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Query: UMLS:C0476089 (endometrial cancer)
 11,379 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Germline mutations in DNA mismatch repair (DNA-MMR) genes, mainly MLH1, MSH2, and MSH6, underlie Hereditary non-polyposis colorectal cancer (HNPCC) and are mostly family-specific, with few reported founder mutations in MSH2 (Ashkenazim) MLH1 (Finnish). No mutations in colon cancer susceptibility genes have ever been reported in Druze individuals, a Moslem related faith encompassing approximately 1,000,000 individuals worldwide. A novel MSH2 mutation is described in a Druze HNPCC family: a multigenerational family with 10 members in 4 generations affected with colorectal cancer (mean age of diagnosis 46.5 years), two with gastric cancer and one--endometrial cancer. Mutational analysis of the MSH2 gene using denaturing gradient gel electrophoresis (DGGE) and direct sequencing revealed the c.702delA mutation in codon 234 of exon 4 of the MSH2 gene leading to a premature early stop in codon 245, p.Thr234fsX245. Analysis of mutation-carrying or presumed carriers individuals' offspring, revealed 11/42 asymptomatic mutation carriers, age range 17-50 years. The mutation was not present in two additional Druze HNPCC families and 20 Druze sporadic colon cancer patients. This is the first mutation ever reported in a colon cancer susceptibility gene in a Druze family and it appears not to be a founder mutation in Druze individuals with HNPCC.
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PMID:A novel MSH2 germline mutation in a Druze HNPCC family. 1766 Nov 83

The family histories of 130 individuals with documented hereditary non-polyposis colorectal cancer (HNPCC) (caused by mutations in mismatch-repair (MMR) genes MSH2 (n = 64), MLH1 (n = 62) or MSH6 (n = 4)) were obtained, and incidence of cancers in those families was compared to that in the general population. There were a total of 982 cancers in 723 individuals. Colorectal cancer (CRC) was the commonest type (64% and 55% in individuals from families with germline MLH1 and MSH2 mutations respectively). Median age at diagnosis of first CRC in MSH6 mutation families was 59 years compared to 45 years in both MLH1 and MSH2 mutation families. The relative risk (RR) of endometrial cancer was 55 in MSH2 mutation families, compared with 27 in MLH1 mutation families, and 37 in MSH6 mutation families; median age at diagnosis 49 years. Even within MSH2 families, endometrial cancer tended to cluster, with 28 of the 58 cases coming from families with three or more cases (P < 0.001). Absolute risk of endometrial cancer in MLH1 families was still greater than any other cancer (other than CRC). 5% of cancers in both MLH1 and MSH2 mutation families were gastric (RR = 12); 53% of these were diagnosed before 50 years. Seven cases of small intestinal cancer occurred in MSH2 and MLH1 mutation families (RR = 26). There were 13 cases of cancer of the ureter; all were in MSH2 families. These cancers tended to cluster within families (P < 0.001); three of seven families with urothelial cancer had such cases in two or more individuals; two others had kidney cancer. Nineteen of 27 ovarian cancers (70%) were in MSH2 mutation families and 70% of these were diagnosed before age 50 years. There were 9 cases of sebaceous skin cancer, 3 in two MLH1 and 6 in four MSH2 mutation families. Of 22 pancreatic cancers, 14 were known to be diagnosed before 60 years. Breast cancer RR was 1.7 overall. The type of mutation (truncating or other type, and site of mutation) showed no obvious correlation with the presence or absence of extra-colonic cancers in families.
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PMID:Gene-related cancer spectrum in families with hereditary non-polyposis colorectal cancer (HNPCC). 1793 62

