Sanshimao formula inhibits the hypoxia-induced pro-angiogenesis of hepatocellular carcinoma cells partly through regulating MKK6/p38 signaling pathway

Abstract

Objectives: Sanshimao (SSM) is a traditional Chinese medicine formula for advanced hepatocellular carcinoma (HCC). This study was designed to investigate the effect of SSM on HCC-induced angiogenesis and to explore the potential mechanism.

Methods: The endothelial cells were cultured with HCC cells conditioned medium in the 1% oxygen atmosphere to imitate tumor hypoxia microenvironment. EA.hy926 cells migration and tubulogenesis were detected by tube formation and scratch-wound assay. The protein microarray was employed to explore SSM-targeted proteins in Huh7 cells. We also established an animal model to observe the effects of SSM on angiogenesis in vivo.

Results: The data indicated that SSM reduced HCC-induced migration and tube formation of EA.hy926 cells at low dose under hypoxic conditions. These effects might be partly owing to suppression of HIF-1α-induced vascular endothelial growth factorα expression in Huh7 cells. Moreover, this inhibition was in an MKK6/P38-dependent way. Besides, Huh7 subcutaneous tumor models in nude mice further demonstrated the inhibition of SSM on tumor weight might be exerted partly by reduction of angiogenesis via blocking MKK6/P38 signaling pathways.

Conclusion: SSM inhibits HCC-induced pro-angiogenesis under hypoxic conditions via suppression of MKK6/P38 signaling pathways, which is favorable for HCC tumor growth.

Keywords: HCC; MKK6/P38; SSM; hypoxia; pro-angiogenesis.