MIT and collaborators published preclinical data showing polymer‑coated nanoparticles that deliver IL‑12 into the tumor microenvironment markedly enhanced checkpoint inhibitor activity and eliminated metastatic ovarian tumors in more than 80% of mice. The IL‑12‑releasing design concentrates cytokine at tumor sites, reducing systemic exposure while promoting durable anti‑tumor immunity and immune memory on rechallenge, the team reported in Nature Materials. Senior authors Paula Hammond and Darrell Irvine described a surface‑borne payload strategy that effectively ‘‘tricks’’ tumor cells into presenting IL‑12 to immune effectors, enabling T cells to mount potent responses when combined with PD‑1/PD‑L1 blockade. The study included tumor elimination, survival, and immune memory endpoints, supporting translation toward intraperitoneal and loco‑regional cytokine therapies.