[The influence of melatonin on the immune system and cancer].

Melatonin has been shown to play a fundamental part in neuroimmunomodulation. Besides regulating the circadian rhythm it works as a natural antioxidant with immune stimulatory and anti-cancer properties. Melatonin is a regulator of haemopoiesis and modifies various cells and cytokines of the immune system. Also, melatonin elicits oncostatic properties in a variety of different tumour cell lines. A number of studies have documented that when given in combination with chemo-therapy to patients with disseminated disease, melatonin increases the overall one-year survival and reduces toxic side effects.