Overexpression of these proteins contributes to apoptosis resistance in different tumors, including melanoma,27,42 by inhibition of both initiator and effector caspases.43 Interestingly, we found that the combinatorial treatments induced a strong downmodulation of c-IAP1, c-IAP2, XIAP and Apollon, and this may contribute to explain the significant activation of caspase-3/7 that we observed. Here, XIAP is linked to melanoma.