Erratum: Role of ursolic acid chalcone, a synthetic analogue of ursolic acid, in inhibiting the properties of CD133(+) sphere-forming cells in liver stem cells.

[This corrects the article on p. 1427 in vol. 8, PMID: 25973027.].

Mefloquine targets ß-catenin pathway and thus can play a role in the treatment of liver cancer.

The current study was designed and performed to investigate the effect of mefloquine on the proliferation and tumor formation potential of liver cancer stem cells. CD133 + HepG2 cells were identified using MACS and showed markedly higher tumor formation potential compared to the parental cells. The secondary tumors formed by CD133 + cells were markedly large in size and more in number compared to the parental cells. Mefloquine treatment of CD133 + HepG2 cells inhibited the proliferation selectively in concentration based manner. The rate of proliferation was inhibited to 82 and 12% in parental and CD133 + sphere forming cells, respectively on treatment with 10 µM concentration of mefloquine. The number of secondary tumors formed by primary tumors was decreased significantly on treatment with 10 µM mefloquine concentration. Treatment of the liver cancer stem cells with mefloquine markedly decreased the potential to undergo self-renewal at 10 µM concentration after 48 h. The results from western blot analysis showed significantly higher expression of cancer stem cell molecules ß-catenin and cyclin D1 in LCSCs. Treatment of the LCSCs with various concentrations of mefloquine reduced the expression levels of ß-catenin and cyclin D1. Administration of the CD133 + cell tumor xenografts in the mice led to the formation of large sized tumors in the control group. However, the tumor growth was inhibited significantly in the mice on treatment with 10 mg/kg doses of mefloquine after day 21. The tumor weight was significantly lower in the animals of mefloquine treatment group compared to the control group. Thus, mefloquine treatment inhibits self-renewal and proliferation potential of cells through targeting ß-catenin pathway.

Correlations of IFN-γ-inducible protein-10 with the risk of chronic hepatitis B and the efficacy of interferon therapy in Asians.

PURPOSE: The aim of this study was to identify the correlations of IFN-γ-inducible protein-10 (IP-10) with the risk of chronic hepatitis B (CHB) and the efficacy of interferon therapy in Asians. METHOD: Serum IP-10 levels were assayed using enzyme linked immunosorbent assay (ELISA) in both CHB and control group. CHB group received interferon-α2b treatment to compare the pre-treatment and post-treatment serum IP-10 levels. Relevant studies met predefined inclusion and exclusion criteria were enrolled into further meta-analysis. Stata 12.0 software was applied for data analysis. RESULT: Our case-control study demonstrated that CHB group had evaluated serum IP-10 levels compared with control group (285.7 ± 41.6 pg/mL vs. 79.1 ± 33.8 pg/mL, t = 21.85, P < 0.001. After treatment for 12 weeks, CHB group had remarkably decreased post-treatment serum IP-10 levels than pre-treatment (78.5 ± 20.4 pg/mL vs. 285.7 ± 41.6 pg/mL, t = 33.76, P < 0.001). No significance was observed on post-treatment serum IP-10 levels between CHB and control group (78.5 ± 20.4 pg/mL vs. 78.1 ± 33.8 pg/mL, t = 0.07, P = 0.947). Meta-analysis results demonstrated that serum IP-10 levels in CHB group were obviously higher than healthy controls (SMD = 2.21, 95% CI = 1.55~2.87, P < 0.001). A subgroup based on the HBeAg states revealed that serum IP-10 levels in both HBeAg-positive and HBeAg-negative CHB patients were notably higher than healthy controls (HBeAg-positive: SMD = 2.00, 95% CI = 1.13-2.87, P < 0.001; HBeAg-negative: SMD = 1.34, 95% CI = 0.97-1.72, P < 0.001). CONCLUSION: Serum IP-10 may be correlated with the risk of CHB and the efficiency of interferon therapy, thus IP-10 may be a good biomarker for the diagnosis and treatment of CHB.

Regulation of T cell function by microRNA-720.

Chronic hepatitis B virus (HBV) infection is a major global health burden. Functional exhaustion and numerical reduction of HBV-specific cytotoxic T lymphocytes (CTLs) in the liver and peripheral blood limit anti-HBV CTL activity in patients with chronic HBV infection (CHB). However, the ongoing anti-HBV CD8(+) T cell responses in the lymphoid organs are largely unknown due to the infeasibility of obtaining lymphoid organs from CHB patients. Here we demonstrate that the percentage of HBV-specific CD8(+) T cells is higher in the spleen of CHB patients than that from peripheral blood and liver. Although they do respond to TCR stimulation and produce IFNγ, the cells proliferate poorly. Furthermore, miR-720 expression is upregulated in HBV-specific CD8(+) T cells. Overexpression of miR-720 in primary human CD8(+) T cells inhibits TCR stimulation-induced proliferation. We also demonstrate that TGFß sustains miR-720 upregulation after TCR stimulation, and blood TGFß levels are associated with the outcome of type I interferon treatment of CHB patients. Thus, therapies targeting miR-720 may help restore impaired immunity in CHB patients.

