Considering that glioma progression from lower-grade tumors to highly malignant GBM is characterized by increasing intratumoral expression of leptin [35] as well as induction of angiogenesis [38,39], we investigated angiogenic properties (induction of tube formation) of GBM-derived leptin using endothelial cell models and specific ObR antagonists. The gene discussed is LEP; the disease is glioblastoma.