PTEN Mutations And Protein Expression In Endometrial Carcinomas

Objactive PTEN tumor suppressor gene mutations are the most frequent genetic lesions in endometrial adenocarcinomas of the endometrioid subtype.We examined the uterine samples for PTEN 7 and 8 exons' mutations and protein expression to determine the potential role of PTEN in the process of endometrioid caicinomas.Methods three series of endometrioid carcinomas , contiguous tissues and normal endometria were studied, one for PTEN mutations in exon? and exonS by PCR-SSCP, and another for PTEN protein expression by immunohistochemistry. Results The mutation rate of PTEN 7,8 exons was 25% (13 of 53) in endometioid endometial adenocarcinoma (EEC),and EEC showed complete loss of PTEN protein expression in 66 % (35 of 53) of cases, no contiguous tissues and nomal endometria showed PTEN mutations and complete loss of PTEN protein expression. The difference of mutations and expression were statistically significant ( two-side P=0.000). 5 of contiguous tissues and 2 of nomal endometria exhibited PTEN negative glands or negative cells.The difference of mutation or complete loss in PTEN expression between less half of muscular invasion and more than half was statistically significant (P<0. 05). It seemed to be a little relationship between PTEN expression and hypertension or postmenoposal (P=0.049). There was no relationship between PTEN mutation or expression and age,diabetes mellitus,obesity, grades, cervical invasion,lymph nodes metastases,or FIGO stage. Conclusions Loss of PTEN function by mutational or other mechanisms is anevent in endometrial tumorigenesis .PTEN alteration may be contributing to cacinogenesis in the endomtrium through an estrogen-independent pathway. Ferther study for PTEN negative glands in nomal endometria may be important for early diagnosis of endometrial carcinoma.