Hepatitis C virus-related mixed cryoglobulinemia: is genetics to blame?

Mixed cryoglobulinemia (MC) is the extrahepatic manifestation most strictly correlated with hepatitis C virus (HCV) infection; it is a benign autoimmune and lymphoproliferative disorder that evolves to lymphoma in 5%-10% of cases. MC is reputed to be a multistep and multifactorial process whose pathogenicity is still poorly understood. It is still unknown why only some chronically infected HCV patients develop MC and only some of these exhibit systemic symptoms (MC syndrome). Several studies have investigated the pathogenetic basis of MC and the most recent ones suggest that the virus is able to trigger such a disorder only in the presence of genetic factors that are still unknown. Here, we try to clarify the complex relationship between HCV-related MC and the host's genetic background. The data that we report are heterogeneous and sometimes even conflicting. Therefore, large, multicenter studies are clearly needed. The identification of a characteristic genetic signature of cryoglobulinemic patients would be an important step toward a personalized approach in their clinical care. The new wide-ranging genomics technologies will hopefully help to resolve these complex issues

Hepatitis C-associated B-cell non-Hodgkin lymphomas: The emerging role of miRNA-26b

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MicroRNA expression in hepatitis C virus-related malignancies: A brief review

Not only is chronic hepatitis C virus (HCV) infection a major public health problem, but also it can cause hepatocellular carcinoma and, more rarely, non-Hodgkin’s lymphoma. These characteristics mean that HCV is the only virus infecting humans that is able to cause two different cancers. The fine pathogenetic and molecular mechanisms by which HCV induces these two malignancies are not completely clear. In the last decade, it has been shown that microRNAs (miRNAs), a class of 21-23-nucleotide molecules modulating post-transcriptional gene expression, make an important contribution to the pathogenesis of several cancers and are also considered highly promising biomarkers. Here, we briefly describe the current knowledge about microRNAs’ involvement in HCV-related molecular oncogenesis. We decided to focus our attention on studies fully conducted on ex vivo samples with this specific etiology, and on cultured cell lines partially or completely expressing the HCV genome. Some of the results reported in this review are controversial, possibly because of methodological issues, differences in sampling size and features, and ethnicity of patients. What is certain is that miRNAs play a remarkable role in regulating gene expression during oncogenetic processes and in viral infection. A clear understanding of their effects is fundamental to elucidating the mechanisms underlying virus-induced malignancies

Hepatitis C virus syndrome: A constellation of organ- and non-organ specific autoimmune disorders, B-cell non-Hodgkin's lymphoma, and cancer

The clinical course of chronic hepatitis C virus (HCV) infection is characterized by possible development of both liver and extrahepatic disorders. The tropism of HCV for the lymphoid tissue is responsible for several immune-mediated disorders; a poly-oligoclonal B-lymphocyte expansion, commonly observed in a high proportion of patients with HCV infection, are responsible for the production of different autoantibodies and immune-complexes, such as mixed cryoglobulins. These serological alterations may characterize a variety of autoimmune or neoplastic diseases. Cryoglobulinemic vasculitis due to small-vessel deposition of circulating mixed cryoglobulins is the prototype of HCV-driven immune-mediated and lymphoproliferative disorders; interestingly, in some cases the disease may evolve to frank malignant lymphoma. In addition, HCV shows an oncogenic potential as suggested by several clinico-epidemiological and laboratory studies; in addition to hepatocellular carcinoma that represents the most frequent HCV-related malignancy, a causative role of HCV has been largely demonstrated in a significant percentage of patients with isolated B-cells non-Hodgkin's lymphomas. The same virus may be also involved in the pathogenesis of papillary thyroid cancer, a rare neoplastic condition that may complicate HCV-related thyroid involvement. Patients with HCV infection are frequently asymptomatic or may develop only hepatic alteration, while a limited but clinically relevant number can develop one or more autoimmune and/or neoplastic disorders. Given the large variability of their prevalence among patients' populations from different countries, it is possible to hypothesize a potential role of other co-factors, i.e., genetic and/or environmental, in the pathogenesis of HCV-related extra-hepatic diseases

Long-term effect of HCV eradication in patients with mixed cryoglobulinemia: A prospective, controlled, open-label, cohort study

