Expression patterns of fatty acid binding proteins in breast cancer cells.

We studied the expression levels of fatty acid binding proteins in breast normal and cancer cell lines. Liver fatty acid binding protein (L-FABP) and intestine fatty acid binding proteins were shown to be up-regulated in breast cancer cell lines while adipose- and epidermal-fatty acid binding proteins were down regulated in breast cancer cells compared to normal breast cell lines. We have previously shown that blocking the expression of L-FABP resulted in remarkable effects on apoptosis and cell proliferation of prostate cancer cell lines (Hammamieh et al 2004). To study the mechanism of effect of the liver fatty acid binding protein in breast cancer cells, we designed an antisense oligodeoxynucleotide to block the production of liver-FABP in MCF-7 cells. The antisense was shown to inhibit the expression of L-FABP and to induce apoptosis in MCF-7 cells. This study examines the mechanism by which L-FABP antisense regulates proliferation and apoptosis in breast cancer cell lines. We used human cDNA microarrays to explore differentially expressed genes in MCF-7 breast cancer cells treated with L-FABP antisense oligonucleotide. Some of the genes that were differentially expressed were confirmed using quantitative RT-PCR. Genes related to cell growth, proliferation and angiogenesis showed significant variations. This suggests a possible use of these antisense ODNs as therapeutic agents for breast cancer in future.