The metabolite 3-hydroxiglutaric acid effectively reduces glioblastoma growth in vivo by affecting the structural integrity of tumor vasculature.

3-Hydroxiglutaric acid (3-OH-GA) is a disease-specific metabolite that accumulates in tissues and body fluids of patients with Glutaric aciduria type I (GAI) and has been associated with vascular abnormalities in these kindreds. Here, we demonstrate that 3-OH-GA also affects the integrity of tumor vessels leading to tumor growth inhibition in a subcutaneous model of human glioblastoma multiforme (GBM). This effect correlated with a marked decrease of VE-Cadherin expression in endothelium of 3-OH-GA-treated tumors. Furthermore, in vitro observations indicated also a direct effect of 3-OH-GA in glioma cells that showed defective mitosis and significant proliferation inhibition. In summary, the GAI-specific metabolite 3-OH-GA significantly inhibited growth of GBM xenografts by affecting the structural integrity of tumor blood vessels and in addition by causing defective mitosis and proliferation inhibition of tumor cells.