Subset of esophageal adenocarcinoma expresses adhesion molecule LI in contrast to squamous cell carcinoma

Background: Esophageal adenocarcinoma is currently the most rapidly increasing cancer in Western populations. LI (CD171), a neural cell adhesion molecule, has an essential function in tumor progression and has been shown to be expressed in the proliferating cells of the intestinal crypts in mice. The aim of the current study was to determine LI expression in esophageal cancer and to evaluate whether LI could serve as a potential marker and therapeutic target for this tumor type. Materials and Methods: LI expression was assessed on a tissue microarray with 257 surgically resected esophageal cancer samples by immunohistochemistry with a monoclonal antibody (Clone UJ127). LI expression was correlated with clinicopathological data. Results: LI was detected in 22 (9%) of 257 esophageal cases, whereas 235 (91%) were LI negative. Nineteen (86% ) of the 22 LI-positive cases were adenocarcinoma. Cross table analysis showed a significant association between LI expression and adenocarcinoma subtype (p<0.001), but not squamous cell carcinoma. Conclusion: LI expression in a subgroup of esophageal cancer is specifically prevalent in adenocarcinoma. Data suggest LI as a potential target for biological therapy in Ll-positive esophageal adenocarcinoma patients.