Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Pivot Concepts:
Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Target Concepts:
Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Query: UNIPROT:P43146 (
tumour suppressor
)
5,935
document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)
Breast cancer is the most prevalent disease and second leading cause of death among women in many countries. Mutations and consequent DNA damage in several genes such as oncogenes and
tumour suppressor
genes have been implicated with abnormal behavior of somatic cells, resulting into malignant growth termed cancer. DNA damage/changes in chromosomal DNA and failure of DNA repair mechanism are important factors for cancer causation. Aberrant behavior of cells leading to uncontrolled proliferation causing cancer is attributable to amplicon formation, large deletions in some genes, mutations, and recombination breakpoints etc. which cause aberrant gene expression. Several patented genes found to be associated with breast cancer, have been discussed, such as BRCA1,
BRCA2
, DAP kinase, MYH, BCSGs, BCW 2 and Id-2 etc. Several of the genes/markers associated with breast cancer can be considered as appropriate candidates for developing early detection systems/protocols for breast cancer.
...
PMID:Recent patents on genes and gene sequences useful for developing breast cancer detection systems. 1951 84
Germline mutations in the
BRCA2
tumour suppressor
gene are significant risk indicators of breast cancer in women, especially for hereditary breast cancer. The BRCA2 protein interacts via the BRC (breast cancer) domain with RAD51, an essential component of the cellular machinery for the maintenance of genome stability and double strand-breaks repair. Exon 11 is the largest exon of the
BRCA2
gene and contains the region encoding eight repeats of the BRC domain. Little is known about the roles of
BRCA2
exon 11 in canine mammary tumours. In present study, the entire
BRCA2
exon 11 was sequenced in canine mammary tumours. Fifteen mammary gland samples were obtained from four normal mammary glands and 11 mammary tumours (10 malignant and one benign tumours). Comparing sequences of normal mammary glands with those in GenBank (AB043895 and Z75664), a single nucleotide polymorphism (SNP) at codon 2414 G>A (resulting in a lysine to an arginine substitution) was identified. When compared with the normal mammary gland, 19 sporadically distributed point mutations were found in mammary tumours, including 68% of missense and 32% of silent mutations. A high frequency of genetic variations in codon 511 A>C or 2414 A>G were identified in 6/11 cases, and two missense mutations (2414 A>G, 2383 A>C) were located at the fourth repeat of the BRC domains.
...
PMID:Single nucleotide variation in exon 11 of canine BRCA2 in healthy and cancerous mammary tissue. 1994 33
Extensive expression profiling studies have shown that sporadic breast cancer is composed of five clinically relevant molecular subtypes. However, although BRCA1-related tumours are known to be predominantly basal-like, there are few published data on other classes of familial breast tumours. We analysed a cohort of 75 BRCA1,
BRCA2
and non-BRCA1/2 breast tumours by gene expression profiling and found that 74% BRCA1 tumours were basal-like, 73% of
BRCA2
tumours were luminal A or B, and 52% non-BRCA1/2 tumours were luminal A. Thirty-four tumours were also analysed by single nucleotide polymorphism-comparative genomic hybridization (SNP-CGH) arrays. Copy number data could predict whether a tumour was basal-like or luminal with high accuracy, but could not predict its mutation class. Basal-like BRCA1 and basal-like non-BRCA1 tumours were very similar, and contained the highest number of chromosome aberrations. We identified regions of frequent gain containing potential driver genes in the basal (8q and 12p) and luminal A tumours (1q and 17q). Regions of homozygous loss associated with decreased expression of potential
tumour suppressor
genes were also detected, including in basal tumours (5q and 9p), and basal and luminal tumours (10q). This study highlights the heterogeneity of familial tumours and the clinical consequences for treatment and prognosis.
...
PMID:Subtypes of familial breast tumours revealed by expression and copy number profiling. 1996 Feb 44
The
tumour suppressor
gene, phosphatase and tensin homolog (PTEN), is one of the most commonly mutated genes in human cancers. Recent evidence suggests that PTEN is important for the maintenance of genome stability. Here, we show that PTEN deficiency causes a homologous recombination (HR) defect in human tumour cells. The HR deficiency caused by PTEN deficiency, sensitizes tumour cells to potent inhibitors of the DNA repair enzyme poly(ADP-ribose) polymerase (PARP), both in vitro and in vivo. PARP inhibitors are now showing considerable promise in the clinic, specifically in patients with mutations in either of the breast cancer susceptibility genes BRCA1 or
BRCA2
. The data we present here now suggests that the clinical assessment of PARP inhibitors should be extended beyond those with BRCA mutations to a larger group of patients with PTEN mutant tumours.
...
