| 1. |
- Conrotto, Paolo, et al.
(author)
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Knock-down of SOX11 induces autotaxin-dependent increase in proliferation in vitro and more aggressive tumors in vivo
- 2011
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In: Molecular Oncology. - : Wiley. - 1574-7891. ; 5, s. 527-537
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Journal article (peer-reviewed)abstract
- Abstract in UndeterminedThe transcription factor SOX11 is a novel diagnostic marker for mantle cell lymphoma (MCL), distinguishing this aggressive tumor from potential simulators. Recent data also show that the level of SOX11 correlates to in vitro growth properties in MCL, as well as the clinical progression. We have previously shown that MCL-associated pathways, such as Rb-E2F, are dysregulated leading to decreased proliferation upon overexpression of SOX11, emphasizing the impact of SOX11 on MCL-specific gene expression and growth control. However, it remains to be determined which growth regulatory pathways that are induced upon SOX11 knock-down, leading to an increased cellular growth. Consequently, we established a model cell line with constitutive down-regulation of SOX11. The highly proliferative features of this cell line were investigated by gene expression analysis, proliferation assay, cell cycle distribution and potential to induce tumors in NOD-SCID mice. Our in vitro studies demonstrated a SOX11-dependent regulation of MCL-specific gene expression. In addition, we identified autotaxin (ATX) to be regulated by SOX11. Our results clearly showed a correlation between SOX11 level and cellular growth rate, which was dependent on ATX, as well as a direct relation between the level of SOX11 in tumorigenic cells and the growth rate of these tumors in NOD-SCID mice.
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| 2. |
- Emruli, Venera Kuci, et al.
(author)
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Identification of V-ATPase as a molecular sensor of SOX11-levels and potential therapeutic target for mantle cell lymphoma
- 2016
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In: BMC Cancer. - : Springer Science and Business Media LLC. - 1471-2407. ; 16:1
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Journal article (peer-reviewed)abstract
- Background: Mantle cell lymphoma (MCL) is an aggressive disease with short median survival. Molecularly, MCL is defined by the t(11;14) translocation leading to overexpression of the CCND1 gene. However, recent data show that the neural transcription factor SOX11 is a disease defining antigen and several involved signaling pathways have been pin-pointed, among others the Wnt/β-catenin pathway that is of importance for proliferation in MCL. Therefore, we evaluated a compound library focused on the Wnt pathway with the aim of identifying Wnt-related targets that regulate growth and survival in MCL, with particular focus on SOX11-dependent growth regulation. Methods: An inducible SOX11 knock-down system was used to functionally screen a library of compounds (n = 75) targeting the Wnt signaling pathway. A functionally interesting target, vacuolar-type H+-ATPase (V-ATPase), was further evaluated by western blot, siRNA-mediated gene silencing, immunofluorescence, and flow cytometry. Results: We show that 15 out of 75 compounds targeting the Wnt pathway reduce proliferation in all three MCL cell lines tested. Furthermore, three substances targeting two different targets (V-ATPase and Dkk1) showed SOX11-dependent activity. Further validation analyses were focused on V-ATPase and showed that two independent V-ATPase inhibitors (bafilomycin A1 and concanamycin A) are sensitive to SOX11 levels, causing reduced anti-proliferative response in SOX11 low cells. We further show, using fluorescence imaging and flow cytometry, that V-ATPase is mainly localized to the plasma membrane in primary and MCL cell lines. Conclusions: We show that SOX11 status affect V-ATPase dependent pathways, and thus may be involved in regulating pH in intracellular and extracellular compartments. The plasma membrane localization of V-ATPase indicates that pH regulation of the immediate extracellular compartment may be of importance for receptor functionality and potentially invasiveness in vivo.
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| 3. |
- Freiburghaus, Catja, et al.
