In a melanoma cell (B16)-injected C57BL/6 mouse model, a delivery of artificially combined siRNA targeting programmed cell death protein 1(PD-1-siRNA) and cytosine-phosphate-guanine oligodeoxynucleoties (CpG ODN) effectively reduced tumor size, and exhibited the longest survival, as compared with any single delivery of either siRNA or CpG ODN TLR agonist. Here, PDCD1 is linked to neoplasm.