For instance, miR-15b induced cell cycle arrest at G0/G1 phase by targeting cyclin E in glioma cells [23]; miR-16 induced G1 arrest partially by targeting cyclin D1 [24]; miR-122a can modulate cyclin G1 expression in human hepatocellular carcinoma-derived cell lines [25]. This evidence concerns the gene CCNG1 and central nervous system cancer.