In a phase II clinical trial, the gp100 peptide vaccine used alone had little antitumor activity.1 Rosenberg et al. also reported that the overall clinical response rate of cancer peptide vaccines was extremely low (only 2.6% among 440 cancer patients).2 To solve this problem, great efforts have been devoted to exploit novel immunomodulators or vaccine adjuvants. The gene discussed is PMEL; the disease is cancer.