title: Carbonic anhydrase-9 expression levels and prognosis in human breast cancer: association with treatment outcome.
abstract: Here, we set out to assess CA9 expression levels by real-time quantitative RT-PCR in breast cancer tissue samples obtained from 253 patients, and correlated those with relapse-free (RFS) survival. The median follow-up time was 75 months (range 2-168 months). CA9 expression was mainly found in high-grade, steroid receptor negative cancer tissues. CA9 levels were not significantly associated with RFS (P=0.926, hazard ratio (HR)=0.99, 95% CI=0.80-1.22) in the total cohort of 253 patients. In multivariate analysis with other clinicopathological factors, CA9 (P=0.018, HR=0.77, 95% CI=0.62-0.96), the interaction of adjuvant chemotherapy with CA9 (P=0.009, HR=1.31, 95% CI=1.07-1.61) and the interaction of adjuvant endocrine therapy with CA9 (P<0.001, HR=1.41, 95% CI=1.20-1.66) all contributed significantly to the final model. These results indicate that patients with low CA9 levels benefit more from adjuvant treatment than do patients with high levels. Thus, the determination of CA9 levels could aid in the selection of patients who will not benefit from adjuvant therapy, and whose prognosis will more likely improve with other treatment modalities.
authors.affiliation: Department of Chemical Endocrinology, University Medical Centre Nijmegen, Nijmegen, The Netherlands. p.span@ace.umcn.nl
authors.forename: P N
authors.initials: PN
authors.lastname: Span
authors.forename: J
authors.initials: J
authors.lastname: Bussink
authors.forename: P
authors.initials: P
authors.lastname: Manders
authors.forename: L V A M
authors.initials: LV
authors.lastname: Beex
authors.forename: C G J
authors.initials: CG
authors.lastname: Sweep
mesh_terms: D000951:Antigens, Neoplasm / Q000032:analysis*; D018931:Antineoplastic Agents, Hormonal / Q000494:pharmacology; D014408:Biomarkers, Tumor / Q000032:analysis*; D001943:Breast Neoplasms / Q000473:pathology* / Q000628:therapy*; D000071231:Carbonic Anhydrase IX; D002256:Carbonic Anhydrases / Q000032:analysis*; D017024:Chemotherapy, Adjuvant; D004273:DNA, Neoplasm; D018572:Disease-Free Survival; D019008:Drug Resistance, Neoplasm; D005260:Female; D005500:Follow-Up Studies; D015972:Gene Expression Regulation, Neoplastic; D006801:Humans; D007150:Immunohistochemistry; D007527:Isoenzymes; D015411:Mastectomy, Modified Radical; D009363:Neoplasm Proteins / Q000032:analysis*; D011237:Predictive Value of Tests; D011379:Prognosis; D018714:Radiotherapy, Adjuvant; D011987:Receptors, Steroid / Q000032:analysis; D020133:Reverse Transcriptase Polymerase Chain Reaction; D016019:Survival Analysis
chemical_list: D000951:Antigens, Neoplasm; D018931:Antineoplastic Agents, Hormonal; D014408:Biomarkers, Tumor; D004273:DNA, Neoplasm; D007527:Isoenzymes; D009363:Neoplasm Proteins; D011987:Receptors, Steroid; C089226:CA9 protein, human; D000071231:Carbonic Anhydrase IX; D002256:Carbonic Anhydrases