Role of lycopene in the control of ROS mediated cell growth. Implication in cancer prevention

Dietary intakes of tomatoes and tomato products containing lycopene have been shown to be associated with decreased risk of chronic diseases, such as cancer. Although several mechanisms, including modulation of gap junction communication and enhancement of immune system, are thought to be implicated in its beneficial activities, evidence is accumulating to suggest that lycopene may act as a modulator of intracellular reactive oxygen species (ROS) and, therefore, control ROS-mediated cell growth. According with this, at high concentration, ROS have been reported to be hazardous for living organisms, whereas at moderate concentrations, they play an important role as regulatory mediators in signalling processes regulating cell growth. In this review, we report the available evidence on a role of lycopene as a redox agent in cell proliferation, differentiation and apoptosis. In particular, we focused our attention on lycopene modulation of redox-sensitive targets in signalling cascades: receptor-mediated signalling pathways, protein tyrosine phosphatases, protein kinases, MAPK cascade, cytosolic calcium concentration, transcription factors, such as NF-kB and AP-1, glutathione levels. Moreover, we speculate on the possible influence that lycopene may have as a redox agent in human cancer.