RAD51 and glioblastoma: The HR pathway is an attractive target as it is linked to increased genetic variation and loss of heterozygosity (LOH).12, 27 Multiple HR checkpoints have been proposed as potential therapeutic targets for GBM.28, 29, 30, 31 Although the prognostic value of RAD51 expression in GBM is unresolved,29, 32, 33 RAD51 is consistently elevated in GBM compared with normal brain.33 Reducing RAD51 expression radiosensitizes GBM cells,29 but may have a limited therapeutic index because of the potentially toxic effects on non-neoplastic cells.