Genetic overlap between autoimmune diseases and non-Hodgkin lymphoma subtypes.

Epidemiologic studies show an increased risk of non-Hodgkin lymphoma (NHL) in patients with autoimmune disease (AD), due to a combination of shared environmental factors and/or genetic factors, or a causative cascade: chronic inflammation/antigen-stimulation in one disease leads to another. Here we assess shared genetic risk in genome-wide-association-studies (GWAS). Secondary analysis of GWAS of NHL subtypes (chronic lymphocytic leukemia, diffuse large B-cell lymphoma, follicular lymphoma, and marginal zone lymphoma) and ADs (rheumatoid arthritis, systemic lupus erythematosus, and multiple sclerosis). Shared genetic risk was assessed by (a) description of regional genetic of overlap, (b) polygenic risk score (PRS), (c)"diseasome", (d)meta-analysis. Descriptive analysis revealed few shared genetic factors between each AD and each NHL subtype. The PRS of ADs were not increased in NHL patients (nor vice versa). In the diseasome, NHLs shared more genetic etiology with ADs than solid cancers (p = .0041). A meta-analysis (combing AD with NHL) implicated genes of apoptosis and telomere length. This GWAS-based analysis four NHL subtypes and three ADs revealed few weakly-associated shared loci, explaining little total risk. This suggests common genetic variation, as assessed by GWAS in these sample sizes, may not be the primary explanation for the link between these ADs and NHLs.

Infectious mononucleosis, immune genotypes, and non-Hodgkin lymphoma (NHL): an InterLymph Consortium study.

PURPOSE: We explored the interaction between non-Hodgkin lymphoma (NHL), infectious mononucleosis (IM) history, and immune-related genotypes in a pooled case-control analysis. METHODS: A total of 7,926 NHL patients and 10,018 controls from 12 case-control studies were included. Studies were conducted during various time periods between 1988 and 2008, and participants were 17-96 years of age at the time of ascertainment/recruitment. Self-reported IM history and immune response genotypes were provided by the InterLymph Data Coordinating Center at Mayo Clinic. Odds ratios (OR) were estimated using multivariate logistic regression, and interactions were estimated using the empirical Bayes method. PACT was used to account for multiple comparisons. RESULTS: There was evidence of an interaction effect between IM history and two variants on T-cell lymphoma (TCL) risk: rs1143627 in interleukin-1B (IL1B) (pinteraction = 0.04, ORinteraction = 0.09, 95% confidence interval [CI] 0.01, 0.87) and rs1800797 in interleukin-6 (IL6) (pinteraction = 0.03, ORinteraction = 0.08, 95% CI 0.01, 0.80). Neither interaction effect withstood adjustment for multiple comparisons. There were no statistically significant interactions between immune response genotypes and IM on other NHL subtypes. CONCLUSIONS: Genetic risk variants in IL1B and IL6 may affect the association between IM and TCL, possibly by influencing T-cell activation, growth, and differentiation in the presence of IM, thereby decreasing risk of immune cell proliferation.

Correction to: Infectious mononucleosis, immune genotypes, and non-Hodgkin lymphoma (NHL): an InterLymph Consortium study.

Unfortunately, the word "Group" is missed in the article title of the original publication. It has been corrected by this erratum.

Aspirin intake and breast cancer survival - a nation-wide study using prospectively recorded data in Sweden.

BACKGROUND: Aspirin (ASA) use has been associated with improved breast cancer survival in several prospective studies. METHODS: We conducted a nested case-control study of ASA use after a breast cancer diagnosis among women using Swedish National Registries. We assessed prospectively recorded ASA exposure during several different time windows following cancer diagnosis using conditional logistic regression with breast cancer death as the main outcome. Within each six-month period of follow-up, we categorized dispensed ASA doses into three groups: 0, less than 1, and 1 or more daily doses. RESULTS: We included 27,426 women diagnosed with breast cancer between 2005 and 2009; 1,661 died of breast cancer when followed until Dec 31, 2010. There was no association between ASA use and breast cancer death when exposure was assessed either shortly after diagnosis, or 3-12 months before the end of follow-up. Only during the period 0-6 months before the end of follow-up was ASA use at least daily compared with non-use associated with a decreased risk of breast cancer death: HR (95% CI) =0.69 (0.56-0.86). However, in the same time-frame, those using ASA less than daily had an increased risk of breast cancer death: HR (95% CI) =1.43 (1.09-1.87). CONCLUSIONS: Contrary to other studies, we did not find that ASA use was associated with a lower risk of death from breast cancer, except when assessed short term with no delay to death/end of follow-up, which may reflect discontinuation of ASA during terminal illness.

