ErbB3 is frequently amplified or over-expressed in breast, lung, liver, colon, gastric, and prostate cancer (Desbois-Mouthon, 2010), and while there is no evidence to suggest that ErbB3 carries oncogenic mutations, somatic mutations have been found to occur in 12% of colorectal cancers (Jaiswal et al., 2013). This evidence concerns the gene ERBB3 and colorectal cancer.