Clinical efficacy of current therapies for hepatocellular carcinoma (HCC) treatment is limited. Indole-3-acetic acid (IAA) is non-toxic for mammalian cells. Oxidative decarboxylation of IAA by horseradish peroxidase (HRP) leads to toxic effects of IAA. The purpose of this study was to investigate the effects of a novel gene-targeted enzyme prodrug therapy with IAA on hepatoma growth in vitro and in vivo mouse hepatoma models. We generated a plasmid using adenovirus to express HRP isoenzyme C (HRPC) with the HCC marker, alpha-fetoprotein (AFP), as the promoter (pAdv-AFP-HRPC). Hepatocellular cells were infected with pAdv-AFP-HRPC and treated with IAA. Cell death was detected using MTT assay. Hepatoma xenografts were developed in mice by injection of mouse hepatoma cells. The size and weight of tumors and organs were evaluated. Cell death in tumors was assessed using hematoxylin and eosin-stained tissue sections. HRPC expression in tissues was detected using Reverse Transcriptase-Polymerase Chain Reaction. IAA stimulated death of hepatocellular cells infected with pAdv-AFP-HRPC, in a dose-and time-dependent manner, but not in control cells. Growth of hepatoma xenografts, including the size and weight, was inhibited in mice treated with pAdv-AFP-HRPC and IAA, compared with that in control group. pAdv-AFP-HRPC/IAA treatment induced cell death in hepatoma xenografts in mice. HRPC gene expressed only in hepatoma, but not in other normal organs of mice. pAdv-AFP-HRPC/IAA treatment did not cause any side effects on normal organs. These findings suggest that pAdv-AFP-HRPC/IAA enzyme/prodrug system may serve as a strategy for HCC therapy.

Murine b-defensin 2 (MBD2) is not only chemotactic for immature dendritic cells but also activates them by Toll-like receptor 4. We have previously demonstrated that vaccine with MBD2 elicited potent antileukemia responses in the L1210 murine model. Interleukin-18 (IL-18) is an essential cytokine for the generation of Th1 response and natural killer cells and cytotoxic T lymphocytes (CTL) activation. As MBD2 and IL-18 appear to function on different components required by an effective antitumor immune response including both innate and adaptive immunity, we investigated whether combinatorial delivery of MBD2 and IL-18 transduced L1210 cells could elicit synergistic antileukemia effects. First, we constructed a single plasmid vector carrying both pro-IL-18 and IL-1b converting enzyme (ICE) genes, and found that transfection of this vector into L1210 cells resulted in efficient secretion of bioactive IL-18. Combinatorial delivery of MBD2 and pro-IL-18-ICE modified L1210 cells conferred a superior inhibition of leukemogenicity over either L1210-MBD2 or L1210-pro-IL-18-ICE alone; moreover, the survived mice developed long-lasting protective immunity as determined by rechallenge experiments. This combined vaccine also elicited the most marked therapeutic effect, CTL activity and interferon-g production. These results suggest that the combination of MBD2 and IL-18 induces more effective antileukemia activity and provides a promising strategy for cancer therapy.

Rabies virus (RABV) is known to cause a fatal infection in many mammalian species, yet its pathogenesis remains poorly understood. This study was performed to analyze the microRNA (miRNA) expression profiles in RABV-infected primary neurons of mice. A total of 53 miRNAs were found to be differentially expressed in RABV-infected samples compared with mock samples in a time-dependent manner. Among them, the expression of ten miRNAs was validated by real-time RT-PCR. Potential target genes of differentially expressed miRNAs were predicted by TargetScan. Further bioinformatics analysis indicated that these predicted targets were overrepresented in neuronal function-related Gene Ontology (GO) terms and biological pathways. The results of this study suggest that RABV may cause neuronal dysfunction by regulating cellular miRNA expression.

ABSTRACT. We conducted a case-control study to investigate the role of three common single nucleotide polymorphisms of IL-10 (-592G/A, -819T/ C, and -1082A/C) in the development of hepatitis B virus (HBV)-related hepatocellular carcinoma (HCC). The study included 173 HBV-related HCC patients and 182 healthy controls. A polymerase chain reaction-restriction fragment length polymorphism assay was applied to assess the sequence variants of interest. Compared with control subjects, HCC patients were more likely to be older (t = 1.94, P = 0.03), have a family history of cancer (chi square = 17.86, P < 0.001), and exhibit higher alanine transaminase (t = 13.32, P < 0.001) and aspartate transaminase (t = 12.63, P < 0.001) levels. Using unconditional logistic regression analyses, we found that the GG genotype of -592G/A was associated with increased risk of HCC [odds ratio (OR) = 2.20, 95% confidence interval (CI) = 1.12-4.38], compared to the AA genotype. Under a dominant model, the AG+GG genotype correlated with HBV-related HCC susceptibility compared to the AA genotype, with an OR (95%CI) of 1.56 (1.02-2.48). Moreover, a recessive model showed the GG genotype to be associated with elevated risk of HCC compared to the AA+AG genotype (OR = 1.85, 95%CI = 1.01-3.47). However, no significant association between the -819T/C and -1082A/C variants and development of HBV-related HCC was observed under codominant, dominant, and recessive models. We conclude that the IL-10 -592G/A polymorphism does play a role in susceptibility to HBV-related HCC under codominant, dominant, and recessive models.