MAPKAPK2 and monoclonal gammopathy: Using the gene expression profiling (GEP) database collected from NIH Gene Expression Omnibus GSE2658 as a discovery tool, we found that MK2 expression levels exhibited a dramatic upward trend from normal plasma cells (NP, n = 22), monoclonal gammopathy of undetermined significance cells (MGUS, n = 44), to newly diagnosed myeloma patient plasma cells (n = 351) (Figure 1A).