Jul 2026· Chemical Research in Toxicology· Vol 39, pp. 1483-1502· 0 citations· 189 references
BiologyMedicine
TL;DR
The mechanisms and roles of DNA methylation in epigenetic regulation are examined, the current landscape of DNA methylation modulators are evaluated, from traditional DNMT inhibitors to cutting-edge CRISPR-dCas9 fusion systems and protein-protein interaction disruptors, and their clinical relevance are evaluated.
Abstract
DNA methylation can function as a toxic alkylation reaction exploited by chemotherapeutic agents to induce cancer cell death. However, finely tuned DNA methylation plays a fundamental role in cellular physiology, particularly in the epigenetic regulation of gene expression. Once thought to act solely as a repressor of gene transcription, its functional role has since been elucidated as genomic locus-specific and deeply connected with other epigenetic factors. Following the clinical approval of DNA methyltransferase inhibitors, such as Azacitidine and Decitabine, for the treatment of hematological malignancies, considerable efforts have been devoted to developing pharmacological tools that modulate epigenetic DNA methylation. However, the lack of gene selectivity in these agents limits their therapeutic efficacy and increases off-target toxicity. Moreover, the non-gene-selective nature of current DNA methylation-targeting molecules fails to meet the standards required to discern the nuanced roles of DNA methylation across diverse pathophysiological contexts and genomic loci, particularly in an era where next-generation sequencing and omics technologies enable high-resolution epigenetic analyses. In this review, we examine the mechanisms and roles of DNA methylation in epigenetic regulation, evaluate the current landscape of DNA methylation modulators, from traditional DNMT inhibitors to cutting-edge CRISPR-dCas9 fusion systems and protein-protein interaction disruptors, and discuss their clinical relevance. Finally, we emphasize the need for precise, locus-specific tools to advance both cancer research and therapeutic strategies.
Although cells within an organism share nearly identical genomes, their transcriptional programs differ markedly due to reversible chemical modifications known as epigenetic marks. These marks, including DNA methylation and histone modifications, regulate gene expression without altering DNA sequence and play a central role in development and disease. While epigenetic drugs such as DNA methyltransferase inhibitors have shown clinical benefit, their genome-wide activity often results in off-target toxicity limiting broader therapeutic applications. This has driven the development of locus-specific epigenetic editing strategies. Programmable epigenetic modifiers (PEMs) combine customizable DNA-binding platforms, such as CRISPR-dCas systems, transcription activator-like effectors (TALEs), or zinc fingers, with epigenetic effector domains to precisely install or remove regulatory marks at defined genomic loci. Because effective editing depends on the pre-existing epigenetic landscape, detection and characterization of target-site epigenetic states is a prerequisite for rational editor design, increasingly aided by machine-learning models that predict editing outcomes. In this review, we summarize current technologies for epigenetic mark detection and discuss the transition from global pharmacological approaches to programmable, modular editing systems that enable spatial and temporal control of gene regulation. We further address heritability and delivery constraints. Reversible, site-specific epigenetic editing represents a promising therapeutic paradigm for cancer, genetic disorders, and regenerative medicine.
This review presents an in-depth analysis of the most recent advances in small-molecule epigenetic modulators, focusing on their mechanisms of action, therapeutic applications, and the challenges impeding their clinical development, with the aim of informing the rational design and optimization of next-generation epigenetic treatment strategies for cancer.
Peng Jin, Yi Wang, Na Zhao et al.· Biochimica et biophysica act...· 0 citations
As the field of anticancer drug development is constantly changing, combining synthetic lethality with epigenetic modifiers opens up new possibilities for targets that fall outside the traditional drug target range. Enzymes involved in DNA methylation and histone modification are examples of epigenetic modifiers that promote gene expression without altering the DNA sequence of the gene. These mechanisms play a key role in carcinogenesis when they are altered, as they downregulate tumor suppressor genes and overexpress oncogenic pathways. Synthetic lethality is a phenomenon in which simultaneous mutations or perturbations of two genes result in cell death, but alterations to one gene alone do not cause cell death. It was first observed in genetic research conducted on model organisms, such as fruit flies and fungi. The most well-known example of this idea from the perspective of cancer treatment is PARP inhibitors, which are effective in tumors with BRCA1/2 mutations, where further failure of DNA repair results in cell sensitization. Building on the concept of synthetic lethality, current research focuses on exploiting epigenetic flaws that are common in cancer cells. For example, when chromatin remodelers or methyltransferases cease to function, malignant cells undergo genetic rewiring, rendering them vulnerable to treatment. Recent research has produced some striking examples of synthetic-lethal drug interactions and biomarkers used in metagenomics for personalized medicine by targeting the secondary pathways used by cancer cells as a result of primary loss-of-function mutations, which selectively kill cancer cells while sparing healthy cells. The discovery of actionable epigenetic dependencies and overcoming tumor heterogeneity remain the largest challenges in translating these fascinating scientific discoveries to the clinic. The convergence of epigenetic modulators with synthetic-lethality-based therapeutic architectures is poised to define a transformative paradigm in precision oncology. By orchestrating multilayered perturbations across chromatin-regulatory networks, DNA damage-response pathways, and context-specific vulnerability nodes, this integrative strategy surpasses the limitations of conventional target-centric pharmacology and enables mechanistically rational, synergistic antitumor interventions.
Venkatesh Kamath, Vasudev Pai, Bhavana Bhat et al.· Current Topics in Medicinal...· 0 citations
Cell-specific epigenetic editing holds very high therapeutic value for atherosclerosis, cardiomyopathy, and fibrosis, provided that delivery, specificity, and safety challenges are also addressed.
Majed Alsulami, Mahmood Rasool, Ahmed Masoud et al.· The Cardiology· 0 citations
Results indicate that targeted reactivation of BFL-1 and SQOR increases cell-death susceptibility in liver cancer cells, providing proof-of-concept for locus-specific epigenetic therapy in liver cancer.
Wonjin Woo, Seol-Hwa Jeong, Ayoung Hwang et al.· Molecules and Cells· 0 citations