Influence of amino-acid polymorphism in the core protein on progression of liver disease in patients infected with hepatitis C virus genotype 1b

Complex Association of Virus- and Host-Related Factors with Hepatocellular Carcinoma Rate following Hepatitis C Virus Clearance

Little is known about the effects of virus- and host-related factors on hepatocarcinogenesis in patients who show viral clearance after HCV RNA eradication by direct-acting antivirals (DAAs). The subjects of this retrospective study were 1,922 patients with HCV genotype 1 (HCV-1)- or HCV-2-related chronic liver disease who showed a sustained virological response (SVR; defined as negative results for HCV RNA at 12 weeks after the cessation of all-oral DAAs). All patients were confirmed to be hepatocellular carcinoma (HCC) free before and during DAAs. HCC was diagnosed in 43 patients during the follow-up, with an incidence rate per 1,000 person years of 9.44. The cumulative HCC rates were 1.2, 2.0, and 3.1% at the end of 1, 2, and 3 years, respectively. The annual rate of HCC during the first 3 years was 1.0%. The incidence rate was significantly higher in patients infected with the HCV-1b core amino acid (aa) 70 mutant than in those infected with HCV-2a/2b, and the rate in patients infected with the HCV-1b core aa 70 wild type tended to be higher than that in patients infected with HCV-2a/2b. The rate in patients infected with the HCV-1b NS5A aa 93 mutant was significantly higher than that in patients infected with HCV-2a/2b. However, the rate was not different between patients infected with the IL28B rs8099917 TT genotype and patients infected with the non-TT genotype. Multivariate analysis identified a Wisteria floribunda agglutinin-positive Mac-2 binding protein (WFA⁺M2BP) cutoff index (COI) of ≥2.5 and infection with the HCV-1b core aa 70 mutant subgroup to be pretreatment predictors of posttreatment HCC. The same analysis identified an alpha-fetoprotein concentration of ≥5 μg/liter and an WFA⁺M2BP COI of ≥1.0 to be predictors of HCC at 24 weeks after the end of antiviral therapy. We conclude that both virus- and host-related factors seem to influence the development of HCC after HCV RNA eradication.

Polymorphisms in the hepatitis C virus core and its association with development of hepatocellular carcinoma

Little is known about the mechanisms underlying hepatocellular carcinoma (HCC). Some studies have focused on the role of HCV viral proteins in hepatocyte transformation. In this work we have compiled and analysed current articles regarding the impact of polymorphisms in the HCV core gene and protein on the development of HCC. An exhaustive search for fulltext articles until November 2016 in PubMed database was performed using the MeSH keywords: 'hepatitis C', 'polymorphisms', 'core', 'hepatocellular cancer' and 'hepatocarcinogenesis'. Nineteen full-text articles published between 2000 and 2016 were considered. Different articles associate not only the HCC development with polymorphisms at residues 70 and 91 in the core protein, but more with mortality and treatment response. Also, different polymorphisms were found in core and other viral proteins related to HCC development. Eleven articles reported that HCC development is significantly associated with Gln/His70, four associated it with Leu91 and two more associated it with both markers together. Additional studies are necessary, including those in different types of populations worldwide, to validate the possibility of the usability and influence in chronically HCV-infected patients as well as to observe their interaction with other risk factors or prognosis and genetic markers of the host.

Amino acid substitutions in the hepatitis C virus core region predict hepatocarcinogenesis following eradication of HCV RNA by all-oral direct-acting antiviral regimens

