YAP1 and glioblastoma: To address the importance of YAP and HMGB1 to GBM biological behavior further, we analyzed their expression in 51 High Grade Glioma samples by immunohistochemical staining (Fig. 7d) and found a positive correlation between YAP and HMGB1 expression (Fig. 7e, h up), in line with the above results.