Cytokine signaling pathway polymorphisms and AIDS-related non-Hodgkin lymphoma risk in the multicenter AIDS cohort study

Update: The molecular spectrum of virus-associated high-grade B-cell non-Hodgkin lymphomas

The vast spectrum of aggressive B-cell non-Hodgkin neoplasms (B-NHL) encompasses several infrequent entities occurring in association with viral infections, posing diagnostic challenges for practitioners. In the emerging era of precision oncology, the molecular characterization of malignancies has acquired paramount significance. The pathophysiological comprehension of specific entities and the identification of targeted therapeutic options have seen rapid development. However, owing to their rarity, not all entities have undergone exhaustive molecular characterization. Considerable heterogeneity exists in the extant body of work, both in terms of employed methodologies and the scale of cases studied. Presently, therapeutic strategies are predominantly derived from observations in diffuse large B-cell lymphoma (DLBCL), the most prevalent subset of aggressive B-NHL. Ongoing investigations into the molecular profiles of these uncommon virus-associated entities are progressively facilitating a clearer distinction from DLBCL, ultimately paving the way towards individualized therapeutic approaches. This review consolidates the current molecular insights into aggressive and virus-associated B-NHL, taking into consideration the recently updated 5th edition of the WHO classification of hematolymphoid tumors (WHO-5HAEM) and the International Consensus Classification (ICC). Additionally, potential therapeutically targetable susceptibilities are highlighted, offering a comprehensive overview of the present scientific landscape in the field.

Association of IL6 and IL10 gene promotor polymorphisms with susceptibility to acute necrotizing encephalopathy

Objective

Acute necrotizing encephalopathy (ANE) is a severe complication of infectious diseases affecting the brain and systemic organs. The main pathogenesis is cytokine storm, in which interleukin-6 (IL-6) and interleukin-10 (IL-10) are candidates for key cytokines. To further elucidate their roles in the etiology and pathogenesis of ANE, we studied polymorphisms in the promotor regions of the IL6 and IL10 genes by genetic and functional analyses.

Methods

We first conducted a case-control association study of four IL6 and three IL10 polymorphisms. We genotyped 31 Japanese ANE cases and compared the results with those of approximately 200 Japanese controls. For the two polymorphisms showing a possible association, we next studied whether the polymorphisms alter the production of IL-6 or IL-10 by lymphoblasts upon phorbol 12-myristate 13-acetate (PMA) stimulation.

Results

The frequencies of IL6 rs1800796G allele and IL10 rs1800871/rs1800872 CC/CC diplotype were significantly higher in ANE cases than in controls. The IL10 CC/CC diplotype was associated with low IL-10 production, whereas the IL6 GG genotype was not associated with IL-6 production.

Conclusion

IL10 rs1800871/rs1800872 CC/CC diplotype may predispose Japanese children to ANE by altering IL-10 production in the early phase of infection. Etio-pathogenetic significance of IL6 rs1800796G remains to be elucidated.

The role of viruses in HIV-associated lymphomas

Lymphomas are among the most common cancers in people with HIV (PWH). The lymphoma subtypes and pathogenesis of lymphoma in PWH are different from the immunocompetent population. It is well-known that HIV causes severe CD4+ T cell lymphopenia in the absence of antiretroviral therapy (ART); however, the risk of developing certain subtypes of lymphoma remains elevated even in people receiving ART with preserved CD4+ T cells. HIV contributes to lymphomagenesis and causes decreased immune surveillance via T cell depletion and dysregulation, B cell dysregulation, and the potential contribution of HIV-encoded proteins. The oncogenic gammaherpesviruses, Epstein-Barr virus (EBV) and Kaposi sarcoma herpesvirus (KSHV, also known as human herpesvirus 8), are the causative agents in the majority of HIV-associated lymphomas. HIV-associated T cell depletion and dysregulation allows EBV and KSHV to proliferate in infected B cells. Specific EBV- and KSHV-encoded proteins participate in B cell activation, and proliferation leading to B cell transformation. Understanding the distinct pathogenesis of HIV-associated lymphomas affords opportunities to develop therapies that specifically target these unique aspects and improve lymphoma outcomes in PWH. Agents being studied that target the specific roles of HIV, EBV, and KSHV in lymphomagenesis include immunotherapies, targeted agents, and cellular therapies.

