Retinoid receptors (RARs) upon a proper ligand binding act as all-trans retinoic acid-inducible transcription factors interacting as heterodimers with retinoid X receptors (RXRs). Predominantly, novel synthetic retinoid analogues acting through RARs as redifferentiation agents would be of great value in treating patients with advanced thyroid cancer.
The objective of this study was to investigate all-trans retinoic acid/9-cis retinoic acid nuclear receptor subtypes (RARalpha, RARbeta, RARgamma, RXRalpha, RXRbeta, RXRgamma) expression pattern in papillary thyroid tumour tissue of patients in order to compare it with that of anaplastic thyroid carcinoma and the intact thyroid tissue of the corresponding patients. The expression of the retinoid/rexinoid nuclear receptor subtypes has been analyzed by the RT-PCR technique.
The data has shown that papillary thyroid carcinoma of investigated patients expressed all subtypes of RARs and RXRs when compared to intact thyroid tissues of the corresponding patients that were lacking to express RXRgamma. In papillary thyroid carcinoma, expression of RXRgamma was enhanced in comparison with that of RXRalpha or RXRbeta. Expression of RXRgamma in the patient with anaplastic carcinoma was found to be lower than that of in patients with papillary carcinoma.
In conclusion, this type of diagnostic approaches enlisted into the diagnostic algorithm of patients before their possible treatment with retinoic acids or retinoid analogues might thus enhance therapeutical potentialities and bring positive results in the treatment of thyroid cancer.
Supported by the grant APVV-0120-07 and the VEGA grant 2/0022/08.
25 - 29 Apr 2009
European Society of Endocrinology