The 14 pathways belonging to “cell cycle” are cell cycle control of chromosomal replication, role of BRCA1 in DNA damage response, hereditary breast cancer signaling, mitotic roles of polo-like kinase, role of CHK proteins in cell cycle checkpoint control, aryl hydrocarbon receptor signaling, GADD45 signaling, estrogen-mediated S-phase entry, ATM signaling, cell cycle: G1/S checkpoint regulation, cell cycle: G2/M DNA damage checkpoint regulation, glioma signaling, small-cell lung cancer signaling, and ovarian cancer signaling. The gene discussed is AHR; the disease is central nervous system cancer.