ABSTRACT
PURPOSE: Hypoxia is common in many solid tumors such as breast, head-neck, and soft tissue malignancies. Hypoxia causes overexpression of hypoxia inducible factor-1 alpha (HIF-1α) and carbonic anhydrase IX (CA IX) which are associated with unfavorable prognosis in breast cancer. In our study, we evaluated HIF-1α and CA IX expression in patients with breast cancer. METHODS: Between June 1996 and June 2008, 111 women with breast cancer were evaluated. Estrogen receptor (ER) and progesterone receptor (PR) status and Her2/ neu expression were evaluated by immunohistochemical methods. Her-2/neu expression was also assessed by FISH method when needed. Two groups were created: ER and PR positive, Her-2/neu negative (group 1, n=56); and ER and PR negative, Her-2/neu positive (group 2, n=55). HIF-1α and CA IX expressions were investigated in both groups and results were compared. In addition, we investigated the association between HIF-1α and CA IX expressions with stage, grade, lymph node metastasis, tumor size, menopause status and survival. RESULTS: Median patient age in group 1 was 52 years (range 34-77), and in group 2 47 years (range 27-83). HIF-1α expression was detected in 26 (46.4%) of group 1 and in 46 (83.6%) of group 2 patients (p=0.0001). CA IX expression was detected in 25 (46.4%) of group 1 and in 37 (67.3%) of group 2 patients (p7equals;0.0137rpar;. In group 1, median disease free survival (DFS) was 97 months and in group 2 46 months (p=0.0308). In group 1, median overall survival (OS) was 108 months and in group 2 75 months (p=0.0339). CONCLUSION: HIF-1α and CA IX overexpressions are observed more often in ER and PR negative, Her-2/neu positive breast cancer and are associated with poor survival.
