Some researchers have found that CAR-T cells target two tumor-associated antigens at the same time, provide co-stimulation of CD28 and 4-1BB respectively, and share a CD3ζ chain, which can rapidly exert anti-tumor effects under in vivo stress conditions, protect tumors from re-attack, and prevent tumor escape due to low antigen density (14). This evidence concerns the gene TNFRSF9 and neoplasm.