CD274 and gastric cancer: GEPIA (http://gepia.cancer-pku.cn/, accessed on 5 November 2022) analysis using Stomach data in the GTEx database suggested that the expression level of IL-6 was positively correlated with PDL1 expression (Pearson correlation r = 0.4), the M2 macrophage biomarker CD206 (Pearson correlation r = 0.2), and CD204 (Pearson correlation r = 0.42) but negatively correlated with the CD8-positive T-cell marker CD8A (Pearson correlation r = −0.19) (Figure 5H), suggesting that IL-6 participates in immune regulation in gastric cancer.