A.M. Bozdayi

Molecular epidemiology of hepatitis B, C and D viruses in Turkish patients

Summary.Different genotypes of the hepatitis viruses may influence the clinical outcome of the disease. The distribution of genotypes may vary according to geographical regions. The aim of this study was to evaluate hepatitis B virus (HBV), hepatitis C virus (HCV) and hepatitis D virus (HDV) genotypes in Turkish patients with chronic hepatitis in a large cohort of patients. Genotyping was performed in 41, 59 and 365 patients with chronic hepatitis B, D and C, respectively, and 36 hemodialysis patients with chronic hepatitis C. Genotypes were determined by direct sequencing in hepatitis B and by polymerase chain reaction-restriction fragment length polymorphism in hepatitis C and D patients. In addition, HBV subtyping by multiplex PCR and subtype specific ELISA were performed in 83 and 71 HBsAg (+) blood donors, respectively. All hepatitis B (100%) and hepatitis D (100%) patients had genotype D and type I, respectively. HBsAg subtyping by two methods yielded that 99% of the patients were subtype ayw. S gene amino acid sequence in the 41 patients included for HBV genotyping revealed the ayw2 subtype. Genotype distribution of 365 patients with chronic C hepatitis were as follows: 306 (84%) patients genotype 1b, 43 (11%) patients genotype 1a, 10 (3%) patients genotype 2, 3 (1%) patients genotype 3, 3 (1%) patients genotype 4. Among 36 patients receiving hemodialysis, 28 (78%) patients had genotype 1b and 8 (22%) patients had genotype 1a. The study indicates that Turkish patients with chronic viral hepatitis show very little genotypic heterogeneity. Subtype ayw and the genotype D of HBV DNA, and the type I of HDV RNA represent almost 100% of related infections. The genotype 1b of HCV RNA was found to be significantly dominant in Turkish patients.

Treatment of chronic delta hepatitis with lamivudine vs lamivudine + interferon vs interferon

Summary.  Chronic delta hepatitis is the most severe form of chronic viral hepatitis for which interferon (IFN) is the only available treatment. In 39 patients (25 were treatment‐naïve, 14 had previously used IFN), efficacy of 1‐year treatment with IFN (9 MU, t.i.w.) or lamivudine (LAM; 100 mg, q.d.) alone was compared with IFN and LAM combination (2 months of LAM to be followed by combination treatment). IFN monotherapy was given only to treatment‐naïve patients. In both treatment‐naïve and previous IFN users, end of treatment virological and biochemical responses were similar with IFN–LAM combination and superior to LAM monotherapy (P < 0.05). Improvement in liver histology occurred more often with IFN ± LAM than with LAM alone (P < 0.05). In treatment‐naïve patients, combination treatment was not superior to IFN monotherapy. After treatment discontinuation, virological and biochemical response rates decreased in LAM and IFN combination and IFN monotherapy. On treatment virological response at month 6 of treatment predicted sustained virological response. The results of this study suggest that addition of LAM to IFN for the treatment of delta hepatitis is of no additional value and that both treatment modalities are superior to LAM monotherapy.

Cytotoxic CD4 T cells in viral hepatitis.

