SOX2 and central nervous system cancer: In patients with SOX2 high expression in primary glioma, 13 cases (54.2%) changed to SOX2 low expression after recurrence, the prognosis of these patients seemed worse than patients with stable SOX2 expression (PFS: 10.4 vs. 14.9 months, p = 0.036; OS: 18.5 vs 32.8 months, p = 0.249) (Fig. 4c, d).