Story URL: http://news.medill.northwestern.edu/chicago/news.aspx?id=165132
Story Retrieval Date: 5/25/2013 12:05:13 PM CST
Nanotechnology may offer the next frontier in treating cancer with greater success and fewer side effects.
Though treatments may be several years away, a recent study highlights the possibilities for innovative treatments in the field.
Researchers at the California Institute of Technology successfully used nanoparticles, tiny particles that can package treatments, to target cancerous cells and attack them with a process known as RNA interference, according to a study published in a recent online edition of the journal Nature.
The research demonstrates for the first time that nanoparticles designed to seek out a certain kind of cell would reach their target, said Mark Davis, a Caltech professor of chemical engineering and a lead study author.
Researchers observed that increasing doses of nanoparticles equated to higher levels of the nanoparticle delivery observed in tumors.
“It’s the first demonstration of a nanoparticle therapeutic administered into the bloodstream of patients,” said Dr. Shad Thaxton, a professor of urology at Northwestern, “And, importantly, they’ve shown that it works through the mechanism that it should work, which is a very impressive achievement.”
He said that he views nanoparticles on the front lines in the future of medicine.
“Nanoparticle therapeutics that are currently in the evaluation stages are anywhere from five to 10 years from being used as standard first line therapeutic agents,” said Thaxton. He said that other nanoparticle therapies that are in earlier phases of research are closer to seven to 15 years from entering human trials and FDA approval.
Jonathan Widom, a professor of biochemistry at Northwestern University, described the study as bringing together existing areas of science – nanotechnology and RNA interference - and demonstrating their practical applications.
“What is special about it is it demonstrates the approach is technically feasible,” he said.
Widom said that in the previous decade, scientists thought that the DNA of a cell should be targeted in cancer treatment, but more recent research showed that RNA should be the therapy target. RNA is a single-stranded molecule similar to DNA that is critical in forming proteins and proteins are customized to the activities of specific cells in the body.
RNA interference makes it possible to selectively alter or delete the functions of these proteins. Cancer involves abnormal protein activity that can be interrupted by this process. Davis said that this study provided the first direct evidence that RNA interference can work in humans.
“One of the major hurdles in the field is how do you get the RNA there,” said Davis. The RNA used is unstable and prone to degradation, but in this case, the use of a nanoparticle delivery system allowed the RNA to remain stable and act on tumor cells.
RNA interference holds promise for other conditions. Widom described it as applicable to any disease where protein activity is abnormal, which is the case in cancer. He said adjusting RNA is “hugely, broadly applicable and that is part of the importance”
“The selectivity of treatment can be very high,” said Davis, adding that “there are many different avenues that you could do.”
Davis said that in traditional drug therapies, the functions of proteins must be targeted, which can be difficult or even impossible in some case. RNA can affect proteins independently of their functions. The possibilities that this raises, include the ability to slow degenerative diseases, or treat pain without painkillers that impair a patient’s activity, according to Davis.
“Now you can attack various genes and those proteins that were undruggable by other methods,” said Davis.
While the treatment shows promise, broader application of the treatment could still be far off. Davis said that there is “no good answer” in cancer research for when treatments can be predicted to become implemented widely.
Even once treatemnts are developed, testing and approval involves years of clinical trials.