Short telomere length is associated with NOTCH1/SF3B1/TP53 aberrations and poor outcome in newly diagnosed chronic lymphocytic leukemia patients.

Most previous studies on telomere length (TL) in chronic lymphocytic leukemia (CLL) are based on referral cohorts including a high proportion of aggressive cases. Here, the impact of TL was analyzed in a population-based cohort of newly diagnosed CLL (n = 265) and in relation to other prognostic markers. Short telomeres were particularly associated with high-risk genetic markers, such as NOTCH1, SF3B1, or TP53 aberrations, and predicted a short time to treatment (TTT) and overall survival (OS) (both P < 0.0001). TL was an independent prognostic factor and subdivided patients with otherwise good-prognostic features (e.g., mutated IGHV genes, favorable cytogenetics) into subgroups with different outcome. Furthermore, in follow-up samples (n = 119) taken 5-8 years after diagnosis, TL correlated well with TL at diagnosis and remained unaffected by treatment. Altogether, these novel data indicate that short TL already at diagnosis is associated with poor outcome in CLL and that TL can be measured at later stages of the disease.

Self-reported history of infections and the risk of non-Hodgkin lymphoma: an InterLymph pooled analysis.

We performed a pooled analysis of data on self-reported history of infections in relation to the risk of non-Hodgkin lymphoma (NHL) from 17 case-control studies that included 12,585 cases and 15,416 controls aged 16-96 years at recruitment. Pooled odds ratios (OR) and 95% confidence intervals (95% CI) were estimated in two-stage random-effect or joint fixed-effect models, adjusting for age, sex and study centre. Data from the 2 years before diagnosis (or date of interview for controls) were excluded. A self-reported history of infectious mononucleosis was associated with an excess risk of NHL (OR = 1.26, 95% CI = 1.01-1.57 based on data from 16 studies); study-specific results indicate significant (I(2) = 51%, p = 0.01) heterogeneity. A self-reported history of measles or whooping cough was associated with an approximate 15% reduction in risk. History of other infection was not associated with NHL. We find little clear evidence of an association between NHL risk and infection although the limitations of data based on self-reported medical history (particularly of childhood illness reported by older people) are well recognized.

Vitamin D receptor genotypes, ultraviolet radiation exposure, and risk of non-Hodgkin lymphoma.

Ultraviolet radiation (UVR) exposure may influence risk of non-Hodgkin lymphoma (NHL) through vitamin D, with antineoplastic effects mediated through the vitamin D receptor (VDR). To explore the role of vitamin D in NHL risk and the potential interaction with UVR, the authors genotyped 10 VDR polymorphisms in 2,448 NHL patients and 1,981 controls from Denmark and Sweden who were recruited in 1999-2002. Odds ratios and 95% confidence intervals were computed with logistic regression. P values were 2-sided. Most VDR variants (e.g., rs731236/TaqI, rs15444410/BsmI) were not associated with overall risk of NHL, but there was some evidence of a positive association between rs4760655 and follicular lymphoma risk (nominal P(trend) = 0.004, corrected P(trend) = 0.24). There was no support for an effect of interaction between VDR variants and UVR exposure on risk of overall NHL or B-cell lymphoma subtypes. However, there was some evidence that rs731236 altered associations between UVR and T-cell NHL risk; while increasing UVR frequency lowered T-cell NHL risk among rs731236 TT carriers, an elevated risk was observed among rs731236 CC carriers (nominal P(interaction) ≤ 0.008, corrected P(interaction) ≥ 0.12). VDR does not appear to harbor major determinants of NHL risk, except perhaps for follicular lymphoma. Possible heterogeneity in effects of UVR exposure on T-cell lymphoma risk by VDR rs731236 genotype merits further investigation.

