Treatment of HCV-related mantle-cell lymphoma with ribavirin and pegylated interferon Alfa

Extrahepatic manifestations of HCV where do we stand?

Hepatitis C virus (HCV) infection has been associated as up 40-70% of patients with extrahepatic manifestations (EHM) and 36 different syndromes. These could be attributed to the fact that HCV is lymphotropic, particularly B lymphotropic, and not merely hepatotropic, and could trigger immunological alterations indirectly by exerting a chronic stimulus on the immune system with production of immunoglobulins having rheumatoid activity forming immune complexes and production of cryoglobulins. Cryoglobulinemoa plays a pivotal role in producing most EHM of HCV such as vasculitis, glomerulonephritis, arthritis and neuropathies. Less frequently; while less frequently, the direct viral cytopathic effect could lead to EHMs independent of cryoglobulinemia. The mainstay of treatment of EMH has been antivirals, since interferon era to direct-acting drugs era, with no differences between the two eras, despite the better virological response. Longer evaluation of virological response and clinical investigation with longer follow-ups are necessary.

Chronic Hepatitis C: Acute Exacerbation and Alanine Aminotransferase Flare

The hepatitis C virus (HCV) causes acute and chronic hepatitis, cirrhosis, and hepatocellular carcinoma, as well as extrahepatic manifestations such as malignant lymphoma. Currently, direct-acting antiviral agents (DAAs) against HCV infection can lead to a sustained virological response (SVR) in almost all HCV-infected patients. In this review article, we discuss acute exacerbation and alanine aminotransferase (ALT) flare in patients with chronic HCV infection. Although acute liver failure caused by HCV infection is rare, careful attention should be paid to the cases with ALT elevation during the natural course of chronic HCV infection. HCV genotype 2 infection, the use of rituximab, and a higher dose of corticosteroid are factors associated with HCV acute exacerbation and ALT flare. Treatment regimens for cancer have been interrupted or changed due to ALT flare due to HCV infection in some patients undergoing chemotherapy for cancer. The pathogenesis of HCV acute exacerbation and ALT flare could involve cellular as well as humoral immune responses. In the DAA era, the earlier introduction of DAAs may prevent chronic HCV-infected patients with acute exacerbation and ALT flare from developing into a more severe form, although DAAs may not be effective for all of them.

Second malignant neoplasms in lymphomas, secondary lymphomas and lymphomas in metabolic disorders/diseases

With inconsistent findings, evidence has been obtained in recent years that metabolic disorders are closely associated with the development of lymphomas. Studies and multiple analyses have been published also indicating that some solid tumor survivors develop a secondary lymphoma, whereas some lymphoma survivors subsequently develop a second malignant neoplasm (SMN), particularly solid tumors. An interaction between the multiple etiologic factors such as genetic factors and late effects of cancer therapy may play an important role contributing to the carcinogenesis in patients with metabolic diseases or with a primary cancer. In this review, we summarize the current knowledge of the multiple etiologic factors for lymphomagenesis, focusing on the SMN in lymphoma, secondary lymphomas in primary cancers, and the lymphomas associated to metabolic disorders/diseases, which have been received less attention previously. Further, we also review the data of coexistence of lymphomas and hepatocellular carcinoma (HCC) in patients with infection of hepatitis C virus and hepatitis B virus.

Hepatitis C virus and non-Hodgkin’s lymphomas: Meta-analysis of epidemiology data and therapy options

Hepatitis C virus (HCV) is a global health problem affecting a large fraction of the world’s population: This virus is able to determine both hepatic and extrahepatic diseases. Mixed cryoglobulinemia, a B-cell “benign” lymphoproliferative disorders, represents the most closely related as well as the most investigated HCV-related extrahepatic disorder. Since this virus is able to determine extrahepatic [non-Hodgkin’s lymphoma (NHL)] as well as hepatic malignancies (hepatocellular carcinoma), HCV has been included among human cancer viruses. The most common histological types of HCV-associated NHL are the marginal zone, the lymphoplasmacytic and diffuse large cell lymphomas. The role of the HCV in the pathogenesis of the B-cell lymphoproliferative disorders is confirmed also by the responsiveness of the NHL to antiviral therapy. The purpose of this review is to provide an overview of the recent literature and a meta analysis of the epidemiology data, to explain the role of HCV in the development of NHL’s lymphoma. Furthermore, the possibility to treat these HCV-related NHL with the antiviral therapy or with other therapeutic options, like chemotherapy, is also discussed.

microRNA levels in paraffin-embedded indolent B-cell non-Hodgkin lymphoma tissues from patients chronically infected with hepatitis B or C virus

Background

Epidemiological evidence links Hepatitis B Virus (HBV) and Hepatitis C Virus (HCV) to B-cell non-Hodgkin lymphoma (B-NHL). These B-NHLs, particularly those associated with HCV, may represent a distinct sub-group with peculiar molecular features, including peculiar expression of microRNAs (miRs).

The aim of the present study was to search for miRs whose level in indolent B-NHL tissues could be associated with HBV or HCV infection.

Methods

Fourteen formalin fixed paraffin embedded (FFPE) tissues from HBV+, HCV+ and HBV-/HCV- indolent B-NHL patients were analyzed for levels of 34 selected miRs by quantitative Real-Time PCR. Reactive lymph nodes (RLNs) from HBV-/HCV- patients were included as non-tumor control. Statistical analysis of output data included Pearson and Spearman correlation and Mann-Whitney test and were carried out by the STATA software.

