A study in the May issue of Food and Chemical Toxicology compared the anticancer effects of quercetin and its water-soluble sulfated derivative, quercetin-5′,8-disulfonate (QS), in human colon cancer LoVo cells and breast cancer MCF-7 cells. It was found that both quercetin and QS can inhibit the growth of cancer cells in a dose-dependent manner. Moreover, quercetin and QS could mediate the cell-cycle arrest principally in the S phase after 24 hours of treatment with the two tumor cells. It was also found that 69.6% of LoVo cells and 90.6% of MCF-7 cells entered the early phase of apoptosis (cell death) when treated with a certain dosage of QS for 48 hours.
Taken together, the novel sulfated derivative of quercetin and quercetin alone possess strong antitumor activity via a ROS-dependent apoptosis pathway, and has the excellent potential to be developed into an antitumor precursor compound.