Antitumoral and Antiangiogenic Efficacy of Bisphosphonates In Vitro and in a Murine RENCA Model
Background: Bisphosphonates have shown direct antitumoral activity in vitro, in vivo and even in clinical studies, but the exact mechanism for this has not yet been elucidated. In this study the antiangiogenic potency of zoledronic acid and clodronate were evaluated. Materials and Methods: The effec...
Saved in:
Published in | Anticancer research Vol. 28; no. 2A; pp. 933 - 941 |
---|---|
Main Authors | , , , , , , , |
Format | Journal Article |
Language | English |
Published |
Attiki
International Institute of Anticancer Research
01.03.2008
|
Subjects | |
Online Access | Get full text |
Cover
Loading…
Summary: | Background: Bisphosphonates have shown direct antitumoral activity in vitro, in vivo and even in clinical studies, but the
exact mechanism for this has not yet been elucidated. In this study the antiangiogenic potency of zoledronic acid and clodronate
were evaluated. Materials and Methods: The effects of zoledronic acid and clodronate on the proliferation of endothelial cells
and different tumor cells, and on the activity of protein kinases were investigated. Furthermore in vitro experiments were
performed to evaluate the underlying antiangiogenic mechanism of action. Both bisphosphonates were examined in vivo at different
doses and in daily subcutaneous application in a murine renal cell carcinoma model (RENCA). The antiangiogenic activity was
evaluated by immunohistochemical staining (CD31) and by determination of mouse vascular endothelial growth factor (VEGF) serum
concentration. Results: Zoledronic acid and clodronate inhibited proliferation of endothelial cells at lower concentrations
than the different tumor cell lines did. This effect was more pronounced for zoledronic acid. The activity of almost all tested
kinases was inhibited by zoledronic acid, whereas clodronate showed no effect. In the RENCA model, a significant effect of
zoledronic acid on the primary tumor in a bell-shaped dose response curve with the highest efficacy between 100 Bg/kg 2Ãd
and 200 Bg/kg 1Ãd, was observed. The mean vessel density (MVD) was significantly reduced by both bisphosphonates at different
concentrations. This is the first report on increased mouse VEGF serum concentrations in the RENCA model. Conclusion: The
results indicate that these bisphosphonates, particularly zoledronic acid, possess antitumoral and antiangiogenic activity. |
---|---|
Bibliography: | ObjectType-Article-1 SourceType-Scholarly Journals-1 ObjectType-Feature-2 content type line 23 |
ISSN: | 0250-7005 1791-7530 |