![]() |
|
|


* Nutrition Division, Institute of Food Research, Colney Lane, Norwich, NR4 7UA, UK;
Wolfson Digestive Diseases Centre, University Hospital, Nottingham, NG7 2UH, UK; and
** School of Medicine, Health and Policy, University of East Anglia, Norwich, NR4 7TJ, UK
4To whom correspondence should be addressed. E-mail: richard.mithen{at}bbsrc.ac.uk.
Sulforaphane (SF), a dietary phytochemical obtained from broccoli, has been implicated in several physiological processes consistent with anticarcinogenic activity, including enhanced xenobiotic metabolism, cell cycle arrest, and apoptosis. In this study, we report changes in global gene expression in Caco-2 cells exposed to physiologically appropriate concentrations of SF, through the use of replicated Affymetrix array and RT-PCR experiments. After exposure to 50 µmol/L SF, 106 genes exhibited a >2-fold increase in expression and 63 genes exhibited a >2-fold decrease in expression. There were fewer changes in gene expression at lower SF concentrations. The majority of these genes had not previously been shown to be modulated by SF, suggesting novel mechanisms of possible anticarcinogenic activity, including induction of differentiation and modulation of fatty acid metabolism. The changes in the expression of 10 of these genes, together with 4 additional genes of biological interest, were further quantified in independent studies with RT-PCR. These genes include several that have recently become associated with carcinogenesis, such as Krüppel-like factor (KLF)4, a gut-enriched transcription factor associated with induction of differentiation and reduction in cellular proliferation; DNA (cytosine-5-)-methyltransferase 1, associated with methylation; and
-methylacyl-CoA racemase (AMACR), a marker associated with the development of colon and prostate cancer. The expression of 5 of these genes [caudal type homeo box transcription factor 2 (CDX-2), KLF4, KLF5, cyclin-dependent kinase inhibitor 1A (p21), and AMACR] was additionally studied after in vitro exposure to SF of surgically resected healthy and cancerous colon tissue from each of 3 patients. The study suggests the complex effects that SF has on gene expression and highlights several potential mechanisms by which the consumption of broccoli may reduce the risk of carcinogenesis.
KEY WORDS: colon cancer chemoprevention sulforaphane microarray KLF4 AMACR p21
This article has been cited by other articles:
![]() |
L. Mastrangelo, A. Cassidy, F. Mulholland, W. Wang, and Y. Bao Serotonin Receptors, Novel Targets of Sulforaphane Identified by Proteomic Analysis in Caco-2 Cells Cancer Res., July 1, 2008; 68(13): 5487 - 5491. [Abstract] [Full Text] [PDF] |
||||
![]() |
A. V. Gasper, M. Traka, J. R. Bacon, J. A. Smith, M. A. Taylor, C. J. Hawkey, D. A. Barrett, and R. F. Mithen Consuming Broccoli Does Not Induce Genes Associated with Xenobiotic Metabolism and Cell Cycle Control in Human Gastric Mucosa J. Nutr., July 1, 2007; 137(7): 1718 - 1724. [Abstract] [Full Text] [PDF] |
||||
![]() |
S. A. Ritz, J. Wan, and D. Diaz-Sanchez Sulforaphane-stimulated phase II enzyme induction inhibits cytokine production by airway epithelial cells stimulated with diesel extract Am J Physiol Lung Cell Mol Physiol, January 1, 2007; 292(1): L33 - L39. [Abstract] [Full Text] [PDF] |
||||
![]() |
A. V Gasper, A. Al-janobi, J. A Smith, J. R Bacon, P. Fortun, C. Atherton, M. A Taylor, C. J Hawkey, D. A Barrett, and R. F Mithen Glutathione S-transferase M1 polymorphism and metabolism of sulforaphane from standard and high-glucosinolate broccoli Am. J. Clinical Nutrition, December 1, 2005; 82(6): 1283 - 1291. [Abstract] [Full Text] [PDF] |
||||