Epigenetic Rewiring of Enhancer–Promoter Interactions in Cancer: Mechanisms and Therapeutic Implications

Cancer is increasingly recognized as a disease of transcriptional dysregulation in which genetic alterations and epigenetic remodeling cooperate to reprogram gene regulatory networks that govern cellular identity, proliferation, differentiation, and therapeutic response. Enhancer–promoter interactions are an important component of the regulatory systems that establish cell-type-specific gene expression and lineage identity. Cancer cells exploit the intrinsic plasticity of the epigenome to remodel enhancer landscapes, redistribute lineage-specific transcription factors (TFs), alter chromatin accessibility, reorganize three-dimensional (3D) genome architecture, and establish novel enhancer–promoter interactions that sustain oncogenic transcriptional programs. In this review, we discuss how enhancer–promoter communication is established and maintained within the 3D genome and examine the molecular mechanisms and drivers underlying epigenetic rewiring of enhancer–promoter interactions in cancer. We also highlight how the alterations of these epigenetic processes contribute to cancer initiation, progression, metastasis, and therapeutic resistance. Finally, we discuss epigenetic therapeutic strategies and emerging genomic technologies that exploit aberrant enhancer–promoter interactions to advance precision oncology.