Figure 4

Systemic Chol-let-7a therapy modulated ras /RAS abundance in HCC orthotopic xenografts. A: Let-7a expression in HepG2 orthotopic xenografts was examined by quantitative real-time PCR. Relative quantification of let-7a was calculated using the comparative cycle threshold (CT) method (2 ^ΔΔct) with let-7a normalized to U6. The results shown represent the mean and standard error from 3 independent experiments, *p <0.05, **p <0.01 in comparison with controls. T-test: Chol-let-7a vs. Chol-miRCtrl, p = 0.008; Chol-let-7a vs. blank, p = 0.013; Chol-miRCtrl vs. blank, p = 0.128. B: RAS protein expression in xenografts examined by western blotting. KRAS, HRAS, and NRAS protein expression was measured in xenografts by western blotting. Representative data are shown from 2 experiments. C: qRT-PCR analysis of ras mRNA in xenografts. Relative quantification of target genes was calculated using the comparative cycle threshold (CT) method (2 ^ΔΔct) with genes normalized to GAPDH. The results shown represent the mean and standard error from 3 independent experiments.*p <0.05, ** p <0.01 in comparison with controls. Analysis revealed deregulated expression of k-ras, h-ras, and n-ras mRNA. T-test: n-ras (Chol-let-7a vs. Chol-miRCtrl, p = 0.002; Chol-let-7a vs. blank, p = 0.002; Chol-miRCtrl vs. blank, p = 0.837); h-ras (Chol-let-7a vs. Chol-miRCtrl, p = 0.016; Chol-let-7a vs. blank, p = 0.033; Chol-miRCtrl vs. blank, p = 0.801); and k-ras (Chol-let-7a vs. Chol-miRCtrl, p = 0.041; Chol-let-7a vs. blank, p = 0.005; Chol-miRCtrl vs. blank, p = 0.84).