Differential gene expression in RT2 Dll4
+/+ vs. RT2 Dll4
+/- insulinomas. Total RNA was isolated from harvested insulinomas (2-3 tumors/mouse, n = 5 for each genotype) and gene expression analysis of tumor tissues was performed by quantitative RT-PCR for indicated genes involved in angiogenesis. Gene expression levels were normalized to β-actin levels. Error bars represent SD.