Additionally, the effects of shikonin on the survival and tumor growth of the nude mice model, as well as the migration and invasion of human CRC cells, appear to be able to imply the fact that shikonin inhibited the metastasis of CRC through SIRT2- (silent information regulators 2-) mediated antitumor effect (Zhang et al., 2017b). The gene discussed is SIRT2; the disease is neoplasm.