Alteration of TLR4 influences LPS-induced metastasis and EMT of HCC cells. (A) and (B) HepG2 cells were transduced with adeno-associated virus to express TLR4 and SMMC-7721 cells were transduced with siRNA to knocked down TLR4, and then the cells were treated with LPS. The migration of pretreated HCC cells was determined by the wound healing assay (A, × 200) and the invasiveness of pretreated HCC cells was determined by the Transwell assay (B, × 200). (C) Expression of EMT genes in pretreated HCC cells was detected by qPCR (normalized to β-actin) Results presented represent the mean of triplicate experiments ± SEM (*P < 0.05, **P < 0.01). (D) Pictures of metastatic liver nodules in nude mice by splenic-vein injection of pretreated HCC cells (× 200). The arrows indicate the metastatic tumor on the surface of the liver (n = 10 per group). (E) and (F) The number of nodules was quantified on nude mice livers by splenic-vein injection of pretreated HCC cells. Values for individual mice are shown above the bars (*P < 0.05). EMT, epithelial-mesenchymal transition; HCC, hepatocellular carcinoma; LPS, lipopolysaccharide; SEM, standard error of the mean; TLR4, toll-like receptor 4.