Interestingly, we noted the significant correlation between DDR1 level and Treg and T cell exhaustion markers like CCR8, PD-1, CTLA-4, and TIM-3 (Table 2), revealing that DDR1 might play a potential role in immune escape in STAD, but further studies are needed about its mechanisms. This evidence concerns the gene CTLA4 and gastric adenocarcinoma.