Some previous studies have reported an improved prognosis in sporadic colon cancers with microsatellite instability, whereas others have not. In addition, relatively few of those reporting an improved prognosis controlled for tumor stage or were population-based. Therefore, we evaluated the relationship between microsatellite instability and prognosis, tumor stage, and other clinical variables ...

Many lines of evidence suggest that the retinoblastoma protein interacting zinc finger gene RIZ is a strong candidate for the tumor suppressor locus on 1p36, a region commonly deleted in many human cancers with chromosomal instability. In addition, a role for RIZ in tumors of the microsatellite instability pathway is suggested by frequent frameshift mutations in hereditary non-polyposis colorec...

We investigated a possible role of hMLH1 hypermethylation and microsatellite instability in meningioma progression. Fifty meningomas were examined for methylation of hMLH1 using a methylation-specific PCR; 43 of them were analyzed for microsatellite instability using nine microsatellite markers. Loss of heterozygosity on chromosome 22q was detected using two markers. Two atypical meningio...

Almost 20% of colon cancers are characterized by genomic instability at simple repeated sequences. This instability is the result of a deficient DNA mismatch repair system. Sporadic, as well as hereditary carcinomas of the proximal colon display this effect. In this study, we examined colorectal adenocarcinoma cell lines, with or without wild-type adenomatous polyposis coli (APC) protein, for t...

We hypothesized that in a comprehensive analysis of colorectal carcinomas (CRC) the three currently known major molecular mechanisms of carcinogenesis (i.e., chromosomal instability, microsatellite instability, and CpG island methylator phenotype, CIMP) would associate with the molecular features indicative of these pathways, allowing a molecular classification. A prospectively collected clinic...

The DNA repair protein O6-methylguanine-DNA methyltransferase (MGMT) is involved in cellular defences against alkylating agents. Alterations in the MGMT gene may result in an increase in the mutation rate and risk of malignant transformation. We have previously shown that MGMT is implicated in colorectal carcinogenesis particularly in cancers which display microsatellite instability, a marker o...

The aim of the present study was to confirm the frequency of microsatellite instability in thyroid cancers. We investigated 26 patients suffering from thyroid cancer (25 papillary carcinomas, 1 follicular carcinoma) using 8 microsatellite markers. Microsatellite instability (MSI) was found in two (7.7%) papillary carcinomas. Our data indicate that MSI is a relatively rare event and may seldom c...

The serrated pathway has recently been proposed as a route for the development of colorectal cancer with microsatellite instability. Hyperplastic polyposis syndrome is a rare syndrome defined by the presence of numerous serrated polyps, with a high risk of developing into colorectal cancer. We present here a case of hyperplastic polyposis syndrome developing into colorectal cancer with microsat...

AIM To investigate the presence of genetic instability in precancerous lesions of the stomach. METHODS Fifteen cases of sporadic gastric cancers with a background of intestinal metaplasia were studied by microsatellite assay at nine loci. Altered metaplastic mucosa was microdissected, reconstructed topographically, and examined immunohistochemically with an anti-p53 antibody, comparing its po...

PURPOSE The epidermal growth factor receptor (EGFR) is overexpressed in several tumor types, and its expression is influenced by the length of a 5'-end microsatellite repeat (CA)n: the longer the repeat, the lower the expression. Dinucleotide repeats accumulate insertion/deletion types of mutations in tumors with microsatellite instability. We designed this study to estimate the occurrence of t...