Polygenic Risk Score and Risk of Chronic Lymphocytic Leukemia, Monoclonal B-Cell Lymphocytosis (MBL), and MBL Subtypes

Blood ◽  
2020 ◽  
Vol 136 (Supplement 1) ◽  
pp. 35-36
Author(s):  
Geffen Kleinstern ◽  
J. Brice Weinberg ◽  
Sameer A. Parikh ◽  
Esteban Braggio ◽  
Dennis P. Robinson ◽  
...  

Background MBL is a precursor to chronic lymphocytic leukemia (CLL) and is subclassified into low-count (LC) MBL (absolute B-cell count<0.5x109/L) and high-count (HC) MBL (absolute B-cell count between 0.5 and 5x109/L). We previously reported that a polygenic risk score (PRS) based on a weighted average of 41 CLL-susceptibility variants was associated with risk of both MBL and CLL among a cohort of individuals from CLL families. Here we evaluate this PRS in an independent cohort of MBL and CLL individuals of European ancestry (EA), all of whom were ascertained agnostic to CLL family-history status. We also evaluate the PRS by MBL subtype (LC/HC), and in African American (AA) CLL cases and controls. Methods We genotyped 535 EA MBLs (139 HC-MBL, 396 LC-MBLs), 735 CLLs (640 EA, 95 AA), and 2,866 controls (2,631 EA, 235 AA) from the Mayo Clinic CLL Resource, Duke University, and Weill Cornell Medical College. We computed the CLL-PRS for each individual and used logistic regression to estimate odds ratios (OR) and 95% confidence intervals, adjusting for age and sex. To assess discriminatory accuracy, we computed the c-statistic. Among EA individuals, we calculated a trend test among LC-MBL, HC-MBL, and CLL risk using the P-value for heterogeneity from a polytomous logistic regression analysis. Moreover, we plotted a boxplot for the PRS among controls, LC-MBL, HC-MBL, and EA CLL, as well as for AA CLL cases and controls, and tested the statistical difference using the Kruskal Wallis test and Mann-Whitney test, respectively. Results We found a significant association of PRS with overall MBL risk (OR=1.87, P=1.1x10-28) with good discrimination (c-statistic=0.72). Significant associations were also found for LC-MBL (OR=1.75, P=7.5x10-19, c-statistic=0.72), HC-MBL (OR=2.22, P=1.4x10-17, c-statistic=0.74), and CLL of EA (OR=2.60, P=1.2x10-62, c-statistic=0.78), with a significant difference among these cohorts (Figure 1.A) and a significant positive trend across these cohorts (Pheterogeneity=8.4x10-6). Although we observed a 33% increased risk of CLL in AA (c-statistic=0.57), the PRS was borderline significant (P=0.07, Figure 1.B). Conclusion The CLL-PRS is a strong prediction-tool for risk of CLL and MBL among individuals of EA. Future studies are needed to improve the PRS for AAs including performing GWAS of AA in order to identify CLL-susceptibility SNPs that are more representative within known CLL loci and to discover novel CLL loci that are unique for AAs. Disclosures Parikh: GlaxoSmithKline: Honoraria; Janssen: Honoraria, Research Funding; Ascentage Pharma: Research Funding; AbbVie: Honoraria, Research Funding; Merck: Research Funding; TG Therapeutics: Research Funding; Genentech: Honoraria; Pharmacyclics: Honoraria, Research Funding; MorphoSys: Research Funding; AstraZeneca: Honoraria, Research Funding; Verastem Oncology: Honoraria. Braggio:DASA: Consultancy; Bayer: Other: Stock Owner; Acerta Pharma: Research Funding. Brander:Genentech: Consultancy, Honoraria, Other, Research Funding; Juno/Celgene/BMS: Other, Research Funding; MEI Pharma: Other, Research Funding; Ascentage: Other, Research Funding; ArQule: Consultancy, Other, Research Funding; NCCN: Other; Teva: Consultancy, Honoraria; Tolero: Research Funding; AstraZeneca: Consultancy, Honoraria, Other, Research Funding; Pharmacyclics LLC, an AbbVie Company: Consultancy, Honoraria, Other, Research Funding; Pfizer: Consultancy, Other; TG Therapeutics: Consultancy, Membership on an entity's Board of Directors or advisory committees, Other, Research Funding; Novartis: Consultancy, Other; AbbVie: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Other, Research Funding; Tolero: Research Funding; Teva: Consultancy, Honoraria; DTRM: Other, Research Funding; BeiGene: Other, Research Funding; Novartis: Consultancy, Other; NCCN: Other; Verastem: Consultancy, Honoraria, Other, Research Funding. Cerhan:NanoString: Research Funding; BMS/Celgene: Research Funding. Kay:Astra Zeneca: Membership on an entity's Board of Directors or advisory committees; Agios Pharma: Membership on an entity's Board of Directors or advisory committees; Sunesis: Research Funding; Pharmacyclics: Membership on an entity's Board of Directors or advisory committees, Research Funding; Acerta Pharma: Research Funding; Juno Theraputics: Membership on an entity's Board of Directors or advisory committees; Morpho-sys: Membership on an entity's Board of Directors or advisory committees; Rigel: Membership on an entity's Board of Directors or advisory committees; Cytomx: Membership on an entity's Board of Directors or advisory committees; Tolero Pharmaceuticals: Membership on an entity's Board of Directors or advisory committees, Research Funding; Bristol Meyer Squib: Membership on an entity's Board of Directors or advisory committees, Research Funding; MEI Pharma: Research Funding; Abbvie: Research Funding; Oncotracker: Membership on an entity's Board of Directors or advisory committees; Dava Oncology: Membership on an entity's Board of Directors or advisory committees. Furman:Acerta: Consultancy; AstraZeneca: Consultancy, Research Funding; Beigene: Consultancy; Abbvie: Consultancy; Pharmacyclics: Consultancy; Sunesis: Consultancy; TG Therapeutics: Consultancy, Research Funding; Verastem: Consultancy; Incyte: Consultancy; Genentech: Consultancy; Janssen: Consultancy, Speakers Bureau; Loxo Oncology: Consultancy; Oncotarget: Consultancy. Shanafelt:Mayo Clinic: Patents & Royalties: and other intellectual property; Genentech, Pharmacyclics LLC, an AbbVie Company, AbbVie, GlaxoSmithKline, and Merck: Research Funding.