[Human immunodeficiency virus and lymphoma]

Lymphomas remain a leading cause of morbidity and mortality for HIV-positive patients. The most common lymphomas include diffuse large B-cell lymphoma, Burkitt lymphoma, primary effusion lymphoma, plasmablastic lymphoma and Hodgkin lymphoma. Appropriate approach is determined by lymphoma stage, performans status, comorbidities, histological subtype, status of the HIV disease and immunosuppression. Treatment outcomes have improved due to chemotherapy modalities and effective antiretroviral therapy. This review summarizes epidemiology, pathogenesis, pathology, and current treatment landscape in HIV associated lymphoma.

HIV Lymphoma and Burkitts Lymphoma

Despite widely available antiretroviral therapy, lymphoma remains the leading cause of death for human immunodeficiency virus (HIV)-infected persons in economically developed countries. Even a few months of drug interruptions can lead to drops in the CD4 cell count, HIV viremia, and an increased risk of lymphoma. Currently, good HIV control facilitates intensive therapies appropriate to the lymphoma, including autologous and even allogeneic hematopoietic stem cell transplantation. Nonetheless, HIV-related lymphomas have unique aspects, including pathogenetic differences driven by the presence of HIV and often coinfection with oncogenic viruses. Future therapies might exploit these differences. Lymphoma subtypes also differ in the HIV-infected population, and the disease has a higher propensity for advanced-stage, aggressive presentation and extranodal disease. Other unique aspects include the need to avoid potential interactions between antiretroviral therapy and chemotherapeutic agents and the need for HIV-specific supportive care such as infection prophylaxis. Overall, the care of these patients has progressed sufficiently that recent guidelines from the American Society of Clinical Oncology advocate the inclusion of HIV-infected patients alongside HIV-negative patients in cancer clinical trials when appropriate. This article examines HIV lymphoma and includes Burkitt lymphoma in the general population.

Optimizing treatment of HIV-associated lymphoma

Cancer is the leading cause of death for HIV-infected persons in economically developed countries, even in the era of antiretroviral therapy (ART). Lymphomas remain a leading cause of cancer morbidity and mortality for HIV-infected patients and have increased incidence even in patients optimally treated with ART. Even limited interruptions of ART can lead to CD4 cell nadirs and HIV viremia, and increase the risk of lymphoma. The treatment of lymphoma is now similar for HIV-infected patients and the general population: patients with good HIV control can withstand intensive therapies appropriate to the lymphoma, including autologous and even allogeneic hematopoietic stem cell transplantation. Nonetheless, HIV-related lymphomas have unique aspects, including differences in lymphoma pathogenesis, driven by the presence of HIV, in addition to coinfection with oncogenic viruses. These differences might be exploited in the future to inform therapies. The relative incidences of lymphoma subtypes also differ in the HIV-infected population, and the propensity to advanced stage, aggressive presentation, and extranodal disease is higher. Other unique aspects include the need to avoid potential interactions between ART and chemotherapeutic agents, and the need for HIV-specific supportive care, such as infection prophylaxis. Despite these specific challenges for cancer treatment in the setting of HIV infection, the care of these patients has progressed sufficiently that recent guidelines from the American Society of Clinical Oncology advocate the inclusion of HIV-infected patients alongside HIV- patients in cancer clinical trials when appropriate.

Primary CNS lymphoma in HIV infection

Primary CNS lymphoma (PCNSL) has been designated an acquired immune deficiency syndrome (AIDS)-defining disease since 1983 and accounts for up to 15% of non-Hodgkin lymphomas in human immunodeficiency virus (HIV) patients. The majority of HIV patients are Epstein-Barr virus (EBV)-related. The most likely etiology is ineffective immunoregulation of EBV, inducing oncogenic protein expression, and subsequent loss of apoptosis and increased proliferation of lymphocytes. PCNSL generally presents with supratentorial, single or multiple, contrast-enhancing lesions. Neurologic symptoms can be headache, cognitive function disorders, focal neurologic, deficit and epilepsy. Differential diagnosis includes other oncologic or infectious causes, with cerebral toxoplasmosis being the most important. Magnetic resonance imaging characteristics, activity on ²⁰¹thallium single-photon emission computed tomography, presence of EBV DNA in the cerebrospinal fluid, and toxoplasmosis serology can make either PCNSL or cerebral toxoplasmosis more or less likely. However, definitive diagnosis of PCNSL relies on histopathologic confirmation. First-choice treatment is combination antiretroviral therapy in combination with high-dose methotrexate(-based) chemotherapy in patients in whom this is feasible. Combination antiretroviral therapy combined with whole-brain radiotherapy may be an alternative. Treatment of EBV with antiviral agents such as ganciclovir or zidovudine may be beneficial, but this needs further study. Prognosis of HIV-related PCNSL is poor, with median survival varying from 2 to 4 months, but patients treated with chemotherapy do better (median survival 1.5 years).

