| 1. |
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| 2. |
- Agathangelidis, Andreas, et al.
(författare)
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Highly similar genomic landscapes in monoclonal B-cell lymphocytosis and ultra-stable chronic lymphocytic leukemia with low frequency of driver mutations
- 2018
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Ingår i: Haematologica. - : Ferrata Storti Foundation (Haematologica). - 0390-6078 .- 1592-8721. ; 103:5, s. 865-873
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Tidskriftsartikel (refereegranskat)abstract
- Despite the recent discovery of recurrent driver mutations in chronic lymphocytic leukemia, the genetic factors involved in disease onset remain largely unknown. To address this issue, we per-formed whole-genome sequencing in 11 individuals with monoclonal B-cell lymphocytosis, both of the low-count and high-count subtypes, and 5 patients with ultra-stable chronic lymphocytic leukemia (>10 years without progression from initial diagnosis). All three entities were indistinguishable at the genomic level exhibiting low genomic complexity and similar types of somatic mutations. Exonic mutations were not frequently identified in putative chronic lymphocytic leukemia driver genes in all settings, including low-count monoclonal B-cell lymphocytosis. To corroborate these findings, we also performed deep sequencing in 11 known frequently mutated genes in an extended cohort of 28 monoclonal B-cell lym phocytosis/chronic lymphocytic leukemia cases. Interestingly, shared mutations were detected between clonal B cells and paired polymorphonuclear cells, strengthening the notion that at least a fraction of somatic mutations may occur before disease onset, likely at the hematopoietic stem cell level. Finally, we identified previously unreported non-coding variants targeting pathways relevant to B-cell and chronic lymphocytic leukemia development, likely associated with the acquisition of the characteristic neoplastic phenotype typical of both monoclonal B-cell lymphocytosis and chronic lymphocytic leukemia.
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| 3. |
- Agathangelidis, Andreas, et al.
(författare)
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Immunoglobulin Gene Sequence Analysis In Chronic Lymphocytic Leukemia : From Patient Material To Sequence Interpretation
- 2018
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Ingår i: Journal of Visualized Experiments. - : JOURNAL OF VISUALIZED EXPERIMENTS. - 1940-087X. ; :141
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Tidskriftsartikel (refereegranskat)abstract
- During B cell maturation, the complex process of immunoglobulin (IG) gene V(D)J recombination coupled with somatic hypermutation (SHM) gives rise to a unique DNA sequence within each individual B cell. Since B cell malignancies result from the clonal expansion of a single cell, IG genes represent a unique molecular signature common to all the malignant cells within an individual patient; thus, IG gene rearrangements can be used as clonal markers. In addition to serving as an important clonal identifier, the IG gene sequence can act as a 'molecular timeline' since it is associated with specific developmental stages and hence reflects the history of the B cell involved in the neoplastic transformation. Moreover, for certain malignancies, in particular chronic lymphocytic leukemia (CLL), the IG gene sequence holds prognostic and potentially predictive capabilities. That said, extrapolating meaningful conclusions from IG gene sequence analysis would be impossible if robust methods and tools were not available to aid in their analysis. This article, drawing on the vast experience of the European Research Initiative on CLL (ERIC), details the technical aspects and essential requirements necessary to ensure reliable and reproducible IG gene sequence analysis in CLL, a test that is now recommended for all CLL patients prior to treatment. More specifically, the various analytical stages are described ranging from the identification of the clonotypic IG gene rearrangement and the determination of the nucleotide sequence to the accurate clinical interpretation of the IG gene sequence data.
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| 4. |
- Agathangelidis, Andreas, et al.
(författare)
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Stereotyped B-cell receptors in chronic lymphocytic leukemia
- 2014
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Ingår i: Leukemia and Lymphoma. - : Informa UK Limited. - 1042-8194 .- 1029-2403. ; 55:10, s. 2252-2261
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Forskningsöversikt (refereegranskat)abstract
- Over the last decade, immunogenetic analysis of B-cell receptor immunoglobulins (BcR IGs) has proved to be a particularly fruitful field in chronic lymphocytic leukemia (CLL), not only for understanding disease pathogenesis but also for discriminating clinical subgroups with markedly distinct course and outcome. Of utmost importance was the identification of quasi-identical BcR IGs among unrelated patients with CLL, fittingly coined as "stereotypy," that set the wheels in motion for unraveling the role of antigen(s) in the selection and expansion of the leukemic clones. The categorization of CLL clones into "subsets" according to shared BcR IG structural characteristics provided a compartmentalized view of this otherwise heterogeneous disease, which eventually led to defining strikingly homogeneous groups of patients in terms of: (i) functional properties of the clonal BcR IGs, e. g. BcR reactivity and signaling; (ii) clonal genetic landscape, e. g. genomic aberrations, gene expression/methylation profiles, microRNA signatures; and (iii) clinical course and outcome. The remarkable restriction of the CLL IG gene repertoire, resulting to a great degree from the high impact of BcR IG stereotypy, may also prompt speculations regarding CLL ontogenesis. Overall, the BcR IG molecule justifiably lies at the heart of CLL clinical research, holding the promise of subset-tailored therapies.
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| 5. |
- Agathangelidis, Andreas, et al.
(författare)
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Stereotyped B-cell receptors in one-third of chronic lymphocytic leukemia : a molecular classification with implications for targeted therapies
- 2012
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Ingår i: Blood. - : American Society of Hematology. - 0006-4971 .- 1528-0020. ; 119:19, s. 4467-4475
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Tidskriftsartikel (refereegranskat)abstract
- Mounting evidence indicates that grouping of chronic lymphocytic leukemia (CLL) into distinct subsets with stereotyped BCRs is functionally and prognostically relevant. However, several issues need revisiting, including the criteria for identification of BCR stereotypy and its actual frequency as well as the identification of "CLL-biased" features in BCR Ig stereotypes. To this end, we examined 7596 Ig VH (IGHV-IGHD-IGHJ) sequences from 7424 CLL patients, 3 times the size of the largest published series, with an updated version of our purpose-built clustering algorithm. We document that CLL may be subdivided into 2 distinct categories: one with stereotyped and the other with nonstereotyped BCRs, at an approximate ratio of 1: 2, and provide evidence suggesting a different ontogeny for these 2 categories. We also show that subset-defining sequence patterns in CLL differ from those underlying BCR stereotypy in other B-cell malignancies. Notably, 19 major subsets contained from 20 to 213 sequences each, collectively accounting for 943 sequences or one-eighth of the cohort. Hence, this compartmentalized examination of VH sequences may pave the way toward a molecular classification of CLL with implications for targeted therapeutic interventions, applicable to a significant number of patients assigned to the same subset.
