IGF1 and colorectal cancer: In a crossover study by Vrieling et al., lycopene was observed to increase the concentrations of circulating insulin-like growth factor binding proteins (IGFBP)-1 and −2, thereby reducing the binding of IGF-I to its receptor, which may indirectly result in decreased bioavailability of IGF-I, potentially playing a preventive role in the development of colorectal cancer (Vrieling et al., 2007) (Figure 3).