Anticancer lignans--from discovery to biotechnology.

Malignant diseases are the second mortality cause within the human population. Despite the serious progress in establishing and introduction of novel specifically targeted drugs the therapy of these diseases remains severe medical and social problem. Some of the most effective cancer treatments to date are natural products or compounds derived from plant products. Isolation of anticancer pharmaceuticals from plants is difficult due to their extremely low concentrations. The industry currently lacks sufficient methods for producing all of the desired plant-derived pharmaceutical molecules. Some substances can only be isolated from extremely rare plants. Plant cell cultures are an attractive alternative source to whole plant for the production of high-value secondary metabolites. The biotechnological method offers a quick and efficient method for producing these high-value medical compounds in cultivated cells. Due to the pharmaceutical importance and the low content in the plants the present review focuses on discovery and alternative production systems for anticancer lignans--aryltetralin and arylnaphthalene lignans. The aim is to focus on recent progress of in vitro production of anticancer lignans, together with structure elucidation, the methods of increasing the levels of desired substances in plant cell and tissue cultures in general. Experience of different authors, working worldwide on plant biotechnology, has been discussed to show positive results in experiments.