As illustrated, the mRNA expression levels of CXCL14 (P value < 0.001), CXCL9 (P value < 0.001), CXCL10 (P value < 0.001), CXCL11 (P value < 0.001), CXCL13 (P value < 0.001), CXCL3 (P value < 0.001), CXCL1 (P value < 0.001), CXCL6 (P value < 0.001) in the GBM group were significantly higher than that in the lower-grade gliomas (LGG) group, while CXCL12 (P value < 0.01) had a higher expression in the LGG group (Figure 1A) according to the training cohort. This evidence concerns the gene CXCL12 and central nervous system cancer.