GEFT inhibits the GSDM-mediated proptosis signalling pathway, promoting the progression and drug resistance of rhabdomyosarcoma.

The metastasis or recurrence of rhabdomyosarcoma (RMS) is the primary cause of tumour-related deaths. Patients with high-risk RMS have poor prognosis with a 5-year overall survival rate of 20-30%. The lack of specific drug-targeted therapy and chemotherapy resistance are the main reasons for treatment failure. Drugs or molecular target inhibitors can induce the pyroptosis of tumour cells or increase their sensitivity to chemotherapy, making pyroptosis an effective strategy for antitumour therapies. Pyroptosis is mediated by gasdermin (GSDM) family members. Here, we found that the expression of NLRP3, caspase-1, caspase-3, GSDMD and GSDME in RMS was remarkably lower than that in skeletal muscle tissues. Nigericin and dactinomycin in RMS cells achieved their regulatory effect on pyroptosis through the NLRP3/caspase-1/GSDMD pathway and caspase-3/GSDME pathway, respectively. Necrosulfonamide reversed the pyroptosis-related changes induced by nigericin, and siGSDME converted the dactinomycin-induced pyroptosis into apoptosis. Additionally, GEFT inhibited the GSDMD and GSDME pyroptosis pathways, thereby promoting the progression and drug resistance of RMS. Mouse xenograft and tumour analysis confirmed that nigericin and dactinomycin can effectively improve the therapeutic effect of RMS by activating the pyroptosis pathway. To the best of our knowledge, this study was the first to focus on pyroptosis in RMS. Overall, our investigation demonstrated that nigericin and dactinomycin play therapeutic roles in tumours by promoting RMS cell pyroptosis. Interference with GEFT and drug combination can exert a great inhibitory effect on tumours.