Sodium Iodide Symporter for Nuclear Molecular Imaging and Gene Therapy: From Bedside to Bench and Back

Abstract

Molecular imaging, defined as the visual representation, characterization and quantification of biological processes at the cellular and subcellular levels within intact living organisms, can be obtained by various imaging technologies, including nuclear imaging methods. Imaging of normal thyroid tissue and differentiated thyroid cancer, and treatment of thyroid cancer with radioiodine rely on the expression of the sodium iodide symporter (NIS) in these cells. NIS is an intrinsic membrane protein with 13 transmembrane domains and it takes up iodide into the cytosol from the extracellular fluid. By transferring NIS function to various cells via gene transfer, the cells can be visualized with gamma or positron emitting radioisotopes such as Tc-99m, I-123, I-131, I-124 and F-18 tetrafluoroborate, which are accumulated by NIS. They can also be treated with beta- or alpha-emitting radionuclides, such as I-131, Re-186, Re-188 and At-211, which are also accumulated by NIS. This article demonstrates the diagnostic and therapeutic applications of NIS as a radionuclide-based reporter gene for trafficking cells and a therapeutic gene for treating cancers.

Uptake and Cytotoxicity Characterization of Radioiodine in MCF-7 and SKBR3 Breast Cancer Cell Lines

“…This is due to its ability to increase the rate of patient survival compared to patients who do not receive I-131 [3,4]. This therapy is based on the uptake of radioiodine into cancer cells.…”

“…This therapy is based on the uptake of radioiodine into cancer cells. In thyroid cancer, the uptake of I-131 is affected by the natrium/iodide symporter (NIS) expression [3,5,6]. A natrium/iodide symporter brings two sodium ions (Na + ) and one iodide ion (I -) to cross the membrane against its ionic concentration gradient [3,6,7].…”

Transfection with Sodium Iodine Symporter Gene (NIS) and Future Applications with Radioiodine Treatment

“…It has been known that non thyroidal tissues also express NIS however only small part of these NIS expressing tumors do show iodine uptake [20]. The NIS expression in other tissues than thyroid tissue like salivary glands, gastric mucosa and mammary gland are lower than thyroid tissue [21]. Additionally it has been observed that malign breast tissue as well as benign breast tissue may retain iodine and thus the first applications cover breast cancer with NIS transfection [9].…”

Use of Nuclear Medicine Technology for Clinical Molecular Imaging: a Message from the Associate Editor

“…Molecular imaging is defined as the visual representation, characterization, and quantification of biological processes at the cellular and subcellular levels within intact living organisms; this can be achieved by various imaging technologies such as nuclear imaging, optical imaging, magnetic resonance imaging (MRI), ultrasound imaging, and computed tomography (CT) [1]. Although these modalities are actively used for sensing molecular and cellular processes in preclinical studies, the majority of imaging techniques remain unapplied in the clinical field due to various unresolved issues, such as safety, poor tissue penetration of the imaging signal, and limited sensitivity.…”

“…Although these modalities are actively used for sensing molecular and cellular processes in preclinical studies, the majority of imaging techniques remain unapplied in the clinical field due to various unresolved issues, such as safety, poor tissue penetration of the imaging signal, and limited sensitivity. So far, nuclear or fusion imaging modalities with the nuclear medicine component are the actively used molecular imaging modalities in the clinical field [1][2][3].…”