Endocrine Abstracts

Intratumoural hypoxia is associated with aggressive and metastatic phenotypes with poor prognosis. The transcription factor HIF-1α is a key regulator of hypoxia-mediated gene expression that is documented to promote tumour growth and metastasis in a wide range of cancers. However its role in the development of thyroid carcinomas is relatively unknown. We have previously shown that HIF-1α is highly active in a range of thyroid cancer cell lines with highest activity o...

Background: Intratumoural hypoxia is associated with an aggressive and metastatic phenotype and poor prognosis. The transcription factor Hypoxia-inducible Factor-1α (HIF-1α) is a key regulator of hypoxia, inducing the expression of genes which promote tumour cell survival, such as carbonic-anhydrase IX (CA-IX) playing a role in cell adhesion, pH regulation and dedifferentiation of the tumours. Here we investigated whether there is cross talk between the HIF-1 and Wnt...

Background: Tissue hypoxia is a hallmark of rapidly proliferating tumours which most frequently adapt and prosper under low oxygen tension. The transcription factor, HIF-1α, is mediating these effects and induces target genes involved in survival, invasion and resistance to drugs and radiation. No data are available on the functional regulation of HIF-1α in thyroid carcinoma cells.Methods: Using thyroid carcinoma cells derived from papillary (N...

The transcription factor HIF-1α regulates hypoxia-mediated gene expression which promotes tumour growth, metastasis and desensitisation to chemo-and radiotherapy. HIF-1 is functional in a range of thyroid-carcinoma cells and is regulated by hypoxia and the PI3K and MAPK-signalling pathways.We aimed to determine if HIF-1 and PI3K were important in the development of a metastatic phenotype and play a role in desensitisation to radiotherapy in thyroid ...

Context: HIF-1α is frequently upregulated in many tumour types and has been shown to be critical for radio- and chemosensitivity in pre-clinical studies. However the regulation and function of HIF-1α is unknown in thyroid carcinomas.Objectives: Here, we evaluated basal expression and regulation of HIF-1α and target genes in primary thyroid carcinomas and in thyroid cancer cell lines (NPA, FTC-133, ARO).Design and out...

Introduction: Thyroid hormones (TH) are essential regulators of metabolism and increase energy expenditure (EE). Mitochondria-rich brown adipose tissue (BAT) is specialised in thermogenesis and significantly contributes to EE. BAT contains essential components of TH action but TH transporters like MCT8 have not been characterised so far. As direct effects on O2 consumption and mitochondrial action have not been investigated before we tested MCT8 expression and direct effects o...

Objective: Abnormal mitochondria are well known in oxyphilic thyroid tumors but recent data also confirm profound mitochondrial alterations in other thyroid carcinomas. These changes are linked to the aggressiveness of the tumors. Our group recently demonstrated in an in vivo model, that inhibition of phosphoinositide 3-kinase (PI3K) signalling suppressed the invasive and metastatic behaviour of thyroid cancer cells. Here, we evaluated whether a modulation of PI3K sig...