Citations

Abstract Abstract 3637 Background: A recent large genome-wide association study confirmed the important role of the major histocompatibility complex in classical Hodgkin Lymphoma (cHL) susceptibility (rs6903608), but also identified significant associations with genetic variants outside of the HLA region at chromosomal regions 2p16.1 (REL, rs1432295), 8q24.21 (PVT1, rs2608053, rs2019960), and 10p14 (GATA3, rs501764, rs485411). These single nucleotide polymorphisms (SNPs) are localized in or near important genes involved in lymphoma pathogenesis: REL, which encodes for c-rel, is a member of NFkB pathway; PVT1, which is downstream of the MYC locus, encodes for non-coding microRNAs, some of which have oncogenic properties; and GATA3, which is a critical transcriptional factor for priming lymphoid T-cells for Th2 phenotype, is aberrantly expressed in HL. We investigated whether these six SNPs described in cHL etiology also influence the outcome of newly diagnosed cHL patients in two independent cohorts. Patients and Methods: The first cohort consisted of 342 cHL patients from the Groupe d'Etude des Lymphomes de l'Adulte (GELA) who were prospectively enrolled between 1998 and 2002. The second cohort consisted of 259 patients prospectively enrolled in the University of Iowa/Mayo Clinic SPORE Molecular Epidemiology Resource (MER). DNA for genotyping was extracted from a blood samples collected at diagnosis, and genotyping was conducted using Taqman technology (ABI Prism 7000, Applied Biosystems) for HLA-DRA, PVT1, GATA3 and PCR-based restriction fragment length polymorphism for REL in GELA cohort and Illumina iSelect for the 6 SNPs in MER cohort. Both cohorts were followed for disease progression, re-treatment and death. In the GELA series, the median age was 32 years (range, 15–93), 57% were male, and 72% had an Ann Arbor stage I–II. Histology was nodular sclerosis in 84%, and 29% of available cases (n=40/140) were EBV positive. In the MER series, the median age was 38 years (range, 18–89), 53% were male, and 53% had an Ann Arbor stage I-II. Nodular sclerosis was the most common subtype (62%) and 23 of 115 available cases were EBV positive (20%). The International Prognostic Score (IPS) was 0–1 in 46% and 52% of GELA and MER patients, respectively. ABVD regimen was used for 60% and 88% of the GELA and MER patients, respectively. The 5-year progression free survival (PFS) was 83% and 75% in GELA and MER cohorts, respectively. We estimated the prognostic value of each individual SNP for PFS for allelic and genotypic (dominant and recessive) modes of transmission in each series. In order to increase power, we then performed a meta-analysis of the two studies. Results: Consistent with prior reports, the minor allele frequencies for REL (rs1432295), HLA-DRA (rs6903608), PVT1 (rs2608053), PVT1 (rs2019960), GATA3 (rs501764) and GATA3 (rs485411) were 0.44, 0.50, 0.43, 0.29, 0.22, 0.28 in the GELA and 0.46, 0.41, 0.46, 0.27, 0.25, 0.31 in the MER series, respectively. In GELA, GATA3 (rs501767) was associated with PFS in the ordinal model (HR=1.66, 95%CI 1.11–2.49, P=.01), while there were suggestive associations for PVT1 (rs2608053) (HR=1.76, 95%CI 0.95–3.26, P=.07) and REL (rs1432295) (HR=0.63, 95%CI 0.37–1.06, P=.08) in the dominant model. In the MER, PVT1 (rs2608053) was associated with PFS in the ordinal model (HR=1.42, 95%CI 0.99–2.03, P=.06), while there was a suggestive association with HLA-DRA (rs6903608) in the dominant model (HR=0.64, 95%CI 0.39–1.05, P=.08) for whole cohort but also for EBV negative cHL (HR=0.41, 95%CI 0.17–0.99, P=.05). In a meta-analysis of the two studies, PVT1 (rs2608053) was significantly associated with PFS in the ordinal (HR=1.34, 95%CI 1.04–1.73, P=.02) and the dominant (HR=1.88, 95%CI 1.20–2.95, P=.006) models. Further adjustment for IPS had minimal impact on these associations (ordinal HR=1.30, 95%CI 1.00–1.70; dominant HR=1.78, 95%CI 1.13–2.83). Patients with PVT1(rs2608053) GG, GA, AA genotypes had a 5-year PFS rate of 83%, 74% and 73% in GELA and 86%, 70%, and 73% in the MER, respectively. Conclusions: The non-HLA cHL susceptibility locus PVT1 (rs2608053) was associated with PFS in two independent cohorts of cHL cases, and after adjustment for the IPS. While associations with GATA3 and REL were only observed in one of the studies, their evaluation in other studies is warranted. Functional studies of PVT1 in cHL pathogenesis should be pursued. Disclosures: No relevant conflicts of interest to declare.

