Previously, we reported a novel cell-penetrating peptide (CPP), dNP2, which delivers an immune regulatory protein into T cells and showed its therapeutic potential in autoimmune diseases20,21 We hypothesized that introducing siRNA against Chi3l1 (siChi3l1) via dNP2 peptide would be a novel strategy and could enhance anti-tumor immunity to reject tumors. The gene discussed is CHI3L1; the disease is neoplasm.