Showing papers by "Michael Goggins published in 1996"

Germline BRCA2 Gene Mutations in Patients with Apparently Sporadic Pancreatic Carcinomas

Abstract: Germline mutations in BRCA2 predispose carriers to the development of breast, ovarian, and a variety of other cancers. The original localization of the BRCA2 gene was aided by its homozygous deletion in a pancreatic carcinoma; indeed, an excess of pancreatic carcinoma has been seen in some BRCA2 cancer families. To determine the involvement of BRCA2 in pancreatic carcinomas, we screened for BRCA2 alterations in an unselected panel of 41 adenocarcinomas of the pancreas (30 pancreatic adenocarcinoma xenografts and 11 pancreatic cancer cell lines). Of the 15 (27%) that had allelic loss at the BRCA2 locus, 4 (9.8%) had abnormalities in the second allele upon screening of the entire BRCA2 gene by in vitro synthesized protein assay. Three of the four mutations were considered germline in origin (7.3% overall; two were confirmed in normal tissue, and one was the 6174delT mutation from the pancreatic cancer cell line CAPAN-1, for which normal tissue was unavailable). The identification of two 6174delT mutations in this series prompted us to evaluate the prevalence of this mutation in an overlapping consecutive series of 245 patients who underwent pancreatoduodenectomy for adenocarcinoma of the pancreas. Sequence analysis of this limited region of the gene identified two additional mutations: ( a ) one additional germline 6174delT mutation (2 of 245, 0.8% overall); and ( b ) a second nearby germline 6158insT mutation. One of the patients with a germline mutation had a single relative with breast cancer, and another had a single relative with prostate cancer. None had a family history of pancreatic cancer. The incidence of germline BRCA2 mutations in apparently sporadic pancreatic cancer may be at least as high as in breast or ovarian cancer. Our results suggest that some familial risks for carcinoma will be evident only through a population-based application of gene screening techniques because a low disease penetrance of the germline mutations in some families often evades clinical suspicion.

Expression of CD44 and its variants on gastric epithelial cells of patients with Helicobacter pylori colonisation

Abstract: BACKGROUND--Studies have suggested that expression of the adhesion molecule CD44 may be of prognostic importance in gastric cancer. In addition, there is strong evidence that Helicobacter pylori has a role in gastric cancer. AIMS--To determine the expression of CD44 and its variants (v6, v9) and HLA class II molecules on human gastric epithelial cell and intraepithelial lymphocytes in patients with and without H pylori infection. PATIENTS--Eighteen patients (seven men and 11 women) attending for endoscopic evaluation because of upper gastrointestinal symptoms were included. An additional 10 patients (five men and five women) were analysed for CD44 variant expression). METHODS--Biopsy specimens were taken from the gastric antrum during endoscopy. Gastric epithelial cells and intraepithelial lymphocytes were examined by two colour flow cytometry and compared in patients with and without H pylori infection. RESULTS--Expression of CD44 and its variants (CD44 v9) was increased in epithelial cells but not in intraepithelial lymphocytes. Both epithelial cells and intraepithelial lymphocytes expressed higher levels of HLA class II molecules (DR and DP), possibly as a result of local cytokine production. Furthermore, results showed upregulation of CD44 on a gastric epithelial cell line (AGS) by cytokines and peripheral blood mononuclear cell supernatant. CONCLUSIONS--These data suggest that H pylori, either directly or through a local inflammatory response, is responsible for increased expression of CD44 and its variant CD44 v9. These data are of potential importance in relation to increased expression of CD44 and CD44 v9 on gastric carcinoma.