Glycomic expression in esophageal disease

Glycosylation is among the most common post translation modifications of proteins in humans. Decades of research have demonstrated that aberrant glycosylation can lead to malignant degeneration. Glycoproteomic studies in the past several years have identified techniques that can successfully characterize a glycan or glycan profile associated with a high-grade dysplastic or malignant state. This review summarizes the current glycomic and glycoproteomic literature with specific reference to esophageal cancer. Esophageal adenocarcinoma represents a highly morbid and mortal cancer with a defined progression from metaplasia (Barrett's esophagus) to dysplasia to neoplasia. This disease is highlighted because (1) differences in glycan profiles between the stages of disease progression have been described in the glycoproteomic literature; (2) a glycan biomarker that identifies a given stage may be used as a predictor of disease progression and thus may have significant influence over clinical management; and (3) the differences in glycan profiles between disease and disease-free states in esophageal cancer are more dramatic than in other cancers.