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Background: Recent studies have demonstrated that synthetic dsRNAs may produce therapeutic effects in a target-independent manner through stimulation of the toll-like receptor-3 (TLR3)/interferon pathway; as a result, angiogenesis and proliferation of tumor cells are inhibited. Thus, this pathway may become a potential target of dsRNA in tumor suppression. In this study, we evaluated the role of synthetic dsRNA as a TLR3 synergist and by combining with sorafenib in anti-hepatocellular carcinoma (HCC) in vitro and in vivo.Methods: Four dsRNAs were designed and synthesized. One of them that was capable of activating TLR3 most effectively in human HCC cell line (HepG2.2.15) was selected as a TLR3 synergist (called BM-06). Subsequently, the expression of proteins relating to TLR3 signaling pathway, such as NF-κB, caspase 8 survivin, bcl-2 and PCNA affected by BM-06, sorafenib alone or in combination, was compared. The migration, proliferation and apoptosis of HepG2.2.15 cells were evaluated in presence of BM-06, sorafenib alone or in combination of both. The similar treatments were also applied in an SD rat primary HCC model.Results: qRT-PCR data showed that the expression of TLR3 and NF-κB in HepG2.2.15 cells was enhanced. BM-06 was selected as a TLR3 synergist capable of activating the TLR3/interferon pathway most effective among 4 synthetic dsRNAs. The migration and proliferation were significantly inhibited in treated HepG2.2.15 cells with BM-06 or Sorafenib alone as compared with PBS-sham control (P<0.01). However, the role of combination BM-06 with Sorafenib was the most prominent. Tumor cell apoptotic rate was increased by BM-06 or combination when compared to PBS or poly(I:C) (P<0.05). Similarly, in orthotopic HCC SD rats, the effect of the combination was superior to either agent alone on the inhibition of tumor growth and induction of HCC cell apoptosis (P<0.05).Conclusions: dsRNA alone was capable of inhibiting the proliferation of HepG2.2.15 cells and tumor growth of orthotopic HCC SD rats, but the effect of combination of dsRNA with sorafenib was more prominent. These findings implicate the potential role of combined use of a dsRNA, a TLR3 synergist, and sorafenib in inhibition of HCC. [ABSTRACT FROM AUTHOR]

Background: A role for autophagy, a conserved cellular response to stress, has recently been demonstrated in human cancers. Aberrant expression of Beclin-1, an important autophagic gene, has been reported in various human cancers. In the present study, we investigated the significance and relationship between Beclin-1 expression and cell proliferation, apoptosis, microvessel density (MVD) and clinical pathological changes or prognosis in human hepatocellular carcinoma (HCC).Methods: A total of 103 primary HCC patients were involved in the study. Expression of Beclin-1, PCNA, NET-1, Bcl-2, Bax, Survivin in cancer cells and CD34 in stromal microvessels were evaluated immunohistochemically in tissue microarrays comprising 103 cases of HCC and 57 matched adjacent nontumor liver tissues. Correlations between clinicopathological characteristics and survival of HCC patients were explored.Results: The positive rate of Beclin-1 was significantly lower in HCC tissues than adjacent tissues (72.8 vs. 89.5%, χ2 = 6.085, P = 0.015). In HCC, Beclin-1 expression was negatively correlated with cirrhosis background (r = -0.216, P = 0.029), Edmondson grade (r = -0.249, P = 0.011), vascular invasion (r = -0.246, P = 0.012), PCNA (r = -0.242, P = 0.014), NET-1 (r = -0.245, P = 0.013), anti-apoptosis protein Bcl-2 (r = -0.245, P = 0.013) and MVD (r = -0.292, P = 0.003), and positively correlated with pro-apoptosis protein Bax (r = 0.242, P = 0.014).Significant differences in the 5-year survival rates were seen among patients with Beclin-1 strong positive (++) (59.1%, 13/22), moderate positive (+) (28.3%, 15/53) and weak negative expression (-) (14.6%, 7/28) (P = 0.043). Significant differences were detected between Beclin-1 (++) and either Beclin-1 (+) (P = 0.036) or Beclin-1 (-) groups (P = 0.008), but no significant difference between Beclin-1 (+) and Beclin-1 (-) groups (P = 0.281) was observed.Survival rates were positively related to high Beclin-1 co-expressed with low PCNA, NET-1, or Bcl-2, lower MVD, and high Bax. Univariate and multivariate Cox regression analysis revealed that Beclin-1 expression was an independent indicator for overall survival in HCC patients (P < 0.05).Conclusions: The pathogenesis and progression of HCC are associated with reduced autophagy. The expression of Beclin-1 and Bax in HCC tissues may provide a synergistic effect towards inhibiting HCC proliferation, infiltration, metastasis and angiogenesis. Beclin-1 expression may be a valuable prognostic marker of HCC. [ABSTRACT FROM AUTHOR]