CD247 and neoplasm: Typically, CARs are composed of four segments (Figure 1 A), including an extracellular domain usually containing a single-chain variable fragment (scFv) derived from the variable region of antibodies for tumor antigen recognition, an extracellular spacer regulating the distance between CAR-T cells and tumor cells, a transmembrane domain gluing the synthetic CARs to patient's T cell membrane, and an intracellular signaling domain which consists CD3ζ and costimulatory domains for T cell activation9-14.