Abstract Abstract 440 Background: Complement plays a central role in innate immunity, and also functions as a regulator of the overall immune response, including T-cell responses. We recently reported that germline genetic variation in C2, C5, C7 and C9 was associated with risk of developing non-Hodgkin lymphoma (Br J Haematol 2009;145:614). Here we evaluate whether complement genes are associated with event-free survival (EFS) in follicular lymphoma. Methods: We genotyped 166 single nucleotide polymorphisms (SNPs) from 32 complement pathway genes in a prospective cohort study of 115 newly diagnosed follicular lymphoma patients enrolled at the Mayo Clinic from 2002-2005 as part of the Lymphoma SPORE. All patients were systematically followed through 2008 for EFS (defined as disease progression, retreatment, or death due to any cause). Tagging and nsSNPs were selected from HapMap for the genes encoding complement proteins and their key regulators (C1QB, C1QG, C1QR1, C1QTNF7, C1RL, C1S, C2, C3, C3AR1, C4BPA, C4BPB, C5, C5R1, C6, C7, C8B, C9, BF, CFH, CFHL5, CFHR1, CGHR4, CLU, CR1 (CD35), CR2 (CD21), DF, MASP2, MBL2, MCP (CD46), DAF (CD55), CD59 and SERPING1). Cox regression was used to estimate Hazard Ratios (HRs) for individual SNPs with EFS. The most prevalent homozygous genotype was used as the reference group, and each polymorphism was modeled individually as having a log-additive effect in the regression model. For gene-level analyses, we used a principal components based gene-level test. All models were adjusted for sex, FLIPI, follicular grade III, and initial treatment. Results. The median age at diagnosis was 61 years (range, 25-85). 57 (50%) of the patients had an event, at a median follow-up of 59 months (range, 33-73) for living patients. In gene-level analyses, CFH (p=0.004), CD55 (p=0.02), CFHR5 (p=0.02) and CFHR1 (p=0.02) were significant at p<0.05, and these genes had noteworthy q-values after consideration of multiple testing (q=0.04 for CFH and q=0.08 for CD55, CFHR5, and CFHR1). For CFH, 2 of the 11 tagSNPs (rs1329423, HR=0.46, p=0.001; and rs3766404, HR=2.0, p=0.003) were significantly associated with EFS, as was the nsSNP rs1065489 (amino acid change E936D: HR=0.39, p=0.004). For CD55, both tagSNPs (rs4844591, HR=0.58, p=0.03; and rs2564978, HR=0.58, p=0.03) were associated with EFS, as were 3 of 5 tagSNPs from CFHR5 (rs3748557, HR=0.52, p=0.03; rs12092294, HR=1.9, p=0.03; and rs6694672, HR=1.9, p=0.03) and the only tagSNP for CFHR1 (rs436719, HR=0.54, p=0.03). Conclusions. Genetic variation in CFH, CD55, CFHR5, and CFHR1 was associated with EFS in follicular lymphoma after adjustment for clinical variables. These genes are part of a gene cluster at 1q32-q32.1 involved in the regulation of C3. CD55 encodes a membrane complement regulatory protein which can allow tumor cells to evade complement attack. These results are being validated in a second set of SPORE patients. Support: P50 CA97274, R01 CA92153. Disclosures: No relevant conflicts of interest to declare.

