Taken together, these data indicate that aberrant Wnt activation in malignant plasma cells can be fueled by autocrine and paracrine Wnt ligands and regulates proliferation and drug resistance of MM cells by inducing expression of Wnt target genes, such as CCND1, MYC, and AURKA. As discussed below, several genetic and epigenetic alterations have been identified in MM that reinforce this Wnt pathway activation, either by directly enhancing signaling by Wnt ligands or by facilitating intracellular signal transduction. This evidence concerns the gene CCND1 and Miyoshi myopathy.