LPL is the strongest prognostic factor in a comparative analysis of RNA-based markers in early chronic lymphocytic leukemia.

BACKGROUND: The expression levels of LPL, ZAP70, TCL1A, CLLU1 and MCL1 have recently been proposed as prognostic factors in chronic lymphocytic leukemia. However, few studies have systematically compared these different RNA-based markers. DESIGN AND METHODS: Using real-time quantitative PCR, we measured the mRNA expression levels of these genes in unsorted samples from 252 newly diagnosed chronic lymphocytic leukemia patients and correlated our data with established prognostic markers (for example Binet stage, CD38, IGHV gene mutational status and genomic aberrations) and clinical outcome. RESULTS: High expression levels of all RNA-based markers, except MCL1, predicted shorter overall survival and time to treatment, with LPL being the most significant. In multivariate analysis including the RNA-based markers, LPL expression was the only independent prognostic marker for overall survival and time to treatment. When studying LPL expression and the established markers, LPL expression retained its independent prognostic strength for overall survival. All of the RNA-based markers, albeit with varying ability, added prognostic information to established markers, with LPL expression giving the most significant results. Notably, high LPL expression predicted a worse outcome in good-prognosis subgroups, such as patients with mutated IGHV genes, Binet stage A, CD38 negativity or favorable cytogenetics. In particular, the combination of LPL expression and CD38 could further stratify Binet stage A patients. CONCLUSIONS: LPL expression is the strongest RNA-based prognostic marker in chronic lymphocytic leukemia that could potentially be applied to predict outcome in the clinical setting, particularly in the large group of patients with favorable prognosis.

Array-based genomic screening at diagnosis and during follow-up in chronic lymphocytic leukemia.

BACKGROUND: High-resolution genomic microarrays enable simultaneous detection of copy-number aberrations such as the known recurrent aberrations in chronic lymphocytic leukemia [del(11q), del(13q), del(17p) and trisomy 12], and copy-number neutral loss of heterozygosity. Moreover, comparison of genomic profiles from sequential patients' samples allows detection of clonal evolution. DESIGN AND METHODS: We screened samples from 369 patients with newly diagnosed chronic lymphocytic leukemia from a population-based cohort using 250K single nucleotide polymorphism-arrays. Clonal evolution was evaluated in 59 follow-up samples obtained after 5-9 years. RESULTS: At diagnosis, copy-number aberrations were identified in 90% of patients; 70% carried known recurrent alterations, including del(13q) (55%), trisomy 12 (10.5%), del(11q) (10%), and del(17p) (4%). Additional recurrent aberrations were detected on chromosomes 2 (1.9%), 4 (1.4%), 8 (1.6%) and 14 (1.6%). Thirteen patients (3.5%) displayed recurrent copy-number neutral loss of heterozygosity on 13q, of whom 11 had concurrent homozygous del(13q). Genomic complexity and large 13q deletions correlated with inferior outcome, while the former was linked to poor-prognostic aberrations. In the follow-up study, clonal evolution developed in 8/24 (33%) patients with unmutated IGHV, and in 4/25 (16%) IGHV-mutated and treated patients. In contrast, untreated patients with mutated IGHV (n=10) did not acquire additional aberrations. The most common secondary event, del(13q), was detected in 6/12 (50%) of all patients with acquired alterations. Interestingly, aberrations on, for example, chromosome 6q, 8p, 9p and 10q developed exclusively in patients with unmutated IGHV. CONCLUSIONS: Whole-genome screening revealed a high frequency of genomic aberrations in newly diagnosed chronic lymphocytic leukemia. Clonal evolution was associated with other markers of aggressive disease and commonly included the known recurrent aberrations.

Adaptation of the Charlson Comorbidity Index for Register-Based Research in Sweden.

PURPOSE: Comorbidity indices are often used to measure comorbidities in register-based research. We aimed to adapt the Charlson comorbidity index (CCI) to a Swedish setting. METHODS: Four versions of the CCI were compared and evaluated by disease-specific experts. RESULTS: We created a cohesive coding system for CCI to 1) harmonize the content between different international classification of disease codes (ICD-7,8,9,10), 2) delete incorrect codes, 3) enhance the distinction between mild, moderate or severe disease (and between diabetes with and without end-organ damage), 4) minimize duplication of codes, and 5) briefly explain the meaning of individual codes in writing. CONCLUSION: This work may provide an integrated and efficient coding algorithm for CCI to be used in medical register-based research in Sweden.

