The association between IGF1 gene rs1520220 polymorphism and cancer susceptibility: a meta-analysis based on 12,884 cases and 58,304 controls

BACKGROUND@#The rs1520220 polymorphism in the insulin-like growth factor 1 (IGF1) gene has been reported to affect cancer susceptibly in several studies. However, the results of the relevant studies are inconsistent. We conduct a current meta-analysis to investigate the association between rs1520220 and cancer susceptibly.@*METHODS@#Three databases (PubMed, Embase, and Web of Science) were searched for studies regarding the relationship between rs1520220 and cancer susceptibly. Odds ratios (ORs) and the related 95% confidence intervals (CIs) were employed to assess the strength of the associations. A stratified analysis was performed according to cancer type, ethnicity, and quality score, and when results were obtained from no fewer than two studies, these results were pooled.@*RESULTS@#There was no positive association between rs1520220 and overall cancer risk. However, the analysis stratified by ethnicity revealed that rs1520220 significantly increased cancer susceptibility in Asian populations (allele model OR = 1.10, 95%Cl = 1.00-1.21, p = 0.040; homozygote model OR = 1.22, 95%Cl = 1.01-1.47, p = 0.040; dominant model OR = 1.19, 95%Cl = 1.01-1.39, p = 0.033). No significantly association was detected in Caucasian populations. The analysis stratified by cancer type suggested that rs1520220 was not associated with susceptibility to breast cancer.@*CONCLUSIONS@#The results of our meta-analysis demonstrate that the role of IGF1 rs1520220 in cancer susceptibility varies by ethnicity and cancer type and that rs1520220 increases cancer susceptibility in Asian populations.

Correlative analysis of different HBV genotypes and autoantibodies in hepatitis B patients / 中华肝脏病杂志

To study the genotypes of hepatitis B virus (HBV) in patients from Chongqing district and determine the prevalence of autoantibodies in these patients. HBV genotyping was carried out by restriction fragment length polymorphism analysis of venous blood serum samples from 252 chronic hepatitis B (CHB) patients and 25 healthy controls. Indirect immunofluorescent assay was used to detect autoantibodies, including antinuclear antibody, anti-mitochondrial antibody, anti-smooth muscle (SM) antibody, and anti-liver and kidney microsomal antibody. Immunospot assay was used to detect anti-ribonucleoprotein/anti-SM antibodies, anti-SS-A antibody, anti-SS-B antibody, anti-scl-70 antibody, and anti-Jo-1 antibody. Correlations between the production of autoantibodies and patient age and sex and various genetypes of HBV were analyzed by the Chi-squared test. The most frequent HBV genotype in CHB patients was B (67.3%), followed by genotype C (32.7%). Genotypes A, D, E, F, G and H were not detected in any of the CHB patients. The positive rate of autoantibodies was higher in the CHB patients than in the healthy group (76.98% vs. 12.00%, X2 = 44.60, P less than 0.05). There was no significant differences in the autoantibodies profiles of CHB patients carrying the B or C genotypes ( X2 = 0.0016, P more than 0.05). The main HBV genotypes in CHB patients in the Chongqing district are B and C. Autoantibodies are prevalent among these CHB patients, and are correlated with patient age and course of liver disease but not HBV genotype or patient sex.

P19 of Tomato Bushy Stunt Virus Suppresses RNA Silencing Induced by Short Hairpin RNA in Mammal Cells / 中国病毒学

To counteract the immune system in parasitic hosts, some viruses encode proteins to suppress the RNA interference (RNAi) effect. In this report, we established two RNAi systems to be easily observed with strong and obvious effect. The function of the P19 of tomato bushy stunt virus, which suppresses RNAi in mammal cells, was then studied using these two systems. Short hairpin RNAs targeting green fluorescence protein (pshRNA-GFP) and firefly luciferase (pshRNA-luc) were designed and inserted into a eukaryotic transcriptional vector pTZU6+1, respectively. The shRNA expressing vectors were co-transfected with plasmids containing the target gene with or without P19. The GFP expression level was assayed by fluorescence microscopy, Western blotting and RT-PCR. The luciferase expression level was analyzed by the dual-luciferase assay system. pshRNA designed in this study down-regulated the target gene specifically and efficiently, with a decrease of expression of both genes of about 70%, respectively. When P19 was introduced into the RNAi systems, the expression of both GFP and the luciferase were mostly recovered compared with the control groups. The RNAi systems of GFP and luciferase were constructed successfully, demonstrating that P19 of tomato bushy stunt virus has the ability to counteract the RNAi effect induced by shRNA in mammal cells.

