PDCD1 and gastric cancer: The analysis indicated that expression of CXCR4 was significantly positively correlated to expression of CD274 (R = 0.31; p < 0.05), PDCD1 (R = 0.47; p < 0.05), CTLA4 (R = 0.62, p < 0.001), LAG3(R = 0.36; p < 0.05), CSF1(R = 0.53; p < 0.05) and NT5E (R = 0.14; p < 0.05)in GC (Figure 8A); and, expression of DLC1 was significantly positively correlated to expression of CD274 (R = 0.14; p < 0.05), PDCD1 (R = 0.19; p < 0.05) , CTLA4 (R = 0.25, p < 0.001), CSF1 (R = 0.69; p < 0.05) and NT5E (R = 0.26; p < 0.05) in GC (Figure 8B).