scholarly journals Downregulation of Mir-142 Promotes Leukemia Growth in Philadelphia Chromosome-Positive (Ph+) Acute Lymphoblastic Leukemia (ALL): A Possible Novel Therapeutic Target?

Blood ◽  
2018 ◽  
Vol 132 (Supplement 1) ◽  
pp. 1338-1338
Author(s):  
Huafeng Wang ◽  
Bin Zhang ◽  
Wei-Le Wang ◽  
Dandan Zhao ◽  
Ling Li ◽  
...  
Keyword(s):  
Cell Differentiation ◽  
Tyrosine Kinase ◽  
B Cell ◽  
Median Survival ◽  
Lymphoblastic Leukemia ◽  
Rapid Expansion ◽  
B Cell Differentiation ◽  
Hematopoietic Stem ◽  
Knock Out ◽  
Healthy Donors

Abstract The Philadelphia (Ph) chromosome or t(9;22) results in the generation of a fusion gene, namely BCR/ABL1, which encodes a chimeric protein with aberrant tyrosine kinase activity that drives leukemia cell growth and survival. This molecular/cytogenetic aberration occurs in ~20%-30% of ALL cases and confers poor prognosis. Ph+ ALL patients (pts) are often referred for allogeneic hematopoietic stem cell transplantation (alloHCT), although more recently BCR-ABL-specific tyrosine-kinase inhibitors (TKIs) and immunotherapeutic approaches seemingly induced long-term remission in some patients. Nevertheless, it is still a challenge to determine which Ph+ ALL of the pts could be treated more conservatively without alloHCT. Thus identification of new prognostic biomarkers and/or therapeutic targets may be helpful. Regulation of short non-coding microRNAs(miRNAs) associated with initiation and progression of acute leukemia has been reported. miR-142(both miR-142-3p and miR-142-5p) is expressed at a relatively high level in hematopoietic tissue, and plays a role in myeloid lineage differentiation. In fact, low miR-142-3p expression was associated with myeloid differentiation failure, and miR-142 mutations was reported to promote acute myeloid leukemia (AML). More recently, Kramer et al demonstrated a role of miR-142 in lymphopoiesis by showing that miR-142 deficiency impaired B cell production in a miR-142 knock-out(ko) mouse model (Blood. 2015). Here, we first investigated if miR-142 levels were altered in ALL pts. Analysis of a publically available miRNA expression dataset(GSE23024) showed lower level of miR-142-3p, but not miR-142-5p in Ph+ ALL pts(n=10) vs. healthy donors(n=7;p=0.0093); while no significant differences were observed in Ph- pre-B ALL pts(n=61) vs. healthy donors (n=7). In ALL Tg(P190-BCR/ABL) transgenic mice(Ph+ ALL; Nature. 1990), we found bone marrow (BM) miR-142-3p level to be ~2.3-fold lower than those in the wild-type (wt) controls(p=0.036). Compared to wt mice, Ph+ ALL mice showed significantly lower miR-142-3p level in all the immunophenotypically identified BM lymphoid subpopulations, including progenitor B (pro-B, B220+CD19+CD43+IgM-,~19.1-fold lower,p<0.0001), precursor B (pre-B, B220+CD19+CD43-IgM-,~9.7-fold lower, p<0.0001), and other immature B (B220lowCD19+CD43-IgM+, ~2.4-fold lower, p<0.001) cells, except for mature B (B220highCD19+CD43-IgM+) cells. Ph+ ALL mice exhibited a miR-142-3p gradient expression pattern following the lymphoid differentiation hierarchy, with the lowest levels found in the pro-B and pre-B populations. These results prompted us to hypothesize that, loss of miR-142 may contribute to primitive B cell expansion possibly due to B cell differentiation blockage in Ph+ ALL mice. To prove this, we crossed miR-142 double knock-out (d-ko)mice with Ph+ ALL mice to generate miR-142(ko)Tg(P190-BCR/ABL) mice. Homozygous miR-142(d-ko)Tg(P190-BCR/ABL) mice were not viable due to an overly aggressive leukemia phenotype. Heterozygous miR-142(wt/ko)Tg(P190-BCR/ABL) mice had evidence of more rapid expansion of pro-B cells in blood(PB; 47.9% vs. 9.8%, p<0.0001), BM (48.2% vs. 13.2%, p<0.01)and spleen(32.3%vs. 4.4%, p<0.01) at 6 weeks old and a significantly reduced survival(median survival 44 vs.80 days, p<0.0001), compared to miR-142(wt/wt)Tg(P190-BCR/ABL) controls. BM cells (CD45.2) from miR-142(wt/ko)Tg(P190-BCR/ABL) mice (n=4) or miR-142(wt/wt)Tg(P190-BCR/ABL) mice (n=5) were then transplanted into congenic CD45.1 recipient mice (n=18 and n=15 respectively).Recipients of BM cells from miR-142(wt/ko)Tg(P190-BCR/ABL) donors showed increased engraftment (94% vs. 77% in PB at 4 weeks, p<0.0001) and significantly reduced survival(median survival 25 vs. 49 days, p<0.0001), as compared with recipients of BM cells from miR-142(wt/wt)P190-BCR-ABL mice. Finally, upon ex vitro exposure to the TKI nilotinib (5uM for 48 hours), miR-142(wt/ko)Tg(P190-BCR/ABL) BM cells showed reduced apoptosis (7.0% vs.37.5% vs p<0.05) and increased cell viability (66% vs.16.2%, p<0.05) compared with miR-142 (wt/wt)Tg(P190-BCR/ABL) BM cells. In vivo treatment studies with TKI treatment are ongoing and data will be presented at the meeting. In conclusion, miR-142 downregulation promotes rapid Ph+ ALL growth likely by contributing to a blockage of B cell differentiation, and may mediate resistance to TKIs. Disclosures Stein: Celgene: Speakers Bureau; Amgen Inc.: Speakers Bureau. Jin:The National Natural Science Foundation of China: Research Funding; College of Medicine, Zhejiang University: Employment.

