In line with this, a recent study described that simultaneous down-regulation of PD1 and TIGIT exerted a synergistic anti-tumor effect, the down-regulation of TIGIT was mainly responsible for maintaining the low-differentiation and low-exhaustion state of CAR T cells, while the down-regulation of PD1 enhanced the short-term cytotoxicity of CAR T cells in vitro functional assays (Lee et al., 2022). This evidence concerns the gene TIGIT and neoplasm.