Saikosaponins-b suppresses tumor growth and angiogenesis of hepatocellular carcinoma by regulating VEGF/ERK/HIF-1α signal pathway

摘要

OBJECTIVE Angiogenesis therapy has attracted interest as a potential treatment for hepatocellular carcinoma (HCC). In this study, we investigated the anti-proliferative activities and anti-angiogenesis effects of saikosaponins (SS)-b on hepatocellular carcinoma (HCC) and its regulation on VEGF/ERK/HIF-1α signal pathway. METHODS H22 hepatoma-bearing mice model and HepG-2 cells were used to study the anti-tumor and anti-angiogenesis effects of SS-b in vivo and in vitro. Pathological change of tumor tissue was observed by HE staining, the microvascular changes were detected by immunohistochemical method. The effects of SS-b on angiogenesis were examined by using the chick embryo chorioallantoic membrane (CAM) model. The effects of SS- b on proliferation, migration and invasion were investigated by MTT assay, scratch wound healing assay and transwell assay inhuman umbilical vein endothelial cell (HUVEC) and HepG2 cells in vitro. Vascular endothelial growth factor (VEGF), matrix metalloproteinase-2/9(MMP-2/9), hypoxia-inducible factor-1α (HIF-1α) expression and the phosphorylation of extracellular regulated kinase(ERK) were analyzed using RT-PCR and Western-blot. RESULTS SS-b effectively inhibited the tumor growth of H22 mice in vivo. The inhibitory rate of tumor was 49.1%, 50.7%, 66.1% in SS-b 5, 10 and 20 mg·kg-1 group respectively. HE staining results showed that SS-b induced tumor necrosis and nuclear dissolution in H22 mice. Moreover, SS-b also reduced the number of microvessels of tumor tissue in H22 mice significantly and suppressed the angiogenesis of CAM induced by b-FGF. SS-b had an obvious inhibitory effect on cell proliferation, migration and invasion of HUVEC cells and HepG-2 cells. These effects were associated with down-regulation of the expression of MMP2/9 and suppression of VEGF/ERK/HIF-1α signaling in H22 mice and Hep-G2 cells. CONCLUSION Our findings showed that SS-b exerts anti-tumor effects by inhibit?ing tumor angiogenesis via regulating VEGF/ERK/HIF-1α signal pathway in vivo and in vitro.