An aqueous extract of Fagonia cretica induces DNA damage, cell cycle arrest and apoptosis in breast cancer cells via FOXO3a and p53 expression

Lam, Matthew, Carmichael, Amtul and Griffiths, Helen (2012). An aqueous extract of Fagonia cretica induces DNA damage, cell cycle arrest and apoptosis in breast cancer cells via FOXO3a and p53 expression. PLoS ONE, 7 (6),

Abstract

Background - Plants have proved to be an important source of anti-cancer drugs. Here we have investigated the cytotoxic action of an aqueous extract of Fagonia cretica, used widely as a herbal tea-based treatment for breast cancer. Methodology/Principal Findings - Using flow cytometric analysis of cells labeled with cyclin A, annexin V and propidium iodide, we describe a time and dose-dependent arrest of the cell cycle in G0/G1 phase of the cell cycle and apoptosis following extract treatment in MCF-7 (WT-p53) and MDA-MB-231 (mutant-p53) human breast cancer cell lines with a markedly reduced effect on primary human mammary epithelial cells. Analysis of p53 protein expression and of its downstream transcription targets, p21 and BAX, revealed a p53 associated growth arrest within 5 hours of extract treatment and apoptosis within 24 hours. DNA double strand breaks measured as ?-H2AX were detected early in both MCF-7 and MDA-MB-231 cells. However, loss of cell viability was only partly due to a p53-driven response; as MDA-MB-231 and p53-knockdown MCF-7 cells both underwent cell cycle arrest and death following extract treatment. p53-independent growth arrest and cytotoxicity following DNA damage has been previously ascribed to FOXO3a expression. Here, in MCF-7 and MDA-MB-231 cells, FOXO3a expression was increased significantly within 3 hours of extract treatment and FOXO3 siRNA reduced the extract-induced loss of cell viability in both cell lines. Conclusions/Significance - Our results demonstrate for the first time that an aqueous extract of Fagonia cretica can induce cell cycle arrest and apoptosis via p53-dependent and independent mechanisms, with activation of the DNA damage response. We also show that FOXO3a is required for activity in the absence of p53. Our findings indicate that Fagonia cretica aqueous extract contains potential anti-cancer agents acting either singly or in combination against breast cancer cell proliferation via DNA damage-induced FOXO3a and p53 expression.

Publication DOI: https://doi.org/10.1371/journal.pone.0040152
Divisions: Life & Health Sciences
Life & Health Sciences > Biosciences
Additional Information: © 2012 Lam et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. Correction: An aqueous extract of Fagonia cretica induces DNA damage, cell cycle arrest and apoptosis in breast cancer cells via FOXO3a and p53 expression (PLoS ONE (2014) 9, 7 (e102655) DOI: 10.1371/journal.pone.0102655)
Uncontrolled Keywords: forkhead transcription factors,tumor suppressor protein p53,apoptosis,DNA damage,plant extracts,humans,breast neoplasms,tumor cell line,cell cycle,female,Agricultural and Biological Sciences(all),Biochemistry, Genetics and Molecular Biology(all),Medicine(all)
Full Text Link: http://www.plos ... al.pone.0040152
http://www.plos ... al.pone.0102655
Related URLs: http://www.scop ... tnerID=8YFLogxK (Scopus URL)
http://www.scop ... tnerID=8YFLogxK (Scopus URL)
Published Date: 2012-06-27
Authors: Lam, Matthew
Carmichael, Amtul
Griffiths, Helen ( 0000-0002-2666-2147)

Download

[img]

Version: Accepted Version

License: Creative Commons Attribution


Export / Share Citation


Statistics

Additional statistics for this record