Effect of aluminium on migration of oestrogen unresponsive MDA-MB-231 human breast cancer cells in culture.

Aluminium (Al) has been measured in human breast tissue, and may be a contributory factor in breast cancer development. At the 10th Keele meeting, we reported that long-term exposure to Al could increase migratory properties of oestrogen-responsive MCF-7 human breast cancer cells suggesting a role for Al in the metastatic process. We now report that long-term exposure (20-25 weeks) to Al chloride or Al chlorohydrate at 10(-4) M or 10(-5) M concentrations can also increase the migration of oestrogen unresponsive MDA-MB-231 human breast cancer cells as measured using time-lapse microscopy and xCELLigence technology. In parallel, Al exposure was found to give rise to increased secretion of active matrix metalloproteinase MMP9 as measured by zymography, and increased intracellular levels of activated MMP14 as measured by western immunoblotting. These results demonstrate that Al can increase migration of human breast cancer cells irrespective of their oestrogen responsiveness, and implicate alterations to MMPs as a potential mechanism worthy of further study.