[Perspective of personalized (precise) cancer therapy based on predictive biomarkers]

The epidermal growth factor receptor (EGFR), a receptor tyrosine kinase, triggers a downstream signaling cascade through areas such as the RAS-RAF-MAPK, PI3K-AKT and JAK-STAT pathways, which are involved in cell proliferation, dedifferentiation and inhibition of apoptosis. Two anti-EGFR monoclonal antibodies, cetuximab and panitumumab, are currently available for the treatment of metastatic colorectal cancer. KRAS is a validated predictive biomarker for anti-EGFR therapy and tumor KRAS status should be determined whenever anti-EGFR therapy is considered in the treatment of metastatic colorectal cancer. On the other hand, the promising biomarkers such as NRAS, BRAF and PIK3CA for anti-EGFR monoclonal antibody, and pVEGF-A for bevacizumab have been reported. We review the biomarkers associated with personalized therapy in colorectal cancer.