We have shown UPR-related mRNA loading onto glioma xenograft-derived tumor polyribosomes where GRP94, BiP/GRP78 and GAPDH mRNA distributions in the gradient fractions clearly demonstrate the efficient recruitment of UPR-sensitive transcripts into the heavy-sedimenting polyribosome fractions (Supplemental Figure S5). This evidence concerns the gene GAPDH and central nervous system cancer.