Results

MiR-92a was decreased exclusively in HBV-/HCV- B-NHLs, while miR-30b was increased in HBV+ and HCV+ samples, though only the HCV+ achieved full statistical significance. Analysis of a small subset of B-NHLs belonging to the same histological subtype (Nodal Marginal Zone Lymphoma) highlighted three miRs associated with HCV infection (miR-223, miR-29a and miR-29b) and confirmed decreased level of miR-92a in HBV-/HCV- samples also when considering this restricted B-NHL group.

Conclusions

Although caution is needed due to the limited number of analyzed samples, overall the results suggest that differences at the miR expression level exist between indolent B-NHLs developed in patients with or without HBV or HCV infection. The identification of three further miRs associated with HCV by analyzing histologically homogeneous samples suggests that variations of miR levels possibly associated with HBV or HCV may be obscured by the tissue-specific variability of miR level associated with the different histological subtypes of B-NHL. Thus, the identification of further miRs will require, in addition to an increased sample size, the comparison of B-NHL tissues with the same histological classification.

Hepatitis C-associated B-cell non-Hodgkin lymphomas. Epidemiology, molecular signature and clinical management

There is ample epidemiologic evidence for an association of chronic hepatitis C virus (HCV) infection with B-cell non-Hodgkin lymphoma (B-NHL). B-NHL subtypes most frequently associated with HCV are marginal zone lymphoma and diffuse large B-cell lymphoma. The most convincing evidence for a causal relationship between HCV infection and lymphoma development is the observation of B-NHL regression after HCV eradication by antiviral therapy (AVT). In fact, for indolent HCV-associated B-NHL, first-line AVT instead of standard immune-chemotherapy might be considered. Molecular mechanisms of HCV-NHL development are still poorly understood. Three general theories have emerged to understand the HCV-induced lymphomagenesis: (1) continuous external stimulation of lymphocyte receptors by viral antigens and consecutive proliferation; (2) HCV replication in B cells with oncogenic effect mediated by intracellular viral proteins; (3) permanent B-cell damage, e.g., mutation of tumor suppressor genes, caused by a transiently intracellular virus ("hit and run" theory). This review systematically summarizes the data on epidemiology, interventional studies, and molecular mechanisms of HCV-associated B-NHL.

Indolent B-cell lymphomas associated with HCV infection: clinical and virological features and role of antiviral therapy

The association between hepatitis C virus (HCV) infection and B-cell non-Hodgkin's lymphomas (NHL) has been demonstrated by epidemiological studies, in particular in highly endemic geographical areas such as Italy, Japan, and southern parts of United States. In these countries, together with diffuse large B-cell lymphomas, marginal zone lymphomas are the histotypes most frequently associated with HCV infection; in Italy around 20–30% cases of marginal zone lymphomas are HCV positive. Recently, antiviral treatment with interferon with or without ribavirin has been proved to be effective in the treatment of HCV-positive patients affected by indolent lymphoma, prevalently of marginal zone origin. An increasing number of experiences confirmed the validity of this approach in marginal zone lymphomas and in other indolent NHL subtypes like lymphoplasmacytic lymphoma. Across different studies, overall response rate was approximately 75%. Hematological responses resulted significantly associated with the eradication of the virus. This is the strongest evidence of a causative link between HCV and lymphomas. The aim of this paper is to illustrate the relationship between HCV infection and different subtypes of indolent B-cell lymphomas and to systematically summarize the data from the therapeutic studies that reported the use of antiviral treatment as hematological therapy in patients with HCV-associated indolent lymphomas.

Lymphomas and leukemias due to infectious organisms

World-wide, approximately 25% of all human malignancies are caused by infectious organisms, including approximately 10% of cancers occurring in resource rich areas of the world. While some of these disorders are more likely to be seen in patients with underlying immunodeficiency, this is not a requisite for development of malignancy, and most patients, in fact, are not immune-suppressed at the time of diagnosis. In considering hematologic malignancies, several organisms have been implicated in disease etiology. These organisms include Human Herpesvirus 8 (HHV8/KSHV), which is linked to primary effusion lymphoma and to multicentric Castleman s disease, as well as to development of Kaposi's sarcoma; Epstein Barr Virus (EBV) which has been associated with Burkitt lymphoma and nasal T cell lymphoma, among others; Human T lymphotrophic virus type I (HTLV 1), which is associated with Adult T cell leukemia/lymphoma (ATLL); Hepatitis C virus, associated with splenic marginal and other lymphomas; and Helicobacter pylori, associated with gastric MALT lymphoma. The presentation will focus on the latter three disorders, describing pathogenesis of disease, clinical manifestations and therapeutic options.

