Trophic and neurotrophic factors in human pituitary adenomas (Review).

The pituitary gland is an organ that functionally connects the hypothalamus with the peripheral organs. The pituitary gland is an important regulator of body homeostasis during development, stress, and other processes. Pituitary adenomas are a group of tumors arising from the pituitary gland: they may be subdivided in functional or non-functional, depending on their hormonal activity. Some trophic and neurotrophic factors seem to play a key role in the development and maintenance of the pituitary function and in the regulation of hypothalamo-pituitary-adrenocortical axis activity. Several lines of evidence suggest that trophic and neurotrophic factors may be involved in pituitary function, thus suggesting a possible role of the trophic and neurotrophic factors in the normal development of pituitary gland and in the progression of pituitary adenomas. Additional studies might be necessary to better explain the biological role of these molecules in the development and progression of this type of tumor. In this review, in light of the available literature, data on the following neurotrophic factors are discussed: ciliary neurotrophic factor (CNTF), transforming growth factors ß (TGF­ß), glial cell line-derived neurotrophic factor (GDNF), nerve growth factor (NGF), vascular endothelial growth factor (VEGF), vascular endothelial growth inhibitor (VEGI), fibroblast growth factors (FGFs) and epidermal growth factor (EGF) which influence the proliferation and growth of pituitary adenomas.

Involvement of pro-inflammatory cytokines and growth factors in the pathogenesis of Dupuytren's contracture: a novel target for a possible future therapeutic strategy?

Dupuytren's contracture (DC) is a benign fibro-proliferative disease of the hand causing fibrotic nodules and fascial cords which determine debilitating contracture and deformities of fingers and hands. The present study was designed to characterize pro-inflammatory cytokines and growth factors involved in the pathogenesis, progression and recurrence of this disease, in order to find novel targets for alternative therapies and strategies in controlling DC. The expression of pro-inflammatory cytokines and of growth factors was detected by immunohistochemistry in fibrotic nodules and normal palmar fascia resected respectively from patients affected by DC and carpal tunnel syndrome (CTS; as negative controls). Reverse transcription (RT)-PCR analysis and immunofluorescence were performed to quantify the expression of transforming growth factor (TGF)-ß1, interleukin (IL)-1ß and vascular endothelial growth factor (VEGF) by primary cultures of myofibroblasts and fibroblasts isolated from Dupuytren's nodules. Histological analysis showed high cellularity and high proliferation rate in Dupuytren's tissue, together with the presence of myofibroblastic isotypes; immunohistochemical staining for macrophages was completely negative. In addition, a strong expression of TGF-ß1, IL-1ß and VEGF was evident in the extracellular matrix and in the cytoplasm of fibroblasts and myofibroblasts in Dupuytren's nodular tissues, as compared with control tissues. These results were confirmed by RT-PCR and by immunofluorescence in pathological and normal primary cell cultures. These preliminary observations suggest that TGF-ß1, IL-1ß and VEGF may be considered potential therapeutic targets in the treatment of Dupuytren's disease (DD).