Disturbed CXCR4/CXCL12 Axis In Pediatric Precursor B-Cell Acute Lymphoblastic Leukemia

Blood ◽  
2013 ◽  
Vol 122 (21) ◽  
pp. 2643-2643 ◽  
Author(s):  
Lieke C.J. van den Berk ◽  
Arian van der Veer ◽  
Marieke E. Willemse ◽  
Myrte J.G.A. Theeuwes ◽  
Mirjam W. Luijendijk ◽  
...  
Keyword(s):  
Bone Marrow ◽  
Acute Lymphoblastic Leukemia ◽  
B Cell ◽  
Conflicts Of Interest ◽  
Lymphoblastic Leukemia ◽  
Serum Levels ◽  
Initial Diagnosis ◽  
Leukemic Cells ◽  
Cxcr4 Receptor ◽  
Cell Acute Lymphoblastic Leukemia

Abstract Malignant cells that infiltrate the bone marrow (BM) interfere with the normal cellular behavior of supporting cells, thereby creating an alternative malignant niche. This intercellular communication is mostly mediated by cytokines and their receptors. In this study, we find that expression of the CXCR4 receptor is significantly increased in pediatric precursor B-cell acute lymphoblastic leukemia (BCP-ALL) cells compared with normal mononuclear hematopoietic cells derived of the bone marrow (p=0.016). Furthermore, we show that high CXCR4 expression is correlated with an unfavorable clinical outcome in BCP-ALL (5-yr CIR ±SE: 38.4% ±6.9% in CXCR4-high versus 12.0% ±4.6% in CXCR4-low expressing patients, p<0.001). Interestingly, BM serum levels of the CXCR4 ligand (CXCL12) are 2.7-fold lower (p=0.005) in samples taken at initial diagnosis of BCP-ALL compared with the levels in samples taken of non-leukemic controls. We show that induction chemotherapy restores CXCL12 levels in the BM to normal levels. Blocking the CXCR4 receptor with Plerixafor (FDA-approved drug) showed that the lower CXCL12 serum levels at initial diagnosis could not be explained by consumption by the leukemic cells, nor did we observe an altered CXCL12-production capacity of BM-MSC at this time-point. We rather observed that a very high density of leukemic cells negatively affected CXCL12 production by the BM-MSC while stimulating the secretion levels of G-CSF. These results suggest that highly proliferative leukemic cells are able to down-regulate the production of cytokines involved in homing (CXCL12), while simultaneously up-regulating the production of cytokines involved in hematopoietic mobilization (G-CSF). This disbalance may stimulate the spreading of BCP-ALL outside the BM. The data presented here suggest that interference with the CXCR4/CXCL12 axis (for instance by using Plerixafor) may be an effective way to mobilize BCP-ALL cells; the more ALL cells become mobilized, the less ALL cells may escape from combination chemotherapy. In proof-of concept studies, this hypothesis needs to be validated to pave the way for implementation in future treatment protocols for children with ALL. Disclosures: No relevant conflicts of interest to declare.

scholarly journals Frequency of IKZF1 Deletions in a Peruvian Population with B-Cell Acute Lymphoblastic Leukemia

Blood ◽  
2020 ◽  
Vol 136 (Supplement 1) ◽  
pp. 11-11
Author(s):  
Daniel J Enriquez ◽  
Rachel J. Mitchell ◽  
Krisztina Zuborne Alapi ◽  
Elizabeth Cervantes ◽  
Karina Cancino ◽  
...  
Keyword(s):  
Bone Marrow ◽  
Acute Lymphoblastic Leukemia ◽  
B Cell ◽  
Conflicts Of Interest ◽  
Lymphoblastic Leukemia ◽  
Dominant Negative ◽  
White Blood Count ◽  
Induction Treatment ◽  
Wild Type ◽  
Cell Acute Lymphoblastic Leukemia

