Extract of Rhus verniciflua Stokes Induces p53-Mediated Apoptosis in MCF-7 Breast Cancer Cells

Rhus verniciflua Stokes has long been used as a food supplement and traditional herbal medicine for various ailments in East Asia. We evaluated the anticancer effects of Rhus verniciflua Stokes extract (RVSE) on MCF-7 cells by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay, flow cytometry, annexin V/7-AAD staining, and western blotting. In addition, the gallic acid content of RVSE was assayed using high-performance liquid chromatography. RVSE inhibited the growth of MCF-7 cells in a dose-dependent manner by inducing apoptosis in the sub-G1 phase. RVSE also significantly increased the number of apoptotic cells and increased the expression of p53 and p21 in a dose-dependent manner. Furthermore, RVSE treatment increased the Bax:Bcl-2 ratio and the levels of apoptosis-related factors, such as cleaved caspase-3 and -9 and PARP, in MCF-7 cells. Our findings suggest that the proapoptotic effect of RVSE on MCF-7 cells is mediated by p53, p21, and the intrinsic mitochondrial cascade. Thus, RVSE shows promise for the prevention and treatment of breast cancer.