Polo-like kinase 1, a new therapeutic target in hepatocellular carcinoma

Figure 1 Upregulation of polo-like kinase 1 gene expression in 56 hepatocellular carcinoma tumors, efficiency of short-interfering RNA in silencing the polo-like kinase 1 gene, and protein expression in Huh-7 cells. A: Boxplot showing the minimum, 25th percentile, median, 75th percentile and maximum relative polo-like kinase 1 (PLK1) gene expression. Circles represent statistical outliers. PLK1 gene expression in all hepatocellular carcinoma (HCC) tissue was quantified relative to the non-tumor tissue counterpart using the 2^-∆∆Ct method; B: Knockdown with short interfering PLK1 (si-PLK1) at 1 nmol/L, 50 nmol/L and 100 nmol/L successfully silenced PLK1 gene expression (using the 2^-∆∆Ct method by quantitative real-time RT-PCR) by 83%, 95% and 96% respectively, compared with short interfering non-targeting (si-NT), or controls. Data shown as mean ± SE, using the Student t-test (^aP < 0.05); C: Western blotting showing reduction of PLK1 protein expression in Huh-7 cells, at si-PLK1 and si-NT (non-targeting si-RNA) concentrations of 50 nmol/L compared with si-NT or controls.