Evaluation of liver tissue by polymerase chain reaction for hepatitis B virus in patients with negative viremia

Association of Myxovirus Resistance Gene Promoter Polymorphism with Response to Combined Interferon Treatment and Progression of Liver Disease in Chronic HCV Egyptian Patients

To evaluate the frequency of single-nucleotide polymorphism at the -88 myxovirus resistance (MxA) gene promoter region in relation to the status of hepatitis C virus (HCV) progression and response to combined interferon (IFN) in chronic HCV Egyptian patients. One hundred ten subjects were enrolled in the study; 60 HCV genotype 4-infected patients who underwent combined IFN therapy and 50 healthy individuals. All subjects were genotyped for -88 MxA polymorphism by the restriction fragment length polymorphism technique. There was an increasing trend of response to combined IFN treatment as 34.9% of GG, 64.3% of GT, and 66.7% of TT genotypes were sustained responders (P=0.05). The T allele was significantly affecting the response rate more than G allele (P=0.032). Moreover, the hepatic fibrosis score and hepatitis activity were higher in GG genotypes compared with the GT and TT genotypes. The multivariate analysis showed that the MxA GG genotype was an independent factor increasing the no response to IFN therapy (P=0.04, odds ratio [OR] 3.822, 95% confidence interval [CI] 1.056-11.092), also MxA G allele (P=0.0372, OR 2.905, 95% CI 1.066-7.919). MxA -88 polymorphism might be a potential biomarker to predict response to IFN and disease progression in chronic HCV-infected patients.

Association between low molecular polypeptide 7 single nucleotide polymorphism and response to therapy in hepatitis C virus infection

AIM

To investigate the relationship between low molecular polypeptide-7 (LMP-7) gene polymorphism and response to interferon (IFN) therapy in chronic hepatitis C virus (HCV) patients.

METHODS

LMP-7 polymorphism at codon 49 with nucleotide substitution from A to C was amplified in 104 chronic HCV patients of genotype 4. The amplicons were digested with restriction endonuclease BsmI and the produced restriction fragment length polymorphism was analyzed. Patients received IFN + regional blood volume therapy for 48 wk and the frequency of this single nucleotide polymorphism (SNP) was statistically correlated with treatment response. The exclusion criteria for these patients were stated by the national health program for treating viral hepatitis. Main exclusion criteria included co-infection with hepatitis B virus or schistosomiasis, thyroid dysfunction, uncontrolled diabetes mellitus, history of long term drug or alcohol intake and autoimmune hepatitis. Multivariate analyses were done to correlate LMP-7 SNP plus several factors such as age, gender, weight, serum alpha-fetoprotein (AFP) and alanine aminotransferase levels, liver activity, fibrosis score and viral load with response to therapy.

RESULTS

The data presented in this study clearly demonstrated statistically significant differences between sustained virological response (SVR) (defined as the absence of HCV RNA levels in the patient's sera at least 6 mo after discontinuation of treatment) and non-response (NR) (where HCV RNA levels in the patient's sera never become undetectable for 6 mo during or after treatment). Variables were described as odds ratio with 95%CI. The data were considered significant if P values were ≤ 0.05; highly significant if P < 0.01 and very highly significant if P < 0.001. Current data showed that 91.7% of patients carrying LMP-7 C/C allele were associated with SVR, while the other two genotypes C/A and A/A were associated with NR patients, 83.3% and 64.3% respectively, showing that genotype CC was strongly associated with response to interferon (95%CI: 12.0719-134.6572, P = 0.0001). The majority of parameters recorded in SVR and NR patients included higher values of mean age (P = 0.004), alanine aminotransferase (P = 0.001), AFP (P = 0.001), body weight (P = 0.025), viral load (P = 0.025), higher fibrosis and histological activity index indices among NR vs SVR patients. Also, the multivariate statistical analysis of the different factors of fibrosis score, liver activity grade, genotypes and alleles of LMP-7 gene polymorphism in responders and NRs of HCV patients in this study showed that HCV patients with A allele had a very highly significant association with the NRs, high fibrosis and higher liver activity, while the C allele had a very highly significant association with the responders, low fibrosis and lower liver activity (95%CI: 3.5800-13.2519, P = 0.0001).

CONCLUSION

LMP-7 SNP is a candidate gene that should be considered when designing a mathematical model for predicting response to therapy and disease progression in HCV patients.

