Zhengwen Liu

Prognostic role of neutrophil-to-lymphocyte ratio in colorectal cancer: a systematic review and meta-analysis.

The prognostic role of inflammation index like neutrophil‐to‐lymphocyte ratio (NLR) in colorectal cancer (CRC) remains controversial. We conduct a meta‐analysis to determine the predictable value of NLR in the clinical outcome of CRC patients. The analysis was carried out based on the data from 16 studies (19 cohorts) to evaluate the association between NLR and overall survival (OS) and progression‐free survival (PFS) in patients with CRC. In addition, the relationship between NLR and clinicopathological parameters was assessed. Hazard ratio (HR) or odds ratio (OR) with its 95% confidence interval (CI) was used as the effect size estimate. Our analysis results indicated that elevated pretreatment NLR predicted poorer OS (HR: 1.813, 95% CI: 1.499–2.193) and PFS (HR: 2.102, 95% CI: 1.554–2.843) in patients with CRC. Increased NLR is also significantly associated with the poorer differentiation of the tumor (OR: 1.574, 95% CI: 1.226–2.022) and higher carcino‐embryonie antigen (CEA) level (OR: 1.493, 95% CI: 1.308–1.705). By these results, we conclude that NLR gains a prognostic value for patients with CRC. NLR should be monitored in CRC patients for rational stratification of the patients and adjusting the treatment strategy.

Characterization of the Gene Expression Profile of Human Bocavirus

We have generated a quantitative transcription profile of human bocavirus type 1 (HBoV1) by transfecting a nearly full-length clone in human lung epithelial A549 cells as well as in a replication competent system in 293 cells. The overall transcription profile of HBoV1 is similar to that of two other members of genus Bocavirus, minute virus of canines and bovine parvovirus 1. In particular, a spliced NS1-transcript that was not recognized previously expressed the large non-structural protein NS1 at approximately 100kDa; and the NP1-encoding transcripts were expressed abundantly. In addition, the protein expression profile of human bocavirus type 2 (HBoV2) was examined in parallel by transfection of a nearly full-length clone in A549 cells, which is similar to that of HBoV1. Moreover, our results showed that, unlike human parvovirus B19 infection, expression of the HBoV1 proteins only does not induce cell cycle arrest and apoptosis of A549 cells.

Parvovirus B19 Infection of Human Primary Erythroid Progenitor Cells Triggers ATR-Chk1 Signaling, Which Promotes B19 Virus Replication

ABSTRACT Human parvovirus B19 (B19V) infection is restricted to erythroid progenitor cells of the human bone marrow. Although the mechanism by which the B19V genome replicates in these cells has not been studied in great detail, accumulating evidence has implicated involvement of the cellular DNA damage machinery in this process. Here, we report that, in ex vivo-expanded human erythroid progenitor cells, B19V infection induces a broad range of DNA damage responses by triggering phosphorylation of all the upstream kinases of each of three repair pathways: ATM (ataxia-telangiectasi mutated), ATR (ATM and Rad3 related), and DNA-PKcs (DNA-dependent protein kinase catalytic subunit). We found that phosphorylated ATM, ATR, and DNA-PKcs, and also their downstream substrates and components (Chk2, Chk1, and Ku70/Ku80 complex, respectively), localized within the B19V replication center. Notably, inhibition of kinase phosphorylation (through treatment with either kinase-specific inhibitors or kinase-specific shRNAs) revealed requirements for signaling of ATR and DNA-PKcs, but not ATM, in virus replication. Inhibition of the ATR substrate Chk1 led to similar levels of decreased virus replication, indicating that signaling via the ATR-Chk1 pathway is critical to B19V replication. Notably, the cell cycle arrest characteristic of B19V infection was not rescued by interference with the activity of any of the three repair pathway kinases.

Statin therapy improves response to interferon alfa and ribavirin in chronic hepatitis C: A systematic review and meta-analysis

The treatment of interferon alfa (IFN-α) and ribavirin for chronic hepatitis C virus (HCV) infection achieves limited sustained virological response (SVR). We conducted a systematic review and meta-analysis to explore the efficacy of adding statins to IFN-α and ribavirin therapy for chronic hepatitis C. Studies with data pertinent to the effect of statins on chronic hepatitis C were reviewed, and randomized controlled trials (RCTs) evaluating the efficacy of the addition of statins to IFN-α and ribavirin were included in meta-analysis. The primary outcome measure was SVR. Secondary outcome measures were rapid virological response (RVR) and early virological response (EVR). The literature was systematically searched through October 2012. After screening of the 1724 non-duplicated entries, 54 potentially relevant studies were fully reviewed. Of those, 18 studies were relevant and 5 RCTs met the inclusion criteria for meta-analysis. In comparison with IFN-α and ribavirin therapy, the addition of statins significantly increased SVR (OR=2.02, 95% CI: 1.38-2.94), RVR (OR=3.51, 95% CI: 1.08-11.42) and EVR (OR=1.89, 95% CI: 1.20-2.98). The SVR increase remained significant for HCV genotype 1 (OR=2.11, 95% CI: 1.40-3.18). There were no significant increases in adverse events and withdrawals with the addition of statins. In conclusion, the addition of statins to IFN-α and ribavirin improves SVR, RVR, and EVR without additional adverse events and thus may be considered as adjuvant to IFN-α and ribavirin for chronic hepatitis C. Statins might also be used for HCV genotypes other than genotype 1, or in patients in whom the use of protease inhibitors is contraindicated or not indicated.

