摘要
Breast and ovarian cancers exhibit several similar epidemiologic, genotypic and phenotypic characteristics suggesting that similar underlying genetic defects may contribute to the development of both tumor types. Phosphatidylinositol 3 kinase (PI3K) and the PTEN tumor suppressor gene product phosphorylate and dephosphorylate the same 3' site in the inositol ring of membrane phosphatidylinositols. Germline mutations in the PTEN tumor suppressor gene are causative of the Cowden's breast cancer predisposition syndrome and PTEN is frequently mutated or expressed at decreased levels in sporadic breast cancers. PTEN is also frequently mutated in gliomas, prostate cancer, endometrioid ovarian cancer and
