Abstract

One of the main challenges of oncology is to develop tumour-selective cancer therapeutics with increased potency and decreased side effects on normal organs. This review summarizes past research and current trends in development of affinity targeted cancer therapeutics. Tumour blood vessels are molecularly different from normal blood vessels. Peptide phage display screens can be used to identify homing peptides that bind to specific targets in the tumour vasculature. Corresponding synthetic peptides (and other ligands that bind to tumour specific vascular signatuure molecules such as antibodies and aptamers) are used for targeting low molecular weight drugs, biologicals and nanoparticle drugs into tumours to increase their therapeutic index. Molecular interactions that drive the specificity and activity of tumour-specific targeting ligands continue to be intensively investigated. An emerging class of tumour specific targeting ligands, Tumour Penetrating Peptides, trigger bulk extravascular transport in the tumour tissue and can be used for increasing the therapeutic effi cacy of unmodified cancer drugs.