Guang Wen Cao

Factors predicting occurrence and prognosis of hepatitis-B-virus-related hepatocellular carcinoma

Primary liver cancer is an important cause of cancer death, and hepatocellular carcinoma (HCC) accounts for 70%-85% of total liver cancer worldwide. Chronic hepatitis B virus (HBV) infection contributes to > 75% of HCC cases. High serum viral load is the most reliable indicator of viral replication in predicting development of HCC. HBV genotype C is closely associated with HCC in cirrhotic patients aged > 50 years, whereas genotype B is associated with development of HCC in non-cirrhotic young patients and postoperative relapse of HCC. Different HBV subgenotypes have distinct patterns of mutations, which are clearly associated with increased risk of HCC. Mutations accumulate during chronic HBV infection and predict occurrence of HCC. Chronic inflammation leads to increased frequency of viral mutation via cellular cytidine deaminase induction. Mutations are negatively selected by host immunity, whereas some immuno-escaped HBV mutants are active in hepatocarcinogenesis. Inflammatory pathways contribute to the inflammation-necrosis-regeneration process, ultimately HCC. Their hallmark molecules can predict malignancy in HBV-infected subjects. Continuing inflammation is involved in hepatocarcinogenesis and closely related to recurrence and metastasis. HBV load, genotype C, viral mutations and expression of inflammatory molecules in HBV-related HCC tissues are significantly associated with poor prognosis. Imbalance between intratumoral CD8(+) T cells and regulatory T cells or Th1 and Th2 cytokines in peritumoral tissues can predict prognosis of HBV-related HCC. These factors are important for developing active prevention and surveillance of HBV-infected subjects who are more likely to develop HCC, or for tailoring suitable treatment to improve survival or postpone postoperative recurrence of HCC.

Environmental and Psycho-social Factors Related to Prostate Cancer Risk in the Chinese Population： a Case-control Study

OBJECTIVEnTo study the risk environmental and psycho-social factors associated to prostate cancer (PCa) in Chinese population.nnnMETHODSn250 PCa patients and 500 controls were enrolled in this case-control study. Information was collected and logistic regression analysis was used to estimate the odds ratios (OR) and 95% confidence intervals (95% CI) for relationship between lifestyle, eating habits and psycho-social factors with PCa risk.nnnRESULTSnGreen vegetables and green tea were associated with a decreased risk of PCa (OR=0.39, 95% CI: 0.28-0.53; OR=0.59, 95% CI: 0.40-0.87, respectively). Family history of PCa (OR=7.16, 95% CI: 2.01-25.49), history of prostate diseases (OR=2.28, 95% CI: 1.53-3.41), alcohol consumption (OR=1.97, 95% CI: 1.33-2.90), red meat consumption (OR=1.74, 95% CI: 1.20-2.52), barbecued (OR=2.29, 95% CI: 1.11-4.73) or fried (OR=2.35, 95% CI: 1.24-4.43) foods were related with increased PCa risk. Negative psycho-social factors including occupational setbacks (OR=1.61, 95% CI: 1.00-2.59), marital separation (OR=1.94, 95% CI: 1.29-2.91), self-contained suffering (OR=2.37, 95% CI: 1.58-3.55), and high sensitivity to the personal comments (OR=1.73, 95% CI: 1.18-2.54) were related to PCa.nnnCONCLUSIONnRegular consumption of green vegetables and green tea may suggest protective effects on PCa. Alcohol consumption, red meat consumption and barbecued or fried foods were associated with PCa. Negative psycho-social factors may also play a role in the incidence of PCa in Chinese population.

Genetic variation in the GSTM3 promoter confer risk and prognosis of renal cell carcinoma by reducing gene expression.

