The results showed that CASC2 knockdown reduced the apoptosis rate of tumor cell; miR-24 or miR-221 inhibition promoted the apoptosis rate; the inhibitory effect of CASC2 knockdown on tumor cell apoptosis could be significantly reversed by miR-24 inhibition or miR-221 inhibition (Figs. 6e,f). This evidence concerns the gene CASC2 and neoplasm.