Recent developments in colorectal cancer treatment by monoclonal antibodies.

A growing understanding of the molecular mechanisms involved in cancer biology and continuous refinement of available technologies for drug discovery have prompted the development of new therapeutic tools targeting specific cancer-associated molecular pathways. Among these so-called biological therapies, monoclonal antibodies have now reached the time of clinical application. Besides initial development of the murine antibody edrecolomab, the impact of monoclonal antibodies on cancer therapy has recently been clearly demonstrated in colorectal cancer by targeting two major pathways critical to tumourigenesis: the epidermal growth factor receptor (EGFR) and vascular endothelial growth factor (VEGF) signalling pathways. These antibodies showed significant clinical activity in advanced colorectal cancer, especially when combined with chemotherapy. This paper reviews the status of the monoclonal chimeric antibody cetuximab (Erbitux) and other anti-EGFR antibodies, and of bevacizumab (Avastin; an anti-VEGF humanised monoclonal antibody), in colorectal cancer treatment.