Differential expression of Hedgehog/Notch and transforming growth factor-β in human abdominal aortic aneurysms.

Objective: The molecular mechanisms leading to the development of abdominal aortic aneurysms (AAAs) remain poorly understood. The aim of this study was to determine the expression of Sonic Hedgehog (SHh), transforming growth factor β (TGF-β), and Notch signaling components in human aneurysmal and nonaneurysmal aorta in vivo.

Methods: Paired tissue samples were obtained from aneurysmal and nonaneurysmal (control) segments of the aortic wall of eight patients with suitable anatomy undergoing open repair of infrarenal AAAs.

Pathogenesis of Barrett's esophagus: bile acids inhibit the Notch signaling pathway with induction of CDX2 gene expression in human esophageal cells.

Background: Barrett's esophagus (BE) is the predominant risk factor for the development of esophageal adenocarcinoma. BE is characterized by intestinal metaplasia with goblet cells. Reflux of bile acids is known to induce intestinal metaplasia, but the mechanisms are unclear.