CXCL12 and glioblastoma: Figure 3c indicates that GBM spheroid formation is affected by Alisertib (48 h, 10 nM) (U87MG: 2.0 fold, GBM1: 1.5 fold) and increased in response to CXCL12 stimulation (16 h, 100 nM) (U87MG: 1.7 fold, GBM1: 1.2 fold).