GLUL and glioblastoma: As to the studies based on glioblastoma cohorts, younger age,14,34 certain tumor locations,13,14 expression of p5334 and glutamine synthetase,10,15 higher preoperative KPS score,14 smaller volume of tumor, intratumoral necrosis and peri-tumoral edema,10,11 and statin medication (inversely)11 were reported to be associated with SAO.