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| 6. |
- Agathangelidis, Andreas, et al.
(författare)
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Unlocking the secrets of immunoglobulin receptors in mantle cell lymphoma : Implications for the origin and selection of the malignant cells
- 2011
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Ingår i: Seminars in Cancer Biology. - : Elsevier BV. - 1044-579X .- 1096-3650. ; 21:5, s. 299-307
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Forskningsöversikt (refereegranskat)abstract
- Immunogenetic analysis of mantle cell lymphoma (MCL) has offered important evidence helping to decipher the immune pathways leading to its development and also prompting a reappraisal of the views about its ontogeny. In particular, older and more recent studies have demonstrated that MCL is characterized by a highly distinctive immunoglobulin gene repertoire with remarkable predominance of the IGHV3-21 and IGHV4-34 genes; restricted associations of IGHV,IGHD and IGHJ genes, culminating in the creation of quasi-identical ("stereotyped") heavy complementarity-determining region 3 sequences in roughly 10% of cases; and, very precisely targeted and, probably, functionally driven somatic hypermutation, ranging from minimal (in most cases) to pronounced. Furthermore, comparison to other entities, in particular CLL, revealed that several of these immunogenetic features are "MCL-biased". On these grounds, an antigen-driven origin of MCL could be envisaged, at least for subsets of cases.
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| 7. |
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| 8. |
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| 9. |
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| 10. |
- Baliakas, Panagiotis, et al.
(författare)
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Chromosomal translocations and karyotype complexity in chronic lymphocytic leukemia : A systematic reappraisal of classic cytogenetic data
- 2014
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Ingår i: American Journal of Hematology. - : Wiley. - 0361-8609 .- 1096-8652. ; 89:3, s. 249-255
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Tidskriftsartikel (refereegranskat)abstract
- The significance of chromosomal translocations (CTRAs) and karyotype complexity (KC) in chronic lymphocytic leukemia (CLL) remains uncertain. To gain insight into these issues, we evaluated a series of 1001 CLL cases with reliable classic cytogenetic data obtained within 6 months from diagnosis before any treatment. Overall, 320 cases were found to carry 1 CTRAs. The most frequent chromosome breakpoints were 13q, followed by 14q, 18q, 17q, and 17p; notably, CTRAs involving chromosome 13q showed a wide spectrum of translocation partners. KC (3 aberrations) was detected in 157 cases and significantly (P<0.005) associated with unmutated IGHV genes and aberrations of chromosome 17p. Furthermore, it was identified as an independent prognostic factor for shorter time-to-first-treatment. CTRAs were assigned to two categories (i) CTRAs present in the context of KC, often with involvement of chromosome 17p aberrations, occurring mostly in CLL with unmutated IGHV genes; in such cases, we found that KC rather than the presence of CTRAs per se negatively impacts on survival; (ii) CTRAs in cases without KC, having limited if any impact on survival. On this evidence, we propose that all CTRAs in CLL are not equivalent but rather develop by different processes and are associated with distinct clonal behavior. Am. J. Hematol. 89:249-255, 2014. (c) 2013 Wiley Periodicals, Inc.
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| 11. |
- Baliakas, Panagiotis, et al.
(författare)
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Clinical effect of stereotyped B-cell receptor immunoglobulins in chronic lymphocytic leukaemia: a retrospective multicentre study
- 2014
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Ingår i: The Lancet Haematology. - 2352-3026. ; 1:2, s. 74-84
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Tidskriftsartikel (refereegranskat)abstract
- Background About 30% of cases of chronic lymphocytic leukaemia (CLL) carry quasi-identical B-cell receptor immunoglobulins and can be assigned to distinct stereotyped subsets. Although preliminary evidence suggests that B-cell receptor immunoglobulin stereotypy is relevant from a clinical viewpoint, this aspect has never been explored in a systematic manner or in a cohort of adequate size that would enable clinical conclusions to be drawn. Methods For this retrospective, multicentre study, we analysed 8593 patients with CLL for whom immunogenetic data were available. These patients were followed up in 15 academic institutions throughout Europe (in Czech Republic, Denmark, France, Greece, Italy, Netherlands, Sweden, and the UK) and the USA, and data were collected between June 1, 2012, and June 7, 2013. We retrospectively assessed the clinical implications of CLL B-cell receptor immunoglobulin stereotypy, with a particular focus on 14 major stereotyped subsets comprising cases expressing unmutated (U-CLL) or mutated (M-CLL) immunoglobulin heavy chain variable genes. The primary outcome of our analysis was time to first treatment, defined as the time between diagnosis and date of first treatment. Findings 2878 patients were assigned to a stereotyped subset, of which 1122 patients belonged to one of 14 major subsets. Stereotyped subsets showed significant differences in terms of age, sex, disease burden at diagnosis, CD38 expression, and cytogenetic aberrations of prognostic significance. Patients within a specific subset generally followed the same clinical course, whereas patients in different stereotyped subsets-despite having the same immunoglobulin heavy variable gene and displaying similar immunoglobulin mutational status-showed substantially different times to first treatment. By integrating B-cell receptor immunoglobulin stereotypy (for subsets 1, 2, and 4) into the well established Dohner cytogenetic prognostic model, we showed these, which collectively account for around 7% of all cases of CLL and represent both U-CLL and M-CLL, constituted separate clinical entities, ranging from very indolent (subset 4) to aggressive disease (subsets 1 and 2). Interpretation The molecular classification of chronic lymphocytic leukaemia based on B-cell receptor immunoglobulin stereotypy improves the Dohner hierarchical model and refines prognostication beyond immunoglobulin mutational status, with potential implications for clinical decision making, especially within prospective clinical trials.
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| 12. |
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| 13. |
- Baliakas, Panagiotis, 1977-, et al.
