PDCD1 and neoplasm: Furthermore, the B2M‐Overexpression group exhibited smaller tumor volumes and lighter tumor weight than those in the vehicle and B2M‐Sh2 groups in both murine models of “hot tumor” (Figure 5H,I).[34] Next, we analyzed the characteristics of tumor‐infiltrating lymphocytes (TILs) and found similar results: the infiltration proportions of CD8+ T cells rather than CD4+ T cells were significantly increased (Figure 5J,K) and the expression of PD‐1 in CD8+ T cells was also increased in the B2M‐Overexpression group compared to the vehicle group (Figure 5L,M).