Mutation And Protein Expression In PTEN Gene In Endometrial Carcinoma And Their Significance

Objective To study the relationship between mutation and protein expression in tumor suppression gene PTEN and the generation and development of endometrial carcinoma. Methods Polymerase chain reation-single strand conformation polymorphism (PCR-SSCP) method and DNA sequencing technique were used to detect mutation of exon 5 and exon 8 of PTEN gene in 52 endometrial carcinoma tissues and 10 corresponding normal tissues. Immunohistochemistry was used to examine the protein expression of PTEN gene. Result 1. The mutation rate of the exon 5 and exon 8 of PTEN gene was 25%. No mutation was found in 10 normal tissues. Statistical analysis showed that histological grade, histogical type and depth of myometrial invasion had significant relationship with PTEN gene mutation(P<0. 05). 2. All normal tissues were found to express PTEN protein. PTEN protein expression deletion rate in 52 endometrial carcinoma tissues was 59.62%, significantly higher than that in the corresponding normal tissues(P<0.05). PTEN protein expression deletion was significantly associated with histological grade and type (P<0.05) , but was irrelevant to FIGO stage and depth of myometrial invasion(P>0.05). 3. Among 52 endometrial carcinoma tissues, 21 cases displayedpositive protein expression of PTEN, 31 cases displayed negative protein expression. Among 31 cases of negative expression, mutation was noted in 13 cases. Conclusion 1. Abnormal PTEN expression is associated with PTEN gene mutation, the mutation of PTEN gene is the main mechanism of the inactivation of PTEN gene. 2.Expression loss of PTEN protein and mutation of PTEN gene are well related with the generation and development of endometrial carcinomaMeasurement of PTEN gene mutation and PTEN protein expression in endometrial carcinoma might help in predicting prognosis, directing clinical treatment and providing theories for gene therapy.