The effect of HCV NS5A protein on HCV IRES-dependent translation in HepG2 cells / 中华肝脏病杂志

<p><b>OBJECTIVE</b>To study the effect of HCV NS5A protein on HCV IRES-dependent translation in HepG2 cells.</p><p><b>METHODS</b>HepG2 cells were co-transfected with a plasmid vector containing a bicistronic transcript carrying Renilla luciferase and firefly luciferase genes separated by HCV IRES sequences, and an expressing vector producing the NS5A protein. The luciferase activity and the mRNA of the luciferase gene were then detected. The NS5A expression was confirmed by fluorescence microscopy.</p><p><b>RESULTS</b>HCV NS5A protein was detected in the cytoplasm of the HepG2 cells transfected with pcDNA-NS5A, and the luciferase activity was up-regulated in the presence of the HCV NS5A protein while the expression of luciferase mRNA showed no difference.</p><p><b>CONCLUSION</b>HCV NS5A protein can upregulate the HCV IRES activity and this effect is dose-dependent with NS5A.</p>

Inhibition of HBV replication and antigen expression by RNA interference against different targets / 中华肝脏病杂志

<p><b>OBJECTIVES</b>To observe the inhibition of HBV replication and antigen expression by RNA interference aimed at different parts of the HBV genome.</p><p><b>METHODS</b>Following the rules of shRNA expression vector design and construction, we constructed seven kinds of sequence specific vectors and two kinds of mutant shRNA expression ones. We then cotransfected those shRNA and HBV expression vectors into HepG2 cells using lipofectamine2000. The level of HBV replication was investigated using Southern blot and the antigen expression using ELISA.</p><p><b>RESULTS</b>The replication of HBV DNA was inhibited by many shRNAs, especially the ones against P1, S2, C2, S1 and X. The inhibition rate against P1 was as high as 95%. Results obtained with ELISA showed that the shRNAs targeting C2, C1 and S2 had high rates of inhibition to HBsAg.</p><p><b>CONCLUSION</b>The replication and antigen expression of HBV could be inhibited by shRNAs aimed at four different open read frames, and higher inhibition rates of HBV replication and surface antigen expression could be obtained by P1 and C2, respectively.</p>

Inhibition of HCV IRES controlled reporter gene expression by RNA interference / 中华肝脏病杂志

<p><b>OBJECTIVE</b>To develop a RNAi approach that specifically targets the HCV IRES sequence by vector-expressed short hairpin RNA (shRNA) in vitro, and to assess the inhibitory effect of the shRNA on reporter gene expression.</p><p><b>METHODS</b>Eukaryotic expressing plasmids, pIRES-GFP and p5' UTR-Luc containing GFP or luciferase gene controlled by HCV IRES were cotransfected into HepG2 cells with either a RNAi plasmid pshRNA-HCV or a control plasmid pTZU6+1. At 24, 48, 72 hours post transfection, the fluorescence in the transfected cells was studied using fluorescence microscopy. The levels of GFP RNA were determined using RT-PCR and those of protein were determined using Western blot. The activities of luciferase were assayed using a dual luciferase assay system.</p><p><b>RESULTS</b>The introduction of RNAi plasmid efficiently and specifically down-regulated the expression of the reporter gene. RT-PCR showed that the RNAs of GFP gene were distinctly reduced (about 60%) when the pIRES-GFP was cotransfected with pshRNA-HCV, whereas the control vector did not exhibit inhibitory effect on the mRNA level, according to Western blot assay. The luciferase activity also decreased by 60%-70% in comparison to the control plasmid.</p><p><b>CONCLUSION</b>Our results demonstrate that the shRNA targeting HCV IRES shows a strong inhibitive effect on the expression of the reporter gene controlled by this sequence, suggesting that RNAi-based anti-HCV strategy may represent a potential approach in the therapy of HCV infection.</p>

