Expression of NIS Protein and mRNA in Thyroid Tumors

The safety and scientific validity of this study is the responsibility of the study sponsor and investigators. Listing a study does not mean it has been evaluated by the U.S. Federal Government. Read our disclaimer for details. Identifier: NCT00459498
Recruitment Status : Completed
First Posted : April 12, 2007
Last Update Posted : April 12, 2007
Fundação de Amparo à Pesquisa do Estado de São Paulo
Information provided by:
University of Sao Paulo

Brief Summary:
The uptake of iodide by thyroid cells requires the expression of sodium iodide symporter (NIS). Thyroid benign and malignant tumors have low iodide uptake activity. Previous studies of NIS expression with RT-PCR and immunohistochemistry showed divergent data. NIS protein was overexpressed in thyroid cancer. The aim of this study was to investigate the NIS transcript levels and its presence and localization in 30 samples of thyroid tumors (14 benign and 16 malignant) and in their surrounding non-tumoral tissues (NT), by real time RT-PCR and immunohistochemistry, respectively. Our results revealed lower gene expression in 78.6% of the benign tumors and 100% of the carcinomas when compared with the NT samples, using GHPDH as a housekeeping gene. Immunohistochemical staining revealed presence of NIS protein in 100% of the non-tumoral samples, 100% of the benign tumors and 93.75% of the malignant tumors. NIS protein was identified at basolateral membrane in 23.3% of non-tumoral samples, 14.3% of benign and 12.5% of malignant tumors. Stronger cytoplasmatic immunostaining of NIS protein was detected in 64.3% of benign tumors and in 87.5% of malignant tumors when compared to NT. Association between low gene expression and strong cytoplasmatic immunostaining was found in 50% of benign tumors and 87.5% of malignant tumors. We concluded that the reduced NIS gene expression in thyroid tumors associated with strong intracytoplasmatic staining may be due to its incapacity to migrate to cellular membrane.

Condition or disease

Detailed Description:
The aim of this study was to quantify NIS transcript levels by real time PCR and to determine the presence and cellular localization of NIS protein by immunohistochemistry, in benign and malignant thyroid tumor cells and to compare with their paired surrounding non-tumoral cell. NIS expression was also compared to that of the TSHR

Study Type : Observational
Enrollment : 30 participants
Primary Purpose: Screening
Time Perspective: Cross-Sectional
Time Perspective: Prospective
Official Title: Significant Intracellular NIS Protein Associated With Low Levels of NIS Messenger RNA in Malignant Thyroid Tumors
Study Start Date : April 2002
Actual Study Completion Date : October 2006

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Drug Information available for: Thyroid
U.S. FDA Resources

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Ages Eligible for Study:   18 Years to 80 Years   (Adult, Senior)
Sexes Eligible for Study:   All
Accepts Healthy Volunteers:   No

Inclusion Criteria:

  • PAtients with thyroid tumors undergoing surgery for total or partial thyroidectomy

Exclusion Criteria:

  • Pregnancy

Information from the National Library of Medicine

To learn more about this study, you or your doctor may contact the study research staff using the contact information provided by the sponsor.

Please refer to this study by its identifier (NCT number): NCT00459498

Sponsors and Collaborators
University of Sao Paulo
Fundação de Amparo à Pesquisa do Estado de São Paulo
Principal Investigator: Ana K Sodré University of São Paulo
Study Director: Rosalinda Y Camargo University of São Paulo

Publications: Identifier: NCT00459498     History of Changes
Other Study ID Numbers: PRN736/02
First Posted: April 12, 2007    Key Record Dates
Last Update Posted: April 12, 2007
Last Verified: April 2007

Keywords provided by University of Sao Paulo:
thyroid adenoma
thyroid cancer
Iodine uptake

Additional relevant MeSH terms:
Thyroid Neoplasms
Endocrine Gland Neoplasms
Neoplasms by Site
Head and Neck Neoplasms
Endocrine System Diseases
Thyroid Diseases