(author)
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Bortezomib prevents cytarabine resistance in MCL, which is characterized by down-regulation of dCK and up-regulation of SPIB resulting in high NF-κB activity
- 2018
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In: BMC Cancer. - : Springer Science and Business Media LLC. - 1471-2407. ; 18:1
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Journal article (peer-reviewed)abstract
- BACKGROUND: The addition of high-dose cytarabine to the treatment of mantle cell lymphoma (MCL) has significantly prolonged survival of patients, but relapses are common and are normally associated with increased resistance. To elucidate the mechanisms responsible for cytarabine resistance, and to create a tool for drug discovery investigations, we established a unique and molecularly reproducible cytarabine resistant model from the Z138 MCL cell line.METHODS: Effects of different substances on cytarabine-sensitive and resistant cells were evaluated by assessment of cell proliferation using [methyl-14C]-thymidine incorporation and molecular changes were investigated by protein and gene expression analyses.RESULTS: Gene expression profiling revealed that major transcriptional changes occur during the initial phase of adaptation to cellular growth in cytarabine containing media, and only few key genes, including SPIB, are deregulated upon the later development of resistance. Resistance was shown to be mediated by down-regulation of the deoxycytidine kinase (dCK) protein, responsible for activation of nucleoside analogue prodrugs. This key event, emphasized by cross-resistance to other nucleoside analogues, did not only effect resistance but also levels of SPIB and NF-κB, as assessed through forced overexpression in resistant cells. Thus, for the first time we show that regulation of drug resistance through prevention of conversion of pro-drug into active drug are closely linked to increased proliferation and resistance to apoptosis in MCL. Using drug libraries, we identify several substances with growth reducing effect on cytarabine resistant cells. We further hypothesized that co-treatment with bortezomib could prevent resistance development. This was confirmed and show that the dCK levels are retained upon co-treatment, indicating a clinical use for bortezomib treatment in combination with cytarabine to avoid development of resistance. The possibility to predict cytarabine resistance in diagnostic samples was assessed, but analysis show that a majority of patients have moderate to high expression of dCK at diagnosis, corresponding well to the initial clinical response to cytarabine treatment.CONCLUSION: We show that cytarabine resistance potentially can be avoided or at least delayed through co-treatment with bortezomib, and that down-regulation of dCK and up-regulation of SPIB and NF-κB are the main molecular events driving cytarabine resistance development.
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| 4. |
- Kuci Emruli, Venera, et al.
(author)
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Identification of a serum biomarker signature associated with metastatic prostate cancer
- 2021
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In: Proteomics - Clinical Applications. - : Wiley. - 1862-8346 .- 1862-8354. ; 15:2-3
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Journal article (peer-reviewed)abstract
- Purpose: Improved early diagnosis and determination of aggressiveness of prostate cancer (PC) is important to select suitable treatment options and to decrease over-treatment. The conventional marker is total prostate specific antigen (PSA) levels in blood, but lacks specificity and ability to accurately discriminate indolent from aggressive disease. Experimental design: In this study, we sought to identify a serum biomarker signature associated with metastatic PC. We measured 157 analytes in 363 serum samples from healthy subjects, patients with non-metastatic PC and patients with metastatic PC, using a recombinant antibody microarray. Results: A signature consisting of 69 proteins differentiating metastatic PC patients from healthy controls was identified. Conclusions and clinical relevance: The clinical value of this biomarker signature requires validation in larger independent patient cohorts before providing a new prospect for detection of metastatic PC.