Pathogenetic mechanisms of hepatitis C virus-induced B-cell lymphomagenesis

Hepatitis C virus (HCV) infection is probably the most common chronic viral infection and affects an estimated 180 million people worldwide, accounting for 3% of the global population. Although the liver is considered to be the primary target, extrahepatic manifestations are well recognized among patients with chronic HCV infection. Epidemiological studies have clearly demonstrated a correlation between chronic HCV infection and occurrence of B-cell non-Hodgkin's lymphomas (B-NHL). The clinical evidence that antiviral therapy has a significant role in the treatment at least of some HCV-associated lymphoproliferative disorders, especially indolent B-NHL, further supports the existence of an etiopathogenetic link. However, the mechanisms exploited by HCV to induce B-cell lymphoproliferation have so far not completely clarified. It is conceivable that different biological mechanisms, namely, chronic antigen stimulation, high-affinity interaction between HCV-E2 protein and its cellular receptors, direct HCV infection of B-cells, and "hit and run" transforming events, may be combined themselves and cooperate in a multifactorial model of HCV-associated lymphomagenesis.

Viral hit and run-oncogenesis: genetic and epigenetic scenarios

It is well documented that viral genomes either inserted into the cellular DNA or co-replicating with it in episomal form can be lost from neoplastic cells. Therefore, "hit and run"-mechanisms have been a topic of longstanding interest in tumor virology. The basic idea is that the transient acquisition of a complete or incomplete viral genome may be sufficient to induce malignant conversion of host cells in vivo, resulting in neoplastic development. After eliciting a heritable change in the gene expression pattern of the host cell (initiation), the genomes of tumor viruses may be completely lost, i.e. in a hit and run-scenario they are not necessary for the maintenance of the malignant state. The expression of viral oncoproteins and RNAs may interfere not only with regulators of cell proliferation, but also with DNA repair mechanisms. DNA recombinogenic activities induced by tumor viruses or activated by other mechanisms may contribute to the secondary loss of viral genomes from neoplastic cells. Viral oncoproteins can also cause epigenetic dysregulation, thereby reprogramming cellular gene expression in a heritable manner. Thus, we expect that epigenetic scenarios of viral hit and run-tumorigenesis may facilitate new, innovative experiments and clinical studies in spite of the fact that the regular presence of a suspected human tumor virus in an early phase of neoplastic development and its subsequent regular loss have not been demonstrated yet. We propose that virus-specific "epigenetic signatures", i.e. alterations of the host cell epigenome, especially altered DNA methylation patterns, may help to identify viral hit and run-oncogenic events, even after the complete loss of tumor viruses from neoplastic cells.

Hepatitis C virus infection and lymphoma

Apart from its well known role as an etiological agent for non-A and non-B viral hepatitis, there is growing evidence that hepatitis C virus is associated to B-cell non-Hodgkin lymphoma. The association between HCV and lymphoproliferative disorders has been recently postulated based on epidemiological data, biological studies and clinical observations. Although various subtypes of lymphomas appear to be associated to HCV, diffuse large B-cell lymphoma, small lymphocytic lymphoma/chronic lymphocytic leukemia and marginal zone lymphoma appeared to be particularly represented among HCV-positive patients. The causative role of HCV in those disorders has been further supported by the response to antiviral therapy. Despite a better understanding of pathophysiological processes at stake leading from HCV infection to overt lymphoma, many issues still need to be further elucidated. Although HCV has been demonstrated to directly infect peripheral blood mononuclear cells both in vitro and, in some cases, in vivo, a strong body of evidence rather supports the hypothesis of an indirect transformation mechanism by which sustained antigenic stimulation leads from oligoclonal to monoclonal expansion and sometimes to lymphoma, probably through secondary oncogenic events. Here, we review epidemiological and biological studies, as well as clinical data on antiviral therapy, linking HCV-infection to B-cell non-Hodgkin lymphoma.

Hepatitis C virus and disrupted interferon signaling promote lymphoproliferation via type II CD95 and interleukins

BACKGROUND & AIMS

The molecular mechanisms of lymphoproliferation associated with the disruption of interferon (IFN) signaling and chronic hepatitis C virus (HCV) infection are poorly understood. Lymphomas are extrahepatic manifestations of HCV infection; we sought to clarify the molecular mechanisms of these processes.

METHODS

We established interferon regulatory factor-1-null (irf-1(-/-)) mice with inducible and persistent expression of HCV structural proteins (irf-1/CN2 mice). All the mice (n = 900) were observed for at least 600 days after Cre/loxP switching. Histologic analyses, as well as analyses of lymphoproliferation, sensitivity to Fas-induced apoptosis, colony formation, and cytokine production, were performed. Proteins associated with these processes were also assessed.

RESULTS

Irf-1/CN2 mice had extremely high incidences of lymphomas and lymphoproliferative disorders and displayed increased mortality. Disruption of irf-1 reduced the sensitivity to Fas-induced apoptosis and decreased the levels of caspases-3/7 and caspase-9 messenger RNA species and enzymatic activities. Furthermore, the irf-1/CN2 mice showed decreased activation of caspases-3/7 and caspase-9 and increased levels of interleukin (IL)-2, IL-10, and Bcl-2, as well as increased Bcl-2 expression, which promoted oncogenic transformation of lymphocytes. IL-2 and IL-10 were induced by the HCV core protein in splenocytes.

CONCLUSIONS

Disruption of IFN signaling resulted in development of lymphoma, indicating that differential signaling occurs in lymphocytes compared with liver. This mouse model, in which HCV expression and disruption of IFN signaling synergize to promote lymphoproliferation, will be an important tool for the development of therapeutic agents that target the lymphoproliferative pathway.

