Inhibiting CtBP2 Expression Blocks Development Of Esophageal Squamous Cell Carcinoma Through Decreasing Angiogenesis

Objective To investigate the effects of CtBP2 on angiogenesis of human esophageal squamous cell carcinoma(ESCC),and to explain the mechanism of it.Methods(1)We first evaluated CtBP2 protein expression of ESCC tumor and adjacent normal tissues by immunohistochemistry(IHC)and Western blot(WB)assay.Meanwhile,the number of vessels of ESCC and adjacent normal tissues were measured by immunofluorescence.(2)In cell experiments,cells were divided into five groups by cell transfection technique: cells transfected with Flag-Ct BP2 plasmid,cells transfected with CtBP2 siRNA plasmid,cells transfected with Flag-Empty plasmid,cells transfected with Empty-siRNA plasmid and un transfected ECA 199 cells.The five cell groups were co-cultured with endothelial cells respectively.(3)CtBP2 and CD31 protein expression of the five co-cultured cell groups were measured by Western blot assay.Meanwhile,the effct of CtBP2 protein expression level on angiogenesis was detected by EPC tube formation.(4)The effects of CtBP2 on proliferation,apoptosis and migration abilities of endothelial cells were evaluated by EdU incorporation assay,flow cytometry detection,and wound healing assay.(5)The effects of CtBP2 on the release of angigenetic factors of endothelial cells were evaluated by qRT-PCR and WB.(6)The relationship between CtBP2 and Tel was detected by co-immunoprecipitation and co-localization of them was detected by immunoflurescence.Conclusion(1)Expression of CtBP2 and the number of microvessels increased in ECSS.(2)Blocking CtBP2 expression inhibits vascular endothelial cell angiogenesis.(3)Blocking CtBP2 expression decreases proliferation and migration in vascular endothelial cells while increasing apoptosis.(4)Reduced Ct BP2 expression in ECA109 decreases the release of angiogenetic factors.(5)CtBP2 activates angiogenesis of ECSS by CtBP2-Tel complex.Results(1)Blocking CtBP2 expression decreases proliferation and migration while increasing apoptosis in vascular endothelial,and decreases the release of angiogenetic factors.(2)CtBP2 may activate angiogenesis by Ct BP2-Tel complex.