Crocus sativus L. (saffron) has been used as a spice and as a medicine for the past four thousand years. Recently, saffron has been well documented to possess anticancer effects on primary tumors. However studies of its antimetastatic potential are lacking. The present study is a comparative investigation of the antimetastatic effects of saffron carotenoids, crocin and crocetin, on triple negative metastatic breast cancer cells (4T1) and their effects on the Wnt/β-catenin pathway. It was found that treatment of 4T1 cells with crocin and crocetin resulted in the inhibition of viability in a dose-dependent manner. Scratch and Transwell chamber assays showed that the nontoxic doses of crocin and crocetin significantly inhibited migration, cell mobility, and invasion, also attenuating adhesion to extracellular matrix. Crocin downregulated mRNA expression of FZD7, NEDD9, VIM, and VEGF-α genes and upregulated E-CAD. Crocin and crocetin exhibited comparable anti-invasion properties on 4T1 cells. However, crocin and crocetin exerted more pronounced antimigration and antiadhesion potency, respectively. Furthermore, we showed that the antimetastatic effects of crocin can occur through interfering with the Wnt/β-catenin pathway.
Keywords: Wnt/β-catenin; anti-invasion; antiadhesion; antimigration; breast cancer; saffron carotenoids.