Hepatitis C virus infection induced vasculitis

Cryoglobulinemia are immune complexes that may induce systemic cryoglobulinemic vasculitis, a small-vessel vasculitis involving the skin, the joints, the peripheral nerve system, and the kidneys. During the last 15 years, progresses have been done after the discovery of the hepatitis C virus, the main cause of cryoglobulins. Main factors associated with cryoglobulin production are female gender, alcohol intake above 50 g/day, extensive liver fibrosis, and steatosis. Symptomatic cryoglobulins (i.e., vasculitis) are associated with older age, longer duration of infection, and main characteristics of cryoglobulin (type II, IgM kappa, high serum levels). The physiopathology is complex, and it involves humoral immunity, B- and T-cellular immunity but not the virus itself. Peg-Interféron alpha Ribavirine combination leads to a virological and clinical response of the vasculitis in about 70% of patients. In nonresponders, recent open series suggested the efficacy of Rituximab with a good response in up to 80% of patients but a relapse in 42% after 7 months after the last infusion. For future prospects and projects, new therapeutic strategies include a combination of best antiviral treatment with Peg-Interferon plus Ribavirin and Rituximab. Multicenter controlled trials are mandatory.

Borrelia infection and risk of non-Hodgkin lymphoma

Reports of the presence of Borrelia burgdorferi DNA in malignant lymphomas have raised the hypothesis that infection with B. burgdorferi may be causally related to non-Hodgkin lymphoma (NHL) development. We conducted a Danish-Swedish case-control study including 3055 NHL patients and 3187 population controls. History of tick bite or Borrelia infection was ascertained through structured telephone interviews and through enzyme-linked immunosorbent assay serum analyses for antibodies against B. burgdorferi in a subset of 1579 patients and 1358 controls. Statistical associations with risk of NHL, including histologic subtypes, were assessed by logistic regression. Overall risk of NHL was not associated with self-reported history of tick bite (odds ratio [OR] = 1.0; 95% confidence interval: 0.9-1.1), Borrelia infection (OR = 1.3 [0.96-1.8]) or the presence of anti-Borrelia antibodies (OR = 1.3 [0.9-2.0]). However, in analyses of NHL subtypes, self-reported history of B. burgdorferi infection (OR = 2.5 [1.2-5.1]) and seropositivity for anti-Borrelia antibodies (OR = 3.6 [1.8-7.4]) were both associated with risk of mantle cell lymphoma. Notably, this specific association was also observed in persons who did not recall Borrelia infection yet tested positive for anti-Borrelia antibodies (OR = 4.2 [2.0-8.9]). Our observations suggest a previously unreported association between B. burgdorferi infection and risk of mantle cell lymphoma.

Hepatitis C virus (HCV)-induced immunoglobulin hypermutation reduces the affinity and neutralizing activities of antibodies against HCV envelope protein

Hepatitis C virus (HCV) often causes persistent infection despite the presence of neutralizing antibodies against the virus in the sera of hepatitis C patients. HCV infects both hepatocytes and B cells through the binding of its envelope glycoprotein E2 to CD81, the putative viral receptor. Previously, we have shown that E2-CD81 interaction induces hypermutation of heavy-chain immunoglobulin (V(H)) in B cells. We hypothesize that if HCV infects antibody-producing B cells, the resultant hypermutation of V(H) may lower the affinity and specificity of the HCV-specific antibodies, enabling HCV to escape from immune surveillance. To test this hypothesis, we infected human hybridoma clones producing either neutralizing or non-neutralizing anti-E2 or anti-E1 antibodies with a lymphotropic HCV (SB strain). All of the hybridoma clones, except for a neutralizing antibody-producing hybridoma, could be infected with HCV and support virus replication for at least 8 weeks after infection. The V(H) sequences in the infected hybridomas had a significantly higher mutation frequency than those in the uninfected hybridomas, with mutations concentrating in complementarity-determining region 3. These mutations lowered the antibody affinity against the targeting protein and also lowered the virus-neutralizing activity of anti-E2 antibodies. Furthermore, antibody-mediated complement-dependent cytotoxicity with the antibodies secreted from the HCV-infected hybridomas was impaired. These results suggest that HCV infection could cause some anti-HCV-antibody-producing hybridoma B cells to make less-protective antibodies.

Treatment of hepatitis C-associated mixed cryoglobulinemia vasculitis

PURPOSE OF REVIEW

Hepatitis C virus infection is the main cause of mixed cryoglobulinemia vasculitis. The disease expression of mixed cryoglobulinemia vasculitis is variable, ranging from mild clinical symptoms (purpura, arthralgia) to fulminant life-threatening complications (glomerulonephritis, widespread vasculitis). Treatment of hepatitis C virus-mixed cryoglobulinemia vasculitis may target either the viral trigger (hepatitis C virus) or the downstream B-cell arm of autoimmunity. This review focuses on recent advances in our understanding of the treatment of hepatitis C virus-mixed cryoglobulinemia vasculitis.

RECENT FINDINGS

Aggressive antiviral therapy with Peg-IFNalpha and ribavirin should be considered as induction therapy for hepatitis C virus-mixed cryoglobulinemia vasculitis with mild to moderate disease severity and activity. In patients presenting with severe disease, an induction phase of immunosuppression is often necessary while awaiting the generally slow response to antiviral treatments. Combination therapy with rituximab and Peg-IFNalpha plus ribavirin appears logical as it may target both the viral trigger (hepatitis C virus) and cryoglobulin-producing B-cells.

