Figure 5

Effects of IFN-β on RCC growth. (a) Twenty-four hours after poly(I:C) transfection, cells were harvested and real-time PCR was performed to examine IFN-α and IFN-β mRNA expression. Relative mRNA levels are shown relative to those of β-actin. **p < 0.01. (b) RCC lines were co-cultured with human IFN-β, and cell viability was determined using the WST-8 assay after 24 h. **p < 0.01. (c) Similarly, after culturing with human IFN-β (1,000 U/ml), an apoptosis assay was performed using Annexin V and PI staining. Numbers represent the percentages of each subset. Similar results were obtained from three independent experiments. (d) Both cell lines were cultured or transfected with poly(I:C) (SKRC-1, 100 ng/ml; SKRC-44, 50 ng/ml) for 48 h. Cells were then cultured with BrdU (10 μM) during the last 90 min for SKRC-1 and 6 h for SKRC-44. After staining with FITC-conjugated anti-BrdU and 7-AAD, cells were analyzed by flow cytometry. Numbers represent the percentages for each cell cycle phase. Similar results were obtained from two independent experiments. (e) Levels of cyclinD1, c-Myc and p21 were examined by immunoblotting kinetically after poly(I:C) transfection. β-actin was used as a control. Similar results were obtained from two independent experiments. pIC-TF, poly(I:C) transfection.