Article

Ambient particulate matter induces alveolar epithelial cell cycle arrest: Role of G1 cyclins

Department of Pulmonary and Critical Care Medicine, Stanford University Medical Center, 300 Pasteur Drive, Stanford, CA 94305, USA.
FEBS Letters (Impact Factor: 3.34). 12/2007; 581(27):5315-20. DOI: 10.1016/j.febslet.2007.10.020
Source: PubMed

ABSTRACT We hypothesized that the ambient air pollution particles (particulate matter; PM) induce cell cycle arrest in alveolar epithelial cells (AEC). Exposure of PM (25microg/cm(2)) to AEC induced cells cycle arrest in G1 phase, inhibited DNA synthesis, blocked cell proliferation and caused decrease in cyclin E, A, D1 and Cyclin E- cyclin-dependent kinase (CDK)-2 kinase activity after 4h. PM induced upregulation of CDK inhibitor, p21 protein and p21 activity in AEC. SiRNAp21 blocked PM-induced downregulation of cyclins and AEC G1 arrest. Accordingly, we provide the evidence that PM induces AEC G1 arrest by altered regulation of G1 cyclins and CDKs.

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