Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0476089 (endometrial cancer)
11,379 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Hereditary non-polyposis colorectal carcinoma (HNPCC) is an autosomal dominant disorder associated with colorectal and endometrial cancer and a range of other tumor types. Germline mutations in the DNA mismatch repair (MMR) genes, particularly MLH1, MSH2, and MSH6, underlie this disorder. The vast majority of these HNPCC-associated mutations have been proven, or assumed, given the family history of cancer, to be transmitted through several generations. To the best of our knowledge, only a single case of a de novo germline MMR gene mutation (in MSH2) has been reported till now. Here, we report a patient with a de novo mutation in MLH1. We identified a MLH1 Q701X truncating mutation in the blood lymphocytes of a male who had been diagnosed with rectal cancer at the age of 35. His family history of cancer was negative for the first- and second-degree relatives. The mutation could not be detected in the patient' parents and sibling and paternity was confirmed with a set of highly polymorphic markers. Non-penetrance and small family size is the common explanation of verified negative family histories of cancer in patients with a germline MMR gene mutation. However, in addition to some cases explained by non-paternity, de novo germline mutations should be considered as a possible explanation as well. As guidelines that stress not to restrict MMR gene mutation testing to patients with a positive family history are more widely introduced, more cases of de novo MMR gene germline mutations may be revealed.
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PMID:First report of a de novo germline mutation in the MLH1 gene. 1652 Dec 1

Hereditary nonpolyposis colorectal cancer (HNPCC) is an inherited syndrome of cancer susceptibility caused by germ line mutations of genes participating in mismatch repair (MMR). Carriers of MMR gene mutations have an increased risk of colorectal cancers and cancer of other organs. Tumors of the endometrium represent the most frequent extracolonic malignancies in HNPCC. It has been suggested that women harboring MMR gene mutations have a higher risk of endometrial cancer than of colon cancer. Here, we describe an HNPCC patient with early-onset endometrial cancer and a strong familial history of endometrial tumors who harbored a germ line MSH2 splice site mutation (IVS9_2A>G). This mutation was responsible for abnormal messenger RNA processing, leading to the introduction of a premature stop signal and to the expression of a truncated MSH2 protein. In addition, the same mutation was associated with loss of MSH2 protein expression, high microsatellite instability, and PTEN inactivation. Although a direct relationship between the endometrial cancer susceptibility and the MSH2 mutation we found cannot be established, our observations, consistent with the work of other authors, suggest the involvement of germ line MSH2 abnormalities in endometrial tumor development and support the case for endometrial cancer screening in women from HNPCC families.
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PMID:MSH2 splice site mutation and endometrial cancer. 1680 40

MLH3 is a recently described member of the DNA mismatch repair gene family. Based on its interaction with the MutL homologue MLH1, it was postulated that MLH3 might play a role in tumorigenesis. Germ line and somatic mutations in MLH3 have been identified in a small fraction of colorectal cancers, but the role of MLH3 in colorectal cancer tumorigenesis remains controversial. We investigated MLH3's role in endometrial tumorigenesis through analysis of tumor and germ line DNA from 57 endometrial cancer patients who were at increased risk for having inherited cancer susceptibility. Patients with known MSH2 or MSH6 mutations were excluded as well as those who had MLH1-methylated tumors. Sixteen different variants were identified by single-strand conformational variant analysis. Of the 12 missense changes identified, three were somatic mutations. One patient had a germ line missense variant and loss of heterozygosity (LOH) in her tumor specimen. There was no evidence of MLH3 promoter methylation based on combined bisulfite restriction analysis. The identification of inherited missense variants, somatic missense mutations (present in 3 of 57 tumors), and LOH in the tumor from a patient with a germ line missense change suggest a role for MLH3 in endometrial tumorigenesis.
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PMID:MLH3 mutation in endometrial cancer. 1688 47

