PI3K/PKB信号激活在妊娠滋养细胞疾病发病机制中的作用

The activation of PI3K / PKB signaling in pathogenesis of gestational trophoblastic disease

目的:探讨磷脂酰肌醇3-激酶/蛋白激酶B(PI3K/PKB)信号激活对妊娠滋养细胞疾病(GTD)进展及相关干细胞转录因子FoxD3、Nanog、Stat3、Oct4和Sox2表达的影响。方法:选取20例正常胎盘、38例良性转归葡萄胎(HM-regressed)和13例恶性进展葡萄胎(HM-progressed)、6例绒癌的石蜡包埋组织,采用免疫组化检测p-PKBSer473表达。实时荧光定量PCR(RT-PCR)和Western blot法检测绒癌细胞株JEG3和JAR中FoxD3、Nanog、Stat3、Oct4和Sox2 mRNA和蛋白表达。CCK8和Transwell小室检测细胞增殖、迁移/侵袭能力。结果:p-PKBSer473表达的免疫组化评分由高到低依次为绒癌、HM-progressed、HM-regressed和正常胎盘,两两比较差异均有统计学意义(P<0.05)。PI3K抑制剂LY294002阻遏了PKB的活化,显著减弱了绒癌细胞的增殖、迁移和侵袭能力,降低了FoxD3、Nanog、Stat3的mRNA和蛋白表达,差异均有统计学意义(P<0.05)。结论:PI3K/PKB信号通道激活与GTD的进展和侵袭表型有关,可通过增强调控滋养细胞的干细胞特性而发挥作用。

Objective： To explore whether the activation of phosphoinositide-3-kinase protein kinase B（ PI3K/PKB） signaling affects the progress of gestational trophoblastic disease（ GTD） and the expressions of stem cell related transcriptional factors FoxD3,Nanog,Stat3,Oct4 and Sox2. Methods： The phosphorylated active form of PKB（ p-PKB^Ser473） was explored by immunohistochemistry in paraffin block tissues including 20 cases of normal first trimester placentas,38 cases of HM regressed,13 cases of HM progressed,and 6 cases of choriocarcinomas.The expressions of mRNAs and proteins in choriocarcinoma cell lines JEG3 and JAR were detected by quantitative RT-PCR and Western blot. The capacities of proliferation and motility choriocarcinoma cells were evaluated by CCK8 and transwell assays. Results： The expressions immunoscore of p-PKB^Ser473 in these tissues were in such order： choriocarcinoma 〉HM-progressed 〉HM-regressed 〉normal placenta,and the differences between the groups were all significant. In JEG3 and JAR cells,PI3 K inhibitor LY294002 repressed the activation of PKB,significantly attenuated the abilities of proliferation,migration and invasion,and substantially decreased the mRNA and protein expressions of FoxD3、Nanog and Stat3. Conclusion： Activated PI3 K / PKB signaling is responsible for the aggressive phenotype of GTD,which may lead to aberrant cell functions through enhancing stemness of trophoblasts.