MYCN and neuroblastoma: To further understand the role of MELK in NB, we first examined the overall level of MELK protein in a panel of six NB cell lines consisting of three MYCN-amplified, IMR-32, NB-19 and NGP, and three MYCN-non-amplified, CHLA-255, SH-SY5Y and SK-N-AS cell lines (Figure 3A).