BIRC5 and central nervous system cancer: To unveil the molecular mechanism behind the synergistic combination between TMZ and miR-138 overexpression, TCGA database was mined for the correlation of expressions between miR-138 and BIRC5. Compared to the RNA expression in normal tissues (53.24 ± 104.6, n = 10), mRNA expression of BIRC5 was up-regulated in most types of glioma patients: classical (120.7 ± 64.42, n = 52); mesenchymal (130.0 ± 110.6, n = 58); neural (186.7 ± 154.8, n = 30); and proneural (289.6 ± 228.4, n = 56) (Figure 3A).