Absence of Mitochondrial DNA Displacement Loop Mutations in Hamster Pancreatic Duct Adenocarcinomas and Established Cell Lines

Abstract

Mutations in the mitochondrial DNA (mtDNA) displacement loop (D-loop) region were investigated to clarify the possible molecular mechanisms underlying the development of hamster pancreatic tumors. Female Syrian golden hamsters received 30 mg/kg N-nitrosobis(2-oxopropyl)amine (BOP), followed by repeated exposure to an augmentation pressure regimen consisting of a choline-deficient diet combined with ethionine, then methionine injections and a further administration of 20 mg/kg BOP. A total of 11 pancreatic duct adenocarcinomas (PDAs) were obtained 10 weeks after beginning the experiment, and three cell lines established from subcutaneously transplantable PDAs in syngeneic hamsters were examined for mutations using polymerase chain reaction (PCR) - single strand conformation polymorphism (SSCP) analysis. No mutations were detected in the 11 PDAs and 3 cell lines. These results suggest that alterations of the mtDNA D-loop might not be involved in BOP-induced pancreatic duct carcinogenesis in hamsters.