NODAL and glioblastoma: Therefore, to elucidate whether the vesicle-like particles observed in stem and differentiated GBM cells correspond to the same subcellular compartments or not or even whether they may change according to the differentiation status of GBM cells, we performed immuno co-localization of Nodal and different endosomal proteins in OB1 and differentiated OB1 cells (Figs. 3, 4).