TGFB1 and neoplasm: CAR-NK cells pro-tumor effects are contributed by their ability to release of immunosuppressive cytokines (e.g., TGF-β, adenosine and indoleamine 2,3-dioxygenase) within immuno-suppressive TME, and also to express inhibitory receptors (e.g., TIGIT, PD-1, CTLA-1, NKG2A, CISH) [170, 171].