Role of erythropoietin receptor signaling in parvovirus B19 replication in human erythroid progenitor cells.

ABSTRACT Parvovirus B19 (B19V) infection is highly restricted to human erythroid progenitor cells. Although previous studies have led to the theory that the basis of this tropism is receptor expression, this has been questioned by more recent observation. In the study reported here, we have investigated the basis of this tropism, and a potential role of erythropoietin (Epo) signaling, in erythroid progenitor cells (EPCs) expanded ex vivo from CD34+ hematopoietic cells in the absence of Epo (CD36+/Epo− EPCs). We show, first, that CD36+/Epo− EPCs do not support B19V replication, in spite of B19V entry, but Epo exposure either prior to infection or after virus entry enabled active B19V replication. Second, when Janus kinase 2 (Jak2) phosphorylation was inhibited using the inhibitor AG490, phosphorylation of the Epo receptor (EpoR) was also inhibited, and B19V replication in ex vivo-expanded erythroid progenitor cells exposed to Epo (CD36+/Epo+ EPCs) was abolished. Third, expression of constitutively active EpoR in CD36+/Epo− EPCs led to efficient B19V replication. Finally, B19V replication in CD36+/Epo+ EPCs required Epo, and the replication response was dose dependent. Our findings demonstrate that EpoR signaling is absolutely required for B19V replication in ex vivo-expanded erythroid progenitor cells after initial virus entry and at least partly accounts for the remarkable tropism of B19V infection for human erythroid progenitors.

IL17A gene polymorphisms, serum IL-17A and IgE levels, and hepatocellular carcinoma risk in patients with chronic hepatitis B virus infection

Interleukin (IL)‐17A plays important roles in hepatitis B virus (HBV)‐induced liver diseases. This study aims to investigate IL17A single nucleotide polymorphisms (SNPs) and the predispositions to chronic HBV infection and hepatocellular carcinoma (HCC) risk and the correlations to IL‐17A and IgE levels. Three hundred ninety‐five chronic HBV patients, 75 HBV infection resolvers, and 174 healthy controls were included. IL17A SNPs rs8193036 (C/T) and rs2275913 (A/G) and serum IL‐17A and IgE levels were determined. HBV infection resolvers had higher rs8193036 allele T and allele T‐containing genotypes than HBV patients or controls. Compared with chronic hepatitis, HCC patients had more frequent rs2275913 genotype GG (odds ratios [OR] 3.317, 95% confidence interval [CI] 1.663–6.617, P = 0.001) and allele G (OR 1.844, 95% CI 1.311–2.595, P < 0.001), and more frequent haplotypes CG (OR 1.868, 95% CI 1.256–2.778, P = 0.002) and TG (OR 1.788, 95% CI 1.031–3.101, P = 0.037) of rs8193036 and rs2275913. Comparison of HCC patients with cirrhosis yielded similar findings. Apart from male gender and older ages, IL‐17A level (OR 1.020, 95% CI 1.003–1.036, P = 0.019) and rs2275913 genotypes AG and GG (OR 1.704, 95% CI 1.214–2.390, P = 0.006) were factors significantly associated with HCC risk in multivariate analysis in comparison with HBV patients without HCC. These factors remained significant in multivariate analysis in relation to cirrhosis. IL17A rs2275913 genotype GG was associated with significantly increased IL‐17A and IgE levels. IL17A polymorphisms may influence HCC risk in chronic HBV infection via regulating IL‐17A production.

Xanthohumol, a main prenylated chalcone from hops, reduces liver damage and modulates oxidative reaction and apoptosis in hepatitis C virus infected Tupaia belangeri

Hepatitis C virus (HCV) infection in Tupaia belangeri (Tupaia) represents an important model of HCV infection. Xanthohumol (XN), a major prenylated chalcone from hops, has various biological activities including hepatopreventive and anti-viral activities. In this study, Tupaias infected with HCV RNA positive serum were used to evaluate the effects of XN on liver damage, oxidative reaction, apoptosis and viral protein expression in liver tissues. The Tupaias inoculated with HCV positive serum had elevated serum aminotransferase levels and inflammation, especially hepatic steatosis, and HCV core protein expression in liver tissue. In the animals inoculated with HCV positive serum, XN significantly decreased aminotransferase levels, histological activity index, hepatic steatosis score and transforming growth factor β1 expression in liver tissue compared with the animals without XN intervention. XN reduced HCV core protein expression in liver tissue compared with those without XN intervention but the difference was not significant. XN significantly decreased malondialdehyde, potentiated superoxide dismutase and glutathione peroxidase, reduced Bax expression, promoted Bcl-xL and inhibited caspase 3 activity in liver tissues compared with the animals without XN intervention. These results indicate that XN may effectively improve hepatic inflammation, steatosis and fibrosis induced by HCV in Tupaias primarily through inhibition of oxidative reaction and regulation of apoptosis and possible suppression of hepatic stellate cell activation. The anti-HCV potential of XN needs further investigation.