Blood ◽  
2020 ◽  
Vol 136 (Supplement 1) ◽  
pp. 9-9
Author(s):  
Shanye Yin ◽  
Gregory Lazarian ◽  
Elisa Ten Hacken ◽  
Tomasz Sewastianik ◽  
Satyen Gohil ◽  
...  

A hotspot mutation within the DNA-binding domain of IKZF3 (IKZF3-L162R) has been identified as a putative driver in chronic lymphocytic leukemia (CLL); however, its functional effects are unknown. We recently confirmed its role as a CLL driver in a B cell-restricted conditional knock-in model. IKZF3 mutation altered mature B cell development and signaling capacity, and induced CLL-like disease in elderly mice (~40% penetrance). Moreover, we found IKZF3-L162R acts as a gain-of-function mutation, altering DNA binding specificity and target selection of IKZF3, and resulting in overexpression of multiple B-cell receptor (BCR) genes. Consistent with the murine data, RNA-sequencing analysis showed that human CLL cells with mut-IKZF3 [n=4] have an enhanced signature of BCR-signaling gene expression compared to WT-IKZF3 [n=6, all IGHV unmutated] (p<0.001), and also exhibited general upregulation of key BCR-signaling regulators. These results confirm the role of IKZF3 as a master regulator of BCR-signaling gene expression, with the mutation contributing to overexpression of these genes. While mutation in IKZF3 has a clear functional impact on a cardinal CLL-associated pathway, such as BCR signaling, we note that this driver occurs only at low frequency in patients (~3%). Because somatic mutation represents but one mechanism by which a driver can alter a cellular pathway, we examined whether aberrant expression of IKZF3 could also yield differences in BCR-signaling gene expression. We have observed expression of the IKZF3 gene to be variably dysregulated amongst CLL patients through re-analysis of transcriptomic data from two independent cohorts of human CLL (DFCI, Landau et al., 2014; ICGC, Ferreira et al., 2014). We thus examined IKZF3 expression and BCR-signaling gene expression, or the 'BCR score' (calculated as the mean expression of 75 BCR signaling-associate genes) in those cohorts (DFCI cohort, n=107; ICGC cohort, n=274). Strikingly, CLL cells with higher IKZF3 expression (defined as greater than median expression) had higher BCR scores than those with lower IKZF3 expression (<median) (p=0.0015 and p<0.0001, respectively). These findings were consistent with the notion that IKZF3 may act as a broad regulator of BCR signaling genes, and that IKZF3 overexpression, like IKZF3 mutation, may provide fitness advantage. In support of this notion, our re-analysis of a gene expression dataset of 107 CLL samples (Herold Leukemia 2011) revealed that higher IKZF3 expression associated with poorer prognosis and worse overall survival (P=0.035). We previously reported that CLL cells with IKZF3 mutation appeared to increase in cancer cell fraction (CCF) with resistance to fludarabine-based chemotherapy (Landau Nature 2015). Instances of increase in mut-IKZF3 CCF upon treatment with the BCR-signaling inhibitor ibrutinib have been reported (Ahn ASH 2019). These studies together suggest an association of IKZF3 mutation with increased cellular survival following either chemotherapy or targeted treatment. To examine whether higher expression of IKZF3 was associated with altered sensitivity to ibrutinib, we performed scRNA-seq analysis (10x Genomics) of two previously treatment-naïve patients undergoing ibrutinib therapy (paired samples, baseline vs. Day 220). We analyzed an average of 11,080 cells per patient (2000 genes/cell). Of note, following ibrutinib treatment, remaining CLL cells expressed higher levels of IKZF3 transcript compared to pretreatment baseline (both p<0.0001), whereas no such change was observed in matched T cells (n ranging between 62 to 652 per experimental group, p>0.05), suggesting that cells with high expression of IKZF3 were selected by ibrutinib treatment. Moreover, we showed that ibrutinib treatment resulted in consistent upregulation of BCR-signaling genes (e.g., CD79B, LYN, GRB2, FOS, RAC1, PRKCB and NFKBIA) (n ranging between 362 to 1374 per experimental group, all p<0.0001), which were likewise activated by mutant IKZF3. Altogether, these data imply that IKZF3 mutation or overexpression may influence upregulation of BCR-signaling genes and enhance cellular fitness even during treatment with BCR-signaling inhibitors. We highlight our observation that IKZF3 mutation appears to be phenocopied by elevated IKZF3 expression, and suggest that alterations in mRNA or protein level that mimic genetic mutations could be widespread in human cancers. Disclosures Kipps: Pharmacyclics/ AbbVie, Breast Cancer Research Foundation, MD Anderson Cancer Center, Oncternal Therapeutics, Inc., Specialized Center of Research (SCOR) - The Leukemia and Lymphoma Society (LLS), California Institute for Regenerative Medicine (CIRM): Membership on an entity's Board of Directors or advisory committees, Research Funding, Speakers Bureau; Celgene: Honoraria, Research Funding; Gilead: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Genentech/Roche: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; VelosBio: Research Funding; Oncternal Therapeutics, Inc.: Other: Cirmtuzumab was developed by Thomas J. Kipps in the Thomas J. Kipps laboratory and licensed by the University of California to Oncternal Therapeutics, Inc., which provided stock options and research funding to the Thomas J. Kipps laboratory, Research Funding; Ascerta/AstraZeneca, Celgene, Genentech/F. Hoffmann-La Roche, Gilead, Janssen, Loxo Oncology, Octernal Therapeutics, Pharmacyclics/AbbVie, TG Therapeutics, VelosBio, and Verastem: Membership on an entity's Board of Directors or advisory committees. Wu:BionTech: Current equity holder in publicly-traded company; Pharmacyclics: Research Funding.


Blood ◽  
2011 ◽  
Vol 118 (21) ◽  
pp. 288-288 ◽  
Author(s):  
Matthew Kaufman ◽  
Xiao J. Yan ◽  
Emanuela M. Ghia ◽  
Donna Neuberg ◽  
Laura Z. Rassenti ◽  
...  

