siRNA targeting iP beta subunits (LMP2, LMP7, and MECL1) is used to modify the expression of iP-mediated antigen processed by dendritic cells, in combination with RNAs encoding melanoma TAAs (MART-1, tyrosinase, gp100, and MAGE-3), to enhance antigen-specific T cell responses. This evidence concerns the gene PSMB9 and melanoma.