Article

Apigenin causes G(2)/M arrest associated with the modulation of p21(Cip1) and Cdc2 and activates p53-dependent apoptosis pathway in human breast cancer SK-BR-3 cells.

Plant Resources Research Institute, Duksung Women's University,Tobong-ku, Seoul, South Korea.
The Journal of nutritional biochemistry (impact factor: 4.29). 04/2009; 20(4):285-90. DOI:10.1016/j.jnutbio.2008.03.005
Source: PubMed

ABSTRACT We studied the effects of apigenin on the cell cycle distribution and apoptosis of human breast cancer cells and explored the mechanisms underlying these effects. We first investigated the antiproliferative effects in SK-BR-3 cells exposed to between 1 and 100 microM apigenin for 24, 48 and 72 h. Apigenin significantly inhibited cell proliferation at concentrations over 50 microM, regardless of exposure time (P<.05), and resulted in significant cell cycle arrest in the G(2)/M phase after 48 h of treatment at high concentrations (50 and 100 microM; P<.05). To investigate the regulatory proteins of cell cycle arrest affected by apigenin, we treated cells with 50 and 100 microM apigenin for 72 h. Apigenin caused a slight decrease in cyclin D and cyclin E expression, with no change in CDK2 and CDK4. In addition, the apigenin-induced accumulation of the cell population in the G(2)/M phase resulted in a decrease in CDK1 together with cyclin A and cyclin B. In an additional study, apigenin also increased the accumulation of p53 and further enhanced the level of p21(Cip1), with no change in p27(Kip1). The expression of Bax and cytochrome c of p53 downstream target was increased markedly at high concentration treatment over 50 microM apigenin. Based on our findings, the mechanism by which apigenin causes cell cycle arrest via the regulation of CDK1 and p21(Cip1) and induction of apoptosis seems to be involved in the p53-dependent pathway.

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Keywords

100 microM apigenin
 
50 microM
 
50 microM apigenin
 
72 h. Apigenin
 
antiproliferative effects
 
apigenin causes cell cycle arrest
 
apigenin-induced accumulation
 
cell cycle arrest
 
cell cycle distribution
 
cell population
 
concentration treatment
 
concentrations
 
cyclin D
 
cyclin E expression
 
cytochrome c
 
human breast cancer cells
 
p53 downstream target
 
significant cell cycle arrest
 
SK-BR-3 cells
 
slight decrease