Relationship Between Noncoding RNA Dysregulation and Epigenetic Mechanisms in Cancer

Epigenetic alterations, including aberrant DNA methylation and histone modification, play key roles in the dysregulation of tumor-related genes, thereby affecting numerous cellular processes, including cell proliferation, cell adhesion, apoptosis, and metastasis. In recent years, studies have demonstrated that short and long noncoding RNAs (ncRNAs) are key players in the initiation and progression of cancer, and epigenetic mechanisms are deeply involved in their dysregulation. Indeed, the growing list of microRNA (miRNA) genes aberrantly methylated in cancer suggests that a large number of miRNAs act as tumor suppressors or oncogenes. In addition, emerging evidence suggests that dysregulation of long ncRNAs (lncRNAs) plays critical roles in tumorigenesis. And because ncRNAs are involved in regulating gene expression through interaction with epigenetic modifiers, their dysregulation appears causally related to epigenetic alterations in cancer. Dissection of the interrelationships between ncRNAs and epigenetic alterations has the potential to reveal novel approaches to the diagnosis and treatment of cancer.