Fig 1: Protein expression of CA I, II, IX, and XII isoforms in MCF-7 and SK-BR-3 cells. (A) MCF-7 and (B) SK-BR-3 cells were exposed to vehicle or CoCl2 (100 µM) for 48 h. Protein levels of CA isoforms were determined by western blotting analyses using anti-CA I, II, IX, and XII antibodies, respectively. ß-Actin was used for normalization. The expression level of each isoform in CoCl2-treated cells (black bar) is expressed as a percentage of the respective control measured in the vehicle (DMSO)-treated cells without CoCl2 (white bar). Representative blots are shown. Data are displayed as mean ± SEM from three independent experiments. * p < 0.05 vs. the vehicle-treated control cells.