Frequency of IKZF1 Deletions in a Peruvian Population with B-cell Acute Lymphoblastic Leukemia Background: B-cell Acute Lymphoblastic Leukemia (B-ALL) is an aggressive disease with worse outcomes in older patients, and latino ethnicity. Additionally, Latino populations are at higher risk of developing B-ALL.IKZF1is an essential lymphoid transcription factor with deletions (ΔIKZF1)implicated in treatment failure and relapses. We aimed to evaluate the frequency ofIKZF1deletions in a cohort of Peruvian patients with newly diagnosed B-ALL. Methods: We collected diagnostic bone marrow samples from 41 consecutive patients with B-ALL diagnosed between 2015-2019 at Instituto Nacional de Enfermedades Neoplasicas (INEN; Lima, Peru). Bone marrow samples were cryopreserved prior to induction treatment. DNA was extracted using High Pure PCR Template Preparation Kit (Roche) at INEN. Samples with adequate DNA were screened forΔIKZF1by multiplex endpoint PCR covering four main deletions - dominant negative Δ4-7 or the loss of function Δ2-7, Δ4-8, and Δ2-8 IKZF1 deletions at UCL Cancer Insitute (London, UK) using the primers described by Caye et. al. We analyzed outcomes byIKZF1status. Results: Forty-one cases were enrolled during the study period. Clinical characteristics are presented in Table 1. Median age was 20 years[1-63]. Fifteen∆IKZF1cases (37%) were detected (67%BCR-ABL1 negand 33%BCR-ABL1pos).Cases withΔIKZF1were older than those with wild-typeIKZF1(median age 31 vs 13 years, p=0.002). Median presenting white blood count (WBC) was 48 x109/L [R:2-218], with a higher WBC inΔIKZF1compared to wild-type (87 vs 24 x109/L, p=0.001). The most frequent deletion was ∆4-7 (sevenBCR-ABL1 negand threeBCR-ABL1 pos) additional deletions are described in table 2. All patients received intensive 'pediatric-based' treatment, 21 with BFM-2009 and 19 with the CALGB 10403 protocol. CR rates after induction were 67% and 92% for∆IKZF1and wild-type cases, respectively. Eleven (73%) of patients with∆IKZF1subjects (73%) were MRD positive by flow cytometry after induction compared to 11 (44%) among wild-type. At a median follow-up of 2 years EFS was 38% in the∆IKZF1group and 58% in the wild type group, correspond OS was 38% and 58%, respectively. Conclusion: A high frequency of IKZF1 deletions was found in a Peruvian population with B-ALL and was associated with older age and higher presenting white blood counts. Prospective studies with larger Latino population are warranted to confirm this finding. Disclosures No relevant conflicts of interest to declare.

B-Cell Precursor Acute Lymphoblastic Leukemia Cells Create a Self-Reinforcing Niche Independent of the CXCR4/CXCL12 Axis

Blood ◽  
2015 ◽  
Vol 126 (23) ◽  
pp. 1297-1297
Author(s):  
Bob de Rooij ◽  
Roel Polak ◽  
Rob Pieters ◽  
Monique L. Den Boer
Keyword(s):  
Bone Marrow ◽  
Acute Lymphoblastic Leukemia ◽  
B Cell ◽  
Conflicts Of Interest ◽  
Ex Vivo ◽  
Lymphoblastic Leukemia ◽  
Hematopoietic Cells ◽  
Leukemic Cells ◽  
Cell Precursor ◽  
Cxcr4 Antagonist

