Lan, Qing

Introduction. Acquired severe aplastic anemia (SAA) is a life-threatening disorder characterized by severe progressive pancytopenia and hypocellular bone marrow. The etiology of acquired SAA is not understood but believed to be related to abnormal immune responses to environmental exposures. We conducted a genome-wide association study (GWAS) to identify common germline variants associated with SAA. Methods. We identified 895 patients with SAA who underwent related or unrelated hematopoietic cell transplant (HCT) with clinical data and pre-HCT blood samples available in the Center for International Blood and Marrow Transplant Research (CIBMTR) database and biorepository. Pre-HCT DNA was extracted from blood of patients with SAA and genome-wide genotyping was conducted using the Illumina OmniExpress array. We excluded 93 inherited bone marrow failure cases. The SAA cases were grouped cases into discovery and validation sets based on time of batch sample receipt. Analyses were limited to patients of European ancestry based on principal component analyses to minimize the potential effect of population stratification. Controls were genomically matched and selected from previously scanned cancer-free subjects at the Cancer Genomics Research Laboratory, Division of Cancer Epidemiology and Genetics, NCI. The final analysis included 534 acquired SAA cases (359 in the discovery set and 175 in the validation set), and 2,455 controls (1,396 in the discovery set, and 1,059 in the validation set). Results. Patients with SAA in this study received HCT between 1989-2015 at a median age of 21 years, 56% were male, and the median time between SAA diagnosis and HCT was 11 months. Strong genome-wide association signals were identified across the human leukocyte antigen (HLA) genes encoded at the major histocompatibility complex (MHC) on chromosome 6p21 (Figure 1). The top SNP was located in the P4 binding pocket of the HLA class II gene HLA-DPB1(rs1042151A>G, p.Met105Val, pooled-odds ratio [OR]=1.75, 95% confidence interval [CI]=1.50-2.03, p=1.94x10-13). The expression of HLA-DP in CD19+ cells from 175 healthy donors was significantly different by rs1042151 A>G genotype (p=2.04x10-6) (Figure 2). A second SNP near HLA-B, rs28367832G>A, also reached genome-wide significance (pooled-OR=1.49, 95% CI=1.22-1.78, p=7.27x10-9). Copy-number variant analysis and next generation sequencing also identified somatic, clonal copy-neutral loss-of-heterozygosity affecting class I HLA genes in 8.6% of the SAA cases and none of the controls. Conclusion. This SAA GWAS identified strong association signals between common germline genetic variants in HLA class I and II genes and SAA. The main SNP is associated with changes in HLA-DP expression suggesting a key role for this locus in SAA etiology. This study adds further evidence to the connection between SAA and immune dysregulation. Disclosures Cerhan: Janssen: Membership on an entity's Board of Directors or advisory committees; NanoString: Research Funding; Celgene: Research Funding. Lee:Incyte: Research Funding; Syndax: Research Funding; Amgen: Research Funding; Novartis: Research Funding; Takeda: Research Funding; Kadmon: Consultancy, Research Funding; Pfizer: Consultancy, Research Funding; AstraZeneca: Research Funding.

Abstract We previously identified five single nucleotide polymorphisms (SNPs) at four susceptibility loci for diffuse large B-cell lymphoma (DLBCL) in individuals of European ancestry through a large genome-wide association study (GWAS). To further elucidate genetic susceptibility to DLBCL, we sought to validate two loci at 3q13.33 and 3p24.1 that were suggestive in the original GWAS with additional genotyping. In the meta-analysis (5662 cases and 9237 controls) of the four original GWAS discovery scans and three replication studies, the 3q13.33 locus (rs9831894; minor allele frequency [MAF] = 0.40) was associated with DLBCL risk [odds ratio (OR) = 0.83, P = 3.62 × 10−13]. rs9831894 is in linkage disequilibrium (LD) with additional variants that are part of a super-enhancer that physically interacts with promoters of CD86 and ILDR1. In the meta-analysis (5510 cases and 12 817 controls) of the four GWAS discovery scans and four replication studies, the 3p24.1 locus (rs6773363; MAF = 0.45) was also associated with DLBCL risk (OR = 1.20, P = 2.31 × 10−12). This SNP is 29 426-bp upstream of the nearest gene EOMES and in LD with additional SNPs that are part of a highly lineage-specific and tumor-acquired super-enhancer that shows long-range interaction with AZI2 promoter. These loci provide additional evidence for the role of immune function in the etiology of DLBCL, the most common lymphoma subtype.

