cRGD functionalised nanocarriers for targeted delivery of bioactives

The integrins α_vβ₃ play a very imperative role in angiogenesis and are overexpressed in endothelial cells of the tumour. Recent years have witnessed huge exploration in the field of α_vβ₃ integrin-mediated bioactive targeting for treatment of cancer. In these studies, the cRGD peptide has been employed extensively owing to their binding capacity to the α_vβ₃ integrin. Principally, RGD-based approaches comprise of antagonist molecules of the RGD sequence, drug-RGD conjugates, and most importantly tethering of the nanocarrier surface with the RGD peptide as targeting ligand. Targeting tumour vasculature or cells via cRGD conjugated nanocarriers have emerged as a promising technique for delivering chemotherapeutic drugs and imaging agents for cancer theranostics. In this review, primary emphasis has been given on the application of cRGD-anchored nanocarriers for targeted delivery of drugs, imaging agents, etc. for tumour therapy.

EPR effect based nanocarriers targeting for treatment of cancer

<p>The enhanced permeability and retention (EPR) effect is a unique phenomenon of solid tumors related to their anatomical and pathophysiological differences from normal tissues. In solid tumors, angiogenesis leads to high vascular density. Large gaps exist between endothelial cells in tumor blood vessels, which lead to selective extravasations and retention of macromolecular drugs. This EPR effect served as a basis for development of macromolecular anticancer therapy. There are various factors, which lead to a significantly increased EPR effect and enhanced antitumor drug effects as well. This review discusses the unique anatomy of tumor vessels, molecular mechanisms of factors related to the EPR effect and the role of the EPR effect in the intratumoral delivery of protein and peptide drugs, macromolecular drugs and drug-loaded long-circulating nanocarriers.</p>