CXCL12 correlated with CD274 (R = 0.369) and PDCD1 (R = 0.288); CXCR4 correlated with CD274 (R = 0.579) and PDCD1 (R = 0.520), suggesting their roles in regulating immune checkpoints and tumor immune escape. This evidence concerns the gene PDCD1 and neoplasm.