| PTEN is a tumor suppressor gene with phosphatase activity. It had been proved the aberrant expression and mutation of PTEN in diverse types of humen cance; PTEN is closely is associated with occurrence and development of malignant tumor. This study was conducted to investigate the expression of PTEN protein in endometrial cyst of the ovary and ovarian endometrioid carcinoma as well as to elucidate its significance .Materials and Methods1. Materials: Paraffin - embedded tissues from 30 patients with endometrial cyst of the ovary and 30 patients with ovarian endometrioid carcinoma, and from 20 case of normal endometrium obtained from patients who received surgery at the affiliated hospital of China Medical University between 1985 - 2002 were analyzed for PTEN gene expression by imrnunohistochemical technique. Patients with ovarian endometrioid carcinoma with a mean age of 56 (range31 ~81). In ovarian endometrioid carcinoma, 3, 7, 18 and 2 of the cases were respectively classified as to FIGO stage I , II , III , IV- 16 and 14 of the cases were classified as to histological differentiation well - differentiated moderately differentiated and poorly differentiated. They had not received either chemotherapy or radiation therapy before or after surgery .2. Methods: All specimens were fixed in 4% buffered formaldehyle and pressed into routinely paraffin-embedded blocks. For each case, four-mi-crometer sections from these blocks were mounted on silane - coated slides, air-dried. Sections were dewatered and hydrated, and then treated in 3%hydrogen peroxide for 10 min to quench endoengous peroxidase. Prior to staining withthe anti - PTEN antibodies, microwave antigen - retrienval technology was used, and then non - immuno animal serum was droped to seal. All procedures were performed at room temperature and in a moist chamker, with a PBS wash after each step . PTEN antibody were droped on the slides. After over incubation at 4C , the sections were incubated with then counter - stained in Mayer' s heamatoxylin and mounted with Crystal mont.3. Statistical methods: Statistical analyses of PTEN protein expression was carried out the Chi - square method by SSPS10. 0. Differences were considered significant when P values were less than 0.05.Results1. The expression of PTEN protein in the three kind of tissue was mostly located at cell plasma, the positive cell distributed dispersively or locally. Its positive expression was found at epithelial and interstitial cells in endometrium. The positive expression of PTEN protein in ouarian endometrioid carcinoma was significantly decreased, it showed brown - yellow, decreased cell number or even without staining. The PTEN protein in normal endometrium showed high expression , but the expression of PTEN protein in endometrial cyst of ovary is between the normal endometrium and ovarian endometrioid carcinoma.2. The positive expression of PTEN protein in ovarian endometrioid carcinoma is 62. 50% in high and moderate degree differentiation, it was 14. 29% in low degree differentiation. There is significantly difference between them (P < 0.05).3. The positive expression of PTEN in ovarian endometrioid carcinoma of I or II stage was significantly higher than that of III or IV stage (P <0. 05).4. The expression of PTEN protein was not related to patient's age in ovarian endometrioid carcinoma(P > 0.05 ).Conclusion1. The expression of PTEN protein was mostly located in the cell plasma,The PTEN protein in normal endometrium showed high expression, but the expression of PTEN protein decreased or loss significantly in ovarian endometrioid carcinoma. The expression of PTEN is between the normal endometrium and o-varian endometrioid carcinoma in endometrial cyst of ovary.2. The expression of PTEN protein was significantly associated with differentiation degree of cancer cells (P < 0. 05) ,the poorer was the differentiation of ovarian endometrioid carcinoma, the weaker would be the expression of PTEN protein.3. The expression of PT...
|
PDF Full Text Request