The previous study had shown that when elongating two second-generation CD28/4-1BB/CD3ζ CARs by a DAP10 domain, these CAR-T cells showed superior antitumor activity against other cancers, such as gastric cancer, lung cancer, and hepatocellular carcinoma, in xenograft-bearing mice [30, 31]. This evidence concerns the gene CD28 and gastric cancer.