[Antitumor effect of the plant alkaloid preparation, cepharanthin]

The antitumor effect of cepharanthin (CR), a biscoclaurine alkaloid, was examined as to its direct action on tumor cells and inhibitory action on angiogenesis in tumors. The effect of CR on in vitro invasion by murine RL-[symbol: see text] 1 leukemia cells and Colon 26 tumor cells was studied using a biocoat matrigel invasion chamber. One hundred micrograms/ml of CR inhibited tumor cell invasion. Early induction of apoptosis was assayed by the binding of annexin V and phosphatidylserine (PS) in the cellular membrane CR (10 and 100 micrograms/ml) induced apoptosis in human Daudi and Raji B lymphoblastoid cells. Treatment with CR (1 and 10 micrograms/ml) also inhibited the in vitro growth of Daudi and Raji cells. Ten micrograms/ml of CR also inhibited the growth of human umbilical vein endothelial cells (HUVEC) and human dermal microvascular endothelial cells (HMVEC). These results indicate that CR has diversified antitumor functions, i.e., an enhancement of a sequential immune mechanism, a direct cytotoxic effect and inhibitory action of angiogenesis in tumors.