Sphingomonas paucimobilis ‐Driven Epithelial–Endothelial Transition in Adenomyosis Pathogenesis

Adenomyosis is a common gynecological disorder with incompletely understood pathogenesis. Through single-cell RNA sequencing of adenomyosis tissues, we identified epithelial-endothelial transition (EET) as a key pathological mechanism and discovered transitional cells co-expressing epithelial (EPCAM) and endothelial (PECAM1) markers. Using CSI-Microbes pipeline and 2bRAD-M validation, we found significant enrichment of Sphingomonas paucimobilis in adenomyosis lesions with spatial co-localization to EET cells. Mouse experiments confirmed that vaginal inoculation with live S. paucimobilis recapitulated adenomyosis development, indicating that viable bacteria are required. Systematic inhibitor experiments validated a TNFα → NF-κB → MMP signaling cascade: TNFα neutralization and NF-κB inhibition blocked pathway activation and EET, while MMP inhibition attenuated downstream phenotypic changes. Protein-level validation by Western blot and immunofluorescence across human tissue, mouse models, and cell culture confirm EET marker changes. This study elucidates a novel microbial-driven cellular transformation mechanism and identifies actionable therapeutic targets for adenomyosis.