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| 5. |
- Kuci, Venera
(author)
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A Molecular Dissection of Mantle Cell Lymphoma - From gene expression analysis to functional evaluation of selected targets
- 2016
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Doctoral thesis (other academic/artistic)abstract
- Mantle cell lymphoma (MCL) is an aggressive form of B-cell lymphoma (BCL) with poor clinical outcome. In this thesis, which is based upon five original papers, different approaches have been used to pinpoint and investigate molecular events that promote MCL tumor growth, progression or resistance to treatment. The aim has been to identify novel targets with the potential to eradicate malignant cells, including more resistant cell clones. In Paper I-III, a previously defined MCL specific disease marker, SOX11, was functionally studied. Our results demonstrate that SOX11 is a tumor suppressor-like gene, exhibiting a central role in MCL tumor growth control. Using gene expression studies, we identified HIG-2 and CD24 as important downstream targets of SOX11, and due to their cell surface localization on MCL cells they are considered of potential therapeutic interest. Moreover, using functional screening with substances targeting components of the WNT pathway, WNT-related targets with SOX11-dependent growth regulation were identified. One of the targets, V-ATPase, a pH regulator, was shown to be sensitive to SOX11 levels. Validation studies confirmed that V-ATPase is localized on the plasma membrane of MCL cells, and is thus an interesting candidate for antibody-based treatment. Despite the high response rate of MCL patients to initial treatment, a large number of patients relapse with a more treatment resistant disease. In Paper IV, the molecular mechanism behind developed resistance to cytarabine, a commonly used chemotherapeutic in treatment of MCL was investigated. Our results show that resistance to cytarabine in MCL is mediated by down-regulation of dCK at protein level. Importantly, cytarabine resistant cells were also shown to exhibit cross-resistance to other chemotherapeutic drugs (nucleoside analogues) acting similarly to cytarabine. Considering these findings, patients demonstrating cytarabine resistance in clinic should be offered non-nucleoside analogue based treatment. Finally, in Paper V, we investigated the presence of a rare population of more treatment resistant cells, identified as side population (SP), in MCL. SP cells isolated from MCL patient material exhibited up-regulated expression levels of the early cell activation markers CD69 and CD44, in agreement with a stem-cell like origin. Of major importance, an enrichment of SP cells was observed in chemotherapy exposed cells, indicating that SP cells have functionally important features, and need to be further investigated in MCL.
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| 6. |
- Kuci, Venera, et al.
(author)
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Emerging role of SOX11 in mantle cell lymphoma
- 2015
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In: Blood and Lymphatic Cancer: Targets and Therapy. - 1179-9889. ; 5, s. 35-41
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Research review (peer-reviewed)abstract
- During recent years the neural transcription factor SOX11 has been established as an important biomarker for mantle cell lymphoma. SOX11 is both a diagnostic and prognostic antigen, and may potentially be used for treatment selection for younger patients, in relation to protocols including high dose chemotherapy. The molecular pathways involved are still not fully elucidated and, as SOX11 can interact with several co-transcription factors, functional assays need to be carefully designed to pinpoint SOX11-specific function in a defined cellular context. Furthermore, as SOX11 belongs to a large family of homologous proteins, analysis of SOX11 has been limited by the availability of specific antibodies for detection and pull-down. In this review, we discuss the emerging role of SOX11 in mantle cell lymphoma and discuss the potential impact in relation to tumorigenesis, diagnostics, prognostics, and therapy.
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| 7. |
- Kuci, Venera, et al.
(author)
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SOX11 and HIG-2 are cross-regulated and affect growth in mantle cell lymphoma.
- 2016
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In: Leukemia & Lymphoma. - : Informa UK Limited. - 1029-2403 .- 1042-8194.
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Journal article (peer-reviewed)abstract
- The transcriptional factor SOX11 is a disease-defining antigen in mantle cell lymphoma (MCL) and absent in most non-malignant tissues. To explore the role of SOX11-related cell signaling, and potentially take benefit from these for targeted therapy, associated networks and proteins need to be defined. In this study, we used an inducible SOX11 knock-down system followed by gene expression analysis to identify co-regulated genes and associated signaling pathways. A limited number (n = 27) of significantly co-regulated genes were identified, including SETMAR, HIG-2, and CD24. Further analysis confirmed co-regulation of SOX11 with HIG-2 and CD24 at the protein level. Of major interest, knock-down of HIG-2 reduced SOX11 levels and increased proliferation, the proteins are thus cross-regulated. HIG-2 was localized at the plasma cell membrane in both cell lines and primary MCL cells, and could potentially be of interest for targeted therapy.
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| 8. |
- Lokhande, Lavanya, et al.
