|Heated iron oxide nanoparticles release cancer drugs and kill ovarian cancer cells.--Courtesy of Oregon State University|
A new study out of Oregon State University has shown that a combination of mild heat and nanoparticle-delivered chemotherapy can have a whopping effect on ovarian cancer cells that have otherwise built up a resistance to cancer drugs.
In work reported in the International Journal of Pharmaceutics, researchers used iron oxide nanoparticles coated with the chemotherapeutic agent doxorubicin and heated the compound once it was embedded in cancer cells, noting that it killed up to 95% of them in early lab tests, with room to improve, the scientists hope. The nanoparticle aspect of the method gets around the difficulty of heating just the cancer cells, as opposed to surrounding ones, by targeting them first with a peptide and then heating the particles with the use of a magnetic field.
Scientists have used heat successfully before to combat cancer, but this specific marriage of targeted particles and higher temperatures gave the treatment an extra punch. According to a report from the university, a modest dose of the drug combined with temperatures of about 104 degrees was far more effective than either treatment would be alone. The drug normally leaves about 70% of cancer cells alive.
Furthermore, a polyethylene glycol coating gave the particles more targeting capability and enhanced their "stealth" action in the bloodstream.
"I'm very excited about this delivery system," OSU researcher Oleh Taratula said in a statement. "Cancer is always difficult to treat, and this should allow us to use lower levels of the toxic chemotherapeutic drugs, minimize side effects and the development of drug resistance, and still improve the efficacy of the treatment. We're not trying to kill the cell with heat, but using it to improve the function of the drug."