Endocrine Abstracts

Reduced expression or activity of the thyroid hormone receptors (TRs) are common events in cancer, suggesting that these receptors could act as tumor suppressors. We have previously shown that TRβ expression in SK-hep1 hepatocarcinoma cells (SK-TRβ cells), reduces tumor growth and strikingly inhibits invasion, extravasation, and metastasis formation in nude mice. These effects could be related to a decreased expression in these cells of prometastatic genes, such as C...

Transforming growth factor beta (TGFβ), which plays a key role in cancer and fibrotic disorders, mediates its actions mainly through activation of Smad transcription factors, which bind to Smad Binding Elements (SBEs) in target genes. We have previously observed that the thyroid hormone T3 blocks transactivation of SBE-containing reporter plasmids by TGFβ, and represses transcription of endogenous TGFβ target genes. We have now analysed the thyroid ho...

Transforming growth factor β (TGFβ) signals through activation of Smad transcription factors, which bind to Smad binding elements (SBEs) in target genes. TGFβ can promote cancer cell proliferation and invasion, and plays a key role in the pathogenesis of scleroderma and other fibrotic disorders. We have previously shown that the thyroid hormone receptors (TRs) can block tumor growth and invasion. We now have analyzed the possibility that TRs could antagonize TGF...

Nuclear corepressor 1 (NCoR) associates with nuclear receptors and other transcription factors leading to transcriptional repression. Genomic studies have shown the presence of inactivating mutations of the NCoR gene in human tumours and we have found that NCoR depletion with siRNA in hepatocarcinoma SK-hep1 cells enhances invasion, tumour growth and metastasis in nude mice, while expression of the thyroid hormone receptor β (TRβ) increases NCoR levels, repr...