The Linker Protein GAS7 Negatively Regulates Pre-B Cell Differentiation and Amplifies Proliferation and Survival Signals in Acute Lymphoblastic Leukemia

Blood ◽  
2014 ◽  
Vol 124 (21) ◽  
pp. 3777-3777 ◽  
Author(s):  
Jae-Woong Lee ◽  
Maike Buchner ◽  
Huimin Geng ◽  
Srividya Swaminathan ◽  
Eugene Park ◽  
...  
Keyword(s):  
Cell Differentiation ◽  
Acute Lymphoblastic Leukemia ◽  
B Cells ◽  
Tyrosine Kinase ◽  
B Cell ◽  
Lymphoblastic Leukemia ◽  
Growth Arrest ◽  
Strong Increase ◽  
Fusion Partner ◽  
B Cell Differentiation

Abstract Background: Growth arrest-specific gene 7 (Gas7) functions as an adaptor for SH2- and SH3-containing proteins, in particular in cells that undergo growth arrest. Gas7 is abundantly expressed in the brain and is involved in neuronal differentiation. Interestingly, MLL-GAS7 fusion molecules resulting from the t(11;17)(q23;p13) chromosomal translocation have been reported in treatment-related acute myeloid leukemia (AML; Megonigal et al., 2000) and in a pediatric acute lymphoblastic leukemia (ALL). While the function of MLL has been extensively studied, the role of its fusion partner GAS7 in normal hematopoiesis and leukemia has not been elucidated. Results: Studying gene expression changes during normal B cell development, we identified Gas7 as the gene with the strongest relative increase at the pre-B cell receptor checkpoint. At the transition from IL7-dependent Fraction C’ to IL7-independent small resting pre-B cells (Fraction D), GAS7 mRNA levels were upregulated by >13-fold in both human and mouse B cell progenitors. Withdrawal of IL7 cytokine signaling and Cre-mediated conditional deletion of Stat5ab recapitulated the strong increase of GAS7 expression under cell culture conditions. These finding suggest that GAS7 is part of an adaptive response of differentiating pre-B cells to attenuation of cytokine/Stat5 signaling. Consistent with this scenario, we found that Gas7-/-pre-B cells undergo accelerated differentiation, including spontaneous Ig κ light chain gene recombination and loss of Stat5-signaling. Conversely, overexpression of GAS7, reduced responsiveness of pre-B cells to normal differentiation stimuli. These findings suggest that the linker molecule GAS7 is a negative regulator of pre-B cell differentiation. Likewise, we found that tyrosine kinase inhibitor treatment of human Ph+ ALL cells resulted in a strong increased of GAS7 expression, in parallel with loss of Stat5 function. To elucidate the function of Gas7 in B cell lineage leukemia, we transformed bone marrow pre-B cells from Gas7-/- mice with BCR-ABL1. Gas7 deficient Ph+ ALL cells showed decreased proliferation with reduced S phase and increased apoptosis. In agreement with effects of Stat5 on the sensitivity of Ph+ ALL cells against tyrosine kinase inhibitors (TKIs), Gas7 deficient Ph+ ALL cells showed massively increased susceptibility to Imatinib-induced apoptosis. In addition, absence of Gas7 caused loss of self-renewal capacity and failure to form colonies in methylcellulose assay. Co-immunoprecipitation experiments with flag tagged GAS7 in patient-derived Ph+ALL cells revealed that GAS7 physically interacts with STAT5 and retains STAT5-Y694 in an active conformation.Thereby, GAS7 can propagate even weak Stat5 activity and maintain residual cytokine or BCR-ABL1 oncogenic signaling in normal and malignant pre-B cells. Conclusions: Here show that GAS7 functions as an important positive regulator of Stat5 downstream of cytokine receptors in normal pre-B cells and downstream of BCR-ABL1 and other oncogenes in leukemia. Owing to the GAS7-dependent reinforcement of Stat5-dependent survival and proliferation signaling, normal and leukemic pre-B cells can survive periods of reduced cytokine/oncogene signaling. These findings suggest that the interaction interface between GAS7 and Stat5 represents a potential target for small molecule scaffolds and peptides. Disclosures No relevant conflicts of interest to declare.

