COL6A1 and glioblastoma: Combination survival analysis revealed that COL6A1‐high and ITGA5‐high GBM patients had bad prognosis in comparison with COL6A1‐low and ITGA5‐low GBM patients (TCGA GBM: hazard ratio = 1.880, 95% confidence interval = 1.200–2.946, p = 0.0022; Rembrandt GBM: hazard ratio = 1.941, 95% confidence interval = 1.330–2.833, p = 0.0001) (Figure 7I,J).