Data reduction is often desired in the development of a prediction model, for example for effects of age and family history in the identification of subjects having a genetic mutation. We aimed to evaluate a strategy for model simplification by robust coding of related predictors. We considered 898 patients suspected of having Lynch syndrome, which is caused primarily by mutations in the mismatch repair genes, MLH1 or MSH2. The presence of colorectal cancer (CRC) and endometrial cancer in patients and their relatives was related to mutation prevalence with logistic regression analysis. The performances of simplified and more complex models were quantified with a concordance statistic (c), which was corrected for optimism by cross-validation and bootstrapping. External validation was performed in 1016 patients. The first challenge was the coding of age at diagnosis of CRC, where we forced effects to be identical in patients, in 1st degree and in 2nd degree relatives, by taking the sum of the ages at diagnosis. As a further simplification, CRC diagnosis in 2nd degree relatives was weighted half that of 1st degree relatives. These data reduction approaches were also followed for endometrial cancer. The simplified model used 7 instead of 17 degrees of freedom (df) for a more complex model incorporating individual predictor effects. The optimism-corrected c was higher (0.79 instead of 0.77), but the external c was similar (0.78 for the simplified and more complex models). A stepwise selected model performed slightly worse (external c=0.77). In conclusion, a prediction model could be developed with relatively few df that captured effects of age at diagnosis across patients and relatives per type of cancer in the family. Such robust coding may especially be relevant for modeling in relatively small data sets.
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PMID:Data reduction for prediction: a case study on robust coding of age and family history for the risk of having a genetic mutation. 1794 67

Endometrial cancer is the second most common cancer in hereditary nonpolyposis colorectal cancer (HNPCC). It has often been overlooked to explore the possibility of HNPCC in endometrial cancer patients. Our study was to investigate how many HNPCC patients existed among endometrial cancer patients. Among patients who underwent hysterectomy for endometrial cancer at Seoul National University Hospital from 1996 to 2004, 113 patients were included, whose family history and clinical data could be obtained and tumor specimens were available for microsatellite instability (MSI) testing and immunohistochemical (IHC) staining of MLH1, MSH2 and MSH6 proteins. There were 4 (3.5%) clinical HNPCC patients fulfilling the Amsterdam criteria II, and 2 (2/4, 50%) of them carried MSH2 germline mutations. There were also 8 (7.1%) suspected HNPCC (s-HNPCC) patients fulfilling the revised criteria for s-HNPCC, and one (1/8, 12.5%) of them revealed MLH1 germline mutation. In 101 patients, who were not clinical HNPCC or s-HNPCC, 11 patients showed both MSI-high and loss of expression of MLH1, MSH2 or MSH6 proteins, and 2 (2/11, 18.2%) of them showed MSH6 germline mutations. In 113 patients with endometrial cancer, we could find 5 (4.4%) HNPCC patients with MMR germline mutation and 2 (1.8%) clinical HNPCC patients without identified MMR gene mutation. Family history was critical in detecting 3 HNPCC patients with MMR germline mutation, and MSI testing with IHC staining for MLH1, MSH2 and MSH6 proteins was needed in the diagnosis of 2 HNPCC patients who were not clinical HNPCC or s-HNPCC, especially for MSH6 germline mutation.
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PMID:Hereditary nonpolyposis colorectal cancer in endometrial cancer patients. 1797 65

Microsatellite instability (MSI) seems to be important for the development of various human cancers including sporadic endometrial cancer. The aim of this study was evaluation of microsatellite instability in 60 postmenopausal women with endometrial cancer in DNA samples obtained from cancer tissue and blood of the same patients. Control DNA was obtained from normal endometrial tissue (n = 70). MSI was studied at five loci containing single- or dinucleotide repeat sequences and mapping to different chromosomal locations: BAT-25 (at locus 4q12), BAT-26 (2p16), D2S123 (2p16-p21), D5S346 (5q21-q22) and D17S250 (171q11.2-q12). No differences in the MSI frequencies between blood and cancer tissue obtained from patients were detected. The microsatellite instability status was significantly higher in endometrial cancer tissue [21/60 (35%)] compared to control [8/70 (11%)] (p < 0.05). There were significant differences between MSI presence in the subgroups assigned to the histological grades (p < 0.05). The lack of association between MLH1 and MSH2 protein expression and MSI in endometrial cancer samples was observed. The results suggest that the microsatellite instability seems to be important in the development of sporadic endometrial cancer.
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PMID:Microsatellite instability (MSI) and MLH1 and MSH2 protein expression analysis in postmenopausal women with sporadic endometrial cancer. 1798 98

