As for the relationship between CD133+ and CD15+ cells, Son et al. reported that most CD133+ tumor cells freshly isolated from glioma specimens were CD15+ [6], but a less overlap between CD133+ and CD15+ subsets was observed in GBM1 and LN229 cells (Additional file 1: Figures S6 and S7). The gene discussed is PROM1; the disease is neoplasm.