Carbonic anhydrases II, IX, and XII in Barrett's esophagus and adenocarcinoma.

The aim of our retrospective study was to investigate the expression and clinical significance of the cancer-associated carbonic anhydrases (CAs) II, IX, and XII in Barrett's esophagus and esophageal adenocarcinoma (EAC). We evaluated 101 archival specimens from patients with EAC as well as seven and 26 samples from patients with high-and low-grade dysplasia, respectively. In addition, normal esophageal squamous epithelium, gastric, and intestinal metaplasia were analyzed when present. The expression patterns of isozymes were detected by immunohistochemistry. CAII and CIX expression levels were lower in the squamous epithelium than in the columnar cells while CAXII showed an opposite pattern and was present mainly in squamous epithelium. Expression patterns in benign, dysplastic, or malignant esophageal columnar lesions were not significantly different. The assessment of clinicopathological associations showed that CAII was significantly downregulated in metastatic disease (p = 0.026). CAIX showed no association with prognosis, although there appeared to be an association (p = 0.056) between high expression and nodal spread. In conclusion, CAII, CAIX, and CAXII do not serve as biomarkers for different phases in the development of EAC.