Gaudichaudione H induces GSDME-mediated pyroptosis and apoptosis in esophageal squamous cell carcinoma via ROS-dependent YAP degradation.

BACKGROUND: Esophageal squamous cell carcinoma (ESCC) is an aggressive malignancy with limited therapeutic options. Therefore, novel treatment strategies are urgently needed. PURPOSE: This study aimed to evaluate the antitumor effects of Gaudichaudione H (GH), a natural caged xanthone isolated from Garcinia oligantha Merr., and to elucidate its underlying mechanisms with a focus on cell death regulation in ESCC. METHODS: The antitumor activity of GH was evaluated in ESCC cell lines (KYSE150, KYSE450, Eca-109) and a xenograft mouse model. Cell viability, LDH release, morphological changes, and protein expression were assessed. RNA sequencing, pharmacological inhibitors, and genetic manipulation of YAP (knockdown and overexpression) were used to investigate the underlying mechanism. RESULTS: GH exhibited dose-dependent cytotoxicity against ESCC cell lines, with IC₅₀ values ranging from 5.7 to 7.9 μM in KYSE150, KYSE450, and Eca-109 cells. GH induced apoptotic and pyroptotic morphological features accompanied by increased LDH release in a caspase-3-dependent manner. Transcriptomic analysis revealed enrichment of the MAPK/JNK signaling pathway. Mechanistically, GH elevated intracellular ROS levels, leading to ubiquitin-proteasome-dependent degradation of YAP. Loss of YAP activated JNK signaling, resulting in caspase-3 activation and GSDME cleavage. ROS scavenging or JNK inhibition significantly attenuated GH-induced cell death. In vivo, GH inhibited tumor growth by approximately 75% compared with the vehicle-treated group in a xenograft model without observable systemic toxicity. CONCLUSION: GH induces ESCC cell death through a ROS-dependent YAP ubiquitination axis involving JNK signaling activation, which regulates the crosstalk between apoptosis and pyroptosis in ESCC. These findings highlight GH as a promising natural lead compound for ESCC therapy. ABBREVIATIONS: CHX, Cycloheximide; DMSO, Dimethyl sulfoxide; ECL, Enhanced chemiluminescence; ESCC, Esophageal squamous cell carcinoma; GSDME, Gasdermin E; GH, Gaudichaudione H; JNK, c-Jun N-terminal kinase; KEGG, Kyoto Encyclopedia of Genes and Genomes; LDH, Lactate dehydrogenase; MAPK, Mitogen-activated protein kinase; NAC, N-acetylcysteine; PARP, Poly(ADP-ribose) polymerase; PBS, Phosphate-buffered saline; PCD, Programmed cell death; PPI, Protein-protein interaction; RNA-seq, RNA sequencing; ROS, Reactive oxygen species; siRNA, Small interfering RNA; YAP, Yes-associated protein.