However, a negative CHIP regulator known as CSN6 has been identified in GBM, a constitutive photomorphogenesis 9 (COP9) signalosome (CSN) subunit with oncogenic properties [90], whose expression levels are significantly higher in GBM tumors in contrast to normal brain tissues, as well as in glioma cell lines. This evidence concerns the gene COPS6 and glioblastoma.