Estonian folk traditional experiences on natural anticancer remedies: From past to the future

Context: Despite diagnostic and therapeutic advancements, the burden of cancer is still increasing worldwide. Toxicity of current chemotherapeutics to normal cells and their resistance to tumor cells highlights the urgent need for new drugs with minimal adverse side effects. The use of natural anticancer agents has entered into the area of cancer research and increased efforts are being made to isolate bioactive products from medicinal plants. Objective: To lead the search for plants with potential cytotoxic activity, ethnopharmacological knowledge can give a great contribution. Therefore, the attention of this review is devoted to the natural remedies traditionally used for the cancer treatment by Estonian people over a period of almost 150 years. Methods: Two massive databases, the first one stored in the Estonian Folklore Archives and the second one in the electronic database HERBA (http://herba.folklore.ee/), containing altogether more than 30 000 ethnomedicinal texts were systematically reviewed to compile data about the Estonian folk traditional experiences on natural anticancer remedies. Results and conclusion: As a result, 44 different plants with potential anticancer properties were elicited, 5 of which [Angelica sylvestris L. (Apiaceae), Anthemis tinctoria L. (Asteraceae), Pinus sylvestris L. (Pinaceae), Sorbus aucuparia L. (Rosaceae), and Prunus padus L. (Rosaceae)] have not been previously described with respect to their tumoricidal activities in the scientific literature, suggesting thus the potential herbal materials for further investigations of natural anticancer compounds.