AbstractEpidemiologic 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.

Abstract A growing number of loci within the human leukocyte antigen (HLA) region have been implicated in non-Hodgkin lymphoma (NHL) etiology. Here, we test a complementary hypothesis of “heterozygote advantage” regarding the role of HLA and NHL, whereby HLA diversity is beneficial and homozygous HLA loci are associated with increased disease risk. HLA alleles at class I and II loci were imputed from genome-wide association studies (GWAS) using SNP2HLA for 3,617 diffuse large B-cell lymphomas (DLBCL), 2,686 follicular lymphomas (FL), 2,878 chronic lymphocytic leukemia/small lymphocytic lymphomas (CLL/SLL), 741 marginal zone lymphomas (MZL), and 8,753 controls of European descent. Both DLBCL and MZL risk were elevated with homozygosity at class I HLA-B and -C loci (OR DLBCL = 1.31, 95% CI = 1.06–1.60; OR MZL = 1.45, 95% CI = 1.12–1.89) and class II HLA-DRB1 locus (OR DLBCL = 2.10, 95% CI = 1.24–3.55; OR MZL = 2.10, 95% CI = 0.99–4.45). Increased FL risk was observed with the overall increase in number of homozygous HLA class II loci (P trend < 0.0001, FDR = 0.0005). These results support a role for HLA zygosity in NHL etiology and suggests that distinct immune pathways may underly the etiology of the different NHL subtypes. Significance: HLA gene diversity reduces risk for non-Hodgkin lymphoma. Cancer Res; 78(14); 4086–96. ©2018 AACR.

Objective Determinants of the increased risk of diffuse large B-cell lymphoma (DLBCL) in SLE are unclear. Using data from a recent lymphoma genome-wide association study (GWAS), we assessed whether certain lupus-related single nucleotide polymorphisms (SNPs) were also associated with DLBCL. Methods GWAS data on European Caucasians from the International Lymphoma Epidemiology Consortium (InterLymph) provided a total of 3857 DLBCL cases and 7666 general-population controls. Data were pooled in a random-effects meta-analysis. Results Among the 28 SLE-related SNPs investigated, the two most convincingly associated with risk of DLBCL included the CD40 SLE risk allele rs4810485 on chromosome 20q13 (OR per risk allele=1.09, 95% CI 1.02 to 1.16, p=0.0134), and the HLA SLE risk allele rs1270942 on chromosome 6p21.33 (OR per risk allele=1.17, 95% CI 1.01 to 1.36, p=0.0362). Of additional possible interest were rs2205960 and rs12537284. The rs2205960 SNP, related to a cytokine of the tumour necrosis factor superfamily TNFSF4, was associated with an OR per risk allele of 1.07, 95% CI 1.00 to 1.16, p=0.0549. The OR for the rs12537284 (chromosome 7q32, IRF5 gene) risk allele was 1.08, 95% CI 0.99 to 1.18, p=0.0765. Conclusions These data suggest several plausible genetic links between DLBCL and SLE.