Birth order and risk of non-hodgkin lymphoma--true association or bias?

There is inconsistent evidence that increasing birth order may be associated with risk of non-Hodgkin lymphoma (NHL). The authors examined the association between birth order and related variables and NHL risk in a pooled analysis (1983-2005) of 13,535 cases and 16,427 controls from 18 case-control studies within the International Lymphoma Epidemiology Consortium (InterLymph). Overall, the authors found no significant association between increasing birth order and risk of NHL (P-trend = 0.082) and significant heterogeneity. However, a significant association was present for a number of B- and T-cell NHL subtypes. There was considerable variation in the study-specific risks which was partly explained by study design and participant characteristics. In particular, a significant positive association was present in population-based studies, which had lower response rates in cases and controls, but not in hospital-based studies. A significant positive association was present in higher-socioeconomic-status (SES) participants only. Results were very similar for the related variable of sibship size. The known correlation of high birth order with low SES suggests that selection bias related to SES may be responsible for the association between birth order and NHL.

Borrelia infection and risk of non-Hodgkin lymphoma.

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

Distinct gene expression profiles in subsets of chronic lymphocytic leukemia expressing stereotyped IGHV4-34 B-cell receptors.

BACKGROUND: Numerous subsets of patients with chronic lymphocytic leukemia display similar immunoglobulin gene usage with almost identical complementarity determining region 3 sequences. Among IGHV4-34 cases, two such subsets with "stereotyped" B-cell receptors were recently identified, i.e. subset #4 (IGHV4-34/IGKV2-30) and subset #16 (IGHV4-34/IGKV3-20). Subset #4 patients appear to share biological and clinical features, e.g. young age at diagnosis and indolent disease, whereas little is known about subset #16 at a clinical level. DESIGN AND METHODS: We investigated the global gene expression pattern in sorted chronic lymphocytic leukemia cells from 25 subset/non-subset IGHV4-34 patients using Affymetrix gene expression arrays. RESULTS: Although generally few differences were found when comparing subset to non-subset 4/16 IGHV4-34 cases, distinct gene expression profiles were revealed for subset #4 versus subset #16. The differentially expressed genes, predominantly with lower expression in subset #4 patients, are involved in important cell regulatory pathways including cell-cycle control, proliferation and immune response, which may partly explain the low-proliferative disease observed in subset #4 patients. CONCLUSIONS: Our novel data demonstrate distinct gene expression profiles among patients with stereotyped IGHV4-34 B-cell receptors, providing further evidence for biological differences in the pathogenesis of these subsets and underscoring the functional relevance of subset assignment based on B-cell receptor sequence features.

Immunosuppressive treatment after solid organ transplantation and risk of post-transplant cutaneous squamous cell carcinoma.

BACKGROUND: The risk of cutaneous squamous cell carcinoma (CSCC) is found to be substantially increased after organ transplantation. The association with specific immunosuppressive regimens has been previously investigated, but results are not concordant. We aimed to clarify the relationship between separate immunosuppressive drugs, drug load, timing and risk of post-transplant CSCC. METHODS: A population-based nested case-control study was performed in the Swedish organ transplantation cohort (n = 5931). All patients who developed CSCC during the follow-up (1970-97) were eligible as cases (n = 207). Controls (n = 189) were randomly selected from the cohort and individually matched to the cases on follow-up time, age at and calendar period of transplantation. Exposure information was collected through extensive and standardized review of medical records. RESULTS: The median time to CSCC was 6.7 years. Post-transplant azathioprine (Aza) treatment considerably increased the risk of CSCC during all time periods analysed, and the risk augmented with increasing dose and duration. Patients who after the entire follow-up period had received a high accumulated dose of Aza had an 8.8-fold increased risk of CSCC in multivariate analysis (P < 0.0001), compared to patients never treated with Aza. Additionally, a high accumulated dose of corticosteroids during the same period conferred a 3.9-fold elevated risk of CSCC (P = 0.09), compared to the lowest accumulated dose of corticosteroids. Cyclosporine treatment was not associated with the risk of CSCC post-transplantation. CONCLUSIONS: This study provides evidence that Aza treatment, but not cyclosporine treatment, is strongly associated with post-transplant CSCC risk. The results suggest that the risk of CSCC after organ transplantation is not only an effect of the immunosuppressive load per se.