A method of HPRE synthesis via transcription by T7 RNA polymerase in vitro / 中华肝脏病杂志

<p><b>OBJECTIVE</b>To synthesize highly pure HBV post-transcriptional regulatory element (HPRE) via transcription in vitro by T7 RNA polymerase.</p><p><b>METHODS</b>HPRE gene was amplified by PCR from a template containing HBV complete genomic DNA and cloned into plasmid pGEM-11zf. The cloned DNA sequence was transcribed by T7 RNA polymerase.</p><p><b>RESULTS</b>The construction of HPRE gene recombinant plasmid and production of HPRE via transcription in vitro was successful.</p><p><b>CONCLUSION</b>In vitro transcription by T7 RNA polymerase can be used to synthesize highly pure HPRE.</p>

The promoter activity of the DNA sequence corresponding to HCV 5'UTR in HepG2 / 中华肝脏病杂志

<p><b>OBJECTIVE</b>To study the promoter activity in HepG2 cells of the DNA sequence corresponding to the HCV 5'UTR.</p><p><b>METHODS</b>Plasmids, 5'UTR-Luc(+) and 5'UTR-Luc(-) carrying the forward and reverse DNA sequences corresponding to the HCV 5'UTR respectively were constructed, and subsequently transfected into HepaG2 cells. The luciferase activity and the mRNA of the luciferase gene were then detected. The 5'UTR sequence was cloned into a GFP vector to make 5'UTR-EGFP, and then the GFP expression was confirmed by fluorescence microscopy.</p><p><b>RESULTS</b>5'UTR-Luc(+) had an obvious luciferase activity whereas 5'UTR-Luc(-) had nearly no luciferase activity. The former had a high level of luciferase mRNA while the latter could not be detected. An intense green fluorescence expression was observed in the cells transfected with the plasmid of 5'UTR-EGFP.</p><p><b>CONCLUSION</b>The forward DNA sequence corresponding to HCV 5'-UTR had an obvious promoter activity in hepG2 cells. It may play an important role in the replication of HCV.</p>

Comparison of clinical course of patients with severe acute respiratory syndrome among the multiple generations of nosocomial transmission / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Severe acute respiratory syndrome (SARS) is characterized by both an atypical pneumonia and efficient nosocomial transmission. However, it remains unknown whether the infectivity and the virulence of the pathogen will change throughout the successive transmission. This study was conducted to compare the clinical features and management regimens of patients with SARS among the multiple generations from nosocomial transmission initiated by a super-spreader.</p><p><b>METHODS</b>The clinical data of 84 epidemiologically-linked SARS patients from a hospital outbreak were retrospectively studied. All patients, in whom a clear-cut transmission generation could be noted, had a direct or indirect exposure to the index patient and the epidemic successively propagated through the multiple generations of cases within a short period of time.</p><p><b>RESULTS</b>There were 66 women and 18 men with mean age of (29.2 +/- 10.3) years in this cluster; and 96.4% of whom were health care workers. Detailed contact tracing identified 35 (41.7%) first-generation cases, 34 (40.5%) second-generation cases, and 15 (17.8%) third-generation cases. No statistical differences among the multiple generations of transmission were found in terms of age, gender, incubation period and length of hospital stay. With the advanced transmission generations, the initial temperature lowered, the number of cases with dry cough decreased. There were no statistical differences in the peak temperature and duration of fever, other accompanying symptoms, leucopenia; however, the time from initial pulmonary infiltrates to radiographic recovery shortened (P < 0.05). No differences were found in maximum number of lung fields involved, duration from the onset of fever to the occurrence of pulmonary infiltrates and time from the initial pulmonary infiltrate to its peak among the multiple transmission generations (P > 0.05). No statistical differences were found in modes of oxygen therapy and sorts of antibiotics prescribed among the various transmission generations (P > 0.05); however, as with the advanced transmission generations, the number of cases prescribed with methylprednisolone, human gamma-globulin, interferon-alpha, antiviral drugs (oral ribavirin or oseltamivir) increased (P < 0.05) and time from admission to starting these medication shortened (P < 0.05).</p><p><b>CONCLUSIONS</b>There is no evidence that SARS infection will evolve or transmit within a fashion that permits it to become less powerful throughout the successive transmission within a short time.</p>