(författare)
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Cytogenetic complexity in chronic lymphocytic leukemia : definitions, associations, and clinical impact
- 2019
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Ingår i: Blood. - : American Society of Hematology. - 0006-4971 .- 1528-0020. ; 133:11, s. 1205-1216
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Tidskriftsartikel (refereegranskat)abstract
- Recent evidence suggests that complex karyotype (CK) defined by the presence of >= 3 chromosomal aberrations (structural and/or numerical) identified by using chromosome-banding analysis (CBA) may be relevant for treatment decision-making in chronic lymphocytic leukemia (CLL). However, many challenges toward the routine clinical application of CBA remain. In a retrospective study of 5290 patients with available CBA data, we explored both clinicobiological associations and the clinical impact of CK in CLL. We found that patients with >= 5 abnormalities, defined as high-CK, exhibit uniformly dismal clinical outcomes, independently of clinical stage, TP53 aberrations (deletion of chromosome 17p and/or TP53 mutations [TP53abs]), and the expression of somatically hypermutated (M-CLL) or unmutated immunoglobulin heavy variable genes. Thus, they contrasted with CK cases with 3 or 4 aberrations (low-CK and intermediate-CK, respectively) who followed aggressive disease courses only in the presence of TP53abs. At the other end of the spectrum, patients with CK and 112,119 displayed an exceptionally indolent profile. Building upon CK, TP53abs, and immunoglobulin heavy variable gene somatic hyper-mutation status, we propose a novel hierarchical model in which patients with high-CK exhibit the worst prognosis, whereas those with mutated CLL lacking CK or TP53abs, as well as CK with 112,119, show the longest overall survival. Thus, CK should not be axiomatically considered unfavorable in CLL, representing a heterogeneous group with variable clinical behavior. High-CK with >= 5 chromosomal aberrations emerges as prognostically adverse, independent of other biomarkers. Prospective clinical validation is warranted before ultimately incorporating high-CK in risk stratification of CLL.
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| 14. |
- Baliakas, Panagiotis, 1977-, et al.
(författare)
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Cytogenetics in Chronic Lymphocytic Leukemia : ERIC Perspectives and Recommendations
- 2022
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Ingår i: HemaSphere. - : Ovid Technologies (Wolters Kluwer Health). - 2572-9241. ; 6:4
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Tidskriftsartikel (refereegranskat)abstract
- Mounting evidence underscores the clinical value of cytogenetic analysis in chronic lymphocytic leukemia (CLL), particularly as it allows the identification of complex karyotype, that has recently emerged as a prognostic and potentially predictive biomarker. That said, explicit recommendations regarding the methodology and clinical interpretation of either chromosome banding analysis (CBA) or chromosome microarray analysis (CMA) are still lacking. We herein present the consensus of the Cytogenetic Steering Scientific Committee of ERIC, the European Research Initiative on CLL, regarding methodological issues as well as clinical interpretation of CBA/CMA and discuss their relevance in CLL. ERIC considers CBA standardized and feasible for CLL on the condition that standards are met, extending from the use of novel mitogens to the accurate interpretation of the findings. On the other hand, CMA, is also standardized, however, robust data on its clinical utility are still scarce. In conclusion, cytogenetic analysis is not yet mature enough to guide treatment choices in CLL. That notwithstanding, ERIC encourages the wide application of CBA, and potentially also CMA, in clinical trials in order to obtain robust evidence regarding the predictive value of specific cytogenetic profiles towards refining risk stratification and improving the management of patients with CLL.
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| 15. |
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| 16. |
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| 17. |
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| 18. |
- Baliakas, Panagiotis, et al.
(författare)
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Not all IGHV3-21 chronic lymphocytic leukemias are equal: prognostic considerations.
- 2015
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Ingår i: Blood. - : American Society of Hematology. - 1528-0020 .- 0006-4971. ; 125:5, s. 856-859
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Tidskriftsartikel (refereegranskat)abstract
- An unresolved issue in chronic lymphocytic leukemia (CLL) is whether IGHV3-21 gene usage, in general, or the expression of stereotyped B-cell receptor immunoglobulin defining subset #2 (IGHV3-21/IGLV3-21), in particular, determines outcome for IGHV3-21-utilizing cases. We reappraised this issue in 8593 CLL patients of whom 437 (5%) used the IGHV3-21 gene with 254/437 (58%) classified as subset #2. Within subset #2, immunoglobulin heavy variable (IGHV)-mutated cases predominated, whereas non-subset #2/IGHV3-21 was enriched for IGHV-unmutated cases (P = .002). Subset #2 exhibited significantly shorter time-to-first-treatment (TTFT) compared with non-subset #2/IGHV3-21 (22 vs 60 months, P = .001). No such difference was observed between non-subset #2/IGHV3-21 vs the remaining CLL with similar IGHV mutational status. In conclusion, IGHV3-21 CLL should not be axiomatically considered a homogeneous entity with adverse prognosis, given that only subset #2 emerges as uniformly aggressive, contrasting non-subset #2/IGVH3-21 patients whose prognosis depends on IGHV mutational status as the remaining CLL.
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| 19. |
- Baliakas, Panagiotis, et al.
(författare)
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Prognostic indices in chronic lymphocytic leukaemia : where do we stand how do we proceed?
- 2016
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Ingår i: Journal of Internal Medicine. - : Wiley. - 0954-6820 .- 1365-2796. ; 279:4, s. 347-357
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Forskningsöversikt (refereegranskat)abstract
- The remarkable clinical heterogeneity in chronic lymphocytic leukaemia (CLL) has highlighted the need for prognostic and predictive algorithms that can be employed in clinical practice to assist patient management and therapy decisions. Over the last 20 years, this research field has been rewarding and many novel prognostic factors have been identified, especially at the molecular genetic level. Whilst detection of recurrent cytogenetic aberrations and determination of the immunoglobulin heavy variable gene somatic hypermutation status have an established role in outcome prediction, next-generation sequencing has recently revealed novel mutated genes with clinical relevance (e.g. NOTCH1, SF3B1 and BIRC3). Efforts have been made to combine variables into prognostic indices; however, none has been universally adopted. Although a unifying model for all groups of patients and in all situations is appealing, this may prove difficult to attain. Alternatively, focused efforts on patient subgroups in the same clinical context and at certain clinically relevant 'decision points', that is at diagnosis and at initiation of first-line or subsequent treatments, may provide a more accurate approach. In this review, we discuss the advantages and disadvantages as well as the clinical applicability of three recently proposed prognostic models, the MD Anderson nomogram, the integrated cytogenetic and mutational model and the CLL-international prognostic index. We also consider future directions taking into account novel aspects of the disease, such as the tumour microenvironment and the dynamics of (sub)clonal evolution. These aspects are particularly relevant in view of the increasing number of new targeted therapies that have recently emerged.
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| 20. |
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| 21. |
- Baliakas, Panagiotis, et al.
