EXPRESSION OF CYCLIN D1 AND C-KI-RAS GENE-PRODUCT IN HUMAN EPITHELIALOVARIAN-TUMORS

The expression of cyclin D1 gene product in human ovarian tumors was s tudied. We found that cyclin D1 is expressed at high levels in several ovarian cancer cell lines. Immunohistochemical study also showed that a significant proportion of primary ovarian tumor tissues overexpress ed cyclin D1 gene product. Clear nuclear staining of cl clin D1 protei n was detected in 28% of the cases. We also characterized the expressi on of c-Ki-ras gene product in ovarian cancer cell lines and tumor tis sues. Amplification or overexpression of this protooncogene has been r eported in ovarian tumors from Taiwan. These results show that c-Ki-ra s is strongly expressed in PA-1 and NIH:OVCAR-3 cells in which cyclin D1 also expressed at high levels. Specific cytoplasmic staining of c-K i-ras protein was detected in 11 tumors (52%). Statistical analyses sh ow a strong positive correlation between cyclin D1 and c-Ki-ras immuno expression. Thus, these data support the ideas that cyclin D1 may be i nvolved in the pathogenesis of ovarian cancer, and coactivation of cyc lin D1 and c-Ki-ras gene expression may represent one of the major pat hways that lead to the development of ovarian cancer in Taiwan. Copyri ght (C) 1996 by W.B. Saunders Company