IL7 and neoplasm: Recently, numerous strategies have been developed to potentiate CAR-T cells toward corresponding solid tumors by promoting their tumor infiltration and persistence via genetic engineering to express immunostimulatory cytokines (e.g. interleukin-7/10/15, C–C motif chemokine 19/21) and downregulate immunosuppressive molecules (e.g. programmed cell death protein 1, transforming growth factor-β) or modulating the tumor microenvironment with different functional biomaterials [8–14].