The percentage of LAG-3+ cells was significantly elevated in tumor-infiltrating CD8+ T cells (80.27 ± 6.89%) when compared with peripheral CD8+ T cells either from NC (64.67 ± 7.43%, LSD-t test, P = 0.0001, Fig. 4b) or from GC patients (66.18 ± 8.57%, LSD-t test, P = 0.0004, Fig. 4b). This evidence concerns the gene CD8A and gastric cancer.