Searchable abstracts of presentations at key conferences in endocrinology

ea0035p1142 | Thyroid Cancer | ECE2014

Polymorphic pre-miR-146a and synergistic action of all of its products on NTRK2 gene in papillary thyroid carcinoma

Kubiak Anna , Wojcicka Anna , Wiechno Wieslaw , Niewinski Grzegorz , Jazdzewski Krystian

Objectives: Aberrances in expression and sequence of miR-146a have a well-established role in pathogenesis of papillary thyroid carcinoma (PTC). The G/C heterozygosity in rs2910164 of miR-146a underlies genetic predisposition to PTC and occurs as a somatic mutation in thyroid tumors. Deleterious function of rs2910164 consists in creation of a new variant of microRNA, resulting from the fact that a single microRNA precursor gives rise to −5p and −3p microRNAs. The S...

ea0035p1121 | Thyroid Cancer | ECE2014

The role of microRNAs in regulation of RARβ and its function in development of papillary thyroid carcinoma

Czajka Agnieszka , Wojcicka Anna , Stachlewska Elzbieta , Wiechno Wieslaw , Niewinski Grzegorz , Jazdzewski Krystian

Objectives: Papillary thyroid carcinoma (PTC) exhibits aberrant expression of retinoic acid receptor β (RARβ), a retinoic acid-inducible transcription factor, essential for cellular growth and development. The mechanisms leading to decreased RARβ expression in tumors are unknown. We hypothesized that changes in expression of RARB, a gene encoding for RARβ, result from aberrant expression of microRNAs. We elucidated the miRNome of normal thyroid and...

ea0035p1123 | Thyroid Cancer | ECE2014

Sodium–iodide symporter and its microRNA-dependent deregulation in papillary thyroid carcinoma.

Kotlarek Marta , Gierlikowski Wojciech , Kubiak Anna , Maciag Monika , Jazdzewski Krystian , Wojcicka Anna

Objectives: The sodium/iodide symporter (NIS) is a glycoprotein with unique ability of transporting iodine into the thyroid follicle. Apart from the importance in thyroid hormone synthesis, this function of NIS allows the use of radioactive iodine to target residual and metastatic thyroid cancer after thyroidectomy. However, 20–30% of thyroid tumors exhibit lowered expression of NIS, resulting in decreased uptake of radioiodine and inefficient post-surgical therapy. Mecha...

ea0035p1125 | Thyroid Cancer | ECE2014

Apical iodide transporter and its microRNA-induced silencing in thyroid malignancies

Gierlikowski Wojciech , Kotlarek Marta , Bakula-Zalewska Elwira , Jazdzewski Krystian , Wojcicka Anna

Objectives: Apical iodide transporter (AIT) is essential for thyroid homeostasis, functioning both as iodide transporter and a potent tumor suppressor. Its decreased levels observed in thyroid cancer underlie its progression and inefficiency of radioactive iodine treatment, used for ablation of post-operative and metastatic thyroid cancer cells. Mechanisms of AIT downregulation in cancer are largely unknown, but recent data on overexpression of microRNAs in thyroid cancer sugg...

ea0035p1128 | Thyroid Cancer | ECE2014

Next-generation sequencing reveals a novel thyroglobulin-embedded microRNA gene deregulated in papillary thyroid carcinoma

Kolanowska Monika , Wojcicka Anna , Kubiak Anna , Swierniak Michal , Maciag Monika , Wiechno Wieslaw , Jazdzewski Krystian

Introduction: Papillary Thyroid Carcinoma (PTC) exhibits activation of MAPK (Mitogen-activated protein kinases) pathway, leading to uncontrolled cellular division and growth. Concomitantly, thyroid tumors exhibit aberrant expression of numerous microRNAs, which are non-coding RNAs that inhibit expression of protein-coding genes. Employing next-generation sequencing (NGS), we revealed comprehensive miRNA profiles of normal thyroid and PTC, and identified putative novel microRNA...

ea0022p431 | Endocrine tumours &amp; neoplasia (<emphasis role="italic">Generously supported by Novartis</emphasis>) | ECE2010

The Role of miRNA in reduction of type I 5’-iodothyronine deiodinase expression (D1) in renal clear cell carcinoma (ccRCC)

Boguslawska Joanna , Master Adam , Wojcicka Anna , Poplawski Piotr , Piekielko-Witkowska Agnieszka , Nauman Alicja

Type 1 deiodinase (D1) catalyses deiodination of tyroxine (T4), which leads either to synthesis of triiodothyronine or reverse triiodothyronine (rT3). Triiodothyronine (T3) regulates the expression of many tumour suppressor genes and oncogenes. We previously revealed that the expression of the whole pool of D1 transcripts was dramatically lowered in ccRCC tissues. One of the mechanism resulting in this aberration could be miRNA-mediated repress...

ea0090p28 | Calcium and Bone | ECE2023

Clinical application of vitamin D metabolites measurement using LC-MS/MS – a case of a patient with persistent hypercalcemia and two pathogenic mutations in CYP24A1 gene and parathyroid adenoma

Leszczynska Dorota , Szatko Alicja , Latocha Julia , Kochman Magdalena , Duchnowska Maria , Wojcicka Anna , Misiorowski Waldemar , Zgliczyński Wojciech , Glinicki Piotr

Introduction: 24-hydroxylase, encoded by a CYP24A1 gene, is a crucial enzyme entailed in catabolism of vitamin D. Loss-of-function mutations of CYP24A1 result in hypercalcemia, not adequately concomitant high levels of 1,25(OH)2D and low PTH levels. The variety of clinical manifestations depends on age – mutations can lead to fatal infantile hypercalcemia among neonates (typically precipitated by supplementation of vitamin D), whereas adults’ symptoms are usually mil...

ea0035p1129 | Thyroid Cancer | ECE2014

The role of ATM–CHEK2–BRCA1 axis in determination of genetic predisposition and clinical presentation of papillary thyroid carcinoma

Wojcicka Anna , Czetwertynska Malgorzata , Swierniak Michal , Dlugosinska Joanna , Maciag Monika , Czajka Agnieszka , Dymecka Kinga , Kot Adam , Ploski Rafal , Jazdzewski Krystian

Background: Risk of developing papillary thyroid carcinoma (PTC), the most frequent thyroid malignancy, is elevated up to 8.6-fold in the first-degree relatives of PTC patients, what could be explained by polygenic action of low-penetrance alleles. Since the DNA-damaging exposure to ionizing radiation is a known risk factor for thyroid cancer, polymorphisms in DNA repair genes are likely to affect this risk. Among the DNA repair proteins, the ATM–CHEK2–BRCA1 axis see...

ea0035p1139 | Thyroid Cancer | ECE2014

The effect of allelic variants of the thyroid hormone receptor β (THRB) gene on the incidence of papillary thyroid carcinoma

Wojcicka Anna , Roslon Marek , Czetwertynska Malgorzata , Swierniak Michal , Dlugosinska Joanna , Kot Adam , Ploski Rafal , Hromada-Judycka Aneta , Swiech Marta , Jazdzewski Krystian

Objectives: Papillary thyroid carcinoma (PTC) is the most common malignancy of the endocrine system. Its heritability is the highest among common cancers, as evidenced by family-based studies. Thyroid hormone receptor β gene (THRB), a known tumor suppressor, is crucial for the proper thyroid function, therefore its polymorphisms are likely to affect the risk for thyroid cancer.Aim of the study: In order to identify alleles that might modify...