Media type: E-Article Title: Quercetin enhances transforming growth factor β1, secretion by human ovarian cancer cells Contributor: Scambia, Giovanni; Panici, Pierluigi Benedetti; Ranelletti, F. O.; Ferrandina, G.; de Vincenzo, R.; Piantelli, M.; Masciullo, V.; Bonanno, G.; Isola, G.; Mancuso, S. imprint: Wiley, 1994 Published in: International Journal of Cancer Language: English DOI: 10.1002/ijc.2910570214 ISSN: 0020-7136; 1097-0215 Keywords: Cancer Research ; Oncology Origination: Footnote: Description: <jats:title>Abstract</jats:title><jats:p>Our study demonstrates that quercetin (Q)‐induced growth‐inhibitory activity in ovarian cancer cells may be mediated by modulation of transforming growth factor β<jats:sub>1</jats:sub> (TGFβ<jats:sub>1</jats:sub>) production. We used the OVCA 433 cell line which is very sensitive to the anti‐proliferative effect of Q and expresses high‐affinity, low‐capacity TGFβ<jats:sub>1</jats:sub> receptors. Conditioned medium (CM) from Q‐treated cells is able to displace <jats:sup>125I</jats:sup>‐TGFβ<jats:sub>1</jats:sub> from binding to its receptor; moreover Q (10 μM) increases TGFβ<jats:sub>1</jats:sub> activity in CM in a time‐dependent fashion starting after 4 hr and reaching a maximum by 24 hr of Q treatment. Q‐induced growth inhibition is reversed by a neutralizing anti‐TGFβ<jats:sub>1</jats:sub> MAb both in OVCA 433 and in a clonogenic assay of cells from a primary ovarian tumor. Q‐induced increase of TGFβ<jats:sub>1</jats:sub> activity in CM is specific since other anti‐proliferative compounds, such as Dexamethasone, which is as active on the cell cycle as Q, had no effect on TGFβ<jats:sub>1</jats:sub> secretion. Northorn‐blot analysis of TGFβ<jats:sub>1</jats:sub> mRNA levels at various times of Q (10 μM) exposure revealed that there was no increase, suggesting that regulation of TGFβ<jats:sub>1</jats:sub> occurs at post‐transcription at levels. © 1994 Wiley‐Liss, Inc.</jats:p>