Abstract
Immunotherapy has revolutionized cancer treatment, yet challenges persist, such as resistance and lethal thromboembolism, necessitating dual-purpose strategies. Targeting ferroptosis emerges as a promising strategy to enhance immunotherapy efficacy, prompting our investigation of antiplatelet agents that simultaneously promote ferroptosis and mitigate thromboembolic risks. Through systematic screening of 20 Food and Drug Administration (FDA)-approved antiplatelet agents, we identify vorapaxar as a potent pro-ferroptotic drug. Mechanistically, vorapaxar binds forkhead box O1 (FOXO1), inhibits its phosphorylation at Ser256, and facilitates nuclear translocation to upregulate heme oxygenase 1 (HMOX1), promoting mitochondrial iron overload and mitochondria-associated ferroptosis. Vorapaxar enhances immunotherapy-induced tumor ferroptosis and antitumor immunity across diverse melanoma models, including B16F10 tumor-bearing mice, Braf/Pten-driven spontaneous melanoma mice, and peripheral blood mononuclear cell (PBMC)-humanized mice. Clinically, high FOXO1/HMOX1 co-expression correlates with improved immunotherapy response and progression-free survival. These findings position vorapaxar as a promising adjunct to immunotherapy, offering a dual benefit for cancer patients requiring both antithrombotic therapy and immunotherapy.