CCL18 and glioblastoma: Thereafter, a prognostic index (MRGPI) for GBM samples was constructed based on the regression coefficients derived from multivariate Cox analysis (0.2598, 0.1038, 0.0885, -0.1356, 0.0652 for GPR84, NCF2, HK3, LILRB2, and CCL18), and samples were split into MRGPI-high and -low groups by the median value.