Role of ursolic acid chalcone, a synthetic analogue of ursolic acid, in inhibiting the properties of CD133(+) sphere-forming cells in liver stem cells.

The expression of CD133 decreases with differentiation of tumor cell, indicating that CD133 is a specific marker for isolation and identification of CSCs. In the present study the effect of Ursolic acid chalcone (UAC) on CD133(+) hepatocellular carcinoma cell (HCC CSCs) differentiation, their self-renewal, tumorigenic capacity and sensitivity to chemotherapeutic drugs was studied. The results demonstrated that UAC inhibits the expression of CD133(+) in a dose and time-dependent manner in PLC/PRF/5 and Huh7 HCC cells. The inhibition was significant at 50 µM and on day 8. The percentage of CD133(+) cells decreased from an initial 59.3% in PLC/PRF/5 to 37.1% and 78.2% in Huh7 to 59.2% on treatment with UAC. There was inhibition of Oct4, Tert, Bmi1, ß-catenin, ABCG2, and tumor sphere-related gene Ep300. In addition it also decreased number of CK19-positive cells and increased number of CK8/18-positive cells. UAC treatment caused a decrease in self-renewal capability and increase in sensitivity to doxorubicin and vincristine drugs in CD133(+) HCC CSCs. Therefore, UAC can be a potent therapeutic agent to target differentiation of CSC in HCC.

Regulation of T cell proliferation by JMJD6 and PDGF-BB during chronic hepatitis B infection.

T cell functional exhaustion during chronic hepatitis B virus (HBV) infection may contribute to the failed viral clearance; however, the underlying molecular mechanisms remain largely unknown. Here we demonstrate that jumonji domain-containing protein 6 (JMJD6) is a potential regulator of T cell proliferation during chronic HBV infection. The expression of JMJD6 was reduced in T lymphocytes in chronic hepatitis B (CHB) patients, and this reduction in JMJD6 expression was associated with impaired T cell proliferation. Moreover, silencing JMJD6 expression in primary human T cells impaired T cell proliferation. We found that JMJD6 promotes T cell proliferation by suppressing the mRNA expression of CDKN3. Furthermore, we have identified platelet derived growth factor-BB (PDGF-BB) as a regulator of JMJD6 expression. PDGF-BB downregulates JMJD6 expression and inhibits the proliferation of human primary T cells. Importantly, the expression levels of JMJD6 and PDGF-BB in lymphocytes from CHB patients were correlated with the degree of liver damage and the outcome of chronic HBV infection treatment. Our results demonstrate that PDGF-BB and JMJD6 regulate T cell function during chronic HBV infection and may provide insights for the treatment strategies for CHB patients.

A novel antibody humanization method based on epitopes scanning and molecular dynamics simulation.

1-17-2 is a rat anti-human DEC-205 monoclonal antibody that induces internalization and delivers antigen to dendritic cells (DCs). The potentially clinical application of this antibody is limited by its murine origin. Traditional humanization method such as complementarity determining regions (CDRs) graft often leads to a decreased or even lost affinity. Here we have developed a novel antibody humanization method based on computer modeling and bioinformatics analysis. First, we used homology modeling technology to build the precise model of Fab. A novel epitope scanning algorithm was designed to identify antigenic residues in the framework regions (FRs) that need to be mutated to human counterpart in the humanization process. Then virtual mutation and molecular dynamics (MD) simulation were used to assess the conformational impact imposed by all the mutations. By comparing the root-mean-square deviations (RMSDs) of CDRs, we found five key residues whose mutations would destroy the original conformation of CDRs. These residues need to be back-mutated to rescue the antibody binding affinity. Finally we constructed the antibodies in vitro and compared their binding affinity by flow cytometry and surface plasmon resonance (SPR) assay. The binding affinity of the refined humanized antibody was similar to that of the original rat antibody. Our results have established a novel method based on epitopes scanning and MD simulation for antibody humanization.

T lymphocytes from chronic HCV-infected patients are primed for activation-induced apoptosis and express unique pro-apoptotic gene signature.