(author)
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Immune-related protein signature in serum stratify relapsed mantle cell lymphoma patients based on risk
- 2020
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In: BMC Cancer. - : Springer Science and Business Media LLC. - 1471-2407. ; 20:1
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Journal article (peer-reviewed)abstract
- Background: Response to modern treatment strategies, which combine cytotoxic compounds with immune stimulatory agents and targeted treatment is highly variable among MCL patients. Thus, providing prognostic and predictive markers for risk adapted therapy is warranted and molecular information that can help in patient stratification is a necessity. In relapsed MCL, biopsies are rarely available and molecular information from tumor tissue is often lacking. Today, the main tool to access risk is the MCL international prognostic index (MIPI), which does not include detailed biological information of relevance for different treatment options. To enable continuous monitoring of patients, non-invasive companion diagnostic tools are needed which can further reduce cost and patient distress and enable efficient measurements of biological markers. Methods: We have assessed if serum-based protein profiling can identify immune related proteins that stratify relapsed MCL patients based on risk. Overall, 371 scFv targeting 158 proteins were assessed using an antibody microarray platform. We profiled patients (n = 44) who had been treated within the MCL6-Philemon trial combining targeted and immune-modulatory treatment. Results: The downstream processing led to the identification of the relapsed immune signature (RIS) consisting of 11 proteins with potential to stratify patients with long and short overall survival (OS). Moreover, in this population, MIPI alone failed to separate high, intermediate and low risk patients, but a combined index based on MIPI together with RIS, MIPIris, showed improved performance and significantly stratified all three risk groups based on OS. Conclusions: Our results show that addition of biological parameters to previous prognostic indices improves patient stratification among patients treated with BTK inhibitor triplet combination, particularly, in the identification of an extreme high risk group.
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| 9. |
- Lokhande, Lavanya, et al.
(author)
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Serum proteome modulations upon treatment provides biological insight on response to treatment in relapsed mantle cell lymphoma
- 2022
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In: Cancer Reports. - : Wiley. - 2573-8348. ; 5:7
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Journal article (peer-reviewed)abstract
- Background: The possibility to monitor patient's serum proteome during treatment can provide deepened understanding of the biology associated with response to specific drugs. Non-invasive serum sampling provides an opportunity for sustainable repetitive sampling of patients, which allows for more frequent evaluation of the biological response and enhanced flexibility in treatment selection in contrast to tissue biopsies. Aim: To pin-point biologically relevant changes in pre- and on-treatment serum proteome samples in relapsed mantle cell lymphoma (MCL) patients, leading to insight into mechanisms behind response to treatment in sub-groups of patients. Methods: Pre- and on-treatment serum samples from relapsed MCL patients treated with a triple combination therapy of rituximab, ibrutinib and lenalidomide were available for the study, together with detailed clinicopathological information. A microarray technology targeting 158 serum proteins using 371 antibody-fragments was used to compare the serum proteome at the two time-points. Results: Proteins modulated by the treatment were shown to be associated to a MCL sub-group with ATM/TP53 alterations, which emphasizes the importance of treatment stratification. Absolute values of serum protein levels in on-treatment samples were highly variable and showed no correlation to outcome. To circumvent the challenge of variability in absolute serum protein levels, the velocity of change of individual serum proteins was used to identify proteins associated with clinical response. Increased values of TGF-β1, CD40 and complement component 4 comparing pre- and on-treatment samples were associated with remaining minimal residual disease (MRD) and increased BTK was associated with short progression-free survival (PFS). Conclusion: We show that the genetic sub-type of MCL affects the biological response to treatment in serum and that the change in defined serum proteins reveals the biology associated with clinical response.
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| 10. |
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| 11. |
- Nordström, Lena, et al.
(author)
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DNA methylation and histone modifications regulate SOX11 expression in lymphoid and solid cancer cells.
