Heparan sulfate accumulation and perlecan/HSPG2 up-regulation in tumour tissue predict low relapse-free survival for patients with glioblastoma

Glycosaminoglycans are major components of brain extracellular matrix (ECM), although heparan sulfate (HS) contribution in brain physiology and carcinogenesis remains underinvestigated. This study examined HS content and distribution in glioblastoma multiforme (GBM) tissues in the context of potential molecular mechanisms underlying its deregulation in brain tumours. Totally, 42 tissue samples and paraffin-embedded tissues for 31 patients with different prognosis were investigated. HS expression was demonstrated in 50–55% of the GBM tumours by immunohistochemistry (IHC), while almost no HS content was detected in the surrounding paratumourous brain tissues. Heterogeneous HS distribution in the HS-positive tumours was more related to the necrosis or glandular-like brain zones rather than glioma cells with high or low Ki-67 index. According the Kaplan–Meier curves, HS accumulation in glioma cells was associated with low relapse-free survival (RS) of the GBM patients (p