Amsilarotene (TAC-101; Am 555S), an orally active synthetic retinoid, has selective affinity for retinoic acid receptor α (RAR-α) binding with Ki of 2.4, 400 nM for RAR-α and RAR-β. Amsilarotene induces the apoptotic of human gastric cancer, hepatocellular carcinoma and ovarian carcinoma cells. Amsilarotene can be used for the research of cancer.