title: The cell cycle: accelerators, brakes, and checkpoints.
abstract: PROLIFERATIVE CUES TRIGGER a complex series of molecular signaling events in cells. Early in the cell cycle, cells are faced with an important decision that affects their fate. They either initiate a round of replication or they withdraw from cell division. Passage through the restriction point, or "point of no return," marks cellular commitment to a new round of division. Genetic mutations that predispose individuals to tumorigenesis often affect pathways that influence cellular proliferation. Many of the mutated genes give rise to molecules that are no longer able to appropriately regulate the mammalian cell cycle; the end result is neoplasia. In this review, the critical elements that permit cell cycle progression and the positive and negative regulators that affect the process are reviewed.
authors.affiliation: Division of Neurosurgery and the Arthur and Sonia Labatt Brain Tumor Research Centre, The Hospital for Sick Children, Toronto, Ontario, Canada.
authors.forename: Stacey M
authors.initials: SM
authors.lastname: Ivanchuk
authors.forename: James T
authors.initials: JT
authors.lastname: Rutka
mesh_terms: D001932:Brain Neoplasms / Q000235:genetics*; D002453:Cell Cycle / Q000235:genetics*; D002455:Cell Division / Q000235:genetics*; D002471:Cell Transformation, Neoplastic / Q000235:genetics*; D018844:Cyclin-Dependent Kinases / Q000235:genetics; D016213:Cyclins / Q000235:genetics; D004252:DNA Mutational Analysis; D015972:Gene Expression Regulation, Neoplastic / Q000502:physiology; D005809:Genes, Regulator / Q000235:genetics*; D016147:Genes, Tumor Suppressor / Q000502:physiology; D006801:Humans; D016160:Retinoblastoma Protein / Q000235:genetics; D015398:Signal Transduction / Q000235:genetics; D016159:Tumor Suppressor Protein p53 / Q000235:genetics
chemical_list: D016213:Cyclins; D016160:Retinoblastoma Protein; D016159:Tumor Suppressor Protein p53; D018844:Cyclin-Dependent Kinases