Prognostic significance of carbonic anhydrase IX expression by cancer-associated fibroblasts in lung adenocarcinoma.

Background: Cancer tissue is comprised of cancer cells and several types of stromal cells, including cancer-associated fibroblasts (CAFs). Carbonic anhydrase (CA) IX has been used as an endogenous hypoxia marker, and although its expression by cancer cells has been reported to be associated with a poor outcome in a board range of tumors, to the authors' knowledge, the biologic significance of its expression by CAFs remains unclear.

Methods: The authors investigated CA IX expression by CAFs and cancer cells immunohistochemically in 158 consecutive resected cases of lung adenocarcinoma.

Carbonic anhydrase IX expression is associated with tumor progression and a poor prognosis of lung adenocarcinoma.

Carbonic anhydrase (CA) IX catalyzes the hydration of carbon dioxide into carbonic acid and participates in a variety of physiological and biological processes. The aim of this study was to evaluate the prognostic significance of CA IX expression in patients with lung adenocarcinoma. Standard immunohistochemical techniques were used to study CA IX expression in 134 patients who underwent curative resection for adenocarcinoma of the lung at our hospital between January 1995 and December 1996.