Impact of substitution of aa70 in the core region (Core aa70) in HCV genotype 1b (HCV-1b) on hepatocarcinogenesis following eradication of HCV RNA by direct-acting antiviral therapy is not clear. In a retrospective study, 533 patients with HCV-related chronic liver disease, with sustained virological response defined as negative HCV RNA at 12 weeks after cessation of direct-acting antiviral therapy, were examined to evaluate the relationship between Core aa70 substitution and hepatocarcinogenesis. Twelve patients developed hepatocellular carcinoma during the follow-up period. The cumulative hepatocarcinogenesis rates were 1.7% and 2.4% at the end of 1 and 2 years, respectively. Overall, multivariate analysis identified HCV subgroup (HCV-1b with Gln70(His70); P = 0.003) and age (>65 years; P = 0.049), as pretreatment predictors of hepatocarcinogenesis. In HCV-1b patients, multivariate analysis identified post-treatment Wisteria floribunda agglutinin positive Mac-2 binding protein (>1.8 COI; P = 0.042) and HCV subgroup (HCV-1b with Gln70(His70); P = 0.071), as predictors of hepatocarcinogenesis, including post-treatment parameter. In conclusion, Core aa70 substitution in HCV-1b at the start of direct-acting antiviral therapy is an important predictor of hepatocarcinogenesis following eradication of HCV RNA. This study emphasizes the importance of detection of Core aa70 substitution before initiating antiviral therapy.

Impact of hepatitis C virus core mutations on the response to interferon-based treatment in chronic hepatitis C

AIM

To determine whether hepatitis C virus (HCV) core substitutions play a role in the response to interferon-based treatment in Caucasian patients.

METHODS

One hundred eight HCV chronically infected patients initiating treatment with pegylated IFN plus ribavirin for 48 wk were tested for baseline substitutions at codons 70 and 91 of the viral core protein (BigDye Terminator vers.3.1, Applied Biosystems,) and for genetic polymorphisms in host IL28B gene rs12979860 (Custom TaqMan 5' allelic discrimination assay; Applied Biosystems).

RESULTS

Of the patients, all were infected with HCV genotype 1b, 44.4% had low baseline HCV viral load, and 37.9% had mild/moderate fibrosis. Only 38.9% achieved therapeutic success, defined as sustained virological response (SVR). Eighty-eight percent of the patients presented at least one substitution at core position 70 (R70Q/H) or/and position 91 (L91M). The favorable IL28B CC polymorphism was detected in only 17.6% of the patients. In the univariate analysis, young age (P < 0.001), urban residence (P = 0.004), IL28B CC genotype (P < 0.001), absence of core mutations (P = 0.005), achievement of rapid virologic response (P < 0.001) and early virological response (P < 0.001) were significantly correlated with SVR. A multivariate analysis revealed three independent predictors of therapeutic success: young age (P < 0.001), absence of core substitutions (P = 0.04) and IL28B CC genotype (P < 0.001); the model correctly classified 75.9% of SVR cases with a positive predictive value of 80.7%.

CONCLUSION

HCV core mutations can help distinguish between patients who can still benefit from the affordable IFN-based therapy from those who must be treated with DAAs to prevent the evolution towards end-stage liver disease.

Polymorphisms of the NS3 Proteins of Hepatitis C Virus Genotype 1b Are Associated with Liver Cirrhosis

Polymorphisms of the hepatitis C virus (HCV) core protein and NS3 have been described to be associated with liver cirrhosis (LC) and/or hepatocellular carcinoma in patients with chronic hepatitis C genotype 1b (HCV 1b). Here, we determine whether there is an association between LC and polymorphisms of viral core protein and NS3 in patients in Hubei province, China. A total of 42 patients with chronic HCV 1b (21 patients with LC and 21 with chronic hepatitis [CH]) were enrolled, amino acid sequence of the core protein and N-terminus of NS3 were obtained by direct sequencing and compared with the prototype strain HCV-J. No significant difference of amino acid polymorphisms was observed between isolates from LC and CH patients in the core protein. However, in the N-terminus of NS3, amino acid polymorphisms at positions A1072T (Ala 1072 chronic Thr 1072 cirrhosis), I1074V (Ile 1074 chronic Val 1074 cirrhosis), and T1098N/I (Thr 1098 chronic Asn or Ile 1098 cirrhosis) correlated significantly with LC. These findings indicate that the polymorphisms of HCV at these sites may be the risk factors for the development of LC in patients with chronic HCV 1b.

