The correlation between diet and variation in gene-expression is an important field which could be considered to approach
cancer pathways comprehension. We examined the effects of
lycopene on
breast cancer cell lines using pangenomic arrays.
Lycopene is derived predominantly from tomatoes and tomato products and there is some epidemiologic evidence for a preventive role in
breast cancer. Previously, we investigated
lycopene in
breast cancer using a dedicated
breast cancer microarray. To confirm these results and explore pathways other than those implicated in
breast cancer, for this study we used pangenomic arrays containing 25,000
oligonucleotides. This in vitro study assayed two human
mammary cancer cell lines (MCF-7 and MDA-MB-231), and a fibrocystic breast cell line (MCF-10a) treated or not with 10 microM
lycopene for 48 h. A competitive hybridization was performed between Cy3-labeled
lycopene treated
RNA and Cy5-labeled untreated
RNA to define differentially expressed genes. Using t-test analysis, a subset of 391 genes was found to be differentially modulated by
lycopene between
estrogen-positive cells (MCF-7) and
estrogen-negative cells (MDA-MB-231, MCF-10a). Hierarchical clustering revealed 726 discriminatory genes between
breast cancer cell lines (MCF-7, MDA-MB-231) and the fibrocystic breast cell line (MCF-10a). Modified gene expression was observed in various molecular pathways, such as apoptosis, cell communication, MAPK and cell cycle as well as
xenobiotic metabolism,
fatty acid biosynthesis and gap junctional intercellular communication.