We previously showed that the expression levels of glucose transporter 2 (GLUT2) and glucagon-like peptide 1 (GLP-1) receptor in beta cells in nontumor areas were downregulated by hyperinsulinemia.21 Similarly, we hypothesized that there might be a mechanism regulating IAPP expression in insulinoma patients. The gene discussed is IAPP; the disease is Hyperinsulinemia.