Tumoricidal Efficacy of Artesunate-Eluting Microsphere: Differential Role of Bax/Bak in Orchestration of Cell Death Pathways

Artesunate (ART), an antimalarial drug, has been identified as a ferroptotic agent, inducing the generation of reactive oxygen species (ROS) and lipid peroxidation, which, in turn, activate endoplasmic reticulum (ER) stress responses and promote mitochondrial-dependent apoptosis. In our previous studies, we demonstrated that ART enhances tumor necrosis factor-related apoptosis-inducing ligand (TRAIL)-induced apoptosis through crosstalk between the ER stress-mediated signal pathway and the Bid-Bax mitochondrial apoptotic cascade. To further explore the mechanisms underlying ferroptotic-apoptotic crosstalk and evaluate the potential of intra-arterial drug-eluting microspheres for targeted tumor therapy, we developed artesunate-eluting microspheres (ART-EMs) and investigated the tumoricidal efficacy of ART-EMs combined with TRAIL. Our findings reveal that the combined ART-EMs with TRAIL (AT) treatment synergistically enhances cancer cell death. Specifically, we observed increased apoptosis in HCT116 and BxPC-3 cell lines, accompanied by notable morphological changes and enhanced cytotoxicity. Importantly, our results demonstrate that the pro-apoptotic proteins Bid and Bax play essential roles in driving synergistic apoptosis during AT treatment. Furthermore, the contrasting apoptotic responses between AT treatment and the chemotherapeutic agent mitomycin C's dependence on p53-Bak-associated pathways underscore the differential activation of intrinsic apoptosis pathways across cancer cell lines. This study provides deeper insight into the roles of Bak and Bax in orchestrating apoptosis, offering potential strategies for more effective cancer treatments.