Abstract Background Acute lymphoblastic leukemia (ALL) cells create a leukemic niche that protects malignant cells from the effects of cytostatic agents and immune cells by altering their bone marrow microenvironment. This malignant process can be counteracted by impairing the homing of leukemic cells towards the bone marrow. Hematopoietic cells express the chemokine receptor CXCR4 and migrate towards its ligand CXCL12, which is actively produced by MSCs in the bone marrow. Therefore clinical trials have been initiated using the CXCR4 antagonist AMD3100 (Plerixafor) during leukemia treatment. However, these trials, as well as priming of AML in more than 4000 patients using a CXCR4 dependent mechanism, have not resulted in improved overall survival rates. This suggests that CXCR4 inhibition is not sufficient to disrupt leukemic niches. Objectives In this study we investigated how leukemic cells regulate the chemoattractive properties of their microenvironment. Results Here we show, using an ex vivo niche model with primary MSCs, that B-cell precursor ALL (BCP-ALL) cells affect their healthy microenvironment without altering CXCL12 secretion. Using a transwell migration assay we studied the chemoattractive properties and chemokine secretion patterns of several cell types and co-cultures. We confirmed that BCP-ALL cells migrate towards a CXCL12 gradient produced by primary MSCs (11-fold more migrated cells compared to background, p < 0.001). Inhibition of CXCR4 by AMD3100 reduced migration towards MSCs by 80% (p < 0.01). BCP-ALL cells migrated even more towards co-cultures of BCP-ALL cells and primary MSCs (24-fold more migrated cells compared to background, p < 0.001). Strikingly, this ex vivo leukemic niche did not produce higher levels of CXCL12 compared to MSC mono-cultures. Moreover, the induced migration towards MSC-ALL co-cultures could not be inhibited by AMD3100 treatment, indicating that BCP-ALL cells enhance the chemoattractive properties of their microenvironment in a CXCL12-independent manner. In contrast to BCP-ALL cells, the migration of CD34+ progenitor cells towards co-cultures of BCP-ALL cells and MSCs was significantly reduced (0.8-fold compared to migration towards MSCs, p < 0.05). Similar results were observed when we studied the migratory behavior of MSCs. MSCs actively migrated towards BCP-ALL cells (1.7 fold compared to background, p < 0.001), while migration of MSCs was significantly reduced towards MSC-ALL co-cultures (0.4-fold compared to migration towards BCP-ALL, p < 0.001). To find candidate factors influencing this process, we quantified the secreted levels of 64 cytokines in co-cultures of patient-derived BCP-ALL cells and MSCs. We observed leukemia-driven cytokine secretion patterns that were not influenced by the source of primary MSCs. In contrast to unaltered levels of CXCL12, we observed significant inductions of MCP-1/CCL2 and MDC/CCL22 (CCR4-ligands), IL8 and GRO-1 (CXCR1/2-ligands) and IP10/CXCL10 (CXCR3-ligands). Conclusion Our data indicate that leukemic cells alter the chemoattractive properties of their microenvironment, resulting in the secretion of multiple chemokines into the leukemic niche. This leukemic niche is highly potent in attracting BCP-ALL cells and repels the influx of healthy hematopoietic cells and MSCs using a CXCL12-independent mechanism. Furthermore, our results identify candidate factors that might be valuable future therapeutic targets. Disclosures No relevant conflicts of interest to declare.

scholarly journals Leukemia-Induced Cellular Senescence and Stemness Alterations in Mesenchymal Stem Cells Are Reversible upon Withdrawal of B-Cell Acute Lymphoblastic Leukemia Cells

2021 ◽  
Vol 22 (15) ◽  
pp. 8166
Author(s):  
Natalia-Del Pilar Vanegas ◽  
Paola Fernanda Ruiz-Aparicio ◽  
Gloria Inés Uribe ◽  
Adriana Linares-Ballesteros ◽  
Jean-Paul Vernot
Keyword(s):  
Cell Cycle ◽  
Stem Cells ◽  
Bone Marrow ◽  
Mesenchymal Stem Cells ◽  
Acute Lymphoblastic Leukemia ◽  
B Cell ◽  
Lymphoblastic Leukemia ◽  
Leukemic Cells ◽  
Hematopoietic Stem ◽  
Cell Acute Lymphoblastic Leukemia

