Cinobufagin is an anticancer agent that can be secreted by the Asiatic toad Bufo gargarizans. Cinobufagin induces the cell cycle arrests in the G1 phase or G2/M phase, leading to apoptosis in cancer cells. Cinobufagin inhibits tumor growth in melanoma and glioblastoma multiforme xenograft mouse models[1][2][3].