Background:Glutathione S-transferase mu 3 (GSTM3) has been proven to be downregulated in renal cell carcinoma (RCC). We aimed to characterise the role of GSTM3 and its genetic predisposition on the occurrence and postoperative prognosis of RCC.Methods:The effect of GSTM3 on RCC aggressiveness was examined using transfection and silencing methods. Glutathione S-transferase mu 3 expression in renal tissues was examined by immunohistochemistry. The associations of rs1332018 (A-63C) and rs7483 (V224I) polymorphisms with RCC risk were examined using 400 RCC patients and 802 healthy controls. The factors contributing to postoperative disease-specific survival of RCC patients were evaluated using the Cox proportional hazard model.Results:Glutathione S-transferase mu 3 silencing increased the invasion and anchorage-independent growth of RCC cell lines. rs1332018 (AC+CC vs AA), which correlated with low expression of GSTM3 in kidney, was associated with RCC risk (odds ratio, 1.446; 95% confidence interval (CI), 1.111–1.882). rs1332018 variants and low GSTM3 expression significantly predicted unfavourable postoperative survivals of RCC patients (P<0.05). rs1332018 variants independently predicted a poor prognosis (hazard ratio, 2.119; 95% CI, 1.043–4.307).Conclusion:Glutathione S-transferase mu 3 may function as a tumour suppressor in RCC. rs1332018 genetic variants predispose the host to downregulating GSTM3 expression in kidney, facilitate carcinogenesis, and predict an unfavourable postoperative prognosis of RCC.

Association of novel mutations and heplotypes in the preS region of hepatitis B virus with hepatocellular carcinoma

The association of viral mutations and haplotypic carriages with mutations in the preS region of hepatitis B virus (HBV) genotypes B and C with hepatocellular carcinoma (HCC) is of great significance for the prediction of this malignancy, but it remains obscure. We analyzed the preS sequences of HBV genotypes B and C from 1172 HBV-infected subjects including 231 patients with HCC. As compared with the HBV-infected subjects without HCC, C2875T, G2946C, A3054C, C3060A, T3066C, C3116T, A3120C, G3191A, A1C, C7A, C10A, A31C, C76T, G105C, and G147C in both genotypes were significantly associated with increased risks of HCC. C2875A, G2950A, G2951A, A3054T, C3060T, T3066A, T3069G, A3120T, and G3191C were significantly associated with increased risks of HCC in genotype C, whereas these mutations were inversely associated with HCC in genotype B. Multivariate regression analyses showed that C76A/T was a novel factor independently associated with an increased risk of HCC, as compared with those without HCC. The frequencies of haplotypes 2964A-3116T-preS2 start codon wild-type-7C, 2964C-3116T-7A-76C, and 2964A-3116T-7C-76A/T were significantly higher in the patients with HCC (P<0.001), whereas a haplotypic carriage with a single mutation and another three wildtypes were inversely associated with HCC. Conclusively, the association of HBV mutations in the preS region with HCC depends on HBV genotype and haplotypic carriage with two or more mutations that are each associated with an increased risk of HCC independently.

Phylogenetic analysis of hemagglutinin (HA) gene of the novel avian influenza virus A/H7n9

Objective To investigate the evolution and variations in coding amino acids of hemagglutinin(HA) gene of the novel avian influenza virus H7N9 in 2013 epidemic.Methods The HA gene sequences of influenza virus H7N9,H7N2,H7N3 and H7N7 subtypes were downloaded from the database of The National Center for Biotechnology Information(NCBI) and The Global Initiative on Sharing All Influenza Data(GISAID).MEGA 5.05 software was used for sequence analysis and N-J method was used for constructing the phylogenetic trees.The amino acid sequences at the receptor binding sites,glycosylation sites,and cleavage sites was aligned and analyzed.Results The HA genes this novel A/H7N9 virus in 2013 shared a 95.3%-95.6% similarity with JQ906573.1|Zhejiang(H7N3 virus) isolated in 2011.The most important variation in this novel H7N9 isolates was found at the receptor binding site: Q226L.The 5 glycosylation sites were highly conservative.One basic amino acid(R) at the HA cleavage sites,located between aa339 and aa340,was also found in this novel isolate.Conclusion The HA gene of this novel H7N9 isolate might originate from H7 subtypes carried by birds in China.The binding site change caused by Q226L variation might be responsible for human infection of this novel H7N9 isolate.

Evolution analysis of hemagglutinin gene of novel influenza virus A/H1N1 in 2009 pandemic.