Abstract Abstract 288 BACKGROUND. Chronic lymphocytic leukemia (CLL) patients with mutated IGHV genes (M-CLL) have better outcomes than patients with unmutated IGHV genes (U-CLL). It has been proposed that this difference reflects the fact that IGHV mutations alter the structure of the B-cell antigen receptor (BCR) such that it no longer binds stimulatory (auto) antigens and therefore cannot deliver trophic signals to the leukemic cells. For this theory to be correct, only replacement (R) mutations and in particular non-conservative R mutations that would more likely alter amino structure of the IGHV/D/J rearrangements would have relevance. Silent (S) mutations by definition do not change amino acid structure and could not alter antigen binding. We sought to investigate this hypothesis by analyzing the types (S, conservative R, non-conservative R) and distribution of mutations that occur in IGHVs of M-CLL clones and then comparing the time to first therapy (TTFT) in patients with different IGHV features. This analysis expanded an initial study of 1569 CLL cases in the US to include 1858 patients from Europe for a total of 3427 cases. METHODS. Using IGMT software and tools, we analyzed the rearranged IGHV sequences of 3427 cases and characterized their mutations in several respects: first, if IGHV mutations altered amino acid structure (S vs. R); second, if mutations occurred in CDRs (antigen binding domains) or FRs (scaffolds of the BCR); third, if R mutations were conservative or non-conservative as determined by charge, hydropathy, and size. TTFT for patients was examined with various combinations of the above parameters. Differences in TTFT were estimated by the method of Kaplan and Meier and assessed using the log rank test. RESULTS. First, TTFT was compared for 4 groups of patients with the following mutation profiles: no mutations; only S mutations (median 1 per sample); only R mutations (median 1 per sample); and mixed S and R mutations (median 16 per sample). These 4 categories were significantly different (P<0.0001), with the median TTFT being 2.0 yrs for no mutations; 2.6 yrs for R only; 2.8 yrs for S only; and 7.3 yrs for mixed. All comparisons used patients with no mutations (n=1234) as the reference group. We identified statistically longer TTFT (2.8 vs 2.0 yrs; P=0.04) in patients with only S mutations (n=62). Patients with only R mutations (n=218) also had superior outcomes (2.6 yrs vs. 2.0 yrs; P=0.008). There was no statistical significance in TTFT between patients with all S vs. all R mutations (2.8 yrs vs. 2.6 yrs; P=0.71). Because exploring the relevance of BCR structural change on TTFT required us to focus on a small subset of patients with only silent IGHV mutations, our sample size was small. Therefore, we expanded the group to include IGHVs with R mutations limited to the FR region (S + R in FR only; n=241) since these mutations would be unlikely to have a major impact on BCR structure, particularly sparing the binding site. When compared to patients with no mutations, this group demonstrated a significantly longer TTFT (2.8 yrs vs. 2.0 yrs, P=0.0002). This finding was upheld when not permitting any non-conservative R mutations in this group, leaving only patients with S plus conservative R mutations in FRs only (n=124); TTFT in this case was 2.8 yrs vs. 2.0 yrs, respectively (P=0.0006). CONCLUSIONS. Our findings show that patients with only S mutations have better outcomes than patients with no mutations, suggesting that a change in BCR structure that could lead to a loss of antigen binding is an unlikely reason for improved clinical course. This is further supported by the finding that the combination of only S plus conservative R mutations located solely in FRs, which probably would not result in major BCR structural changes and therefore antigen binding, is associated with a lengthened TTFT. Therefore, we suggest that the currently accepted paradigm to explain the enhanced survival of M-CLL patients needs to be re-evaluated. Disclosures: Brown: Calistoga: Consultancy, Research Funding; Celgene: Honoraria, Research Funding; Genzyme: Research Funding; GSK: Research Funding. Kipps:Igenica: Equity Ownership, Membership on an entity's Board of Directors or advisory committees; Celgene: Consultancy, Research Funding; Abbott Industries: Research Funding; Pharmacyclics: Membership on an entity's Board of Directors or advisory committees; Genentech: Research Funding; GSK: Research Funding; Gilead Sciences: Consultancy, Research Funding; Amgen: Research Funding.


Blood ◽  
2019 ◽  
Vol 134 (Supplement_1) ◽  
pp. 5457-5457
Author(s):  
Anna Puiggros ◽  
Gonzalo Blanco ◽  
Aura Muntasell ◽  
María Rodríguez-Rivera ◽  
Lara Nonell ◽  
...  

