For example, EGCG inhibits multiple RTKs (Receptor Tyrosine Kinase) as the IGF/IGF1R system, EGFR, and HER2 receptors, which play key roles in CRC cell proliferation (Shimizu et al., 2005; Adachi et al., 2008, 2009). Here, IGF1R is linked to colorectal carcinoma.