ANALYSIS AND CLINICAL IMPLICATIONS OF K-RAS GENE-MUTATIONS AND INFECTION WITH HUMAN PAPILLOMAVIRUS TYPE-16 AND TYPE-18 IN PRIMARY ADENOCARCINOMA OF THE UTERINE CERVIX

Experimental models indicate that activated ras genes and HPV oncogeni c sequences may cooperate in inducing a completely transformed phenoty pe in epithelial cells. We searched for K-ras gene mutations and HPV t ype-16 and -18 sequences in 67 primary adenocarcinomas of the uterine cervix by analyzing DNAs from formalin-fixed, paraffin-embedded tissue samples. Target sequences were amplified by PCR and analyzed by denat uring gradient gel electrophoresis (DGGE) and sequencing for the detec tion of K-ras gene mutations and by Southern blotting for the detectio n of HPV infection. We found 16 mutations in 15 cases; 14 were at codo n 12 and 2 at codon 13;11 were base transitions and 5 were transversio ns. Mutations were more frequent in mucin-secreting than in non-mucino us tumors. HPV oncogenic sequences were detected in 58 cases with no s ignificant difference between K-ras-mutated and wild-type tumors. HPV oncogenic sequences were also more frequent in mucin-secreting than in non-mucinous tumors. Both molecular events were present simultaneousl y in 13 out of 58 cases, all of which had histologically grade-2 and g rade-3 tumors. Clinicopathological parameters of the disease and the o verall survival, however, were independent of K-ras mutations and of H PV-16 and -18 infection, as shown by univariate and multivariate analy sis. In contrast, stage of disease, lymph-node metastases, deep infilt ration, clear-cell histology and low grade of differentiation were ris k factors for tumor-related death. (C) 1995 Wiley-Liss, Inc.