PTBP1 and glioblastoma: In a previous study of data from The Cancer Genome Atlas (TCGA), we found that 3′UTR shortening also occurs in glioblastoma (GBM), and we have associated this APA pattern with the increased expression of the polypyrimidine tract binding protein 1 (PTBP1), which has much higher expression in GBM compared to normal tissue (Gruber et al., 2018).