IGFBP3 and glioblastoma: The proposed hypoxic protein signature included insulin-like growth factor-binding protein 3 (IGFBP3), coagulation factor III, carbonic anhydrase 9 (CA9), glucose transporter 1 (SLC2A1), and progesterone receptor membrane component 1 (PGRMC1) mRNAs, which have previously demonstrated an involvement in GBM hypoxia and progression.