Epigenetic Alterations in Colitis-Associated Colorectal Cancer.

Colitis-associated colorectal cancer (CAC) represents a distinct subtype of colorectal malignancy that arises in the setting of chronic inflammatory bowel disease (IBD). Unlike sporadic colorectal cancer, CAC develops through inflammation-driven molecular pathways, in which epigenetic alterations play a pivotal role in tumor initiation and progression. This review highlights the major epigenetic mechanisms implicated in CAC, including DNA methylation, histone modifications, and microRNA (miRNA) dysregulation. Aberrant DNA methylation patterns, such as promoter hypermethylation of tumor suppressor genes and global hypomethylation, contribute to genomic instability and altered gene expression. In parallel, inflammation-induced changes in histone configuration modulate chromatin accessibility and transcriptional activity of key oncogenic and tumor-suppressive pathways. Furthermore, deregulated miRNAs influence multiple aspects of CAC pathogenesis by targeting genes involved in inflammation and tumor progression. Understanding these epigenetic processes provides valuable insights into the development of colorectal malignancy and identifies potential biomarkers for early detection and intervention in colitis-associated colorectal cancer.