Ctrl. mammary tumors, T47D-Sh-BRCA1 tumors were...AWARD NUMBER: W81XWH-13-1-0282 TITLE: The Role of BRCA1 in Suppressing Epithelial-Mesenchymal Transition in Mammary Gland and Tumor...2014 - 31 Aug 2015 4. TITLE AND SUBTITLE 5a. CONTRACT NUMBER The Role of BRCA1 in Suppressing Epithelial-Mesenchymal Transition in Mammary Gland and

  19. Prevalence of BRCA1 and BRCA2 mutations in unselected breast cancer patients from Peru

    Science.gov (United States)

    Abugattas, Julio; Llacuachaqui, Marcia; Allende, Yasser Sullcahuaman; Velásquez, Abelardo Arias; Velarde, Raúl; Cotrina, José; Garcés, Milko; León, Mauricio; Calderón, Gabriela; de la Cruz, Miguel; Mora, Pamela; Royer, Robert; Herzog, Josef; Weitzel, Jeffrey N; Narod, Steven A

    2014-01-01

    The prevalence of BRCA1 and BRCA2 mutations among breast cancer patients in Peru has not yet been explored. We enrolled 266 women with breast cancer from a National cancer hospital in Lima, Peru, unselected for age or family history. DNA was screened with a panel of 114 recurrent Hispanic BRCA mutations (HISPANEL). Among the 266 cases, thirteen deleterious mutations were identified (eleven in BRCA1 and two in BRCA2), representing 5% of the total. The average age of breast cancer in the mutation-positive cases was 44 years. BRCA1 185delAG represented seven of the eleven mutations in BRCA1. Other mutations detected in BRCA1 included: two 2080delA, one 943ins10, and one 3878delTA. The BRCA2 3036del4 mutation was seen in two patients. Given the relatively low cost of the HISPANEL test, one should consider offering this test to all Peruvian women with breast or ovarian cancer. PMID:25256238

  20. BRCA1 Is a Histone-H2A-Specific Ubiquitin Ligase

    Directory of Open Access Journals (Sweden)

    Reinhard Kalb

    2014-08-01

    Full Text Available The RING domain proteins BRCA1 and BARD1 comprise a heterodimeric ubiquitin (E3 ligase that is required for the accumulation of ubiquitin conjugates at sites of DNA damage and for silencing at DNA satellite repeat regions. Despite its links to chromatin, the substrate and underlying function of the BRCA1/BARD1 ubiquitin ligase remain unclear. Here, we show that BRCA1/BARD1 specifically ubiquitylates histone H2A in its C-terminal tail on lysines 127 and 129 in vitro and in vivo. The specificity for K127-129 is acquired only when H2A is within a nucleosomal context. Moreover, site-specific targeting of the BRCA1/BARD1 RING domains to chromatin is sufficient for H2Aub foci formation in vivo. Our data establish BRCA1/BARD1 as a histone-H2A-specific E3 ligase, helping to explain its localization and activities on chromatin in cells.

  1. Three-Dimensional Architecture of the Human BRCA1-A Histone Deubiquitinase Core Complex

    Directory of Open Access Journals (Sweden)

    Otto J.P. Kyrieleis

    2016-12-01

    Full Text Available BRCA1 is a tumor suppressor found to be mutated in hereditary breast and ovarian cancer and plays key roles in the maintenance of genomic stability by homologous recombination repair. It is recruited to damaged chromatin as a component of the BRCA1-A deubiquitinase, which cleaves K63-linked ubiquitin chains attached to histone H2A and H2AX. BRCA1-A contributes to checkpoint regulation, repair pathway choice, and HR repair efficiency through molecular mechanisms that remain largely obscure. The structure of an active core complex comprising two Abraxas/BRCC36/BRCC45/MERIT40 tetramers determined by negative-stain electron microscopy (EM reveals a distorted V-shape architecture in which a dimer of Abraxas/BRCC36 heterodimers sits at the base, with BRCC45/Merit40 pairs occupying each arm. The location and ubiquitin-binding activity of BRCC45 suggest that it may provide accessory interactions with nucleosome-linked ubiquitin chains that contribute to their efficient processing. Our data also suggest how ataxia telangiectasia mutated (ATM-dependent BRCA1 dimerization may stabilize self-association of the entire BRCA1-A complex.

