a, Correlation between LGALS1 and CD44 levels in patient samples of primary and recurrent GBM (UCSF cohort; n = 10 patients per group). r from Pearson’s correlation. b, Survival probability versus expression level of PDPN (n = 214 GBM patients (TCGA)). P value calculated using two-sided logrank test. c, PDPN expression in proneural (Pro; n = 57 patients) and mesenchymal (Mes; n = 58 patients) GBM (TCGA). Mean ± s.e.m.; *P = 1.78 × 10–14 by two-sided Mann–Whitney U-test. d, CD44 and PDPN expression was analysed in proneural and mesenchymal cultures to distinguish a DP population (n = 3 independent sorting experiments). e, RNA from these populations was analysed. Mean ± s.e.m. (n = 4, 5, 3 and 6 independent experiments for SOX2, HES1, TNC and LGALS1, respectively). *P = 0.12, 0.06, 0.12 and 0.03, respectively, by two-sided paired t-test. f, CD44:PDPN DP and CD44 SP cells were treated with temozolomide (TMZ) for 72 h (n = 4 per dose per group). Mean ± s.e.m.; **P = 0.0001 and ***P = 1.31 × 10–18 by two-way ANOVA and Bonferroni post-test. g, The DP population was quantified from n = 2 for proneural and n = 3 independent experiments for others. Mean ± s.e.m.; F (3,7) = 149.0252, ***P = 1.05 × 10–6 by one-way ANOVA and Bonferroni post-test. h, Mesenchymal Scr, shGal and shFAK cells were treated with 50% growth inhibitory (GI50) dose of temozolomide at 7.5 μM for 72 h (n = 3 independent experiments per dose per group). *P = 0.01 and 0.04 for shGal and shFAK, respectively, verus Scr by one-way ANOVA. i, Secondary sphere colony formation was performed using primary neural stem cells (n = 4 independent experiments). *P = 0.03 by two-sided Mann–Whitney U-test. RNA from these spheres was assayed for HES1 expression (n = 3 independent experiments). Mean ± s.e.m.; **P = 0.002 by two-sided paired t-test. j, RNA from Scr, shGal and shFAK cells was analysed. Mean ± s.e.m. (n = 5, 4 and 3 independent experiments for SOX2, POU3F2 and HES1, respectively). P = *0.04, 0.2 and *0.03 by one-way ANOVA. k, Limiting dilution assays were performed using mesenchymal Scr and shGal-1 cells (n = 3 independent experiments). Mean ± s.e.m.; P = *0.02, *0.04 and **0.008 for 1,000, 100 and 10 cells per well, respectively, by two-sided paired t-test. l,m, In vivo limiting dilution studies using 100 and 1,000 cells per mouse (n = 5 mice per group). Tumour-bearing mice shown at study endpoint (l) and quantified for indicated dilutions (m).