Hepatitis C virus (HCV) and lymphomagenesis

Hepatitis C virus-associated B-cell lymphomas: The importance of the new direct antiviral agent therapy

Hepatitis C virus (HCV) is a hepatotropic and lymphotropic virus, responsible for both chronic hepatitis and extra-hepatic manifestations. Multiple epidemiologic, clinical, biological, and molecular studies have suggested that HCV plays a causal role also in the development of several lymphoproliferative disorders, either benign, such as mixed cryoglobulinemia, or malignant, such as B-cell non-Hodgkin lymphomas (NHL). Chronic viral antigenic stimulation of B-lymphocytes plays a fundamental basic role from the onset of lymphoma to its final steps. In the past, several studies demonstrated that the association of pegylated interferon plus ribavirin was able to eradicate HCV, with subsequent regression of indolent B-cell low-grade NHL. Other studies have demonstrated that direct antiviral agents (DAAs) therapy have some efficacy in HCV-associated NHL, particularly in patients with low-grade NHL or marginal zone-lymphoma, but these results need to be confirmed in larger studies with longer follow-up. The response rate of antiviral therapy seems favorable also in high grade NHL when DAAs therapy is administered in combination with chemotherapy and therefore antiviral therapy should be considered as a first-line approach in HCV-related NHL.

SARS-CoV-2 and cancer: the intriguing and informative cross-talk

The COVID-19 pandemic caused by the SARS-CoV-2 virus has significantly disrupted and burdened the diagnostic workup and delivery of care, including transfusion, to cancer patients across the globe. Furthermore, cancer patients suffering from solid tumors or hematologic malignancies were more prone to the infection and had higher morbidity and mortality than the rest of the population. Major signaling pathways have been identified at the intersection of SARS-CoV-2 and cancer cells, often leading to tumor progression or alteration of the tumor response to therapy. The reactivation of oncogenic viruses has also been alluded to in the context and following COVID-19. Paradoxically, certain tumors responded better following the profound infection-induced immune modulation. Unveiling the mechanisms of the virus-tumor cell interactions will lead to a better understanding of the pathophysiology of both cancer progression and virus propagation. It would be challenging to monitor, through the different cancer registries, retrospectively, the response of patients who have been previously exposed to the virus in contrast to those who have not contracted the infection.

HCV-related lymphoproliferative disorders in the direct-acting antiviral era: From mixed cryoglobulinaemia to B-cell lymphoma

HCV has been shown to induce many B-cell lymphoproliferative disorders. B lymphocytes specialise in producing immunoglobulins and, during chronic HCV infection, they can cause manifestations ranging from polyclonal hypergammaglobulinaemia without clinical repercussions, through mixed cryoglobulinaemic vasculitis to B-cell non-Hodgkin lymphoma. This spectrum is supported by substantial epidemiological, pathophysiological and therapeutic data. Many, although not all, of the pathogenic pathways leading from one extreme to another have been decrypted. Chronic viral antigen stimulation of B lymphocytes has a central role until the final steps before overt malignancy. This has direct implications for treatment strategies, which always include the use of direct-acting antivirals sometimes alongside immunosuppressants. The role of direct-acting antivirals has been well established in patients with cryoglobulinaemia vasculitis. However, their positive impact on B-cell non-Hodgkin lymphoma needs to be confirmed in larger studies with longer follow-up.

Distinct clinical features and prognostic factors of hepatitis C virus-associated non-Hodgkin's lymphoma: a systematic review and meta-analysis

BACKGROUND

Increasing evidence suggests that hepatitis C virus (HCV) infection is associated with non-Hodgkin's lymphoma (NHL). However, no clear consensus has been reached about the clinical features and effective treatment of HCV-associated NHL patients. We therefore performed a systematic review and meta-analysis to explore the clinical characteristics and effectiveness of antiviral treatment or rituximab administration among NHL patients with HCV infection.

METHODS

Eight electronic databases, including PubMed, OVID, EMBASE, Cochrane Library, ClinicalTrials, WANFANG, CNKI, and VIP, were searched for eligible studies up to July 31, 2021. The hazard ratio (HR) or odds ratio (OR) corresponding to the 95% confidence interval (CI) was calculated to estimate the outcomes. Publication bias was assessed by Egger's and Begg's tests. Statistical analysis was performed with RevMan 5.4 software and Stata version 15.

RESULTS

There were 27 shortlisted articles out of a total of 13,368 NHL patients included in the current meta-analysis. Our results demonstrated that NHL patients with HCV infection had a significantly shorter overall survival (OS: HR 1.89; 95% CI 1.42-2.51, P < 0.0001) and progression-free survival (PFS: HR 1.58; 95% CI 1.26-1.98, P < 0.0001), a lower overall response rate (ORR: OR 0.58, 95% CI 0.46-0.73, P < 0.00001) and a higher incidence of hepatic dysfunction during chemotherapy (OR 5.96; 95% CI 2.61-13.62, P < 0.0001) than NHL patients without HCV infection. HCV-positive NHL patients exhibited an advanced disease stage, an elevated level of LDH, a high-intermediate and high IPI/FLIPI risk as well as a higher incidence of spleen and liver involvement. Moreover, antiviral treatment prolonged survival (OS: HR 0.38; 95% CI 0.24-0.60, P < 0.0001), reduced disease progression [PFS/DFS (disease-free survival): HR 0.63; 95% CI 0.46-0.86, P = 0.003] and reinforced the treatment response (ORR: OR 2.62; 95% CI 1.34-5.11, P = 0.005) among the HCV-infected NHL patients. Finally, rituximab administration was associated with a favourable OS, while liver cirrhosis and low levels of albumin predicted a poor OS for HCV-positive NHL patients.

CONCLUSIONS

The current study provided compelling evidence about an inferior prognosis and distinct clinical characteristics among HCV-associated NHL patients. Antiviral treatment and rituximab-containing regimens were shown to be efficacious in improving the clinical outcomes of NHL patients with HCV infection.

Incidence, Prognostic Factors and Survival Outcome in Patients With Primary Hepatic Lymphoma

Aim: The objective of our study was to investigate the epidemiologic characteristics, prognostic factors and survival in patients with primary hepatic lymphoma (PHL). Methods: PHL patients diagnosed between 1983 and 2015 were identified from the SEER database. The temporal trend in PHL incidence was assessed using joinpoint regression software. Overall survival(OS) and disease-specific survival (DSS) was evaluated using the Kaplan-Meier method and log-rank test. Univariate and multivariate Cox regression analysis was performed to identify the independent prognostic factors for OS and DSS. Nomograms to predict survival possibilities were constructed based on the identified independent prognostic factors. Results: A total of 1,182 patients were identified with PHL. The mean age was 61.7 ± 17.1 years with a male to female of 1.6:1. Diffuse large B-cell lymphoma (59.8%) was the most common histological subtype. The incidence of PHL steadily increasing by an annual percentage change (APC) of 2.6% (95% CI 2.0-3.2, P < 0.05). The 1-, 5-, and 10-year OS rates were 50.85, 39.6, and 30.4%, respectively, and the corresponding DSS rates were 55.3, 47.9, and 43.3%, respectively. Multivariate Cox regression analysis revealed that age, sex, race, marital status, histological subtype, surgery, and chemotherapy were independent prognostic factors for survival. Nomograms specifically for DLBCL were constructed to predict 1-, 5-, and 10-year OS and DSS possibility, respectively. The concordance index (C-index) and calibration plots showed the established nomograms had robust and accurate performance. Conclusion: PHL were rare but the incidence has been steadily increasing over the past four decades. Survival has improved in recent years. Surgery or chemotherapy could provide better OS and DSS. The established nomograms specifically for DLBCL were robust and accurate in predicting 1-, 5-, and 10-year OS and DSS.