MicroRNA-related polymorphisms and non-Hodgkin lymphoma susceptibility in the Multicenter AIDS Cohort Study

BACKGROUND

MicroRNAs, small non-coding RNAs involved in gene regulation, are implicated in lymphomagenesis. We evaluated whether genetic variations in microRNA coding regions, binding sites, or biogenesis genes (collectively referred to as miRNA-SNPs) were associated with risk of AIDS-associated non-Hodgkin lymphoma (AIDS-NHL), and serum levels of four lymphoma-related microRNAs.

METHODS

Twenty-five miRNA-SNPs were genotyped in 180 AIDS-NHL cases and 529 HIV-infected matched controls from the Multicenter AIDS Cohort Study (MACS), and real-time polymerase chain reaction was used to quantify serum microRNA levels. Adjusted odds ratios (ORs) estimated using conditional logistic regression evaluated associations between miRNA-SNPs and AIDS-NHL risk. A semi-Bayes shrinkage approach was employed to reduce likelihood of false-positive associations. Adjusted mean ratios (MR) calculated using linear regression assessed associations between miRNA-SNPs and serum microRNA levels.

RESULTS

DDX20 rs197412, a non-synonymous miRNA biogenesis gene SNP, was associated with AIDS-NHL risk (OR=1.34 per minor allele; 95% CI: 1.02-1.75), and higher miRNA-222 serum levels nearing statistical significance (MR=1.21 per minor allele; 95% CI: 0.98-1.49). MiRNA-196a2 rs11614913 was associated with decreased central nervous system (CNS) AIDS-NHL (CT vs. CC OR=0.52; 95% CI: 0.27-0.99). The minor allele of HIF1A rs2057482, which creates a miRNA-196a2 binding site, was associated with systemic AIDS-NHL risk (OR=1.73 per minor allele; 95% CI: 1.12-2.67), and decreased CNS AIDS-NHL risk (OR=0.49 per minor allele; 95% CI: 0.25-0.94).

CONCLUSIONS

This study suggests that a few miRNA-SNPs are associated with AIDS-NHL risk and may modulate miRNA expression. These results support a role for miRNA in AIDS-NHL and may highlight pathways to be targeted for risk stratification or therapeutics.

The SDF-1 rs1801157 Polymorphism is Associated with Cancer Risk: An Update Pooled Analysis and FPRP Test of 17,876 Participants

The stromal cell derived factor-1 (SDF-1) rs1801157 gene polymorphism has been implicated in susceptibility to cancer, but the results were inconclusive. The current study was to precisely investigate the association between SDF-1 rs1801157 polymorphism and cancer risk using meta-analysis and the false positive report probability (FPRP) test. All 17,876 participants were included in the study. The meta-analysis results indicated a significant association between the SDF-1 rs1801157 polymorphism and cancer risk. By subgroup analyses, the results detected that the SDF-1 rs1801157 polymorphism was associated with cancer susceptibility among Asians and Caucasians. Additionally, we also found significant associations between the SDF-1 rs1801157 polymorphism and susceptibility to different types of cancer. However, to avoid a "false positive report", we further investigated the significant associations observed in the present meta-analysis using the FPRP test. Interestingly, the results of the FPRP test indicated that only 4 gene models were truly associated with cancer risk, especially in Asians. Moreover, we confirmed that the SDF-1 rs1801157 gene polymorphism was only associated with lung and urologic cancer risk. In summary, this study suggested that the SDF-1 rs1801157 polymorphism may serve as a risk factor for cancer development among Asians, especially an increased risk of urologic and lung cancers.

CD4+ and CD8+ T-cell kinetics in aviremic HIV-infected patients developing Hodgkin or non-Hodgkin lymphoma

OBJECTIVE

The risk of non-Hodgkin lymphoma (NHL) and Hodgkin lymphoma (HL) is increased in HIV-infected individuals. We studied the kinetics of lymphocyte subsets in patients who subsequently developed HL or NHL while on virologically suppressive antiretroviral therapy (ART).

