Publication Date:
2012-06-19
Description:
Accumulating evidence indicates cancer stem cells (CSCs) possess the capability to resist DNA-damage induced cell death, whereas the mechanism is largely unknown. Here we show that cell cycle status and DNA damage response (DDR) in CSCs probably contribute to their survival in genotoxic insults. In this study, we isolated esophageal cancer stem cells (ECSCs) from esophageal cancer cell line EC9706 by side-population (SP) phenotype through flow cytometry and found that ECSCs preferentially stay quiescent as compared to the non-ECSCs and are more resistant to DNA damage agents. Further study revealed that ECSCs express a lower level of phosphoralated Stat3 and c-Myc, yet abnormally upregulated p27. More interestingly, different from non-ECSCs, when suffering DNA damage agents, ECSCs showed impaired induction of p53 and attenuated DNA-damage induced G 1 arrest, as well as declined DNA repair potential. These data indicated ECSCs probably employed an attenuated DDR to handle severe genomic insults. Conclusively, we infer that the damage-resistance ability of ECSCs is likely attributed to their slow-cycling status and avoidance of apoptosis or senescence triggered by an excessive DDR. J. Cell. Biochem. © 2012 Wiley Periodicals, Inc.
Electronic ISSN:
0091-7419
Topics:
Biology
,
Chemistry and Pharmacology
,
Medicine
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