MDM2 and neuroblastoma: In addition, a study by Giustiniano et al.221has shown that “compound 12” acts as a dual inhibitor of MDM2/p53 and MDM4/p53 complexes and enhances the p53 protein levels in human SHSY‐5Y NB cells. Roscovitine (seliciclib or CYC202) has also been found to inhibit cell viability, activate p53 and p53‐dependent genes (Bax, p21), and inhibit MDM2, N‐Myc, and Akt1 expression.222