Taken together, results of neutralization assay and comparison of double immunostaining of CXCR1 and CD34 in GBM tissues strongly suggest that IL-8-CXCR1 axis is not only involved in neovascularization but is also driving VM structure formation which has been considered an independent adverse prognostic factor in GBM [22]. This evidence concerns the gene CD34 and glioblastoma.