HPSE and glioblastoma: The difference in HPSE expression in individual GBM tumours stratifies them into two sub-groups (HPSE-positive and HPSE-negative) with potentially different clinical characteristics, which might correspond to Kundu’s data on the correlation of a high level of heparanase expression with low survival of patients with glioblastoma [31], supplementing them with new data on the high intratumoural heterogeneity of HPSE distribution in glioblastoma tissues.