%0 Journal Article %T Disrupting Smad3 potentiates immunostimulatory function of NK cells against lung carcinoma by promoting GM-CSF production. %A Lian GY %A Wang QM %A Mak TS %A Huang XR %A Yu XQ %A Lan HY %J Cell Mol Life Sci %V 81 %N 1 %D 2024 Jun 15 %M 38878186 %F 9.207 %R 10.1007/s00018-024-05290-4 %X Through Smad3-dependent signalings, transforming growth factor-β (TGF-β) suppresses the development, maturation, cytokine productions and cytolytic functions of NK cells in cancer. Silencing Smad3 remarkably restores the cytotoxicity of NK-92 against cancer in TGF-β-rich microenvironment, but its effects on the immunoregulatory functions of NK cells remain obscure. In this study, we identified Smad3 functioned as a transcriptional repressor for CSF2 (GM-CSF) in NK cells. Therefore, disrupting Smad3 largely mitigated TGF-β-mediated suppression on GM-CSF production by NK cells. Furthermore, silencing GM-CSF in Smad3 knockout NK cells substantially impaired their anti-lung carcinoma effects. In-depth study demonstrated that NK-derived GM-CSF strengthened T cell immune responses by stimulating dendritic cell differentiation and M1 macrophage polarization. Meanwhile, NK-derived GM-CSF promoted the survival of neutrophils, which in turn facilitated the terminal maturation of NK cells, and subsequently boosted NK-cell mediated cytotoxicity against lung carcinoma. Thus, Smad3-silenced NK-92 (NK-92-S3KD) may serve as a promising immunoadjuvant therapy with clinical translational value given its robust cytotoxicity against malignant cells and immunostimulatory functions to reinforce the therapeutic effects of other immunotherapies.