title: MicroRNAs in thyroid development, function and tumorigenesis.
abstract: MicroRNAs (miRNAs) are important post-transcriptional regulators of gene expression that modulate the vast majority of cellular processes. During development, the correct timing and expression of miRNAs in the tissue differentiation is essential for organogenesis and functionality. In thyroid gland, DICER and miRNAs are necessary for accurately establishing thyroid follicles and hormone synthesis. Moreover, DICER1 mutations and miRNA deregulation observed in human goiter influence thyroid tumorigenesis. The thyroid malignant transformation by MAPK oncogenes is accompanied by global miRNA changes, with a marked reduction of "tumor-suppressor" miRNAs and activation of oncogenic miRNAs. Loss of thyroid cell differentiation/function, and consequently iodine trapping impairment, is an important clinical characteristic of radioiodine-refractory thyroid cancer. However, few studies have addressed the direct role of miRNAs in thyroid gland physiology. Here, we focus on what we have learned in the thyroid follicular cell differentiation and function as revealed by cell and animal models and miRNA modulation in thyroid tumorigenesis.
authors.affiliation: Department of Cell and Developmental Biology, Institute of Biomedical Sciences, University of São Paulo, São Paulo, SP, Brazil. Electronic address: cesar.fuziwara@usp.br.
authors.forename: Cesar Seigi
authors.initials: CS
authors.lastname: Fuziwara
authors.affiliation: Department of Cell and Developmental Biology, Institute of Biomedical Sciences, University of São Paulo, São Paulo, SP, Brazil. Electronic address: etkimura@usp.br.
authors.forename: Edna Teruko
authors.initials: ET
authors.lastname: Kimura
mesh_terms: D000818:Animals; D002454:Cell Differentiation; D002471:Cell Transformation, Neoplastic / Q000235:genetics / Q000378:metabolism / Q000473:pathology; D053487:DEAD-box RNA Helicases / Q000235:genetics* / Q000378:metabolism; D015972:Gene Expression Regulation, Neoplastic; D006042:Goiter / Q000235:genetics* / Q000378:metabolism / Q000503:physiopathology; D006801:Humans; D007455:Iodine / Q000378:metabolism; D035683:MicroRNAs / Q000235:genetics* / Q000378:metabolism; D043244:Ribonuclease III / Q000235:genetics* / Q000378:metabolism; D015398:Signal Transduction; D000072637:Thyroid Epithelial Cells / Q000378:metabolism / Q000473:pathology; D013961:Thyroid Gland / Q000378:metabolism* / Q000503:physiopathology; D013963:Thyroid Hormones / Q000235:genetics / Q000378:metabolism; D013964:Thyroid Neoplasms / Q000235:genetics* / Q000378:metabolism / Q000503:physiopathology
chemical_list: D035683:MicroRNAs; D013963:Thyroid Hormones; D007455:Iodine; C408087:DICER1 protein, human; D043244:Ribonuclease III; D053487:DEAD-box RNA Helicases
keywords: DICER; Iodine metabolism-related genes; MicroRNA; Thyroid; Thyroid cell differentiation; Thyroid tumor