AB0144 STRATIFICATION OF PATIENTS WITH PRIMARY SJÖGREN’S SYNDROME BY MEASURING B-CELL HEALTH

2020 ◽  
Vol 79 (Suppl 1) ◽  
pp. 1372-1373
Author(s):  
G. M. Verstappen ◽  
J. C. Tempany ◽  
H. Cheon ◽  
A. Farchione ◽  
S. Downie-Doyle ◽  
...  
Keyword(s):  
Cell Division ◽  
Cell Differentiation ◽  
T Cell ◽  
B Cells ◽  
B Cell ◽  
B Cell Differentiation ◽  
Research Support ◽  
Differentiation Capacity ◽  
Cell Responses ◽  
Healthy Donors

Background:Primary Sjögren’s syndrome (pSS) is a heterogeneous immune disorder with broad clinical phenotypes that can arise from a large number of genetic, hormonal, and environmental causes. B-cell hyperactivity is considered to be a pathogenic hallmark of pSS. However, whether B-cell hyperactivity in pSS patients is a result of polygenic, B cell-intrinsic factors, extrinsic factors, or both, is unclear. Despite controversies about the efficacy of rituximab, new B-cell targeting therapies are under investigation with promising early results. However, for such therapies to be successful, the etiology of B-cell hyperactivity in pSS needs to be clarified at the individual patient level.Objectives:To measure naïve B-cell function in pSS patients and healthy donors using quantitative immunology.Methods:We have developed standardised, quantitative functional assays of B-cell responses that measure division, death, differentiation and isotype switching, to reveal the innate programming of B cells in response to T-independent and dependent stimuli. This novel pipeline to measure B-cell health was developed to reveal the sum total of polygenic defects and underlying B-cell dysfunction at an individual level. For the current study, 25 pSS patients, fulfilling 2016 ACR-EULAR criteria, and 15 age-and gender-matched healthy donors were recruited. Standardized quantitative assays were used to directly measure B cell division, death and differentiation in response to T cell-independent (anti-Ig + CpG) and T-cell dependent (CD40L + IL-21) stimuli. Naïve B cells (IgD+CD27-) were sorted from peripheral blood mononuclear cells and were labeled with Cell Trace Violet at day 0 to track cell division until day 6. B cell differentiation was measured at day 5.Results:Application of our standardized assays, and accompanying parametric models, allowed us to study B cell-intrinsic defects in pSS patients to a range of stimuli. Strikingly, we demonstrated a hyperresponse of naïve B cells to combined B cell receptor (BCR) and Toll-like receptor (TLR)-9 stimulation in pSS patients. This hyperresponse was revealed by an increased mean division number (MDN) at day 5 in pSS patients compared with healthy donors (p=0.021). A higher MDN in pSS patients was observed at the cohort level and was likely attributed to an increased division burst (division destiny) time. The MDN upon BCR/TLR-9 stimulation correlated with serum IgG levels (rs=0.52; p=0.011). No difference in MDN of naïve B cells after T cell-dependent stimulation was observed between pSS patients and healthy donors. B cell differentiation capacity (e.g., plasmablast formation and isotype switching) after T cell-dependent stimulation was also assessed. At the cohort level, no difference in differentiation capacity between groups was observed, although some pSS patients showed higher plasmablast frequencies than healthy donors.Conclusion:Here, we demonstrate defects in B-cell responses both at the