While Inoue et al claimed that PTGS2 inhibitors enhanced the effects of radiotherapy on prostate cancer and largely prevented the stimulation of F98 cell infiltration into the brain,24, 25 Yang et al26 found that celecoxib, a PTGS2‐selective inhibitor, sensitized the responsiveness of these medulloblastoma cells to IR exposure in vitro. Here, PTGS2 is linked to prostate carcinoma.