Melatonin enhances the inhibitory effect of aminoglutethimide on aromatase activity in MCF-7 human breast cancer cells

摘要

The inhibition of the aromatase-induced intratumoral estrogen synthesis is one of the main anticancer pharmacological strategies. The aim of this paper was to study if a melatonin pretreatment prior to aminoglutethimide increases the efficiency of the aromatase inhibitor used in treating breast cancer. Aminoglutethimide (100 μM) and melatonin (1 nM) significantly decreased cellular aromatase activity in unpretreated MCF−7 cells. A sequential regimen of melatonin (1 nM) followed 24 h later by aminoglutethimide (100 μM) induced a significantly higher decrease in MCF-7 cell aromatase activity to below the values obtained in unpretreated cells. Melatonin treatment inhibited aromatase mRNA expression in unpretreated cells and a sequential treatment of cells with melatonin followed by aminoglutethimide induced a significant inhibition in the aromatase mRNA expression as compared to cells exposed to the same doses of aminoglutethimide, but without melatonin pretreatment.