title: MicroRNAs miR-146-5p and let-7f as prognostic tools for aggressive papillary thyroid carcinoma: a case report.
abstract: Papillary thyroid cancer (PTC) is the most incident histotype of thyroid cancer. A certain fraction of PTC cases (5%) are irresponsive to conventional treatment, and refractory to radioiodine therapy. The current prognostic factors for aggressiveness are mainly based on tumor size, the presence of lymph node metastasis, extrathyroidal invasion and, more recently, the presence of the BRAFT1799A mutation. MicroRNAs (miRNAs) have been described as promising molecular markers for cancer as their deregulation is observed in a wide range of tumors. Recent studies indicate that the over-expression of miR-146b-5p is associated with aggressiveness and BRAFT1799A mutation. Furthermore, down-regulation of let-7f is observed in several types of tumors, including PTC. In this study, we evaluated the miR146b-5p and let-7f status in a young male patient with aggressive, BRAFT1799A-positive papillary thyroid carcinoma, with extensive lymph node metastases and short-time recurrence. The analysis of miR-146b-5p and let-7f expression revealed a distinct pattern from a cohort of PTC patients, suggesting caution in evaluating miRNA expression data as molecular markers of PTC diagnosis and prognosis.
authors.affiliation: Department of Cell and Developmental Biology, Institute of Biomedical Sciences, University of Sao Paulo, Sao Paulo, SP, Brazil.
authors.forename: Murilo Vieira
authors.initials: MV
authors.lastname: Geraldo
authors.forename: Cesar Seigi
authors.initials: CS
authors.lastname: Fuziwara
authors.forename: Celso Ubirajara Moretto
authors.initials: CU
authors.lastname: Friguglieti
authors.forename: Ricardo Borges
authors.initials: RB
authors.lastname: Costa
authors.forename: Marco Aurélio Vamondes
authors.initials: MA
authors.lastname: Kulcsar
authors.forename: Alex Shimura
authors.initials: AS
authors.lastname: Yamashita
authors.forename: Edna Teruko
authors.initials: ET
authors.lastname: Kimura
mesh_terms: D014408:Biomarkers, Tumor / Q000378:metabolism*; D002277:Carcinoma / Q000235:genetics*; D002291:Carcinoma, Papillary; D015536:Down-Regulation; D015972:Gene Expression Regulation, Neoplastic; D006801:Humans; D008207:Lymphatic Metastasis; D008297:Male; D035683:MicroRNAs / Q000378:metabolism*; D009154:Mutation / Q000235:genetics*; D011379:Prognosis; D048493:Proto-Oncogene Proteins B-raf / Q000235:genetics*; D012008:Recurrence; D000077273:Thyroid Cancer, Papillary; D013964:Thyroid Neoplasms / Q000235:genetics*; D055815:Young Adult
chemical_list: D014408:Biomarkers, Tumor; C542542:MIRN146 microRNA, human; D035683:MicroRNAs; C487931:mirnlet7 microRNA, human; C482119:BRAF protein, human; D048493:Proto-Oncogene Proteins B-raf