SUMMARY

Antiviral therapy and rituximab are the main therapeutic options in hepatitis C virus-mixed cryoglobulinemia vasculitis. Further studies are needed to better define the therapeutic strategy.

Hepatitis C infection and risk of malignant lymphoma

The association between hepatitis C virus (HCV) infection and risk of malignant lymphoma remains controversial, perhaps due to small-sized studies and low prevalence of HCV in the general population. On the basis of a large Danish-Swedish population-based case-control study, 2,819 lymphoma patients and 1,856 controls of second-generation Danish-Swedish origin were screened for HCV infection using an enzyme-linked immunosorbent assay and a confirming recombinant immunoblot assay (RIBA) test. Positive samples were tested with real-time PCR for the presence of HCV RNA. The association between HCV infection and risk of malignant lymphoma was assessed by logistic regression. When intermediate RIBA test results were interpreted as positive, anti-HCV antibody positivity was associated with a nonsignificant increased risk of non-Hodgkin lymphoma (NHL) overall (odds ratio (OR) = 2.2; 95% confidence interval (CI) 0.9-5.3; n = 20 cases), of B-cell lymphomas combined (OR = 2.4 [1.0-5.8]; n = 20) and of lymphoplasmacytic lymphoma (OR = 5.2 [1.0-26.4]; n = 2). No patients with T-cell or Hodgkin lymphoma were HCV-positive. A more conservative definition of HCV positivity (disregarding intermediate RIBA results) resulted in an OR = 1.6 (0.3-8.5; n = 5) for NHL overall. When the definition was further restricted to require HCV RNA positivity, OR was 1.7 (0.2-16.2; n = 3) for NHL overall. Our findings from a population with a low prevalence of HCV suggest a positive association between HCV and risk of NHL, in particular of B-cell origin.

Association of cells with natural killer (NK) and NKT immunophenotype with incident cancers in HIV-infected women

Evidence indicates that immunosupression is associated with the development of certain cancers. The pathogenesis of HIV disease includes an alteration in innate immunity, mediated through NK and NKT cells. The evaluation of innate immune status in HIV patients prior to cancer diagnosis may identify the specific immunological events preceding the development of malignant disease. We evaluated the association between immunophenotypically defined NK, NKT, and CD8(+) cell percentages and incident malignancies in 1817 HIV(+) women in the Women's Interagency HIV Study (WIHS) who were followed for a median of 7.5 years. A total of 52 incident cancers of 20 different sites were identified. Compared to cancer-free women, cancer cases were older (p < 0.01), more likely to be anti-HCV(+) (p = 0.02), and had higher baseline median HIV RNA levels than controls. The CD8(+), NK, and NKT percents at baseline were not related to cancer risk. However, when time-dependent values for NKT cells were used, higher levels of NKT cells were associated with a reduced risk of cancer (adjusted hazard ratio = 0.67, 95% CI = 0.50, 0.89 per NKT percentage point). In addition to the loss of CD4(+) lymphocytes and an increased risk of opportunistic infections, HCV coinfected individuals may also experience alterations in innate immunity, including reduced NKT and NK cell number and possibly their function. In time-dependent analyses, increased numbers of NKT cells were associated with a reduced risk of cancer. HIV-induced innate immune dysfunction may contribute to the eventual emergence of cancer in the setting of existing coinfections and altered immunosurveillance.

Rituximab in mixed cryoglobulinemia: increased experience and perspectives

Type II mixed cryoglobulinemia syndrome (MCsn) is a systemic vasculitis mainly linked to immune complex deposition in several organs and to hepatitis C virus (HCV) infection. Therapeutic strategies can target either the viral trigger HCV if present, or pathogenic events downstream the triggering infection, e.g, the proliferating B-cells directly. Antiviral therapy should be considered as first-line treatment in many HCV-positive patients. However, it may prove ineffective, contraindicated, or poorly tolerated. On the other hand, the other available treatments (such as cytotoxic agents, plasma exchange and steroids) may lead to life-threatening complications and may be difficult to manage in the long term. Given the good safety profile in lymphomas, rituximab (RTX) has been used off-label for numerous patients suffering from a variety of autoimmune diseases, including rheumatoid arthritis, systemic lupus erythematosus, dermatomyositis/ polymyositis, and anti-neutrophil cytoplasmic antibody (ANCA)-positive vasculitis. Efficacy and safety of RTX in MCsn and in particular in MCsn-related glomerulonephritis was recently described. Based on these results, a multicentre, controlled, randomised, clinical trial is now ongoing to compare RTX versus the best available treatments in some severe MCsn manifestations (i.e. skin ulcers, sensory and/or motor neuropathy and active glomerulonephritis).