Lynch syndrome is the predisposition to visceral malignancies that are associated with deleterious germline mutations in DNA mismatch repair genes, including MLH1, MSH2, MSH6, and PMS2. Muir-Torre syndrome is a variant of Lynch syndrome that includes a predisposition to certain skin tumors. We determined the frequency of Muir-Torre syndrome among 50 Lynch syndrome families that were ascertained from a population-based series of cancer patients who were newly diagnosed with colorectal or endometrial carcinoma. Histories of Muir-Torre syndrome-associated skin tumors were documented during counseling of family members. Muir-Torre syndrome was observed in 14 (28%) of 50 families and in 14 (9.2%) of 152 individuals with Lynch syndrome. Four (44%) of nine families with MLH1 mutations had a member with Muir-Torre syndrome compared with 10 (42%) of 24 families with MSH2 mutations (P = .302). Families who carried the c.942+3A>T MSH2 gene mutation had a higher frequency of Muir-Torre syndrome than families who carried other mutations in the MSH2 gene (75% vs 25%; P = .026). Muir-Torre syndrome was not found in families with mutations in the MSH6 or PMS2 genes. Our results suggest that Muir-Torre syndrome is simply a variant of Lynch syndrome. Screening for Muir-Torre syndrome-associated skin lesions among patients with Lynch syndrome is recommended.
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PMID:The frequency of Muir-Torre syndrome among Lynch syndrome families. 1827 Mar 43

Ovarian malignancies occurring in the setting of hereditary nonpolyposis colorectal carcinoma syndrome typically present in young women, often as the first or "sentinel" cancer, but the frequency of microsatellite instability (MSI) and mismatch repair (MMR) defects in ovarian surface epithelial malignancies in women <or=50 years of age is neither well known nor well tested. Fifty-two ovarian surface epithelial carcinomas, including 4 with synchronous endometrial carcinomas, were identified in patients 50 years of age or younger and evaluated for evidence of MSI and MMR protein deficiency. Each case was tested for MSI by multiplex polymerase chain reaction amplification of the National Cancer Institute reference panel (BAT25, BAT26, D2S123, D5S346, and D17S250) and deficiency of MMR protein expression by immunohistochemistry (MLH1, MSH2, MSH6, and PMS2). MMR protein expression and MSI (in a subset of cases) were also evaluated in 50 unselected ovarian serous tumors of low malignant potential , a tumor common in younger women. Defects in MMR were detected in 5 of 52 (10%) ovarian carcinomas by at least 1 testing method, including 2 of 4 (50%) ovarian cancers presenting with synchronous endometrial cancer. Three of the 5 (60%) ovarian carcinomas were clear cell carcinomas (17% of all pure clear cell carcinomas) and the remaining 2 were high-grade carcinomas with endometrioid and mixed histology. Loss of MSH2 and MSH6 was detected in all of the affected clear cell carcinomas and a synchronous endometrial cancer with endometrioid histology. Loss of 1 or more MMR proteins was initially noted in 10/50 ovarian serous tumors of low malignant potential on tissue microarray, but further testing on full tissue sections showed intact protein expression and microsatellite stability in all informative cases. This study demonstrates a 10% rate of MMR-deficient ovarian cancer in women <or=50 years of age. MMR-deficient ovarian cancer is frequently associated with loss of expression of MSH2 and MSH6 proteins and clear cell histology. The occurrence of MMR inactivation in a significant proportion of ovarian clear cell carcinomas (17% in this study) suggests that this tumor may warrant targeted testing in women <or=50 years of age.
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PMID:Microsatellite instability and mismatch repair protein defects in ovarian epithelial neoplasms in patients 50 years of age and younger. 1846 6

