To confirm the involvement of functional GSTP1 and MRP1 in the observed resistance of A375 melanoma cell to etoposide, we studied the effects of GSTP1 AS RNA expression, and of pharmacological inhibitors (curcumin, ethacrynic acid, BSO, sulfinpyrazone, MK571), on [3H]-etoposide accumulation. This evidence concerns the gene GSTP1 and melanoma.