Limited data are available about the efficacy of antiviral treatment in hepatitis C virus (HCV)-associated mixed cryoglobulinemia (MC), especially concerning the long-term effects of HCV eradication. The aim of this study was to evaluate the influence of MC on the virological response and the long-term effects of viral eradication on MC. We prospectively enrolled 424 HCV+ patients belonging to the following groups: MCS-HCV (121 patients with symptomatic MC); MC-HCV (132 patients with asymptomatic MC); HCV group (158 patients without MC). Peg-IFN+RBV treatment was administered according to standard protocols. Post-treatment follow-up ranged from 35 to 124 months (mean: 92.5 months). A significant difference was observed in the rate of sustained virological response (SVR) between HCV and both MC-HCV (p=0.009) and MC-HCV+MCS-HCV (p=0.014) groups. Multivariate logistic regression analysis identified cryoglobulinemia as an independent prognostic factor of non-response. The clinical-immunological response in MCS-HCV correlated with the virological one. All patients with SVR also experienced a sustained clinical response, either complete or partial. In the majority of SVR patients all MCS symptoms persistently disappeared (36 patients, 57%); in only 2 (3%) did definite MCS persist. All virological non-responders were also clinical non-responders, in spite of a transient improvement in some cases. No evolution to lymphoma was observed. For the first time we have evaluated both the effects of IFN-based therapy on HCV patients with or without MC, and with or without symptoms, and the long-term effects of viral eradication on MC. MC was shown to be a negative prognostic factor of virological response. HCV clearance led to persistent resolution or improvement of MC syndrome, strongly suggesting the need for a next generation of highly effective antiviral drugs

Role of MicroRNA Profile Modifications in Hepatitis C Virus-Related Mixed Cryoglobulinemia

Hepatitis C virus infection is closely related to lymphoproliferative disorders (LPDs), including mixed cryoglobulinemia (MC) and some lymphomas. Modification of the expression of specific microRNAs (miRNAs) has been associated with different autoimmune diseases and/or LPDs. No data exist about the modifications in miRNA expression in HCV-associated LPDs. The aim of this study was to analyze the expression levels of a panel of miRNAs previously associated with autoimmune/LPDs in a large population of HCV patients with and without MC or non-Hodgkin’s lymphoma (NHL), to identify potential markers of evolution of HCV infection. PBMC expression of miR-Let-7d, miR-16, miR-21, miR-26b, miR-146a and miR-155 was evaluated by real-time PCR in 167 HCV patients (75 with MC [MC-HCV], 11 with HCV-associated NHL [NHL-HCV], 81 without LPD [HCV]) and in 35 healthy subjects (HS). A significant increase in miR-21 (p<0.001), miR-16 (p<0.01) and miR-155 (p<0.01) expression was detected in PBMCs from only NHL patients whereas a significant decrease in miR-26b was detected in both MC and NHL subjects (p<0.01) when compared to HS and HCV groups. A restoration of miR-26b levels was observed in the post-treatment PBMCs of 35 HCV-MC patients experiencing complete virological and clinical response following antiviral therapy. This study, for the first time, shows that specific microRNAs in PBMC from HCV patients who developed MC and/or NHL are modulated differently. The specific, reversible downregulation of miR-26b strongly suggests the key role it plays in the pathogenesis of HCV-related LPDs and its usefulness as a biomarker of the evolution of HCV infection to these disorders

Solve-RD: systematic pan-European data sharing and collaborative analysis to solve rare diseases.

For the first time in Europe hundreds of rare disease (RD) experts team up to actively share and jointly analyse existing patient's data. Solve-RD is a Horizon 2020-supported EU flagship project bringing together >300 clinicians, scientists, and patient representatives of 51 sites from 15 countries. Solve-RD is built upon a core group of four European Reference Networks (ERNs; ERN-ITHACA, ERN-RND, ERN-Euro NMD, ERN-GENTURIS) which annually see more than 270,000 RD patients with respective pathologies. The main ambition is to solve unsolved rare diseases for which a molecular cause is not yet known. This is achieved through an innovative clinical research environment that introduces novel ways to organise expertise and data. Two major approaches are being pursued (i) massive data re-analysis of >19,000 unsolved rare disease patients and (ii) novel combined -omics approaches. The minimum requirement to be eligible for the analysis activities is an inconclusive exome that can be shared with controlled access. The first preliminary data re-analysis has already diagnosed 255 cases form 8393 exomes/genome datasets. This unprecedented degree of collaboration focused on sharing of data and expertise shall identify many new disease genes and enable diagnosis of many so far undiagnosed patients from all over Europe