**4. Impairment of Akt activation and cell proliferation in NB by Akt inhibitor, MK2006**

MK2206 selectively inhibits AKT and has potency against Akt1 and Akt2 isoforms than Akt3. In pediatric solid tumors, MK2206 is effective in vitro and in vivo [34, 35]. In clinical trials, stable disease was observed in different kinds of cancers [36, 37]. Our results also suggested that MK2206 (2.5 μM) completely inhibited Akt phosphorylation and cell proliferation in NB cell lines [10]. Furthermore, MK2206 also impaired the cell proliferation induced by exogenous IGF and insulin in NB cell lines [10].