Splenic lymphoma with villous lymphocytes, mixed cryoglobulinemia and HCV infection: deciphering the role of HCV in B-cell lymphomagenesis

Chronic hepatitis C virus (HCV) infection is associated with mixed cryoglobulinemia (MC) which can be viewed as a low-grade non-malignant B-cell lymphoproliferation. HCV is also associated with overt B-cell lymphomas but the direct causal relationship has remained elusive. The finding that HCV-associated splenic lymphomas with villous lymphocytes (SLVL), a subset of splenic marginal zone lymphomas, is constantly associated with MC and responds to antiviral therapy, and furthermore that the viral load strongly correlates with the tumor burden, lends support to the hypothesis that HCV is associated with antigen-driven B-cell transformation in a mechanism reminiscent of Helicobacter pylori-associated gastric MALT lymphoma. Moreover, the finding that HCV-positive large B-cell lymphomas appear to be transformed from low-grade B-cell lymphomas and that cryoglobulinemia is an independent risk factor for lymphoma in HCV-infected patients add support to this hypothesis. However, HCV-associated antigen-driven lymphomagenesis may not be the sole mechanism by which the virus could induce lymphomas, and a direct transformation of B-cells may be at play in some cases. HCV is among the growing list of pathogens associated with the development of lymphomas. Antiviral therapy should be considered as first-line therapy in low-grade B-cell and possibly large-cell lymphomas associated with HCV, especially in the presence of MC.

Cryoglobulinemia

Cryoglobulinemia refers to the presence in serum of immunoglobulins that precipitate at a cold temperature. Type I cryoglobulins are single monoclonal immunoglobulins usually associated with haematological disorders. Types II and III are mixed cryoglobulins, composed of monoclonal or polyclonal IgM respectively, having rheumatoid factor activity that bind to polyclonal immunoglobulins. Mixed cryoglobulinemia (MC) syndrome is a consequence of immune-complex mediated vasculitis and is characterized by a typical clinical triad: purpura, weakness, arthralgias; many organs particularly kidney and peripheral nervous system may be involved. MC may be associated with infectious and systemic disorders and since 1990 studies have demonstrated that hepatitis C virus (HCV) may be considered the principal trigger of the disease. The relation between MC and HCV infection shows new insights in the interpretation of the link between viral infection, autoimmune phenomena and lymphoproliferative disorders evolution. In fact, the virus chronically stimulates B-cell polyclonal proliferation from which a monoclonal population may emerge. In symptomatic patients with HCV related MC therapeutic strategy should include an attempt at viral eradication. Antiviral therapy may also be effective in determining the regression of B-cell lymphoproliferative disorder. Rituximab could represent a safe and effective alternative to standard immunosuppression and exerts selective B-cell control.

HCV-NS3 and IgG-Fc crossreactive IgM in patients with type II mixed cryoglobulinemia and B-cell clonal proliferations

We demonstrate that in three cases of MC (two with immunocytoma), the IgM-RF+ component of their cryoprecipitated represents the circulating counterpart of the B-cell receptor (BCR) of the monoclonal overexpanded B-cell population. These IgMs were isolated and used to demonstrate a crossreactivity against both hepatitis C virus (HCV) NS3 antigen and the Fc portion of IgG. Epitopes were identified in a fraction of exemplary samples by using epitope excision approach (NS(31250-1334) and IgG Fc(345-355)). The same phenomenon of crossreactivity has been shown to occur in vivo after immunization of a mouse with the NS3(1251-1270) peptide. To verify if the same reaction was also present in MC samples characterized by an oligo/polyclonal B-cell proliferation, IgM crossreactivity was tested in 14 additional samples. Five out of the 14 were reactive against HCV NS3 and 11 out of 14 were reactive against IgG-Fc peptide. The data support the role of HCV NS3 antigen in a subset of patients with MC, whereas the high frequency of the IgG-Fc epitope suggests that these B cells originate from precursors strongly selected for auto-IgG specificity. We suggest that engagement of specific BCRs by NS3 (or NS3-immunocomplex) antigen could explain the prevalence of IgM cryoglobulins in these patients.

Maligne Lymphome in der Leber

Primary hepatic lymphomas represent rare neoplasms, which are partly observed in association with chronic viral hepatitis, immunosuppression and autoimmune diseases. In contrast, secondary hepatic lymphomas are much more frequent and represent disseminated disease. Lymphomas involving the liver include, with decreasing frequency, diffuse large B-cell lymphoma, small lymphocytic lymphoma, Hodgkin's lymphoma, peripheral T-cell lymphoma, follicular lymphoma and extranodal marginal zone B-cell lymphoma. Many B-cell lymphomas in the liver reveal a characteristic infiltration pattern allowing a rapid and cost-effective diagnosis based on focused immunohistochemical analyses. In contrast, most T-cell lymphomas show a more diverse morphology, which is sometimes difficult to differentiate from a reactive condition. Therefore, additional molecular analyses are frequently necessary. The differential diagnosis includes hepatitis and inflammatory bile duct diseases, undifferentiated carcinoma, inflammatory myofibroblastic tumor as well as histiocytic and dendritic cell neoplasms.

Extrahepatic manifestations in patients with chronic hepatitis C virus infection

PURPOSE OF REVIEW

Chronic hepatitis C virus infection often has autoimmune clinical and analytic features. This review analyzes recent data on the close association of chronic hepatitis C virus infection with autoimmune and lymphoproliferative processes.

