MYCN and neuroblastoma: We used three MYCN non-amplified NB cell lines, CHLA-255, SK-N-AS, and SH-SY5Y; three MYCN amplified NB cell lines, NGP, LAN-5, and IMR-32; three non-cancerous fibroblast cell lines, COS-7, NIH-3T3, and WI-38, for cytotoxicity studies (Figure 2).