Abstract Background: Diffuse large B-cell lymphoma (DLBCL) is the most common lymphoma subtype and is clinically aggressive. Relatives of DLBCL patients are at elevated risk for DLBCL. In small genome-wide association studies (GWAS) in which all NHL subtypes were combined, no conclusive loci for DLBCL have been previously identified in individuals of European background, whereas a recent study conducted in East Asia identified a locus at 3q27. Methods: To identify genetic susceptibility loci for DLBCL, we conducted a meta-analysis of three new GWAS and one prior scan, totaling 3,857 DLBCL cases and 7,666 controls of European ancestry. Imputation was used to combine all the data using the 1000 Genomes Project release v3 and IMPUTE2. Based on these findings, we selected 6 promising SNPs for genotyping in an additional 202 cases and 3,431 controls, which were then included in a second meta-analysis. SNPTEST was used to estimate odds ratios (ORs), using the additive model and adjusting for age, gender and significant eigenvectors. Results: In our multi-stage analysis, five independent SNPs in four loci achieved genome-wide significance marked by rs116446171 at 6p25.3 (EXOC2; OR=2.33, P=1.60x10-20), rs13255292 and rs4733601 at 8q24.21 (PVT1; OR=1.23, P=4.86x10-12 and OR=1.18, P=1.63x10-8, respectively), rs2523607 at 6p21.33 (HLA-B; OR=1.34, 3.35x10-9) and rs2681416 at 3q13.33 (CD86; OR=1.20, P=6.04x10-9). The two 8q24.21 SNPs displayed minimal linkage disequilibrium (r2=0.03) and conditional analysis supported their independence. We did not observe a notable signal for a locus previously reported for DLBCL on 3q27 in East Asia, rs6773854 (OR=1.06, P=0.81). We estimated that common SNPs, including but not limited to the loci discovered in this study, explain approximately 16% of the variance for DLBCL risk overall. Discussion: The susceptibility locus at 6p25.3 maps near a plausible DLBCL candidate gene, EXOC2 (exocyst complex component 2), which interacts with Ral proteins, and disruption of the Ral-exocyst regulatory node impacts cellular and developmental processes associated with malignant transformation and progression. The two 8q24.21 variants are approximately 1Mb telomeric to the 8q24 region linked with multiple cancers including CLL. Both variants are positioned in close proximity to PVT1, which is a non-coding RNA implicated in the MYC activation, and MYC is known to be deregulated in some DLBCLs. The locus at 3q13.33 maps to CD86 (B7-2), a B-7 family member that along with CD80 (B7-1) is essential in cognate interactions between T- and B-lymphocytes; both play key roles in immunodeficiency, autoimmune diseases, and in anti-tumor immunity. Finally, we had multiple signals in the HLA region, the strongest of which was at 6p21.33 near HLA-B. HLA-B encodes the HLA class I heavy chain paralogue, which heterodimerizes with a light chain (β2 microglobulin) and plays a central role in presenting intracellularly processed self or foreign antigens to CD8+ cytotoxic T lymphocytes. Class I molecules have been extensively linked to the risk of a variety of immune-mediated diseases and cancers including DLBCL. Conclusions: These data provide substantial new evidence for genetic susceptibility to this B-cell malignancy, and point towards pathways involved in immune recognition and immune function in the pathogenesis of DLBCL. Citation Format: James R. Cerhan, Sonja I. Berndt, Joseph Vijai, Hervé Ghesquières, James McKay, Sophia S. Wang, Zhaoming Wang, Meredith Yeager, Alexandra Nieters, David Cox, Alain Monnereau, Christopher Flowers, Anneclaire J. De Roos, Angela R. Brooks-Wilson, Qing Lan, Gianluca Severi, Mads Melbye, Rebecca D. Jackson, Lauren R. Teras, Mark Purdue, Claire Vajdic, Demetrius Albanes, Kimberly A. Bertrand, Anne Zeleniuch-Jacquotte, Simon Crouch, Yawei Zhang, Paolo Vineis, Susan L. Slager, Karin E. Smedby, Gilles Salles, Christine F. Skibola, Nathaniel Rothman, Stephen J. Chanock, on behalf of the NHL GWAS Project. Genome-wide association study identifies multiple susceptibility loci for diffuse large B-cell lymphoma. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr LB-272. doi:10.1158/1538-7445.AM2014-LB-272