Endometrial cancer is the most common cancer in women with Lynch syndrome. The identification of individuals with Lynch syndrome is desirable because they can benefit from increased cancer surveillance. The purpose of this study was to determine the feasibility and desirability of molecular screening for Lynch syndrome in all endometrial cancer patients. Unselected endometrial cancer patients (N = 543) were studied. All tumors underwent microsatellite instability (MSI) testing. Patients with MSI-positive tumors underwent testing for germ line mutations in MLH1, MSH2, MSH6, and PMS2. Of 543 tumors studied, 118 (21.7%) were MSI positive (98 of 118 MSI high and 20 of 118 MSI low). All 118 patients with MSI-positive tumors had mutation testing, and nine of them had deleterious germ line mutations (one MLH1, three MSH2, and five MSH6). In addition, one case with an MSI-negative tumor had abnormal MSH6 immunohistochemical staining and was subsequently found to have a mutation in MSH6. Immunohistochemical staining was consistent with the mutation result in all seven truncating mutation-positive cases but was not consistent in two of the three missense mutation cases. We conclude that in central Ohio, at least 1.8% (95% confidence interval, 0.9-3.5%) of newly diagnosed endometrial cancer patients had Lynch syndrome. Seven of the 10 Lynch syndrome patients did not meet any published criteria for hereditary nonpolyposis colorectal cancer, and six of them were diagnosed at age >50. Studying all endometrial cancer patients for Lynch syndrome using a combination of MSI and immunohistochemistry for molecular prescreening followed by gene sequencing and deletion analysis is feasible and may be desirable.
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PMID:Screening for Lynch syndrome (hereditary nonpolyposis colorectal cancer) among endometrial cancer patients. 1790 73

Women with germ-line mutations in the mismatch repair genes (responsible for hereditary nonpolyposis colorectal cancer) face an increased risk of colonic and endometrial cancer. However, these germ-line mutations are rare and are responsible for fewer than 1% of endometrial cancers. Therefore, we examined whether or not common variants of the hereditary nonpolyposis colorectal cancer-associated genes might also be associated with an increased risk of endometrial cancer. Three single-nucleotide polymorphisms were selected in the MLH1 and MSH2 mismatch repair genes. All the various 672 women with endometrial cancer and 880 controls were genotyped. Each of these three single-nucleotide polymorphisms was associated with an increased risk of endometrial cancer. Carriers of the MLH1 nt-93 A allele were at a 1.5-fold increased risk of developing endometrial cancer compared with controls [95% confidence interval (95% CI), 1.2-2.0; P = 0.001]. The risk was higher for homozygote carriers [odds ratio (OR), 1.9; 95% CI, 1.2-3.2; P = 0.009]. For carriers of the MSH2 rs2303428 C allele, the OR was 1.4 (95% CI, 1.0-1.9; P = 0.05), and for carriers of the MSH2 rs2059520 G allele, the OR was 1.3 (95% CI, 1.0-1.7; P = 0.03). More than 9% of endometrial cancer cases carried a variant allele in both MLH1 and MSH2. For these women, the risk of endometrial cancer was particularly high (OR, 2.1; 95% CI, 1.2-3.6; P = 0.005). For patients younger than 50 years at diagnosis who carried both variants, the risk was even higher (OR, 3.4; 95% CI, 1.7-6.6; P = 0.0005). In summary, two common variant alleles of the MLH1 and MSH2 genes make a substantial contribution to endometrial cancer incidence in Ontario.
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PMID:Endometrial cancer risk is associated with variants of the mismatch repair genes MLH1 and MSH2. 1698 24

