Changes of tumor suppressor gene PTEN and microsatellite instability in the malignant transformation of endometriosis and their correlations.

Objective:To investigate the mutation of PTEN and microsatellite instability in the malignant transformation of endometriosis. Methods: 26 cases of endometriosis associated ovarian cancers (EAOC), 7 cases of atypical hyperplasia endometriosis of ovary and 25 cases of typical endometriosis tissues were collected from Qingdao University affiliated Hospital and Qingdao Municipal Hospital. PCR-SSCP silver staining was used to analyze microsatellite instability. PTEN mutations were detected by PCR-SSCP and ABI sequencing. Result: The percentages of PTEN mutation in EAOC, aEMs and EMT were 30.76%,14.29% and 8% separately, meanwhile, the incidence rate of MSI were 46.15%,28.67% and 0%. In EAOC cases, the mutation rate of PTEN and the incidence of MSI are significantly higher than those in aEMS cases and those in EMT cases, and interestingly, PTEN-mutaion rate could be proportionate to MSI incidence. Conclusion: Mutation of PTEN gene and Microsatellite Instability are highly associated with the malignant transformation of endometriosis.