  2. Screening of BRCA1/2 Mutations Using Direct Sequencing in Indonesian Familial Breast Cancer Cases.

    Science.gov (United States)

    Anwar, Sumadi Lukman; Haryono, Samuel J; Aryandono, Teguh; Datasena, I Gusti Bagus

    2016-01-01

    Breast cancer has emerged as the most prevalent cancer among women worldwide, including in Indonesia. The contribution of genes associated with high-risk breast-ovarian cancers, BRCA1 and BRCA2, in the Indonesian population is relatively unknown. We have characterized family history of patients with moderate- to high-risk of breast cancer predisposition in 26 unrelated cases from Indonesia for BRCA1/2 mutation analyses using direct sequencing. Known deleterious mutations were not found in either BRCA1 or BRCA2 genes. Seven variants in BRCA2 were documented in 10 of 26 patients (38%). All variants were categorized as unclassified (VUSs). Two synonymous variants, c.3623A>G and c.4035T>C, were found in 5 patients. One variant, c4600T>C, was found in a 38 year old woman with a family history of breast cancer. We have found 4 novel variants in BRCA2 gene including c.6718C>G, c.3281A>G, c.10176C>G, and c4490T>C in 4 unrelated patients, all of them having a positive family history of breast cancer. In accordance to other studies in Asian population, our study showed more frequent variants in BRCA2 compared to BRCA1. Further studies involving larger numbers of hereditary breast cancer patients are required to reveal contribution of BRCA1/2 mutations and/or other predisposing genes among familial breast cancer patients in Indonesia.

  3. Prevalance of BRCA1 and BRCA2 mutations in familial breast cancer patients in Lebanon

    Directory of Open Access Journals (Sweden)

    Jalkh Nadine

    2012-06-01

    Full Text Available Abstract Breast cancer is the most prevalent malignancy in women in Western countries, currently accounting for one third of all female cancers. Familial aggregation is thought to account for 5–10 % of all BC cases, and germline mutations in BRCA1 and BRCA2 account for less of the half of these inherited cases. In Lebanon, breast cancer represents the principal death-causing malignancy among women, with 50 % of the cases diagnosed before the age of 50 years. In order to study BRCA1/2 mutation spectra in the Lebanese population, 72 unrelated patients with a reported family history of breast and/or ovarian cancers or with an early onset breast cancer were tested. Fluorescent direct sequencing of the entire coding region and intronic sequences flanking each exon was performed. A total of 38 BRCA1 and 40 BRCA2 sequence variants were found. Seventeen of them were novel. Seven confirmed deleterious mutations were identified in 9 subjects providing a frequency of mutations of 12.5 %. Fifteen variants were considered of unknown clinical significance according to BIC and UMD-BRCA1/BRCA2 databases. In conclusion, this study represents the first evaluation of the deleterious and unclassified genetic variants in the BRCA1/2 genes found in a Lebanese population with a relatively high risk of breast cancer.

  4. Oral contraceptives and breast cancer risk in the international BRCA1/2 carrier cohort study

    DEFF Research Database (Denmark)

    Brohet, Richard M; Goldgar, David E; Easton, Douglas F

    2007-01-01

    oral contraceptive use and risk of breast cancer among BRCA1/2 carriers. PATIENTS AND METHODS In the International BRCA1/2 Carrier Cohort study (IBCCS), a retrospective cohort of 1,593 BRCA1/2 mutation carriers was analyzed with a weighted Cox regression analysis. Results We found an increased risk...... of breast cancer for BRCA1/2 mutation carriers who ever used oral contraceptives (adjusted hazard ratio [HR] = 1.47; 95% CI, 1.16 to 1.87). HRs did not vary according to time since stopping use, age at start, or calendar year at start. However, a longer duration of use, especially before first full...... was found among BRCA1/2 mutation carriers that current use of oral contraceptives is associated with risk of breast cancer more strongly than is past use, as is found in the general population. However, duration of use, especially before first full-term pregnancy, may be associated with an increasing risk...