Lynch syndrome (hereditary non-polyposis colorectal cancer) is characterised by the development of colorectal cancer, endometrial cancer and various other cancers, and is caused by a mutation in one of the mismatch repair genes: MLH1, MSH2, MSH6 or PMS2. The discovery of these genes, 15 years ago, has led to the identification of large numbers of affected families. In April 2006, a workshop was organised by a group of European experts in hereditary gastrointestinal cancer (the Mallorca-group), aiming to establish guidelines for the clinical management of Lynch syndrome. 21 experts from nine European countries participated in this workshop. Prior to the meeting, various participants prepared the key management issues of debate according to the latest publications. A systematic literature search using Pubmed and the Cochrane Database of Systematic Reviews reference lists of retrieved articles and manual searches of relevant articles was performed. During the workshop, all recommendations were discussed in detail. Because most of the studies that form the basis for the recommendations were descriptive and/or retrospective in nature, many of them were based on expert opinion. The guidelines described in this manuscript may be helpful for the appropriate management of families with Lynch syndrome. Prospective controlled studies should be undertaken to improve further the care of these families.
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PMID:Guidelines for the clinical management of Lynch syndrome (hereditary non-polyposis cancer). 1732 85

In 1983, Bokhman proposed a dualistic model of endometrial tumorigenesis based on the clinical observations and clinicopathologic correlations. The majority of endometrial cancers (approximately 70-80%), designated as type I carcinomas, follow the estrogen-related pathway. Histologically, most of the type I tumors seem to arise in the background of hyperplastic endometrium, show an endometrioid differentiation, and are of low grade. Clinically, they are overall characterized by a favorable behavior. Another 10-20% of endometrial cancers, designated as type II carcinomas, follow the estrogen-unrelated pathway and arise in the background of atrophic endometrium. Type II tumors usually occur at an older age, approximately 5-10 years later than type I tumors. They are typically high-grade carcinomas of nonendometrioid differentiation, most frequently serous, less frequently clear cell. Type II carcinomas behave as an aggressive clinical course and poor prognosis. This dualistic model was subsequently supported by the molecular studies, approximately a decade later. At present, endometrioid and serous carcinoma, which represent the major phenotypes of types I and II endometrial carcinomas, respectively, are characterized by distinctive types of genetic instability and molecular alterations. In endometrioid (type I) carcinoma, four major genetic changes are responsible for the tumorigenesis, i.e. silencing of PTEN tumor suppressor gene, presence of microsatellite instability due to alterations of the mismatch repair genes, mutation of K-ras protooncogene, and alteration of beta-catenin gene. On the other hand, p53 mutation and overexpression of Her2/neu oncogene are two major genetic alterations in serous and clear cell (type II) carcinomas. However, like in any model, there is evidence for exceptions. Many endometrial carcinomas are in the gray zone with overlapping clinical, morphologic, immunohistochemical, and molecular features of types I and II endometrial cancers. Finally, a small group of endometrial carcinoma is noted to be hereditary. It is known as the most common extracolonic malignancy in hereditary nonpolyposis colorectal cancer (Lynch syndrome), an autosomal dominantly inherited disorder of cancer susceptibility. Inactivation of the mismatch repair genes MSH2 and MSH6 seems to play a central role in the tumorigenesis.
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PMID:Molecular carcinogenesis of endometrial cancer. 1738 85

Identification of the microsatellite instability (MSI) phenotype in endometrial carcinoma is important given that such tumors are the most common noncolorectal tumors to occur in hereditary nonpolyposis colorectal cancer syndrome, and may bear prognostic relevance. The objective of this study was to assess the utility of immunohistochemistry (IHC), a simple and fast technique, in detecting MSI in endometrial carcinoma. The study subjects consisted of 90 endometrial carcinoma patients with equal representation of MSI-high (MSI-H) and non-MSI-H tumors. MSI was tested using the standard polymerase chain reaction-based method and the 5 NCI-recommended markers. Overall, IHC with MLH1 and MSH2 antibodies detected 69% of MSI-H tumors with a specificity of 100%. Adding PMS2 and MSH6 to the antibody panel increased the sensitivity to 91% but decreased the specificity to 83%. The most common IHC abnormality in MSI tumors was concurrent loss of MLH1/PMS2. Assessment of staining was straightforward in most cases but not in all. Staining inadequacies existed. Five stains (4 MLH1 and 1 MSH6) were not interpretable because of the lack of any internal positive control. Two percent to 10% of the cases (depending on the antibody assessed) had only focal weak staining; the highest frequency (10%) occurred with MLH1 antibody. PMS2 staining detected 7 MLH1-staining present MSI-H cases, thus partly accounting for the increased sensitivity with the 4-antibody panel. MSH6 staining identified 9 cases with loss of MSH6 alone, 6 of 9 were non-MSI-H, thus partly accounting for the decreased specificity with the 4-antibody panel. In conclusion, our results suggest that IHC is useful in detecting MSI in endometrial carcinoma. Although IHC has a lower sensitivity with more apparent staining inadequacies in detecting MSI in endometrial carcinoma than it does in colorectal carcinoma, its use in endometrial carcinoma may be an important adjunct when screening for hereditary cases. In the future, as prognostic and therapeutic implications of MSI phenotype become better defined, it may be reasonable to perform IHC for mismatch repair proteins in large numbers of endometrial carcinomas.
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PMID:Utility of immunohistochemistry in predicting microsatellite instability in endometrial carcinoma. 1746 Apr 59

