Moreover, given the physiological role played by mitochondrial dynamics in the context of immune and endothelial cells[8, 74, 75], and their dysregulation in different cancer types, including PC dyscrasias [76–79], future studies will be aimed at investigating whether Hes- and Nar-dependent Drp1 inhibition could also target aberrant angiogenesis and immune dysfunction acting on other cell populations of the MM bone marrow microenvironment. Here, RRBP1 is linked to cancer.