Heterogeneity and coexistence of oncogenic mechanisms involved in HCV-associated B-cell lymphomas

The association of HCV-infection with B-lymphomas is supported by the regression of most indolent/low-grade lymphomas following anti-viral therapy. Studies on direct and indirect oncogenic mechanisms have elucidated the pathogenesis of HCV-associated B-lymphoma subtypes. These include B-lymphocyte proliferation and sustained clonal expansion by HCV-envelope protein stimulation of B-cell receptors, and prolonged HCV-infected B-cell growth by overexpression of an anti-apoptotic BCL-2 oncogene caused by the increased frequency of t(14;18) chromosomal translocations in follicular lymphomas. HCV has been implicated in lymphomagenesis by a "hit-and-run" mechanism, inducing enhanced mutation rate in immunoglobulins and anti-oncogenes favoring immune escape, due to permanent genetic damage by double-strand DNA-breaks. More direct oncogenic mechanisms have been identified in cytokines and chemokines in relation to NS3 and Core expression, particularly in diffuse large B-cell lymphoma. By reviewing genetic alterations and disrupted signaling pathways, we intend to highlight how mutually non-contrasting mechanisms cooperate with environmental factors toward progression of HCV-lymphoma.

Extrahepatic cancers are the leading cause of death in patients achieving hepatitis B virus control or hepatitis C virus eradication

Data on extrahepatic cancers (EHCs) in compensated viral cirrhosis are limited. The objective of the prospective multicenter Agence Nationale de Recherche sur le SIDA et les Hépatites virales CO12 CirVir cohort was to assess the occurrence of all clinical events in patients with compensated viral cirrhosis, including all types of cancer. Patients with the following inclusion criteria were enrolled in 35 French centers: (1) biopsy-proven hepatitis B virus (HBV) or hepatitis C virus (HCV) cirrhosis, (2) Child-Pugh A, or (3) absence of previous liver complications including primary liver cancer (PLC). Patients were followed up prospectively every 6 months. The standardized mortality ratio (SMR) was calculated according to age and gender using 5-year periods. The impact of sustained viral response (SVR) in HCV patients and maintained viral suppression in HBV patients were assessed using time-dependent analysis. A total of 1,671 patients were enrolled between 2006 and 2012 (median age, 54.9 years; men, 67.3%; HCV, 1,323; HBV, 317; HCV-HBV, 31). Metabolic features and excessive alcohol and tobacco consumption were recorded in 15.2%, 36.4%, and 56.4% of cases, respectively. After a median follow-up of 59.7 months, 227 PLCs were diagnosed (5-year cumulative incidence [CumI] 13.4%) and 93 patients developed EHC (14 patients with lymphoid or related tissue cancer and 79 with solid tissue cancer; 5-year EHC CumI, 5.9%). Compared to the general French population, patients were younger at cancer diagnosis, with significantly higher risk of EHC in HCV patients (SMR, 1.31; 95 confidence interval [CI], 1.04-1.64; P = 0.017) and after SVR (SMR = 1.57; 95% CI, 1.08-2.22; P = 0.013). EHC was the fourth leading cause of death in the whole cohort and the first in patients with viral control/eradication.

CONCLUSION

Compared to the general French population, HCV cirrhosis is associated with a higher risk of EHC and the first cause of death in patients with viral cirrhosis who achieve virological control/eradication. (Hepatology 2018).

Preferential association of hepatitis C virus with CD19+ B cells is mediated by complement system

Extrahepatic disease manifestations are common in chronic hepatitis C virus (HCV) infection. The mechanism of HCV-related lymphoproliferative disorders is not fully understood. Recent studies have found that HCV in peripheral blood mononuclear cells from chronically infected patients is mainly associated with cluster of differentiation 19-positive (CD19+ ) B cells. To further elucidate this preferential association of HCV with B cells, we used in vitro cultured virus and uninfected peripheral blood mononuclear cells from healthy blood donors to investigate the necessary serum components that activate the binding of HCV to B cells. First, we found that the active serum components were present not only in HCV carriers but also in HCV recovered patients and HCV-negative, healthy blood donors and that the serum components were heat-labile. Second, the preferential binding activity of HCV to B cells could be blocked by anti-complement C3 antibodies. In experiments with complement-depleted serum and purified complement proteins, we demonstrated that complement proteins C1, C2, and C3 were required to activate such binding activity. Complement protein C4 was partially involved in this process. Third, using antibodies against cell surface markers, we showed that the binding complex mainly involved CD21 (complement receptor 2), CD19, CD20, and CD81; CD35 (complement receptor 1) was involved but had lower binding activity. Fourth, both anti-CD21 and anti-CD35 antibodies could block the binding of patient-derived HCV to B cells. Fifth, complement also mediated HCV binding to Raji cells, a cultured B-cell line derived from Burkitt's lymphoma.

CONCLUSION

In chronic HCV infection, the preferential association of HCV with B cells is mediated by the complement system, mainly through complement receptor 2 (CD21), in conjunction with the CD19 and CD81 complex. (Hepatology 2016;64:1900-1910).

Hepatitis C and double-hit B cell lymphoma successfully treated by antiviral therapy

B cells lymphoma is one of the most challenging extra-hepatic manifestations of hepatitis C virus (HCV). Recently, a new kind of B-cell lymphoma, named double-hit B (DHL), was characterized with an aggressive clinical course whereas a potential association with HCV was not investigated. The new antiviral direct agents (DAAs) against HCV are effective and curative in the majority of HCV infections. We report the first case, to our knowledge, of DHL and HCV-infection successfully treated by new DAAs. According to our experience, a DHL must be suspected in case of HCV-related lymphoma, and an early diagnosis could direct towards a different hematological management because a worse prognosis might be expected. A possible effect of DAAs on DHL regression should be investigated, but eradicating HCV would avoid life-threatening reactivation of viral hepatitis during pharmacological immunosuppression in onco-haematological diseases.