Objective:To investigate the evolutionary relationship of the hemagglutinin(HA)gene of novel influenza virus A/H1N1 in 2009 pandemic with the HA genes of A/H1N1 viruses isolated in different parts of the world previously.Methods:The sequences of the HA gene of the novel A/H1N1 strain and the reference sequences of human,swine,and avian influenza A viruses were retrieved from NCBI.MEGA 4.0 software was employed to align,blunt nucleotide sequences,and construct phylogenetic tree.The deduced amino acid sequences of the HA genes of novel influenza virus A/H1N1 were compared with those of the A/H1N1 isolates in North America,Europe,and Asia.Results:Phylogenetic tree of the HA genes of A/H1N1 strains worldwide showed that the HA genes of novel influenza virus A/H1N1 in 2009 shared a high homology with those of the 7 human A/H1N1 influenza viruses isolated in North America during 1976 to 2007,and shared a low homology with those of the human influenza viruses A/H1N1 isolated in Europe and Asia.Phylogenetic tree of the HA gene between different species showed that the HA genes of novel influenza virus A/H1N1 in 2009 had a close evolutionary relationship with those of the two swine A/H1N1 strains isolated in 1998 and 2007 in North America,but a distant evolutionary relationship with those of swine and avian A/H1N1 isolated in Europe and Asia.Alignment of amino acid at important antigenic sites showed that the HA gene of the novel A/H1N1 strains shared important antigen sites with the swine A/H1N1 influenza viruses isolated in North America,and did not share with the swine A/H1N1 influenza viruses isolated in Europe and Asia or the human A/H1N1 influenza vaccine strains.Conclusion:The HA genes of the novel influenza virus A/H1N1 might originate from swine A/H1N1 influenza viruses in North America after a long time evolution and the reassortment with fragments of human A/H1N1 in the area,and the current A/human/H1N1 influenza vaccine may not be effective for the novel A/H1N1 virus.

Evolutionary characteristics of polymerase PA,PB1,and PB2 genes of novel influenza virus A/H1N1 in 2009 pandemic

Objective:To elucidate the evolutionary characteristics of polymerase PA,PB1,and PB2 genes of the novel influenza virus A/H1N1 in 2009 pandemic.Methods:The sequences of the PA,PB1,and PB2 genes of the novel H1N1 strains in 2009 pandemic,and the reference sequences of human,swine,and avian influenza viruses isolated during different years at different locations were retrieved from NCBI.Molecular Evolutionary Genetics Analysis version 4.0(MEGA4.0)software was employed to align and blunt nucleotide sequences,construct phylogenetic tree,deduce and align PB2 protein sequences,and the results were compared between the novel A/H1N1 and each of the reference strains.Results:The sequences of the PA,PB1,and PB2 genes of 2009 novel A/H1N1 strains isolated from different locations shared a high homology and clustered in a unique new clade,and were close to the swine influenza viruses.The PA,PB1,and PB2 genes of the novel H1N1 viruses had a high similarity with the corresponding sequences of a human H1N1 strain isolated in Iowa State of USA in 2005(A/Iowa/CEID23/2005/H1N1).Alignments of the deduced protein sequences showed that the 627th amino acid of PB2 of the novel H1N1 strains and A/Iowa/CEID23/2005/H1N1 were glutamic acid(Glu),which was the same as that in the avian influenza virus in Iowa State of USA in 2005(DQ889682),and was different from those of the reference sequences of human A/H1N1 strains isolated from 1918 to 2008,which were lysine(Lys).Conclusion:The 2009 novel A/H1N1 virus might be originated from the human A/H1N1 strains isolated in 2005 in Iowa State of America(A/Iowa/CEID23/2005/H1N1),and the polymerase gene of the novel H1N1 virus might re-assort with avian A influenza virus.

Recombination analysis of full-length genomic sequences of novel influenza virus A/H1N1 in 2009 pandemic

Objective:To analyze the recombination of full-length genomic sequences of novel influenza virus A/H1N1 in 2009 pandemic.Methods:The full-length sequences of the novel A/H1N1 and reference sequences were downloaded from NCBI database.MEGA4.0 software was used to connect,align sequences,and analyze the similarity between the full-length sequences of the novel virus and each of the reference strains.Recombination was analyzed by Simplot software(version 3.5.1).Results:Simplot analysis indicated that the PB1 genes(polymerase B1,PB1)of the novel A/H1N1 viruses might evolve from human H3N2 virus(identity:93.7%);the PB2 genes(polymerase B2,PB2)and the PA genes(polymerase A,PA)might evolve from avian H5N1 viruses(identity:89.0%,89.9%,respectively);the HA genes(hemagglutinin,HA),the NP genes(nucleoprotein,NP)and the NS genes(non-structural protein,NS)showed high similarities with those of swine H1N1 viruses isolated in North America(identity:91.7%,93.1%,and 93.1%,respectively);and the NA genes(neuraminidase,NA)and the MP genes(matrix protein,MP)might evolve from European swine H1N1 viruses(identity:90.5%,95.5%,respectively).The full-length sequence of the novel A/H1N1 viruses had a highest similarities with swine H1N1 viruses isolated in North America(identity:83.9%).Conclusion:The novel influenza virus A/H1N1 is a recombinant virus evolving from human H3N2 viruses,swine H1N1 from North America,swine H1N1 from Europe,and swine H5N1 from Asia.

