Methylation profiling of Waldenstorm's Macroglobulinemia

<p><span>Currently, the role of DNA methylation in the IgM-monoclonal gammopathy disease spectrum remains poorly understood. In the present study, a multi-omics prospective analysis was conducted integrating DNA methylation, RNA-seq and WES data in 34 subjects [23 WM, 6 IgM-MGUS, 5 normal controls]. Analysis was focused on defining differences between IgM-gammopathies (WM/IgM-MGUS) compared to controls, and specifically between WM and IgM-MGUS. Between groups, genome-wide DNA methylation analysis demonstrated a significant number of differentially methylated regions which were annotated according to genomic region. Next, integration of RNA-seq data was performed to identify potentially epigenetically deregulated pathways. We found that pathways involved in cell cycle, metabolism, cytokine/immune signaling, cytoskeleton, tumor microenvironment, and intracellular signaling were differentially activated and potentially epigenetically regulated. Importantly, there was a positive enrichment of CXCR4 signaling pathway along with several interleukin (IL-6, IL-8, IL15) signaling pathways in WM compared to IgM-MGUS. Further assessment of known tumor suppressor genes and oncogenes uncovered differential promoter methylation of several targets with concordant change in gene expression, including <em>CCND1</em> and <em>CD79B</em>. Overall, this report define how aberrant DNA methylation in IgM-gammopathies may play acritical role in the epigenetic control of oncogenesis and key cellular functions. </span></p>