Summary.  CD4+ T cells are thought to contribute to antiviral immune responses by secretion of cytokines thereby providing help to CD8+ T and B cells. However, perforin‐positive cytotoxic CD4+ T cells have been described in human immunodeficiency virus‐positive patients suggesting a role not only of CD8+ but also of CD4+ T cells for killing virus‐infected cells. We investigated 76 patients with viral hepatitis [15 hepatitis B virus (HBV), 22 HBV/hepatitis D virus and 17 hepatitis C virus (HCV)] for cytotoxic CD4+ T cells. The frequency of perforin‐positive CD4+ T cells in viral hepatitis was highly variable ranging from <1% to more than 25%. Perforin‐positive CD4+ T cells displayed the phenotype of terminally differentiated effector cells (CD28−, CD27−). The highest frequencies of CD4+ cytotoxic T lymphocytes (CTLs) were found in patients with delta hepatitis (P = 0.04 vs HBV and HCV patients), and the presence of CD4+ CTLs was associated with elevated aspartate aminotransferase levels (P = 0.01) and decreased platelet counts (P = 0.03). Perforin‐positive CD4+ T cells decreased in two individuals during spontaneous clearance of acute hepatitis C. Significant associations were found between the frequency of perforin‐expressing CD4+ cells and age (P = 0.04), perforin‐positive CD8+ cells (P < 0.001) and perforin‐positive CD4−/CD8− lymphoid cells (P = 0.002). Differentiated CD27− effector CD4+ CTLs can be detected in patients with viral hepatitis. In particular in patients with more advanced liver disease, the accumulation of perforin‐positive T cells with age could be one correlate for the more severe course of viral hepatitis in elderly individuals.

Natural history and treatment of chronic delta hepatitis

Summary.  Chronic delta hepatitis (CDH) represents a severe form of chronic viral hepatitis, induced by the hepatitis delta virus (HDV) in conjunction with the hepatitis B virus (HBV). Delta hepatitis may lead to disease in humans through co‐infection. The former leads to acute hepatitis which clinically can range from mild hepatitis to fulminant hepatitis and death. Severe or fulminant hepatitis is more often observed with HBV‐HDV co‐infection compared to HBV mono‐infection. Chronic infection after acute hepatitis B + D co‐infection is infrequent and similar to the rate in mono‐infected patients. CDH develops in 70–90% of patients with superinfection. CDH runs a more progressive course than chronic hepatitis B and may lead to cirrhosis within 2 years in 10–15% of patients. However, as with any immune‐mediated disease, different patterns of progression, ranging from mild to severe progressive disease, are observed. Active replication of both HBV and HDV may be associated with a more progressive disease pattern. Further, different HDV and HBV genotypes may contribute to various disease outcomes. CDH may be frequently associated with hepatocellular carcinoma development although recent studies provided conflicting results. The only established therapy for CDH is treatment with interferons for a duration of at least 1 year. On treatment, 6 month HDV RNA assessment may give clues as to whether to stop treatment at 1 year or continue beyond 1 year. New approaches to treatment of CDH are an urgent need of which the use of prenylation inhibitors appears the most promising.

YSDD: a novel mutation in HBV DNA polymerase confers clinical resistance to lamivudine.

Summary.  The emergence of drug‐resistant virus in hepatitis B virus (HBV) patients treated with lamivudine is well documented. In this study, we determined the mutations occurring in the tyrosine–methionine–aspartate–aspartate (YMDD) amino acid motif of the HBV DNA polymerase gene, as well as upstream and downstream of this region, in patients with breakthrough virus during lamivudine therapy. Thirty‐one Turkish patients (20 patients HBeAg positive, 11 patients HBeAg negative and anti‐HBe positive) with chronic HBV infection who completed at least 104 weeks of lamivudine treatment were investigated. All patients received lamivudine, (150 mg/day), for 104 weeks, with or without 4 months of interferon (IFN) combination. HBV‐specific sequences were amplified by polymerase chain reaction (PCR) from sera of patients with breakthrough virus, and the PCR products were directly analysed by sequencing. Breakthrough virus was detected in seven of the 31 patients (22.6%) between 9 and 18 months of therapy. Of the seven patients, six were HBeAg positive at baseline, and four had a double mutation consisting of rtM204V and rtL180M, while two had an rtM204I change. In one patient, two base substitutions at rt204 (ATG → AGT; T to G and G to T) lead to a methionine to serine change (YMDD → YSDD). This novel DNA pol mutation was detected at month 18 of lamivudine treatment. In addition, this new variant had the rtL180M mutation and a 12 base pair deletion in the pre‐S1 region between nucleotides 43–54. The YSDD mutation was still present 6 months after lamivudine discontinuation.In vitro transfection studies also confirmed that the YSDD strain is resistant to lamivudine. In conclusion, the results indicate that, in addition to a Met → Val and Met → Ile change in YMDD, a Met → Ser change at rt204 (YMDD → YSDD) associated with the rtL180M change can also emerge during lamivudine treatment, which confers lamivudine resistance in vivo and in vitro, leading to virological breakthrough and ALT increases.

