ABSTRACT
Objective The TLR4 signaling pathway may be involved in the development and progression of hepatocarcinoma . This study aimed to investigate the effect of inhibiting the TLR 4 signaling pathway on the orthotopic implanted liver tumor (OILT) in mice. Methods A TLR4-silencing siRNA lentiviral vector was constructed and transfected into mouse hepatoma H 22 cells.Mouse hepatoma H22 cells were divided into groups A (blank control), B (empty vector) and C (siRNA lentiviral vector), those in group A left untreated and those in groups B and C infected with an empty vector and the TLR 4-silencing siRNA lentiviral vector , respectively. The volumes of the OILTs in different groups measured and the expressions of TLR 4, MyD88, NF-κB and TRAM in the tumor cells de-termined by immunohistochemistry and Western blot . Results The OILT volume was significantly reduced in group C than in A and B ([568.3±90.3] vs [1303.0±194.1] and [1385.0±137.0] mm3 , P<0.05), and so were the expressions of TLR4, MyD88, NF-κB and TRAM in the tumor cells (P<0.05). Conclusion Down-regula-ting the TLR4 signaling pathway can suppress the growth of the ortho -topic implanted liver tumor in mice, which may be associated with the activation of NF-κB by the MyD88-dependent signaling pathway and that of TRAM by the MyD88-independent signaling pathway .