- 2015
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In: BMC Cancer. - : Springer Science and Business Media LLC. - 1471-2407. ; 15:1
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Journal article (peer-reviewed)abstract
- The neural transcription factor SOX11 is present at specific stages during embryo development with a very restricted expression in adult tissue, indicating precise regulation of transcription. SOX11 is strongly up-regulated in some malignancies and have a functional role in tumorgenesis. With the aim to explore differences in epigenetic regulation of SOX11 expression in normal versus neoplastic cells, we investigated methylation and histone modifications related to the SOX11 promoter and the possibility to induce re-expression using histone deacetylase (HDAC) or EZH2 inhibitors.
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| 12. |
- Papakonstantinou, Nikos, et al.
(author)
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Integrated epigenomic and transcriptomic analysis reveals TP63 as a novel player in clinically aggressive chronic lymphocytic leukemia
- 2019
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In: International Journal of Cancer. - : Wiley. - 0020-7136 .- 1097-0215. ; 144:11, s. 2695-2706
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Journal article (peer-reviewed)abstract
- Chronic lymphocytic leukemia (CLL) stereotyped subsets #6 and #8 include cases expressing unmutated B cell receptor immunoglobulin (BcR IG) (U-CLL). Subset #6 (IGHV1-69/IGKV3-20) is less aggressive compared to subset #8 (IGHV4-39/IGKV1(D)-39) which has the highest risk for Richter's transformation among all CLL. The underlying reasons for this divergent clinical behavior are not fully elucidated. To gain insight into this issue, here we focused on epigenomic signatures and their links with gene expression, particularly investigating genome-wide DNA methylation profiles in subsets #6 and #8 as well as other U-CLL cases not expressing stereotyped BcR IG. We found that subset #8 showed a distinctive DNA methylation profile compared to all other U-CLL cases, including subset #6. Integrated analysis of DNA methylation and gene expression revealed significant correlation for several genes, particularly highlighting a relevant role for the TP63 gene which was hypomethylated and overexpressed in subset #8. This observation was validated by quantitative PCR, which also revealed TP63 mRNA overexpression in additional nonsubset U-CLL cases. BcR stimulation had distinct effects on p63 protein expression, particularly leading to induction in subset #8, accompanied by increased CLL cell survival. This pro-survival effect was also supported by siRNA-mediated downregulation of p63 expression resulting in increased apoptosis. In conclusion, we report that DNA methylation profiles may vary even among CLL patients with similar somatic hypermutation status, supporting a compartmentalized approach to dissecting CLL biology. Furthermore, we highlight p63 as a novel prosurvival factor in CLL, thus identifying another piece of the complex puzzle of clinical aggressiveness. What's new? In chronic lymphocytic leukemia (CLL), cases with unmutated immunoglobulin receptors (U-CLL) are generally associated with inferior outcome, albeit still displaying considerable heterogeneity. Might such differences in CLL progression be explained by epigenetics? In this study, the authors found that an unusually aggressive subset of CLLs called subset #8 has a distinctive DNA-methylation profile. They also found that p63 is a novel pro-survival factor for CLL cells. These molecular studies may lead to new prognostic biomarkers, and possibly new therapeutic targets, for CLL.
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| 13. |
- Rosenquist, Richard, et al.