Interferon lambda and hepatitis C virus core protein polymorphisms associated with liver cancer

BACKGROUND

Hepatitis C virus (HCV) infection is often persistent and gradually advances from chronic hepatitis to liver cirrhosis and hepatocellular carcinoma (HCC). Worldwide, hepatocellular carcinoma is the fifth most common neoplasm.

METHOD OF STUDY

the Interferon lambda (IFNL) polymorphisms genotypes (rs8099917, rs12979860 and rs12980275) and the presence of mutations in HCV core protein were analyzed in 59 patients with HCC, and also in 50 cirrhotic patients (without HCC).

RESULTS

the rs12980275-AG genotype was associated with HCC on age-adjusted analysis (OR 2.42, 95% CI 1.03-5.69, P=0.043). Core substitutions R70Q and L91M were mainly found in genotype 1b isolates. Furthermore, a borderline level of statistical significance association was found among the presence of amino acid Glutamine (Q) in the position 70 and IFNL3 genotype AG (P=0.054).

CONCLUSIONS

the screening of these polymorphisms and functional studies would be useful in clinical practice for identifying groups at high risk of HCC development.

The Prevalence of Hepatitis C Virus Core Amino Acid 70 Substitution and Genotypes of Polymorphisms Near the IFNL3 Gene in Iranian Patients With Chronic Hepatitis C

BACKGROUND

Molecular studies have demonstrated that the hepatitis C virus (HCV) genotype and host genetics play predictive roles in the management of patients infected with HCV.

OBJECTIVES

This study aimed to investigate the HCV genotype, core amino acid (aa) 70 substitution, and polymorphisms near the IFNL3 gene (including rs12979860 and rs8099917) among Iranian patients with chronic hepatitis C (CHC).

PATIENTS AND METHODS

In this cross-sectional study, the molecular profiles of the HCV genotype, core aa 70 substitution, and rs12979860 and rs8099917 polymorphisms and plasma HCV RNA levels were determined in 429 CHC patients including 141 hemophilic, 84 thalassemic, and 204 non-hemophilic, non-thalassemic patients.

RESULTS

The hepatitis C virus subtype 1a was the most common subtype in the study population. Core aa substitution Arg70Gln was strongly associated with cirrhosis (OR = 2.49; 95% CI = 1.13 - 5.50; P = 0.020). Core aa 70 substitutions were more frequently observed in patients with the HCV subtype 1b than in patients with any other HCV subtypes (P < 0.001). Core aa 70 substitutions were also more common in patients with the rs12979860 TT genotype than in patients with non-TT genotypes (17.3% vs. 8.5%, P = 0.022) and also in rs8099917 non-TT genotypes than in the TT genotype (14.0% vs. 7.0%, P = 0.026). The HCV genotypes and rs8099917 polymorphisms were correlated in which HCV subtype 1b was in favor of rs8099917 GG and HCV subtype 3a favored rs8099917 TT (P = 0.021). Furthermore, the rs12979860 TT and rs8099917 GG genotypes showed significantly lower HCV RNA levels than the other genotypes (P < 0.001).

CONCLUSIONS

There is an as yet unexplained association between HCV and host parameters with unknown mechanisms in patients with chronic HCV infection. The assessments of core aa 70 substitution and polymorphisms near the IFNL3 gene could offer promising steps to improve the management of patients with HCV.