  5. Prevalence of BRCA1 and BRCA2 mutations in unselected breast cancer patients from Peru.

    Science.gov (United States)

    Abugattas, J; Llacuachaqui, M; Allende, Y Sullcahuaman; Velásquez, A Arias; Velarde, R; Cotrina, J; Garcés, M; León, M; Calderón, G; de la Cruz, M; Mora, P; Royer, R; Herzog, J; Weitzel, J N; Narod, S A

    2015-10-01

    The prevalence of BRCA1 and BRCA2 mutations among breast cancer patients in Peru has not yet been explored. We enrolled 266 women with breast cancer from a National cancer hospital in Lima, Peru, unselected for age or family history. DNA was screened with a panel of 114 recurrent Hispanic BRCA mutations (HISPANEL). Among the 266 cases, 13 deleterious mutations were identified (11 in BRCA1 and 2 in BRCA2), representing 5% of the total. The average age of breast cancer in the mutation-positive cases was 44 years. BRCA1 185delAG represented 7 of 11 mutations in BRCA1. Other mutations detected in BRCA1 included: two 2080delA, one 943ins10, and one 3878delTA. The BRCA2 3036del4 mutation was seen in two patients. Given the relatively low cost of the HISPANEL test, one should consider offering this test to all Peruvian women with breast or ovarian cancer. © 2014 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  6. Missense polymorphisms in BRCA1 and BRCA2 and risk of breast and ovarian cancer

    DEFF Research Database (Denmark)

    Dombernowsky, Sarah Louise; Weischer, Maren; Freiberg, Jacob Johannes

    2009-01-01

    PURPOSE: BRCA1 and BRCA2 are key tumor suppressors with a role in cellular DNA repair, genomic stability, and checkpoint control. Mutations in BRCA1 and BRCA2 often cause hereditary breast and ovarian cancer; however, missense polymorphisms in these genes pose a problem in genetic counseling.......3 in the prospective study, and above 1.2 to 3.2 in the case-control study. CONCLUSIONS: Heterozygosity and homozygosity of any of the examined nine BRCA1 and BRCA2 missense polymorphisms cannot explain the increased risk of breast and/or ovarian cancer observed in families with hereditary breast and/or ovarian cancer......, as their impact on risk of breast and ovarian cancer is unclear. EXPERIMENTAL DESIGN: We resequenced BRCA1 and BRCA2 in 194 women with a familial history of breast and/or ovarian cancer and identified nine possibly biologically relevant polymorphisms (BRCA1 Gln356Arg, Pro871Leu, Glu1038Gly, Ser1613Gly, and Met...

  7. ZMYM3 regulates BRCA1 localization at damaged chromatin to promote DNA repair.

    Science.gov (United States)

    Leung, Justin W C; Makharashvili, Nodar; Agarwal, Poonam; Chiu, Li-Ya; Pourpre, Renaud; Cammarata, Michael B; Cannon, Joe R; Sherker, Alana; Durocher, Daniel; Brodbelt, Jennifer S; Paull, Tanya T; Miller, Kyle M

    2017-02-01

    Chromatin connects DNA damage response factors to sites of damaged DNA to promote the signaling and repair of DNA lesions. The histone H2A variants H2AX, H2AZ, and macroH2A represent key chromatin constituents that facilitate DNA repair. Through proteomic screening of these variants, we identified ZMYM3 (zinc finger, myeloproliferative, and mental retardation-type 3) as a chromatin-interacting protein that promotes DNA repair by homologous recombination (HR). ZMYM3 is recruited to DNA double-strand breaks through bivalent interactions with both histone and DNA components of the nucleosome. We show that ZMYM3 links the HR factor BRCA1 to damaged chromatin through specific interactions with components of the BRCA1-A subcomplex, including ABRA1 and RAP80. By regulating ABRA1 recruitment to damaged chromatin, ZMYM3 facilitates the fine-tuning of BRCA1 interactions with DNA damage sites and chromatin. Consistent with a role in regulating BRCA1 function, ZMYM3 deficiency results in impaired HR repair and genome instability. Thus, our work identifies a critical chromatin-binding DNA damage response factor, ZMYM3, which modulates BRCA1 functions within chromatin to ensure the maintenance of genome integrity. © 2017 Leung et al.; Published by Cold Spring Harbor Laboratory Press.

