Taraxacum officinale Extracts Exhibit Safe and Selective Anticancer Activity

Background: Medicinal plants have been and continue to be the primary source of treatment for many diseases. Taraxacum officinale (dandelion), has been used for hundreds of years as a traditional medical remedy for several diseases. However, the anti-cancer potential of this plant has not been fully screened. Genotoxicity screening which is an integral part of the evaluation of the safety of this plant is also lacking. Objective: The aim of this study was to investigate the cytotoxic and genotoxic effects of different extracts of T. officinale. Method: Plant sample was extracted in different solvents to prepare ethanol, methanol, chloroform and water extracts. These extracts were then tested for their ability to inhibit the proliferation of colorectal cancer (Caco-2), chronic myelogenous leukemia (K562), prostate cancer (PC-3), and breast cancer (MCF-7) cells. Cell viability was evaluated using MTT assay and the selectivity indices was determined with the aid of mortal human fibroblasts. Then the most active extract, chloroform extract, was used to detect the genotoxicity of the constituents on mice bone marrow cells. Results: The results showed that the T. officinale chloroform extract was found to be most effective against leukemia (K562) and prostate cancer (PC-3) cell lines. The extracts showed marked selectivity towards these cancer cells. Genotoxic studies revealed that genotoxic changes occurred after chloroform extract treatment, however, these changes were observed at the very high concentrations only. Conclusion: The results suggest that T. officinale exhibits selective anti-tumor activity and it is safe for use.