FAP expression was positively related to the expression levels of immune checkpoint genes in different kinds of cancers, including colon adenocarcinoma (COAD), thyroid cancer, STAD, and liver hepatocellular carcinoma (LIHC), indicating that FAP may have a potential effect on modulating tumor immune pattern in some cancers by modulating the immune checkpoint genes expression levels (Figure 1B). This evidence concerns the gene FAP and gastric adenocarcinoma.