[IGHV mutational statue in patients with splenic marginal zone lymphoma]

目的

研究脾边缘区淋巴瘤（SMZL）患者免疫球蛋白重链可变区（IGHV）基因突变状态及典型模式的分布情况，并与国外报道的数据进行对比，以探讨其差异。

方法

对40例SMZL患者资料进行回顾性分析。采用克隆测序法检测IGHV的VDJ序列并进行比对及聚类分析，明确是否存在B细胞受体的典型模式，分析IGHV突变患者与未突变患者的临床特征。

结果

40例患者中，IGHV突变者30例（75.0%），未突变者10例（25.0%），两者比例与国外报道相当。在V区基因，V2-70的使用频率高于国外报道（10.3％对0.8%，P=0.002），而V3-23明显减低（2.6％对18.0%，P=0.006）。在D区基因中，D2-21和D6-13均高于国外报道（17.9％对2.3%，12.8%对3.8%，P值分别为0.000、0.046）。40例患者中发现1对新的典型模式，同时SMZL特异性的V1-2基因使用频率也最高（25.6%）。与IGHV突变组相比，未突变组患者的IgG、IgA表达水平显著增高[10.70（5.28~15.50）g/L对12.90 (7.71~23.50) g/L，1.06（0.21~3.13) g/L对1.66 (0.81~2.93) g/L，P值分别为0.038、0.040）]，2例17p缺失患者的IGHV均呈未突变状态。与IGHV未突变组相比，突变组患者的无进展生存期显著延长（P=0.009），但总生存期差异无统计学意义（P=0.430）。

结论

在SMZL患者中，IGHV突变与未突变患者比例与国外报道相当，但V区和D区基因的使用频率仍存在差异，而且V1-2基因的使用呈现疾病特异性，同时发现1例新的典型模式。IGHV突变可降低患者的IgG、IgA表达水平。

Hepatitis C virus-associated B-cell non-Hodgkin's lymphomas: what do we know?

Epidemiological studies have shown an increased risk of developing B-cell lymphomas in patients with chronic hepatitis C virus (HCV) infection. There is, however, a great geographic variability and it remains unclear whether additional environmental and genetic factors are involved or whether the international discrepancies represent simply a consequence of the variable prevalence of HCV infection in different countries. Other confounding factors may affect the comparability of the different studies, including the method of HCV assessment, the selection of normal controls, the lymphoma classification used and the year of publication. The most convincing evidence for a causal relationship comes from the observation, mainly limited to some indolent subtypes, of B-cell lymphoma regressions after successful HCV eradication with antiviral treatment. Yet, the molecular mechanism of HCV-induced lymphomagenesis are mainly hypothetical. According to most plausible models, lymphoma growth is a consequence of continuous antigenic stimulation induced by the chronic viral infection. This review will summarize the current knowledge on HCV-associated lymphomas and their management.

Emerging role of infectious etiologies in the pathogenesis of marginal zone B-cell lymphomas

Extranodal marginal zone B-cell lymphomas of the mucosa-associated lymphoid tissue (MALT) arise from lymphoid populations that are induced by chronic inflammation in extranodal sites. The most frequently affected organ is the stomach, where MALT lymphoma is incontrovertibly associated with a chronic gastritis induced by a microbial pathogen, Helicobacter pylori. Gastric MALT lymphoma therefore represents a paradigm for evaluating inflammation-associated lymphomagenesis, which may lead to a deeper understanding of a possible etiologic association between other microorganisms and nongastric marginal zone lymphomas. Besides infectious etiology, chronic inflammation caused by autoimmune diseases, such as Sjögren syndrome or Hashimoto thyroiditis, can also carry a significant risk factor for the development of marginal zone lymphoma. In addition to the continuous antigenic drive, additional oncogenic events play a relevant role in lymphoma growth and progression to the point at which the lymphoproliferative process may eventually become independent of antigenic stimulation. Recent studies on MALT lymphomas have in fact demonstrated genetic alterations affecting the NF-κB) pathway, a major signaling pathway involved in many cancers. This review aims to present marginal zone lymphoma as an example of the close pathogenetic link between chronic inflammation and tumor development, with particular attention to the role of infectious agents and the integration of these observations into everyday clinical practice. See all articles in this CCR Focus section, "Paradigm Shifts in Lymphoma."

Hepatitis C virus-associated B-cell non-Hodgkin lymphomas

Epidemiological studies have demonstrated an increased risk of developing B-cell lymphomas in patients with chronic hepatitis C virus (HCV) infection. However, the strength of the association shows great geographic discrepancies, with higher relative risk in countries with high HCV prevalence. It remains unclear whether additional environmental and genetic factors are involved or if the international variability is simply a consequence of the variable infection prevalence. Therefore, a causal relationship remains controversial. Other confounding factors may affect the comparability of the different studies, including the method of HCV assessment, the selection of normal controls, the lymphoma classification used, and the year of publication. The most convincing proof is the observation, mainly limited to some indolent subtypes, of B-cell lymphoma regressions after HCV eradication with IFN and ribavirin. However, the molecular mechanisms of the HCV-induced lymphomagenesis are mainly hypothetical. According to the model considered to be most plausible, lymphoma growth is a consequence of the continuous antigenic stimulation of the B-cell immunologic response induced by the chronic viral infection. This review summarizes the current epidemiological and biological evidence of a role of HCV in lymphomagenesis, describing the putative mechanisms for a causative relationship. The clinical characteristics and management difficulties of the HCV-associated lymphomas are also discussed. HCV treatment with IFN cannot be given safely in concomitance with cytotoxic lymphoma treatment because of hematological and liver toxicity. However, novel and better tolerated antiviral regimens are under development and will hopefully make the treatment of both lymphoma and hepatitis easier in the future.

CD81 sequence and susceptibility to hepatitis C infection

Several cell surface molecules have hepatitis C virus (HCV) binding properties and may serve as receptors facilitating viral entry into cells. The large extracellular loop (LEL) of CD81 has been shown to bind the HCV envelope protein E2 with several critical residues for the CD81-HCV-E2 interaction. It was hypothesised that variation in the CD81 LEL sequence may modify susceptibility to HCV infection. HCV RNA negative patients with spontaneous viral clearance (RNA -ve); HCV RNA positive cases, who are affected chronically (RNA +ve); and patients at high risk of HCV infection, exposed but uninfected patients (EU) were studied. Genomic DNA was extracted from whole blood samples and four exons of the CD81 LEL gene were amplified by PCR and sequenced. The cDNA derived from CD81 (≈700 bp) was sequenced following RNA extraction from peripheral blood mononuclear cells. Patients, who are RNA positive, RNA negative, and exposed uninfected were sequenced for four DNA sections (A, B, C, and D). Sixty-two (43M:19F) patients, from all the patient cohorts, were sequenced and compared for the C section alone (which encompasses the important binding region of the molecule for envelope protein) including 21 (14M:7F) HCV RNA negative, 15 (10M:5F) HCV RNA positive and 26 (20M:6F) exposed uninfected and no sequence differences were observed. The entire CD81 sequence from cDNA was obtained in 23 cases-11 RNA -ve, 5 RNA +ve and 7 EU. In 7 of the 23 cases, the nucleotides were confirmed with the genomic sequence (4 RNA -ve and 3 EU cases). No sequence variation was found in any of the patients studied by either method, including gene sections encoding the residues most important for CD81-HCV E2 binding. The LEL of CD81 is a molecule that is highly conserved. No differences in nucleotide sequence influencing susceptibility to, or outcome of HCV infection or evidence of methylation of the gene were found.

