GKN1 Expression In Placenta Of Pre-eclampsia And Its Participation In Pathogenesis

BackgroundThe pre-eclampsia(PE)is a serious pregnancy complication to the health of mother and child,its pathogenesis is still incompletely clear.Insufficient infiltration can cause pregnancy diseases such as abortion and preeclampsia.On the contrary excessive invasion of placental trophoblasts can lead to the occurrence of diseases such as choriocarcinoma.Gastrokine 1(GKN1),also known as AMP 18(18 kDa antral mucosal protein),is a secreted protein expressed in mucosal cells on the surface of gastric antral and fundus,which suppresses tumor invasion by regulating proliferation and differentiation and induce signaling pathways to mediate apoptosis.The current study has focused on exploring the tumor suppressor properties of GKN1 and its potential clinical application in the treatment of gastrointestinal tumor diseases,with little research on the expression and function of GKN1 in other organ systems.Studies have shown that GKN1 is expressed in the placenta of normal pregnancy as well as gestational trophoblast diseases,and GKN1 located in extravillous trophoblast(EVT)of placenta.Gene array analysis in the placental tissue showed that the expression level of GKN1 in the placenta is quite high.ObjectiveTo study the expression of GKN1 mRNA and protein in the placenta of normal pregnancy and preeclampsia;Explore the effect of GKN1 on invasion、migration and proliferation of trophoblast cells through vitro cytology experiments;Rearch the biological mechanism of GKN1 and JAK-STAT signaling;Provide new ideas for the study of pathogenesis and early diagnosis as well as effective treatment of preeclampsia.Methods1.Thirty cases of normal pregnancy and preeclamptic placental tissue were collected to test GKN1 protein expression by Western blot,GKN1 mRNA expression by qRT-PCRand GKN1 expression by immunohistochemistry.2..HTR-8/Svneo cells were cultured in 1%low oxygen conditions in order to mimic preeclampsia in vitro and we verified it by qPCR and Western blot for GKN1 expression changes in HTR-8/Svneo cells.3.First of all,GKN1 was knocked down after transfection by siRNA of HTR-8/Svneo cells,then we put cells cultured in 1%low-oxygen conditions.Finally we test the proliferation ability by MTT and EDU,the invasion ability by Transwell,and the migration ability of Scratch test.4.The effect of knockdown of GKN1 on the expression changes of p-JAK2,JAK2,p-STAT3,and STAT3,in the hypoxia model of HTR-8/Svneo cells was determined by Western blot.Results1.Compared with normal pregnancy,the GKN1 mRNA and protein expression level of preeclamptic placenta tissue increased significantly,with a significant difference(P<0.01).Immunohistochemical results showed an increased expression of GKN1 in placental tissue of pre-eclampsia.2.When HTR-8/SVneo cells were cultured under hypoxiaboth the mRNA and protein expression levels of GKN1 significantly increased(P<0.01).3.GKN1 knockdown under hypoxia caused increased proliferative capacity of HTR-8/SVneo cells,both migration and invasion significantly enhanced.4.When GKN1 was knocked down in the HTR-8/Svneo cell hypoxia model,the expression levels of the p-JAK2 and p-STAT3 proteins were increased,and the JAK-STAT signaling pathway was activated.Conclusions1.GKN1 expression is increased in preeclampsia,we speculated that GKN1 may be involved in the pathogenesis of preeclampsia.2.GKN1 has inhibitory effects on the proliferation,migration and invasion of trophoblast cells,it may involved in the pathogenesis of preeclampsia by causing superficial placental implantation.3.GKN1 may participate in the pathogenesis of preeclampsia by regulating the JAK-STAT signaling pathway.