In line with clinical observations of CXCL2 concentration directly correlating with worse overall survival [29,32,33], we could find a correlation between spheroid outgrowth and CXCL2 concentrations in the supernatants, but only in the dexamethasone-treated group, which might even reflect a disadvantageous effect of the ubiquitously applied symptomatic dexamethasone treatment of GBM in the clinical practice. Here, CXCL2 is linked to glioblastoma.