Thrombophilic gene mutations in cirrhotic patients with portal vein thrombosis.

Objective Thrombophilic gene mutations have been reported to be associated with the formation of portal vein thrombosis (PVT). This study aimed to investigate the role of thrombophilic gene mutations in cirrhotic patients with PVT. Patients and methods A total of 74 cirrhotic patients (17 with PVT, 57 without PVT), and 19 non-cirrhotic patients with PVT and 80 healthy controls were included. Factor V Leiden G1691A, prothrombin G20210A and methylenetetrahydrofolate reductase C677T mutations were analysed by restriction fragment length polymorphism. Results Aetiologies and Child–Pugh distribution of cirrhotic patients with and without PVT were similar. Five of 17 (29%) of cirrhotic patients with PVT but only two of 57 (3.5%) of cirrhotics without PVT, five of 80 (6%) of controls and none of the 19 non-cirrhotic patients with PVT had factor V Leiden G1691A mutation (P<0.05). Prothrombin G20210A mutation was found in five (29%) cirrhotic patients with PVT while only two (3.5%) cirrhotic patients without PVT, one (5%) non-cirrhotic patient with PVT and two (2.5%) controls had this mutation (P<0.05). The frequency of the homozygote methylenetetrahydrofolate reductase 677C-T mutation was similar in all four groups. Conclusions Inherited thrombophilic gene mutations appear to increase the risk of PVT formation in cirrhotic patients but not in patients without liver disease in a cohort of Turkish patients.

A pilot study of 2 years of interferon treatment in patients with chronic delta hepatitis

Summary.  High dose interferon treatment for 1 year is the only established treatment for chronic hepatitis D, but it is associated with a high relapse rate after treatment discontinuation. In this study, patients were treated with 10 MU interferon alpha 2b, thrice weekly for 2 years. Twenty‐three patients were recruited and 15 completed the 2‐year treatment and 6 months follow‐up periods. Treatment response was assessed biochemically [normal alanine aminotransferase (ALT)], virologically (undetectable hepatitis D virus RNA) and histologically (at least 2 point decrease in the Knodell score) at the end of treatment (EOT) and at the end of follow‐up. Out of 15 patients who finished the 2‐year treatment period, seven patients (47%) had a biochemical response but only two (13%) had a normal ALT after follow‐up. ALT decreased from the baseline value of 143.1 ± 121.7 (mean ± SD) to 39.7 ± 20.6 (P < 0.01) at EOT. Virological response was observed in six patients at EOT and in two patients at follow‐up. Two patients lost hepatitis B surface antigen. Of the 12 patients with paired liver biopsies, a histological improvement was observed in eight patients. Interferon treatment leads to a complete or partial response in a substantial number of patients but 2 years of treatment does not appear to increase sustained response rates over 1 year treatment.

Lamivudine vs lamivudine and interferon combination treatment of HBeAg(−) chronic hepatitis B

