GRP and brain neoplasm: Brain tumor tissue studied by Western blot and immunohistochemistry (IHC) showed a marked increase in the constitutive expression of Hsp27, Hsp90, GRP (glucose regulated proteins) 78 and 75, and Hsc70 (or Hsp70) and the co-chaperone HspBP1 (Hsp70 Binding Protein 1) [112,114,115] (Table 1).