PHILADELPHIA (October 24, 2000) -- Radiation treatment for prostate cancer is more effective in tumor cells in which the DNA is structurally compact. That is the result of a new study that was presented at the American Society for Therapeutic Radiology and Oncology Annual Meeting in Boston, Mass. on Tuesday, October 24, at 11:45 a.m.
In the study completed at Fox Chase Cancer Center, human prostate cancer cells were irradiated in tissue culture and the survival measured by clonogenic assays. The degree of compaction of the chromatin was chemically altered by okadaic acid (OA), fostriecin (FC) and tricostatin A (TSA). Both electron microscopy and flourescence confocal microscopy were used to measure the compaction of the chromatin in interphase cells.
Microscopy examination of irradiated drug-treated cells showed a significant increase in molecular compaction. Radiation survival studies of the tumor cells after adding FC and TSA show that the cells were significantly radiosensitized and thus were more susceptible to irradiation.
"These data suggest that there is a direct correlation between irradiation and the compaction status of chromatin in tumor cells," explained Jim Wurzer, M.D., the author of the study. "In addition, information from these data may allow physicians to examine a biopsy specimen and predict the radiosensitivity of cells in individual cancers. In the future, we may be able to use chemical agents to manipulate the cells in tumors to make them more sensitive to treatment."
Fox Chase Cancer Center, one of the nation's first comprehensive cancer centers designated by the National Cancer Institute in 1974, conducts basic and clinical research; programs of prevention, detection and treatment of cancer; and community outreach. For more information about Fox Chase activities, visit the Center's web site at www.fccc.edu.
Abstract # 120 DNA Compaction and Radiation-induced Cell Killing in Human Prostate Cancer Cells to be presented Oct. 24, 2000, 11:45 a.m. (Dr. Jim Wurzer was a research fellow in the Department of Radiation Oncology at Fox Chase Cancer Center and now practices at Atlantic City Medical Center in Pomona, New Jersey.)