Researchers from McGill University have discovered a way to deliver cancer drugs to damaged cells, nanoscale cages, so that patients who otherwise couldn’t have been helped in the past now can be. DNA strands are used to create these nanoscale cages, which can be designed to release cancer drugs in response to a selected stimulus.
The study was published by the researchers on September 1 in Nature Chemistry, an online journal.
How are the DNA-strand nanascale cages created?
The researchers created nanocubes with short DNA strands which they modified through the use of molecules that are similar to lipids. Then, an inner recess or “hold” which could carry within them hydrophobic molecules of cancer drugs, was created. If the DNA cubes had the sticky patches or lipids applied to their outer faces, the researchers noted that the cubes would stick together.
The resultant nanoscale cages can be designed to carry the cancer drugs to specific areas in a person’s body. The drugs would be released when the DNA strands, or tentacles, carrying the drugs fall off upon reaching the specific programmed location where they’re the most needed.
The DNA cages used to deliver drugs can be made in a vast variety of shapes.
In the words of Hanadi Sleiman, who headed up the research team:
We are able to create DNA cages with any geometry, size or shape, and that’s unique among drug delivery vehicles. They are extremely programmable.”
The McGill University study marks the first time that molecules which don’t stick to DNA have been carried inside the nanoscale cages.
A fluorescing molecule known as “Nile Red,” was the one which was used the most in the study. It’s fluorescence allowed the researchers to show how the nanoscale cages carry cancer drugs. The research team also used dasatinib. It’s a drug which is often used as a leukemia treatment. The researchers discovered that dasatinib “retained elevated amounts” of the drug in comparison to controls.
By “cutting off the chains,” as a team of researchers in 2000 did from the University of Toronto and Bell Labs, the molecules carrying the drugs were released.
This “cutting off” occurs when a new DNA strand affixes itself to the cube instead of to the chains. This acts to displace the chains, or “cut them off.”
The research, so far, has only taken place inside of test tubes. According to Sleiman, research into DNA nanoscale cages was only began a few years ago.
Sleiman notes that: “It’s just the beginning. To be a powerful drug delivery system you need the release to happen inside or on the cell. That’s going to be the next hurdle.”
The creation of DNA nanoscale cages might prove to be the method doctors in the coming years use to deliver cancer drugs, or other drugs, to areas of a person’s body where they can be the most beneficial.
Written by: Douglas Cobb