(författare)
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Recurrent mutations refine prognosis in chronic lymphocytic leukemia
- 2015
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Ingår i: Leukemia. - : Springer Science and Business Media LLC. - 0887-6924 .- 1476-5551. ; 29, s. 329-336
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Tidskriftsartikel (refereegranskat)abstract
- Through the European Research Initiative on chronic lymphocytic leukemia (CLL) (ERIC), we screened 3490 patients with CLL for mutations within the NOTCH1 (n=3334), SF3B1 (n=2322), TP53 (n=2309), MYD88 (n=1080) and BIRC3 (n=919) genes, mainly at diagnosis (75%) and before treatment (>90%). BIRC3 mutations (2.5%) were associated with unmutated IGHV genes (U-CLL), del(11q) and trisomy 12, whereas MYD88 mutations (2.2%) were exclusively found among M-CLL. NOTCH1, SF3B1 and TP53 exhibited variable frequencies and were mostly enriched within clinically aggressive cases. Interestingly, as the timespan between diagnosis and mutational screening increased, so too did the incidence of SF3B1 mutations; no such increase was observed for NOTCH1 mutations. Regarding the clinical impact, NOTCH1 mutations, SF3B1 mutations and TP53 aberrations (deletion/mutation, TP53ab) correlated with shorter time-to-first-treatment (P<0.0001) in 889 treatment-naive Binet stage A cases. In multivariate analysis (n=774), SF3B1 mutations and TP53ab along with del(11q) and U-CLL, but not NOTCH1 mutations, retained independent significance. Importantly, TP53ab and SF3B1 mutations had an adverse impact even in U-CLL. In conclusion, we support the clinical relevance of novel recurrent mutations in CLL, highlighting the adverse impact of SF3B1 and TP53 mutations, even independent of IGHV mutational status, thus underscoring the need for urgent standardization/harmonization of the detection methods.
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| 22. |
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| 23. |
- Baliakas, Panagiotis, et al.
(författare)
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Splenic marginal-zone lymphoma : ontogeny and genetics
- 2015
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Ingår i: Leukemia and Lymphoma. - : Informa UK Limited. - 1042-8194 .- 1029-2403. ; 56:2, s. 301-310
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Forskningsöversikt (refereegranskat)abstract
- Splenic marginal-zone lymphoma (SMZL) is a rare tumor that has recently emerged as a prototype for how the interplay between genetics and environment shapes the natural history of lymphomas. Indeed, the recent identification of molecular immunogenetic subgroups within SMZL may prove to be relevant not only for the sub-classification of the disease but also for improved understanding of the underlying biology. In contrast to other B-cell lymphomas, SMZL lacks a characteristic genetic lesion, although the majority of cases harbor genomic aberrations, as recently revealed by high-throughput studies that identified recurrent genetic aberrations, several in pathways related to marginal-zone differentiation and B-cell signaling. Here we provide an overview of recent research into the molecular and cellular biology of SMZL and related disorders, with special emphasis on immunogenetics and genomic aberrations, and discuss the value of molecular and cellular markers for the diagnosis and differential diagnosis of these entities.
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| 24. |
- Baliakas, Panagiotis, 1977-, et al.
(författare)
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Tailored approaches grounded on immunogenetic features for refined prognostication in chronic lymphocytic leukemia
- 2019
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Ingår i: Haematologica. - : Ferrata Storti Foundation (Haematologica). - 1592-8721 .- 0390-6078. ; 104:2, s. 360-369
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Tidskriftsartikel (refereegranskat)abstract
- Chronic lymphocytic leukemia (CLL) patients with differential somatic hypermutation status of the immunoglobulin heavy variable genes, namely mutated or unmutated, display fundamental clinico-biological differences. Considering this, we assessed prognosis separately within mutated (M-CLL) and unmutated (U-CLL) CLL in 3015 patients, hypothesizing that the relative significance of relevant indicators may differ between these two categories. Within Binet A M-CLL patients, besides TP53 abnormalities, trisomy 12 and stereotyped subset #2 membership were equivalently associated with the shortest time-to-first-treatment and a treatment probability at five and ten years after diagnosis of 40% and 55%, respectively; the remaining cases exhibited 5-year and 10-year treatment probability of 12% and 25%, respectively. Within Binet A U-CLL patients, besides TP53 abnormalities, del(11q) and/or SF3B1 mutations were associated with the shortest time-to-first-treatment (5- and 10-year treatment probability: 78% and 98%, respectively); in the remaining cases, males had a significantly worse prognosis than females. In conclusion, the relative weight of indicators that can accurately risk stratify early-stage CLL patients differs depending on the somatic hypermutation status of the immunoglobulin heavy variable genes of each patient. This finding highlights the fact that compartmentalized approaches based on immunogenetic features are necessary to refine and tailor prognostication in CLL.
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| 25. |
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| 26. |
- Bergh, Ann-Charlotte, et al.
(författare)
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Silenced B-cell receptor response to autoantigen in a poor-prognostic subset of chronic lymphocytic leukemia
- 2014
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Ingår i: Haematologica. - : Ferrata Storti Foundation. - 0390-6078 .- 1592-8721. ; 99:11, s. 1722-1730
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Tidskriftsartikel (refereegranskat)abstract
- Chronic lymphocytic leukemia B-cells express auto/xeno-antigen-reactive antibodies that bind to self-epitopes and resemble natural IgM antibodies in their repertoire. One of the antigenic structures recognized is oxidation-induced malonedialdehyde present on low-density lipoprotein, apoptotic blebs, and on certain microbes. The poor-prognostic stereotyped subset #1 (Clan I IGHV genes-IGKV1(D)-39) express IgM B-cell receptors that bind oxidized low-density lipoprotein. In this study, we have used for the first time this authentic cognate antigen, since it is more faithful to B-cell physiology than anti-IgM, for analysis of downstream B-cell receptor-signal transduction events. Multivalent oxidized low-density lipoprotein showed specific binding to subset #1 IgM/IgD B-cell receptors, whereas native low-density lipoprotein did not. The antigen-binding induced prompt receptor-clustering, followed by internalization. However, the receptor-signal transduction was silenced, revealing no Ca2+ mobilization or cell-cycle entry, while phosphorylated extracellular-regulated kinase1/2 basal levels were high and could not be elevated further by oxidized low-density lipoprotein. Interestingly, B-cell receptor responsiveness was recovered after 48 hours culture in the absence of antigen in half of the cases. Toll-like receptor 9-ligand was found to breach the B-cell receptor-signaling incompetence in 5 of 12 cases pointing to intra-subset heterogeneity. Altogether, this study supports B-cell receptor-unresponsiveness to cognate self-antigen on its own in poor-prognostic subset #1 chronic lymphocytic leukemia indicating that these cells proliferate by other mechanisms that may override B-cell receptor-silencing brought about in a context of self-tolerance/anergy. These novel findings have implications for the understanding of chronic lymphocytic leukemia pathobiology and therapy.
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| 27. |
- Bikos, Vasilis, et al.
