ETA2024 Poster Presentations Translational thyroid cancer research-2 (10 abstracts)
1Institute for the Application of Nuclear Energy - Inep, Department for Endocrinology and Radioimmunology, Belgrade, Serbia; 2Institute for the Application of Nuclear Energy Inep, Department for Endocrinology and Radioimmunology, University of Belgrade, Institute for the Application of Nuclear Energy Inep, University of Belgrade, Belgrade, Serbia, Institute for the Application of Nuclear Energy Inep, University of Belgrade, Belgrade, Serbia, Belgrade, Serbia; 3Institute for the Application of Nuclear Eenergy - Inep, Departmant for Endocrinology and Radioimmunology, Belgrade, Serbia; 4Institute for the Application of Nuclear Energy Inep, University of Belgrade, Institute for the Application of Nuclear Energy, Department for Endocrinology and Radioimmunology, Belgrade, Serbia; 5Clinical Center of Serbia, Clinic for Endocrine Surgery, Belgrade, Serbia; 6Clinical Center of Serbia, Department of Pathology, Belgrade, Serbia; 7Institute for the Application of Nuclear Energy Inep, University of Belgrade, Belgrade, Serbia, Institute for the Application of Nuclear Energy, Departmant for Endocrinology and Radioimmunology, Belgrade, Serbia
Objectives: ETS-1 (E26 transformation-specific) is a transcription factor associated with the progression of carcinomas of various origins. Its expression in PTC is poorly described, and the findings are controversial. This study aimed to describe ETS-1 protein expression in papillary thyroid carcinoma (PTC) and to evaluate the potential influence of miR-204-3p on the ETS-1 protein expression in PTC since the bioinformatic analysis revealed that miR-204-3p shares a seed sequence with the 3-untranslated region (3UTR) of ETS-1 mRNA.
Methods: Immunohistochemistry was performed to evaluate ETS-1 protein expression in 77 routinely prepared archival tissue sections of PTC, of which 55 had surrounding nonmalignant thyroid tissue (NMT). Quantitative RT-PCR (qPCR) was utilized to quantify ETS-1 mRNA and miR-204-3p levels of expression in matched snap-frozen PTC and adjacent NMT.
Results: In the immunohistochemical examination, 76 out of 77 PTC samples displayed positive staining for ETS-1 protein, observed in either the nucleus or the cytoplasm, or in both. Conversely, among 55 NMT, ETS-1 protein exhibited positive staining in 39 samples, found predominantly in the nucleus. Considering the total IHC score, there was an increase in ETS-1 protein expression in PTC compared to the surrounding tissue (P < 0.05). However, there was no difference in its mRNA levels between PTC and matched NMT (P > 0.05). The levels of miR-204-3p expression showed lower values in PTC compared to their levels in paired NMT (P < 0.05). Furthermore, the complementary binding between miR-204-3p and ETS-1 mRNA was predicted by bioinformatic analysis and model prediction. Therefore, decreased levels of miR-204-3p in PTC may be the cause of elevated levels of ETS-1 protein, contributing to PTC progression.
Conclusions: ETS-1 mRNA may have been complementarily bound by miR-204-3p in thyroid tissue, which may result in down-regulated ETS-1 protein levels.