Epigenetic Modulators in Cancer Therapy: Mechanisms and Applications

Both genetic alterations and significant epigenetic dysregulation influence cancer development and progression. Epigenetic mechanisms, such as DNA methylation, histone modifications, chromatin remodelling and non-coding RNAs, are essential for regulating gene expression without changing the DNA sequence. Disrupted epigenetic landscapes contribute to tumour initiation, heterogeneity, therapy resistance and immune evasion. Notably, epigenetic alterations are reversible, which makes them promising therapeutic targets. In the past two decades, epigenetic modulators, including DNA methyltransferase inhibitors, histone deacetylase inhibitors, histone methyltransferase inhibitors and bromodomain inhibitors, have shown potential as anticancer agents, with several now approved for clinical use. This chapter presents cancer epigenetics, the main classes of epigenetic modulators, approved and investigational drugs, combination strategies, resistance mechanisms, delivery challenges and future perspectives. Particular attention is given to integrating epigenetic therapy into precision oncology through biomarker-driven strategies and advanced drug-delivery technologies.