Our results indicate that CaM binding is necessary for the anti-cancer effects of CWHM-974 because: 1) We demonstrate that CWHM-974 directly binds to CaM; 2) CALM1 expression significantly correlates with sensitivity to both FLU and CWHM-974; 3) the sulfoxide derivative of CWHM-974, which lacks CaM binding activity, had no anti-cancer effects; and 4) sensitivity to both FLU and CWHM-974 significantly correlates with sensitivity to the CaM inhibitor W-7. Here, CALM3 is linked to cancer.