The objective is to determine the relationship between obesity and defects in DNA mismatch repair (MMR) in women with endometrial cancer and to establish whether our previous finding of a higher rate of previous malignancy in thinner women with endometrial cancer is related to these factors. Specimens from 109 patients with primary uterine cancer were used to create a tissue microarray, which was stained with antibodies against MMR genes MLH1, MSH2, MSH6, and PMS2. Genotyping of normal and tumor tissues for microsatellite instability (MSI) was performed. Patients were stratified by body mass index (BMI) and correlated with a history of previous malignancy and defects in MMR. The average BMI of the overall population was 33 kg/m(2). Defective MMR was seen in 22% of tumors. The mean BMI in patients with tumors with MSI was 30.5, compared with 33.8 in microsatellite stable (MSS) tumors (P= 0.06); MSS tumors were more commonly seen in patients with a BMI more than 40 (25% vs 5% in patients with tumors with MSI, P= 0.07). Prior to their diagnosis of endometrial cancer, 16/109 (15%) patients reported having a prior malignancy, 11 (69%) had breast cancer, and 1 had colorectal cancer. Patients with tumors with MSI had previous cancer in 17% of cases, compared with 14% of patients with MSS tumors (P= 0.75). Our previous finding of an increased rate of prior malignancy in thinner patients with endometrial cancer does not appear to be due to alterations in MMR, and hereditary nonpolyposis colorectal cancer-associated cancers are rarely the prior malignancy.
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PMID:Correlation between patient weight and defects in DNA mismatch repair: is this the link between an increased risk of previous cancer in thinner women with endometrial cancer? 1746 51

Hereditary nonpolyposis colorectal cancer (HNPCC) is an autosomal dominant syndrome caused by germline mutations of the mismatch repair (MMR) genes. Only a few studies have taken into account the selection of families tested for these mutations in estimating colorectal cancer (CRC) risk in carriers. They found much lower estimates of CRC risks than previous ones, but these estimates lacked precision despite the large number of families. The aim of this study was to evaluate the efficiency of the 'genotype restricted likelihood' (GRL) method that provides unbiased estimates of risks whatever the ascertainment process of families, and to estimate CRC and endometrial cancer risk for carriers of the MMR genes. Efficiency of the GRL method was evaluated using simulations. Risks were estimated from a sample of 36 families diagnosed with HNPCC and carrying a mutation of MSH2 or MLH1, ascertained through a cancer family clinic in Lyon (France). The efficiency of the GRL method was found to be strongly dependent on the proportion of family members tested. By age 70 years, CRC risk was estimated at 47% (95% confidence interval: 12-98%) for men and 33% (95% confidence interval: 24-54%) for women. The endometrial cancer risk was only 14% (confidence interval: 6-20%). As methods allowing for the selection of families lack efficiency, large-scale family studies should be undertaken and data should be pooled to provide reliable and precise estimates of risks for an optimal familial management.
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PMID:Estimating cancer risk in HNPCC by the GRL method. 1747 34


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