PMID:Synthetic lethal targeting of PTEN mutant cells with PARP inhibitors. 2004 32
Inactivation or loss of the
tumour suppressor
Ras associated domain family 1 isoform A (RASSF1A) allele has been described in breast cancer. Recently, a missense polymorphism predicting p.A331S in RASSF1A was associated with an increased risk of breast cancer and early-onset breast cancer in BRCA1 and
BRCA2
mutation carriers. We genotyped p.A331S RASSF1A in 854 independent, familial, white breast cancer patients (645 BRCA mutation negative, 119 BRCA1 and 90
BRCA2
positive) and compared the genotype in 331 healthy women. The RASSF1A p.A331S variant was not more common in the familial breast cancer cases than in the controls (P = 0.27). Subset analysis demonstrated no association in the BRCA1 (P = 0.26),
BRCA2
(P = 0.16) or BRCA negative (P = 0.30) samples. Hence, the RASSF1A p.A331S polymorphism is not confirmed as a significant germline contributor to familial breast cancer susceptibility.
...
PMID:RASSF1A polymorphism in familial breast cancer. 2036 Dec 64
Germ-line mutations in the
tumour suppressor
proteins BRCA1 and
BRCA2
predispose to breast and ovarian cancer. We have recently identified a Greenlandic Inuit BRCA1 nucleotide 234T>G/c.115T>G (p.Cys39Gly) founder mutation, which at that time was the only disease-causing BRCA1/
BRCA2
mutation identified in this population. Here, we describe the identification of a novel disease-causing BRCA1 nucleotide 4803delCC/c.4684delCC mutation in a Greenlandic Inuit with ovarian cancer. The mutation introduces a frameshift and a premature stop at codon 1572. We have also identified a BRCA1 nucleotide 249T>A/c.130T>A (p.Cys44Ser) mutation in another Greenlandic individual with ovarian cancer. This patient share a 1-2 Mb genomic fragment, containing the BRCA1 gene, with four Danish families harbouring the same mutation, suggesting that the 249T>A/c.130T>A (p.Cys44Ser) mutation originates from a Danish ancestor. We conclude that screening of Greenlandic Inuits with high risk of breast or ovarian cancer should include sequencing of the entire BRCA1 gene.
...
PMID:Identification of a novel BRCA1 nucleotide 4803delCC/c.4684delCC mutation and a nucleotide 249T>A/c.130T>A (p.Cys44Ser) mutation in two Greenlandic Inuit families: implications for genetic screening of Greenlandic Inuit families with high risk for breast and/or ovarian cancer. 2043 99
Epidemiological studies have shown that one of the strongest risk factors for prostate cancer is a family history of the disease, suggesting that inherited factors play a major role in prostate cancer susceptibility. Germline mutations in
BRCA2
predispose to breast and ovarian cancer with its predominant
tumour suppressor
function thought to be the repair of DNA double-strand breaks.
BRCA2
has also been implicated in prostate cancer etiology, but it is unclear the impact that mutations in this gene have on prostate tumourigenesis. Here we have undertaken a genetic analysis in the mouse to determine the role of Brca2 in the adult prostate. We show that deletion of Brca2 specifically in prostate epithelia results in focal hyperplasia and low-grade prostate intraepithelial neoplasia (PIN) in animals over 12 months of age. Simultaneous deletion of Brca2 and the
tumour suppressor
Trp53 in prostate epithelia gave rise to focal hyperplasia and atypical cells at 6 months, leading to high-grade PIN in animals from 12 months. Epithelial cells in these lesions show an increase in DNA damage and have higher levels of proliferation, but also elevated apoptosis. Castration of Brca2;Trp53 mutant animals led to regression of PIN lesions, but atypical cells persisted that continued to proliferate and express nuclear androgen receptor. This study provides evidence that Brca2 can act as a
tumour suppressor
in the prostate, and the model we describe should prove useful in the development of new therapeutic approaches.
...
PMID:Brca2 and Trp53 deficiency cooperate in the progression of mouse prostate tumourigenesis. 2058 17
Germ-line mutations in the
tumour suppressor
genes BRCA1 and
BRCA2
predispose to breast and ovarian cancer. Since 1999 we have performed mutational screening of breast and/or ovarian cancer patients in East Denmark. During this period we have identified 40 novel sequence variations in BRCA1 and
BRCA2
in high risk breast and/or ovarian cancer families. The mutations were detected via pre-screening using dHPLC or high-resolution melting and direct sequencing. We identified 16 variants in BRCA1, including 9 deleterious frame-shift mutations, 2 intronic variants, 4 missense mutations, and 1 synonymous variant. The remaining 24 variants were identified in
BRCA2
, including 10 deleterious mutants (6 frame-shift and 4 nonsense), 2 intronic variants, 10 missense mutations and 2 synonymous variants. The frequency of the variants of unknown significance was examined in control individuals. Moreover, the presumed significance of the missense mutations was predicted in silico using the align GVGD algorithm. In conclusion, the mutation screening identified 40 novel variants in the BRCA1 and
BRCA2
genes and thereby extends the knowledge of the BRCA1/
BRCA2
mutation spectrum. Nineteen of the mutations were interpreted as pathogenic, 3 missense mutations were suggested to be pathogenic based on in silico analysis, 6 mutations were suggested to be benign since they were identified in patients together with a well-known disease-causing BRCA1/
BRCA2
mutation, while 12 were variants of unknown significance.
