XBP1 and glioblastoma: For additional validation, we performed Western blot analyses on 3 patient GBM samples (compared to normal human frontal cortex) for fatty acid synthase (since lipid biosynthesis is a downstream activity of the UPR), for ER chaperones GRP170/ORP150, GRP94, GRP78, ERp72, and calreticulin, as well as the activated (spliced) and quiescent (unspliced) form of XBP-1.