Mushrooms as potential natural cytostatics

Abstract

Cancer is the second cause of morbidity and mortality worldwide, i.e., half of the men and more than a third of women of the world population get sick with some type of cancer during a lifetime, and one-quarter of all adults die of this disease. Common treatments, chemo- and radiotherapy, are not highly effective, give satisfactory results only in the treatment of early cancer development stages or have no any effect on some cancer types, and commonly cause numerous side effects. Therefore, alternative medicine based on various natural sources attracts great attention nowadays. Although mushrooms, their extracts, and isolated metabolites cannot be considered drugs, they are a type of important dietary supplement, i.e., functional food or nutraceuticals, and could be used as auxiliary natural cytostatics. They are highly selective, i.e., not toxic or almost nontoxic to normal cells, do not cause any side effects, and even reduce harmful effects caused by conventional treatments, and finally, resistance to them cannot be developed. Mushroom extracts or biologically active compounds isolated from them affect cytotoxic activity on a few mechanisms: stimulation of immune system; antioxidative, antimutagenic, and anti-inflammatory activity; regulation of expression of regulators of some cell processes; cell cycle arrest and apoptosis; disturbance of DNA synthesis and structure; changes in morphology and mobility of malignant cells; and antiangiogenic activity.