  8. Mutações no gene TP53 em tumores malignos de mama: associação com fatores de risco e características clínico-patológicas, inclusive risco de óbito, em pacientes residentes no Rio de Janeiro TP53 mutation in malignant breast tumors: association with risk factors and clinical-pathological characteristics, including risk of death, in patients from Rio de Janeiro

    Directory of Open Access Journals (Sweden)

    Claudia Vitória de Moura-Gallo

    2004-06-01

    Full Text Available No Brasil, o câncer de mama é a primeira causa de óbito por câncer entre mulheres, sendo o Rio de Janeiro o Estado que apresenta o maior coeficiente de mortalidade do país. Estudos que avaliam a sobrevida por câncer de mama têm indicado que vários fatores de ordem genética e molecular podem influenciar a evolução dos casos. O objetivo deste trabalho foi descrever mutações no gene TP53 em 120 pacientes com diagnóstico de carcinoma invasivo de mama, recrutadas no Instituto Nacional de Câncer (INCA, Rio de Janeiro, entre 1995 a 1997, e analisar as possíveis associações entre fatores de risco e presença de mutação e entre características do tumor, incluindo estas mutações e o risco de óbito. A análise molecular detectou 24 mutações no gene TP53 em 22 casos (18,3%, sendo que 2 casos apresentaram 2 mutações cada e, em um caso observamos o polimorfismo no éxon 6. As mutações encontradas eram: 14 com troca de sentido; 2 sem sentido; 2 silenciosas; 2 deleções; 1 inserção e 3 localizadas em íntron. Em relação aos fatores de risco estudados em associação à presença de mutação, observou-se que apenas o consumo de tabaco mostrou associação negativa (OR ajustado= 0,24 (0,06-0,88. A análise multivariada utilizada para avaliar as características tumorais associadas ao risco de óbito mostrou que apenas a agressividade do tumor apresentou OR indicativo de risco (3,98, IC 95% 1,25-12,72. Estes resultados corroboram outros estudos que mostram que a mutação no gene TP53 pode ser um indicador de tumores de mama biologicamente mais agressivos, apesar de não ser o único parâmetro a ser considerado.Breast cancer is the leading cause of death due to cancer among women in Brazil and, the State of Rio de Janeiro presents the highest mortality coefficient of this disease in the country. Studies have shown that many genetic and molecular factors may be related to the outcome of cases. The aim of this study was to

  9. The BRCA1 variant p.Ser36Tyr abrogates BRCA1 protein function and potentially confers a moderate risk of breast cancer.

    Directory of Open Access Journals (Sweden)

    Charita M Christou

    Full Text Available The identification of variants of unknown clinical significance (VUS in the BRCA1 gene complicates genetic counselling and causes additional anxiety to carriers. In silico approaches currently used for VUS pathogenicity assessment are predictive and often produce conflicting data. Furthermore, functional assays are either domain or function specific, thus they do not examine the entire spectrum of BRCA1 functions and interpretation of individual assay results can be misleading. PolyPhen algorithm predicted that the BRCA1 p.Ser36Tyr VUS identified in the Cypriot population was damaging, whereas Align-GVGD predicted that it was possibly of no significance. In addition the BRCA1 p.Ser36Tyr variant was found to be associated with increased risk (OR = 3.47, 95% CI 1.13-10.67, P = 0.02 in a single case-control series of 1174 cases and 1109 controls. We describe a cellular system for examining the function of exogenous full-length BRCA1 and for classifying VUS. We achieved strong protein expression of full-length BRCA1 in transiently transfected HEK293T cells. The p.Ser36Tyr VUS exhibited low protein expression similar to the known pathogenic variant p.Cys61Gly. Co-precipitation analysis further demonstrated that it has a reduced ability to interact with BARD1. Further, co-precipitation analysis of nuclear and cytosolic extracts as well as immunofluorescence studies showed that a high proportion of the p.Ser36Tyr variant is withheld in the cytoplasm contrary to wild type protein. In addition the ability of p.Ser36Tyr to co-localize with conjugated ubiquitin foci in the nuclei of S-phase synchronized cells following genotoxic stress with hydroxyurea is impaired at more pronounced levels than that of the p.Cys61Gly pathogenic variant. The p.Ser36Tyr variant demonstrates abrogated function, and based on epidemiological, genetic, and clinical data we conclude that the p.Ser36Tyr variant is probably associated with a moderate breast cancer risk.

