ABSENCE OF K-RAS MUTATIONS IN THE PANCREATIC PARENCHYMA OF PATIENTS WITH CHRONIC-PANCREATITIS

BACKGROUND: Human pancreatic cancers exhibit a high frequency of K-ras mutations, METHODS: In this study we used oligonucleotide specific hy bridization to compare the frequency of K-ras mutations in genomic DNA samples prepared from 21 normal pancreatic tissues, 26 chronic pancre atitis tissues, and 24 pancreatic cancers, RESULTS: None of the DNA sa mples from normal or chronic pancreatitis tissues exhibited a K-ras mu tation at codons 12 or 13 of K-ras. In contrast, 17 of 24 DNA pancreat ic cancers harbored a K-ras mutation, Validity of the methodology was confirmed by genotyping 7 human pancreatic cancer cell lines. Analysis of focal areas of proliferation from 5 chronic pancreatitis and 5 pan creatic cancer samples processed by selective ultraviolet radiation fr actionation (SURF), a procedure used to enrich DNA isolation from foci of proliferating cells, revealed complete concordance with total geno mic DNA analysis, CONCLUSIONS: These findings indicate that the pancre atic parenchyma in patients with chronic pancreatitis most frequently does not possess a K-ras mutation, (C) 1997 by Excerpta Medica, Inc.