14 DAY TRIAL // Shutting down malfunctioning genes, such as those that contribute to the development of cancer, would be an excellent way to destroy the condition from its roots, but experts have no efficient way of doing that. Or, at least, that was the case until recently.
A group of scientists based at the Massachusetts Institute of Technology (MIT), in Cambridge, believes that a type of therapy called RNA interference may become possible in the immediate future. This approach works by delivering short snippets of ribonucleic acid to genes that operate abnormally.
These snippets of genetic code tell the gene or genes in question to shut down. If experts could deliver RNA inside cancer cells, the genetic data would make short work of some of the most stubborn tumors currently known to science.
However, RNA interference is very difficult to perform in practice, primarily because it relies on short interfering RNA (siRNA), tiny bits of code that are always attacked by the body's protective enzymes.
The molecules believe that siRNA belongs to RNA viruses, a dangerous class of pathogens, and so prefer to err on the side of caution and break the foreign code apart. Unfortunately, this is one instance in which their behavior does more harm than good.
What the MIT team did in the new study was provide a new means of transportation for the siRNA, one that does not fall prey to the destructive power of enzymes. The work was led by the MIT David H. Koch Professor in Engineering, Paula Hammond.
“It’s been a real struggle to try to design a delivery system that allows us to administer siRNA, especially if you want to target it to a specific part of the body,” she says. The expert explains that folding the genetic material very tightly can result in the formation of so-called microspheres.
Due to this arrangement, the tiny spheres are very dense, and can therefore withstand enzyme attacks successfully, at least until they reach their destination. Details of the research effort appear in the February 26 issue of the top scientific journal Nature Materials.
In the near future, the MIT team plans to create a method of coating the siRNA microspheres with special polymers, which would further increase the structures' affinity for tumor cells. Additionally, subsequent tweaks may lead to the constructs being able to target other diseased cells as well.