  10. Síndrome de cáncer de mama/ovario hereditario: desarrollo de una guía clínica y análisis de los genes ATM, TP53 en familias de alto riesgo para cáncer de mama no asociado a BRCA1 y/o BRCA2

    OpenAIRE

    Graña Suárez, Begoña

    2013-01-01

    El cáncer de mama hereditario (CMH) es genéticamente muy heterogéneo. Los genes de predisposición conocidos hasta el momento explican menos del 40% del riesgo familiar observado. El estudio de los principales genes implicados en el CMH ha sido el objetivo de esta Tesis Doctoral que se presenta en formato de artículos publicados en revistas indexadas. El primer trabajo es una guía clínica sobre cáncer hereditario de referencia a nivel nacional en la que se discuten los aspect...

  11. Identification and analysis of cDNAs encoding two nucleoside diphosphate kinases (NDPK/Nm23) from the marine sponge Suberites domuncula

    OpenAIRE

    Harcet, Matija; Lukić-Bilela, Lada; Ćetković, Helena; Müller, E.G. Werner; Gamulin, Vera

    2005-01-01

    Suberites domuncula is a member of the most ancient and simplest extant phylum of multicellular animals - sponges (Porifera). A database of S. domuncula expressed sequence tags (ESTs) was recently constructed by random cDNA sequencing. Two NDPK/Nm23 proteins from the sponge Suberites domuncula are reported here. Sponge proteins were named Nm23-SD1 and Nm23-SD6, because they display the highest sequence similarity with human Nm23-H1 and -H6 proteins. Overall sequence conservation of Nm23-SD1 w...

  12. Risks of Breast, Ovarian, and Contralateral Breast Cancer for BRCA1 and BRCA2 Mutation Carriers.

    Science.gov (United States)

    Kuchenbaecker, Karoline B; Hopper, John L; Barnes, Daniel R; Phillips, Kelly-Anne; Mooij, Thea M; Roos-Blom, Marie-José; Jervis, Sarah; van Leeuwen, Flora E; Milne, Roger L; Andrieu, Nadine; Goldgar, David E; Terry, Mary Beth; Rookus, Matti A; Easton, Douglas F; Antoniou, Antonis C; BRCA1 and BRCA2 Cohort Consortium; McGuffog, Lesley; Evans, D Gareth; Barrowdale, Daniel; Frost, Debra; Adlard, Julian; Ong, Kai-Ren; Izatt, Louise; Tischkowitz, Marc; Eeles, Ros; Davidson, Rosemarie; Hodgson, Shirley; Ellis, Steve; Nogues, Catherine; Lasset, Christine; Stoppa-Lyonnet, Dominique; Fricker, Jean-Pierre; Faivre, Laurence; Berthet, Pascaline; Hooning, Maartje J; van der Kolk, Lizet E; Kets, Carolien M; Adank, Muriel A; John, Esther M; Chung, Wendy K; Andrulis, Irene L; Southey, Melissa; Daly, Mary B; Buys, Saundra S; Osorio, Ana; Engel, Christoph; Kast, Karin; Schmutzler, Rita K; Caldes, Trinidad; Jakubowska, Anna; Simard, Jacques; Friedlander, Michael L; McLachlan, Sue-Anne; Machackova, Eva; Foretova, Lenka; Tan, Yen Y; Singer, Christian F; Olah, Edith; Gerdes, Anne-Marie; Arver, Brita; Olsson, Håkan

    2017-06-20

    The clinical management of BRCA1 and BRCA2 mutation carriers requires accurate, prospective cancer risk estimates. To estimate age-specific risks of breast, ovarian, and contralateral breast cancer for mutation carriers and to evaluate risk modification by family cancer history and mutation location. Prospective cohort study of 6036 BRCA1 and 3820 BRCA2 female carriers (5046 unaffected and 4810 with breast or ovarian cancer or both at baseline) recruited in 1997-2011 through the International BRCA1/2 Carrier Cohort Study, the Breast Cancer Family Registry and the Kathleen Cuningham Foundation Consortium for Research into Familial Breast Cancer, with ascertainment through family clinics (94%) and population-based studies (6%). The majority were from large national studies in the United Kingdom (EMBRACE), the Netherlands (HEBON), and France (GENEPSO). Follow-up ended December 2013; median follow-up was 5 years. BRCA1/2 mutations, family cancer history, and mutation location. Annual incidences, standardized incidence ratios, and cumulative risks of breast, ovarian, and contralateral breast cancer. Among 3886 women (median age, 38 years; interquartile range [IQR], 30-46 years) eligible for the breast cancer analysis, 5066 women (median age, 38 years; IQR, 31-47 years) eligible for the ovarian cancer analysis, and 2213 women (median age, 47 years; IQR, 40-55 years) eligible for the contralateral breast cancer analysis, 426 were diagnosed with breast cancer, 109 with ovarian cancer, and 245 with contralateral breast cancer during follow-up. The cumulative breast cancer risk to age 80 years was 72% (95% CI, 65%-79%) for BRCA1 and 69% (95% CI, 61%-77%) for BRCA2 carriers. Breast cancer incidences increased rapidly in early adulthood until ages 30 to 40 years for BRCA1 and until ages 40 to 50 years for BRCA2 carriers, then remained at a similar, constant incidence (20-30 per 1000 person-years) until age 80 years. The cumulative ovarian cancer risk to age 80 years was 44

