TGFBR2 and small cell lung carcinoma: Knockout TGFBR2 in NK cells can enhance their in‐vitro and in‐vivo cytotoxic effect on lung cancer[36] and glioblastoma.[37] In addition, blockade of the TGF‐β signaling pathway can inhibit SCLC metastasis.[28] This implied that immunotherapy targeting TGFBR2+ NK cells may offer a promising treatment of SCLC by killing and preventing metastasis of malignant cells.