Oligoclonal tumor-specific CD8 T-cell revival and IRE1α/XBP1-GDF15-mediated immunosuppressive niches determine neoadjuvant chemoimmunotherapy efficacy in cervical cancer.

BACKGROUND: Neoadjuvant chemoimmunotherapy (NACI) shows promise for locally advanced cervical cancer (LACC), but drug-tolerant persister (DTP) cells and immunosuppressive microenvironmental adaptations limit clinical efficacy. The underlying determinants governing heterogeneous responses to NACI regimens remain poorly understood, particularly regarding how dynamic tumor-immune interactions shape therapeutic outcomes. METHODS: We characterized microenvironmental dynamics in patients with LACC by integrating single-cell RNA sequencing (RNA-seq), single-cell VDJ sequencing (n=10, five paired pre-NACI/post-NACI samples) and spatial transcriptomics (ChiCTR2300072535). Pathological response was assessed using major pathological response criteria. The findings were validated in an independent NACI cohort (n=23 with RNA-seq), multiplex immunohistochemistry (mIHC) analysis of six surgically resected specimens, as well as functional in vitro and murine models. RESULTS: MPR patients exhibited cytotoxic revival via oligoclonal expansion of tumor-reactive CD8+T cell clones and CCR5-mediated myeloid-T cell crosstalk. Conversely, non-MPR tumors exhibited endoplasmic reticulum (ER) stress-adapted DTP cells with elevated ER stress signaling, accompanied by a deficiency in tumor-specific T-cell clone expansion and an accumulation of transforming growth factor beta receptor 2 (TGFBR2) + myeloid DTP niches. Mechanistically, ER stress signaling via the inositol‑requiring enzyme 1 alpha (IRE1α) / X‑box binding protein 1 (XBP1) axis induces growth differentiation factor 15 (GDF15) production in DTP cells, contributing to treatment‑resistant microdomains. Pharmacological IRE1α inhibition synergized with chemoimmunotherapy to eradicate DTP populations in murine models. CONCLUSIONS: This study provides critical insights that NACI resistance stems from adaptive ER stress signaling in DTP cells and spatially organized immunosuppressive networks. Targeting the IRE1α/XBP1-GDF15 axis represents an actionable strategy to reprogram microenvironmental ecology and improve immunotherapy outcomes.