Estrogen receptor-dependent genomic expression profiles in breast cancer cells in response to fatty acids

CONTEXT: The estrogen receptor (ER) status in breast cancer plays a major role in the progression and metastatic potential of breast cancer in women. Breast cancer cells lacking the ER are usually more advanced and more difficult to treat than ER+ breast cancer cells. ER− women have more advanced breast cancer at the time of diagnosis than ER+ women. ER− breast cancer cells in women, regardless of age, are more likely to have tumor Grade III or IV with fewer Grade I and II tumor stages combined for each individual stage group. Studies have suggested a strong correlation between fat intake and the elevated risk of ER+ breast cancer cells. MATERIALS AND METHODS: We studied the role of ER status on the gene expression in breast cancer cells in response to omega-3 and omega-6 fatty acids using microarrays. We have studied gene expression patterns in 8 breast cancer cell lines (4 ER− and 4 ER+) in response to Eicosapentanoic (EPA) and Arachidonic (AA) acids. STATISTICAL ANALYSIS: Analysis of Variance (ANOVA) t-test analysis was carried out to identify genes differentially expressed between the two groups. RESULTS: We identified genes which were significantly correlated with the ER status when breast cancer cells were treated with these fatty acids. CONCLUSION: We have determined ER-related gene expression patterns in breast cancer cells in response to fatty acids. Additional studies of these biomarkers may enlighten the importance of the ER status on the mechanistic and therapeutic roles of fatty acids in breast cancer.