Five cycloartane triterpenoids were also identified to act at mitochondrial level when tested on the breast cancer cell line MCF-7 and its corresponding drug resistant subline R-MCF-7 (143); the five compounds isolated from Cimicifuga yunnanensis P.K.Hsiao stimulated the expression of p53 and Bax, resulting in the loss of mitochondrial potential and, subsequently, the activation of caspase-7, followed by apoptosis and cell death. The gene discussed is TP53; the disease is breast cancer.