Epigenetic Mechanisms of Breast and Ovarian Cancer Development: Interplay Between DNA Methylation/Demethylation Enzymes, MicroRNAs, and Long Non-Coding RNAs.

Structural and functional disruptions of the epigenome are hallmarks of breast and ovarian carcinogenesis. This review dissects the reciprocal regulatory networks co-operated by DNA methyltransferases (DNMTs), ten-eleven translocation enzymes (TETs), and key non-coding RNAs (microRNAs and lncRNAs). We map the precise molecular mechanisms through which these epigenetic modulators alter chromatin accessibility, drive transcriptional reprogramming, and promote phenotypic plasticity in hormone-dependent malignancies. By systematically contrasting the distinct yet overlapping epigenetic profiles of breast and ovarian tumors, we elucidate how these aberrations dictate clinical outcomes. This comprehensive synthesis offers critical insights into the dual utility of these epigenetic elements as dual-purpose diagnostic biomarkers and druggable therapeutic targets, laying the groundwork for next-generation targeted epigenetical therapies.