cohort level, as well as individual signatures of defective responses. Personalized profiles of B cell health in pSS patients reveal a group of hyperresponsive patients, specifically to combined BCR/TLR stimulation. These patients may benefit most from B-cell targeted therapies. Future studies will address whether profiles of B cell health might serve additional roles, such as prediction of disease trajectories, and thus accelerate early intervention and access to precision therapies.Disclosure of Interests:Gwenny M. Verstappen: None declared, Jessica Catherine Tempany: None declared, HoChan Cheon: None declared, Anthony Farchione: None declared, Sarah Downie-Doyle: None declared, Maureen Rischmueller Consultant of: Abbvie, Bristol-Meyer-Squibb, Celgene, Glaxo Smith Kline, Hospira, Janssen Cilag, MSD, Novartis, Pfizer, Roche, Sanofi, UCB, Ken R. Duffy: None declared, Frans G.M. Kroese Grant/research support from: Unrestricted grant from Bristol-Myers Squibb, Consultant of: Consultant for Bristol-Myers Squibb, Speakers bureau: Speaker for Bristol-Myers Squibb, Roche and Janssen-Cilag, Hendrika Bootsma Grant/research support from: Unrestricted grants from Bristol-Myers Squibb and Roche, Consultant of: Consultant for Bristol-Myers Squibb, Roche, Novartis, Medimmune, Union Chimique Belge, Speakers bureau: Speaker for Bristol-Myers Squibb and Novartis., Philip D. Hodgkin Grant/research support from: Medimmune, Vanessa L. Bryant Grant/research support from: CSL

Regulation of CCR6 chemokine receptor expression and responsiveness to macrophage inflammatory protein-3α/CCL20 in human B cells

Blood ◽  
2000 ◽  
Vol 96 (7) ◽  
pp. 2338-2345 ◽  
Author(s):  
Roman Krzysiek ◽  
Eric A. Lefevre ◽  
Jérôme Bernard ◽  
Arnaud Foussat ◽  
Pierre Galanaud ◽  
...  
Keyword(s):  
Cell Differentiation ◽  
B Cells ◽  
B Cell ◽  
Chemokine Receptor ◽  
Memory B Cells ◽  
Receptor Expression ◽  
B Cell Differentiation ◽  
Hematopoietic Stem ◽  
Inflammatory Protein ◽  
Macrophage Inflammatory Protein

Abstract The regulation of CCR6 (chemokine receptor 6) expression during B-cell ontogeny and antigen-driven B-cell differentiation was analyzed. None of the CD34+Lin− hematopoietic stem cell progenitors or the CD34+CD19+ (pro-B) or the CD19+CD10+ (pre-B/immature B cells) B-cell progenitors expressed CCR6. CCR6 is acquired when CD10 is lost and B-cell progeny matures, entering into the surface immunoglobulin D+ (sIgD+) mature B-cell pool. CCR6 is expressed by all bone marrow–, umbilical cord blood–, and peripheral blood–derived naive and/or memory B cells but is absent from germinal center (GC) B cells of secondary lymphoid organs. CCR6 is down-regulated after B-cell antigen receptor triggering and remains absent during differentiation into immunoglobulin-secreting plasma cells, whereas it is reacquired at the stage of post-GC memory B cells. Thus, within the B-cell compartment, CCR6 expression is restricted to functionally mature cells capable of responding to antigen challenge. In transmigration chemotactic assays, macrophage inflammatory protein (MIP)-3α/CC chemokine ligand 20 (CCL20) induced vigorous migration of B cells with differential chemotactic preference toward sIgD− memory B cells. These data suggest that restricted patterns of CCR6 expression and MIP-3α/CCL20 responsiveness are integral parts of the process of B-lineage maturation and antigen-driven B-cell differentiation.

