Spicing Up Radiation Therapy
October 28, 2010 | Melissa Marino
Natural compounds derived from spices such as cinnamon and turmeric may sensitize tumors to radiation therapy, according to a report in the Oct. 15 issue of Bioorganic & Medicinal Chemistry Letters
Heat shock, one of the most effective radiosensitizers, induces a “proteotoxic stress” that initiates a series of events leading to cell death. Because of the technical difficulties of inducing hyperthermia clinically, Sekhar Konjeti, Ph.D., Michael Freeman, Ph.D., and colleagues have been searching for and synthesizing compounds that mimic this effect and enhance radiosensitivity at physiological temperatures.
The investigators identified two natural compounds (hydroxychalcones called D-501 and D-601) and found that both induce “heat shock” and enhance radiation-induced death in cultured colon and pancreatic cancer cells. An inhibitor of cytochrome P450 (an enzyme involved in drug metabolism) blocked the radiosensitizing effect of D-601, suggesting that a metabolite mediates the radiosensitization.
Although future studies are needed to identify this metabolite, these findings offer new leads for developing novel radiosensitizing agents from natural products.
For other research highlights from Vanderbilt University Medical Center laboratories, see ‘Aliquots‘ in the VUMC Reporter.