Hepatitis C virus Genotype 1a core gene nucleotide patterns associated with hepatocellular carcinoma risk

Specific sequence changes in codons 70 and 91 of the hepatitis C virus genotype 1b (HCV GT1b) core gene have been associated with increased risk of hepatocellular carcinoma (HCC). Essentially all previous studies were conducted in Asian populations with a wide range of liver disease, and none were conducted specifically in GT1a-infected individuals. We conducted a pilot study in a multiethnic population in the USA with HCV-related cirrhosis to determine if this association extended to GT1a-infected individuals and to determine if other sequence changes in the HCV core gene were associated with HCC risk. HCV core gene sequences from sera of 90 GT1 HCV carriers with cirrhosis (42 with HCC) were analysed using standard RT-PCR-based procedures. Nucleotide sequence data were compared with reference sequences available from GenBank. The frequency of sequence changes in codon 91 was not statistically different between HCC (7/19) and non-HCC (11/22) GT1b carriers. In GT1a carriers, sequence changes in codon 91 were observed less often than in GT1b carriers but were not observed in non-HCC subjects (4/23 vs 0/26, P = 0.03, Fisher's exact test). Sequence changes in codon 70 were not distributed differently between HCC and non-HCC GT1a and 1b carriers. Most importantly, for GT1a carriers, a panel of specific nucleotide changes in other codons was collectively present in all subjects with HCC, but not in any of the non-HCC patients. The utility of this test panel for early detection of HCC in GT1a-infected individuals needs to be assessed in larger populations, including longitudinal studies.

Impact of Mutations at Amino Acid 70 in Hepatitis C Virus (HCV) Genotype 1b Core Region on Hepatocarcinogenesis following Eradication of HCV RNA

The impact of the HCV genotype 1b core amino acid (aa) 70 mutant on the cumulative rate of hepatocellular carcinoma following eradication of HCV RNA by antiviral therapy was investigated with the Q-Invader assay. Multivariate analysis based on 649 patients indicated that a core aa70 Q-Invader mutant level ≥20% is a predictor of hepatocellular carcinoma.

HCV genome-wide genetic analyses in context of disease progression and hepatocellular carcinoma

Hepatitis C virus (HCV) is a major cause of hepatitis and hepatocellular carcinoma (HCC) world-wide. Most HCV patients have relatively stable disease, but approximately 25% have progressive disease that often terminates in liver failure or HCC. HCV is highly variable genetically, with seven genotypes and multiple subtypes per genotype. This variation affects HCV's sensitivity to antiviral therapy and has been implicated to contribute to differences in disease. We sequenced the complete viral coding capacity for 107 HCV genotype 1 isolates to determine whether genetic variation between independent HCV isolates is associated with the rate of disease progression or development of HCC. Consensus sequences were determined by sequencing RT-PCR products from serum or plasma. Positions of amino acid conservation, amino acid diversity patterns, selection pressures, and genome-wide patterns of amino acid covariance were assessed in context of the clinical phenotypes. A few positions were found where the amino acid distributions or degree of positive selection differed between in the HCC and cirrhotic sequences. All other assessments of viral genetic variation and HCC failed to yield significant associations. Sequences from patients with slow disease progression were under a greater degree of positive selection than sequences from rapid progressors, but all other analyses comparing HCV from rapid and slow disease progressors were statistically insignificant. The failure to observe distinct sequence differences associated with disease progression or HCC employing methods that previously revealed strong associations with the outcome of interferon α-based therapy implies that variable ability of HCV to modulate interferon responses is not a dominant cause for differential pathology among HCV patients. This lack of significant associations also implies that host and/or environmental factors are the major causes of differential disease presentation in HCV patients.

Impact of hepatitis C virus heterogeneity on interferon sensitivity: an overview

Hepatitis C virus (HCV) is a major cause of liver disease worldwide. HCV is able to evade host defense mechanisms, including both innate and acquired immune responses, to establish persistent infection, which results in a broad spectrum of pathogenicity, such as lipid and glucose metabolism disorders and hepatocellular carcinoma development. The HCV genome is characterized by a high degree of genetic diversity, which can be associated with viral sensitivity or resistance (reflected by different virological responses) to interferon (IFN)-based therapy. In this regard, it is of importance to note that polymorphisms in certain HCV genomic regions have shown a close correlation with treatment outcome. In particular, among the HCV proteins, the core and nonstructural proteins (NS) 5A have been extensively studied for their correlation with responses to IFN-based treatment. This review aims to cover updated information on the impact of major HCV genetic factors, including HCV genotype, mutations in amino acids 70 and 91 of the core protein and sequence heterogeneity in the IFN sensitivity-determining region and IFN/ribavirin resistance-determining region of NS5A, on virological responses to IFN-based therapy.

