Mutation of the PTEN tumor suppressor gene is not a feature of ovarian cancers

Objective. The PTEN tumor suppressor gene on chromosome 10q23 undergoes inactivating mutations in several types of malignancies including glioblastomas and prostate and endometrial carcinomas. The aim of this study was to determine if mutation of the PTEN tumor suppressor gene is a feature of sporadic or BRCA1-associated ovarian carcinomas. Methods. Genomic deoxyribonucleic acid was extracted from 11 ovarian cancer cell lines and 50 frozen ovarian cancers, including 4 cases that developed in women with germline mutations in the BRCA1 breast/ovarian cancer susceptibility gene. The polymerase chain reaction was used to amplify each of the nine exons and intronic splice sites of the PTEN gene. These products were then screened for mutations using single strand conformation polymorphism analysis. Variant bands were further evaluated using automated DNA sequencing. Results. A previously unreported silent polymorphism at codon 240 (TAT to TAG) in exon 7 was noted in one of the primary ovarian carcinomas. Mutations in the PTEN gene were not found in any of the 50 primary ovarian cancers or 11 immortalized ovarian cancer cell lines. Conclusion. Alteration of the PTEN tumor suppressor gene does not appear to be a feature of sporadic or BRCA1-associated ovarian cancers. (C) 1998 Academic Press.