Period-2: a tumor suppressor gene in breast cancer

Xiang, S., Coffelt, S. B. , Mao, L., Yuan, L., Cheng, Q. and Hill, S. M. (2008) Period-2: a tumor suppressor gene in breast cancer. Journal of Circadian Rhythms, 6(1), p. 4. (doi:10.1186/1740-3391-6-4) (PMID:18334030) (PMCID:PMC2365929)

124068.pdf - Published Version



Previous reports have suggested that the ablation of the Period 2 gene (Per 2) leads to enhanced development of lymphoma and leukemia in mice. Employing immunoblot analyses, we have demonstrated that PER 2 is endogenously expressed in human breast epithelial cell lines but is not expressed or is expressed at significantly reduced level in human breast cancer cell lines. Expression of PER 2 in MCF-7 breast cancer cells significantly inhibited the growth of MCF-7 human breast cancer cells, and, when PER 2 was co-expressed with the Crytochrome 2 (Cry 2) gene, an even greater growth-inhibitory effect was observed. The inhibitory effect of PER 2 on breast cancer cells was also demonstrated by its suppression of the anchorage-independent growth of MCF-7 cells as evidenced by the reduced number and size of colonies. A corresponding blockade of MCF-7 cells in the G1 phase of the cell cycle was also observed in response to the expression of PER 2 alone or in combination with CRY 2. Expression of PER 2 also induced apoptosis of MCF-7 breast cancer cells as demonstrated by an increase in PARP [poly (ADP-ribose) polymerase] cleavage. Finally, our studies demonstrate that PER 2 expression in MCF-7 breast cancer cells is associated with a significant decrease in the expression of cyclin D1 and an up-regulation of p53 levels.

Item Type:Articles
Additional Information:This work was supported by Army DOD DAMD grant 17-03-1-07 and by NIH/NCI grant 5RO1 CA 54152-14 to S.M. Hill.
Glasgow Author(s) Enlighten ID:Coffelt, Dr Seth
Authors: Xiang, S., Coffelt, S. B., Mao, L., Yuan, L., Cheng, Q., and Hill, S. M.
College/School:College of Medical Veterinary and Life Sciences > Institute of Cancer Sciences
Journal Name:Journal of Circadian Rhythms
Publisher:Ubiquity Press
ISSN (Online):1740-3391
Copyright Holders:Copyright © 2008 Xiang et al.
First Published:First published in Journal of Circadian Rhythms 6(4)
Publisher Policy:Reproduced under Creative Commons License

University Staff: Request a correction | Enlighten Editors: Update this record