Endocrine Abstracts

Introduction: Cells with stem-like properties have been reported in benign and malignant thyroid diseases, and can be propagated by culturing them as non-adherent spheres.Design: Aim of the present study was to widely characterize the stem-like cells in tumor and normal thyroid tissues and in the corresponding in vitro-cultured thyrospheres, and to investigate in vivo the proangiogenic potential of thyrospheres in a zebrafish model....

Non-functioning pituitary tumors (NFPTs), although benign in nature, frequently present local invasiveness that strongly reduces neurosurgery success. Medical therapy is still under debate, although dopamine (DA) receptor 2 (DRD2) agonists may induce tumor shrinkage in some patients. Aims of this study were: 1) to evaluate the effect of DR2D agonist BIM53097 on migration and invasion of NFPT cells, 2) to investigate the molecular mechanisms regulating the motility of these cel...

Epigenetic deregulation is emerging as a component of the parathyroid tumorigenesis. We identified a long non-coding RNA (LNCRNA) signature clearly distinguishing parathyroid adenomas (PAds) and carcinomas from normal glands. Among the deregulated LncRNAS, HAR1B was upregulated in PAds harboring the common chromosome 11q loss of heterozygosity (Chr11q-LOH; n=10) compared with PAds harboring normal chromosome 11 haplotype (Chr11q-WT; n=12; P&...

We previously described aberrant expression of microRNAs belonging to the chromosome 19 cluster (C19MC) and the close miR-371-373 cluster in two-thirds of parathyroid carcinomas (PCas). Therefore, we investigated the involvement of the miR-371-373 cluster in parathyroid tumours, where miR-372 was the most consistently upregulated. miR-372 is known to be highly expressed in human embryonic stem cells and definitely downregulated upon differentiation. Moreover, miR-372 promotes ...

Though there is no evidence of a constitutive nuclear accumulation of β-catenin, the Wnt/β-catenin pathway might be deregulated in parathyroid tumours. We investigated unphosphorylated active β-catenin distribution by western blot in 16 typical parathyroid adenomas (PAds): β-catenin accumulation in the nuclear protein fractions varied from the levels detected in Caco-2 cells with constitutively active Wnt signalling (three PAds) to the levels measured in HE...

Parathyroid carcinomas (PCas) are rare endocrine malignant neoplasia characterized by an abnormal PTH secretion and, consequently, severe and uncontrolled hypercalcemia. Clinically, the preoperative diagnosis can be misleading, because PCas share some molecular and clinical similarities with benign lesions and are often indolent. The histological diagnosis of carcinoma is achieved based on the presence of mitotic nuclear figures, capsular invasion, parenchyma infiltration, vas...

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Embryonic transcription factors have been involved in tumourigenesis. The transcription factor TBX1 regulates the embryonic parathyroid cells fate. Indeed, it has never been investigated in human adult parathyroids. Here, expression, function and regulation of the TBX1 gene were analyzed in adult normal and tumour parathyroid tissues. Immunohistochemistry identified 30–70% (mean±S.E.M, 52.0±7.3%) of cells expressing TBX1 at nuclear levels...

An embryonic gene signature has been suggested in parathyroid tumours. We investigated the expression of early embryonic stem cell (ESC) genes in parathyroid tumours. POU5F1/OCT4, SOX2 and NANOG transcripts were detected in almost all parathyroid adenomas (PAds; n=22) and atypical PAds (n=3), besides the variable expression of ESC genes KLF4, EGR1, and REX1/ZFP42. OCT4, SOX2 and NANOG proteins expression w...

Parathyroid carcinoma is a rare cause of primary hyperparathyroidism. Though the loss of the oncosuppressor HRPT2 gene product, parafibromin, has been involved in the hyperparathyroidism-jaw tumor syndrome and in a consistent set of sporadic parathyroid carcinomas, parathyroid carcinogenesis remains obscure. MicroRNAs (miRNAs) are a new class of small, non-coding RNAs implicated in embryonic development and cancer. A deregulated miRNA can induce the aberrant expression ...