Fig. 4. Effect of PKM2 siRNA transfection on cellular metabolite levels in DU145 cells. (A) Quantitative level of pyruvate in the lysates and media of the PKM2 siRNA-transfected cells (100nM for 72 h). (B) Effect of lactate level in the PKM2 knockdown cells (100 nM of siRNAs for 72 h). One-way ANOVA was used to compare the means of the different groups. Differences between the means were considered to be significant at P<0.05 by using the Tukey multiple comparison tests; ^*P<0.05, **P<0.01, and ***P<0.001 compared with the normal control cells.