Association of polymorphisms of programmed cell death–1 gene with chronic hepatitis B virus infection

Programmed cell death-1 (PD-1) plays a critical role in regulating T-cell function during hepatitis B virus (HBV) infection. The present study investigated the relationships between the polymorphisms of the PD-1 gene and the susceptibility to chronic HBV infection. Single nucleotide polymorphisms (SNPs) in PD-1 gene at positions -606G/A (PD-1.1) and +8669 G/A (PD-1.6) were analyzed by bidirectional PCR amplification of specific alleles (Bi-PASA) in 198 chronic HBV patients and 280 controls. Although the genotype and allele frequencies of PD-1.1 were not different between chronic HBV patients and controls, the genotype and allele frequencies of PD-1.6 were significantly different. PD-1.6 GG genotype and the combination of genotypes with G allele were less frequent in HBV patients than in controls (p = 0.007 and p = 0.031, respectively). The allele G was also less frequent in patients than in controls (p = 0.006). Haplotype PD-1.1G/PD-1.6G was less frequent in patients than in controls (p = 0.001). Cirrhosis patients had a lower frequency of PD-1.6 G allele compared with controls (p = 0.007). Our findings, firstly reporting the association between PD-1 polymorphism and HBV infection, suggest that PD-1 gene may be one of the genes predisposing to chronic HBV infection and disease progression.

Comparison of the Transcription Profile of Simian Parvovirus with That of the Human Erythrovirus B19 Reveals a Number of Unique Features

ABSTRACT Simian parvovirus (SPV) is a member of the genus Erythrovirus and is closely related to the human parvovirus B19. Natural and experimental infection of monkeys with SPV resembles B19 infection of human. We report a detailed characterization of the viral RNAs and proteins generated following transfection of cloned SPV into COS cells and SPV infection of the human erythroid progenitor line UT-7/Epo-S1. SPV and B19 are 50% identical at the nucleotide level, and although their basic transcription and protein expression profiles were generally similar, there were also significant differences. SPV pre-mRNAs contain three introns, compared to two found for B19: an additional intron was found within the capsid-coding region. RNAs in which this intron was spliced were abundant and encoded the SPV 14-kDa protein (analogous to the B19 11-kDa protein), which initiated at an AUG in the exon preceding the third intron. Unlike B19, SPV RNAs were also spliced between the donor of the first intron and the acceptor of the second intron. The third intron was additionally spliced from a portion of these molecules; these mRNAs encoded the 14-kDa protein. A portion was not spliced further and encoded VP2. Like B19, SPV has a polyadenylation signal [AAUAAA (pA)p] in the middle of the genome, which directed efficient polyadenylation of both spliced and unspliced mRNAs (encoding a putative 10-kDa protein, analogous to the B19 7.5-kDa protein, and SPV NS1, respectively). The 14-kDa protein was localized to both in the nucleus and cytoplasm.

Human Parvovirus B19 DNA Replication Induces a DNA Damage Response That Is Dispensable for Cell Cycle Arrest at Phase G2/M

ABSTRACT Human parvovirus B19 (B19V) infection is highly restricted to human erythroid progenitor cells, in which it induces a DNA damage response (DDR). The DDR signaling is mainly mediated by the ATR (ataxia telangiectasia-mutated and Rad3-related) pathway, which promotes replication of the viral genome; however, the exact mechanisms employed by B19V to take advantage of the DDR for virus replication remain unclear. In this study, we focused on the initiators of the DDR and the role of the DDR in cell cycle arrest during B19V infection. We examined the role of individual viral proteins, which were delivered by lentiviruses, in triggering a DDR in ex vivo-expanded primary human erythroid progenitor cells and the role of DNA replication of the B19V double-stranded DNA (dsDNA) genome in a human megakaryoblastoid cell line, UT7/Epo-S1 (S1). All the cells were cultured under hypoxic conditions. The results showed that none of the viral proteins induced phosphorylation of H2AX or replication protein A32 (RPA32), both hallmarks of a DDR. However, replication of the B19V dsDNA genome was capable of inducing the DDR. Moreover, the DDR per se did not arrest the cell cycle at the G2/M phase in cells with replicating B19V dsDNA genomes. Instead, the B19V nonstructural 1 (NS1) protein was the key factor in disrupting the cell cycle via a putative transactivation domain operating through a p53-independent pathway. Taken together, the results suggest that the replication of the B19V genome is largely responsible for triggering a DDR, which does not perturb cell cycle progression at G2/M significantly, during B19V infection.