(författare)
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An Immunogenetic Signature of Ongoing Antigen Interactions in Splenic Marginal Zone Lymphoma Expressing IGHV1-2*04 Receptors
- 2016
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Ingår i: Clinical Cancer Research. - 1078-0432 .- 1557-3265. ; 22:8, s. 2032-2040
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Tidskriftsartikel (refereegranskat)abstract
- Purpose: Prompted by the extensive biases in the immunoglobulin (IG) gene repertoire of splenic marginal-zone lymphoma (SMZL), supporting antigen selection in SMZL ontogeny, we sought to investigate whether antigen involvement is also relevant post-transformation. Experimental Design: We conducted a large-scale subcloning study of the IG rearrangements of 40 SMZL cases aimed at assessing intraclonal diversification (ID) due to ongoing somatic hypermutation (SHM). Results: ID was identified in 17 of 21 (81%) rearrangements using the immunoglobulin heavy variable (IGHV) 1-2*04 gene versus 8 of 19 (40%) rearrangements utilizing other IGHV genes (P = 0.001). ID was also evident in most analyzed IG light chain gene rearrangements, albeit was more limited compared with IG heavy chains. Identical sequence changes were shared by subclones from different patients utilizing the IGHV1-2*04 gene, confirming restricted ongoing SHM profiles. Non-IGHV1-2*04 cases displayed both a lower number of ongoing SHMs and a lack of shared mutations (per group of cases utilizing the same IGHV gene). Conclusions: These findings support ongoing antigen involvement in a sizable portion of SMZL and further argue that IGHV1-2*04 SMZL may represent a distinct molecular subtype of the disease.
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| 28. |
- Blanco, Gonzalo, et al.
(författare)
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Karyotypic complexity rather than chromosome 8 abnormalities aggravates the outcome of chronic lymphocytic leukemia patients with TP53 aberrations
- 2016
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Ingår i: Oncotarget. - : Impact Journals, LLC. - 1949-2553. ; 7:49, s. 80916-80924
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Tidskriftsartikel (refereegranskat)abstract
- Patients with chronic lymphocytic leukemia (CLL) harboring TP53 aberrations (TP53abs; chromosome 17p deletion and/or TP53 mutation) exhibit an unfavorable clinical outcome. Chromosome 8 abnormalities, namely losses of 8p (8p-) and gains of 8q (8q+) have been suggested to aggravate the outcome of patients with TP53abs. However, the reported series were small, thus hindering definitive conclusions. To gain insight into this issue, we assessed a series of 101 CLL patients harboring TP53 disruption. The frequency of 8p- and 8q+ was 14.7% and 17.8% respectively. Both were associated with a significantly (P < 0.05) higher incidence of a complex karyotype (CK, >= 3 abnormalities) detected by chromosome banding analysis (CBA) compared to cases with normal 8p (N-8p) and 8q (N-8q), respectively. In univariate analysis for 10- year overall survival (OS), 8p- (P = 0.002), 8q+ (P = 0.012) and CK (P = 0.009) were associated with shorter OS. However, in multivariate analysis only CK (HR = 2.47, P = 0.027) maintained independent significance, being associated with a dismal outcome regardless of chromosome 8 abnormalities. In conclusion, our results highlight the association of chromosome 8 abnormalities with CK amongst CLL patients with TP53abs, while also revealing that CK can further aggravate the prognosis of this aggressive subgroup.
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| 29. |
- Bonfiglio, Silvia, et al.
(författare)
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BTK and PLCG2 remain unmutated in one-third of patients with CLL relapsing on ibrutinib
- 2023
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Ingår i: Blood Advances. - : American Society of Hematology. - 2473-9529 .- 2473-9537. ; 7:12, s. 2794-2806
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Tidskriftsartikel (refereegranskat)abstract
- Patients with chronic lymphocytic leukemia (CLL) progressing on ibrutinib constitute an unmet need. Though Bruton tyrosine kinase (BTK) and PLCG2 mutations are associated with ibrutinib resistance, their frequency and relevance to progression are not fully understood. In this multicenter retrospective observational study, we analyzed 98 patients with CLL on ibrutinib (49 relapsing after an initial response and 49 still responding after ≥1 year of continuous treatment) using a next-generation sequencing (NGS) panel (1% sensitivity) comprising 13 CLL-relevant genes including BTK and PLCG2. BTK hotspot mutations were validated by droplet digital polymerase chain reaction (ddPCR) (0.1% sensitivity). By integrating NGS and ddPCR results, 32 of 49 relapsing cases (65%) carried at least 1 hotspot BTK and/or PLCG2 mutation(s); in 6 of 32, BTK mutations were only detected by ddPCR (variant allele frequency [VAF] 0.1% to 1.2%). BTK/PLCG2 mutations were also identified in 6 of 49 responding patients (12%; 5/6 VAF <10%), of whom 2 progressed later. Among the relapsing patients, the BTK-mutated (BTKmut) group was enriched for EGR2 mutations, whereas BTK-wildtype (BTKwt) cases more frequently displayed BIRC3 and NFKBIE mutations. Using an extended capture-based panel, only BRAF and IKZF3 mutations showed a predominance in relapsing cases, who were enriched for del(8p) (n = 11; 3 BTKwt). Finally, no difference in TP53 mutation burden was observed between BTKmut and BTKwt relapsing cases, and ibrutinib treatment did not favor selection of TP53-aberrant clones. In conclusion, we show that BTK/PLCG2 mutations were absent in a substantial fraction (35%) of a real-world cohort failing ibrutinib, and propose additional mechanisms contributing to resistance.
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| 30. |
- Bystry, Vojtech, et al.
(författare)
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ARResT/AssignSubsets : a novel application for robust subclassification of chronic lymphocytic leukemia based on B cell receptor IG stereotypy
- 2015
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Ingår i: Bioinformatics. - : Oxford University Press (OUP). - 1367-4803 .- 1367-4811. ; 31:23, s. 3844-3846
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Tidskriftsartikel (refereegranskat)abstract
- Motivation: An ever-increasing body of evidence supports the importance of B cell receptor immunoglobulin (BcR IG) sequence restriction, alias stereotypy, in chronic lymphocytic leukemia (CLL). This phenomenon accounts for similar to 30% of studied cases, one in eight of which belong to major subsets, and extends beyond restricted sequence patterns to shared biologic and clinical characteristics and, generally, outcome. Thus, the robust assignment of new cases to major CLL subsets is a critical, and yet unmet, requirement. Results: We introduce a novel application, ARResT/AssignSubsets, which enables the robust assignment of BcR IG sequences from CLL patients to major stereotyped subsets. ARResT/AssignSubsets uniquely combines expert immunogenetic sequence annotation from IMGT/V-QUEST with curation to safeguard quality, statistical modeling of sequence features from more than 7500 CLL patients, and results from multiple perspectives to allow for both objective and subjective assessment. We validated our approach on the learning set, and evaluated its real-world applicability on a new representative dataset comprising 459 sequences from a single institution.