Leukemic cell growth in the bone marrow (BM) induces a very stressful condition. Mesenchymal stem cells (MSC), a key component of this BM niche, are affected in several ways with unfavorable consequences on hematopoietic stem cells favoring leukemic cells. These alterations in MSC during B-cell acute lymphoblastic leukemia (B-ALL) have not been fully studied. In this work, we have compared the modifications that occur in an in vitro leukemic niche (LN) with those observed in MSC isolated from B-ALL patients. MSC in this LN niche showed features of a senescence process, i.e., altered morphology, increased senescence-associated β-Galactosidase (SA-βGAL) activity, and upregulation of p53 and p21 (without p16 expression), cell-cycle arrest, reduced clonogenicity, and some moderated changes in stemness properties. Importantly, almost all of these features were found in MSC isolated from B-ALL patients. These alterations rendered B-ALL cells susceptible to the chemotherapeutic agent dexamethasone. The senescent process seems to be transient since when leukemic cells are removed, normal MSC morphology is re-established, SA-βGAL expression is diminished, and MSC are capable of re-entering cell cycle. In addition, few cells showed low γH2AX phosphorylation that was reduced to basal levels upon cultivation. The reversibility of the senescent process in MSC must impinge important biological and clinical significance depending on cell interactions in the bone marrow at different stages of disease progression in B-ALL.

scholarly journals Imbalance of Chemokines and Cytokines in the Bone Marrow Microenvironment of Children with B-Cell Acute Lymphoblastic Leukemia

2021 ◽  
Vol 2021 ◽  
pp. 1-9
Author(s):  
Fábio Magalhães-Gama ◽  
Marlon Wendell Athaydes Kerr ◽  
Nilberto Dias de Araújo ◽  
Hiochelson Najibe Santos Ibiapina ◽  
Juliana Costa Ferreira Neves ◽  
...  
Keyword(s):  
Bone Marrow ◽  
Acute Lymphoblastic Leukemia ◽  
B Cell ◽  
Induction Therapy ◽  
Lymphoblastic Leukemia ◽  
Bone Marrow Microenvironment ◽  
Leukemic Cells ◽  
Cell Acute Lymphoblastic Leukemia ◽  
Ifn Γ ◽  
Immune Imbalance

In the hematopoietic microenvironment, leukemic cells secrete factors that imbalanced chemokine and cytokine production. However, the network of soluble immunological molecules in the bone marrow microenvironment of acute lymphoblastic leukemia (ALL) remains underexplored. Herein, we evaluated the levels of the immunological molecules (CXCL8, CCL2, CXCL9, CCL5, CXCL10, IL-6, TNF, IFN-γ, IL-17A, IL-4, IL-10, and IL-2) in the bone marrow plasma of 47 recently diagnosed B-cell acute lymphoblastic leukemia (B-ALL) patients during induction therapy using cytometric beads arrays. The results demonstrated that B-ALL patients showed high levels of CXCL9, CXCL10, IL-6, and IL-10 at the time of diagnosis, while at the end of induction therapy, a decrease in the levels of these immunological molecules and an increase in CCL5, IFN-γ, and IL-17A levels were observed. These findings indicate that B-ALL patients have an imbalance in chemokines and cytokines in the bone marrow microenvironment that contributes to suppressing the immune response. This immune imbalance may be associated with the presence of leukemic cells since, at the end of the induction therapy, with the elimination and reduction to residual cells, the proinflammatory profile is reestablished, characterized by an increase in the cytokines of the Th1 and Th17 profiles.

scholarly journals Toward Therapeutic Targeting of Bone Marrow Leukemic Niche Protective Signals in B-Cell Acute Lymphoblastic Leukemia

2021 ◽  
Vol 10 ◽  
Author(s):  
Marjorie C. Delahaye ◽  
Kaoutar-Insaf Salem ◽  
Jeoffrey Pelletier ◽  
Michel Aurrand-Lions ◽  
Stéphane J. C. Mancini
Keyword(s):  
Bone Marrow ◽  
Acute Lymphoblastic Leukemia ◽  
B Cell ◽  
Lymphoblastic Leukemia ◽  
Young Patients ◽  
Chemotherapeutic Agents ◽  
Leukemic Cells ◽  
Response To Treatment ◽  
Hematopoietic Stem ◽  
Cell Acute Lymphoblastic Leukemia

