CXCL9 and glioblastoma: Using the IVW method, we discovered a possible correlation between an increased risk of glioblastoma and elevated levels of C-X-C motif chemokine 9 (CXCL9) and Interleukin-33 (IL-33) (OR, 1.03; 95% CI: 1.01, 1.06; p = 0.021; OR, 1.03; 95% CI: 1.03, 1.06; p = 0.030) (Figure 3; Supplementary Table S7).