A Critical Role of Blockade of Cell Differentiation in BCR-ABL-Induced B-Cell Acute Lymphoblastic Leukemia (B-ALL): Basis for Superb Therapeutic Effect on B-ALL in Mice by Promotion of Pro-B Leukemic Cell Differentiation and Treatment with Imatinib.

Blood ◽  
2005 ◽  
Vol 106 (11) ◽  
pp. 844-844
Author(s):  
Yiguo Hu ◽  
Linghong Kong ◽  
Kevin Staples ◽  
Kevin Mills ◽  
John G. Monroe ◽  
...  
Keyword(s):  
Cell Differentiation ◽  
Acute Lymphoblastic Leukemia ◽  
B Cell ◽  
Myeloid Leukemia ◽  
Lymphoblastic Leukemia ◽  
Leukemic Cell ◽  
Leukemic Cells ◽  
B Cell Differentiation ◽  
Cell Acute Lymphoblastic Leukemia

Abstract The BCR-ABL oncogene induces human Philadelphia-positive (Ph+) B-cell acute lymphoblastic leukemia (B-ALL) and chronic myeloid leukemia (CML) that advances to acute phase of CML called blast crisis. In this acute phase, CML patients can develop either B-ALL or acute myeloid leukemia. In B-ALL, differentiation of leukemic cells are blocked at pro-/pre-B stage, and the underlying mechanism is unknown. We hypothesize that this blockade of B-cell differentiation may be important for the development of B-ALL induced by BCR-ABL, and if so, promotion of B-leukemic cell differentiation would create a novel therapeutic strategy for B-ALL. To test this hypothesis, we first compared the percentages of IgM+ B-leukemic cells in BALB/c and C57BL/6 (B6) mice with BCR-ABL-induced B-ALL, because we have previously found that B-ALL develops more quickly in BALB/c mice than in B6 mice (Li et al, J. Exp. Med.189:1399–1412, 1999). We expressed BCR-ABL in bone marrow (BM) using retroviral transduction and transplantation in these two different strains of inbred mice to induce B-ALL. There were significantly more peripheral blood B220+ B cells in BALB/c B-ALL mice than those in B6 mice, correlating to faster B-ALL in BALB/c mice than in B6 mice. Among these B220+ cells, IgM+ cells were much less in BALB/c mice than in B6 mice. We also compared rearrangement of the B cell antigen receptor (BCR) heavy chains (m chains) between BALB/c and B6 backgrounds using BCR-ABL-expressing pro-B cell lines isolated from the B-ALL mice. Normal m chains rearrangement was found in B6 leukemic cells, but not in BALB/c leukemic cells. These results indicate that more differentiated B-leukemic cells are associated with less aggressive disease. To further demonstrate the role of blockade of B-cell differentiation in B-ALL development, we induced B-leukemic cell differentiation by co-expression of BCR-ABL and intact immunoregulatory tyrosine activation motifs (ITAM) contained in immunoglobulin (Ig)_/Igß complexes in BM cells of B-ALL mice, comparing to expression of BCR-ABL alone. We treated these mice with imatinib (orally, 100 mg/kg, twice a day). The treated mice with B-ALL induced by co-expression of BCR-ABL and ITAM lived three-week longer than those with B-ALL induced by BCR-ABL only, with some mice in long-term remission. Prolonged survival was associated with 50% increased B220+/IgM+ B-leukemic cells in peripheral blood of the mice. Taken together, our results demonstrate that blockade of B-cell differentiation is critical for the development of B-ALL induced by BCR-ABL, and provide a rationale for combination therapy of B-ALL with imatinib and induction of leukemic cell differentiation.

scholarly journals Paired Analyses of Diagnostic and Relapse Samples of MLL rearranged Infant Acute Lymphoblastic Leukemia Reveals Potential Therapy-Resistant Genomic Alterations

