Furthermore, TIGIT and/or PD-1 expression in CD8+T cells is increased in patients with gastric cancer relapse after treatment with SOX (S-1 and oxaliplatin) regimen, whereas no notable increase in the proportion of TIGIT+ and/or PD-1+CD8+T cells was found in relapse-free patients [60]. This evidence concerns the gene PDCD1 and gastric cancer.