...
PMID:Screening of 1331 Danish breast and/or ovarian cancer families identified 40 novel BRCA1 and BRCA2 mutations. 2131 80
Hereditary cancer syndromes are frequently seen in young cancer patients and patients with a positive family history. Genetic testing is important for the identification of high-risk individuals, and for the early introduction of specialized preventive care or prophylactic surgeries. High-risk
tumour suppressor
genes (BRCA1 and
BRCA2
) and DNA repair genes (MLH1, MSH2 and MSH6) are responsible for a substantial part of hereditary breast, ovarian and colorectal cancer. Other hereditary cancers are seen less frequently, but genetic testing has increased for many other site-specific cancers and complex syndromes. Genetic centres and molecular genetic laboratories are located mostly within university or regional hospitals. Some genetic centres are private. It is highly recommended (Czech Society for Medical Genetics) that all laboratories are accredited according to ISO 15,189 and that genetic testing of hereditary cancer syndromes is indicated by medical geneticists. The indication criteria and prevention strategies were published in Supplement 22 of Clinical Oncology 2009 (in Czech). Preventive care for high-risk individuals is organized by thirteen Oncology Centres, which provide most of the oncology care in the Czech Republic. Genetic testing and preventive care for high-risk individuals and mutation carriers is covered by health insurance. The molecular genetic laboratory at the MMCI provides molecular genetic testing of BRCA1,
BRCA2
, CHEK2 for hereditary breast/ovarian cancer, MLH1, MSH2, MSH6 for Lynch syndrome,TP53 for Li-Fraumeni syndrome, CDKN2A for familial malignant melanoma syndrome and CDH1 gene for hereditary diffuse gastric cancer. Other syndromes are tested in specialized laboratories elsewhere.The use of genetic testing is increasing because of more frequent referrals from oncologists and other specialists and the increasing variety of genes tested. However, in some patients the testing is not recommended and other family members are dying because of the late diagnosis of hereditary syndrome. Greater awareness of the importance of genetic testing in oncology is needed.
...
PMID:Genetic testing and prevention of hereditary cancer at the MMCI--over 10 years of experience. 2134 12
Epigenetic changes are considered to be a frequent event during tumour development. Hypermethylation of promoter CpG islands represents an alternative mechanism to inactivate
tumour suppressor
genes, DNA repair genes, cell cycle regulators and transcription factors. In search of epigenetic events related to progression, we used MS-MLPA (ME-0002-B1, MRC-Holland, Amsterdam, The Netherlands) to compare the methylation status of 25 breast cancer-related genes between laser-microdissected ductal carcinoma in situ (DCIS) and adjacent invasive ductal cancer (IDC) lesions in 33 breast cancer patients. Using absolute methylation percentages or, alternatively, a 15% cut-off for methylation, promoter methylation in DCIS and IDC was not significantly different for any of the genes studied. Aberrant methylation in at least 50% of both the DCIS and adjacent IDC lesions was observed for PAX6,
BRCA2
, PAX5, WT1, CDH13 and MSH6. Methylation of MSH6, however, was also frequent in normal breast tissue. In contrast, CDKN2A, CHFR, PYCARD and one of the two analysed RB1 CpG loci were rarely (<5%) methylated in both lesions. CDKN2A and GSTP1 showed significantly (p < 0.002) higher mean methylation levels in increasing grades (I, II, III) of DCIS (1% versus 4% versus 7% for CDKN2A and 6% versus 26% versus 28% for GSTP1). The mean number of methylated genes per sample increased with increasing grades of DCIS (p = 0.014) and IDC (p = 0.109). In contrast to the observations in DCIS, none of the analysed genes showed significantly higher methylation levels with increasing grades of IDC. In conclusion, there were no differences in promoter methylation between DCIS and IDC in the 25 analysed genes, suggesting that DCIS, at the epigenetic level, is as advanced as IDC. Promoter hypermethylation of PAX6,
BRCA2
, PAX5, WT1, CDH13 and MSH6 seems to be a frequent early event in breast cancer and methylation levels of GSTP1 (and CDKN2A, although still low) seem to increase with increasing DCIS grade.
...
PMID:Frequent promoter hypermethylation of BRCA2, CDH13, MSH6, PAX5, PAX6 and WT1 in ductal carcinoma in situ and invasive breast cancer. 2171 Jun 92
<< Previous
1
2
3
4
5
6
7
8
9
Next >>