Effects of Dandelion Root Extract (DRE) on CD44(+) and CD44(-) for Cell Viability

Abstract

Dandelion (Taraxacum officinale) root extract (DRE) is known to have anti- cancer activity against breast cancer, leukemia, prostate cancer, colorectal cancer and melanoma cells (1-5). Even though this plant is sometime seen as a pesky weed in our culture, in other cultures such as Chinese, Middle Eastern, Native Americans, and East Indians, it is appreciated for its medicinal effects against cancer and other diseases ranging from indigestion, heartburn and kidney disease. Based on the reported anti-cancer cell activities of DRE, particularly on aggressive cancer cells but not on normal cells, we decided to study its activity on two breast cancer cell lines, one expressing the cell membrane receptor CD44 (i.e., MCF-7/CD44) and a control cell line negative for CD44 expression (i.e., MCF-7/pLXIN) (3, 6). The MCF-7/CD44 cell line is an aggressive multidrug resistant, very migratory and in vitro invasive while the MCF-7/pLXIN cell line is not. We hypothesize that aqueous DRE will have differential anti-cancer cell activity on these two cell lines based on their CD44 expression status. A cell viability assay (MTS) carried out after 48 hrs of DRE treatment showed that MCF-7/CD44 cells were more sensitive to DRE (when extracted in boiled PBS) compared to MCF-7/pLXIN cells. Treatment of these cell lines with non-boiled PBS extracted DRE showed no cell toxicity effect. This data validated our hypothesis and suggest that DRE might be effective at targeting CD44-expressing aggressive breast cancer cells.