Both REV-ERBα as well as REV-ERBβ have significant contributions in circadian rhythms, inflammation, tumorigenesis, and glucose as well as lipid metabolism, which play a role as the components associating the CC with the cellular metabolism. An elevated level of NR1D2 (REV-ERBβ) expression was found to correlate positively with glioma grades. Compared to healthy noncancerous astrocytes, increased levels of NR1D2 were found in glioblastoma multiforme cells. This evidence concerns the gene NR1D1 and central nervous system cancer.