CELL INTELLIGENCE · 肿瘤细胞治疗研究

Natural Killer (NK) cell-based immunotherapy relies on CD16-mediated Antibody-Dependent Cellular Cytotoxicity (ADCC), yet the ovarian tumor microenvironment (TME) severely compromises this function via Transforming Growth Factor-beta (TGF- ). This study investigated the molecular mechanisms driving this suppression and evaluated a bi-specific Chimeric Antigen Receptor (CAR) strategy to overcome this hurdle. Primary PBNK cells exposed to TGF- showed sustained canonical SMAD2 phosphorylation, accompanied by a marked reduction in activating receptors such as CD16 and NKG2D and an increase in exhaustion markers such as PD-1. Functionally, these phenotypic alterations led to failed infiltration and cytotoxicity in vitro and within ovarian cancer-derived spheroids. To overcome this limitation, we engineered NK-92 cells with a bi-specific CAR-targeting Folate Receptor Alpha (FR ) and CD16. While TGF- typically impairs NK cell function, our armed CAR-NK cells successfully infiltrated tumoroids and synergized with Trastuzumab to induce potent ADCC-mediated lysis. Our findings define the TGF- /SMAD2 axis as a central driver of NK cell dysfunction in ovarian cancer and demonstrate that bi-specific CAR-NK platforms offer a robust therapeutic solution to bypass TME-induced suppression and restore antibody-mediated tumor suppression.