We found that low expression of COX-2 was significantly correlated with extended progression-free survival (PFS) of GBM patients at different stratifications (Figure 8; 25% quartile vs. 75% quartile: 381.7 ± 443.2 vs. 286.1 ± 365.7 days; 50% quartile: 342.3 ± 384.3 vs. 277.2 ± 390.1 days) after adjusting for age and gender. The gene discussed is PTGS2; the disease is glioblastoma.