Photodynamic therapy (PDT) is used to treat solid cancers such as skin, pancreatic and cervical cancers. It destroys cancer cells when patients receive an intravenous injection of certain chemicals known as photosensitizing agents. However, when the medication is exposed to the sunlight, it activates and causes a reaction. Until now, patients have had to stay in the dark room for a month to shun the light when receiving the PDT
The Ministry of Science, ICT and Future Planning (MSIP) announced on September 7 that Korean scientists succeeded in developing “temperature-responsive smart photosensitizing agent” that can improve problems caused by side effects, including the sunlight, and enhance the cancer-fighting effect.
Professor Nah Gun of the Catholic University of Korea and his researchers and Professor Kim Dong-hyun of Northwestern University Medical School combined hydroxypropyl cellulose, a polymer polysaccharide substance which is used to produce drugs due to its good biocompatibility and thermo-sensitivity, with existing unimolecular photosensitizers. The new temperature-responsive smart photosensitizing agent is not activated by light at the normal body temperature of 37 degrees Celsius but is activated at the temperature of 45 degrees Celsius in the thermal cancer treatment with a proven efficacy against cancers.
There is a low possibility of side effects since it is not activated even when exposed to the sunlight unless the temperature goes up to the temperature of 45 degrees Celsius. In other words, the temperature can reach the certain point through the thermal cancer treatment, allowing two different kinds of therapies at the same time.
Professor Nah Gun said, “With the latest achievement, the new photosensitizing agents can be used not only in existing PDT but also as the base technology to apply to the development of bio temperature sensors. It is also very meaningful in that it is a successful example of multidisciplinary joint research between Korea and the U.S. through various scientific technology exchanges.” The research was part of the MSIP’s basic research project. The study was posted on the online edition of the Journal of The American Chemical Society, an international scientific journal in the chemistry sector, August 18.