Tarannum et al. engineered mesothelin-targeted CAR-NK cells secreting IL-12 tethered to a collagen-binding A3 domain to spatially restrict IL-12 activity within the collagen I/III-rich TIME. IL-12 and CAR signaling converged through Ras-ERK and PI3K pathways to sustain mTORC1 activity, enhancing CAR-NK cell activation, proliferation, and metabolic fitness. Matrix-anchored IL-12 CAR-NK cells also activated bystander NK cells, T cells, and macrophages, without expanding Tregs. In ovarian and pancreatic cancer models, IL-12 CAR-NK cells achieved potent and durable antitumor responses, with limited systemic IL-12 toxicity.

Contributed by Shishir Pant

ABSTRACT: Solid tumors evade immunotherapy because of immunosuppressive microenvironments that limit immune cell persistence and function. Although interleukin-12 (IL-12) potently activates antitumor immunity, its clinical use has been constrained by systemic toxicity. Here we engineered a CAR natural killer (NK) cell platform that integrated IL-12 signaling to enhance antitumor immunity. IL-12 signaling synergized with CAR activation to sustain mTORC1 activity through convergent Ras-ERK and PI3K pathways, promoting metabolic fitness, autonomous expansion, and sustained effector function. IL-12 also activated bystander NK cells, T cells, and macrophages to remodel the tumor microenvironment. To improve safety, IL-12 was tethered to a collagen-binding A3-domain, restricting its activity to the extracellular matrix and limiting systemic exposure. In ovarian and pancreatic cancer models, matrix-anchored IL-12 CAR NK cells expanded without exogenous cytokines and achieved durable tumor control. These findings suggest that mTORC1-mediated integration of CAR and cytokine signaling can enhance immune fitness and overcome immunosuppressive tumor microenvironments.

Author Info: (1) Dana-Farber Cancer Institute Boston, MA United States. ROR: https://ror.org/02jzgtq86 (2) Dana-Farber Cancer Institute Boston, MA United States. ROR: https://ror.org/02jzgtq86 (3) University of Pittsburgh Pittsburgh, PA United States. ROR: https://ror.org/01an3r305 (4) Dana-Farber Cancer Institute United States. ROR: https://ror.org/02jzgtq86 (5) Dana-Farber Cancer Institute Boston, MA United States. ROR: https://ror.org/02jzgtq86 (6) Dana-Farber Cancer Institute Boston, MA United States. ROR: https://ror.org/02jzgtq86 (7) Dana Farber Cancer Institute Boston United States. (8) Dana-Farber Cancer Institute United States. ROR: https://ror.org/02jzgtq86 (9) Dana-Farber Cancer Institute Boston, MA United States. ROR: https://ror.org/02jzgtq86 (10) Dana-Farber Cancer Institute Boston, MA United States. ROR: https://ror.org/02jzgtq86 (11) Dana-Farber Cancer Institute Boston, MA United States. ROR: https://ror.org/02jzgtq86 (12) Dana-Farber Cancer Institute Boston, MA United States. ROR: https://ror.org/02jzgtq86 (13) Dana-Farber Cancer Institute Boston, MA United States. ROR: https://ror.org/02jzgtq86 (14) Dana-Farber Brigham Cancer Center Boston, MA United States. ROR: https://ror.org/05rgrbr06 (15) Dana-Farber Cancer Institute Boston United States. ROR: https://ror.org/02jzgtq86 (16) Dana-Farber Cancer Institute Boston, MA United States. ROR: https://ror.org/02jzgtq86 (17) Dana-Farber Cancer Institute United States. (18) Dana-Farber Cancer Institute Boston, MA United States. ROR: https://ror.org/02jzgtq86 (19) Dana-Farber Cancer Institute Boston, MA United States. ROR: https://ror.org/02jzgtq86 (20) Dana-Farber Cancer Institute Boston, Massachusetts United States. ROR: https://ror.org/02jzgtq86 (21) Dana-Farber Cancer Institute Boston United States. ROR: https://ror.org/02jzgtq86 (22) Skyline Therapeutics Cambridge, MA United States. (23) University of Cincinnati Medical Center Cincinnati United States. ROR: https://ror.org/02p72h367 (24) Dana-Farber Cancer Institute Boston, MA United States. ROR: https://ror.org/02jzgtq86 (25) Dana-Farber Cancer Institute Boston, MA United States. ROR: https://ror.org/02jzgtq86 (26) Dana-Farber Cancer Institute Boston, MA United States. ROR: https://ror.org/02jzgtq86 (27) Dana-Farber Cancer Institute Boston, MA United States. ROR: https://ror.org/02jzgtq86 (28) Dana-Farber Cancer Institute Boston, MA United States. ROR: https://ror.org/02jzgtq86 (29) Dana-Farber Cancer Institute Boston, Massachusetts United States. ROR: https://ror.org/02jzgtq86 (30) Dana-Farber Cancer Institute Boston United States. ROR: https://ror.org/02jzgtq86 (31) Dana-Farber Cancer Institute Boston, MA United States. ROR: https://ror.org/02jzgtq86 (32) Dana-Farber Cancer Institute Boston, MA United States. ROR: https://ror.org/02jzgtq86 (33) Dana-Farber Cancer Institute Boston, MA United States. ROR: https://ror.org/02jzgtq86 (34) Massachusetts Institute of Technology Cambridge, MA United States. ROR: https://ror.org/042nb2s44 (35) Dana-Farber Cancer Institute, Harvard University Boston, MA United States.