Lymphoproliferative disorders in individuals with chronic hepatitis B and C in the Turkish population

The aims of this cohort study were to evaluate the association of malignant lymphoproliferative disorders in patients with chronic viral hepatitis and to compare the results with those in individuals with non-alcoholic fatty liver disease. A total of 3,873 patients with chronic liver disease who were seen consecutively in the Liver Disease Outpatient Clinic between January 2001 and July 2007 were assessed retrospectively. The frequency of malignant lymphoproliferative disorders including non-Hodgkin's lymphoma, Hodgkin's lymphoma, and chronic lymphocytic leukemia in these patients was investigated. Of the total, 1,999 patients had chronic hepatitis B infection (male/female: 1,226/773, mean age: 45.1 ± 13.2 years), 978 had chronic hepatitis C infection (male/female: 437/541, mean age: 53.8 ± 13.7 years), and the remaining 896 had non-alcoholic fatty liver disease (male/female: 450/446, mean age: 50.8 ± 11.2 years). A malignant lymphoproliferative disorder was identified in 13 patients (male/female: 9/4, mean age: 52.8 ± 16.8 years) with chronic viral hepatitis, while no case of malignant lymphoproliferative disorder was identified in individuals with non-alcoholic fatty liver disease (P = 0.048). Among the patients with malignant lymphoproliferative disorders, seven had chronic hepatitis B infection and six had chronic hepatitis C infection; 11 had non-Hodgkin's lymphoma and two had chronic lymphocytic leukemia. All non-Hodgkin's lymphoma cases were B-cell lymphoma. Based on the data obtained in this investigation, the association with malignant lymphoproliferative disorders in chronic viral hepatitis seems to be high as compared to that occurring in individuals with non-alcoholic fatty liver disease.

Epidemiologic overview of malignant lymphoma

Malignant lymphoma encompasses a wide variety of distinct disease entities. It is generally more common in developed countries and less common in developing countries. The East Asia region has one of the lowest incidence rates of malignant lymphoma. The incidence of malignant lymphoma around the world has been increasing at a rate of 3-4% over the last 4 decades, while some stabilization has been observed in developed countries in recent years. The reasons behind this lymphoma epidemic are poorly understood, although improving diagnostic accuracy, the recent AIDS epidemic, an aging world population and the increasing adoption of cancer-causing behaviors are suggested as contributing factors. Etiologies of malignant lymphoma include infectious agents, immunodeficiency, autoimmune disease, exposure to certain organic chemicals, and pharmaceuticals. The distribution of many subtypes exhibit marked geographic variations. Compared to the West, T/natural killer (NK) cell lymphomas (T/NK-cell lymphoma) and extranodal marginal zone lymphoma of mucosa-associated lymphoid tissue (MALT lymphoma) are relatively more common, whereas other B-cell lymphomas, particularly follicular lymphoma and chronic lymphocytic leukemia/small lymphocytic lymphoma, are less common in Asia. Some subtypes of T/NK-cell lymphomas defined by Epstein-Barr virus association are predominantly Asian diseases, if not exclusively so. Both ethnic and environmental factors play roles in such diversity. In this review, we discuss the geographic distribution and etiology of malignant lymphoma, as well as the trend.

Hepatitis C reactivation in patients who have diffuse large B-cell lymphoma treated with rituximab: a case report and review of literature

BACKGROUND

Whether to interrupt or to continue induction therapy for lymphoma when hepatitis C virus (HCV) reactivation occurs during therapy with rituximab and chemotherapy remains a controversial question. There is limited evidence-based literature to help guide the management of patients with lymphoma in the setting of HCV reactivation. To address this issue we report an illustrative case and review the prevalence of non-Hodgkin lymphoma (NHL) in HCV-infected patients; the role of HCV in lymphomagenesis; the role of antiviral therapy in the management of HCV-associated lymphomas; as well as comparing the outcomes for NHL patients with and without HCV infection.

CASE REPORT

A patient diagnosed with diffuse large B-cell lymphoma was treated with rituximab and chemotherapy with the patient achieving a complete remission, but treatment was complicated by asymptomatic HCV reactivation. Because conflicting data exist regarding management of such cases, the criteria for discontinuing chemotherapy, in the event of escalation in HCV replication in an asymptomatic patient, remain unclear.

CONCLUSION

Patients with HCV have increased prevalence of marginal zone lymphoma, diffuse large B-cell lymphoma, and lymphoplasmacytic lymphoma. Whether HCV has a role in the lymphomagenesis is still uncertain, and limited to conjecture. The question whether to treat HCV-related lymphomas with antiviral therapy is debatable and not well-supported. Without initial liver dysfunction, HCV-infected patients can experience a similar outcome compared to their HCV-negative counterparts when treated with standard chemotherapy/immunotherapy despite differences in the presentation of the disease.

[Hematologic malignant complications after transplantation]

Post-transplant hemopathies are a serious complication of organ transplantation. They include several entities: non-hodgkin lymphoma, Hodgkin disease and myeloma. The pathophysiology, clinical and histological features, treatment and evolution of these diseases are different, but share some similarities. Among factors involved in lymphomagenesis, the role of Epstein Barr virus and immunosuppression are central. EBV primo-infection or reactivation together with a deep depression of T-cell immunity is at particular risk of lymphoma development. The clinical expression and outcome of lymphomas are varied. Assays for EBV replication quantification have been developed leading to immunosuppression decreasing and antiviral therapy when the replication increases. Treatment of post-transplant lymphoproliferations consists mainly in immunotherapy and chemotherapy. Hodgkin disease and myeloma are rare after transplantation; their management is close to the one of immunocompetent patients. The recurrence of myeloma, amyloidosis or light chain deposition disease seems frequent after transplantation and only patients with disappearance of monoclonal component should be proposed for transplantation. On the opposite, the risk of recurrence appears lower for Hodgkin disease; therefore the transplantation of patients with a history of Hodgkin disease looks possible.

Hepatitis C virus protects human B lymphocytes from Fas-mediated apoptosis via E2-CD81 engagement

HCV infection is often associated with B-cell regulatory control disturbance and delayed appearance of neutralizing antibodies. CD81 is a cellular receptor for HCV and can bind to HCV envelope protein 2 (E2). CD81 also participates to form a B cell costimulatory complex. To investigate whether HCV influences B cell activation and immune function through E2 -CD81 engagement, here, human Burkitt's lymphoma cell line Raji cells and primary human B lymphocytes (PHB) were treated with HCV E2 protein and cell culture produced HCV particles (HCVcc), and then the related cell phenotypes were assayed. The results showed that both E2 and HCVcc triggered phosphorylation of IκBα, enhanced the expression of anti-apoptosis Bcl-2 family proteins, and protected Raji cells and PHB cells from Fas-mediated death. In addition, both E2 protein and HCVcc increased the expression of costimulatory molecules CD80, CD86 and CD81 itself, and decreased the expression of complement receptor CD21. The effects were dependent on E2-CD81 interaction on the cell surface, since CD81-silenced Raji cells did not respond to both treatments; and an E2 mutant that lose the CD81 binding activity, could not trigger the responses of both Raji cells and PHB cells. The effects were not associated with HCV replication in cells, for HCV pseudoparticle (HCVpp) and HCVcc failed to infect Raji cells. Hence, E2-CD81 engagement may contribute to HCV-associated B cell lymphoproliferative disorders and insufficient neutralizing antibody production.

