Purpose: Dopamine (DA) therapy of non-functioning pituitary adenomas (NFA) can result in tumor stabilization and shrinkage. However, the mechanism of action is still unknown. Previous evidence showed that DA can inhibit pituitary Vascular Endothelial Growth Factor expression (VEGF), that may be involved in pituitary tumor growth. The aim of our study was to clarify whether VEGF secretion Methods: We assessed DA receptor subtype 2 (DR2) expression in 20 NFA primary cultures, where 20 modulation might mediate the effects of DA agonists on cell proliferation in human NFA. we also investigated the effects of a selective DR2 agonist, cabergoline (Cab), on VEGF secretion and on cell viability. Results: All NFA samples expressed a-subunit and DR2 was expressed in 11 samples. In DR2 expressing tumors, Cab significantly reduced cell viability (-25%; P<0.05) and VEGF secretion (-20%; P<0.05). These effects were counteracted by treatment with the DA antagonist sulpiride. Cab antiproliferative effects were blocked by VEGF. Conclusion:
Cabergoline reduces cell viability in non functioning pituitary adenomas by inhibiting Vascular Endothelial Growth Factor secretion
GAGLIANO, Teresa;FILIERI, Carlo;MINOIA, Mariella;BURATTO, Mattia;TAGLIATI, Federico;AMBROSIO, Maria Rosaria;LAPPARELLI, Marcello;DEGLI UBERTI, Ettore;ZATELLI, Maria Chiara
2012
Abstract
Purpose: Dopamine (DA) therapy of non-functioning pituitary adenomas (NFA) can result in tumor stabilization and shrinkage. However, the mechanism of action is still unknown. Previous evidence showed that DA can inhibit pituitary Vascular Endothelial Growth Factor expression (VEGF), that may be involved in pituitary tumor growth. The aim of our study was to clarify whether VEGF secretion Methods: We assessed DA receptor subtype 2 (DR2) expression in 20 NFA primary cultures, where 20 modulation might mediate the effects of DA agonists on cell proliferation in human NFA. we also investigated the effects of a selective DR2 agonist, cabergoline (Cab), on VEGF secretion and on cell viability. Results: All NFA samples expressed a-subunit and DR2 was expressed in 11 samples. In DR2 expressing tumors, Cab significantly reduced cell viability (-25%; P<0.05) and VEGF secretion (-20%; P<0.05). These effects were counteracted by treatment with the DA antagonist sulpiride. Cab antiproliferative effects were blocked by VEGF. Conclusion:I documenti in SFERA sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
