Defects in the function of mismatch repair (MMR) genes result in genetic instability, a common feature of malignant progression. This study was conducted to determine the frequency of genetic instability [defined as microsatellite instability (MSI)] and to evaluate the sensitivity/specificity of immunohistochemistry in predicting the deficiency in MMR genes in renal cortical tumors. A total of ...

UNLABELLED Correction of misincorporated nucleotides during DNA replication (mismatch repair) distinguishes histologically similar cancers with distinct biological and clinical behavior. We investigated expression of two mismatch repair genes in testis cancer to determine the expression pattern in histologically distinct subtypes, correlate expression with genetic instability and correlate expr...

BACKGROUND Clinical diagnosis of hereditary non-polyposis colorectal cancer (HNPCC) is based on a typical family history. As molecular genetic testing is predominantly restricted to these families, gene carriers not meeting the clinical criteria may be missed. AIMS To examine the value of microsatellite instability (MSI) as a tool to increase the likelihood for uncovering a mismatch repair ge...

BACKGROUND Gastric dysplasia (GD) is a precursor lesion of gastric adenocarcinoma. Intestinal type gastric carcinoma commonly shows microsatellite instability (MSI) and the diffuse type is associated with down regulation of E-cadherin. HER-2/neu is over-expressed in some cases of gastric cancer. In this study, MSI and expression rates of HER-2/neu and E-cadherin in GD were evaluated. METHODS Pa...

BACKGROUND Colorectal (CRC) carcinogenesis through various morphological stages has been linked to several genetic and epigenetic changes. The Raf/MEK/ERK (MAPK) signal transduction cascade is an important mediator of a number of cellular fates. METHODS In this study, we investigated the presence of B-raf and K-ras mutations in 94 consecutive cases of primary colon adenocarcinoma in correlati...

The mechanism of DNA mismatch repair has been modeled upon biochemical studies of the E. coli DNA adenine methylation-instructed pathway where the initial recognition of mismatched nucleotides is performed by the MutS protein. MutS homologs (MSH) have been identified based on a highly conserved region containing a Walker-A adenine nucleotide binding motif. Here we show that adenine nucleotide b...

Germline mutations of the hit SI 12 gene are responsible for many cases of hereditary nonpolyposis colorectal cancer. While screening for HMSH2 gene mutations in hereditary nonpolyposis colorectal cancer kindreds, we observed that a previously reported germline mutation is in fact a com mon, alternatively spliced variant in the population. Using RT-PCR and the protein truncation test, the hMSH2...

Conversion of diploidy to haploidy is a method that allows the generation of stable murine/human hybrid cell lines carrying selected human chromosomes in only a single copy. In this setting, it is possible to detect genetic mutations with greater sensitivity and reliability than in diploid cells. Using this method, we were able to identify mutations in the human mismatch repair (MMR) gene hMSH2...

BACKGROUND Ovarian clear-cell carcinoma (OCC) is known to have a poor prognosis and selected genetic features of OCC remain unknown. We investigated microsatellite instability (MSI) and the expression of the DNA mismatch repair-related protein, p53. MATERIALS AND METHODS MSI was examined by polymerase chain reaction using mono-, di-, tri- and tetranucleotide repeat markers, and hMSH2, hMLH1, ...