MYCN and neuroblastoma: Retinoid therapy, inducing neuroblastoma cell differentiation and growth inhibition, was shown to induce miR-34a levels.35 Alternatively to TAp73-mediated induction of miR-34a in retinoid-induced neuroblastoma differentiation,75 it is plausible that retinoid-induced downregulation of N-Myc represents another mechanism of miR-34a control.100 Gene expression analysis on a panel of breast tumor samples identified a co-regulation between miR-34a and targets of Myc-associated zinc finger protein MAZ,101 further corroborating the implication of miR-34a in Myc signaling.