B-cell acute lymphoblastic leukemia (B-ALL) represents the malignant counterpart of bone marrow (BM) differentiating B cells and occurs most frequently in children. While new combinations of chemotherapeutic agents have dramatically improved the prognosis for young patients, disease outcome remains poor after relapse or in adult patients. This is likely due to heterogeneity of B-ALL response to treatment which relies not only on intrinsic properties of leukemic cells, but also on extrinsic protective cues transmitted by the tumor cell microenvironment. Alternatively, leukemic cells have the capacity to shape their microenvironment towards their needs. Most knowledge on the role of protective niches has emerged from the identification of mesenchymal and endothelial cells controlling hematopoietic stem cell self-renewal or B cell differentiation. In this review, we discuss the current knowledge about B-ALL protective niches and the development of therapies targeting the crosstalk between leukemic cells and their microenvironment.

MicroRNA Mir-125b Causes Leukemia

Blood ◽  
2010 ◽  
Vol 116 (21) ◽  
pp. 3158-3158
Author(s):  
Marina Bousquet ◽  
Marian Harris ◽  
Beiyan Zhou ◽  
Mark D. Fleming ◽  
Harvey Lodish
Keyword(s):  
Acute Lymphoblastic Leukemia ◽  
B Cell ◽  
Conflicts Of Interest ◽  
Fusion Gene ◽  
Fetal Liver ◽  
Lymphoblastic Leukemia ◽  
Macrocytic Anemia ◽  
Leukemic Cells ◽  
Cell Acute Lymphoblastic Leukemia

Abstract Abstract 3158 MicroRNA miR-125b has been shown to be involved in different kind of leukemia. Indeed, the chromosomal translocation t(2;11)(p21;q23) found in patients with myelodysplasia and acute myeloid leukemia leads to an overexpression of miR-125b up to 90 fold. Moreover, miR-125b is also upregulated in patients with B-cell acute lymphoblastic leukemia carrying the t(11;14)(q24;q32) translocation. To decipher the presumed oncogenic mechanism of miR-125b, we used transplantation experiments in mice. All of the mice transplanted with fetal liver cells ectopically expressing miR-125b showed an increase in white blood cell count, in particular in neutrophils and monocytes, associated with a macrocytic anemia. Among these mice, half of them died of B-cell acute lymphoblastic leukemia, T-cell acute lymphoblastic leukemia, or a myeloproliferative disorder, suggesting an important role of miR-125b in myeloid and lymphoid lineages. Co-expression of miR-125b and the BCR-ABL fusion gene in transplanted cells accelerated the development of leukemia in mice, compared to control mice expressing only BCR-ABL, suggesting that miR-125b confers a proliferative advantage to the leukemic cells. Thus we showed that the overexpression of miR-125b is sufficient to induce leukemia in vivo and decrease the latency of BCR-ABL -induced leukemia. Disclosures: No relevant conflicts of interest to declare.

scholarly journals The Bone Marrow Niche in B-Cell Acute Lymphoblastic Leukemia: The Role of Microenvironment from Pre-Leukemia to Overt Leukemia

2021 ◽  
Vol 22 (9) ◽  
pp. 4426
Author(s):  
Erica Dander ◽  
Chiara Palmi ◽  
Giovanna D’Amico ◽  
Giovanni Cazzaniga
Keyword(s):  
Bone Marrow ◽  
Acute Lymphoblastic Leukemia ◽  
B Cell ◽  
Lymphoblastic Leukemia ◽  
Leukemic Cell ◽  
Leukemic Cells ◽  
Bone Marrow Niche ◽  
Disease Manifestation ◽  
Cell Acute Lymphoblastic Leukemia

Genetic lesions predisposing to pediatric B-cell acute lymphoblastic leukemia (B-ALL) arise in utero, generating a clinically silent pre-leukemic phase. We here reviewed the role of the surrounding bone marrow (BM) microenvironment in the persistence and transformation of pre-leukemic clones into fully leukemic cells. In this context, inflammation has been highlighted as a crucial microenvironmental stimulus able to promote genetic instability, leading to the disease manifestation. Moreover, we focused on the cross-talk between the bulk of leukemic cells with the surrounding microenvironment, which creates a “corrupted” BM malignant niche, unfavorable for healthy hematopoietic precursors. In detail, several cell subsets, including stromal, endothelial cells, osteoblasts and immune cells, composing the peculiar leukemic niche, can actively interact with B-ALL blasts. Through deregulated molecular pathways they are able to influence leukemia development, survival, chemoresistance, migratory and invasive properties. The concept that the pre-leukemic and leukemic cell survival and evolution are strictly dependent both on genetic lesions and on the external signals coming from the microenvironment paves the way to a new idea of dual targeting therapeutic strategy.

