@article {5181,
	title = {G(2) DNA damage checkpoint inhibition and antimitotic activity of 13-hydroxy-15-oxozoapatlin},
	journal = {Journal of Biological Chemistry},
	volume = {276},
	number = {51},
	year = {2001},
	note = {ISI Document Delivery No.: 505QLTimes Cited: 24Cited Reference Count: 51},
	month = {Dec},
	pages = {48231-48236},
	type = {Article},
	abstract = {Checkpoints activated in response to DNA damage cause arrest in the G(1) and G(2) phases of the cell cycle. Inhibitors of the G(2) checkpoint may be used as tools to study this response and also to increase the effectiveness of DNA-damaging therapies against cancers lacking p53 function. Using a cell-based assay for G(2) check. point inhibitors, we have screened extracts from the NCI National Institutes of Health Natural Products Repository and have identified 13-hydroxy-15-oxozoapatlin (OZ) from the African tree Parinari curatellifolia. Flow cytometry with a mitosis-specific antibody showed that checkpoint inhibition by OZ was maximal at 10 muM, which released 20\% of irradiated MCF-7 cells expressing defective p53 and 30\% of irradiated HCT116p53(-/-) cells from G(2) arrest. OZ additively increased the response to the checkpoint inhibitors isogranulatimide and debromohymenialdisine, but it did not augment the effects of UCN-01 or caffeine. Unlike other checkpoint inhibitors, OZ did not inhibit ataxia-telangiectasia mutated (ATM), ATM and Rad3-related (ATR), Chk1, Chk2, Plk1, or Ser/Thr protein phosphatases in vitro. Treatment with OZ also caused G(2)-arrested and cycling cells to arrest in mitosis in a state resembling prometaphase. In these cells, the chromosomes were condensed and scattered over disordered mitotic spindles. The results demonstrate that OZ is both a G(2) checkpoint inhibitor and an antimitotic agent.},
	keywords = {ARREST, BHK CELLS, CAFFEINE, CELL-CYCLE CHECKPOINTS, CHROMOSOME ALIGNMENT, G2, P34(CDC2) KINASE, PROTEIN-KINASE, RADIOSENSITIZING AGENT, TYROSINE KINASE, UCN-01},
	isbn = {0021-9258},
	url = {<Go to ISI>://000172927000066},
	author = {Rundle, N. T. and Xu, L. and Andersen, R. J. and Roberge, M.}
}
@article {4389,
	title = {High-throughput assay for G(2) checkpoint inhibitors and identification of the structurally novel compound isogranulatimide},
	journal = {Cancer Research},
	volume = {58},
	number = {24},
	year = {1998},
	note = {ISI Document Delivery No.: 148HTTimes Cited: 83Cited Reference Count: 39},
	month = {Dec},
	pages = {5701-5706},
	type = {Article},
	abstract = {Treatment of cancer cells lacking p53 function with G(2) checkpoint inhibitors sensitizes them to the toxic effects of DNA damage and has been proposed as a strategy for cancer therapy. However, few inhibitors are known, and they have been found serendipitously, We report the development of a G(2) checkpoint inhibition assay that is suitable for high-throughput screening and its application to a screen of 1300 natural extracts. We present the isolation of a new G(2) checkpoint inhibitor, the structurally novel compound isogranulatimide. In combination with gamma-irradiation, isogranulatimide selectively kills MCF-7 cells lacking p53 function.},
	keywords = {ANTITUMOR DRUG, BHK CELLS, CAFFEINE, CELL-CYCLE CHECKPOINTS, DNA-DAMAGE, HELA-CELLS, mitosis, P34(CDC2) KINASE, P53 FUNCTION, PREMATURE, PROTEIN KINASE-C},
	isbn = {0008-5472},
	url = {<Go to ISI>://000077499800017},
	author = {Roberge, M. and Berlinck, R. G. S. and Xu, L. and Anderson, H. J. and Lim, L. Y. and Curman, D. and Stringer, C. M. and Friend, S. H. and Davies, P. and Vincent, I. and Haggarty, S. J. and Kelly, M. T. and Britton, R. and Piers, E. and Andersen, R. J.}
}
