While the majority of the proteins were observed in higher abundances for GBM or GBM subtype samples relative to controls, only eight proteins were observed in higher abundances in controls, including leucine-rich glioma-inactivated protein 1 (LGI1), tenascin R, hyaluronan proteoglycan link protein 1 and 2 (HAPLN1, HAPLN2), laminin subunit beta-2 (LAMB2), and decorin (DCN). Here, DCN is linked to glioblastoma.