T-cell receptor-driven lymphomagenesis in mice derived from a reprogrammed T cell

The conversion of mature somatic cells into pluripotent stem cells, both by nuclear transfer and transduction with specific "reprogramming" genes, represents a major advance in regenerative medicine. Pluripotent stem cell lines can now be generated from an individual's own cells, facilitating the generation of immunologically acceptable stem cell-based therapeutics. Many cell types can undergo nuclear reprogramming, leading to the question of whether the identity of the reprogrammed cell of origin has a biological consequence. Peripheral blood, containing a mixture of T, B, NK, and myeloid cell types, represents one potential source of reprogrammable cells. In this study, we describe the unique case of mice derived from a reprogrammed T cell. These mice have prerearranged T-cell receptor (TCR) genes in all cells. Surprisingly, ≈50% of mice with prerearranged TCR genes develop spontaneous T cell lymphomas, which originate in the thymus. The lymphomas arise from developing T cells, and contain activated Notch1, similar to most human and mouse T-cell acute lymphoblastic lymphomas. Furthermore, lymphomagenesis requires the expression of both prerearranged TCRα and TCRβ genes, indicating a critical role for TCR signaling. Furthermore, inhibitors of multiple branches of TCR signaling suppress lymphoma growth, implicating TCR signaling as an essential component in lymphoma proliferation. The lymphomagenesis in mice derived from a reprogrammed T cell demonstrates the deleterious consequences of misregulation of the TCR rearrangement and signaling pathways and illustrates one case of cellular reprogramming where the identity of the cell of origin has profound consequences.

Hepatitis C virus and autoimmunity

Hepatitis C virus infection is associated with several extrahepatic manifestations. About 60% of patients infected with HCV develop at least one extrahepatic manifestation. The majority of these diseases seem to be triggered through autoimmune mechanisms, such as autoantibody production, autoreactive T cells and complex autoimmune mechanisms leading to systemic autoimmune disorders. In this review we categorize these diseases into three groups according to the main pathogenetic process involved, in particular B-cell-mediated, T-cell-mediated and complex autoimmune systemic diseases.

Causes and Predictive Factors of Mortality in a Cohort of Patients with Hepatitis C Virus-related Cryoglobulinemic Vasculitis Treated with Antiviral Therapy

Objective.

Hepatitis C virus (HCV)-associated mixed cryoglobulinemia (MC) vasculitis is an autoimmune disorder with significant morbidity and mortality. Renal involvement was associated with an increased mortality, and was the most common cause of death; these data were obtained before effective antiviral treatment was available. We studied causes of death and predictive factors in patients with HCV-associated MC vasculitis treated with antivirals.

Methods.

Case histories of 85 patients with HCV-associated MC vasculitis treated in a single center between 1990 and 2006 were retrospectively reviewed. Prognostic factors affecting mortality were studied by comparing 23 patients who died with 62 survivors, using the Cox model regression analysis.

Results.

The most common cause of death was infection, accounting for 34.7%, followed by endstage liver disease in 30.4% (including 4 patients with hepatocellular carcinoma), and cardiovascular disease in 17.4% of patients. Endstage renal disease accounted for only 8.7% of deaths, as did central nervous system vasculitis and nonhepatic malignancy. Increased mortality was strongly associated with immunosuppressive treatment [hazard ratio (HR) 6.51, 95% CI 2.75–15.37], cutaneous ulcers (HR 5.37, 95% CI 1.79–16.14), and renal insufficiency (HR 3.25, 95% CI 1.37–7.72). A 2 log10 decrease in HCV viral load at month 3 after starting antiviral treatment was associated with decreased mortality (HR 0.39, 95% CI 0.16–0.95).

Conclusion.

While renal involvement is still associated with poorer prognosis, infectious processes are now the most common cause of death in HCV cryoglobulinemia vasculitis. Immunosuppressive treatment is associated with an increased risk of death, independently from disease severity. Response to antiviral treatment is associated with significantly reduced mortality risk.

Enhanced RIG-I expression is mediated by interferon regulatory factor-2 in peripheral blood B cells from hepatitis C virus-infected patients

Chronic hepatitis C patients carry the risk of developing into B-cell non-Hodgkin's lymphoma (B-NHL). To clarify the mechanisms underlying this association, we first investigated the molecular markers of B cells from hepatitis C virus (HCV)-infected patients. CD19-positive cells were isolated as B cells from the peripheral blood mononuclear cells of patients infected with the hepatitis C virus and IFN-related gene expression was analyzed. We found that RIG-I and IRF-2 expression were up-regulated in CD19-positive cells from the infected patients. In vitro luciferase reporter analysis using human cell lines indicated that IRF-2 activates the human RIG-I promoter. IRF-2 expression levels were enhanced by HCV cDNA transfection in Huh7 cells. In addition, we observed much less induction in the interferon stimulated gene 15 (ISG15) after Sendai virus (SenV) stimulation of CD19-positive cells from infected patients versus healthy controls, thereby suggesting an impairment of RIG-I downstream signaling in HCV-infected patients. Hence, we found that the failure of the anti-viral response with enhanced IRF-2 oncogenic protein expression in blood B cells from HCV-infected patients. Our results provide important information to better understand the role of IRFs in the cause of HCV chronic infection.

CD81 protein is expressed at high levels in normal germinal center B cells and in subtypes of human lymphomas

CD81 is a tetraspanin cell surface protein that regulates CD19 expression in B lymphocytes and enables hepatitis C virus infection of human cells. Immunohistologic analysis in normal hematopoietic tissue showed strong staining for CD81 in normal germinal center B cells, a cell type in which its increased expression has not been previously recognized. High-dimensional flow cytometry analysis of normal hematopoietic tissue confirmed that among B- and T-cell subsets, germinal center B cells showed the highest level of CD81 expression. In more than 800 neoplastic tissue samples, its expression was also found in most non-Hodgkin lymphomas. Staining for CD81 was rarely seen in multiple myeloma, Hodgkin lymphoma, or myeloid leukemia. In hierarchical cluster analysis of diffuse large B-cell lymphoma, staining for CD81 was most similar to other germinal center B cell-associated markers, particularly LMO2. By flow cytometry, CD81 was expressed in diffuse large B-cell lymphoma cells independent of the presence or absence of CD10, another germinal center B-cell marker. The detection of CD81 in routine biopsy samples and its differential expression in lymphoma subtypes, particularly diffuse large B-cell lymphoma, warrant further study to assess CD81 expression and its role in the risk stratification of patients with diffuse large B-cell lymphoma.