DESIGN

Using a nested case-control design, cases of HIV+ HL or NHL were selected from two prospective clinical studies. Aviremia was defined as less than 200 HIV-RNA copies/ml for at least 6 months prior to lymphoma diagnosis. Each case was matched to three aviremic HIV+ controls without lymphoma.

RESULTS

In the 81 cases (50 HL and 31 NHL), prediagnostic CD4 T cells and CD8 T cells displayed discordant kinetics compared with controls. Within the last and within the next-to-last year preceding HL diagnosis, mean CD4 T cells decreased by -168 and by -2 cells/μl, compared with an increase of +44 and +73 cells/μl in the controls, respectively. Mean CD8 T cells decreased by -352 and -115 cells/μl, compared with nonsignificant changes of -29 and ±0 cells/μl in the controls, respectively. T-cell kinetics demonstrated a marked inter-individual variability. Kinetics of CD4 and CD8 T cells were also discordant between NHL cases and controls.

CONCLUSION

This study on a large number of aviremic patients developing HL and NHL who were carefully matched with controls, gives insights to prediagnostic kinetics of immune parameters. The discordant kinetics of both CD4 and CD8 T cells are already seen 1-2 years prior to lymphoma diagnosis, are more pronounced during the last year and in patients developing HL but are also seen in NHL.

Association of Interleukin-10 -3575T>A and -1082A>G polymorphisms with non-Hodgkin lymphoma susceptibility: a comprehensive review and meta-analysis

A number of studies have investigated the associations between IL-10 polymorphisms and non-Hodgkin lymphoma (NHL) susceptibility; however, the conclusions were still contradictory. To acquire a more precise estimation of the association, we performed the current meta-analysis. We systematically searched publications from EMBASE and MEDLINE, and calculated pooled odds ratios (ORs) and 95 % confidence intervals (CIs) using either fixed-effects or random-effects model. Genotype-based IL-10 mRNA expression analysis was performed using online public database of 270 individuals with three different ethnicities. A total of 10,703 cases and 11,823 controls from 10 studies were included for the -3575T>A polymorphism, 10,226 cases and 12,215 controls from 17 studies for the -1082A>G polymorphism. Pooled results indicated that IL-10 -3575T>A was associated with increased risk of diffuse large B cell lymphoma (DLBCL) and follicular lymphoma (FL), especially for Caucasians and hospital-based population. There was no association between IL-10 -1082A>G and NHL risk. However, subgroup analysis showed that IL-10 -1082GG might confer increased susceptibility to FL. In summary, this meta-analysis indicated that -3575T>A polymorphism was associated with altered NHL susceptibility for Caucasians and hospital-based population, especially for DLBCL and FL subtypes. The -1082A>G polymorphism may contribute to increased FL risk. Further large-scale population studies among different ethnicities are needed to validate these results.

Cancer prevention in HIV-infected populations

People living with human immunodeficiency virus (HIV) are living longer since the advent of effective combined antiretroviral therapy (cART). While cART substantially decreases the risk of developing some cancers, HIV-infected individuals remain at high risk for Kaposi sarcoma, lymphoma, and several solid tumors. Currently HIV-infected patients represent an aging group, and malignancies have become a leading cause of morbidity and mortality. Tailored cancer-prevention strategies are needed for this population. In this review we describe the etiologic agents and pathogenesis of common malignancies in the setting of HIV, as well as current evidence for cancer prevention strategies and screening programs.

Microenvironment abnormalities and lymphomagenesis: Immunological aspects

Innate and adaptive immune cells within the microenvironment identify and eliminate cells displaying signs of malignant potential. Immunosurveillance effector Natural Killer (NK) cells and Cytotoxic T Lymphocytes (CTL) identify malignant cells through germline receptors such as NKG2D and in the case of CTLs, presentation of antigen through the T cell receptor. Manipulation of immunosurveillance through altered tumor-identifying ligand expression or secretion, resistance to cytotoxicity, or compromised cytotoxic cell activity through immune tolerance mechanisms all contribute to failure of these systems to prevent cancer development. This review examines the diverse mechanisms by which alterations in the immune microenvironment can promote lymphomagenesis.