RECENT FINDINGS

Hepatitis C virus infection has been associated with both organ-specific (thyroiditis, diabetes) and systemic autoimmune diseases. Experimental, virologic, and clinical evidence has demonstrated a close association between hepatitis C virus infection and Sjögren syndrome, with hepatitis C virus-associated Sjögren syndrome being indistinguishable in most cases from the primary form. With respect to rheumatoid arthritis, patients with hepatitis C virus-related polyarthritis and positive rheumatoid factor may fulfill the classification criteria for rheumatoid arthritis. Hepatitis C virus has also been associated with an atypical presentation of antiphospholipid syndrome, as well as with the development of sarcoidosis. A higher prevalence of hematologic processes in patients with hepatitis C virus infection has recently been reported, including cytopenias and lymphoproliferative disorders. Recent data are available on the use of new immunosuppressive and biologic agents (mainly mycophenolate mofetil, anti-tumor necrosis factor agents, and rituximab) in patients with hepatitis C virus infection and autoimmune or lymphoproliferative manifestations.

SUMMARY

There is increasing evidence of a close association of hepatitis C virus infection with autoimmune and hematologic processes. The sialotropism of hepatitis C virus may explain the close association with Sjögren syndrome, and its lymphotropism links the virus to cryoglobulinemia, autoimmune cytopenias, and lymphoma. The substantial overlap between cryoglobulinemic features and the classification criteria for some systemic autoimmune diseases (systemic lupus erythematosus, rheumatoid arthritis, and polyarteritis nodosa) make the differentiation between mimicking and coexistence difficult.

Systemic autoimmune diseases co-existing with chronic hepatitis C virus infection (the HISPAMEC Registry): patterns of clinical and immunological expression in 180 cases

OBJECTIVES

To describe the clinical and immunologic characteristics of a large series of patients with systemic autoimmune diseases (SAD) associated with chronic hepatitis C virus (HCV) infection.

METHODS

We analysed 180 patients diagnosed with SAD and chronic HCV infection seen consecutively at our centres during the last 10 years. The clinical and immunological patterns of disease expression were compared with 180 SAD-matched patients without chronic HCV infection.

RESULTS

A total of 180 HCV patients fulfilled the classification criteria for the following SAD: Sjogren's syndrome (n = 77), systemic lupus erythematosus (n = 43), rheumatoid arthritis (n = 14), antiphospholipid syndrome (n = 14), polyarteritis nodosa (n = 8) and other SAD (n = 24). One hundred and thirty (72%) patients were female and 50 (28%) male, with a mean age at SAD diagnosis of 50 years. The main immunologic features were antinuclear antibodies in 69% of patients, cryoglobulinaemia in 62%, hypocomplementaemia in 56% and rheumatoid factor (RF) in 56%. Compared with the SAD-matched HCV-negative group, SAD-HCV patients presented a lower prevalence of females (P = 0.016), an older age at SAD diagnosis (P = 0.039) and a higher prevalence of vasculitis (P < 0.001) and neoplasia (P < 0.001). Immunologically, SAD-HCV patients presented a lower prevalence of antinuclear (P = 0.036), anti-extractable nuclear antigen (P = 0.038) and anti-DNA (P = 0.005) antibodies, and a higher frequency of RF (P = 0.003), hypocomplementaemia (P < 0.001) and cryoglobulins (P < 0.001).

CONCLUSIONS

In comparison with an SAD-matched HCV-negative population, SAD-HCV patients were older and more likely to be male, with a higher frequency of vasculitis, cryoglobulinaemia and neoplasia. This complex pattern of disease expression is generated by a chronic viral infection that induces both liver and autoimmune disease.

Mantle cell lymphoma

PURPOSE OF REVIEW

Mantle cell lymphoma is the B-cell lymphoma with the worst prognosis. Until now, no standard treatment has resulted in cure. Improvements in understanding of the disease are needed to advance therapeutic efforts.

RECENT FINDINGS

Pathology and immunohistochemistry can identify the subset of patients with the worse prognosis. New data suggest that at least a subset of mantle cell lymphoma cases have undergone some form of antigene selection, and particular types of Ig gene rearrangement seem to give a better prognosis. The cell cycle, the ATM, gene and the nuclear factor kappaB pathways are the main targets of the genetic abnormalities occurring in mantle cell lymphoma: new genomic and expression data have been recently published. Unfortunately, this progress has not yet brought any major improvements in therapeutic approaches, which still remain highly unsatisfactory. Autologous and allogenic bone marrow transplantations appear to be the only current treatments that might improve the outcome of patients with PMCL. New additional treatment modalities are currently under investigation.

SUMMARY

This review summarizes all the most recent data published on the biology and treatment of mantle cell lymphoma.

Systematic review: regression of lymphoproliferative disorders after treatment for hepatitis C infection

AIM

To systematically review the experience of therapeutic studies where alpha-interferon with or without ribavirin was administered to patients with lymphoproliferative disorders, in order to evaluate whether eradication of hepatitis C virus may induce regression of lymphoproliferative disorders.

METHODS

We used bibliographical searches in electronic databases and in the Cochrane Library to determine our results.

RESULTS

Sixteen studies where an anti-viral regimen was administered to 65 hepatitis C virus-infected patients with lymphoproliferative disorders were identified. Complete remission of the lymphoproliferative disorder was achieved in 75% of the cases. In contrast, hepatitis C virus-negative subjects did not respond to interferon, indicating that the response in the hepatitis C virus-infected patients is not merely due to the antiproliferative effect of interferon. Remission after HCV eradication was maintained, provided that infection did not reappear. In hepatitis C virus-infected patients with non-Hodgkin's lymphoma treated with corticosteroids/chemotherapy liver function tests deterioration did not occur. The addition of interferon to standard chemotherapy may decrease hepatic side-effects of chemotherapy.

