Antimicrobial Peptides and Cancer: Potential Use of Antimicrobial-Like Peptides in Chemotherapy

Antimicrobial peptides (AMPs) constitute host defense peptides found among insects, fish, amphibians, and mammals including man. The targets of AMPs are gram-negative and gram-positive bacteria, fungi, enveloped viruses, and transformed/cancerous cells. The AMPs are broad spectrum antibiotics which display the propensity to serve as therapeutic agents not only in infectious disease, but also in human cancer. AMPs demonstrate unique properties which include cell membrane penetration, destabilization of biological membranes, ability to form and/or interact with membrane channels, and the capability to modulate host immune responses. The three types of AMPs consists a) naturally-occurring; b) artificially synthesized; and c) cleaved peptide fragments from blood and extracellular matrix proteins. The present treatise presents one such example of an AMP-like peptide derived from a naturally-occurring human protein as a potential candidate for future cancer therapy. The biological activities of human AMP-like peptides as cancer therapeutic agents are reviewed and reported in multiple in vitro and in vivo cancer assays. The possibility of using such human protein-derived peptides as primary and adjunct cancer therapeutic agents is addressed.