As it was reported for its binding partner BMAL1, TCGA database analysis revealed that the Clock gene, located at 4q12 chromosomal region, is amplified in ~5% of GBM patients [216,220], and high-grade gliomas exhibited an increased expression of CLOCK compared to low-grade glioma or non-tumor cells [211,223,224,225]. Here, CLOCK is linked to glioblastoma.