The Expression Of E-cadherin In Placenta And Its Significance In Pre-eclampsia

ObjectiveTo investigate the expression of E-cadherin(E-cad) in placenta both of normal pregnancies and pregnancies complicated by pre-eclampsia, and the influence of hypoxia on the expression level of E-cadherin(E-cad) in trophoblast, so as to elucidating the significance of the expression of E-cad in preeclampsia.MethodsWe collected placenta tissues from Tongji hospital, and separated them into two groups: normal pregnancies (14 specimens) and pregnancies complicated by preeclampsia (10 specimens). Immunohistochemistry was used to investigate the distribution and location of E-cad in these specimens. And highly precise corlor-image measure system was taken advantage for quantitative analysis.The trophoblast cells were cultured and separated into two groups, one group cultured in normoxia environment, the other one in hypoxia environment. The expression of E-cad in the two groups was tested by immunohistochemical assay at the protein level and RT-PCR at the mRNA level.Result1.There was no difference in the distribution of E-cad in placenta of two groups. It was localized in cytotrophoblast. Few expressions were found in syncytiotrophoblast or endothelial cells.2.The rate of positive expression of E-cad was significantly higher in placenta of pregnancies complicated by preeclampsia than normal pregnacies.3.The expression of E-cad in trophoblast cultured in hypoxia was significantly higher than that cultured in normoxia, both at the protein level and the mRNA level.Conclusion1.E-cad specific expressed in cytotrophoblast. And the abnormal high expression of the protein in placenta has relationship with the pathogenesis of preeclampsia;2.Long-term hypoxia may induce trophoblast abnormal high expression of E-cad, which reduced trophoblastic erosion, causing shallow placental implantation.