Association of IL10 -819C>T and -592C>A Polymorphisms with Non-Hodgkin Lymphoma Susceptibility: Evidence from Published Studies

Numerous studies have investigated the association of IL10 -819C>T and -592C>A polymorphisms with non-Hodgkin lymphoma (NHL) susceptibility, and yet reported conflicting results. With this in mind, we performed the current meta-analysis with an aim to verify actual causative variants underlying lymphomagenesis. Pooled odds ratios (ORs) and 95% confidence intervals (CIs) were calculated to evaluate the strength of the associations. Moreover, to explore the biological function of these polymorphisms, we also performed genotype-based mRNA expression analysis using online database derived from 270 subjects within three ethnicities. The final analysis included 11 studies with a total of 5859 NHL cases and 6893 controls for the IL10 -819C>T polymorphism, and 11 studies with 6277 cases and 7350 controls for the IL10 -592C>A polymorphism. No significant association was observed for these two polymorphisms in either the overall analysis or the stratification analyses by ethnicity and source of controls. Nevertheless, stratification analyses demonstrated a significant decreased risk associated with the IL10 -819C>T polymorphism (homozygous: OR=0.81, 95% CI=0.66-0.99, and recessive model: OR=0.80, 95%CI=0.65-0.98) and IL10 -592C>A polymorphism (homozygous: OR=0.80, 95% CI=0.66-0.99, and recessive model: OR=0.80, 95%CI=0.66-0.97) among patients with diffuse large B-cell lymphoma (DLBCL). Despite some limitations, this meta-analysis indicates that polymorphisms in IL10 gene may contribute to DLBCL susceptibility.

Polymorphisms in the IFNγ, IL-10, and TGFβ genes may be associated with HIV-1 infection

OBJECTIVE

This study investigated possible associations between the TNFα-308G/A, IFN+874A/T, IL-6-174C/G, IL-10-1082A/G, and TGFβ-509C/T polymorphisms with HIV-1 infection, in addition to correlation of the polymorphisms with clinical markers of AIDS progression, such as levels of CD4+/CD8+ T lymphocytes and plasma viral load.

METHODS

A total of 216 individuals who were infected with HIV-1 and on antiretroviral therapy (ART) and 294 individuals from the uninfected control group were analyzed.

RESULTS

All individuals evaluated were negative for total anti-HBc, anti-HCV, anti-T. pallidum, and anti-HTLV-1/2. The polymorphisms were identified by PCR-RFLP. Individuals presenting the IFN+874A allele as well as the AA genotype were more frequent in the HIV-1 infected group compared to the control group (P < 0.05), in addition to having lower levels of CD4+ T lymphocytes. The CD8+ T lymphocytes count was significantly lower in individuals with the IL-10-1082 GG genotype. The TGFβ-509TT genotype was associated with higher plasma viral load.

CONCLUSIONS

The results suggest that the presence of the IFN+874A allele confers susceptibility to HIV-1 infection and a decrease in the number of CD4+ T lymphocytes. In addition, the genotype associated with high serum levels of TGFβ may be associated with an increase in plasma viral load.

Circulating mediators of inflammation and immune activation in AIDS-related non-hodgkin lymphoma

BACKGROUND

Non-Hodgkin lymphoma (NHL) is the most common AIDS-related malignancy in developed countries. An elevated risk of developing NHL persists among HIV-infected individuals in comparison to the general population despite the advent of effective antiretroviral therapy. The mechanisms underlying the development of AIDS-related NHL (A-NHL) are not fully understood, but likely involve persistent B-cell activation and inflammation.

METHODS

This was a nested case-control study within the ongoing prospective Multicenter AIDS Cohort Study (MACS). Cases included 47 HIV-positive male subjects diagnosed with high-grade B-cell NHL. Controls were matched to each case from among participating HIV-positive males who did not develop any malignancy. Matching criteria included time HIV+ or since AIDS diagnosis, age, race and CD4+ cell count. Sera were tested for 161 serum biomarkers using multiplexed bead-based immunoassays.

RESULTS

A subset of 17 biomarkers, including cytokines, chemokines, acute phase proteins, tissue remodeling agents and bone metabolic mediators was identified to be significantly altered in A-NHL cases in comparison to controls. Many of the biomarkers included in this subset were positively correlated with HIV viral load. A pathway analysis of our results revealed an extensive network of interactions between current and previously identified biomarkers.

