Inetetamab, a novel anti-HER2 monoclonal antibody, exhibits potent synergistic anticancer effects with cisplatin by inducing pyroptosis in lung adenocarcinoma

Cisplatin is a first-line chemotherapy drug for lung adenocarcinoma (LUAD). However, its therapeutic efficacy is limited because of serious side effects and acquired drug resistance. Targeting HER2 has been proven to be a viable therapeutic strategy against LUAD. Moreover, inetetamab, an innovative anti-HER2 monoclonal antibody, has a more potent antibody-dependent cell-mediated cytotoxicity (ADCC)-inducing effect than trastuzumab, which has been shown to be an effective and rational strategy in the clinic when combined with multiple chemotherapeutic agents. Thus, the present study aimed to explore the synergistic effects of cisplatin (DDP) and inetetamab in LUAD cells and investigate the detailed underlying mechanisms. Here, in vitro and in vivo, we found that the combination of inetetamab and cisplatin induced synergistic effects, including induction of pyroptosis, in LUAD. Mechanistic studies revealed that inetetamab combined with cisplatin inhibited HER2/AKT/Nrf2 signaling to increase ROS levels, which triggered NLRP3/caspase-1/GSDMB-mediated pyroptosis to synergistically enhance antitumor efficacy in LUAD cells. In addition, cisplatin enhanced the PBMC-killing ability of inetetamab by inducing GSDMB-mediated pyroptosis, which can be explained by increased secretion of IFN-γ. Our study reveals that the anti-HER2 monoclonal antibody inetetamab may be an attractive candidate for LUAD therapy, which opens new avenues for therapeutic interventions for LUAD.