Frequent K-ras mutations and absence of p53 mutations in mucin-producing tumors of the pancreas.
Mucin-producing tumors of the pancreas (MPT) are characterized by the production of much mucin and a benign course after surgical treatment. We examined 16 cases of MPT and 20 cases of "common" pancreatic duct cell carcinomas (DCC) in regard to K-ras and p53 mutations. The mutations were detected by constant denaturant gel electrophoresis in combination with other techniques using PCR products amplified from the samples microdissected from the tissue sections. K-ras codon 12 mutations were identified in all MPT and in 95% of DCC. On the other hand, p53 mutations were found in four of 20 (20%) DCC, and p53 was immunocytochemically overexpressed in 3 of the 4 mutated cases. However, no p53 mutations and no p53 overexpression were identified in the 16 MPT. These results indicate that, although the K-ras codon 12 mutations may be almost essential for the development of both MPT and DCC, p53 mutations seemed to be involved mainly to the latters.
Hoshi
T
T
Department of Pathology, Asahikawa Medical College, Japan.
Imai
M
M
Ogawa
K
K
D002288:Adenocarcinoma, Mucinous / Q000235:genetics*; D000236:Adenoma / Q000235:genetics*; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001483:Base Sequence; D002285:Carcinoma, Intraductal, Noninfiltrating / Q000235:genetics; D005260:Female; D016158:Genes, p53 / Q000235:genetics*; D011905:Genes, ras / Q000235:genetics*; D006801:Humans; D008297:Male; D008875:Middle Aged; D008969:Molecular Sequence Data; D009077:Mucins / Q000096:biosynthesis*; D009154:Mutation; D010190:Pancreatic Neoplasms / Q000235:genetics*; D016133:Polymerase Chain Reaction
D009077:Mucins