The knockdown of ALDH2 by specific siRNA was found to potentiate the sensitivity of CT26 tumors to anti‐PD‐1 antibody, leading to a dramatically reduction in tumor burden (p < 0.01, Student's t‐test; Figure 5N–R; Figure S4B–G, Supporting Information), and improved overall survival compared with anti‐PD‐1 treatment alone (p < 0.05, Student's t‐test; Figure 5S). This evidence concerns the gene ALDH2 and neoplasm.