Colorectal cancer (CRC) is a major cause of cancer morbidity and mortality in the world.1 Recently, promising molecularly targeted therapies have been developed, such as cetuximab (Erbitux®; Merck KGaA, Germany), an epidermal growth factor receptor (EGFR)-targeted monoclonal antibody, and bevacizumab (Avastin®; Genentech Inc., USA), a vascular endothelial growth factor (VEGF)-targeted monoclonal antibody, for treatment of metastatic CRC.2, 3 However, the clinical benefit of targeted therapy remains limited in CRC. This evidence concerns the gene VEGFA and colorectal cancer.