Fig. 3.

GNAS knockdown inhibits LPS-induced IL-6 expression by suppressing STAT3 activation in HCC cells. a HepG2 cells were transfected with si-NC or si-GNAS for 24 h and then treated with LPS (5 μg/ml) or not for the indicated hours. Then, the protein expression levels of p65, phosphorylated p65 (p-p65), and GNAS were detected by Western blotting. b HepG2 cells were transfected with pCMV-myc vector or pCMV-myc-GNAS for 24 h, and then treated with the specific inhibitor of NF-kB, PDTC, for 30 min. IL-6 mRNA expression levels were detected by qRT-PCR. c HepG2 cells were transfected with si-NC or si-GNAS for 24 h and then treated with LPS or MED for 30 min. Transcription factors activation profiling plate array was performed. d HepG2 cells were transfected with pCMV-myc vector or pCMV-myc-GNAS for 24 h, and then treated with a specific inhibitor of STAT3, c188–9, for 30 min. IL-6 mRNA expression levels were detected by qRT-PCR. e HepG2 cells were transfected with si-NC or si-GNAS for 24 h and then treated with LPS or MED for 30 min. STAT3 binding on IL-6 promoter was detected by ChIP assay. f HepG2 cells were transfected with si-NC or si-GNAS for 24 h and then treated with LPS (5 μg/ml) or not for the indicated hours. Then, the protein expression levels of STAT3, phosphorylated STAT3 (p-STAT3), and GNAS were detected by Western blotting. Data are represented as means ± SD (n = 3; ^*represents P < 0.05)