[Molecular events associated with Barrett's oesophagus].

The development and progression of Barrett's epithelium are accompanied with the acquisition of many molecular changes of the oesophageal mucosa. Gastro-oesophageal reflux and inflammation cause the oxidative stress and free-radical generations, which result in the expression of oxidative-stress-related genes and the induction of DNA damage. The development of Barrett's epithelium follows a metaplasia-dysplasia-adenocarcinoma sequence, characterized by the accumulation of many genetic and epigenetic alterations, which are seen in carcinogenesis. Abnormalities in the expression of tumor suppressor genes, such as p53, p16, APC, and a number of molecules involved in cell proliferation, apoptosis or angiogenesis are observed. These genetic alterations affecting the cancer hallmarks provide a better understanding of the etiology and pathogenesis of the disease.