Aberrant Epigenetic Gene Regulation in Lymphoid Malignancies

In lymphoid malignancies, aberrant epigenetic mechanisms such as DNA methylation and histone modifications influence chromatin architecture and can result in altered gene expression. These alterations commonly affect genes that play important roles in the cell cycle, apoptosis, and DNA repair in non-Hodgkin lymphoma (NHL). The ability to identify epigenetic modifications to these important genes has increased exponentially due to advances in technology. As a result, there are well-defined, gene-specific epigenetic aberrations associated with NHL comprising follicular lymphoma (FL), mantle cell lymphoma (MCL), chronic lymphocytic leukemia (CLL), and diffuse large B-cell lymphoma (DLBCL). The identification of these genes is important because they may be used as biomarkers for prognosis, diagnosis and in developing improved treatment strategies. Also important, in the control of gene expression, is the packaging of DNA within the nucleus of a cell. This packaging can be distorted by epigenetic alterations and may alter the accessibility of certain regions of the genome in cancer cells. This review discusses the impact of known epigenetic aberration on the regulation of gene expression in NHL and provides insight into the spatial conformation of the genome (DNA packaging) in acute lymphoblastic leukemia.