Abstract Background. Follicular lymphoma (FL) is an indolent B-cell malignancy with a variable clinical course that may transform to more aggressive forms of lymphoma. Previous modestly powered GWAS have reported multiple FL susceptibility loci in the HLA class I and II regions at 6p21.32-33, but novel non-HLA susceptibility loci and the genetic architecture of FL associations in the HLA region remain to be elucidated. Methods. We conducted the largest GWAS of FL to date consisting of 2,142 cases and 6,221 controls of European ancestry from 22 studies scanned on the Illumina OmniExpress. After imputation of common SNPs using IMPUTE2 and 1,000 Genomes Project v3 data, we conducted a meta-analysis of these data with two previous FL GWAS (n=586 cases, 1,537 controls) and replicated top hits in an additional 629 cases and 4,283 controls. Expression quantitative trait loci (eQTL) analyses were performed to evaluate the effects of associated variants on gene expression. Classical HLA allele imputations and stepwise regression analyses are underway to further characterize the HLA associations. Results. In the joint meta-analysis, the strongest association with FL risk was observed in the HLA region, where a large number of SNPs showed genome-wide significance (P<5x10-8 to P= 1.84x10-84), particularly in HLA class II at 6p21.32 where several HLA eQTLs were identified (P < 0.05). Outside HLA, we identified four novel loci associated with FL at 11q23.3 (CXCR5, rs4938573; P=3.14x10-15), 11q24.3 (ETS1, rs4937362; P=3.33x10-9), 3q13.33 (CD86, rs2681416; P=9.79x10-11) and 3q28 (LPP, rs6444305, P=2.55x10-8). These novel susceptibility loci were located in four biologically relevant genes involved in immune regulation: CXCR5 and its ligand, CXCL13, are involved in guiding B-cells into the B-cell zones of secondary lymphoid organs as well as T-cell migration. ETS1 is expressed in lymphoid cells and regulates immune cell function including differentiation, survival, and proliferation. CD86 and CD80 are classic members of the B7 costimulatory pathway that is important in maintaining immune function, suppression of autoimmunity and antitumor surveillance. LPP encodes a LIM domain-containing protein of the zyxin family and participates in cell adhesion, cell migration, proliferation and transcription dynamics. Conclusions. This large GWAS provides further support for the important role of common genetic variation in non-HLA genes and further evidence of the key role that HLA immune-regulatory genes play in the pathogenesis of FL. Citation Format: Christine F. Skibola, Sonja I. Berndt, James R. Cerhan, Zhaoming Wang, Joseph Vijai, Lucia Conde, Paul de Bakker, Sophia S. Wang, Claire M. Vajdic, Brenda M. Birmann, Susan L. Slager, James McKay, Paige M. Bracci, Alexandra Nieters, Qing Lan, Angela R. Brooks-Wilson, Martha S. Linet, Demetrius Albanes, John J. Spinelli, Roel C.H. Vermeulen, Mark P. Purdue, Meredith Yaeger, Lauren R. Teras, Silvia de Sanjose, Alain Monnereau, Simon Crouch, Jia Nee Foo, Henrik Hjalgrim, Gianluca Severi, Brian K. Link, Kimberly A. Bertrand, Yawei Zhang, Karin E. Smedby, Stephen J. Chanock, Nathaniel Rothman, NHL GWAS Consortium. Meta-analysis of genome-wide association studies identifies novel susceptibility loci for follicular lymphoma. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 5072. doi:10.1158/1538-7445.AM2014-5072

