We elucidated that IL-27 augments the expression of TRAIL and TLR3 together with RIG-I and MDA5 in human melanomas, and that IL-27 and a TLR3 agonist, poly(I:C), cooperatively enhance TRAIL expression and inhibit their tumor growth partly in a TRAIL-dependent manner as illustrated in Fig. 6. Here, IFIH1 is linked to melanoma.