Intrinsic NPRL2 and NPRL3 regulate the sensitivity of B-cell malignancies to CAR-T cell therapy

Although chimeric antigen receptor (CAR) T-cell therapy has markedly improved outcomes for many patients with B-cell malignancies, a subset experiences limited benefit due to primary or secondary resistance. Building on CRISPR/Cas9 genome-wide screening in malignant B-cells, we identify NPRL2 and NPRL3 as key regulators of tumor sensitivity to CAR-T cytotoxicity. This study aims to investigate the impact and mechanisms of tumor-intrinsic NPRL2 and NPRL3 on the efficacy of CAR-T cell therapy. In a tandem CD19/20 CAR-T clinical trial for relapsed/refractory (R/R) B-cell lymphoma (NCT03097770), high tumor NPRL2 or NPRL3 expression correlates with therapeutic resistance in patients. Consistently, in vitro experiments confirm that tumor cells overexpressing NPRL2/NPRL3 exhibit resistance to CAR-T-mediated cytolysis. Mechanistically, NPRL2/NPRL3 suppresses mTORC1 activity within tumor cells, negatively regulating the conjugation between tumor cells and CAR-T cells, consequently impairing CAR-T cell activation and cytotoxic function, ultimately facilitating immune escape. As therapeutic strategies, either genetic ablation of tumor-intrinsic NPRL2/NPRL3 or pharmacological activation of mTORC1 enhances CAR-T cell activation, cytotoxic degranulation, and tumor clearance both in vitro and in vivo. In conclusion, targeting tumor NPRL2/NPRL3 or directly activating mTOR represents a promising combinational strategy to potentiate CAR-T efficacy and overcome resistance in clinical practice.