PEA15 and glioblastoma: Our elimination analysis of GREPDR5 genes also identified genes such as phosphoprotein-enriched-in-astrocytes 15 (PEA15), which has been previously associated with insensitivity to Apo2L/TRAIL in glioblastoma by modulation of the DISC to inhibit caspase-8 cleavage [25], but is otherwise not well described as a negative regulator of DR5.