CONCLUSIONS

Although it is evident that larger therapeutical trials of anti-viral therapy are needed to determine the role of this strategy in hepatitis C virus-infected patients with lymphoproliferative disorders, encouraging data emerge from recent studies showing that interferon (plus ribavirin) is an attractive therapeutic option for some hepatitis C virus-related low-grade lymphomas.

Role of anti-hepatitis C virus (HCV) treatment in HCV-related, low-grade, B-cell, non-Hodgkin's lymphoma: a multicenter Italian experience

PURPOSE

Hepatitis C virus (HCV) is endemic in some areas of Northwestern Europe and the United States. HCV has been shown to play a role in the development of both hepatocellular carcinoma and B-cell non-Hodgkin's lymphoma (B-NHL). The biologic mechanisms underlying the lymphomagenic activity of the virus so far are under investigation. In this study, the role of antiviral (anti-HCV) treatment in B-NHL associated with HCV infection is evaluated.

PATIENTS AND METHODS

Thirteen patients with histologically proven low-grade B-NHL characterized by an indolent course (ie, doubling time no less than 1 year, no bulky disease) and carrying HCV infection were enrolled on the study. All patients underwent antiviral treatment alone with pegilated interferon and ribavirin. Response assessment took place at 6 and 12 months.

RESULTS

Of the twelve assessable patients, seven (58%) achieved complete response and two (16%) partial hematologic response at 14.1 +/- 9.7 months (range, 2 to 24 months, median follow-up, 14 months), while two had stable disease with only one patient experiencing progression of disease. Hematologic responses (complete and partial, 75%) were highly significantly associated to clearance or decrease in serum HCV viral load following treatment (P = .005). Virologic response was more likely to be seen in HCV genotype 2 (P = .035), while hematologic response did not correlate with the viral genotype. Treatment-related toxicity did not cause discontinuation of therapy in all but two patients, one of whom, however, achieved complete response.

CONCLUSION

This experience strongly provides a role for antiviral treatment in patients affected by HCV-related, low-grade, B-cell NHL.

Cryoglobulinemia

Mixed cryoglobulinemia (MC) type II is a disorder characterized by circulating cold-precipitable immune complexes composed of polyclonal immunoglobulin IgG and monoclonal IgM rheumatoid factor (RF). The systemic vasculitis which characterizes the disease is caused by the deposition of immune complexes on the walls of small vessels, and by the subsequent activation of the complement cascade. MC may be asymptomatic or lead to clinical manifestations characterized by a typical triad--purpura, arthralgia, and weakness--and in some cases by a more serious vasculitis with neurologic and renal involvement. In the vast majority (more than 90%) of patients, MC is associated with hepatitis C virus (HCV) infection, which is considered the triggering factor of the disease. The association between cryoglobulinemia and HCV infection, and the possible evolution to B-cell lymphomas usually after long-term follow-up, suggest the role of HCV infection both in the pathogenesis of MC and in lymphomagenesis. In fact, the virus chronically stimulates the polyclonal proliferation of B cells from which a monoclonal population may emerge. This paper also reviews the treatment strategies for MC syndrome, emphasizing the issue of the eradication of HCV, and the clinical and biological activity of rituximab for selective B-cell control.

Response to antiviral treatment in hepatitis C virus-associated marginal zone lymphomas

A link between chronic hepatitis C virus (HCV) infection and low-grade B-cell lymphomas has been suggested by epidemiological studies. Marginal zone lymphomas (MZLs) including splenic lymphomas with villous lymphocytes are among the most frequently reported subgroups in the setting of chronic HCV infection. In this study, we examined the effect of antiviral treatment in eight patients with HCV-associated MZL. We found that five out of eight patients have responded to interferon alpha and ribavirin. In some cases, hematologic responses were correlated to virologic responses. In addition, we report a case of large granular lymphocyte leukemia occurring in association with MZL and HCV, and responding to interferon and ribavirin. We suggest that there is an etiologic link between HCV and antigen-driven lymphoproliferative disorders.

Splenic lymphoma with villous lymphocytes, associated with type II cryoglobulinemia and HCV infection: a new entity?

Hepatitis C virus (HCV) has been associated with the development of B-cell non-Hodgkin lymphomas. We recently reported the regression of splenic lymphoma with villous lymphocytes (SLVL) in patients with HCV after antiviral treatment, demonstrating a direct role of HCV in lymphomagenesis. This study expands our previous results in 18 patients with chronic HCV and SLVL. Mixed cryoglobulinemia (MC) was present in all cases and was symptomatic in 13 (72%). All patients were treated with interferon alone or in association with ribavirin. Hematologic and virologic responses were correlated. Fourteen (78%) patients achieved a sustained complete hematologic response after clearance of HCV RNA. Two patients had a virologic partial response and achieved a complete hematologic response. Two virologic nonresponders achieved partial hematologic response. Regardless of the response, monoclonal immunoglobulin gene rearrangement persisted after treatment. This study underscores the role of HCV in the lymphomagenesis and the benefit of antiviral treatment for patients presenting with HCV-driven lymphoproliferations.