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| 31. |
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| 32. |
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| 33. |
- Chatzouli, Maria, et al.
(författare)
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Heterogeneous Functional Effects of Concomitant B Cell Receptor and TLR Stimulation in Chronic Lymphocytic Leukemia with Mutated versus Unmutated Ig Genes
- 2014
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Ingår i: Journal of Immunology. - : The American Association of Immunologists. - 0022-1767 .- 1550-6606. ; 192:10, s. 4518-4524
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Tidskriftsartikel (refereegranskat)abstract
- We recently reported that chronic lymphocytic leukemia (CLL) subgroups with distinct clonotypic BCRs present discrete patterns of TLR expression, function, and/ or tolerance. In this study, to explore whether specific types of BCR/TLR collaboration exist in CLL, we studied the effect of single versus concomitant BCR and/or TLR stimulation on CLL cells from mutated (M-CLL) and unmutated CLL (U-CLL) cases. We stimulated negatively isolated CLL cells by using anti-IgM, imiquimod, and CpG oligodeoxynucleotide for BCR, TLR7, and TLR9, respectively, alone or in combination for different time points. After in vitro culture in the absence of stimulation, differences in p-ERK were identified at any time point, with higher p-ERK levels in U-CLL versus M-CLL. Pronounced p-ERK induction was seen by single stimulation in U-CLL, whereas BCR/TLR synergism was required in M-CLL, in which the effect was overall limited in scale. An opposite pattern was observed regarding induction of apoptosis, as studied by Western blotting for the cleaved fragment of poly(ADP-ribose) polymerase, and the active isoform of caspase-8, with M-CLL responding even to single stimulation, contrasting with U-CLL that showed minimal response. Our findings suggest that concomitant engagement of BCR and TLR leads to differential responses in CLL depending on the mutational status of the BCR. Differential intensity and duration of responses in M-CLL versus U-CLL indicates that the differences in signal transduction between the two subgroups may be primarily quantitative rather than qualitative.
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| 34. |
- Chigrinova, Ekaterina, et al.
(författare)
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Two main genetic pathways lead to the transformation of chronic lymphocytic leukemia to Richter syndrome
- 2013
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Ingår i: Blood. - : American Society of Hematology. - 0006-4971 .- 1528-0020. ; 122:15, s. 2673-2682
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Tidskriftsartikel (refereegranskat)abstract
- Richter syndrome (RS) occurs in up to 15% of patients with chronic lymphocytic leukemia (CLL). Although RS, usually represented by the histologic transformation to a diffuse large B-cell lymphoma (DLBCL), is associated with a very poor outcome, especially when clonally related to the preexisting CLL, the mechanisms leading to RS have not been clarified. To better understand the pathogenesis of RS, we analyzed a series of cases including 59 RS, 28 CLL phase of RS, 315 CLL, and 127 de novo DLBCL. RS demonstrated a genomic complexity intermediate between CLL and DLBCL. Cell-cycle deregulation via inactivation of TP53 and of CDKN2A was a main mechanism in the histologic transformation from CLL phase, being present in approximately one half of the cases, and affected the outcome of the RS patients. A second major subgroup was characterized by the presence of trisomy 12 and comprised one third of the cases. Although RS shared some of the lesions seen in de novo DLBCL, its genomic profile was clearly separate. The CLL phase preceding RS had not a generalized increase in genomic complexity compared with untransformed CLL, but it presented clear differences in the frequency of specific genetic lesions.
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| 35. |
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| 36. |
- Engert, Andreas, et al.
(författare)
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The European Hematology Association Roadmap for European Hematology Research : a consensus document
- 2016
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Ingår i: Haematologica. - Pavia, Italy : Ferrata Storti Foundation (Haematologica). - 0390-6078 .- 1592-8721. ; 101:2, s. 115-208
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Tidskriftsartikel (refereegranskat)abstract
- The European Hematology Association (EHA) Roadmap for European Hematology Research highlights major achievements in diagnosis and treatment of blood disorders and identifies the greatest unmet clinical and scientific needs in those areas to enable better funded, more focused European hematology research. Initiated by the EHA, around 300 experts contributed to the consensus document, which will help European policy makers, research funders, research organizations, researchers, and patient groups make better informed decisions on hematology research. It also aims to raise public awareness of the burden of blood disorders on European society, which purely in economic terms is estimated at (sic)23 billion per year, a level of cost that is not matched in current European hematology research funding. In recent decades, hematology research has improved our fundamental understanding of the biology of blood disorders, and has improved diagnostics and treatments, sometimes in revolutionary ways. This progress highlights the potential of focused basic research programs such as this EHA Roadmap. The EHA Roadmap identifies nine 'sections' in hematology: normal hematopoiesis, malignant lymphoid and myeloid diseases, anemias and related diseases, platelet disorders, blood coagulation and hemostatic disorders, transfusion medicine, infections in hematology, and hematopoietic stem cell transplantation. These sections span 60 smaller groups of diseases or disorders. The EHA Roadmap identifies priorities and needs across the field of hematology, including those to develop targeted therapies based on genomic profiling and chemical biology, to eradicate minimal residual malignant disease, and to develop cellular immunotherapies, combination treatments, gene therapies, hematopoietic stem cell treatments, and treatments that are better tolerated by elderly patients.
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| 37. |
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| 38. |
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| 39. |
- Ghia, Paolo, et al.
(författare)
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Crystallographic evidence of autologous recognition by a clonotypic B cell receptor in chronic lymphocytic leukemia
- 2015
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Ingår i: Leukemia and Lymphoma. - IRCCS Sci Inst San Raffaele, Div Expt Oncol, Milan, Italy. [Degano, Massimo] IRCCS Sci Inst San Raffaele, Dept Immunol Transplantat & Infect Dis, Biocrystallog Unit, Milan, Italy. [Duehren-von Minden, Marcus; Schneider, Dunja; Alkhatib, Alabbas] Univ Freiburg, Ctr Biol Signaling Studies, Fac Biol, D-79106 Freiburg, Germany. [Belhart, Rudolf; Jumaa, Hassan] Univ Ulm Klinikum, Ulm, Germany. [Ntoufa, Stavroula; Stamatopoulos, Kostas] Ctr Res & Technol, Inst Appl Biosci, Thessaloniki, Greece. [Chiorazzi, Nicholas] Feinstein Inst Med Res, Manhasset, NY USA. [Stamatopoulos, Kostas] Uppsala Univ, Dept Immunol Genet & Pathol, Uppsala, Sweden. [Ghia, Paolo] Univ Milan, Osped San Raffaele, Dept Oncohematol, I-20127 Milan, Italy. [Ghia, Paolo] Univ Vita Salute San Raffaele, Milan, Italy.. - 1042-8194 .- 1029-2403. ; 56:S1, s. 110-111
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Tidskriftsartikel (övrigt vetenskapligt/konstnärligt)
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| 40. |
- Ghia, P., et al.
