Garlic (Allium sativum L.) Organosulfur Compounds Inhibit Breast Cancer Cell Proliferation by Decreasing Steroid Sulfatase Levels

Background/aim: Breast cancer is mostly affected by estrogen, which promotes proliferation, tumorigenesis, and cancer progression. Estrogen sulfotransferase (SULT1E1) catalyzes sulfation to inactivate estrogens, whereas steroid sulfatase (STS) catalyzes estrogen sulfate hydrolysis to activate estrogens in breast cancer cells. Three major organosulfur compounds in garlic (Allium sativum L.), diallyl sulfide (DAS), diallyl disulfide (DADS), and diallyl trisulfide (DATS), are known to exert anticancer effects against breast cancer. This study aimed to investigate the effects of these compounds on proliferation and SULT1E1 and STS protein levels in breast cancer cells.

Materials and methods: Cell proliferation and SULT1E1 and STS protein levels in MCF-7 breast cancer cells treated with DAS, DADS, and DATS were analyzed via 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyltetrazolium bromide and western blotting assays, respectively.

Results: DADS and DATS concentration-dependently inhibited MCF-7 cell proliferation. Specifically, DATS, followed by DADS and DAS (each 100 μmol/l), demonstrated the most significant inhibition of cell proliferation. DADS and DATS also decreased the STS protein levels. Notably, DAS, DADS, and DATS did not affect the SULT1E1 protein levels. In MCF-7 cells treated with DAS, DADS, and DATS, cell proliferation was positively correlated with STS protein expression.

Conclusion: Overall, our findings highlight the potential of DADS and DATS as promising agents for preventing and treating breast cancer by decreasing STS protein expression and suppressing active estrogen levels in breast cancer cells.