PDCD1 and gastric cancer: Subsequently, in patients with Stage III GC, ACT provided a significant survival benefit in both PD-1+CD8+ T cells high-infiltration subgroup (P < 0.001, HR = 0.35; Fig. 3c) and PD-1+CD8+ T cells low-infiltration subgroup (P < 0.001, HR = 0.21; Fig. 3c).