Immunoglobulin subclass levels in patients with non-Hodgkin lymphoma.

Allergy/atopy has been suggested to protect against non-Hodgkin lymphoma (NHL) and specific IgE levels are decreased in patients with NHL. We speculated that all immunoglobulin subclass levels might be downregulated in NHL and examined levels of IgM, IgD, IgA, IgE, IgG and IgG(4) in 200 NHL patients and 200 age- and sex-matched controls. Patients with B-cell NHL of many types had consistently lower median immunoglobulin subclass levels than controls. In every subclass except IgD, about 10-15% of B-cell NHL patients had absolute levels below the 2.5 percentile of controls. Subclass levels correlated with each other and many patients had more than one significantly low level. Levels were lowest for IgG(4) and IgE. Patients with chronic lymphocytic leukemia/small lymphocytic lymphoma had especially low total IgE levels. In other B-cell NHL types, total IgE levels were decreased to a similar extent as other immunoglobulin subclasses. In conclusion, low IgE levels are only part of a more generalized loss of immunoglobulins of all subtypes in a wide variety of B-cell NHL types. Low immunoglobulin levels appear to be a consequence of B-cell NHL presence, and we speculate about molecular mechanisms that could reduce all immunoglobulin subclasses in B-cell NHL.

Serum YKL-40 and interleukin 6 levels in Hodgkin lymphoma.

PURPOSE: Serum levels of the inflammatory markers YKL-40 and interleukin 6 (IL-6) are increased in many conditions, including cancers. We examined serum YKL-40 and IL-6 levels in patients with Hodgkin lymphoma, a tumor with strong immunologic reaction to relatively few tumor cells, especially in nodular sclerosis Hodgkin lymphoma. EXPERIMENTAL DESIGN: We analyzed Danish and Swedish patients with incident Hodgkin lymphoma (N=470) and population controls from Denmark (n=245 for YKL-40; n=348 for IL-6). Serum YKL-40 and IL-6 levels were determined by ELISA, and log-transformed data were analyzed by linear regression, adjusting for age and sex. RESULTS: Serum levels of YKL-40 and IL-6 increased in Hodgkin lymphoma patients compared with controls (YKL-40, 3.6-fold; IL-6, 8.3-fold; both, P<0.0001). In pretreatment samples from pretreatment Hodgkin lymphoma patients (n=176), levels were correlated with more advanced stages (P(trend), 0.0001 for YKL-40 and 0.013 for IL-6) and in those with B symptoms; however, levels were similar in nodular sclerosis and mixed cellularity subtypes, by EBV status, and in younger (<45 years old) and older patients. Patients tested soon after treatment onset had significantly lower levels than pretreatment patients; however, even >or=6 months after treatment onset, serum YKL-40 and IL-6 levels remained significantly increased compared with controls. In patients who died (n=12), pretreatment levels for YKL-40 and IL-6 were higher than in survivors, although not statistically significantly. CONCLUSIONS: Serum YKL-40 and IL-6 levels were increased in untreated Hodgkin lymphoma patients and those with more advanced stages but did not differ significantly by Hodgkin lymphoma histology. Following treatment, serum levels were significantly lower.

Screening for copy-number alterations and loss of heterozygosity in chronic lymphocytic leukemia--a comparative study of four differently designed, high resolution microarray platforms.

