MYPT1 Suppresses The Angiogenesis Of Prostate Cancer Via Regulating VEGF Expression

Purpose:Tumor angiogenesis is closely related to the growth of tumors.Previous studies have found that MYPT1 may inhibit tumor growth in prostate cancer cells.This time we aimed to investigate the role of myosin phosphatase myosin binding subunit 1(MYPT1)in prostate cancer and its effect on tumor angiogenesis.Methods:1.Western blot was carried out to detect the protein levels of VEGFA in the DU145 and LNCa P cell lines overexpressing and or downregulating MYPT1.2.Immunohistochemistry(IHC)analysis was performed to evaluate the CD31 expression pattern in tissue from xenograft tumors established by DU145 and LNCa P cell lines overexpressing or downregulating MYPT1.Western blot was also carried out to detect the protein levels of VEGFA in tissue from those xenograft tumors.3.Tube formation test of HUVECs with the culture medium of si-MYPT1-transfected and pre-MYPT1-transfected LNCa P and DU145 cells.Results:1.Western blot analysis showed that the expression levels of MYPT1 in PCa cells(LNCa P and DU145)transfected with si-MYPT1 and MYPT1 expression vector were respectively lower and higher than those with si-NC and control expression vectors(all P<0.01.).2.The immunostaining of CD31 protein in the tumor xenografts established by si-MYPT1-transfected LNCa P or DU145 cells were markedly stronger than that in the control groups(both P<0.01).The expression levels of VEGF protein in tumor tissues of the subcutaneous models bearing si-MYPT1 and MYPT1-expression-vector-transfected PCa cells were significantly increased and decreased in the comparison with the respective controls(both P<0.01).3.Tube formation test of si-MYPT1-transfected LNCa P and DU145 cells significantly promoted the capillary tube formation,while the medium of MYPT1-transfected LNCa P and DU145 cells obviously enhanced the abilities of capillary tube formation.Conclusions:Our findings indicate that MYPT1 suppresses the angiogenesis of prostate cancer via regulating VEGF expression,implying that MYPT1 might be a potential drug candidate in anticancer therapy.