Background. Dysregulated NK-cell responses have been reported in chronic lymphocytic leukemia (CLL) patients, but little is known about the NK cell compartment in CLL-like monoclonal B cell lymphocytosis (MBL). Human cytomegalovirus (HCMV) infection induces an adaptive reconfiguration of the NK cell compartment characterized by the differentiation and persistent expansion of a subset displaying the CD94/NKG2C NK receptor (NKR). Moreover, a deletion of the NKG2C (KLRC2) gene has been reported to modulate the magnitude of the NK cell repertoire redistribution. Little is known about the expression of NKG2C in CLL and MBL patients. Aims. To analyse the distribution of NKR, with special attention to NKG2C, in MBL and CLL patients, assessing the relation of the NK cell immunophenotype with clinical features. Methods. The study cohort included 61 patients, 24 were diagnosed with clinical MBL and 37 were treatment-naïve CLL (32/37 Binet A). The expression of NKG2C, NKG2A, ILT2 (LIR1, LILRB1), CD161, CD57 and KIRs (identified with a cocktail of monoclonal antibodies) was assessed by flow cytometry in peripheral blood NK cells. The NKG2C (KLRC2) genotype was analysed in a larger representative MBL/CLL cohort (n=135). Results. The proportions of NK cells were reduced in CLL patients compared to MBL (median 5.5% vs. 10%; P=0.003), whereas their absolute numbers were increased (median 0.85x109/L vs. 0.57x109/L; P=0.002). No significant differences between MBL and CLL were detected regarding the distribution of the different NKR: NKG2C (median: 2.7 vs. 5.9%, respectively), NKG2A (31.4 vs. 30.8%), ILT2 (18.0 vs.15.8%), KIRs (54.4 vs. 52.7%), CD161 (16.1 vs. 16.4%) and CD57 (40.4 vs. 38.9%). Though a reduced NKG2C expression was noticed in both entities, it was specially marked in patients with a greater (>30x109 cells/L) lymphocytosis (1.4 vs. 7.7%, P=0.016). The proportions of NKG2C+ NK cells in HCMV+ patients (85%, 47/55) as compared to HCMV- individuals were not significantly different (6.3% vs. 2.9%, respectively). HCMV+ patients showed a significantly lower NKG2C expression when compared with two independent age-matched cohorts of HCMV+ non-CLL/-MBL individuals, including 43 non-metastatic breast cancer patients (4.2% vs. 15.3% , P<0.001); and 30 renal transplantation donors (4.2% vs.12.4% in P=0.028). The frequencies of NKG2C+/+ (56%), NKG2C+/del (37%) and NKG2Cdel/del (7%) genotypes were comparable to those previously defined in healthy blood donors. Moreover, cases with very low (<2%) or undetectable NKG2C expression were found in NKG2Cdel/del patients (100%, 6/6), but also among NKG2C+/- (45%, 10/22) and NKG2C+/+ (12%, 3/26) genotypes. Conclusions. 1. MBL and CLL exhibited low proportions of NKG2C+ NK cells. This immunophenotype was particularly evident in CLL patients with increased lymphocytosis and could not be explained by differences in HCMV seropositivity, NKG2C zygosity nor age. 2. Additional studies are required to define the mechanism(s) and putative implications of the reduced NKG2C expression in these lymphoproliferative disorders. Acknowledgements. PI11/1621; PI15/437; 2017/SGR437; Fundació La Caixa; Fundación Española de Hematología y Hemoterapia (FEHH). Disclosures Gimeno: JANSSEN: Consultancy, Speakers Bureau; Abbvie: Speakers Bureau. Abrisqueta:Celgene: Consultancy, Honoraria; Abbvie: Consultancy, Honoraria, Other: Travel, Accommodations, expenses, Speakers Bureau; Janssen: Consultancy, Honoraria, Other: Travel, Accommodations, expenses, Speakers Bureau; Roche: Consultancy, Honoraria, Other: Travel, Accommodations, expenses, Speakers Bureau. Bosch:Novartis: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding, Speakers Bureau; Janssen: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding, Speakers Bureau; Kyte: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding, Speakers Bureau; Acerta: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding, Speakers Bureau; Celgene: Honoraria, Research Funding; AbbVie: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding, Speakers Bureau; F. Hoffmann-La Roche Ltd/Genentech, Inc.: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding, Speakers Bureau; Takeda: Honoraria, Research Funding; AstraZeneca: Honoraria, Research Funding.


Blood ◽  
2019 ◽  
Vol 134 (Supplement_1) ◽  
pp. 5454-5454 ◽  
Author(s):  
Francesca Arruga ◽  
Giulia Guerra ◽  
Denis Baev ◽  
Catherine Hoofd ◽  
Marta Coscia ◽  
...  

Introduction: T cell immunoreceptor with Ig and ITIM domains (TIGIT) is a surface receptor mainly expressed by CD8+, regulatory T lymphocytes and natural killer (NK) cells, but not by normal B cells. It performs as an inhibitory immune checkpoint, activated through binding of CD155. TIGIT competes with CD226 for CD155 binding, resulting in opposite outcomes: while CD226 enhances cytotoxicity of T lymphocytes and NK cells, TIGIT exerts immunosuppressive effects. Whether TIGIT engagement triggers an alternative signaling cascade, or whether it simply prevents CD226 activation, remains an open point. Tumor-infiltrating T lymphocytes generally express high levels of the molecule, together with the other checkpoint inhibitor PD-1. On this basis, antagonist antibodies targeting TIGIT are under evaluation to restore immunity and treat cancer patients, alone or in various combinations. Chronic lymphocytic leukemia (CLL), the most common adult leukemia, is characterized by a highly heterogeneous clinical outcome. Several molecular markers can help in stratifying patients, including the presence or absence of somatic mutations in B cell receptor, cytogenetic aberrations and single gene mutations. Interestingly, CLL cells express several T cell specific antigens, including CD5. A previous report indicates that, in CLL, TIGIT is expressed by circulating CD4+T cells, increasing during disease progression, while nothing is known about its expression on CLL cells. Aim:This work was undertaken with the aim of studying expression of the TIGIT/CD226/CD155 axis in CLL. Methods:We assembled a cohort of 101 primary CLL samples (40% females, mean age of 61). All patients were either untreated or had not received treatment in the 6 months prior to analysis. PBMC samples were tested for expression of TIGIT, CD155 and CD226 in both T and B subsets. A multiparametric flow cytometry strategy was designed, combining anti-TIGIT, anti-CD155 and anti-CD226 antibodies with a panel of B- (anti-CD19, anti-CD5, anti-CD38, anti-CD49d and anti-CD73) and T-mono/NK specific (anti-CD3, anti-CD8, anti-CD4, anti-CD14 and anti-CD56) markers. The number of TIGIT molecules on leukemic cells was estimated by interpolating values of mean fluorescence intensity (MFI) of each sample with that of PE-Quantibrite beads. Results:CLL cells heterogeneously express surface TIGIT, ranging from 0.2 to 81% (mean value 20%, median 10%, SEM ±2.145). The estimated number of molecules per cell was in the range of 32.5-3571 (mean 1140, median 841.1, SEM ±83.6). Expression of TIGIT was independent of gender or age at diagnosis and there was no correlation between TIGIT levels and lymphocyte counts in peripheral blood. In contrast, in this cohort of untreated patients, we observed a significantly lower TIGIT expression in samples with advanced disease (RAI III-IV) compared to early stages (RAI 0-I). Accordingly, low TIGIT associated with unmutated (UM) IGHVgenes and with an unfavorable FISH profile (trisomy 12, deletion 17 and deletion 11 vs. deletion 13 or normal karyotype). Lower, although not significant, TIGIT levels were observed in NOTCH1-mutated CLL samples (n=11) compared to counterpart (n=89). Looking at the T cell population, we observed overall higher TIGIT levels in the CD8+vs CD4+subset (mean %TIGIT+cells in CD8+56.7±1.8 vs 27.2±1.3 in CD4+). In line with reported observations, we found a modest but significant increase of TIGIT+T cells in advanced stage CLLs, at variance with what observed on the leukemic B cell side. Accordingly, we observed higher percentages of TIGIT+/CD4+cells in CLL samples carrying UM IGHVgenes. CD226 and CD155 were more homogeneously expressed in all subsets without significant differences, both in CLL and T cell components. Conclusions: This work shows that CLL cells express the immunomodulatory molecule TIGIT, particularly in the early stages of the disease in untreated patients. While further studies are needed to characterize its functional implications as well as treatment effect on TIGIT expression, it is tempting to speculate that TIGIT expression by CLL cells may serve to trigger an immunosuppressive behavior in these cells, which is no longer needed when the disease becomes advanced. This observation represents a starting point for future studies investigating the role of TIGIT in CLL and hints to a possible use of anti-TIGIT antibodies to target different cellular components of the disease. Disclosures Hoofd: iTeos Therapeutics: Employment. Coscia:Abbvie: Membership on an entity's Board of Directors or advisory committees; Gilead: Membership on an entity's Board of Directors or advisory committees; Janssen: Membership on an entity's Board of Directors or advisory committees, Research Funding; Karyopharm Therapeutics: Research Funding. Gaidano:Sunesys: Consultancy, Honoraria; AbbVie: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Astra-Zeneca: Consultancy, Honoraria; Janssen: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau. Furman:Acerta Pharma: Consultancy; Beigene: Consultancy; Incyte: Consultancy; Janssen: Consultancy; Oncotracker: Consultancy; Pharmacyclics: Consultancy; Sunesis: Consultancy; TG Therapeutics: Consultancy; Verastem: Consultancy; Genentech: Consultancy; Abbvie: Consultancy; AstraZeneca: Consultancy. Deaglio:VelosBio Inc.: Research Funding; Verastem Inc: Research Funding; iTeos Therapeutics: Research Funding.


