News Story: Full Text
Sponsored By
NovoCure Trial
Please Click On The Above Banner For More Details
Braintumor Website

 

MGMT modulates glioblastoma angiogenesis and response to the tyrosine kinase inhibitor sunitinib.


Posted on: 02/25/2010

Neuro Oncol. 2010 Feb 23. [Epub ahead of print]

MGMT modulates glioblastoma angiogenesis and response to the tyrosine kinase inhibitor sunitinib.

Chahal M, Xu Y, Lesniak D, Graham K, Famulski K, Christensen JG, Aghi M, Jacques A, Murray D, Sabri S, Abdulkarim B.

Department of Oncology (M.C., Y.X., D.L., K.G., A.J., D.M., S.S., B.A.) and Alberta Transplant Applied Genomics Centre (K.F.), University of Alberta, Alberta, Canada; Oncology Research Unit, Pfizer Global Research and Development La Jolla Laboratories (J.G.C.) and Department of Neurosurgery, University of California-San Francisco (M.A.), San Francisco, California.

 

Angiogenesis inhibitors, such as sunitinib, represent a promising strategy to improve glioblastoma (GBM) tumor response. In this study, we used the O(6)-methylguanine methyltransferase (MGMT)-negative GBM cell line U87MG stably transfected with MGMT (U87/MGMT) to assess whether MGMT expression affects the response to sunitinib. We showed that the addition of sunitinib to standard therapy (temozolomide [TMZ] and radiation therapy [RT]) significantly improved the response of MGMT-positive but not of MGMT-negative cells. Gene expression profiling revealed alterations in the angiogenic profile, as well as differential expression of several receptor tyrosine kinases targeted by sunitinib. MGMT-positive cells displayed higher levels of vascular endothelial growth factor receptor 1 (VEGFR-1) compared with U87/EV cells, whereas they displayed decreased levels of VEGFR-2. Depleting MGMT using O(6)-benzylguanine suggested that the expression of these receptors was directly related to the MGMT status. Also, we showed that MGMT expression was associated with a dramatic increase in the soluble VEGFR-1/VEGFA ratio, thereby suggesting a decrease in bioactive VEGFA and a shift towards an antiangiogenic profile. The reduced angiogenic potential of MGMT-positive cells is supported by: (i) the decreased ability of their secreted factors to induce endothelial tube formation in vitro and (ii) their low tumorigenicity in vivo compared with the MGMT-negative cells. Our study is the first to show a direct link between MGMT expression and decreased angiogenicity and tumorigenicity of GBM cells and suggests the combination of sunitinib and standard therapy as an alternative strategy for GBM patients with MGMT-positive tumors.

 

 PMID: 20179017 [PubMed - as supplied by publisher] 

 

 


Click HERE to return to brain tumor news headlines


Home | Brain Tumor Guide | FAQs | Find A Treatment
Noteworthy Treatments | News | Virtual Trial | Videos | Novocure Optune® | Newsletter
Donations | Brain Tumor Centers | Survivor Stories | Temodar®
Fundraising For Research | Unsubscribe | Contact Us

Copyright (c) 1993 - 2019 by:
The Musella Foundation For Brain Tumor Research & Information, Inc
1100 Peninsula Blvd
Hewlett, NY 11557
888-295-4740