Figure 5. miR-155 is a negative regulator of TLR3 expression. (A) Spearman's correlation analysis of the relationship between TLR3 and miR-155 levels in HCC tissues. (B) Analysis of miR-155 and TLR3 expression by qRT-PCR in HepG2 cell transfected with miR-155 mimics. (C) qRT-PCR analysis of TLR3 expression in HepG2 cells transfected with control siRNA (si-NC) or with 3 siRNA variants targeting TLR3. (D) Detection of miR-155 and NF-κB by qRT-PCR in HepG2 cells transfected with si-2-TLR3. (E, F) Results of cell viability (MTT) and apoptosis (Annexin V-FITC) assays conducted in HepG2 cells transfected with si-2-TLR3 or si-NC. (G) Quantification of TLR3 mRNA levels in HepG2 cells following si-2-TLR3-mediated TLR3 knockdown with or without concurrent miR-155 inhibition. Data are presented as the mean ± SD; n = 3 biologically independent samples. *P<0.05, **P<0.01; ns, no significant difference (Student’s t-test).