Fig 2: Knockdown of CK1a increased HCV core protein-induced cell apoptosis. (A) Cell apoptosis was measured by flow cytometry combined with Annexin V-fluorescein isothiocyanate/propidium iodide staining in control and CK1a knockdown cells. (B) Western blot analysis for the expression status of Bid and caspase-8 in control and CK1a knockdown cells that transfected with different HCV core proteins. HCV, hepatitis C virus; CK1, casein kinase 1; Bid, BH3 interacting-domain death agonist; NC, negative control; T, core proteins derived from tumor tissues; NT, core proteins derived from non-tumor tissues; C191, core proteins from the HCV-J6 strain.

Fig 3: Successful construction of stable CK1a knockdown Huh-7 cells. (A) mRNA and (B) protein levels of CK1a among mock, NC and CK1a knockdown Huh-7 cells. (C) Cellular morphology of Huh-7 cells in different groups (magnification, ×100). **P<0.01 vs. mock. HCV, hepatitis C virus; CK1, casein kinase 1; NC, negative control.

Fig 4: Knockdown of p53 increased HCV core protein and TRAIL-induced cell apoptosis. (A) Cell apoptosis in Huh-7 cells that were transfected with control siRNA or p53 siRNA was measured by electron microscopy. Scale bars, top row=2 µm; bottom row=500 µm. (B) Western blot analysis for the expression level of Bid in control and p53 knockdown cells that were transfected with different HCV core proteins. HCV, hepatitis C virus; TRAIL, tumor necrosis factor-related apoptosis-inducing ligand; CK1, casein kinase 1; Bid, BH3 interacting-domain death agonist; NC, negative control; siRNA, small interfering RNA; RNAi, RNA interference.

Fig 5: Knockdown of CK1a increased different HCV core proteins and TRAIL-induced cell apoptosis. (A) Cell apoptosis was tested by flow cytometry in control cells and CK1a knockdown cells that were induced by TRAIL (A). (B) Western blot analysis for the expression of Bid, p53 and PCNA in control and CK1a knockdown cells. (C) CHIP-PCR amplification demonstrated binding of p53 to the promoter regions of human Bid in Huh-7 cells. PCR was performed in input, p21-positive controls and IgG negative controls. (D) The quantitative PCR method was carried out for detecting the CHIp. TRAIL, tumor necrosis factor-related apoptosis-inducing ligand; HCV, hepatitis C virus; CK1, casein kinase 1; CHIP-PCR, chromatin immunoprecipitation-polymerase chain reaction; Bid, BH3 interacting-domain death agonist; NC, negative control; T, core proteins derived from tumor tissues; NT, core proteins derived from non-tumor tissues; C191, core proteins from the HCV-J6 strain; PCNA, proliferating cell nuclear antigen.