Low Doses of Thymoquinone and Ferulic Acid in Combination Effectively Inhibit Proliferation of Cultured MDA-MB 231 Breast Adenocarcinoma Cells.

Thymoquinone (TQ) and Ferulic Acid (FA) are natural ingredients from Nigella sativa and Ferula asafetida, respectively. Individually both TQ and FA have shown anticancer properties in a variety of cancer cell lines. We investigated the combination effect of lower doses of TQ and FA on proliferation, apoptosis, and cell cycle of a breast cancer cell line MDA-MB 231. Cells were treated with various concentrations of TQ, FA and various combinations of TQ + FA for 48 hrs. Cell proliferation was assessed by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay, whereas cell cycle and apoptosis were measured with flow-cytometry after propidium iodide staining and Annexin-V/FITC staining, respectively. TQ (50 and 100 microM) and FA (450 microM), and all the doses of TQ and FA in combination significantly decreased cell proliferation. 25 microM TQ and 250 microM FA individually did not affect cell proliferation but in combination significantly reduced cell proliferation. TQ at 50 microM caused significant apoptosis, whereas, FA did not affect apoptosis. These in vitro data suggest that in combination, relatively lower doses of TQ and FA are effective in decreasing cancer cell proliferation, and thus have anticancer therapeutic potential. Further research is needed to corroborate these findings in an animal model of breast cancer.