SHORT COMMUNICATION Activation of K-ras in transpflantablle pancreatic duictal adeeocarcinomas of Syrian golden namsters

'To whom repnnt requests should be sent High mol. wt genomic DNA was prepared from normal hamster pancreas and the solid and ascites variants of two different hamster transplantable carcinomas, one induced by iV-nitrosobis(2-oxopropyl)amine and the other spontaneously occurring. This DNA was transfected into NIH/3T3 cells and resulted in cells that were capable of forming tumors when injected into nude mice. Analysis of the nude mouse tumors by Southern blotting revealed the presence of a band specific for hamster K-ras. Polymerase chain reaction (PCR)-mediated amplification of the K-ras codon 12—13 region of genomic DNA prepared from the transplantable tumors produced a 117 bp fragment which was analyzed by both allele-specific oligonucleotide hybridization and direct DNA sequencing. Oligonucleotide hybridization with probes specifi