(författare)
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Early stages in the ontogeny of small B-cell lymphomas : genetics and microenvironment
- 2017
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Ingår i: Journal of Internal Medicine. - : Wiley. - 0954-6820 .- 1365-2796. ; 282:5, s. 395-414
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Tidskriftsartikel (refereegranskat)abstract
- In this review, we focus on the mechanisms underlying lymphomagenesis in chronic lymphocytic leukaemia, follicular lymphoma, mantle cell lymphoma and splenic marginal zone lymphoma. The cells of origin of these small B-cell lymphomas are distinct, as are the characteristic chromosomal lesions and clinical courses. One shared feature is retention of expression of surface immunoglobulin. Analysis of this critical receptor reveals the point of differentiation reached by the cell of origin. Additionally, the sequence patterns of the immunoglobulin-variable domains can indicate a role for stimulants of the B-cell receptor before, during and after malignant transformation. The pathways driven via the B-cell receptor are now being targeted by specific kinase inhibitors with exciting clinical effects. To consider routes to pathogenesis, potentially offering earlier intervention, or to identify causative factors, genetic tools are being used to track pretransformation events and the early phases in lymphomagenesis. These methods are revealing that chromosomal changes are only one of the many steps involved, and that the influence of surrounding cells, probably multiple and variable according to tissue location, is required, both to establish tumours and to maintain growth and survival. Similarly, the influence of the tumour microenvironment may protect malignant cells from eradication by treatment, and the resulting minimal residual disease will eventually give rise to relapse. The common and different features of the four lymphomas will be summarized to show how normal B lymphocytes can be subverted to generate tumours, how these tumours evolve and how their weaknesses can be attacked by targeted therapies.
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| 41. |
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| 42. |
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| 43. |
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| 44. |
- Gounari, Maria, et al.
(författare)
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Excessive antigen reactivity may underlie the clinical aggressiveness of chronic lymphocytic leukemia stereotyped subset #8
- 2015
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Ingår i: Blood. - : American Society of Hematology. - 0006-4971 .- 1528-0020. ; 125:23, s. 3580-3587
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Tidskriftsartikel (refereegranskat)abstract
- Subset #8 is a distinctive subset of patients with chronic lymphocytic leukemia (CLL) defined by the expression of stereotyped IGHV4-39/IGKV1(D)-39 B-cell receptors. Subset #8 patients experience aggressive disease and exhibit the highest risk for Richter transformation among all CLL. In order to obtain biological insight into this behavior, we profiled the antigen reactivity and signaling capacity of subset #8 vs other clinically aggressive stereotyped subsets, namely subsets #1 and #2. Twenty-seven monoclonal antibodies (mAbs) from subsets #1, #2, and #8 CLL clones were prepared as recombinant human immunoglobulin G1 and used as primary antibodies in enzyme-linked immuno-sorbent assays against representatives of the major classes of established antigenic targets for CLL. Subset #8 CLL mAbs exhibited broad polyreactivity as they bound to all antigens tested, in clear contrast with the mAbs from the other subsets. Antigen challenge of primary CLL cells indicated that the promiscuous antigen-binding activity of subset #8 mAbs could lead to significant cell activation, again in contrast to the less responsive CLL cells from subsets #1 and #2. These features constitute a distinctive profile for CLL subset #8, supporting the existence of distinct mechanisms of aggressiveness in different immunogenetic subsets of CLL.
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| 45. |
- Hadzidimitriou, Anastasia, et al.
(författare)
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Evidence for the significant role of immunoglobulin light chains in antigen recognition and selection in chronic lymphocytic leukemia
- 2009
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Ingår i: Blood. - : American Society of Hematology. - 0006-4971 .- 1528-0020. ; 113:2, s. 403-411
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Tidskriftsartikel (refereegranskat)abstract
- We analyzed somatic hypermutation (SHM) patterns and secondary rearrangements involving the immunoglobulin (IG) light chain (LC) gene loci in 725 patients with chronic lymphocytic leukemia (CLL). Important differences regarding mutational load and targeting were identified in groups of sequences defined by IGKV/IGLV gene usage and/or K/LCDR3 features. Recurrent amino acid (AA) changes in the IGKV/IGLV sequences were observed in subsets of CLL cases with stereotyped B-cell receptors (BCRs), especially those expressing IGHV3-21/IGLV3-21 and IGHV4-34/IGKV2-30 BCRs. Comparison with CLL LC sequences carrying heterogeneous K/LCDR3s or non-CLL LC sequences revealed that distinct amino acid changes appear to be "CLL-biased." Finally, a significant proportion of CLL cases with monotypic LC expression were found to carry multiple potentially functional LC rearrangements, alluding to active, (auto) antigen-driven receptor editing. In conclusion, SHM targeting in CLL LCs is just as precise and, likely, functionally driven as in heavy chains. Secondary LC gene rearrangements and subset-biased mutations in CLL LC genes are strong indications that LCs are crucial in shaping the specificity of leukemic BCRs, in association with defined heavy chains. Therefore, CLL is characterized not only by stereotyped HCDR3 and heavy chains but, rather, by stereotyped BCRs involving both chains, which generate distinctive antigen-binding grooves.
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| 46. |
- Hadzidimitriou, Anastasia, et al.
(författare)
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Is there a role for antigen selection in mantle cell lymphoma? : Immunogenetic support from a series of 807 cases
- 2011
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Ingår i: Blood. - : American Society of Hematology. - 0006-4971 .- 1528-0020. ; 118:11, s. 3088-3095
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Tidskriftsartikel (refereegranskat)abstract
- We examined 807 productive IGHV-IGHD-IGHJ gene rearrangements from mantle cell lymphoma (MCL) cases, by far the largest series to date. The IGHV gene repertoire was remarkably biased, with IGHV3-21, IGHV4-34, IGHV1-8, and IGHV3-23 accounting for 46.3% of the cohort. Eighty-four of 807 (10.4%) cases, mainly using the IGHV3-21 and IGHV4-34 genes, were found to bear stereotyped heavy complementarity-determining region 3 (VH CDR3) sequences and were placed in 38 clusters. Notably, the MCL stereotypes were distinct from those reported for chronic lymphocytic leukemia. Based on somatic hypermutation (SHM) status, 238/807 sequences (29.5%) carried IGHV genes with 100% germ line identity; the remainder (569/807; 70.5%) exhibited different SHM impact, ranging from minimal (in most cases) to pronounced. Shared replacement mutations across the IGHV gene were identified for certain subgroups, especially those using IGHV3-21, IGHV1-8, and IGHV3-23. Comparison with other entities, in particular CLL, revealed that several of these mutations were "MCL-biased." In conclusion, MCL is characterized by a highly restricted immunoglobulin gene repertoire with stereotyped VH CDR3s and very precise SHM targeting, strongly implying a role for antigen-driven selection of the clonogenic progenitors. Hence, an antigen-driven origin of MCL could be envisaged, at least for subsets of cases.
