Nanotechnological Strategies for Targeted Therapies

Joseph Kost, Chemical Engineering, Ben-Gurion University, Beer-Sheva, Israel

Nanotechnology has the potential to revolutionize cancer and other therapies. Advances in protein engineering and materials science have contributed to novel nanoscale targeting approaches that may bring new hope to patients. Several nanocarriers have been approved for clinical use. However, to date, there are only a few clinically approved nanocarriers with drugs to selectively bind and target cancer cells. Nanoparticles used as drug delivery carriers consist of different biodegradable materials such as natural or synthetic polymers, lipids, or metals. Nanoparticles are taken up by cells more efficiently than larger micromolecules and therefore, could be used as effective delivery systems. For therapeutic applications, drugs can either be integrated in the matrix of the particle or attached to the particle surface. A drug targeting system should be able to control the fate of a drug entering the biological environment. An effective approach for achieving efficient drug delivery would be to develop nanosystems based on the understanding of their interactions with the biological environment, cellular and intracellular barriers, target cell population and cell-surface receptors, mechanism and site of drug action, drug retention, molecular mechanisms, and pathobiology of the disease under consideration. Reduced efficacy could be due to instability of therapeutic agent, cellular and intracellular transport barriers, toxicity of the carrier, changes in signaling pathways with the progression of disease, or drug degradation. Better understanding of the mechanism of uptake, intracellular trafficking, retention, and protection from degradation inside a cell are required for enhancing the efficacy of the therapeutic agent. Physical approaches to increase efficacy and targeting to specific tissues have been also studies. In the presentation the drug delivery aspects of nanomedicine, the molecular mechanisms underlying the interactions of nanoparticles with cell-surface receptors, biological responses and ultrasound as a targeting tool and its effect on cellular transport would be discussed.