New Insight on Solute Carrier Family 27 Member 6 (SLC27A6) in Tumoral and Non-Tumoral Breast Cells

Long-chain fatty acids are the most abundant fatty acids and are essential for various physiological processes. Translocation of long-chain fatty acids across cell membrane is dependent on transport proteins. Solute carrier family 27 member 6 (SLC27A6) is a transport protein which mediates long-chain fatty acid uptake. The bioinformatic analysis revealed that the expression of SLC27A6 in non-tumoral breast tissue was higher than that in tumoral breast cancer in clinic samples. When SLC27A6 expression in non-tumorigenic cell H184B5F5/M10 was repressed, the fatty acids uptake capacity and cell proliferation was inhibited, and cell cycle was delayed. The protein expression of cell cycle regulators including cell division protein kinase 4 (CDK4), CDK6, and cyclin D1 was significantly decreased in SLC27A6-silenced H184B5F5/M10. By contrast, relatively low SLC27A6 expression in tumorigenic breast cancer cell Hs578T when compared to H184B5F5/M10. Repressing SLC27A6 expression did not affect these phenotypes in Hs578T. The interaction network of SLC27A6 was further investigated via STRING database. The function of these SLC27A6-associated proteins mainly involved in lipid biosynthesis, fatty acid metabolic process, and fatty acid transport. In conclusion, this study reveals inverse correlation between SLC27A6 expression and tumoral tissues and provides a new insight into SLC27A6-mediated cell growth and cell cycle regulation in non-tumorigenic breast cells.