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| 47. |
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| 48. |
- Halldorsdottir, Anna Margret, et al.
(författare)
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Mantle cell lymphoma displays a homogenous methylation profile : A comparative analysis with chronic lymphocytic leukemia
- 2012
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Ingår i: American Journal of Hematology. - : John Wiley & Sons. - 0361-8609 .- 1096-8652. ; 87:4, s. 361-367
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Tidskriftsartikel (refereegranskat)abstract
- Mantle cell lymphoma (MCL) and chronic lymphocytic leukemia (CLL) are mature CD5(+) B-cell malignancies with different biological/clinical characteristics. We recently reported an association between different prognostic subgroups of CLL (i.e., IGHV mutated and unmutated) and genomic methylation pattern. However, the relationship between DNA methylation and prognostic markers, such as the proliferation gene expression signature, has not been investigated in MCL. We applied high-resolution methylation microarrays (27,578 CpG sites) to assess the global DNA methylation profiles in 20 MCL (10 each with high/low proliferation signature) and 30 CLL (15 poor-prognostic IGHV unmutated subset #1 and 15 good-prognostic IGHV mutated subset #4) samples. Notably, MCL and each CLL subset displayed distinct genomic methylation profiles. After unsupervised hierarchical clustering, 17/20 MCL cases formed a cluster separate from CLL, while CLL subsets #1 and #4 formed subclusters. Surprisingly, few differentially methylated genes (n = 6) were identified between high vs. low proliferation MCL. In contrast, distinct methylation profiles were demonstrated for MCL and CLL. Importantly, certain functional classes of genes were preferentially methylated in either disease. For instance, developmental genes, in particular homeobox transcription factor genes (e.g., HLXB9, HOXA13), were more highly methylated in MCL, whereas apoptosis-related genes were enriched among targets methylated in CLL (e.g., CYFIP2, NR4A1). Results were validated using pyrosequencing, RQ-PCR and reexpression of specific genes. In summary, the methylation profile of MCL was homogeneous and no correlation with the proliferation signature was observed. Compared to CLL, however, marked differences were discovered such as the preferential methylation of homeobox genes in MCL.
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| 49. |
- Halldorsdottir, Anna Margret, et al.
(författare)
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Mantle cell lymphoma displays a homogenous methylation profile: A comparative analysis with chronic lymphocytic leukemia
- 2012
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Ingår i: American Journal of Hematology. - : Wiley. - 0361-8609 .- 1096-8652. ; 87:4, s. 361-367
-
Tidskriftsartikel (refereegranskat)abstract
- Mantle cell lymphoma (MCL) and chronic lymphocytic leukemia (CLL) are mature CD5(+) B-cell malignancies with different biological/clinical characteristics. We recently reported an association between different prognostic subgroups of CLL (i.e., IGHV mutated and unmutated) and genomic methylation pattern. However, the relationship between DNA methylation and prognostic markers, such as the proliferation gene expression signature, has not been investigated in MCL. We applied high-resolution methylation microarrays (27,578 CpG sites) to assess the global DNA methylation profiles in 20 MCL (10 each with high/low proliferation signature) and 30 CLL (15 poor-prognostic IGHV unmutated subset #1 and 15 good-prognostic IGHV mutated subset #4) samples. Notably, MCL and each CLL subset displayed distinct genomic methylation profiles. After unsupervised hierarchical clustering, 17/20 MCL cases formed a cluster separate from CLL, while CLL subsets #1 and #4 formed subclusters. Surprisingly, few differentially methylated genes (n = 6) were identified between high vs. low proliferation MCL. In contrast, distinct methylation profiles were demonstrated for MCL and CLL. Importantly, certain functional classes of genes were preferentially methylated in either disease. For instance, developmental genes, in particular homeobox transcription factor genes (e.g., HLXB9, HOXA13), were more highly methylated in MCL, whereas apoptosis-related genes were enriched among targets methylated in CLL (e.g., CYFIP2, NR4A1). Results were validated using pyrosequencing, RQ-PCR and reexpression of specific genes. In summary, the methylation profile of MCL was homogeneous and no correlation with the proliferation signature was observed. Compared to CLL, however, marked differences were discovered such as the preferential methylation of homeobox genes in MCL. Am. J. Hematol., 2012. (C) 2012 Wiley Periodicals, Inc.
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| 50. |
- Ioannou, Nikolaos, et al.
(författare)
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Triggering interferon signaling in T cells with avadomide sensitizes CLL to anti-PD-L1 /PD-1 immunotherapy
- 2021
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Ingår i: Blood. - : American Society of Hematology. - 0006-4971 .- 1528-0020. ; 137:2, s. 216-231
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Tidskriftsartikel (refereegranskat)abstract
- Cancer treatment has been transformed by checkpoint blockade therapies, with the highest anti-tumor activity of anti-programmed death 1 (PD-1) antibody therapy seen in Hodgkin lymphoma. Disappointingly, response rates have been low in the non-Hodgkin lymphomas, with no activity seen in relapsed/refractory chronic lymphocytic leukemia (CLL) with PD-1 blockade. Thus, identifying more powerful combination therapy is required for these patients. Here, we preclinically demonstrate enhanced anti-CLL activity following combinational therapy with anti-PD-1 or anti-PD-1 ligand (PD-L1) and avadomide, a cereblon E3 ligase modulator (CELMoD). Avadomide induced type I and II interferon (IFN) signaling in patient T cells, triggering a feedforward cascade of reinvigorated T-cell responses. Immune modeling assays demonstrated that avadomide stimulated T-cell activation, chemokine expression, motility and lytic synapses with CLL cells, as well as IFN-inducible feedback inhibition through upregulation of PD-L1. Patient-derived xenograft tumors treated with avadomide were converted to CD8(+) T cell-inflamed tumor microenvironments that responded to anti-PD-L1/PD-1-based combination therapy. Notably, clinical analyses showed increased PD-L1 expression on T cells, as well as intratumoral expression of chemokine signaling genes in B-cell malignancy patients receiving avadomide-based therapy. These data of overcoming a low inflammatory T-cell state to successfully sensitize CLL to checkpoint illustrate the importance blockade-based combination therapy.
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