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 <i>GSDME</i> 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 <i>GSDME</i> 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 <i>GSDME</i> 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 <i>GSDME</i> 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 <i>GSDME</i> expression may enhance therapeutic responses in EBV-associated gastric cancer.