The human DNA mismatch repair genes hMSH2 and hMLH1 are responsible for the development of hereditary nonpolyposis colorectal cancer (HNPCC). Although genetic alteration of the coding region of hMSH2 and hMLH1 has been well investigated in HNPCC patients, the regulatory regions of these genes have been poorly investigated, though recent studies have defined and characterized the core promoter r...

BACKGROUND We recently showed that the mRNA levels of mismatch repair (MMR) proteins in non-small cell lung carcinoma (NSCLC) tissue specimens and the phenotypic translation of molecular MMR data refines the biology of the MMR system with consequent diagnostic implications in the clinical assessment of lung cancer patients. METHODS hMLH1 and hMSH2 mRNA expression was previously evaluated by q...

There are limited reports on methylation analysis of the premalignant lesions of gastric carcinoma thus far. This is despite the fact that gastric carcinoma is one of the tumors with a high frequency of CpG island hypermethylation. To determine the frequency and timing of hypermethylation during multistep gastric carcinogenesis, non-neoplastic gastric mucosa (n = 118), adenomas (n = 61), and ca...

BACKGROUND Elevated microsatellite alterations at selected tetranucleotide repeats (EMAST) is a genetic signature observed in 60% of sporadic colorectal cancers (CRCs). Unlike microsatellite unstable CRCs where hypermethylation of the DNA mismatch repair (MMR) gene hMLH1's promoter is causal, the precise cause of EMAST is not clearly defined but points towards hMSH3 deficiency. AIM To examine...

Alterations of the length of simple repetitive genomic sequences (microsatellite instability, MSI) characterize a distinct mechanism of colorectal carcinogenesis. Such MSI has been found to be associated with hereditary nonpolyposis colorectal cancer (HNPCC) that involves mutation of the human mismatch repair genes hMSH2 and hMLH1 as well as many sporadic cancers of most tissue types. Although ...

CONTEXT Genetic testing for cancer predisposition is evolving from purely research applications to affecting clinical management. OBJECTIVE To determine how often genetic test results for hereditary nonpolyposis colorectal cancer (HNPCC) can be definitively interpreted and used to guide clinical management. DESIGN Case-series study conducted in 1996 to 1998 in which a complete sequence anal...

INTRODUCTION Lynch syndrome or hereditary nonpolyposis colorectal cancer is caused by mutations in DNA repair genes, known as mismatch repair (MMR) genes, and is associated with microsatellite instability. Urothelial carcinoma of the renal pelvis is also associated with this syndrome. These genetic abnormalities have been described in sporadic forms of upper tract urothelial carcinoma (UTUC). ...

PURPOSE Although several gene abnormalities have been reported in endometrial carcinoma, the genetic alterations have not fully been elucidated. Recent studies have revealed frequent activating mutations of the gene for BRAF, an effector of Ras protein in the mitogen-activated protein kinase pathway, in several malignancies. However, the prevalence and significance of BRAF mutations in endometr...

In order to identify representative genetic alterations in esophageal squamous cell carcinomas (ESCC) and useful markers for future early detection, 34 ESCC samples with neighboring normal epithelia and 30 esophageal biopsy samples from Linzhou, P.R. China, were studied. Of the 38 microsatellite markers selected, half were linked with tumor suppressors. More than 40% of the tumor samples showed...

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...