Send to

Choose Destination
Proc Natl Acad Sci U S A. 2006 Dec 19;103(51):19478-83. Epub 2006 Dec 12.

The small-molecule VEGF receptor inhibitor pazopanib (GW786034B) targets both tumor and endothelial cells in multiple myeloma.

Author information

Department of Medical Oncology, Dana-Farber Cancer Institute, Harvard Medical School, Boston, MA 02115, USA.


A critical role for vascular endothelial factor (VEGF) has been demonstrated in multiple myeloma (MM) pathogenesis. Here, we characterized the effect of the small-molecule VEGF receptor inhibitor pazopanib on MM cells in the bone marrow milieu. Pazopanib inhibits VEGF-triggered signaling pathways in both tumor and endothelial cells, thereby blocking in vitro MM cell growth, survival, and migration, and inhibits VEGF-induced up-regulation of adhesion molecules on both endothelial and tumor cells, thereby abrogating endothelial cell-MM cell binding and associated cell proliferation. We show that pazopanib is the first-in-class VEGF receptor inhibitor to inhibit in vivo tumor cell growth associated with increased MM cell apoptosis, decreased angiogenesis, and prolonged survival in a mouse xenograft model of human MM. Low-dose pazopanib demonstrates synergistic cytotoxicity with conventional (melphalan) and novel (bortezomib and immunomodulatory drugs) therapies. Finally, gene expression and signaling network analysis show transcriptional changes of several cancer-related genes, in particular c-Myc. Using siRNA, we confirm the role of c-Myc in VEGF production and secretion, as well as angiogenesis. These preclinical studies provide the rationale for clinical evaluation of pazopanib, alone and in combination with conventional and novel therapies, to increase efficacy, overcome drug resistance, reduce toxicity, and improve patient outcome in MM.

[Indexed for MEDLINE]
Free PMC Article

Supplemental Content

Full text links

Icon for HighWire Icon for PubMed Central
Loading ...
Support Center