SOX21 and glioblastoma: The heatmap of the irlncRNAs signature in the training (Figure 2H; Table S13), testing (Figure S3B; Table S14), and total sets (Figure S1B) revealed that GBM with high prognostic scores expressed high-risk irlncRNAs (H19, AL162231.2, AC002456.1), whereas GBM with low prognostic scores expressed protective irlncRNAs (ST3GAL6-AS1, SOX21-AS1, AC006213.5).