Histone mark remodeling in cancer: an enhancer-centered perspective

Epigenetic deregulation is a defining feature of cancer, and histone modification remodeling plays a central role in reshaping malignant transcriptional programs. Histone marks collectively organize chromatin states that govern enhancer activity, promoter competence, and stability of repressive domains. Across diverse tumor types, redistribution of active and repressive histone modifications reconfigures regulatory landscapes that sustain oncogenic amplification, lineage plasticity, and adaptive resistance. In this review, we examine histone mark remodeling in cancer through an enhancer-centered perspective. We discuss how the gain of H3K27ac-marked enhancers, super-enhancer formation, the erosion of lineage-restrictive regulatory elements, and the redistribution of repressive marks cooperate to reorganize transcriptional circuitry. We further outline the convergent mechanisms driving these alterations, including mutations in chromatin regulators, signal-dependent modulation of epigenetic enzymes, metabolic influences on chromatin state, and changes in three-dimensional genome architecture. The functional consequences of histone mark reprogramming, ranging from cell state transitions and tumor heterogeneity to transcriptional dependency and therapy-associated chromatin adaptation, are considered in the context of tumor evolution. Finally, we highlight emerging single-cell, spatial, and integrative multi-omics approaches that enable systems-level interpretation of chromatin landscapes and identification of context-specific vulnerabilities. By framing histone modification dynamics in terms of enhancer reconfiguration, this review provides a mechanistic and translational perspective on how chromatin remodeling sustains malignant identity and offers opportunities for therapeutic intervention.