Gene Expression Patterns in Ovarian Carcinomas
Abstract
We used DNA microarrays to characterize the global gene expression patterns in surface epithelial cancers of the ovary. We identified groups of genes that distinguished the clear cell subtype from other ovarian carcinomas, grade I and II from grade III serous papillary carcinomas, and ovarian from breast carcinomas. Six clear cell carcinomas were distinguished from 36 other ovarian carcinomas (predominantly serous papillary) based on their gene expression patterns. The differences may yield insights into the worse prognosis and therapeutic resistance associated with clear cell carcinomas. A comparison of the gene expression patterns in the ovarian cancers to published data of gene expression in breast cancers revealed a large number of differentially expressed genes. We identified a group of 62 genes that correctly classified all 125 breast and ovarian cancer specimens. Among the best discriminators more highly expressed in the ovarian carcinomas were PAX8 (paired box gene 8), mesothelin, and ephrin-B1 (EFNB1). Although estrogen receptor was expressed in both the ovarian and breast cancers, genes that are coregulated with the estrogen receptor in breast cancers, including GATA-3, LIV-1, and X-box binding protein 1, did not show a similar pattern of coexpression in the ovarian cancers.
Acknowledgments
This work was supported by National Institutes of Health Grants R33 CA 89830 (B.I.S.), U01 CA 85129 (P.O.B. and D.B.), and T32 CA09302 (Cancer Biology Training Grant, M.E.S.), California Cancer Research Program Grant 99–00561V-10091 (B.I.S.), the Howard Hughes Medical Institute, and the Margaret Fagin and Beatrice Quackenbush Research Funds for Ovarian Cancer.