Abstract Abstract 140 Background: Peripheral T-cell lymphomas (PTCLs) have poor outcomes, and there is a lack of prognostic biomarkers and therapeutic targets to guide treatment. We recently proposed that the transcription factor, interferon regulatory factor-4 (IRF4, also called multiple myeloma oncogene-1 [MUM1]), might be oncogenic in PTCLs based on its expression in association with translocations between IRF4 and the T-cell receptor gene, TRA@. IRF4 is a therapeutic target in multiple myeloma, where high expression is a poor prognostic factor. In addition, at least two germline IRF4 single nucleotide polymorphisms (SNPs), rs12203592 and rs872071, are associated with IRF4 expression and disease risk and progression in various lymphoid neoplasms. However, the prognostic effects of IRF4/MUM1 expression and IRF4 SNPs in PTCLs are unknown. Methods: Forty seven newly diagnosed PTCL patients with available tissue were identified from the University of Iowa/Mayo Clinic Lymphoma SPORE Molecular Epidemiology Resource. There were 5 anaplastic large cell lymphomas, 14 cutaneous T-cell lymphomas (CTCLs), 6 cytotoxic T-cell lymphomas (cytTCLs: 4 extranodal NK/T-cell and 2 enteropathy type), and 22 PTCLs, not otherwise specified (NOS). Patients were diagnosed between September 2002 and February 2008 and systematically followed through March 2010 for overall survival (OS). Tumor cell IRF4/MUM1 expression was examined by immunohistochemistry on paraffin tissue sections (MUM1p clone; Dako). Positivity was defined as >30% of tumor cells with nuclear staining, as in previous studies. rs12203592 and rs872071 were genotyped in peripheral blood DNA. Cox regression was used to estimate hazard ratios (HRs) and 95% confidence intervals (CIs) for both IRF4/MUM1 expression and SNPs with OS. Chi-squared tests were used to assess the relationship between IRF4/MUM1 expression and IRF4 SNPs. Results: The median age at diagnosis was 60 years (range, 24–88). At a median follow-up of 62 months (range, 29–89), 22 (47%) of the patients had died. Fifteen (32%) of the 47 T-cell patients had IRF4/MUM1 positive tumors. IRF4/MUM1 positivity was associated with poorer overall survival (HR=4.3; 95% CI: 1.8–10.2; p=0.0008). This association was seen across PTCL subtypes, including PTCL, NOS (HR= 6.5; 95% CI: 1.5–27.7; p=0.01), CTCL (HR=13.4; 95% CI: 1.2–150.1; p=0.03), and cytTCL (HR=5.8; CI: 0.5–65.9; p=0.15). The minor allele (T) in SNP rs12203592 was positively associated with IRF4/MUM1 positivity in a dominant model, with IRF4/MUM1 expression in 60% of patients with CT or TT genotypes compared to 19% of patients with CC genotype (p=0.01). Patients with the CT/TT genotype at rs12203592 also had inferior overall survival (HR=3.7; 95% CI: 1.4–9.5; p=0.007). The rs872071 SNP showed no significant association with either IRF4/MUM1 expression (p=0.38) or overall survival (p=0.71). Conclusions: This study is the first to demonstrate that IRF4/MUM1 expression is poor prognostic factor in PTCLs. This association was observed across PTCL subtypes, including the most common subtype, PTCL, NOS. IRF4/MUM1 expression and poor survival in our patients also were associated with the minor allele (T) in the IRF4 SNP rs12203592; these findings are consistent with previous in vitro data showing the major allele (C) represses IRF4 promoter activity. Interestingly, rs872071 was not associated with IRF4/MUM1 expression or prognosis, similar to findings in multiple myeloma. In contrast, rs872071 is a risk and prognostic factor in chronic lymphocytic leukemia and classical Hodgkin lymphoma, diseases in which IRF4/MUM1 expression has been associated with favorable prognosis. IRF4/MUM1 expression is a poor prognostic factor in PTCLs. Disclosures: No relevant conflicts of interest to declare.

AbstractBackgroundHuman pegivirus (HPgV) is a single-strand RNA virus belonging to the Flaviviridae. Although no definitive association between HPgV infection and disease has been identified, previous studies have suggested an association of HPgV viremia with risk of lymphomas.MethodsWe conducted a systematic review and meta-analysis, including 1 cohort study and 14 case-control studies, assessing the association of HPgV viremia with adult lymphomas. Odds ratios (ORs) and 95% confidence intervals (CIs) were calculated using a random-effects model, overall and by geographic region and lymphoma subtype.ResultsThe overall OR for lymphoma was 2.85 (95% CI, 1.98–4.11), with statistically significantly elevated ORs observed in 8 of 15 studies. There was a small amount of heterogeneity among studies (I2 = 28.9%; Q = 18.27, P = .16), and the funnel plot provided no evidence for publication bias. The strongest association with lymphoma risk was observed for studies from Southern Europe (OR, 5.68 [95% CI, 1.98–16.3]), whereas weaker ORs (with 95% CIs) were observed for studies from North America (2.24 [1.76–2.85]), Northern Europe (2.90 [.45–18.7), and the Middle East (2.51 [.87–7.27]), but all of similar magnitude. Participants with HPgV viremia had statistically significantly increased risks (OR [95% CI]) for developing diffuse large B-cell (3.29 [1.63–6.62]), follicular (3.01 [1.95–4.63]), marginal zone (1.90 [1.13–3.18]), and T-cell (2.11 [1.17–3.89]) lymphomas, while the risk for Hodgkin lymphoma (3.53 [.48–25.9]) and chronic lymphocytic leukemia (1.45 [.45–4.66]) were increased but did not achieve statistical significance.ConclusionsThis meta-analysis supports a positive association of HPgV viremia with lymphoma risk, overall and for the major lymphoma subtypes.