CONCLUSIONS

These findings support the current hypothesis that A-NHL develops in the context of persistent immune stimulation and inflammation. Further analysis of the biomarkers identified in this report should enhance our ability to diagnose, monitor and treat this disease.

Analysis of interleukin-10 promoter single nucleotide polymorphisms and risk of non-Hodgkin lymphoma in a Malaysian population

We evaluated the association of two IL10 single nucleotide polymorphisms (SNPs) (rs1800896 and rs1800871) with non-Hodgkin lymphoma (NHL) risk in the three major races of the Malaysian population (Malay, Chinese and Indian; 317 cases and 330 controls). Our initial screening demonstrated that rs1800871 but not rs1800896 was significantly associated with increased NHL risk in Malays (pMalay-Rec = 0.007) and Chinese only (pChinese-Rec = 0.039). Subsequent combined analysis of the Malay and Chinese revealed significant association of rs1800871 with all (ALL) NHL subtypes (pMeta-ALL-NHL-Rec = 0.001), ALL B-cell subtypes (pMeta-ALL-B-cell-Rec = 0.003), diffuse large B-cell lymphoma (DLBCL) subtype (pMeta-DLBCL-Rec = 0.002) and ALL T-cell subtypes (pMeta-ALL-T-cell-Rec = 0.031). SNP rs1800896 showed increased risk only in follicular lymphoma (FL) (pMeta-FL-Dom = 0.0004). We also detected a male-specific association of rs1800871 with increased NHL risk (pMeta-Male-ALL-NHL-Rec = 0.006) in the combined analysis. To our knowledge, this is the first report on the association of IL10 promoter SNPs with NHL susceptibility in the three major races of Malaysia.

Serum levels of cytokines and biomarkers for inflammation and immune activation, and HIV-associated non-Hodgkin B-cell lymphoma risk

BACKGROUND

HIV infection is associated with a marked increase in risk for non-Hodgkin lymphoma (AIDS-NHL). However, the mechanisms that promote the development of AIDS-NHL are not fully understood.

METHODS

In this study, serum levels of several cytokines and other molecules associated with immune activation were measured in specimens collected longitudinally during 1 to 5 years preceding AIDS-NHL diagnosis, in 176 AIDS-NHL cases and 176 HIV(+) controls from the Multicenter AIDS Cohort Study (MACS).

RESULTS

Multivariate analyses revealed that serum levels of immunoglobulin free light chains (FLC), interleukin (IL)-6, IL-10, IP-10/CXCL10, neopterin, and TNF-α were elevated in those HIV(+) individuals who went on to develop AIDS-NHL. In addition, the fraction of specimens with detectable IL-2 was increased and the fraction with detectable IL-4 was decreased in these subjects.

CONCLUSIONS

These results suggest that long-term, chronic immune activation, possibly driven by macrophage-produced cytokines, precedes development of NHL in HIV(+) individuals.

IMPACT

FLC, IL-6, IL-10, IP-10/CXCL10, neopterin, and TNF-α may serve as biomarkers for AIDS-NHL. .

Association between interleukin-4 -590C > T polymorphism and non-Hodgkin's lymphoma risk

Many studies were performed to assess the association between IL-4 -590C > T polymorphism and non-Hodgkin's lymphoma (NHL) risk, but no consensus was available up to now. We conducted a meta-analysis to examine the association between IL-4 -590C > T polymorphism and NHL risk. We used odds ratios (ORs) to assess the strength of the association and 95% confidence intervals (CIs) to give a sense of the precision of the estimate. A total of six studies were found to be eligible for meta-analyses of IL-4 -590C > T variant. Results from this study showed that IL-4 -590C > T polymorphism was not significantly associated with NHL risk under all genetic models in overall population. Further sensitivity analysis confirmed the results. In subgroup analyses stratified by race, no significant association was found in either Caucasian or mixed populations. The meta-analysis indicated that elected -590C > T polymorphism of IL-4 may not be a risk factor for NHL development.

B-cell stimulatory cytokines and markers of immune activation are elevated several years prior to the diagnosis of systemic AIDS-associated non-Hodgkin B-cell lymphoma

BACKGROUND

The risk of developing non-Hodgkin lymphoma (NHL) is greatly increased in HIV infection. The aim of this study was to determine whether elevated serum levels of molecules associated with B-cell activation precede the diagnosis of AIDS-associated NHL (AIDS-NHL).