Production and pathogenicity of hepatitis C virus core gene products

Hepatitis C virus (HCV) is a major cause of chronic liver diseases, including steatosis, cirrhosis and hepatocellular carcinoma, and its infection is also associated with insulin resistance and type 2 diabetes mellitus. HCV, belonging to the Flaviviridae family, is a small enveloped virus whose positive-stranded RNA genome encoding a polyprotein. The HCV core protein is cleaved first at residue 191 by the host signal peptidase and further cleaved by the host signal peptide peptidase at about residue 177 to generate the mature core protein (a.a. 1-177) and the cleaved peptide (a.a. 178-191). Core protein could induce insulin resistance, steatosis and even hepatocellular carcinoma through various mechanisms. The peptide (a.a. 178-191) may play a role in the immune response. The polymorphism of this peptide is associated with the cellular lipid drop accumulation, contributing to steatosis development. In addition to the conventional open reading frame (ORF), in the +1 frame, an ORF overlaps with the core protein-coding sequence and encodes the alternative reading frame proteins (ARFP or core+1). ARFP/core+1/F protein could enhance hepatocyte growth and may regulate iron metabolism. In this review, we briefly summarized the current knowledge regarding the production of different core gene products and their roles in viral pathogenesis.

Genetic variability of hepatitis B and C viruses in Brazilian patients with and without hepatocellular carcinoma

Most cases of hepatocellular carcinoma (HCC) are due to chronic hepatitis B virus (HBV) or hepatitis C virus (HCV) infection worldwide. The aim of this study was to determine the viral genotypes and frequency of 17 mutations (15 for HBV and 2 for HCV), described previously as able to influence the course of chronic liver disease, in patients with and without HCC. This transversal study included 157 Brazilian patients with chronic hepatitis B (n = 51) and C (n = 106). Of these, 12 and 40 patients had HBV- and HCV-related HCC, respectively. Nucleotide sequencing of core promoter, pre-core, and pre-S/S regions of HBV and core region of HCV strains was performed to determine their genotypes and the frequency of the respective mutations. Among the HBV isolates, subgenotype A1 was the most prevalent in both patients with (90%) and without (61%) HCC. Fourteen out of the 15 mutations under study, as well as five different pre-S deletions, were identified. Core promoter T1753V, A1762T, and G1764A mutations were more frequent in patients with HCC than in those without, although with no statistical difference. However, a significant correlation was observed between T1753V mutation and elevation of transaminases levels (P < 0.05). As for HCV, mutation at residue 70 in the core protein of genotype 1b strains was significantly more frequent in patients with cirrhosis (56.3%) than in those without (9.1%) (P = 0.018). The detection of some key mutations in the genomes of HBV and HCV might be helpful to predict the clinical outcome of patients with chronic liver disease.