Abstract In this month's CME article, an analysis of over 1300 patients with diffuse large B-cell lymphoma (DLBCL), Wang et al demonstrate that the approximately 13% of patients with concurrent indolent lymphoma at diagnosis had the same prognosis as those patients with isolated DLBCL.

Background:Diffuse Large B Cell Lymphoma (DLBCL) is characterized by both biologic and genetic heterogeneity. While significant therapeutic advances have been made, nearly 30% of cases fail frontline treatment. Recent data suggest that 5–10% of DLBCL can be categorized as double/triple hit lymphoma (DH/TH), defined as having concurrent MYC, BCL2 and/or BCL6 gene rearrangements, identified by fluorescence in‐situ hybridization (FISH) probes. According to the 2017 revision of the World Health Organization classification of lymphoid neoplasms, DH/TH DLBCL is now considered a high grade B‐cell lymphoma (HGBL). While gene rearrangements represent significant genetic events in cancer, copy number alterations (CNAs) also play an important role, often through genomic amplification of oncogenes or loss of tumor suppressors. Despite their similarities, the contributions of CNAs in MYC, BCL2, and BCL6, alone, or in combination with gene rearrangements, are largely unknown in DLBCL and could identify a group of previously uncharacterized patients that may have high expression of MYC, BCL2 and/or BCL6 driven by alternative mechanisms.Aims:The goal of the study is to define the landscape and prognostic significance of gene rearrangements and copy gains in MYC, BCL2, and BCL6 in a cohort of newly diagnosed DLBCL.Methods:A total of 176 cases of DLBCL with both FISH and CNA data were available for the study. FISH was performed on formalin‐fixed paraffin‐embedded sections using break‐apart probes to MYC, BCL2, and BCL6 in the Mayo Clinic Department of Lab Medicine and Pathology. Somatic copy number alterations were identified using whole exome sequencing and the Affymetrix OncoScan® FFPE assay on patient tumor FFPE tissue, and were interrogated using Nexus Copy Number 9.0 software. All patients were treated with immunochemotherapy and prospectively followed for event‐free and overall survival.Results:FISH identified 3 groups of previously described patients, DH/TH or HGBL (n = 11), translocation positive (single MYC, BCL2, BLC6, or double BCL2/BLC6, n = 86), and translocation negative (n = 79). Expanding upon the translocation positive subgroup, copy number analysis identified patients (19 of 86, 22%) with copy number gains in a second or third gene resulting in genomic hits at both MYC and BCL2/6; we classified these as alternative‐double/triple‐hit (A‐DH/TH). An example of this would be a MYC translocation plus a BCL2 and/or BCL6 gain (n = 5), or a BCL2 and/or BCL6 translocation plus a copy gain in MYC (n = 14). Similar interrogation of a publically available dataset (n = 250), revealed similar proportions of these patient groups in an independent cohort of DLBCL, validating our findings. Cell of origin classification of the A‐DH/TH cases revealed that they were 53% GCB. A‐DH/TH patients, in comparison to the translocation‐positive/copy‐gain‐negative cases, were at greater risk of an event (Cox HR = 1.5, 95% CI = 0.71–3.0) and the cases trended towards a worse overall survival (log‐rank P = 0.065; Cox HR = 2.0, 95% CI = 0.94–4.3). Patients with copy‐gains alone had similar outcomes as those with no copy‐gain or translocations, suggesting a central role for at least one translocation event in predicting outcome.Summary/Conclusion:Our data suggest that use of CNA data in combination with traditional FISH can identify a unique subset of DLBCL, A‐DH/TH, that are missed by standard clinical practice. More importantly, we find that these patients do poorly and may benefit from more aggressive treatment, although we do acknowledge that our population size was small and further validation is needed.image

Background:Predicting early clinical failure in patients with untreated follicular lymphoma (FL) is important but difficult. Lymphoma involvement of extranodal (EN) sites is better detected by FDG‐PET/CT than CT alone, but PET parameters are not part of the usual predictive indices.Aims:We aimed to determine the incidence and patterns of EN and spleen disease, and learn if they were useful in predicting early clinical failure.Methods:PET/CT images from 613 cases of newly diagnosed FL between 2003 – 2016 were retrospectively reviewed for EN and spleen involvement. The location, number, and pattern of EN sites, as well as splenic involvement, were recorded. Associations with outcomes were assessed using event‐free survival (EFS), overall survival (OS), and early clinical failure at 24 months (EFS24).Results:49% (301/613) of patients had PET/CT‐detected EN involvement, and 28% (171/613) had spleen involvement. Presence of ≥2 EN sites, spleen, bone or soft tissue involvement all predicted failure to achieve EFS24. These factors, as well as pattern of bone involvement by imaging, were predictors of EFS on univariate analysis; presence of ≥2 EN sites and bone involvement pattern were also predictive of OS. In a multivariate analysis with FLIPI‐2 factors, spleen involvement, pattern of bone involvement, and soft tissue involvement independently predicted a lower EFS (Table 1). When the multivariate analysis was performed using PRIMA‐PI factors (marrow and B2 M), the presence of ≥2 EN sites was an adverse independent prognostic factor for OS (HR 2.28; 95% CI 1.01–5.18; p = 0.05).Table 1: Extranodal and spleen involvement by PET/CT as predictors of event‐free survival Summary/Conclusion:Baseline PET/CT identifies EN and spleen sites of disease that can predict early clinical failure in FL. These results, when combined with other factors, may better identify high‐risk patients and guide appropriate therapy.imageimage

Background:Recent large next generation sequencing studies have redefined the genomic landscape of diffuse large B‐cell lymphoma (DLBCL). While many of the more common genetic variants, primarily mutations, have been biologically characterized, little is known about newly emerging genetic aberrations. In particular, somatic copy number alterations remain poorly studied due to the large genomic regions they cover and the number of genes involved. This, in combination with lack of remission or early relapse in a portion of DLBCL, opens new opportunities to explore yet unidentified genetic contributions to lymphomagenesis.Aims:The goal of this study was to identify variants associated with failure to achieve event free survival at 24 months (EFS24) and define their biologic significance in DLBCL.Methods:Newly diagnosed DLBCL treated with standard immunochemotherapy were included in this study (n = 246). Copy number data was generated by using the molecular inversion probe OncoScan™ FFPE Assay Kit (Affymetrix, Santa Clara, CA, USA). OncoScan OSCHP files were analyzed using Nexus Copy Number 9.0 software (Biodiscovery, El Segundo, USA). Data interpretation and copy number calling was done using the human reference genome GRCh37/hg19. Files were analyzed using the Nexus FASST2‐Segmentation algorithm, which is based on a Hidden Markov Model approach for calling genetic events. For functional analysis, SOCS6 was overexpressed and studied in GCB‐DLBCL cell lines.Results:Upon review of genomic copy number data from DLBCL cases (n = 246), loss of 18q22.1‐q23 was a significant event in our cohort (p = 0.018), is found in 11% (n = 27) of DLBCL, and is enriched in germinal center DLBCL (GCB‐DLBCL) patients (18/107, 17%, p < 0.05) compared to activated B‐cell (ABC)/non‐GCB DLBCL patients (1/93, 1%). Furthermore, GCB‐DLBCL patients with a loss of 18q22.1‐q23 were significantly more likely to fail EFS24 (50%, p < 0.05) compared to GCB‐DLBCL patients without the loss (29%). Genes located at 18q22.1‐q23 include, TMX3, DOK6 and SOCS6. SOCS family proteins have been shown to play an important role in tumor biology, although little is known about SOCS6. SOCS6 gene expression is downregulated in a variety of solid tumors and is hypermethylated in some hematological malignancies. RNASeq data from DLBCL suggest variable expression across tumors. Using a panel of GCB cell lines we found that SOCS6 expression was low to negative, and publically available cell line data suggests this region is hypermethylated. Expression of SOCS6 was higher in a panel of mantle cell lymphoma and ABC‐DLBCL cell lines and this again correlated with their cell line methylation data, where no hypermethylation was found in those cell lines. Together, this data suggests that downregulation of SOCS6 through genomic loss or hypermethylation may have biologic importance. To explore the role of SOCS6, we restored expression in GCB cell lines and immuno‐fluorescence staining suggest localization to the nucleus and cytoplasm, as previously reported in other cell types. Studies to explore the role of SOCS6 in cytokine signaling and STAT family protein regulation are ongoing.Summary/Conclusion:Using genome copy number data from 246 DLBCL, we have found that loss of 18q22.1‐q23 (p = 0.018) is associated with GCB‐DLBCL and failure to achieve EFS24. Furthermore, we have identified that SOCS6 may have clinical and biologic significance in GCB‐DLBCL.