(author)
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Genome-Wide DNA Methylation Profiling of Chronic Lymphocytic Leukemia Subsets Carrying Stereotyped B Cell Receptors
- 2017
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In: Blood. - 0006-4971. ; 130:Suppl 1, s. 57-57
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Conference paper (other academic/artistic)abstract
- In recent years, subsets of chronic lymphocytic leukemia (CLL) patients carrying quasi-identical or stereotyped B cell receptors (BcRs) have been identified that share clinicobiological features and disease outcome. While these stereotyped subsets show distinct gene expression and genomic profiles, the DNA methylation landscape remains largely unexplored. By applying high-resolution 450K methylation arrays, we investigated 176 CLL subset cases belonging to: (i) the clinically aggressive, IGHV-unmutated (U-CLL) subsets $$1 (clan I genes/IGKV(D)1-39, n=37) and $$8 (IGHV4-39/IGKV1(D)-39, n=21); (ii) the IGHV1-69-expressing U-CLL subsets $$3 (n=12), $$5 (n=9), $$6 (n=22), and $$7 (n=12); and, (iii) the indolent, IGHV-mutated (M-CLL) subset $$4 (IGHV4-34/IGKV2-30, n=28). In addition, we included subset $$2 cases (IGHV3-21/IGLV3-21, mixed mutation status, n=35) that have a poor outcome independent of IGHV mutation status. For comparative purposes, we included a cohort of CLL cases that do not express stereotyped BcRs ('non-subset', n=325). These patients were subgrouped according to the recently proposed epigenetic classification of CLL, i.e. poor-prognostic, naive-like CLL (n-CLL, n=102), favorable-prognostic, memory-like CLL (m-CLL; n=176), broadly corresponding to U-CLL and M-CLL, respectively, and a third intermediate CLL subgroup (i-CLL; n=47), which express borderline mutated IGHV genes and have an intermediate prognosis. Finally, a series of sorted normal subpopulations spanning different stages of B-cell differentiation [precursors (n=22), naive B cells (n=19) and germinal center/memory B-cells (n=33)] were also included in the analysis. Overall, unsupervised analysis of subset vs. non-subset CLL revealed that all U-CLL subsets clustered with n-CLL, subset $$4 clustered with m-CLL, while subset $$2 clustered separately with i-CLL (Figure 1). Supervised analysis revealed a limited number of CpG sites that were differentially methylated when comparing each U-CLL or M-CLL subset with non-subset cases. In contrast, almost all subset $$2 cases clustered separately from i-CLL in supervised analysis, indicating that this subset might represent a distinct subgroup of i-CLL. We recently demonstrated that the number of epigenetic changes that a tumor acquires, compared to its cellular origin (i.e. 'epigenetic burden'), may be a powerful predictor of clinical aggressiveness (Queiros et al, Cancer Cell 2016). When adopting this approach in CLL, comparison of specific subsets vs. their non-subset cases matched by epigenetic subgroup, revealed significant differences in the epigenetic burden amongst the various groupings; for instance, in subset $$1 vs. n-CLL (72K vs. 67K, plt;0.05) and in subset $$2 vs. i-CLL (76K vs. 68K, p=0.001), while no difference was observed between subset $$4 vs. m-CLL (83K vs. 82K, p=not significant). Subset $$2 cases frequently carry del(11q) and harbor SF3B1 mutations, however, neither the IGHV mutation status nor the presence of del(11q) or SF3B1 mutations had any impact on the epigenetic burden within subset $$2. In conclusion, U-CLL and M-CLL subsets generally clustered with n-CLL and m-CLL categories, respectively, implying common cellular origins. In contrast, subset $$2 emerged as the first defined member of the i-CLL group, which in turn alludes to a distinct cellular origin and/or pathogenetic process for subset $$2 and i-CLL patients.Disclosures Papakonstantinou: Janssen Pharmaceuticals: Research Funding; Gilead: Research Funding. Smedby: Janssen: Research Funding; Celgene: Membership on an entity's Board of Directors or advisory committees. Gaidano: Roche: Consultancy, Honoraria; Amgen: Consultancy, Honoraria; AbbVie: Consultancy, Honoraria; Gilead: Consultancy, Honoraria; Janssen: Consultancy, Honoraria. Ghia: AbbVie: Consultancy; Adaptive: Consultancy; Gilead: Consultancy, Research Funding, Speakers Bureau; Janssen: Consultancy, Research Funding; Pharmacyclics LLC, an AbbVie Company: Consultancy; Roche: Consultancy; Novartis: Research Funding. Stamatopoulos: Novartis SA: Research Funding; Gilead: Consultancy, Honoraria, Research Funding; Janssen Pharmaceuticals: Honoraria, Research Funding; Abbvie: Honoraria, Research Funding.↵* Asterisk with author names denotes non-ASH members.
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