Halofuginone Disrupted Collagen Deposition via mTOR‐eIF2α‐ATF4 Axis to Enhance Chemosensitivity in Ovarian Cancer

The interplay between cancer-associated fibroblasts (CAFs) and extracellular matrix (ECM) mediates progress, metastasis, and therapy resistance. However, strategy of targeting ECM remodeling to enhance chemosensitivity in ovarian cancer remains elusive. Here, a 22-gene matrisome signature predicts chemotherapy response and survival in ovarian cancer. The dense, collagen-rich ECM secreted by CAFs harbors more M2 tumor-associated macrophages (TAMs) than the looser ECM based on single cell RNA-seq (scRNA-seq) of ovarian cancer, suggesting the promising approach of targeting collagen to remodel ECM. An integrated analysis identifies collagen type I alpha 1 chain (COL1A1) as a major component of the ECM that contributes to chemoresistance and poor prognosis, highlighting its potential as a therapeutic target. Halofuginone (HF), a clinically active derivative of febrifugine, is identified as a COL1A1-targeting natural compound by screening the Encyclopedia of Traditional Chinese Medicine (ETCM). Mechanistically, HF inhibits COL1A1 production via the mTOR-eIF2α-ATF4 axis in CAFs. Notably, HF disrupts collagen deposition and promotes CD8+ T cell infiltration, partially via M2-M1 macrophage polarization to enhance chemosensitivity. Overall, the findings suggest that HF combined with chemotherapy is a promising and effective treatment for ovarian cancer.