METHODS

Serum levels of B-cell activation-associated molecules, interleukin (IL)6, IL10, soluble CD23 (sCD23), sCD27, sCD30, C-reactive protein (CRP), and immunoglobulin E were determined in 179 NHL cases and HIV+ controls in the Multicenter AIDS Cohort Study, collected at up to 3 time points per subject, 0 to 5 years prior to AIDS-NHL diagnosis.

RESULTS

Serum IL6, IL10, CRP, sCD23, sCD27, and sCD30 levels were all significantly elevated in the AIDS-NHL group, when compared with HIV+ controls or with AIDS controls, after adjusting for CD4 T-cell number. Elevated serum levels of B-cell activation-associated molecules were seen to be associated with the development of systemic [non-CNS (central nervous system)] NHL, but not with the development of primary CNS lymphoma.

CONCLUSIONS

Levels of certain B-cell stimulatory cytokines and molecules associated with immune activation are elevated for several years preceding the diagnosis of systemic AIDS-NHL. This observation is consistent with the hypothesis that chronic B-cell activation contributes to the development of these hematologic malignancies.

IMPACT

Marked differences in serum levels of several molecules are seen for several years prediagnosis in those who eventually develop AIDS-NHL. Some of these molecules may serve as candidate biomarkers and provide valuable information to better define the etiology of NHL.

HIV-associated immune dysfunction and viral infection: role in the pathogenesis of AIDS-related lymphoma

HIV infection is associated with a much higher risk for the development of non-Hodgkin lymphoma (AIDS-NHL). The principal causes of lymphomagenesis in HIV-infected individuals are thought to be the loss of immune function seen in HIV infection, which results in the loss of immunoregulation of Epstein-Barr virus-infected B cells, as well as HIV infection-associated immune dysregulation, including chronic B-cell activation. In this review, we discuss recent reports that further support the importance of these factors, and we highlight emerging evidence of different mechanisms that potentially drive lymphomagenesis in HIV-infected individuals.

Kaposi sarcoma-associated herpesvirus serum DNA and antibodies not associated with subsequent non-Hodgkin lymphoma risk

Kaposi sarcoma-associated herpes virus (KSHV) infects B-cells and is found in non-Hodgkin lymphoma (NHL) B-cell tumors and could therefore contribute to the occurrence of NHL. We performed a nested case-control study including 155 incident NHL cases and matched noncancer controls. Pre-NHL serum was tested for KSHV DNA and antibodies. Serum KSHV DNA was more common in cases than controls (14% versus 6%, P = 0.03), but after adjustment, the difference was not significant. Epstein-Barr virus serum DNA was similarly unassociated with NHL as were KSHV antibodies. KSHV is not a primary cause of NHL in HIV-infected men who have sex with men.

Cancer biomarkers in HIV patients

PURPOSE OF REVIEW

In this review, we update investigations related to cancer biomarkers in HIV-infected populations.

RECENT FINDINGS

CD4 lymphocyte count is associated with primary central nervous system lymphoma (PCNSL), systemic non-Hodgkin's lymphoma (NHL) (except perhaps for Burkitt lymphoma), Kaposi's sarcoma, cervical cancer, and anal cancer. HIV load is associated with Burkitt lymphoma and systemic NHL (but not PCNSL), with Kaposi's sarcoma and with anal cancer. CD40 ligand incorporated into the HIV envelope and expression of activation-induced cytidine deaminase may help explain the relationship between HIV load and Burkitt lymphoma. Genetic polymorphisms have been identified that are linked to lymphoma in HIV patients. B-cell activation as manifest in immunoglobulin light chain production may be an important marker for NHL risk. Cytokines and related molecules (IL10, sCD30) may identify patients at high risk for NHL. Epstein-Barr virus (EBV) in cerebrospinal fluid (CSF) is useful as a marker for PCNSL, although with the falling incidence of PCNSL, the specificity of the test has been called into question. EBV and Kaposi's sarcoma-associated herpesvirus (KSHV) have not yet emerged as especially promising markers of risk for either lymphoma or Kaposi's sarcoma.

SUMMARY

CD4 lymphocyte count, HIV load, germline genetic polymorphisms, cytokine and related molecules, and immunoglobulin light chains all show increasing promise as biomarkers of malignancy in HIV patients.