PROM1 and neoplasm: With Cu(I) available, hypoxic tumor cells activates HIF-1 [22, 23, 84, 87], triggering a series of effects including promotion of CD133+ CSCs via survival advantages [20, 22, 23, 57, 84, 87, 93], which also enhances the self-renewal ability and inhibits differentiation of CSCs [22, 84, 106].