phosphocreatine and Melanoma--Amelanotic

Inadequate tumor reoxygenation during radiation therapy may cause local treatment failure. This study was aimed at investigating the potential usefulness of 31P-MRS in monitoring tumor reoxygenation following radiation treatment.. Tumors of two human melanoma xenograft lines (BEX-t and HUX-t) were exposed to 15.0 Gy, and then the fraction of radiobiologically hypoxic cells, measured by using the paired survival curve method, or tumor bioenergetic status, measured by 31P-MRS as the (PCr + NTPbeta)/Pi resonance ratio, was determined versus time after the radiation exposure.. Untreated BEX-t and HUX-t tumors showed similar fractions of radiobiologically hypoxic cells and similar bioenergetic status, whereas both parameters differed substantially between the lines in irradiated tumors. A close association was found between radiation-induced changes in tumor bioenergetic status and radiation-induced changes in the fraction of radiobiologically hypoxic cells.. 31P-MRS is a potentially useful method for monitoring tumor reoxygenation following radiation treatment.

Topics: Animals; Cell Death; Cell Hypoxia; Cell Survival; Energy Metabolism; Humans; Magnetic Resonance Spectroscopy; Male; Melanoma, Amelanotic; Mice; Mice, Inbred BALB C; Mice, Nude; Monitoring, Physiologic; Neoplasm Transplantation; Oxygen Consumption; Phosphates; Phosphocreatine; Phosphorus Isotopes; Radiotherapy Dosage; Transplantation, Heterologous; Treatment Failure; Tumor Cells, Cultured