Blood ◽  
2011 ◽  
Vol 118 (21) ◽  
pp. 1793-1793 ◽  
Author(s):  
William G. Wierda ◽  
Roxanne C. Jewell ◽  
Thomas J. Kipps ◽  
Jan Dürig ◽  
Laimonas Griskevicius ◽  
...  

Abstract Abstract 1793 Introduction: Results: Seven pts (4 male) with a medianLittle is known about the pharmacokinetics (PK) and pharmacodynamics of CD20 monoclonal antibody (mAb) with chemotherapy in patients (pts) with CLL. Ofatumumab (O) is a human mAb targeting a membrane-proximal small-loop epitope on CD20 and mediates efficient complement-dependent cytotoxicity and antibody-dependent cell-mediated cytotoxicity. Safety and efficacy of O at 2 dose levels in combination with fludarabine and cyclophosphamide (FC) were evaluated in previously untreated pts with CLL. Relationship between O PK, baseline characteristics, and clinical outcomes were studied. Pts and Methods: Pts with active CLL were randomized to O 500 mg (n=31) or 1000 mg (n=30) on Day 1 with F 25 mg/m2 and C 250 mg/m2 on Days 2–4 (Course 1) or Days 1–3 (Courses 2–6) every 4 weeks for 6 courses. O dose at Course 1 was 300 mg for both groups. Response (1996 NCI-WG criteria) was assessed by an Independent Review Committee up to 3 months after last course. Serial blood samples were collected at Courses 1 and 6 for noncompartmental PK analyses; pre- and post-infusion samples were collected at other courses. Relationship between PK parameters and baseline pt characteristics and disease factors was evaluated by univariable and multivariable analyses. Associations between PK and complete response (CR), overall response (OR), or progression-free survival (PFS) were explored using univariable regression analyses. Results: 22/31 (71%; 500 mg) and 19/30 (63%; 1000 mg) of pts received all 6 O doses; 2 pts at 1000 mg did not receive FC for Course 6. CR (primary endpoint) rates of 32% and 50% and OR rates of 77% and 73% were observed in the 500 mg and 1000 mg groups, respectively. O PK parameters are summarized (Table). O PK at Dose 6 appeared proportional to dose. Factors associated with PK in multivariable analyses are shown (Table). The factor most associated with PK at Dose 1 was sex, with higher Cmax/AUC and lower CL and Vss/longer t½ in women vs. men. PK at Dose 6 was not consistently associated with any factor tested. Median Cmax and Cmin values were similar at first dose between pts who had CR, partial response (PR)/nPR, and stable disease (SD)/progressive disease (PD; Figure); at later doses, median Cmax and Cmin values appeared different between CR and the other groups, although number of subjects decreased over time, especially in the SD/PD group. Based on univariable analyses, higher Cmax and Cmin at Dose 3 and higher Cmax and AUC at Dose 6 were associated with increased likelihood of CR (P<.05); higher Cmin before Dose 6 was associated with increased likelihood of OR and longer PFS. Conclusions: PK of O in combination with FC appeared proportional to dose after repeated dosing. Higher concentrations at Doses 3 and 6 were associated with CR. O PK was similar at first dose and different at later doses between patients who had CR, PR/nPR, and SD/PD, suggesting that response to O-FC treatment leads to clearance differences due to decreased B-cell mass and thus concentration differences with continued dosing. Further analyses of associations between disease-related factors, PK, and treatment response will be performed at study completion. Disclosures: Wierda: GlaxoSmithKline: Research Funding; Genentech: Consultancy, Speakers Bureau; Celgene: Consultancy, Speakers Bureau; Merck: Consultancy; Abbott: Research Funding. Off Label Use: Ofatumumab is an anti-CD20 monoclonal antibody approved for the treatment of fludarabine- and alemtuzumab-refractory chronic lymphocytic leukemia, and is currently under development for the treatment of B-cell malignancies (chronic lymphocytic leukemia, diffuse large B-cell lymphoma, Waldenstroms macroglobulinemia and follicular lymphoma), as well as autoimmune diseases (rheumatoid arthritis and multiple sclerosis). Jewell:GlaxoSmithKline: Employment. Kipps:Gilead Sciences: Consultancy, Research Funding; GSK: Research Funding; Genentech: Research Funding; Pharmacyclics: Membership on an entity's Board of Directors or advisory committees; Abbot Industries: Research Funding; Celgene: Consultancy, Research Funding; Igenica: Equity Ownership, Membership on an entity's Board of Directors or advisory committees; Amgen: Research Funding. Dürig:Santaris Pharma: Consultancy, Research Funding; GSK: Speakers Bureau; Roche: Speakers Bureau; Celgene: Research Funding. Stilgenbauer:Genmab: Research Funding; GSK: Consultancy, Honoraria, Research Funding. Smolej:Roche: Honoraria, Travel Grants; GlaxoSmithKline: Honoraria, Membership on an entity's Board of Directors or advisory committees, Travel Grants; Genzyme: Honoraria, Travel Grants. Hernandez-Ilizaliturri:Genmab: Research Funding; Celgene: Honoraria; Amgen: Research Funding. Fang:PharStat: Employment; GSK: Consultancy; Gilead Sciences: Consultancy; Pharmasset Inc: Consultancy. Gorczyca:GlaxoSmithKline: Employment. Chan:GlaxoSmithKline: Employment. Gupta:GlaxoSmithKline: Employment. Lisby:Genmab A/S: Employment.


