In fact, Liu Q, et al, in their molecular characterization of CD133+ GBM cells, showed that CD133+ GBM cells sorted from neurospheres also expressed CD44 and SOX2, and exhibited enhanced propensity for clonal self-renewal and production of rapidly-growing CD133- progeny, which constitute the major population of cells within the neurosphere niche [35]. Here, CD44 is linked to glioblastoma.