Subcutaneous 'lipoma-like' B-cell lymphoma associated with HCV infection: a new presentation of primary extranodal marginal zone B-cell lymphoma of MALT

BACKGROUND

Hepatitis C virus (HCV) infection has been linked to lymphoproliferative disorders. Marginal zone B-cell lymphoma (MZL) represents one of the most frequent lymphoma subtypes associated with HCV infection. We describe an unusual subset of HCV-associated MZL characterized by subcutaneous presentation.

MATERIALS AND METHODS

A series of 12 HCV-positive patients presenting with subcutaneous nodules that revealed lymphoma infiltration at biopsy. Molecular analysis of immunoglobulin heavy chain (IGH) gene rearrangement and FISH investigations for t(11;18)(q21;q21) and t(14;18)(q32;q21) were carried out in nine patients.

RESULTS

The 12 patients (median age 69.5 years), all with positive HCV serology, presented with single or multiple subcutaneous nodules resembling lipomas. Histologically the lesions showed lymphoid infiltrates, consistent with extranodal MZL of mucosa-associated lymphoid tissue (MALT). Functional IGH gene rearrangements were identified in nine tested patients, with somatic mutations in 82%, indicating a histogenesis from germinal center-experienced B cells. The t(11;18) was found in two of nine cases. Staging did not show any other lymphoma localization. In two patients, a response was achieved with antiviral treatment. Extracutaneous spread to MALT sites occurred in a case.

CONCLUSIONS

Our observations expand the spectrum of HCV-associated lymphomas to include a subset of extranodal MZL characterized by a novel primary 'lipoma-like' subcutaneous presentation and indolent clinical course.

Hepatitis C and lymphoproliferative disorders: from mixed cryoglobulinemia to non-Hodgkin's lymphoma

BACKGROUND & AIMS

Hepatitis C virus is associated with both mixed cryoglobulinemia and non-Hodgkin's lymphoma, particularly B-cell non-Hodgkin's Lymphoma. Although there are geographic discrepancies in the incidence and prevalence of hepatitis C virus-related lymphomas, large epidemiologic studies and meta-analyses confirm this relationship in both patients with and without mixed cryoglobulinemia. Other factors such as gene translocation, somatic hypermutation and direct infection may also play a role in the malignant transformation of B-cells.

METHODS

Recent advances in our understanding between the complex relationship between hepatitis C virus and its interactions with cell proteins on B-cell surface membranes has led to proposed mechanisms on how hepatitis C virus leads to chronic antigenic stimulation resulting in lymphoproliferation.

RESULTS

Hepatitis C virus is more weakly associated with T-cell lymphomas, Waldenstrom's macroglobulinemia and other monoclonal gammopathies. Remission of mixed cryoglobulinemia is strongly associated with reduction of hepatitis C virus viral load and recurrence of disease corresponds with viral relapse. Similarly, some studies have shown complete remissions of low grade lymphomas with sustained viral response after antiviral therapy for hepatitis C virus.

CONCLUSIONS

Further studies are needed to more clearly understand the pathogenesis and management of hepatitis C virus-related lymphoproliferative disorders.

Hepatitis C virus association with peripheral blood B lymphocytes potentiates viral infection of liver-derived hepatoma cells

Hepatitis C virus (HCV) primarily replicates within the liver, leading to hepatitis, fibrosis, and hepatocellular carcinoma. Infection is also associated with B-cell abnormalities, suggesting an association of the virus with B cells. The infectious JFH-1 strain of HCV can bind primary and immortalized B cells but fails to establish productive infection. However, B cell-associated virus readily infects hepatoma cells, showing an enhanced infectivity compared with extracellular virus. B cells express the viral receptors CD81, SR-BI, and the C-type lectins DC-SIGN and L-SIGN. Antibodies specific for SR-BI and DC-SIGN/L-SIGN reduced B-cell transinfection, supporting a role for these molecules in B-cell association with HCV. Stimulation of B cells with CD40 ligand and interleukin-4 promoted their ability to transinfect hepatoma cells. B cell-associated virus is resistant to trypsin proteolysis and HCV-specific neutralizing antibodies, consistent with particle internalization. HCV promoted the adhesion of primary B cells to Huh-7 hepatomas, providing a mechanism for B-cell retention in the infected liver. In summary, B cells may provide a vehicle for HCV to persist and transmit to the liver.

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.

Excellent prognosis and prevalence of HCV infection of primary hepatic and splenic non-Hodgkin's lymphoma

BACKGROUND

Primary Hepatic (PHL) and Primary Splenic (PSL) non-Hodgkin's Lymphoma are rare entities. Small series of PHL and PSL have been reported, suggesting a non-fortuitous association with Hepatitis C Virus (HCV) infection. The prognosis is believed to be dismal, with early recurrence and short survival.

PATIENTS

We retrospectively reviewed all PHL and PSL patients diagnosed at our institution between 1990 and 2005.

RESULTS

Twenty-five adult patients were identified, six with PHL and 19 with PSL. Twenty-four patients had a B-cell lymphoma, defined as Diffuse Large B-cell lymphoma in 18. The prevalence of HCV infection was 68% among PSL and 66% among PHL. Combination chemotherapy was the mainstay of treatment for PHL and PSL; all but one patient with PSL underwent splenectomy before chemotherapy. Complete remission was achieved in all the cases after frontline therapy; only four patients relapsed but responded to additional chemotherapy courses. Most patients presented with aggressive histological subtypes; 92% were alive at a median follow up of 79 months. HCV infection did not appear to influence the results of therapy.

CONCLUSION

Our study confirms the rarity of PHL and PSL, shows a high prevalence of HCV infection, and demonstrates that the outcome of patients with PHL and PSL may be favourable.

HCV non-structural protein 3 and HCV RNA genome in non-Hodgkin lymphoma and transition of the serum HCV RNA level: a retrospective analysis in one institution

There have been various reports on the association of hepatitis C virus (HCV) infection with B lymphocyte proliferative disorders, such as non-Hodgkin lymphoma (NHL). We experienced a case (Case 1) of anti-HCV antibody (HCV-Ab)-positive NHL in which HCV nonstructural protein 3 (NS3) expression was observed in lymphoma tissue at the time of recurrence and in which the serum HCV RNA level exhibited a transient increase prior to recurrence. We investigated the HCV RNA genome in lymphoma tissue in Case 1, and it could be detected at recurrence. We also investigated HCV NS3 protein expression in lymphoma tissue and changes in serum HCV RNA level during the clinical course in four other cases of HCV-Ab-positive NHL treated in our hospital. We examined lymphoma tissues for HCV NS3 protein expression in four of the five cases, but it was not identified except for in Case 1 at recurrence. In three cases with no recurrence, serum HCV RNA levels showed a tendency to decrease after completion of chemotherapy and became stable thereafter. Further studies are necessary to clarify the association between serum HCV RNA and the onset and exacerbation of NHL.

