title: Visualization of mitotic arrest of cell cycle with bioluminescence imaging in living animals.
abstract: OBJECTIVE
  Visualization of the cell cycle in living subjects has long been a big challenge. The present study aimed to noninvasively visualize mitotic arrest of the cell cycle with an optical reporter in living subjects.
  
  
  METHODS
  An N-terminal cyclin B1-luciferase fusion construct (cyclin B-Luc) controlled by the cyclin B promoter, as a mitosis reporter, was generated. HeLa or HCT116 cells stably expressing cyclin B-Luc reporter were used to evaluate its cell cycle-dependent regulation and ubiquitination-mediated degradation. We also evaluated its feasibility to monitor the mitotic arrest caused by Taxotere both in vitro and in vivo.
  
  
  RESULTS
  We showed that the cyclin B-Luc fusion protein was regulated in a cell cycle-dependent manner and accumulated in the mitotic phase (M phase) in cellular assays. The regulation of cyclin B-Luc reporter was mediated by proteasome ubiquitination. In the present study, in vitro imaging showed that antimitotic reagents like Taxotere upregulated the reporter through cell cycle arrest in the M phase. Noninvasive longitudinal bioluminescence imaging further demonstrated an upregulation of the reporter consistent with mitotic arrest induced in tumor xenograft models. Induction of this reporter was also observed with a kinesin spindle protein inhibitor, which causes cell cycle blockage in the M phase.
  
  
  CONCLUSIONS
  Our results demonstrate that the cyclin B-Luc reporter can be used to image whether compounds are capable, in vivo, of causing an M phase arrest and/or altering cyclin B turnover. This reporter can also be potentially used in high-throughput screening efforts aimed at discovering novel molecules that will cause cell cycle arrest at the M phase in cultivated cell lines and animal models.
authors: The Breast Center, Cancer Hospital, Shantou University Medical College, 7 Raoping Road, Shantou, Guangdong, 515031, China. guoj_zhang@yahoo.com
authors: Guo-Jun
authors: GJ
authors: Zhang
authors: Tsing-Bau
authors: TB
authors: Chen
authors: Joseph
authors: J
authors: Davide
authors: Weikang
authors: W
authors: Tao
authors: Amy
authors: A
authors: Vanko
authors: Brett
authors: B
authors: Connolly
authors: David L
authors: DL
authors: Williams
authors: Cyrille
authors: C
authors: Sur
mesh_terms: D000818:Animals; D000970:Antineoplastic Agents / Q000494:pharmacology; D059447:Cell Cycle Checkpoints / Q000187:drug effects; D056744:Cyclin B1 / Q000378:metabolism; D000077143:Docetaxel; D045325:HCT116 Cells; D006367:HeLa Cells; D006657:Histones / Q000378:metabolism; D006801:Humans; D008156:Luciferases / Q000378:metabolism; D049449:Luminescence; D051379:Mice; D008938:Mitosis / Q000187:drug effects; D057054:Molecular Imaging / Q000379:methods*; D015739:Nocodazole / Q000494:pharmacology; D010766:Phosphorylation / Q000187:drug effects; D011401:Promoter Regions, Genetic / Q000235:genetics; D055550:Protein Stability / Q000187:drug effects; D059748:Proteolysis / Q000187:drug effects; D034741:RNA, Small Interfering / Q000378:metabolism; D011993:Recombinant Fusion Proteins / Q000378:metabolism; D040521:Subcutaneous Tissue / Q000187:drug effects; D043823:Taxoids / Q000494:pharmacology; D054875:Ubiquitination / Q000187:drug effects; D023041:Xenograft Model Antitumor Assays
chemical_list: D000970:Antineoplastic Agents; D056744:Cyclin B1; D006657:Histones; D034741:RNA, Small Interfering; D011993:Recombinant Fusion Proteins; D043823:Taxoids; D000077143:Docetaxel; D008156:Luciferases; D015739:Nocodazole