Study Of The Homozygous Deletion And Protein Expression Of P16,P15,PTEN Genes In Gestational Trophoblastic Disease

Objective To study the relationship between the homozygous deletion and protein expression of P16,P15, PTEN and the genesis and development of gestational trophoblastic disease. Methods Polymerase chain reaction (PCR) and immunohistochemical PV9000 method were performed to search for homozygous deletion and protein expression of the three genes in the tissues of 63 cases of trophoblastic disease (hydatidiform mole 40 cases, invasive moles 11 cases and choriocarcinoma 12 cases) and 25 cases of normal chorion of early gestation. Results No deletion were detected and the expression of p16, p15 and PTEN were all positive in the chorion of early gestation. The homozygous delation of P16 gene in hydatidiform mole, invasive mole and choriocarcinoma were respectively 35%, 27. 3%, 33. 3%, and P16 protein expression deletion rate were 42.5%, 36. 4%, 41.7%. All were significantly higher than that in the chorion of early gestation (p<0. 05), but were the same between each other (p>. 05). The Homozygous delation of P15 gene in hydatidiform mole, invasive mole and choriocarcinoma were respectively 27. 5%, 27. 3%, 25%, and P15 protein expression deletion rate were 30%, 27.3%, 33. 3%. All were significantly higher than that in the chorion of early gestation (p<0. 05), but were the same to each other (p>. 05). P16 and P15 co-negative was observed in 42.9% (homozygous deletion), 57. l%(protein expression) hydatidtform mole cases which had become choricocarcinorma and 18. 2% (homozygous deletion),18. 2%(protein expression) in other hydatidiform mole cases, which had no diffierence between them in statistics, but if they were followed by enlarged uterus, theca lutein cysts more than 6cm, as wellas more than two-monthly abnormal P-HCG values after suction curettage, there were difficulties between them. P16 and P15 gene co-negative was observed in 13.3% stage I -II of trophoblastic tumor, and 37.5% stage III -IV.There were no diffierence between them in statistics (P>0.05).P16 and P15 protein co-negative was observed in 13.3% stage I-II of trophoblastic tumor, and 62.5% Stage III-IV. There was diffierence between them in statistics. 80% co-negative expression of P16 and P15 gene and protein in obituary cases of choricocarcinorma, and 11. l%(homozygous deletion), 16. 7%(protein expression)in other cases,which was different in statistics (P<0. 05). P16 and P15 gene and protein co-negative was observed in 42.9% choricocarcinorma from normal gestation and 0%(homozygous deletion).. 20%(protein expression)from hydatidiform mole,but there was no difference in statistics. The Homzoygous delation and protein expression deletion rate of Pten in hydatidiform mole, invasive mole and choriocarcinoma were all 0%, and the same to the chorion of early gestation(p>0. 05). Conclusion The homuzygous deletion and expressin loss of P16 and P15 are well related with the generation and development of hydatidiform mole, invasive mole and choriocarcinoma. Measurement of P16-. P15 gene deletion and protein expression in hydatidiform mole, invasive mole and choriocarcinoma might help in dignosing , directing clinical treatment and providing theories for gene therapy. Abnormal P16 expression is associated with P16 gene deletion, and abnormal P15 expression is associated with P15 gene deletion in hydatidiform mole, invasive mole and choriocarcinoma. P16 and P15 may be useful predictive indicators for carcinomatous change and could guide clinical treatment.The homozygous deletion of P16 and P15 genes play an important role in the genesis and development of trophoblastic neoplasm, and in related to the grading, FIGOstage and prognosis. Hydatidiform mole, invasive mole and choriocarcinoma may be irrelevant to PTEN.