DERL2 and glioma: We identified ER stress and UPR as key aging-related mechanism behind tumor aggressiveness in gliomas, and developed a six gene “ER Stress and UPR-driven Aging-related Tumor Aggressiveness in Glioma” (ESURATAG) gene signature, comprising DERL2, RPN2, SEC13, SEC61A1, SEC61B, and STT3A.