Recently, the secretion of periostin from glioma stem cells (GSCs) has also been demonstrated to support macrophage recruitment and transition into an M2 phenotype, and the deletion of POSTN in GSCs resulted in a dramatic reduction of GAM density and GBM growth, as well as an increased survival rate of mice bearing GSC-derived xenografts (43). The gene discussed is POSTN; the disease is glioblastoma.