Epimutations and Their Effect on Chromatin Organization: Exciting Avenues for Cancer Treatment

SIMPLE SUMMARY: Epigenetic modifications, such as DNA methylation and histone modification, have been found to alter in various cancer types. These modifications lead to uncontrolled cellular proliferation, evasion from apoptosis, and metastasis. Deregulation in epigenetic pathways often results in the suppression of tumor-suppression genes or activation of oncogenes in cancers. Inhibitors targeting deregulated enzymes can restore balance by reactivating altered pathways. Several inhibitors that target DNA methylation and histone modifications are currently being used in clinics and have shown promising results in cancer therapeutics. ABSTRACT: The three-dimensional architecture of genomes is complex. It is organized as fibers, loops, and domains that form high-order structures. By using different chromosome conformation techniques, the complex relationship between transcription and genome organization in the three-dimensional organization of genomes has been deciphered. Epigenetic changes, such as DNA methylation and histone modification, are the hallmark of cancers. Tumor initiation, progression, and metastasis are linked to these epigenetic modifications. Epigenetic inhibitors can reverse these altered modifications. A number of epigenetic inhibitors have been approved by FDA that target DNA methylation and histone modification. This review discusses the techniques involved in studying the three-dimensional organization of genomes, DNA methylation and histone modification, epigenetic deregulation in cancer, and epigenetic therapies targeting the tumor.