Polymorphisms of the core, NS3, and NS5A proteins of hepatitis C virus genotype 1b associate with development of hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is one of the common sequelae of hepatitis C virus (HCV) infection. It remains controversial, however, whether HCV itself plays a direct role in the development of HCC. Although HCV core, NS3, and NS5A proteins were reported to display tumorigenic activities in cell culture and experimental animal systems, their clinical impact on HCC development in humans is still unclear. In this study we investigated sequence polymorphisms in the core protein, NS3, and NS5A of HCV genotype 1b (HCV-1b) in 49 patients who later developed HCC during a follow-up of an average of 6.5 years and in 100 patients who did not develop HCC after a 15-year follow-up. Sequence analysis revealed that Gln at position 70 of the core protein (core-Gln(70) ), Tyr at position 1082 plus Gln at 1112 of NS3 (NS3-Tyr(1082) /Gln(1112) ), and six or more mutations in the interferon/ribavirin resistance-determining region of NS5A (NS5A-IRRDR≥6) were significantly associated with development of HCC. Multivariate analysis identified core-Gln(70) , NS3-Tyr(1082) /Gln(1112) , and α-fetoprotein (AFP) levels (>20 ng/L) as independent factors associated with HCC. Kaplan-Meier analysis revealed a higher cumulative incidence of HCC for patients infected with HCV isolates with core-Gln(70) , NS3-Tyr(1082) /Gln(1112) or both than for those with non-(Gln(70) plus NS3-Tyr(1082) /Gln(1112) ). In most cases, neither the residues at position 70 of the core protein nor positions 1082 and 1112 of the NS3 protein changed during the observation period.

CONCLUSION

HCV isolates with core-Gln(70) and/or NS3-Tyr(1082) /Gln(1112) are more closely associated with HCC development compared to those with non-(Gln(70) plus NS3-Tyr(1082) /Gln(1112) ).

Prevalence of amino acid mutations in hepatitis C virus core and NS5B regions among Venezuelan viral isolates and comparison with worldwide isolates

BACKGROUND

Recent reports show that R70Q and L/C91M amino acid substitutions in the core from different hepatitis C virus (HCV) genotypes have been associated with variable responses to interferon (IFN) and ribavirin (RBV) therapy, as well to an increase of hepatocellular carcinoma (HCC) risk, liver steatosis and insulin resistance (IR). Mutations in NS5B have also been associated to IFN, RBV, nucleoside and non-nucleoside inhibitors drug resistance. The prevalence of these mutations was studied in HCV RNA samples from chronically HCV-infected drug-naïve patients.

METHODS

After amplification of core and NS5B region by nested-PCR, 12 substitutions were analyzed in 266 Venezuelan HCV isolates subtype 1a, 1b, 2a, 2c, 2b, 2j (a subtype frequently found in Venezuela) and 3a (n = 127 and n = 228 for core and NS5B respectively), and compared to isolates from other countries (n = 355 and n = 646 for core and NS5B respectively).

RESULTS

R70Q and L/C91M core substitutions were present exclusively in HCV G1b. Both substitutions were more frequent in American isolates compared to Asian ones (69% versus 26%, p < 0.001 and 75% versus 45%, p < 0.001 respectively). In Venezuelan isolates NS5B D310N substitution was detected mainly in G3a (100%) and G1a (13%), this later with a significantly higher prevalence than in Brazilian isolates (p = 0.03). The NS5B mutations related to IFN/RBV treatment D244N was mainly found in G3a, and Q309R was present in all genotypes, except G2. Resistance to new NS5B inhibitors (C316N) was only detected in 18% of G1b, with a significantly lower prevalence than in Asian isolates, where this polymorphism was surprisingly frequent (p < 0.001).

CONCLUSIONS

Genotypical, geographical and regional differences were found in the prevalence of substitutions in HCV core and NS5B proteins. The substitutions found in the Venezuelan G2j type were similar to that found in G2a and G2c isolates. Our results suggest a high prevalence of the R70Q and L/C91M mutations of core protein for G1b and D310N substitution of NS5B protein for the G3a. C316N polymorphism related with resistance to new NS5B inhibitors was only found in G1b. Some of these mutations could be associated with a worse prognosis of the disease in HCV infected patients.