  13. Tolerance for uncertainty and perceived risk among women receiving uninformative BRCA1/2 test results.

    Science.gov (United States)

    O'Neill, Suzanne C; DeMarco, Tiffani; Peshkin, Beth N; Rogers, Sarah; Rispoli, Jessica; Brown, Karen; Valdimarsdottir, Heiddis; Schwartz, Marc D

    2006-11-15

    Women who receive uninformative BRCA1/2 genetic test results face ongoing uncertainty about their future cancer risks. This article prospectively examined the influence of intolerance for uncertainty and perceived breast cancer risk on psychological distress following the receipt of uninformative BRCA1/2 test results. Sixty-four women who received uninformative BRCA1/2 mutation test results completed measures of Intolerance for Uncertainty, perceived breast cancer risk, and measures of cancer-related, genetic testing, and general distress. Cancer-related (DeltaR(2) = 0.18, P uncertainty at 1 month post-disclosure. The interaction of intolerance for uncertainty and breast cancer perceived risk predicted cancer-related (DeltaR(2) = 0.10, P uncertainty, suggesting that those who have difficulty coping with their ambiguous risk are at risk for long-term distress. The clinical and research implications of these results are discussed. (c) 2006 Wiley-Liss, Inc.

  14. BRCA 1/2-mutation related and sporadic breast and ovarian cancers: More alike than different

    Directory of Open Access Journals (Sweden)

    Melissa A. Burgess

    2014-02-01

    Full Text Available No longer is histology solely predictive of cancer treatment and outcome. There is an increasing influence of tumor genomic characteristics on therapeutic options. Both breast and ovarian cancers are at higher risk of development in patients with BRCA 1/2-germline mutations. Recent data from the Cancer Genome Atlas (TCGA and others have shown a number of genomic similarities between triple negative breast cancers and ovarian cancers. Recently, poly (ADP-ribose polymerase (PARP inhibitors have shown promising activity in hereditary BRCA 1/2-mutated and sporadic breast and ovarian cancers. In this review, we will summarize the current literature regarding the genomic and phenotypic similarities between BRCA 1/2-mutation related cancers, sporadic triple negative breast cancers, and sporadic ovarian cancers. We will also review phase I, II, and III data using PARP inhibitors for these malignancies and compare and contrast the results with respect to histology.

  15. The prevalence of BRCA1 mutations among young women with triple-negative breast cancer

    Science.gov (United States)

    2009-01-01

    Background Molecular screening for BRCA1 and BRCA2 mutations is now an established component of risk evaluation and management of familial breast cancer. Features of hereditary breast cancer include an early age-of-onset and over-representation of the 'triple-negative' phenotype (negative for estrogen-receptor, progesterone-receptor and HER2). The decision to offer genetic testing to a breast cancer patient is usually based on her family history, but in the absence of a family history of cancer, some women may qualify for testing based on the age-of-onset and/or the pathologic features of the breast cancer. Methods We studied 54 women who were diagnosed with high-grade, triple-negative invasive breast cancer at or before age 40. These women were selected for study because they had little or no family history of breast or ovarian cancer and they did not qualify for genetic testing using conventional family history criteria. BRCA1 screening was performed using a combination of fluorescent multiplexed-PCR analysis, BRCA1 exon-13 6 kb duplication screening, the protein truncation test (PTT) and fluorescent multiplexed denaturing gradient gel electrophoresis (DGGE). All coding exons of BRCA1 were screened. The two large exons of BRCA2 were also screened using PTT. All mutations were confirmed with direct sequencing. Results Five deleterious BRCA1 mutations and one deleterious BRCA2 mutation were identified in the 54 patients with early-onset, triple-negative breast cancer (11%). Conclusion Women with early-onset triple-negative breast cancer are candidates for genetic testing for BRCA1, even in the absence of a family history of breast or ovarian cancer. PMID:19298662

