Endocrine Abstracts

The clinical effectiveness of ablative radioiodine treatment is limited by the ability of the sodium iodide symporter (NIS) to uptake 131I. A significant proportion of well-differentiated thyroid tumours are unable to concentrate sufficient radioiodine for effective therapy, and in other tumour models such as breast, where radioiodine uptake would be an attractive therapeutic option, uptake is insufficient. Pituitary tumor-transforming gene-binding factor (PBF/ PTTG...

The pituitary tumor-transforming gene-binding factor (PBF) is a relatively uncharacterised proto-oncogene, which is overexpressed in thyroid tumours. PBF elicits tumor growth in nude mice, whilst thyroid targeted transgenic overexpression in the PBF-Tg mouse induces hyperplasia and macrofollicular lesions, accompanied by induction of the E2 ubiquitin ligase Rad6. Our previous unpublished data showed that PBF binds to p53, and reduces stimulation of downstream target genes by c...

Pituitary tumor transforming gene (PTTG) binding factor (PBF) is a proto-oncogene which is frequently upregulated in endocrine cancers. PBF has previously been determined to contain several putative signal sequences within its 180 amino acids. Previous studies have shown the nuclear localisation signal (NLS) to be functional and prediction software now suggests the presence of a putative leucine-rich nuclear export signal (NES) between residues 17 and 27. PBF is known to shutt...

p53 is rarely mutated in thyroid papillary carcinomas, despite the thyroid being highly sensitive to ionising radiation. The pituitary tumor transforming gene binding factor (PBF) is a proto-oncogene overexpressed in thyroid cancer. Oncogenic levels of PBF result in cell transformation in vitro and tumourigenesis in vivo. By serendipity we have found that PBF interacts directly with the tumour suppressor protein p53. In light of these data we have investigated th...

The human pituitary tumor transforming gene is overexpressed in thyroid cancers; inducing genetic instability through its role as a securin and propagating growth through induction of growth factors. We have demonstrated reduced cellular proliferation following hPTTG overexpression in neuronal cells. We hypothesised targeted hPTTG overexpression in mouse thyroids will result in hyperplastic/neoplastic growth and that stimulation of thyroid cell growth through standard methods ...

PTTG is a multifunctional proto-oncogene overexpressed in thyroid cancers, which binds to p53 and modulates its function. PBF, a binding partner of PTTG, is also overexpressed in thyroid cancer and can transform cells independently of PTTG. Moreover, subcutaneous expression of PBF elicits large tumours in nude mice. Given the established role of ionising radiation in thyroid tumourigenesis, we investigated the relationship between PBF and the tumour suppressor protein p53. PBF...

The pituitary tumor transforming gene binding factor (PBF) is a poorly characterised gene that is over-expressed in pituitary and thyroid tumours. Recently, we showed that subcutaneous expression of PBF elicits tumours in nude mice, and expression correlates with thyroid tumour recurrence in man. Given the established role of ionising radiation in thyroid tumourigenesis, we have now investigated the relationship between PBF and the tumour suppressor gene p53, a central compone...

The progression of thyroid cancer is dependent on cell motility, a highly complex process that involves the co-ordination of multiple signalling pathways, cell adhesion, and actin dynamics. The proto-oncogene pituitary tumor-transforming gene (PTTG)-binding factor (PBF/PTTG1IP) potently stimulates thyroid cancer cell migration and invasion via PBF phosphorylation by Src kinase at residue Y174. Recent phosphoproteomic and RNA-Seq analyses revealed that upregulation of PBF in Nt...

The proto-oncogene pituitary tumor transforming gene binding factor (PTTG1IP/PBF) is overexpressed in multiple tumours and associated with tumour progression. One of the tumourigenic processes that PBF can mediate is cell motility. PBF can induce cell invasion in both thyroid and breast cancer cell lines. However, in contrast to wild-type (WT) PBF, the Y174A PBF mutant was not able to induce the invasiveness of thyroid or breast cancer cells. The Y174 residue is highly phospho...

By exploiting the canonical function of the sodium iodide symporter (NIS), ablative radioiodide therapy is an effective treatment for thyroid cancer. However, a subset of patients are unable to accumulate sufficient radioiodide due to decreased expression and/or plasma membrane localisation of NIS. Radioiodide therapy has been proposed as a viable treatment for breast cancer, but is hampered by low levels of NIS membrane localisation. Currently, the regulation of NIS trafficki...