Similar to miR-K12-11, the other viral miR-155 ortholog encoded by KSHV (Liu et al., 2012), miR-M4-5p has been demonstrated to target TGF-β signaling pathway by downregulating the LTBP1 expression to suppress the maturation and secretion of TGF-β1, as well as to activate the expression of host oncoprotein c-MYC (Chi et al., 2015), triggering the development of MD tumors. The gene discussed is TGFB1; the disease is Menkes disease.