Opposing Outcomes of Short- and Long-Term Epigenetic Therapy in Breast Cancer: Implications for Chemotherapy Response

Targeting epigenetic modifications has gained considerable attention as a therapeutic approach in cancer, with several epigenetic drugs (Epidrugs) already earned the Food and Drug Administration (FDA) approval. Despite this progress, their clinical application in solid tumors including breast cancer remains limited, emphasizing the importance of optimizing treatment strategies with respect to duration and scheduling. In this study, we evaluated the impact of short- (2 days) and long-term (3 months) exposure to Epidrugs on gene expression and chemosensitivity in breast cancer cells using Tazemetostat (TAZ), an EZH2 inhibitor, alongside the HDAC inhibitor vorinostat and the DNA demethylating agent decitabine.