Leukemia ◽  
2021 ◽  
Author(s):  
Geffen Kleinstern ◽  
J. Brice Weinberg ◽  
Sameer A. Parikh ◽  
Esteban Braggio ◽  
Sara J. Achenbach ◽  
...  

AbstractMonoclonal B-cell lymphocytosis (MBL) is a precursor to CLL. Other than age, sex, and CLL family-history, little is known about factors associated with MBL risk. A polygenic-risk-score (PRS) of 41 CLL-susceptibility variants has been found to be associated with CLL risk among individuals of European-ancestry(EA). Here, we evaluate these variants, the PRS, and environmental factors for MBL risk. We also evaluate these variants and the CLL-PRS among African-American (AA) and EA-CLL cases and controls. Our study included 560 EA MBLs, 869 CLLs (696 EA/173 AA), and 2866 controls (2631 EA/235 AA). We used logistic regression, adjusting for age and sex, to estimate odds ratios (OR) and 95% confidence intervals within each race. We found significant associations with MBL risk among 21 of 41 variants and with the CLL-PRS (OR = 1.86, P = 1.9 × 10−29, c-statistic = 0.72). Little evidence of any association between MBL risk and environmental factors was observed. We observed significant associations of the CLL-PRS with EA-CLL risk (OR = 2.53, P = 4.0 × 10−63, c-statistic = 0.77) and AA-CLL risk (OR = 1.76, P = 5.1 × 10−5, c-statistic = 0.62). Inherited genetic factors and not environmental are associated with MBL risk. In particular, the CLL-PRS is a strong predictor for both risk of MBL and EA-CLL, but less so for AA-CLL supporting the need for further work in this population.


Blood ◽  
2020 ◽  
Vol 136 (Supplement 1) ◽  
pp. 30-31
Author(s):  
Hanyin Wang ◽  
Shulan Tian ◽  
Qing Zhao ◽  
Wendy Blumenschein ◽  
Jennifer H. Yearley ◽  
...  

Introduction: Richter's syndrome (RS) represents transformation of chronic lymphocytic leukemia (CLL) into a highly aggressive lymphoma with dismal prognosis. Transcriptomic alterations have been described in CLL but most studies focused on peripheral blood samples with minimal data on RS-involved tissue. Moreover, transcriptomic features of RS have not been well defined in the era of CLL novel therapies. In this study we investigated transcriptomic profiles of CLL/RS-involved nodal tissue using samples from a clinical trial cohort of refractory CLL and RS patients treated with Pembrolizumab (NCT02332980). Methods: Nodal samples from 9 RS and 4 CLL patients in MC1485 trial cohort were reviewed and classified as previously published (Ding et al, Blood 2017). All samples were collected prior to Pembrolizumab treatment. Targeted gene expression profiling of 789 immune-related genes were performed on FFPE nodal samples using Nanostring nCounter® Analysis System (NanoString Technologies, Seattle, WA). Differential expression analysis was performed using NanoStringDiff. Genes with 2 fold-change in expression with a false-discovery rate less than 5% were considered differentially expressed. Results: The details for the therapy history of this cohort were illustrated in Figure 1a. All patients exposed to prior ibrutinib before the tissue biopsy had developed clinical progression while receiving ibrutinib. Unsupervised hierarchical clustering using the 300 most variable genes in expression revealed two clusters: C1 and C2 (Figure 1b). C1 included 4 RS and 3 CLL treated with prior chemotherapy without prior ibrutinib, and 1 RS treated with prior ibrutinib. C2 included 1 CLL and 3 RS received prior ibrutinib, and 1 RS treated with chemotherapy. The segregation of gene expression profiles in samples was largely driven by recent exposure to ibrutinib. In C1 cluster (majority had no prior ibrutinb), RS and CLL samples were clearly separated into two subgroups (Figure 1b). In C2 cluster, CLL 8 treated with ibrutinib showed more similarity in gene expression to RS, than to other CLL samples treated with chemotherapy. In comparison of C2 to C1, we identified 71 differentially expressed genes, of which 34 genes were downregulated and 37 were upregulated in C2. Among the upregulated genes in C2 (majority had prior ibrutinib) are known immune modulating genes including LILRA6, FCGR3A, IL-10, CD163, CD14, IL-2RB (figure 1c). Downregulated genes in C2 are involved in B cell activation including CD40LG, CD22, CD79A, MS4A1 (CD20), and LTB, reflecting the expected biological effect of ibrutinib in reducing B cell activation. Among the 9 RS samples, we compared gene profiles between the two groups of RS with or without prior ibrutinib therapy. 38 downregulated genes and 10 upregulated genes were found in the 4 RS treated with ibrutinib in comparison with 5 RS treated with chemotherapy. The top upregulated genes in the ibrutinib-exposed group included PTHLH, S100A8, IGSF3, TERT, and PRKCB, while the downregulated genes in these samples included MS4A1, LTB and CD38 (figure 1d). In order to delineate the differences of RS vs CLL, we compared gene expression profiles between 5 RS samples and 3 CLL samples that were treated with only chemotherapy. RS samples showed significant upregulation of 129 genes and downregulation of 7 genes. Among the most significantly upregulated genes are multiple genes involved in monocyte and myeloid lineage regulation including TNFSF13, S100A9, FCN1, LGALS2, CD14, FCGR2A, SERPINA1, and LILRB3. Conclusion: Our study indicates that ibrutinib-resistant, RS-involved tissues are characterized by downregulation of genes in B cell activation, but with PRKCB and TERT upregulation. Furthermore, RS-involved nodal tissues display the increased expression of genes involved in myeloid/monocytic regulation in comparison with CLL-involved nodal tissues. These findings implicate that differential therapies for RS and CLL patients need to be adopted based on their prior therapy and gene expression signatures. Studies using large sample size will be needed to verify this hypothesis. Figure Disclosures Zhao: Merck: Current Employment. Blumenschein:Merck: Current Employment. Yearley:Merck: Current Employment. Wang:Novartis: Research Funding; Incyte: Research Funding; Innocare: Research Funding. Parikh:Verastem Oncology: Honoraria; GlaxoSmithKline: Honoraria; Pharmacyclics: Honoraria, Research Funding; MorphoSys: Research Funding; Ascentage Pharma: Research Funding; Genentech: Honoraria; AbbVie: Honoraria, Research Funding; Merck: Research Funding; TG Therapeutics: Research Funding; AstraZeneca: Honoraria, Research Funding; Janssen: Honoraria, Research Funding. Kenderian:Sunesis: Research Funding; MorphoSys: Research Funding; Humanigen: Consultancy, Patents & Royalties, Research Funding; Gilead: Research Funding; BMS: Research Funding; Tolero: Research Funding; Lentigen: Research Funding; Juno: Research Funding; Mettaforge: Patents & Royalties; Torque: Consultancy; Kite: Research Funding; Novartis: Patents & Royalties, Research Funding. Kay:Astra Zeneca: Membership on an entity's Board of Directors or advisory committees; Acerta Pharma: Research Funding; Juno Theraputics: Membership on an entity's Board of Directors or advisory committees; Dava Oncology: Membership on an entity's Board of Directors or advisory committees; Oncotracker: Membership on an entity's Board of Directors or advisory committees; Sunesis: Research Funding; MEI Pharma: Research Funding; Agios Pharma: Membership on an entity's Board of Directors or advisory committees; Bristol Meyer Squib: Membership on an entity's Board of Directors or advisory committees, Research Funding; Tolero Pharmaceuticals: Membership on an entity's Board of Directors or advisory committees, Research Funding; Abbvie: Research Funding; Pharmacyclics: Membership on an entity's Board of Directors or advisory committees, Research Funding; Rigel: Membership on an entity's Board of Directors or advisory committees; Morpho-sys: Membership on an entity's Board of Directors or advisory committees; Cytomx: Membership on an entity's Board of Directors or advisory committees. Braggio:DASA: Consultancy; Bayer: Other: Stock Owner; Acerta Pharma: Research Funding. Ding:DTRM: Research Funding; Astra Zeneca: Research Funding; Abbvie: Research Funding; Merck: Membership on an entity's Board of Directors or advisory committees, Research Funding; Octapharma: Membership on an entity's Board of Directors or advisory committees; MEI Pharma: Membership on an entity's Board of Directors or advisory committees; alexion: Membership on an entity's Board of Directors or advisory committees; Beigene: Membership on an entity's Board of Directors or advisory committees.