Summary.  To determine whether combination treatment of HBeAg(−) chronic hepatitis B is beneficial we studied 78 patients with HBeAg(−), HBV DNA‐positive chronic hepatitis B who were randomized to lamivudine, 100 mg, qd, for 12 months or lamivudine–interferon (9 MU, t.i.w.) in combination. In the combination arm, 2 months of lamivudine treatment preceded 10 months of combination treatment. Biochemical, virologic and histologic responses were assessed at the end of treatment, after six and a median 27 months of drug‐free follow‐up (short‐ and long‐term follow‐up, respectively). Virologic response was defined as undetectable HBV DNA with a hybridization assay and biochemical response as normal alanine aminotransferase (ALT). Change in HBV DNA was also assessed by real‐time polymerase chain reaction (PCR). Presence of YMDD mutants at the end of treatment was investigated with a line probe assay. Both treatment regimes led to a median 2 log decline in HBV DNA levels. Virologic end of treatment responses were 90 and 92% with mono‐ and combination treatment, respectively. Corresponding virologic responses at short‐ and long‐term follow‐up were 59 and 54%, and 27 and 25%, respectively. Patients having a baseline HBV DNA value ≥200 pg/mL were more likely to relapse within 6 months off therapy than those patients with a baseline HBV DNA level <200 pg/mL (P = 0.041). YMDD mutants were observed in 53% of patients receiving lamivudine compared with 24% of patients receiving the combination regime (P = 0.017). In conclusion, efficay of combination treatment is similar to lamivudine monotherapy. However, combination treatment decreases the development of YMDD mutant strains compared with lamivudine monotherapy.

Effect of Turkish propolis extracts on proteome of prostate cancer cell line

BackgroundPropolis is a natural, resinous hive product that has several pharmacological activities. Its composition varies depending on the vegetation, climate, season and environmental conditions of the area from where it was collected. Surface enhanced laser desorption ionization time of flight mass spectrometry (SELDI-TOF MS) is a proteomic approach which has been used in cancer proteomics studies. Prostate cancer is one of the most commonly diagnosed cancers in men. It has shown that nutritional supplements rich in polyphenolic compounds such as propolis play a significant role in prostate cancer chemoprevention. The aim of this study is to evaluate if protein expression profile in PC-3 prostate cancer cell lines could be differentiated when incubated with dimethyl sulfoxide and water extracts of Turkish propolis.ResultsThe antioxidant potentials of dimethyl sulfoxide and water extracts of propolis were found in correlation with the amount of total phenolic compounds of them. Dimethyl sulfoxide and water extracts of propolis of 20 μg/mL reduced the cell viability to 24.5% and 17.7%, respectively. Statistically significant discriminatory peaks between control PC-3 cells and dimethyl sulfoxide extract of propolis-treated PC-3 cells were found to be the proteomic features at m/z 5143, 8703, 12661, 20184 and 32794, detected by CM10 ProteinChip, and the peak at m/z 3772, detected by Q10 ProteinChip. Between control PC-3 cells and water extract of propolis-treated PC-3 cells, statistically significant discriminatory peaks were found to be the proteomic features at m/z 15846, 16052 and 24658, detected by CM10 ProteinChip and the peaks at m/z 10348, 10899 and 11603, detected by Q10 ProteinChip.ConclusionsIt was concluded that dimethyl sulfoxide and water extracts of Turkish propolis may have anti-proliferative activity through differentiating protein expression profile in PC-3 prostate cancer cell lines along with their antioxidant capacity.

Polymorphism of Precore Region of Hepatitis B Virus DNA among Patients with Chronic HBV Infection in Turkey

SummaryThe prevalence of mutations in the precore and core promoter regions of hepatitis B virus DNA and the association with the hepatitis B e antigen-negative phenotype vary in different geographical areas. It is rather high especially in the Far East and Mediterranean countries. The mutations occurring in the precore and the minimal essential region of the core promoter of HBV-DNA were analyzed in the sera of 81 patients (HBeAg-positive, 47 patients; HBeAg-negative, 34 patients) with chronic hepatitis B virus infection by direct sequencing of amplified polymerase chain reaction products.All patients had thymine at nucleotide 1858. Seven of 47 HBeAg-positive patients (15%) and 29 of 34 HBeAg-negative patients (85%) had precore stop codon mutations (G to A change at nucleotide 1896). No nucleotide change was found in the minimal essential region of HBV core promoter in any patient studied. In conclusion, the hepatitis B e antigen-negative phenotype in Turkish patients with chronic hepatitis B is associated with mutations in the precore but not in the minimal essential region of the core promoter. These results representing a part of the eastern Mediterranean support the studies conducted for the other populations of the region.