Molecular evolutionary analysis of matrix protein and nucleoprotein genes of novel influenza virus A/H1N1 in 2009 pandemic.

Objective:To analyze evolutionary characteristics of the matrix protein(M)and nucleoprotein(NP)genes of influenza virus A/H1N1 in 2009 pandemic.Methods:The M and NP genes of A/H1N1 viruses were downloaded from NCBI database.MEGA4.0 software and NJ method were used for sequence alignment,protein sequence alignment,and the phylogenetic tree construction.Meanwhile,Epi Info software was used to analyze the linear trend of evolutionary distance of the M and NP genes of human H1N1 strains isolated during 1918 to 2009.Results:The M and NP gene sequences were similar among the novel A/H1N1 viruses,but different from those of the previous influenza H1N1 viruses.Using reference sequences of human H1N1 strains isolated during 1918 to 2008,we found that changes in evolutionary distances of the M genes between novel A/H1N1 strains and each of the reference A/H1N1 strains increased with increasing year intervals(Ptrend = 0.001).Compared with the amino acid sequence of M2 protein of reference human A/H1N1 virus strains isolated during 1918 to 2008,the novel A/H1N1 viruses had the amino acid substitutions at 6 sites:11,43,54,57,77,and 78.Compared with swine and avian A/H1N1,the novel A/H1N1 virus only had the amino acid substitutions at 43 and 77.Conclusion:The NP gene of novel A/H1N1 virus,which is routinely considered as a conserved sequence,is different from those of the previously isolated human H1N1 influenza viruses;the related mechanisms and consequences on viral activity remain to be elucidated.The substitution to threonine at 11 and 43 amino acids of M2 protein might contribute to amantadine resistance of the novel H1N1 virus pandemic in 2009.

Role of HBV subgenotype C2, B2 in carcinogenesis, treatment and prognosis of hepatocellular carcinoma

Objective:To investigate the role of HBV subgenotypes B2,C2 in the carcinogenesis,treatment and prognosis of hepatocellular carcinoma(HCC).Methods:HBV genotypes and subgenotypes were detected in 462 HCC patients and 234 chronic hepatitis B(CHB)patients by a multiplex PCR assay,and HCC patients infected with HBV B2 or C2 were followed up for a year after surgical resection,transarterial chemoembolization(TACE)or a combination of both.Results:The HCC patients infected with HBV C2 had a higher chance to receive surgical treatment than those with B2(P=0.007).Age of 40 years or older(P=0.030),male gender(P=0.000),and viral load(10 000 copies/ml)(P=0.017)were the independent risk factors for the carcinoge-nesis of HCC by using multivariate logistic analysis;however,there was no significant difference in the carcinogenesis of HCC between CHB patients with HBV subgenotypes B2 and C2.Age of 50 years or younger(P=0.044),infection with HBV B2(P=0.027),and non-surgical treatment(P=0.000)were the independent risk factors for the recurrence of HCC.Thick trabecular type was more prevalent in HCC patients infected with HBV B2,C2 and genotype mixture(85.7%,71.2% and 75.0%,respectively),and the proportions of histopathological types were not significantly different between HCC patients infected with HBV B2,C2 and genotype mixture.HBV subgenotype C2 was found in all HCC patients with rare histopathological type and subgenotype B2 and mixture were no found.Conclusion:There is no significant difference in the carcinogenesis of HCC between CHB patients with HBV subgenotypes B2 and C2.The HCC patients infected with HBV B2 have a lower chance to receive surgical treatment and are more severe than those with C2.HBV B2 is also closely associated with recurrence of HCC.