1. ¹Department of Physiology and Cell Biology, College of Medicine and Public Health, The Ohio State University, Columbus, OH, USA
2. ²Department of Pathology, College of Medicine and Public Health, The Ohio State University, Columbus, OH, USA
3. ³Department of Radiology, College of Medicine and Public Health, The Ohio State University, Columbus, OH, USA
4. ⁴Department of Statistics, College of Medicine and Public Health, The Ohio State University, Columbus, OH, USA
5. ⁵Department of Internal Medicine, College of Medicine and Public Health, The Ohio State University, Columbus, OH, USA
6. ⁶Department of Nuclear Medicine, Tri-Service General Hospital, National Defense Medical Center, Taipei, ROC

Correspondence: Dr SM Jhiang, Department of Physiology and Cell Biology, The Ohio State University, 304 Hamilton Hall, 1645 Neil Avenue, Columbus, OH 43210-1218, USA

Received 14 April 2003; Accepted 25 July 2003.

Abstract

The sodium iodide symporter (NIS) mediates iodide uptake into thyrocytes and is the molecular basis of thyroid radioiodine therapy. We previously have shown that NIS gene transfer into the F98 rat gliomas facilitated tumor imaging and increased survival by radioiodine. In this study, we show that: (1) the therapeutic effectiveness of ¹³¹I in prolonging the survival time of rats bearing F98/hNIS gliomas is dose- and treatment-time-dependent; (2) the number of remaining NIS-expressing tumor cells decreased greatly in RG2/hNIS gliomas post ¹³¹I treatment and was inversely related to survival time; (3) 8 mCi each of ¹²⁵I/¹³¹I is as effective as 16 mCi ¹³¹I alone, despite a smaller tumor absorbed dose; (4) ¹⁸⁸ReO₄, a potent ^- emitter, is more efficient than ¹³¹I to enhance the survival of rats bearing F98/hNIS gliomas. These studies demonstrate the importance of radiopharmaceutical selection, dose, and timing of treatment to optimize the therapeutic effectiveness of NIS-targeted radionuclide therapy following gene transfer into gliomas.