Identification of three commonly deleted regions on chromosome arm 6q in human pancreatic cancer

Pancreatic cancer has one of the poorest prognoses among malignant diseases . To understand its molecular mechanisms, we studied allelic losses on the long arm of chromosome 6. Using 55 paired DNAs of tumors and their correspo nding normal tissues and 30 microsatellite markers that spanned the entire bq chromosome arm, we found three distinct regions of common allelic loss: region A, a less than 500-kb region bordered by D6S449 and D6S283 on 6q21 w ith a loss of heterozygosity (LOH) frequency of 69% (38/55); region B, a 7- cM region bordered by D6S292 and D6S308 on 6q23-q24 with a LOH frequency of 60% (33/55); and region C, a 13-cM region bordered by D6S305 and D6S264 wi th a LOH frequency of 51% (28/55). We further focused on region A and const ructed a physical map using yeast artificial chromosome (YAC) clones, their derived cosmid clones, and bacterial artificial chromosome (BAC) clones. R egion A was completely covered by three overlapping BAC clones. Our results in the present study should shed light on the cloning and characterization of tumor suppressor genes in pancreatic carcinogenesis. Genes Chromosomes Cancer 25:60-64, 1999. (C) 1999 Wiley-Liss, Inc.