Detection of hepatitis B virus DNA in paraffin-embedded intrahepatic and extrahepatic cholangiocarcinoma tissue in the northern Chinese population

This study explored the importance of hepatitis B virus infection in cholangiocarcinoma pathogenesis in northern China. The clinical data of 66 patients with cholangiocarcinoma were analyzed. The hepatitis B virus gene was amplified using nested polymerase chain reaction, and the hepatitis B virus-related antigen was detected using immunohistochemistry in formalin-fixed, paraffin-embedded tissue from patients with intrahepatic cholangiocarcinoma (n = 23) and extrahepatic cholangiocarcinoma (n = 43). Hepatitis B surface antigen seropositivity was found in 52.2% (12/23) of intrahepatic cholangiocarcinoma cases and 13.9% (6/43) of extrahepatic cholangiocarcinoma cases. Hepatitis B virus DNA (X region) was detectable in 34.8% (8/23) of intrahepatic cholangiocarcinoma cases. Hepatitis B surface antigen and/or hepatitis B core antigen was detectable in 30.4% (7/23) of intrahepatic cholangiocarcinoma cases. All cases with detected viral protein were also positive for hepatitis B virus DNA. In contrast, no hepatitis B virus antigens or hepatitis B virus gene was detected in any of the 43 extrahepatic cholangiocarcinoma cases. Our findings strongly suggest that chronic hepatitis B virus infection is a significant risk factor for intrahepatic cholangiocarcinoma, but not for extrahepatic cholangiocarcinoma, in northern China. Hepatitis B virus infection is potentially independently associated with intrahepatic cholangiocarcinoma.

Single nucleotide polymorphism at exon 7 splice acceptor site of OAS1 gene determines response of hepatitis C virus patients to interferon therapy

BACKGROUND AND AIM

Response to interferon therapy and disease progression in hepatitis C virus (HCV) infected patients differs among individuals, suggesting a possibility of a contribution of host genetic factors. 2'-5'-oligoadenylate synthetase 1 (OAS1), an important component of the innate immune system with a proven antiviral function, may therefore have a relationship with the response to interferon therapy and clinical course of HCV disease. Our aim was to determine the frequency of single nucleotide polymorphism (SNP) at exon 7 splice acceptor site (SAS) of the OAS1 gene in relation to the interferon response and status of HCV infection.

METHODS

A 203 bp fragment containing exon 7 SAS was amplified in 70 HCV chronic patients and 50 healthy controls. SNP was examined using restriction fragment length polymorphism (RFLP) genotyping method. Correlations of SNP genotypes with response to interferon and clinical status of patients were statistically analyzed.

RESULTS

There was an increasing trend of response from AA to AG to GG genotypes (P = 0.007). Genotype AA was associated with non-response to interferon and higher degree of liver fibrosis (P = 0.05). Multivariate analysis showed this SNP as independent and a significant determinant of the outcome of interferon therapy (odds ratio 4.913 [95% confidence interval 1.365-8.2], P = 0.006).

CONCLUSIONS

This is the first study to show a significant association between the functional SNP at exon 7 SAS of OAS1 gene and the viral response to interferon in chronic HCV patients. Patients with AA genotype were associated with progressive HCV disease and viral resistance to interferon therapy. This OAS SNP is a potential bio-marker to predict IFN response in chronic hepatitis C patients.

Human cytomegalovirus infection inhibits response of chronic hepatitis-C-virus-infected patients to interferon-based therapy

BACKGROUND AND AIM

Cytomegalovirus (CMV) is a ubiquitous pathogen that infects the majority of humans. Co-infection of CMV and hepatitis C virus (HCV) may deteriorate the prognosis of HCV-infected patients. This study was conducted to examine the role of CMV reactivation in determining the response rate to treatment with interferon and ribavirin therapy in chronic HCV patients.

METHODS

Viral loads and genotyping were assessed using reverse transcription polymerase chain reaction and Innolipa systems, respectively. Reactivation of CMV in HCV patients who were all positive for CMV immunoglobulin G antibodies was tested by amplification of the gB1 gene using the end-point dilution quantitative-nested polymerase chain reaction method.

RESULTS

CMV DNA was detected in 89.7% of non-responders and in 34.6% of sustained virological responders. Patients with reactivated CMV had significantly higher fibrosis scores (72.7%) than those with undetectable CMV DNA (23.8%, P=0.002). Patients with positive CMV had higher rates of non-response and relapse (79.5%) than those with negative CMV DNA (19%). Chronic HCV patients with latent CMV had higher rates of response (81%) to treatment than those with reactivated CMV (20.5%, P<0.001). Therefore, HCV patients with reactivated CMV and advanced fibrosis were least likely to achieve a sustained virological response following interferon therapy. This possibility is reduced to 50% of its original value in patients with reactivated CMV without fibrosis.

CONCLUSIONS

Besides the staging of liver fibrosis, CMV co-infection should be considered as an extremely important factor when designing predictive models for HCV response to interferon treatment.