  16. Breast imaging findings in women with BRCA1- and BRCA2-associated breast carcinoma

    Energy Technology Data Exchange (ETDEWEB)

    Hamilton, L.J.; Evans, A.J. E-mail: aevans@ncht.trent.nhs.uk; Wilson, A.R.M.; Scott, N.; Cornford, E.J.; Pinder, S.E.; Khan, H.N.; Macmillan, R.D

    2004-10-01

    AIM: To document the breast imaging findings of women with BRCA1 and BRCA2-associated breast carcinoma. MATERIALS AND METHODS: Family history clinic records identified 18 BRCA1 and 10 BRCA2 cases who collectively were diagnosed with 27 invasive breast carcinomas and four ductal carcinoma in situ (DCIS) lesions. All underwent pre-operative imaging (29 mammogram and 22 ultrasound examinations). All invasive BRCA-associated breast carcinoma cases were compared with age-matched cases of sporadic breast carcinoma. RESULTS: Within the BRCA cases the age range was 26-62 years, mean 36 years. Two mammograms were normal and 27 (93%) abnormal. The most common mammographic features were defined mass (63%) and microcalcifications (37%). Thirty-four percent of women had a dense mammographic pattern, 59% mixed and 7% fatty. Ultrasound was performed in 22 patients and in 21 (95%) indicated a mass. This was classified as benign in 24%, indeterminate in 29% and malignant in 48%. Mammograms of BRCA1-associated carcinomas more frequently showed a defined mass compared with BRCA2-associated carcinomas, 72 versus 36% (73% control group) whilst mammograms of BRCA2-associated carcinomas more frequently showed microcalcification, 73 versus 12% (8% control group; p<0.001). Thirty-six percent of the BRCA2-associated carcinomas were pure DCIS while none of the BRCA1 associated carcinomas were pure DCIS (p=0.004). Of those patients undergoing regular mammographic screening, 100% of BRCA2-associated carcinomas were detected compared with 75% of BRCA1-associated carcinomas. CONCLUSION: These data suggest that the imaging findings of BRCA1 and BRCA2-associated carcinomas differ from each other and from age-matched cases of sporadic breast carcinoma.

  17. Role of BRCA1 in Controlling Mitotic Arrest in Ovarian Cystadenoma Cells

    Science.gov (United States)

    Yu, Vanessa M.; Marion, Christine M.; Austria, Theresa M.; Yeh, Jennifer; Schönthal, Axel H.; Dubeau, Louis

    2011-01-01

    Cancers that develop in BRCA1 mutation carriers are usually near tetraploid/polyploid. This led us to hypothesize that BRCA1 controls the mitotic checkpoint complex, as loss of such control could lead to mitotic errors resulting in tetraploidy/polyploidy with subsequent aneuploidy. We used an in vitro system mimicking pre-malignant conditions, consisting of cell strains derived from the benign counterparts of serous ovarian carcinomas (cystadenomas) and expressing SV40 large T antigen, conferring the equivalent of a p53 mutation. We previously showed that such cells undergo one or several doublings of their DNA content as they age in culture and approach the phenomenon of in vitro crisis. Here we show that such increase in DNA content reflects a cell cycle arrest possibly at the anaphase promoting complex, as evidenced by decreased BrdU incorporation and increased expression of the mitotic checkpoint complex. Down-regulation of BRCA1 in cells undergoing crisis leads to activation of the anaphase promoting complex and resumption of growth kinetics similar to those seen in cells before they reach crisis. Cells recovering from crisis after BRCA1 down-regulation become multinucleated, suggesting that reduced BRCA1 expression may lead to initiation of a new cell cycle without completion of cytokinesis. This is the first demonstration that BRCA1 controls a physiological arrest at the M phase apart from its established role in DNA damage response, a role that could represent an important mechanism for acquisition of aneuploidy during tumor development. This may be particularly relevant to cancers that have a near tetraploid/polyploid number of chromosomes. PMID:21792894

  18. The prevalence of BRCA1 mutations among young women with triple-negative breast cancer

    Directory of Open Access Journals (Sweden)

    DeSai Damini

    2009-03-01

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