To determine the effect of CCL2 on neuroblastoma cell proliferation, four firefly-luciferase labeled neuroblastoma cell lines (SH-SY5Y-Fluc, CHLA-255-Fluc, NGP-Fluc, SMS-KCNR-Fluc) were cultured in increasing concentrations of CCL2. The gene discussed is CCL2; the disease is neuroblastoma.