Clonal expansion of immunoglobulin M+CD27+ B cells in HCV-associated mixed cryoglobulinemia

Hepatitis C virus (HCV) is associated with B-cell lymphoproliferative disorders such as mixed cryoglobulinemia (MC) and B-cell non-Hodgkin lymphoma (B-NHL). The pathogenesis of these disorders remains unclear, and it has been proposed that HCV drives the pro-liferation of B cells. Here we demonstrate that certain HCV(+)MC(+) subjects have clonal expansions of immunoglobulin M (IgM)(+)kappa(+)IgD(low/-)CD21(low)CD27(+) B cells. Using RT-PCR to amplify Ig from these singly sorted cells, we show that these predominantly rheumatoid factor-encoding V(H)1-69/J(H)4 and V(kappa)3-20 gene segment-restricted cells have low to moderate levels of somatic hypermutations. Ig sequence analysis suggests that antigen selection drives the generation of mutated clones. These findings lend further support to the notion that specific antigenic stimulation leads to B-cell proliferation in HCV MC and that chronic B-cell stimulation may set the stage for malignant transformation and the development of B-NHL. The finding that these hypermutated, marginal zone-like IgM(+)CD27(+) B cells are clonally expanded in certain subjects with MC offers insight into mechanisms of HCV-associated MC and B-cell malignancy. This study was registered at www.clinicaltrials.gov as NCT00219999.

Therapeutic control of hepatitis C virus: the role of neutralizing monoclonal antibodies

Liver failure associated with hepatitis C virus (HCV) accounts for a substantial portion of liver transplantation. Although current therapy helps some patients with chronic HCV infection, adverse side effects and a high relapse rate are major problems. These problems are compounded in liver transplant recipients as reinfection occurs shortly after transplantation. One approach to control reinfection is the combined use of specific antivirals together with HCV-specific antibodies. Indeed, a number of human and mouse monoclonal antibodies to conformational and linear epitopes on HCV envelope proteins are potential candidates, since they have high virus neutralization potency and are directed to epitopes conserved across diverse HCV genotypes. However, a greater understanding of the factors contributing to virus escape and the role of lipoproteins in masking virion surface domains involved in virus entry will be required to help define those protective determinants most likely to give broad protection. An approach to immune escape is potentially caused by viral infection of immune cells leading to the induction hypermutation of the immunoglobulin gene in B cells. These effects may contribute to HCV persistence and B cell lymphoproliferative diseases.

Hepatitis C virus and lymphoma

Hepatitis C virus (HCV) is well known for its aetiological role in chronic non-A, non-B viral hepatitis, liver cirrhosis and hepatocellular carcinoma; in addition, the virus has also been implicated in a number of extra-hepatic "autoimmune" disease manifestations. A causative association between HCV and non-Hodgkin lymphoma (NHL) was postulated relatively recently and has been the subject of intense investigation, as well as some debate. On the strength of epidemiological data, emerging biological investigations and clinical observations, HCV appears to be involved in the pathogenesis of at least a proportion of patients with NHL. Morphologically, HCV-associated lymphomas represent a variety of histological subtypes including marginal zone lymphoma (splenic, nodal and extranodal), small lymphocytic lymphoma/chronic lymphocytic leukaemia, lymphoplasmacytic lymphoma and diffuse large B-cell lymphoma. Remarkably, some HCV-associated NHL appears to be highly responsive to antiviral therapy, providing some clinical evidence for this relationship, as well as the prospect for novel therapeutic intervention.

Simultaneous hepatic relapse of non-Hodgkin's lymphoma and hepatocellular carcinoma in a patient with hepatitis C virus-related cirrhosis

We report a 66-year-old man with hepatitis C virus (HCV)-related cirrhosis and simultaneous hepatic relapse of non-Hodgkin's lymphoma (NHL) and of hepatocellular carcinoma (HCC). Although the liver is frequently involved by NHL, hepatic colocalization of NHL and HCC is rarely detected by imaging techniques. HCV has been suggested to be lymphotrophic as well as hepatotrophic, and therefore has attracted speculation about a causative role in some cases of lymphoma. The patient had a past history of cutaneous diffuse large B cell lymphoma (DLBCL) in concurrence with HCC 32 months previously. Complete remission (CR) had been maintained for both diseases until February 2004, when ultrasonography and computed tomography (CT) showed multiple liver tumors. Two of these, appearing hyperattenuating in the arterial phase of contrast-enhanced CT, were diagnosed histopathologically as HCC, and treated with radiofrequency ablation. The other tumors, hypoattenuating in the portal phase CT, were diagnosed histopathologically as DLBCL, and treated with cyclophosphamide, tetrahydropyranyl-Adriamycin, vincristine and prednisolone (THP-COP) in combination with rituximab. CR was achieved for both DLBCL and HCC. Given the previously demonstrated immune system tropism and perturbation by HCV, the virus might have contributed to the occurrence of the NHL as well as the HCC.

Functionality of the immune system in patients with chronic hepatitis C: trial by superinfections and vaccinations

Viral infections, specifically chronic, markedly influence the host response to subsequent infections and vaccinations. Does this apply to chronic hepatitis C (CHC)? The review considers this question with implications for the immune status and functionality of the immune system of a chronically HCV-infected host. The data collected here indicate that CHC may increase the risk of viral superinfections and modify their course by immunocompromising the host. Patients with CHC do not lose the 'memory' of previous infections and vaccinations but, apparently, have problems with building such immunity anew, as illustrated by their impaired response to hepatitis A and B vaccinations. This underlines the necessity of extra protection of CHC patients against blood-borne diseases, hepatitis A, possibly also varicella, influenza, tetanus, and diphtheria - immunity to which, in the Western population, appears to falter. Such immune protection has to be adapted to selective impairments of immune response characteristic to CHC. Some approaches to this are reviewed here and more need to be elaborated. Special attention has to be given to CHC patients who do not respond to common vaccines; further studies in this field are of great interest.

CD81, a cell cycle regulator, is a novel target for histone deacetylase inhibition in glioma cells

Recent advances in cancer cell biology have focused on histone deacetylase inhibitors (HDACi's) because they target pathways critical to the development and progression of disease. In particular, HDACi's can induce expression of epigenetically silenced genes that promote growth arrest, differentiation and cell death. In glioma cells, one such repressed gene is the tetraspanin CD81, which regulates cytostasis in various cell lines and in astrocytes, the major cellular component of gliomas. Our studies show that HDACi's, trichostatin and sodium butyrate, promote growth arrest and differentiation with negligible cell death in glioma cells and induce expression of CD81 and cyclin-dependent kinase inhibitor 1A (p21(CIP/WAF-1)), another regulator of cytostasis in astrocytes. Interference RNA knock-down of CD81 abrogates cytostasis promoted by HDAC inhibition indicating that HDACi-induced CD81 is responsible for growth arrest. Induction of CD81 expression through HDAC inhibition is a novel strategy to promote growth arrest in glioma cells.

