Carbonic anhydrase IX expression, a novel surrogate marker of tumor hypoxia, is associated with a poor prognosis in non-small-cell lung cancer.
Swinson DEB., Jones JL., Richardson D., Wykoff C., Turley H., Pastorek J., Taub N., Harris AL., O'Byrne KJ.
PURPOSE: To evaluate carbonic anhydrase (CA) IX as a surrogate marker of hypoxia and investigate the prognostic significance of different patterns of expression in non-small-cell lung cancer (NSCLC). METHODS: Standard immunohistochemical techniques were used to study CA IX expression in 175 resected NSCLC tumors. CA IX expression was determined by Western blotting in A549 cell lines grown under normoxic and hypoxic conditions. Measurements from microvessels to CA IX positivity were obtained. RESULTS: CA IX immunostaining was detected in 81.8% of patients. Membranous (m) (P =.005), cytoplasmic (c) (P =.018), and stromal (P