Cells with reduced CDC25B level are delayed in G2/M transition. Hep3B and Hep40 cells were transfected with siRNA2-CDC25B, siRNA-N or RNAiMAX for 48 hours. Cell cycle distribution was determined by flow cytometry. A. Representative set of histograms for transfected and control cells. B. Percentage of cells in G2 stage. Columns, mean of at least three independent experiments; bars, SD; P < 0.05 for siRNA2-CDC25B versus siRNA-N transfected cells.