Screening for gene copy-number alterations (CNAs) has improved by applying genome-wide microarrays, where SNP arrays also allow analysis of loss of heterozygozity (LOH). We here analyzed 10 chronic lymphocytic leukemia (CLL) samples using four different high-resolution platforms: BAC arrays (32K), oligonucleotide arrays (185K, Agilent), and two SNP arrays (250K, Affymetrix and 317K, Illumina). Cross-platform comparison revealed 29 concordantly detected CNAs, including known recurrent alterations, which confirmed that all platforms are powerful tools when screening for large aberrations. However, detection of 32 additional regions present in 2-3 platforms illustrated a discrepancy in detection of small CNAs, which often involved reported copy-number variations. LOH analysis using dChip revealed concordance of mainly large regions, but showed numerous, small nonoverlapping regions and LOH escaping detection. Evaluation of baseline variation and copy-number ratio response showed the best performance for the Agilent platform and confirmed the robustness of BAC arrays. Accordingly, these platforms demonstrated a higher degree of platform-specific CNAs. The SNP arrays displayed higher technical variation, although this was compensated by high density of elements. Affymetrix detected a higher degree of CNAs compared to Illumina, while the latter showed a lower noise level and higher detection rate in the LOH analysis. Large-scale studies of genomic aberrations are now feasible, but new tools for LOH analysis are requested.

Infectious mononucleosis, childhood social environment, and risk of Hodgkin lymphoma.

Infectious mononucleosis (IM) has been associated with an increased risk of Hodgkin lymphoma (HL), implicating a role for Epstein-Barr virus (EBV) in HL development. Although essential to the understanding of the association, it has remained uncertain if the relationship is restricted to the EBV-positive subset of HL. We collected information on mononucleosis history and childhood socioenvironmental characteristics in a population-based study of 586 patients with classic HL and 3,187 controls in Denmark and Sweden. Tumor EBV status was established for 499 cases by immunohistochemistry and in situ hybridization techniques. Odds ratios (OR) for the relationship between HL risk and mononucleosis and other risk factors were estimated by logistic regression for HL in younger (18-44 years) and older (45-74 years) adults, overall and by tumor EBV status. All analyses were adjusted for country-specific measures of maternal education and mononucleosis history. IM was associated with an increased risk of EBV-positive [OR, 3.23; 95% confidence interval (95% CI) 1.89-5.55] but not EBV-negative HL (OR, 1.35; 95% CI, 0.86-2.14). Risk of EBV-positive HL varied with time since IM and was particularly pronounced in younger adults (OR, 3.96; 95% CI, 2.19-7.18). IM-associated lymphomas occurred with a median of 2.9 years (1.8-4.9 years) after infection. The EBV specificity of the IM association was corroborated by a case-case comparison of IM history between younger adult EBV-positive and EBV-negative HL patients (OR(IM EBV+ HL versus EBV- HL), 2.68; 95% CI, 1.40-5.12). We found further evidence that IM is associated only with EBV-positive HL. This finding is compatible with the notion that EBV-positive and EBV-negative HL may have different etiologies.

Targetable genetic alterations of TCF4 (E2-2) drive immunoglobulin expression in diffuse large B cell lymphoma.

The activated B cell (ABC-like) subtype of diffuse large B cell lymphoma (DLBCL) is characterized by chronic activation of signaling initiated by immunoglobulin µ (IgM). By analyzing the DNA copy number profiles of 1000 DLBCL tumors, we identified gains of 18q21.2 as the most frequent genetic alteration in ABC-like DLBCL. Using integrative analysis of matched gene expression profiling data, we found that the TCF4 (E2-2) transcription factor gene was the target of these alterations. Overexpression of TCF4 in ABC-like DLBCL cell lines led to its occupancy on immunoglobulin (IGHM) and MYC gene enhancers and increased expression of these genes at the transcript and protein levels. Inhibition of TCF4 activity with dominant-negative constructs was synthetically lethal to ABC-like DLBCL cell lines harboring TCF4 DNA copy gains, highlighting these gains as an attractive potential therapeutic target. Furthermore, the TCF4 gene was one of the top BRD4-regulated genes in DLBCL cell lines. BET proteolysis-targeting chimera (PROTAC) ARV771 extinguished TCF4, MYC, and IgM expression and killed ABC-like DLBCL cells in vitro. In DLBCL xenograft models, ARV771 treatment reduced tumor growth and prolonged survival. This work highlights a genetic mechanism for promoting immunoglobulin signaling in ABC-like DLBCL and provides a functional rationale for the use of BET inhibitors in this disease.

Hepatitis C infection and risk of malignant lymphoma.

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