Dietary urolithin A suppresses lung cancer via gut microbiota-mediated autophagy activation.

Urolithin A (UA), a gut microbiota-derived metabolite of ellagic acid, exhibits diverse biological activities. Emerging evidence suggests its anti-tumor potential, possibly mediated through gut microbiota modulation, yet its role in lung cancer remains unclear. In this study, UA dose- and time-dependently suppressed lung cancer cell proliferation. Mechanistically, UA triggered autophagy, as evidenced by increased LC3-II protein levels, and transcriptome analysis revealed this effect was mediated through inhibition of the PI3K/AKT/mTOR pathway. In vivo, UA supplementation markedly inhibited tumor growth in H1975 xenograft models, concomitant with enhanced autophagy and downregulation of associated proteins. Notably, 16S rRNA sequencing demonstrated that UA modulated gut microbiota composition, increasing Lactobacillus while decreasing Desulfovibrio abundance. Spearman's correlation analysis further linked these microbial shifts to altered expression of autophagy-related genes. Collectively, our findings highlight UA as a promising gut microbial metabolite for lung cancer intervention via coordinated autophagy induction and microbiota remodeling.