ATM and neuroblastoma: MYCN expression was undetectable in GI-ME-Nkd-3650, GI-ME-Nkd-1463 and GI-ME-Nkd-LacZ cells by Western Blotting and real-time quantitative PCR (Figure 11E), thus further corroborating the conclusion that the tumor promoting effect of ATM silencing in the NB cell background does not require MYCN.