title: Molecular Analysis of TTF-1 and TTF-2 Genes in Patients with Early Onset Papillary Thyroid Carcinoma.
abstract: Two common variants, close from TTF-1 and TTF-2, were shown to predispose to thyroid cancer (TC) in European populations. We aimed to investigate whether TTF-1 and TTF-2 variants might contribute to TC early onset (EO). Tumor samples from eighteen patients with papillary TC (PTC), who underwent total thyroidectomy at an age of ≤21, were screened for TTF-1 and TTF-2 variants. No TTF-1 variants were documented; two novel germinal TTF-2 variants, c.200C>G (p.A67G) and c.510C>A (p.A170A), were identified in two patients. Two already described TTF-2 variants were also documented; the allelic frequency among patients was not different from that observed among controls. Moreover, RET/PTC rearrangements and the BRAFV600E mutation were identified in 5/18 and 2/18 PTCs, respectively. Thyroglobulin (TG) and thyroid peroxidase (TPO) expression was found to be significantly decreased in tumors, and the lowest level of TPO expression occurred in a tumor harboring both the p.A67GTTF-2 variant and a RET/PTC3 rearrangement.
authors.affiliation: Centro de Investigação de Patobiologia Molecular, Instituto Português de Oncologia de Lisboa Francisco Gentil E.P.E., 1099-023 Lisboa, Portugal.
authors.forename: Carla
authors.initials: C
authors.lastname: Espadinha
authors.forename: Ana Luísa
authors.initials: AL
authors.lastname: Silva
authors.forename: Rafael
authors.initials: R
authors.lastname: Cabrera
authors.forename: Maria João
authors.initials: MJ
authors.lastname: Bugalho