Figure 4.

Therapeutic doses of temozolomide can deplete the pre-existing GSC pool. FACS analysis of the GFP-tagged (GFP⁺) DN (CD133⁻CD15⁻) non-GSC and DP (CD133⁺CD15⁺) GSC populations. Cell viability was assessed by 7-AAD staining. Although DN cells are killed by TMZ treatment, there is no preferential death of the DN non-GSC population upon long-term TMZ therapy (either on day 4 (∼12%) or 8 (∼7%)). DP GFP⁺ cells seem to be more vulnerable to TMZ therapy (∼33% of 7-AAD⁺ cells 8 days post-initial therapy). Error bars denote S.E.M. P: ns (P>0.05), *P<0.05, **P<0.01, ***P<0.001, one-way analysis of variance