Blood ◽  
2019 ◽  
Vol 134 (Supplement_1) ◽  
pp. 5468-5468
Author(s):  
Shuo Ma ◽  
Rebecca J Chan ◽  
Lin Gu ◽  
Guan Xing ◽  
Nishan Rajakumaraswamy ◽  
...  

Introduction: Idelalisib (IDELA) is the first-in-class PI3Kδ inhibitor and is approved as a monotherapy for relapsed or refractory (R/R) follicular lymphoma and in combination with rituximab for R/R chronic lymphocytic leukemia (CLL). We previously evaluated IDELA treatment interruption as a mechanism to mitigate treatment-emergent adverse events (TEAEs) and found that limited interruption with clinically appropriate re-challenging resulted in superior clinical outcomes. These findings did not comprehensively address the potential confound of interruptions inherently being associated with longer duration of therapy (DoT). Furthermore, the compound effect of IDELA dose reduction together with treatment interruption on IDELA efficacy was not assessed. Objectives: 1) To evaluate whether the benefit of IDELA interruption is retained in patients on therapy >180 days, a duration previously found to be associated with longer overall survival among patients who discontinued IDELA due to an AE; and 2) To compare clinical outcomes of patients who reduced IDELA dosing in addition to interrupting IDELA with those of patients who interrupted IDELA without additional dose reduction. Methods: Using data from Gilead-sponsored trials of patients with R/R indolent non-Hodgkin's lymphoma (iNHL) treated with IDELA monotherapy (N=125, Gopal et al., N. Engl. J. Med., 2014) or with R/R CLL treated with IDELA + anti-CD20 (N=110, Furman et al., N. Engl. J. Med., 2014; and N=173, Jones et al., Lancet Haematol., 2017), DoT, progression-free survival (PFS), and overall survival (OS) were compared between patients on IDELA therapy >180 days with vs. without interruption and between patients who experienced Interruption and Dose Reduction (IDR) vs. patients who experienced Interruption but NoDose Reduction (INoDR) at any point during IDELA treatment. Interruption was defined as missing at least one IDELA treatment day due to an AE and dose reduction could have occurred before or after the first interruption. PFS and OS were estimated using the Kaplan-Meier method and were compared using a log-rank test. Results: Sixty-nine of 125 patients with R/R iNHL (55.2%) and 222 of 283 patients with R/R CLL (78.4%) remained on IDELA therapy >180 days with 29 (42.0%) and 103 (46.4%) of them, respectively, experiencing interruption on or after day 180 (Table 1). The proportions of patients with interruption before day 180 were similar within each of these populations. Among patients on therapy >180 days, those with treatment interruption on or after 180 days had a longer median (m) DOT than patients without interruption (Table 1). Both PFS and OS were longer in CLL patients who interrupted compared to those who did not interrupt (mPFS=28.9 mos. vs. 17.3 mos. and mOS=not reached [NR] vs. 40.4 mos. for with interruption vs. without interruption, respectively, Table 1 and Figure 1). In patients with iNHL, no difference was observed in PFS or OS between patients who interrupted vs. those who did not (Table 1). Of patients who experienced at least one AE-induced interruption at any point during IDELA therapy (n=63 iNHL and n=157 CLL), 47 iNHL patients (74.6%) and 84 CLL patients (53.5%) also had dose reduction. Two iNHL patients (1.6%) and 5 CLL patients (1.8%) had IDELA dose reduction but no interruption. Both iNHL and CLL patients with IDR experienced a similar PFS compared to patients with INoDR (mPFS=16.5 mos. vs. 14.2 mos. for iNHL and 21.8 mos. vs. 22.1 mos. for CLL with IDR vs. INoDR, respectively, Table 2). However, OS was longer in both iNHL and CLL patients with IDR compared to INoDR (mOS=61.2 mos. vs. 35.3 mos. for iNHL and NR vs. 42.4 mos. for CLL, respectively, Table 2; CLL patients shown in Figure 2). Discussion: IDELA treatment interruption is not associated with rapid clinical deterioration, as observed with some B-cell receptor signaling pathway inhibitors. No clear relationship between IDELA DoT and frequency of interruption was observed. When normalized for DoT >180 days, IDELA treatment interruption retained its clinical benefit in the CLL population. When utilized together with IDELA interruption, dose reduction did not lead to inferior clinical outcomes but instead extended OS in both iNHL and CLL populations. Adherence to treatment interruption and dose reduction guidance as outlined in the IDELA USPI may optimize IDELA tolerability and efficacy for patients with iNHL and CLL. Disclosures Ma: Janssen: Consultancy, Speakers Bureau; Pharmacyclics: Consultancy, Research Funding, Speakers Bureau; Gilead: Research Funding; Abbvie: Research Funding; Juno: Research Funding; Incyte: Research Funding; Xeme: Research Funding; Beigene: Research Funding; Novartis: Research Funding; Astra Zeneca: Consultancy, Research Funding, Speakers Bureau; Kite: Consultancy; Acerta: Research Funding; Bioverativ: Consultancy; Genentech: Consultancy. Chan:Gilead Sciences, Inc.: Employment, Equity Ownership. Gu:Gilead Sciences, Inc.: Employment. Xing:Gilead Sciences, Inc.: Employment. Rajakumaraswamy:Gilead Sciences, Inc.: Employment. Ruzicka:Gilead Sciences, Inc.: Employment. Wagner-Johnston:Gilead: Membership on an entity's Board of Directors or advisory committees; ADC Therapeutics: Membership on an entity's Board of Directors or advisory committees; Jannsen: Membership on an entity's Board of Directors or advisory committees; Bayer: Membership on an entity's Board of Directors or advisory committees.


