PLK1 and neuroblastoma: Therefore, in the present study, we have investigated the therapeutic efficacy of small molecule inhibitors 13-197, NF-kB and mTOR pathways dual inhibitor; vismodegib, hedgehog pathway inhibitor and BI2536, PLK1 inhibitor either alone or in combination with topotecan against non-MYCN and MYCN-amplified neuroblastoma cell lines.