Building better magic bullets--improving unconjugated monoclonal antibody therapy for cancer.

The potential of monoclonal antibodies to effectively treat cancer is beginning to be widely acknowledged. Advances in antibody engineering make it possible to produce various recombinant proteins that exploit the specificity of the antibody-combining site to manipulate tumour-related signalling, and to stimulate anti-tumour immune responses. Future advances in the field will rely on the improved identification of functional antibody targets to perturb cancer-relevant signalling, and by the improved selection of tumours that can be effectively treated. These advances will be complemented by the use of antibodies that induce clinically meaningful host-protective immune responses. But, can we afford this progress?