Abstract Marginal zone lymphomas (MZL) are a group of indolent non-Hodgkin's B-cell lymphomas (NHL) comprising extranodal MZL of mucosa-associated lymphoid tissue (MALT) type, splenic MZL and nodal MZL. MZL comprises 7-12% of adult NHLs. The genetic etiology of MZL is poorly understood. To better understand the genetic risk factors for MZL, we conducted the first genome-wide association study (GWAS) of this lymphoid malignancy. The GWAS included 824 MZL cases and 6,220 controls of European ancestry from 22 studies of NHL. Genotyping was carried out at the Cancer Genomics Research Laboratory (CGR) of NCI using Illumina Human OmniExpress arrays. Standard genotyping quality controls were performed. Imputation of common SNPs was performed using IMPUTE2 software and 1000 Genomes Project release version 3 data. Association testing was subsequently performed using SNPTEST, assuming a log-additive genetic model adjusting for age, gender and three significant eigenvectors. We identified one locus at 6p21.32 within the HLA class II region that attained genome-wide significance (P<5x10-8). When a small number of additional cases (n=58) and controls (n=66) genotyped using Taqman assays were included, rs9461741 (BTNL2) was associated with an increased risk of MZL (per-allele odds ratio = 2.38, 95% confidence interval: 1.74-3.24; P=4.32x10-8). Other SNPs at the 6p21.32 locus were also highly associated with MZL, suggesting that this is unlikely to be a chance finding. Promising signals yet to be confirmed were also observed on chromosomes 3 and 14. The BTNL2 protein has extracellular immunoglobulin domains and is expressed in multiple tissues including various immune organs and the gut and it inhibits T-cell activation. Genetic variability at BTNL2 has been associated with inflammatory and infectious phenotypes, highlighting the importance of this locus for immune diseases. In conclusion, findings from this GWAS identify the HLA class II region as an important susceptibility locus for MZL. Citation Format: Joseph Vijai, Zhaoming Wang, Sonja I. Berndt, Susan L. Slager, James R. Cerhan, Christine Skibola, Sophia S. Wang, Angela R. Brooks-Wilson, Silvia de Sanjose, Paige M. Bracci, Mads Melbye, Bengt Glimelius, Rebecca D. Jackson, Wendy Cozen, Nikolaus Becker, Lauren R. Teras, John J. Spinelli, Jenny Turner, Qing Lan, Mark P. Purdue, Kimberly A. Bertrand, Kenneth Offit, Paolo Vineis, Brian K. Link, Graham G. Giles, Anne Zelenuich-Jacquotte, Alain Monnereau, Maria Grazia Ennas, Demetrius Albanes, Laurie Burdett, Nathaniel Rothman, Stephen J. Chanock, Alexandra Nieters, On behalf of the NHL GWAS Consortium. A genome-wide association study suggests evidence of variants at 6p21.32 associated with marginal zone lymphoma. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 5071. doi:10.1158/1538-7445.AM2014-5071

AbstractObjectivesDiffuse large B‐cell lymphoma (DLBCL) is an aggressive subtype of non‐Hodgkin lymphoma (NHL) and is the most common NHL subtype diagnosed worldwide. The first large‐scale genome‐wide association study (GWAS) of DLBCL with over 4000 cases conducted among individuals of European ancestry recently identified five independent SNPs that achieved genome‐wide significance, and two SNPs that showed a suggestive association with DLBCL risk.MethodsTo evaluate whether Eastern Asians and individuals of European ancestry share similar genetic risk factors for this disease, we attempted to replicate these GWAS findings in a pooled series of 1124 DLBCL cases and 3596 controls from Hong Kong, South Korea, and Thailand.ResultsThree of the five genome‐wide significant SNPs from the DLBCL GWAS were significantly associated with DLBCL in our study population, including the top finding from the GWAS, EXOC2 rs116446171, which achieved genome‐wide significance in our data (per allele OR = 2.04, 95% CI = 1.63–2.56; ptrend = 3.9 × 10−10). Additionally, we observed a significant association with PVT1 rs13255292 (per allele OR = 1.34, 95% CI = 1.19–1.52; ptrend = 2.1 × 10−6), which was the second strongest finding in the GWAS, and with HLA‐B rs2523607 (per allele OR = 3.05, 95% CI = 1.32–7.05; ptrend = 0.009).ConclusionsOur study, which provides the first evaluation in Eastern Asians of SNPs definitively associated with DLBCL risk in individuals of European ancestry, indicates that at least some of the genetic factors associated with risk of DLBCL are similar between these populations.