The MLH3 gene is one of the five mismatch repair (MMR) genes associated with hereditary nonpolyposis colorectal cancer (HNPCC). Eighteen different inherited MLH3 mutations have been reported as pathogenic in an international mutation database. In several cases, a mutation was found in a patient without a family history suggestive of inherited cancer susceptibility. In some cases, a similar mutation was also found in sporadic patients and/or healthy controls. Four patients carried an MLH3 mutation together with another inherited MMR gene variation. No functional analyses have been performed to assess the pathogenicity of these 18 mutations. MLH3 has been assumed to be less important in MMR than the other HNPCC susceptibility genes MSH2, MSH6, MLH1, and PMS2, and accordingly a low-risk gene for colorectal cancer (CRC). To assess the significance of the inherited sequence variations in MLH3, we functionally characterized seven missense mutations (Q24E, R647C, S817G, G933C, W1276R, A1394T, E1451K) scattered throughout the MLH3 polypeptide. The mutations were found in CRC or endometrial cancer patients and reported as pathogenic. Our study showed that the seven mutated MLH3 proteins, in complex with their counterpart MLH1 (MutLgamma), repaired mismatches as the wild type MutLgamma but worse than a heterodimer of MLH1 and PMS2 (MutLalpha). The results confirm that MutLgamma is a less efficient MMR complex than MutLalpha and show that the MLH3 mutations alone do not interfere with MMR. Further studies are needed to evaluate the pathogenicity of MLH3 mutations in compound with other MMR mutations.
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PMID:The first functional study of MLH3 mutations found in cancer patients. 1852 50

Mono-allelic germline mutations in mismatch repair (MMR) genes lead to Lynch syndrome, an autosomal dominant syndrome with an increased risk of predominantly colorectal and endometrial cancers. Bi-allelic germline mutations in MMR genes predispose to haematological malignancies, brain tumours, gastrointestinal tumours, polyposis and features of neurofibromatosis type 1 in early childhood.We report a brother and a sister with bi-allelic germline mutations in MSH2; a pathogenic deletion of the first 6 exons and a variant of the initiation codon (c.1A>G (p.Met1?)), whereas their phenotypes (four colorectal cancers, small bowel carcinoma and 15 adenomas at age 39 and 48, and colorectal cancer, endometrial cancer and four adenomas at age 33 and 44, respectively) are more suggestive of a mono-allelic pathogenic MMR gene mutation. The carcinomas showed microsatellite instability in the presence of MLH1, PMS2, MSH2 and MSH6 proteins, indicating that the variant c.1A>G leads to an alternative protein with reduced activity that is retained in the tumours.Our data suggest that the MSH2 variant c.1A>G (p.Met1?) should not be considered as a regular pathogenic mutation that leads to a strongly increased cancer risk, though it possibly contributes to a more severe phenotype when combined with a truncating mutation on the other allele.
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PMID:Compound heterozygosity for two MSH2 mutations suggests mild consequences of the initiation codon variant c.1A>G of MSH2. 1878 Nov 92

High rates of early colorectal cancers are observed in Tunisia suggesting high genetic susceptibility. Nevertheless, up to now no molecular studies have been performed. Hereditary nonpolyposis colorectal cancer (HNPCC) is the most frequent cause of inherited colorectal cancer. It is caused by constitutional mutations in the DNA mismatch repair (MMR) genes. Here, we investigated a Tunisian family highly suspected of hereditary nonpolyposis colorectal cancer (HNPCC). Six patients were diagnosed with a colorectal or an endometrial cancer at an early age, including one young female who developed a colorectal cancer at 22 years and we tested for germline mutations in MMR genes. MMR genes were tested for rearrangements by MLPA (MLH1, MSH2) and the presence of point mutations by sequencing (MLH1, MSH2, MSH6). Moreover, tumors were analyzed for microsatellite instability and expression of MMR proteins, as well as for somatic rearrangements in MLH1 and MSH2 by MLPA. MMR gene analysis by MLPA revealed the presence of a large deletion in MLH1 removing exon 6. Sequence analysis of the breakpoint region showed that this rearrangement resulted from a homologous unequal recombination mediated by a repetitive Alu sequence. Moreover, tumors harbored biallelic deletion of MLH1 exon 6 and loss of heterozygosity at MLH1 intragenic markers, suggesting duplication of the rearranged allele in the tumor. This germline MLH1 rearrangement was associated to a severe phenotype in this family. This is the first report of a molecular analysis in a Tunisian family with HNPCC.
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PMID:Identification and characterization of a novel MLH1 genomic rearrangement as the cause of HNPCC in a Tunisian family: evidence for a homologous Alu-mediated recombination. 1879 5


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