Interleukin-29 uses a type 1 interferon-like program to promote antiviral responses in human hepatocytes

Interleukin-28A (IL-28A), IL-28B and IL-29 are a family of class II cytokines that stimulate antiviral responses through a heterodimeric receptor that is distinct from the type I interferon (IFN) receptor. To better understand how this newly described family of cytokines regulates the antiviral state, we compared various cellular responses elicited by IL-29 and IFN-alpha. Here we show that these cytokines stimulate similar patterns of signal transducer and activator of transcription 1 (STAT-1), -2, -3, and -5 phosphorylation and nearly identical patterns of gene expression when analyzed in two distinct cell types by microarray analysis. Interestingly, the IL-29 receptor is preferentially expressed on primary hepatocytes within normal liver and pegylated forms of IL-29 and IFN-alpha induced equivalent 2'5' oligoadenylate synthetase (OAS) and MX1 gene expression in this cell type. Pegylated IL-29 also produced a significant reduction in human hepatitis B and hepatitis C viral load in vitro and reduced the cytopathic effect caused by the fully replicating flavivirus, West Nile virus. In conclusion, IL-29 and IFN-alpha stimulate identical antiviral responses despite their utilization of different receptors. This fact, combined with significant receptor expression in hepatitis virus-infected livers, suggests that IL-29 may have therapeutic value against chronic viral hepatitis in human patients.

Cancer incidence in people with hepatitis B or C infection: a large community-based linkage study

BACKGROUND/AIMS

Risks of hepatocellular carcinoma (HCC) following hepatitis B and/or hepatitis C virus (HBV/HCV) infection are well known, those for other cancers are less well understood. The aim was to quantify the risk of cancers among persons diagnosed with HBV/HCV infections.

METHODS

The data from a cohort of 39109 HBV, 75834 HCV, and 2604 HBV/HCV co-infected persons notified to the State health department, 1990-2002, were probabilistically linked to the Cancer Registry and standardised incidence ratios (SIRs) for cancer were calculated.

RESULTS

The match rate for any cancer was 2.7%, 2.3% and 3.3% for HBV, HCV and HBV/HCV co-infected notifications. SIRs for HCC were 30.6 (95% CI 25.7-36.5), 22.7 (95% CI 19.1-26.5) and 30.3 (95% CI 13.6-67.5), respectively. Increased risk was detected for Burkitt's lymphoma and HBV (SIR 12.9, 95% CI 5.4-30.9) and immunoproliferative malignancies following HCV (SIR 5.6, 95% CI 1.8-17.5).

CONCLUSIONS

The risk of HCC in the infected cohort was 20-30 times greater than in the uninfected population with SIRs two to three times greater than those for the other HBV/HCV infection associated cancers. The modest though significant risk of immunoproliferative malignancies associated with HCV infection is consistent with recent findings.

Is there an association between ocular adnexal lymphoma and infection with Chlamydia psittaci?

Various subsets of extranodal marginal zone lymphomas of mucosa-associated lymphoid tissues (MALT lymphomas) have been associated with infectious organisms. Most notable of these is the association of gastric MALT lymphomas with Helicobacter pylori infection. In a recent publication Ferreri et al. [Ferreri AJ, Guidoboni M, Ponzoni M, De Conciliis C, Dell'Oro S, Fleischhauer K, et al. Evidence for an association between Chlamydia psittaci and ocular adnexal lymphomas. J Natl Cancer Inst 2004;96:586-94] reported the presence of C. psittaci DNA in 80% of 40 ocular adnexal lymphomas. Similar to the gastric MALT lymphoma data, a subset of these patients responded well to antibiotic treatment. We analyzed a set of ocular adnexal lymphomas and benign (non-neoplastic) lesions for evidence of C. psittaci DNA in patients from New York State. No evidence of C. psittaci DNA was seen in seven MALT-type ocular adnexal lymphomas, four non-MALT ocular lymphomas, one Langerhans histiocytosis, and five reactive lymphoproliferations. We eliminated several possible reasons that would cause our study to fail to find C. psittaci DNA, including the presence of PCR inhibitors, inadequate template DNA, and sequence diversity in the target region in C. psittaci. The positive data were based primarily on patients from Italy, while our study involved only patients living in the Northeastern United States. This would suggest possible geographic differences in the etiology of ocular adnexal lymphomas.

Myeloma, Hodgkin disease, and lymphoid leukemia after renal transplantation: characteristics, risk factors and prognosis

BACKGROUND

Hodgkin disease and myeloma were recently included in the classification of posttransplant lymphoproliferative disorder (PTLD). However, because their incidence is low, not much is known about their particular features.

METHODS

The incidence, characteristics, risk, and prognostic factors of myeloma, Hodgkin disease, and lymphoid leukemia using the United States Renal Data System from 1991 to 2000 among 66,159 Medicare patients were analyzed.

RESULTS

In all, 1,169 recipients developed a lymphoid disease: 823 (1.2%) non-Hodgkin's lymphomas (NHL), 160 (0.24%) myelomas, 60 (0.1%) Hodgkin lymphomas, and 126 (0.2%) lymphoid leukemias. Older age was associated with an increased risk of myeloma and leukemia. The incidence of hepatitis C virus infection was higher in recipients with myeloma (6.9 vs. 3.9%, P=0.05). Induction therapy was associated with a greater risk of myeloma and leukemia, but not Hodgkin disease. Azathioprine was associated with a lower risk of myeloma, and tacrolimus with a lower risk of Hodgkin disease. According to the type of malignancy, ten-year survival rates were significantly different: 42, 26, 55 and 39% respectively for NHL, myeloma, Hodgkin disease, and leukemia.

CONCLUSION

These results support specific features and risk factors related to the occurrence of each type of lymphoid-proliferation and suggest for the first time a possible association between hepatitis C virus and myeloma in kidney transplant recipients.

Non-Hodgkin's lymphoma involving the liver: clinical and therapeutic considerations

Primary hepatic non-Hodgkin's lymphoma (NHL) is a rare disease that presents unique diagnostic and therapeutic challenges. Secondary liver involvement by lymphoma is common and can complicate treatment decisions. A review of the published case reports and the few larger series suggests that primary hepatic NHL represents a heterogeneous mixture of disparate diseases rather than a single entity. Presentations vary from the incidental discovery of hepatic abnormalities in an otherwise asymptomatic patient to that of fulminant hepatic failure with rapid progression of encephalopathy to coma and death. The clinical, laboratory, and radiographic characteristics are nonspecific, which means the diagnosis is often not suspected until histopathologic examination of liver tissue. There appears to be a strong association between primary hepatic NHL and the hepatitis C virus. Hepatosplenic T-cell lymphoma has attained its own status as a unique disease, whereas case reports suggest that the spectrum of hepatic lymphoma includes many histologies. Involvement of the liver by lymphoma can compound the difficulty of pursuing aggressive chemotherapy in patients who have a life-threatening illness and impaired metabolism of the most effective drugs. Therapy should be tailored to the individual clinical situation, with consideration of the underlying histology and degree of hepatic insufficiency.