Interestingly, in a study comparing the gene expression in cancer cells from MM patients with cancer cells from two related B cell cancers, chronic lymphocytic leukemia and Waldenström’s macroglobulinemia, phosphoglycerate dehydrogenase (PHGDH) was ranked number 15 on the list of upregulated genes in MM, indicating that this enzyme is of particular significance in MM [8]. Here, PHGDH is linked to Waldenstrom macroglobulinemia.