TY - JOUR
T1 - A novel therapeutic strategy for medullary thyroid cancer based on radioiodine therapy following tissue-specific sodium iodide symporter gene expression
AU - Cengic, Neziha
AU - Baker, Claire H.
AU - Schütz, Martin
AU - Göke, Burkhard
AU - Morris, John C.
AU - Spitzweg, Christine
PY - 2005/8
Y1 - 2005/8
N2 - Context: In contrast to papillary and follicular thyroid cancer, medullary thyroid cancer (MTC) remains difficult to treat due to its unresponsiveness to radioiodine therapy and its limited responsiveness to chemo- and radiotherapy. Objective: To investigate an alternative therapeutic approach, we examined the feasibility of radioiodine therapy of MTC after human sodium iodide symporter (hNIS) gene transfer using the calcitonin promoter to target hNIS gene expression to MTC cells (TT). Design: TT cells were stably transfected with an expression vector, in which hNIS cDNA was coupled to the calcitonin promoter. Functional hNIS expression was confirmed by iodide accumulation assays, Northern and Western blot analysis, immunostaining, and in vitro clonogenic assay. Results: hNIS-transfected TT cells showed perchlorate-sensitive iodide uptake, accumulating 125-I about 12-fold in vitro with organification of 4% of accumulated iodide resulting in a significant decrease in iodide efflux. NIS protein expression was confirmed by Western blot analysis using a monoclonal hNIS-specific antibody, which revealed a major band of a molecular mass of 80-90 kDa. In addition, immunostaining of hNIS-transfected TT cells revealed hNIS-specific immunoreactivity, which was primarily membrane associated. In an in vitro clonogenic assay, 84% of NIS-transfected TT cells were killed by exposure to 131-I, whereas only about 0.6% of control cells were killed. Conclusions: A therapeutic effect of 131-I has been demonstrated in MTC cells after induction of tissue-specific iodide uptake activity by calcitonin promoter-directed hNIS expression. This study demonstrates the potential of NIS as a therapeutic gene, allowing radioiodine therapy of MTC after tissue-specific NIS gene transfer.
AB - Context: In contrast to papillary and follicular thyroid cancer, medullary thyroid cancer (MTC) remains difficult to treat due to its unresponsiveness to radioiodine therapy and its limited responsiveness to chemo- and radiotherapy. Objective: To investigate an alternative therapeutic approach, we examined the feasibility of radioiodine therapy of MTC after human sodium iodide symporter (hNIS) gene transfer using the calcitonin promoter to target hNIS gene expression to MTC cells (TT). Design: TT cells were stably transfected with an expression vector, in which hNIS cDNA was coupled to the calcitonin promoter. Functional hNIS expression was confirmed by iodide accumulation assays, Northern and Western blot analysis, immunostaining, and in vitro clonogenic assay. Results: hNIS-transfected TT cells showed perchlorate-sensitive iodide uptake, accumulating 125-I about 12-fold in vitro with organification of 4% of accumulated iodide resulting in a significant decrease in iodide efflux. NIS protein expression was confirmed by Western blot analysis using a monoclonal hNIS-specific antibody, which revealed a major band of a molecular mass of 80-90 kDa. In addition, immunostaining of hNIS-transfected TT cells revealed hNIS-specific immunoreactivity, which was primarily membrane associated. In an in vitro clonogenic assay, 84% of NIS-transfected TT cells were killed by exposure to 131-I, whereas only about 0.6% of control cells were killed. Conclusions: A therapeutic effect of 131-I has been demonstrated in MTC cells after induction of tissue-specific iodide uptake activity by calcitonin promoter-directed hNIS expression. This study demonstrates the potential of NIS as a therapeutic gene, allowing radioiodine therapy of MTC after tissue-specific NIS gene transfer.
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U2 - 10.1210/jc.2004-2140
DO - 10.1210/jc.2004-2140
M3 - Article
C2 - 15941870
AN - SCOPUS:23844522829
SN - 0021-972X
VL - 90
SP - 4457
EP - 4464
JO - Journal of Clinical Endocrinology and Metabolism
JF - Journal of Clinical Endocrinology and Metabolism
IS - 8
ER -