NES and glioblastoma: Against the background that CD133 and Nestin are broadly implicated in the resistance of GBM cells to TMZ treatment [23,24], using the established TMZ-resistant U87MG and D54MG cells, we showed that relative to their parental counterparts, CD133 positivity was enhanced 4.02- and 6.35-fold in the TMZ-resistant U87MG and D54MG cells, respectively (Figure 2B).