Chronic IL-1 exposure attenuates IL-1 response and alters gene expression regulation while maintaining therapeutic sensitivity in BCa cell lines [ChIP-seq]

Interleukin-1 (IL-1) signaling has been widely studied in breast cancer biology; however, the long-term effect of sustained IL-1 exposure on hormone receptor–positive breast cancer cells remain poorly understood. In this study, we investigated how chronic IL-1 exposure influences inflammatory response, hormone dependency, and therapeutic sensitivity in ERα+/PR+ breast cancer models, MCF7 and T47D.

Chronic IL-1 exposure attenuated response to subsequent acute IL-1 treatment, but the chronically exposed cells remained sensitive to serum deprivation, retained dependence on estrogen or progesterone receptor signaling, and responded robustly to endocrine and chemotherapeutic treatments. Extensive changes in basal gene expression and histone modification revealed that chronic IL-1 exposure alters transcriptional reprogramming and chromatin remodeling.