PDCD1 and neoplasm: It has been shown that the therapeutic use of PD-1 leads to an increase in the expression level of LAG-3 [80]. In NSCLC, the co-expression of LAG-3 and PD-1 on TILs and PD-L1 on tumor cells is shown [81]. A synergistic effect was observed from the combined use of mAbs binds LAG-3 and PD-1 in various tumor models [82].