Impact of HCV genetic differences on pathobiology of disease

Multiple HCV genotypes have been isolated worldwide. Genotype seems to be involved in the main pathological aspects of HCV infection. Insulin resistance, steatosis and progression toward cirrhosis, fibrosis and hepatocellular carcinoma establish and develop following genotype-specific mechanisms. Moreover genotype influences pharmacological treatment in term of dose and duration. Pathways involved in cell proliferation, apoptosis, lipid metabolism, insulin and interferon signaling are impaired to a different extent among genotypes, leading to distinct pathological settings. Genotype 1 is associated with a more aggressive disease with increased insulin resistance, worst response to therapy, higher risk of cirrhosis and hepatocellular carcinoma development, while genotype 3 is associated with increased steatosis and fibrosis. The identification and characterization of HCV types and subtypes provides insight into the different outcome of HCV infection and responsiveness to therapy. In the present article, we focused on the pathogenicity of HCV genotypes and their effect on disease progression and treatment.

Antiviral combination therapy with peginterferon and ribavirin does not induce a therapeutically resistant mutation in the HCV core region regardless of genetic polymorphism near the IL28B gene

An association has been reported between genetic polymorphism near IL28B gene and the prevalence of mutation of hepatitis C virus (HCV) core region residue 70, both of which have been associated with a lack of virologic response to antiviral combination therapy with peginterferon (PEG-IFN) and ribavirin. This study investigated whether PEG-IFN/ribavirin combination therapy induces amino acid (AA) mutation at residue 70 of HCV and whether genetic polymorphism near IL28B gene affects it. AA substitutions at residue 70 of the HCV core region were measured and compared before and after combination therapy in 65 non-responders and 88 relapsers to the combination therapy. In three patients in whom both wild-type AA (arginine) and mutant-type AA (glutamine or histidine) were detected at residue 70 before treatment, only mutant-type AA was identified after treatment. In two patients who had wild-type AA solely before treatment, both wild-type and mutant-type AAs were identified at residue 70 after treatment. In five patients, in whom the AA had changed at residue 70 between before and after treatment, four patients carried the TT genotype at a polymorphic locus (rs8099917) near the IL28B gene and one carried the TG/GG genotype. No difference was found in the prevalence of this change of AA at residue 70 between the TT and the TG/GG genotype. Antiviral combination therapy with PEG-IFN and ribavirin does not appear to induce mutation of HCV core region residue 70 regardless of genetic polymorphism near the IL28B gene in Japanese patients infected with HCV genotype 1b.

Analysis of viral amino acids sequences and the IL28B SNP influencing the development of hepatocellular carcinoma in chronic hepatitis C

BACKGROUND AND AIMS

The association between hepatitis C virus (HCV) sequences with interleukin 28B (IL28B) single-nucleotide polymorphism (SNP) in the development of hepatocellular carcinoma (HCC) has not been well clarified.

METHODS

Complete HCV open-reading frame sequences were determined in 20 patients developing HCC and 23 non-HCC patients with HCV-1b infection in two distant time points. An additional 230 patients were studied cross-sectionally for core and NS5A sequences with HCC development. Among them, 98 patients with available samples were investigated for changes in viral core sequences over time. Finally, IL28B SNPs and HCC development were investigated in 228 patients.

RESULTS

During observation period (HCC for 10.8 years, and non-HCC for 11.1 years), changes in core a.a. 70 and three amino acid positions in NS5A were characteristics of the patients developing HCC. In 230 patients, Q (glutamine) or H (histidine) to R (arginine) ratio at core a.a. 70 was significantly higher in the HCC group (HCC group 43:22 vs. non-HCC group 66:99, p = 0.001). A change in core R70Q was observed over time in 11 patients associated with a decrease in platelets (p = 0.005) and albumin (p = 0.005), while a Q70R change was observed in 4 patients without associated changes in platelets (nonsignificant) and albumin (nonsignificant). IL28B SNP showed significant correlation with the core a.a. 70 residue. There was no evident link between IL28B SNPs and the occurrence of HCC.

CONCLUSIONS

Hepatitis C virus core a.a. 70 residue is associated with liver disease progression and is independent factor for HCC development in genotype-1b infection. IL28B SNPs are related to core a.a. 70 residue, but not to HCC. The functional relevance of core a.a. 70 residue in hepatitis C pathogenesis should be further investigated.