In order to investigate, whether CXCR4 expression was enhanced at the neuroblastoma cell surface in response to exogenously added BK explaining the increased responsiveness of these cells to SDF-1 in the chemotaxis assay, flow cytometry analysis was undertaken with CHP-134, IMR-32, and CHP-100 cell lines. This evidence concerns the gene CXCR4 and neuroblastoma.