As the transcript levels of S100A8 and S100A9 were found to be upregulated significantly in GBM as compared to grade III (Fig. 4A,B), we evaluated the performance of these two transcript to discriminate GBM from control brain and found area-under-curve (AUC) value of 0.72 and 0.74 respectively (p = 0.0001, p < 0.0001, Fig. 5A). Here, S100A9 is linked to glioblastoma.