February 8, 2010 A Nano-Delivery System that Leads Anticancer Drugs Directly to Cancerous Cells.

Technion researchers have developed a nano-delivery system made up of a chemical connection between a polysugar, produced from the cypress tree, with folic acid and an anticancer drug. The delivery system leads the drug directly to the cancerous cell and releases it inside the cell. Thus the cancerous cell is destroyed without causing any damage to the healthy cells around it.

“We looked for a polymer that would easily dissolve in water and we found as most appropriate the polymer produced from the cypress tree,” explains Dr. Yoav Livney of the Technion’s Faculty of Biotechnology and Food Engineering and the Russell Berrie Nanotechnology Institute. “The cancerous cell produces receptors that absorb the folic acid in much larger quantities than the healthy cell. The cancerous cell needs this acid in order to divide quickly and grow,” adds Dr. Livney. “After the folic acid connects to the receptor, a process, called endocytosis, is renewed. This is a process in which the cell membrane peels inward creating a depression that turns into a bubble called an endosome. It unites with another bubble called a lysosome, which contains enzymes that digest the contents of the bubbles (a kind of cell digestive system). When the PH measure decreases, the receptor releases the folic acid.”

Technion scientists Prof. Yehuda Assaraf from the Faculty of Biology and Dr. Livney attach the drug to a polysugar by a section of protein (peptide) that is dissolved by the enzymes secreted by the lysosome. The drug is released only in the lysosome because there are no enzymes in the blood that know how to break down this specific peptide.

The Technion development is especially efficient against ovarian, kidney and uterine cancer, which is characterized by folic acid receptors.