IL-8 And Low Shear Stress Induces Epithelial-to-mesenchymal Transition Of Ovarian-cell Carcinoma And Its Molecular Mechanism:A Preliminary Study

Objective: To observe the effect of low shear stress and IL-8 on the epithelial-to-mesenchymal transition(EMT)in ovarian cancer and analyze the role of Wnt/?-catenin signal pathway in this process as well as reveal the molecular mechanism and provide molecular targeted drugs and experimental basis for the early diagnosis,prevention and intervention of ovarian cancer.Methods: 1.Immunohitochemistry was used to detect the expression of IL-8 and IL-8 receptors CXCR1,CXCR2 in 91 serous ovarian cancers and the expression of IL-8,CXCR1,CXCR2 in SKOV3 cell line.2.SKOV3 cell lines was co-cultured with exogenous people restructuring IL-8 for 48 h,proteins involved in Wnt/?-catenin pathway and EMT were investigated via western blot to explore the effect of IL-8 on the activation of the Wnt/?-catenin pathway and EMT.3.Invasion,migration and the cytoskeleton rearrangement of SKOV3 cell lines and the normal ovarian epithelial cell line HOSEpiC after treatment with IL-8 were evaluated by immunofluorescence,transwell assay and RTCA,the expression of cilia kinesin(KIF3A)was detected by Western blot.4.Shear stresses of 1.5 dyne/cm2 were applied on the surface of SKOV3 cell lines for 2 h to evaluate the effect of low shear stress on the activation of the Wnt/?-catenin pathway and EMT.Results: 1.Among 91 cases of serous ovarian cancer,82 cases(90.1%)expressed IL-8,89 cases(97.8%)expressed CXCR1,88 cases(96.7%)expressed CXCR2.In the SKOV3 cell line,IL-8?CXCR1?CXCR2 were expressed.IL-8 expression in ovarian cancer show significantly positive correlation(r = 0.253,P < 0.05)with CXCR2,but no correlation with CXCR1(r = 0.178,P > 0.178).2.After treatment with IL-8(100 ng/mL)for 48 h,the elevated expression of P-?-catenin,?-catenin,MET,c-Jun and CD44 in IL-8 pretreated cells showed the activation of Wnt/?-catenin pathway.Also,the upregulation of vimentin and snail,the downregulation of E-cadherin suggested that IL-8 induced EMT in ovarian cancer.3.IL-8(100 ng/mL)can induce the expression of KIF3 A in SKOV3 to rearrange the cytoskeleton of ovarian cancer cell and promote the formation of cilia pseudopodia.4.According to the results of transwell test and RTCA,invasive ability of IL-8(100 ng/m L)pretreated ovarian cancer cells(SKOV3)were enhanced(P < 0.05),while normal ovarian epithelial cell line(HOSEpiC)showed no statistically significant difference after the stimulation.5.Compared with the control group,critical proteins in Wnt/?-catenin pathway including P-?-catenin and ?-catenin were upregulated after the application of the 1.5 dyne/cm2 shear stress for 2 h.Additionally,EMT-associated proteins including vimentin was upregulated,E-cadherin was downregulated,which suggested the EMT of ovarian cancer.Conclusions: In our study,low shear stress and IL-8 can induce the EMT of ovarian cancer via the activation of Wnt/?-catenin pathway and enhance the invasion and migration of ovarian cancer by the rearrangement the cytoskeleton of ovarian cancer cell as well as the formation of cilia pseudopodia.Therefore,key physical and chemical factors in the tumor microenvironment(low shear stress or IL-8)may play a critical role in the progress of ovarian cancer and the associated molecular pathway may be the pathological basis of early malignant transformation of ovarian cancer cells.In future,further study for this process can provide new targets for the prevention and treatment of ovarian cancer and for the screening of targeted drugs.