San Huang Decoction Targets Aurora Kinase A to Inhibit Tumor Angiogenesis in Breast Cancer

San Huang Decoction (SHD), a Chinese herb formula, has been popularly prescribed in the clinical treatment of patients suffering from breast cancer. The aim of this study was to explore the anti-angiogenic effects of SHD in breast cancer and explain the underlying mechanism. Transwell and Matrigel assays showed that SHD reduced human umbilical vein endothelial cell migration and tubule formation and ELISA and qRT-PCR assays demonstrated its mediation of vascular endothelial growth factor (VEGF) expression. siRNA silencing of aurora kinase A (AURKA) produced results similar to those obtained by inhibition of AURKA with SHD. In addition, a chorioallantoic membrane assay was carried out to directly examine the effect of SHD on breast cancer anti-angiogenesis and immunofluorescence and immunohistochemical staining analysis showed that SHD reduced the expression of CD31, AURKA, and VEGF in a xenograft model. Furthermore, SHD regulated extracellular signal-regulated kinase expression in breast cancer cells, which was examined by western blotting. In conclusion, our findings indicated that SHD treatment mimicked the decrease in tumor neovascularization in breast cancer cells after the siRNA-mediated knockdown of AURKA. Thus, SHD may inhibit tumor angiogenesis in breast cancer by targeting AURKA and downregulating the ERK signaling pathway.