Abstract

BACKGROUND Lung cancer remains one of the most lethal malignancies worldwide, with therapeutic resistance and low response rates representing major clinical challenges. The biosynthetic enzyme NFS1 has been implicated in tumour progression across various cancer types. PANoptosis is a recently identified type of cell death that can increase antitumour immunity, resulting in effective tumour suppression. Platycodin D (PD), a triterpenoid saponin isolated from the traditional Chinese medicine Platycodon grandiflorus, has demonstrated anticancer effects through mechanisms such as apoptosis induction and autophagy regulation. PURPOSE This study aimed to investigate the mechanism by which PD targets NFS1 to induce PANoptosis and increase antitumour immunity in lung cancer. METHODS The antiproliferative effect of PD was assessed using a CCK-8 assay. Changes in the expression of key PANoptosis-related proteins were analysed by Western blotting, and YP1/PI et al. were used to visualize different modes of cell death. CETSAs and DARTSs were performed to validate the direct interaction between PD and NFS1. ELISA and flow cytometry were used to measure the release of ICD-related molecules and DCs maturation, respectively. Mouse models were established to evaluate the in vivo antitumour efficacy and immunomodulatory effects of PD, both alone and in combination with NFS1 siRNA. RESULTS PD inhibited lung cancer cell proliferation in a dose-dependent manner. Mechanistically, PD directly bound to NFS1, downregulated its expression, and induced significant accumulation of ROS, leading to the activation of PANoptosis. Furthermore, PD treatment triggered the release of ATP and HMGB1, and promoted DCs maturation. In vivo studies confirmed that PD significantly suppressed tumour growth and acted synergistically with NFS1 knockdown to promote antitumour immunity.