EGFRvIII induces the expression of angiopoietin-like 4 both in vitro and in vivo. Real-time PCR assay of samples obtained from mock, wtEGFR, and EGFRvIII-transfected LN229 cells (A) and tumors (C) was performed. Total RNA was extracted from the cells or excised tumors and reverse-transcribed. Real-time PCR was performed based on TaqMan Gene Expression Assays. Beta-actin was used as the endogenous control. ELISA was performed with cell-conditioned medium (B) and the supernatants of the homogenized tumors (D). Data shown are the means ± SEM (n=4-6). Significant differences are shown: *** p<0.001. N.D. denotes not detected.