Notch1 Is a Downstream Effector of Raf-1 Signaling in Gastrointestinal Carcinoid Cells

Abstract

Introduction: The Raf-1 pathway has been shown to be a tumor suppressing pathway in human carcinoid cancer, inhibiting in vitro as well as in vivo growth and the expression of Achaete Scute Complex-Like1 (ASCL1), a transcription factor central in carcinoid oncogenesis. Interestingly, the Notch1 pathway is capable of inducing many of the same anti-carcinoid effects. As the downstream effectors of the Raf-1 pathway have not been well described, we hypothesized that Notch1 is a downstream effector of the Raf-1 pathway.