Figure 4.

Model of SDF-1-mediated signal transduction for targeting of stem cells toward brain tumor. Brain tumors release SDF-1 gradient into the tumor microenvironment. Binding SDF-1 to its receptor expressed in stem cells triggers the signal transduction pathways that lead to cytoskeletons reorganization, which drives stem cell migration toward brain tumor microenvironment. CXCR-4: chemokine (C-X-C motif) receptor 4, a.k.a., SDF-1 receptor or CD184; SDF-1: stromal cell-derived factor-1 (chemokine), a.k.a., CXCL12 (see [37]).