Although extensive studies have demonstrated the functional impairment of antigen-specific CD4(+) and CD8(+) T-cells during chronic hepatitis C virus (HCV) infection, the functional status of global CD4(+) and CD8(+) T-cells remains unclear. In this report, we recruited 42 long-term (~20 years) treatment-naïve chronic HCV (CHC) patients and 15 healthy donors (HDs) to investigate differences in global CD4(+) and CD8(+) T-cells function. We show that CD4(+) and CD8(+) T-cells from CHC patients underwent increased apoptosis after TCR stimulation. Furthermore, IFN-γ, IL-9 and IP-10 were elevated in CHC patients' plasma and promoted activation-induced T-cells death. Global CD4(+) and CD8(+) T-cells also showed unique transcriptional profiles in the expression of apoptosis-related genes. We identified BCL2, PMAIP1, and CASP1 in CD4(+) T-cells and IER3 and BCL2A1 in CD8(+) T-cells from CHC patients as HCV-specific gene signatures. Importantly, the gene expression patterns of CD4(+) and CD8(+) T-cells from CHC patients differ from those in CD4(+) and CD8(+) T-cells from human immunodeficiency virus type 1 (HIV-1) or hepatitis B virus (HBV) infected individuals. Our results indicate that chronic HCV infection causes a systemic change in cytokine levels that primes T-cells for activation-induced apoptosis. Furthermore, HCV infection programs unique apoptosis-related gene expression profiles in CD4(+) and CD8(+) T-cells, leading to their enhanced activation-induced apoptosis. These results provide novel insights to the pathogenesis of chronic HCV infection.

Structure-based high-throughput epitope analysis of hexon proteins in B and C species human adenoviruses (HAdVs).

Human adenoviruses (HAdVs) are the etiologic agent of many human infectious diseases. The existence of at least 54 different serotypes of HAdVs has resulted in difficulties in clinical diagnosis. Acute respiratory tract disease (ARD) caused by some serotypes from B and C species is particularly serious. Hexon, the main coat protein of HAdV, contains the major serotype-specific B cell epitopes; however, few studies have addressed epitope mapping in most HAdV serotypes. In this study, we utilized a novel and rapid method for the modeling of homologous proteins based on the phylogenetic tree of protein families and built three-dimensional (3D) models of hexon proteins in B and C species HAdVs. Based on refined hexon structures, we used reverse evolutionary trace (RET) bioinformatics analysis combined with a specially designed hexon epitope screening algorithm to achieve high-throughput epitope mapping of all 13 hexon proteins in B and C species HAdVs. This study has demonstrated that all of the epitopes from the 13 hexon proteins are located in the proteins' tower regions; however, the exact number, location, and size of the epitopes differ among the HAdV serotypes.

Downregulation of the AU-rich RNA-binding protein ZFP36 in chronic HBV patients: implications for anti-inflammatory therapy.

Inflammation caused by chronic hepatitis B virus (HBV) infection is associated with the development of cirrhosis and hepatocellular carcinoma; however, the mechanisms by which HBV infection induces inflammation and inflammatory cytokine production remain largely unknown. We analyzed the gene expression patterns of lymphocytes from chronic HBV-infected patients and found that the expression of ZFP36, an AU-rich element (ARE)-binding protein, was dramatically reduced in CD4(+) and CD8(+) T lymphocytes from chronic HBV patients. ZFP36 expression was also reduced in CD14(+) monocytes and in total PBMCs from chronic HBV patients. To investigate the functional consequences of reduced ZFP36 expression, we knocked down ZFP36 in PBMCs from healthy donors using siRNA. siRNA-mediated silencing of ZFP36 resulted in dramatically increased expression of multiple inflammatory cytokines, most of which were also increased in the plasma of chronic HBV patients. Furthermore, we found that IL-8 and RANTES induced ZFP36 downregulation, and this effect was mediated through protein kinase C. Importantly, we found that HBsAg stimulated PBMCs to express IL-8 and RANTES, resulting in decreased ZFP36 expression. Our results suggest that an inflammatory feedback loop involving HBsAg, ZFP36, and inflammatory cytokines may play a critical role in the pathogenesis of chronic HBV and further indicate that ZFP36 may be an important target for anti-inflammatory therapy during chronic HBV infection.

[Construction of platform on the three-dimensional finite element model of the dentulous mandibular body of a normal person].

OBJECTIVE: To develop a method to construct a three-dimensional finite element model of the dentulous mandibular body of a normal person. METHODS: A series of pictures with the interval of 0.1 mm were taken by CT scanning. After extracting the coordinates of key points of some pictures by the procedure, we used a C program to process the useful data, and constructed a platform of the three-dimensional finite element model of the dentulous mandibular body with the Ansys software for finite element analysis. RESULTS: The experimental results showed that the platform of the three-dimensional finite element model of the dentulous mandibular body was more accurate and applicable. The exact three-dimensional shape of model was well constructed, and each part of this model, such as one single tooth, can be deleted, which can be used to emulate various tooth-loss clinical cases. CONCLUSION: The three-dimensional finite element model is constructed with life-like shapes of dental cusps. Each part of this model can be easily removed. In conclusion, this experiment provides a good platform of biomechanical analysis on various tooth-loss clinical cases.