Epstein-Barr Virus Silences GSDME and Pyroptosis in Gastric Cancer

Epstein-Barr virus (EBV)-associated gastric carcinoma (EBVaGC) represents a distinct molecular subtype characterized by extensive DNA methylation and altered cell death signaling. This study investigated the regulation and function of gasdermin E (GSDME), a key mediator of pyroptosis, in EBVaGC. Transcriptomic analysis of The Cancer Genome Atlas (TCGA) data revealed that GSDME expression was selectively suppressed in EBV-positive gastric cancer, while other gasdermin family members were upregulated. Validation in multiple cell lines confirmed that EBV infection markedly reduced GSDME expression through promoter hypermethylation, which was reversed by treatment with the DNA methyltransferase inhibitor 5-azacytidine. EBV-positive cells exhibited enhanced caspase-3 activation and increased GSDME cleavage upon paclitaxel (PTX) exposure, leading to elevated lactate dehydrogenase (LDH) release and pyroptotic morphology. Overexpression of GSDME amplified, whereas siRNA-mediated knockdown or caspase-3 inhibition suppressed, PTX-induced pyroptosis without significantly altering overall cell viability. These findings demonstrate that EBV-induced epigenetic silencing of GSDME contributes to the modulation of chemotherapy-induced cell death, and that GSDME acts as a critical effector converting apoptosis to pyroptosis through caspase-3 activation. Collectively, our results reveal a novel link between EBV-driven DNA methylation and pyroptotic cell death, suggesting that restoration of GSDME expression may enhance therapeutic responses in EBV-associated gastric cancer.