Pituitary Tumour Transforming Gene (PTTG), PTTG Binding Factor (PBF) and Related Growth Factor Expression in Thyroid Cancer

Dr Chris McCabe, Queen Elizabeth Hospital, Birmingham

Final report

Thyroid cancer is relatively common, and in most patients can be treated effectively. A number of patients, however, have recurrent tumours, and there is a current lack of genetic clues as to the likelihood of this happening. Recently, a new gene has been discovered to be important in pituitary, colon and other tumours. Pituitary tumor transforming gene (PTTG) works by attaching itself to a binding protein called PBF, and then stimulating the expression of another gene called fibroblast growth factor 2 (FGF-2). FGF-2 has previously been linked with the growth of thyroid tumours.

We have now shown that PTTG and FGF-2 are unusually high in thyroid cancer, but less so in multinodular goitres or Graves' disease. In addition, increased FGF-2 levels were associated with lymph node invasion and metastasis - two indicators of tumour severity. High PTTG expression was also associated with the likelihood of tumours recurring. Overall, therefore, our findings suggest that PTTG and FGF-2 expression are good potential prognostic factors which may predict the progression of thyroid cancers, but play less important roles in Graves' disease and multinodular goitres.