Blood ◽  
2018 ◽  
Vol 131 (23) ◽  
pp. 2541-2551 ◽  
Author(s):  
Geffen Kleinstern ◽  
Nicola J. Camp ◽  
Lynn R. Goldin ◽  
Celine M. Vachon ◽  
Claire M. Vajdic ◽  
...  

Key Points PRS, based on the known CLL loci, predicts CLL risk with high discrimination. This PRS predicts risk of monoclonal B-cell lymphocytosis, a precursor to CLL and a condition that has clinical impact beyond risk for CLL.


Blood ◽  
2011 ◽  
Vol 118 (21) ◽  
pp. 3867-3867
Author(s):  
Raymond P. Wu ◽  
Christina C.N. Wu ◽  
Tomoko Hayashi ◽  
Laura Z. Rassenti ◽  
Thomas J. Kipps ◽  
...  

Abstract Abstract 3867 Introduction: Despite their mature appearance, the B cells from chronic lymphocytic leukemia (CLL) possess immature characteristics both functionally and biochemically. CLL B cells display known biochemical markers characteristic of cells early in the blood lineage, including ROR1, Wnt16, and LEF1. In addition, CLL B cells have higher levels of Reactive Oxygen Species (ROS) and of the oxidant-induced transcription factor Nrf2 [NFE2L2], compared to normal peripheral blood mononuclear cells (PBMC). Intracellular ROS status has been suggested to be a marker of cancer stem/progenitor cells possibly due to their high expression of oncogenes. Downstream targets of Nrf2 include the Aldehyde dehydrogenase [ALDH] enzymes, which are believed to play a crucial role in stem cell biology because they protect the cells against oxidative stress caused by accumulation of aldehydes. Here, we use ALDH activity to visualize populations of CLL B cells that may have stem/progenitor properties. Materials and Methods: Isolated PBMC from normal donors and CLL patients with aggressive and indolent disease were stained for ALDH activity with an Aldefluor assay kit (StemCell Technologies). The ALDH inhibitor, diethylaminobenzaldehyde (DEAB), was used to confirm that the fluorescent activity was due to ALDH activity. At the end of the Aldefluor assay, the cells were stained for cell surface markers, CD19, CD5, CD38 and CD34. 50,000 total events were collected for FACS analysis. Normalized Mean Fluorescence Intensity (MFI) values were calculated by dividing each MFI value to average MFI value of normal CD19+ cells for each experiment. Data analyses were performed by FlowJo software and Prizm. P-values were calculated by One-Way ANOVA analysis with Post-Bonferroni's multiple comparison test. Results: We examine the level of ALDH expression and activity in CD19+ cells of healthy donors (n = 9), CLL samples that expressed unmutated IgVH and that were ZAP-70 positive (defined as “aggressive”, n = 14) or samples that expressed mutated IgVH and were ZAP-70 negative (defined as “indolent”, n=12). CLL B cells from patients with aggressive disease had significantly higher ALDH activities compared to normal B cells (p < 0.001) and indolent CLL B cells (p < 0.05) (Figure1). Indolent CLL B cells also have higher level of ALDH activities compared to normal B cells (p < 0.01) (Figure1). Treatment with the ALDH inhibitor, DEAB, suppressed the increased fluorescence observed in CLL B cells. In addition, ALDH high CLL B cells are CD34 negative. These data show that CLL B cells express a marker known to be associated with stem/progenitor cells, but these populations are different from CD34 positive hematopoietic stem cells. In addition, our data show that a stem/progenitor cell marker is associated with the pathogenesis of CLL. Disclosures: Kipps: Igenica: Equity Ownership, Membership on an entity's Board of Directors or advisory committees; Celgene: Consultancy, Research Funding; Abbot Industries: Research Funding; Pharmacyclics: Membership on an entity's Board of Directors or advisory committees; Genentech: Research Funding; GSK: Research Funding; Gilead Sciences: Consultancy, Research Funding; Amgen: Research Funding.


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