Similarly, as shown in Figure 1C and Tables 1, 2, the ROC curve analysis also indicated that the expression level of COL4A1, COL4A2 and COL4A6 has a higher correlation with GBM (AUC = 0.838, 0.835 and 0.854) and LGG (AUC = 0.790, 0.786 and 0.843) than that of COL4A3, COL4A4 and COL4A5 (AUC = 0.639, 0.570 and 0.592 in GBM; 0.604, 0.647 and 0.610 in LGG). This evidence concerns the gene COL4A2 and glioblastoma.