Endocrine Abstracts

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...

Primary hyperparathyroidism (PHPT) is associated with increased risk of kidney stones. Hypercalciuria and urine oxalate excretion are considered risk factors for urolithiasis in PHPT stone-formers. Recently, the anion-exchanger SLC26A6 has been involved in the oxalate metabolism. Slc26a6-null mice showed hyperoxalemia, hyperoxaluria resulting in dramatic calcium oxalate urolithiasis. We tested the hypothesis that urine oxalate excretion in PHPT patients might be modulat...

A peculiar characteristic of parathyroid tissue is the ability to spontaneously induce angiogenesis, to proliferate and to secrete PTH when autotransplanted in patients undergoing total parathyroidectomy. Since stem/progenitor cells have been involved in the process of tissue regeneration, we searched for putative parathyroid progenitors from human normal and tumoral parathyroids. By immunohistochemistry, FACS analysis and cell culture we identified parathyroid cells positive ...

The cut-off values able to differentiate between reactive or neoplastic C cell hyperplasia (CCH) or to predict sporadic medullary thyroid cancer (MTC) are still debated both for basal and stimulated calcitonin (bCT and sCT). Aim of the present study was to define the prevalence and the histological patterns of CCH in 15 patients with multinodular goiter (MNG), bCT>10 pg/ml and sCT levels >50 pg/ml. These data were compared with those from 16 patients with MNG and bCT l...

The two regulatory subunits (R1 and R2) of PKA are differentially expressed in several cancer cell lines and studies indicate distinct roles for these subunits in growth control. Recently, mutations of the regulatory subunit 1A of PKA gene have been identified in patients with Carney complex (CNC). The aim of this study was to evaluate the expression of the different PKA regulatory subunits (R1A, R2A, R2B) in adrenocortical tumors not associated with CNC, as well as the effect...

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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....

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...