Blood ◽  
2014 ◽  
Vol 124 (21) ◽  
pp. 5345-5345
Author(s):  
Arjan Buijs ◽  
Marian JPL Stevens-Kroef ◽  
Edwin Sonneveld ◽  
Lars T. van der Veken
Keyword(s):  
Cell Differentiation ◽  
B Cell ◽  
Lymphoblastic Leukemia ◽  
Snp Array ◽  
B Cell Differentiation ◽  
Childhood All ◽  
Molecular Cytogenetic ◽  
Cytogenetic Analyses ◽  
One Year ◽  
Infant Acute Lymphoblastic Leukemia

Abstract Infant acute lymphoblastic leukemia (ALL) (less than one-year-old) is a rare, aggressive disease, with unique biological and clinical features. It is associated with 11q23 MLL rearrangements (MLL-R), and a high relapse risk. In contrast, in childhood ALL (age 1-18 years) the majority survives beyond 5 years, and only 15-20% of patients relapse. The genomic landscape in the latter group has been investigated quite extensively, and is has proven to be of diagnostic and prognostic significance. Paired diagnostic and relapse samples have identified frequent microdeletions in B-cell differentiation and cell cycle regulating genes IKZF1, EBF1 and CDKN2A/B. Alterations in these genes, either at diagnosis or relapse are linked to therapy-resistance. In contrast, data on copy-number alterations in infant ALL, particularly at relapse, are very limited. Therefore, we investigated two infant ALL at diagnosis and relapse by molecular cytogenetic analyses including high-density SNP array. A six-months-old boy was diagnosed with pro B-ALL. Molecular cytogenetic analyses revealed a t(4;11) MLL-AFF1 positive karyotype. SNP array resulted in a balanced profile. After a MUD-SCT the ALL relapsed at age 1.1-years. Cytogenetics demonstrated the t(4;11) stemline, and evolution with two related sidelines, one with a dic(1;19) and another with an unbalanced t(1;18), both resulting in 1q gain. In addition, SNP array analysis revealed homozygous loss of 7p12.2 IKZF1 due to an overlapping and an intragenic exon 2-3 deletion. The second case, a 3-months-old boy with pre B-ALL, showed a complex t(11;19) MLL-MLLT1 positive karyotype. Microarray analysis resulted in a balanced profile. At age one-year the ALL relapsed after a sibling-SCT, with the complex karyotype. SNP array showed a chimeric profile with only two small heterozygous 19p13.3 deletions, one including TCF3. In childhood ALL drug resistant blasts at relapse are probably subclonal at diagnosis, or develop during therapy, with frequent microdeletions of B-cell differentiation regulating genes IKZF1 and EBF1. These alterations are found particularly in MLL-wt ALL, whereas MLL-R ALL is associated with epigenetic perturbations. Interestingly, in our two cases of infant MLL-R ALL we observe, at relapse only, microdeletions of B-cell differentiation regulating genes IKZF1 and TCF3. It is of importance to study more paired cases to further define the mutational landscape of this unique, but ill-fated subtype of ALL. Disclosures No relevant conflicts of interest to declare.

scholarly journals Chromatin reader Dido3 regulates the genetic network of B cell differentiation

2021 ◽  
Author(s):  
Fernando Gutiérrez del Burgo ◽  
Tirso Pons ◽  
Enrique Vázquez de Luis ◽  
Carlos Martínez-A ◽  
Ricardo Villares
Keyword(s):  
Transcription Factors ◽  
Cell Differentiation ◽  
B Cell ◽  
Cell Lineage ◽  
Genetic Network ◽  
B Cell Differentiation ◽  
Differentiation Markers ◽  
Hematopoietic Stem ◽  
Severe Deficiency ◽  
The Impact

ABSTRACTThe development of hematopoietic lineages is based on a complex balance of transcription factors whose expression depends on the epigenetic signatures that characterize each differentiation step. The B cell lineage arises from hematopoietic stem cells through the stepwise silencing of stemness genes and balanced expression of mutually regulated transcription factors, as well as DNA rearrangement. Here we report the impact on B cell differentiation of the lack of DIDO3, a reader of chromatin status, in the mouse hematopoietic compartment. We found reduced DNA accessibility in hematopoietic precursors, leading to severe deficiency in the generation of successive B cell differentiation stages. The expression of essential transcription factors and differentiation markers is affected, as is the somatic recombination process.One Sentence Summary: Epigenetic control of early hematopoiesis

Sign in / Sign up

Export Citation Format

Share Document