Overexpression of Brachyury and IGF1R in Thyroid Papillary Carcinoma cells: different phenotypes and asocciation with pediatric Thyroid Nodular Pathology

MARTIN AYELEN; MARÍA CELIA FERNANDEZ; SOFÍA MIRAGLIA; MARTÍN MEDÍN; PATRICIA PAPENDIECK; FLORENCIA CLEMENT; ELENA DE MATTEO; ANA CHIESA; PATRICIA PENNISI

Buenos Aires

Congreso; 11th International Meeting of Paediatric Endocrinology (IMPE); 2023

In pediatrics, thyroid tumor stratification is difficult to assess.Epithelial-mesenchymal transition (EMT), plays a role in tumordevelopment. In human carcinomas Brachyury (Brachy) has beenidentified as a regulator of EMT associated to malignancy. TheInsulin Like Growth Factors (IGFs) are mitogens that play importantroles in both normal and neoplastic growth. To date, no informationabout Brachy and IGF1R expression in pediatric thyroidnodular disease is available.Aim: To evaluate Brachy and IGF1R expression in thyroid nodularsamples from pediatric patients and to study the effect ofBrachy and IGF1R overexpression in a thyroid papillary carcinomacell line (TPC) in vitro. Methods: Paraffin-embedded samples from pediatric patientswith Thyroid Papillary Carcinomas (TPCa), Follicular Adenomas(FA) or Benign Thyroid Nodular disease (BTN) were processed forBrachy and IGF1R immunostaining. TPC cells were used to obtainclones overexpressing Brachy (TPC.BR4 and TPC.BR6) andIGF1R (TPC.IGF1R5 and TPC.IGF1R7). Gene expression wasquantified by rqPCR. Phaloidin IF staining, Viability and apoptosisassays (3 days) and wounding assays (24h) were carried out.Protein extracts were obtained from whole lysates and processedby western blotting (WB).Results: 50 samples were analysed, 17 from BTN. Only TPCaand FA showed positive staining for Brachy (15/24TPCa;5/9FA)and IGF1R (11/24TPCa;4/9FA). In carcinomas, positivity forIGF1R was only detected when Brachy was present. In vitro,Brachy overexpression in TPC cells increased proliferation(**p