scholarly journals Co-culture model of B-cell acute lymphoblastic leukemia recapitulates a transcription signature of chemotherapy-refractory minimal residual disease

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Stephanie L. Rellick ◽  
Gangqing Hu ◽  
Debra Piktel ◽  
Karen H. Martin ◽  
Werner J. Geldenhuys ◽  
...  
Keyword(s):  
Bone Marrow ◽  
Acute Lymphoblastic Leukemia ◽  
B Cell ◽  
Tumor Cells ◽  
Minimal Residual Disease ◽  
Residual Disease ◽  
Lymphoblastic Leukemia ◽  
Adherent Cells ◽  
Cell Acute Lymphoblastic Leukemia ◽  
Minimal Residual

AbstractB-cell acute lymphoblastic leukemia (ALL) is characterized by accumulation of immature hematopoietic cells in the bone marrow, a well-established sanctuary site for leukemic cell survival during treatment. While standard of care treatment results in remission in most patients, a small population of patients will relapse, due to the presence of minimal residual disease (MRD) consisting of dormant, chemotherapy-resistant tumor cells. To interrogate this clinically relevant population of treatment refractory cells, we developed an in vitro cell model in which human ALL cells are grown in co-culture with human derived bone marrow stromal cells or osteoblasts. Within this co-culture, tumor cells are found in suspension, lightly attached to the top of the adherent cells, or buried under the adherent cells in a population that is phase dim (PD) by light microscopy. PD cells are dormant and chemotherapy-resistant, consistent with the population of cells that underlies MRD. In the current study, we characterized the transcriptional signature of PD cells by RNA-Seq, and these data were compared to a published expression data set derived from human MRD B-cell ALL patients. Our comparative analyses revealed that the PD cell population is markedly similar to the MRD expression patterns from the primary cells isolated from patients. We further identified genes and key signaling pathways that are common between the PD tumor cells from co-culture and patient derived MRD cells as potential therapeutic targets for future studies.

A novel PAX5-ELN fusion protein identified in B-cell acute lymphoblastic leukemia acts as a dominant negative on wild-type PAX5

Blood ◽  
2006 ◽  
Vol 109 (8) ◽  
pp. 3417-3423 ◽  
Author(s):  
Marina Bousquet ◽  
Cyril Broccardo ◽  
Cathy Quelen ◽  
Fabienne Meggetto ◽  
Emilienne Kuhlein ◽  
...  
Keyword(s):  
Acute Lymphoblastic Leukemia ◽  
B Cell ◽  
Target Genes ◽  
Lymphoblastic Leukemia ◽  
Quantitative Polymerase Chain Reaction ◽  
Dominant Negative ◽  
Leukemic Cells ◽  
Dominant Negative Effect ◽  
Wild Type ◽  
Cell Acute Lymphoblastic Leukemia

Abstract We report a novel t(7;9)(q11;p13) translocation in 2 patients with B-cell acute lymphoblastic leukemia (B-ALL). By fluorescent in situ hybridization and 3′ rapid amplification of cDNA ends, we showed that the paired box domain of PAX5 was fused with the elastin (ELN) gene. After cloning the full-length cDNA of the chimeric gene, confocal microscopy of transfected NIH3T3 cells and Burkitt lymphoma cells (DG75) demonstrated that PAX5-ELN was localized in the nucleus. Chromatin immunoprecipitation clearly indicated that PAX5-ELN retained the capability to bind CD19 and BLK promoter sequences. To analyze the functions of the chimeric protein, HeLa cells were cotransfected with a luc-CD19 construct, pcDNA3-PAX5, and with increasing amounts of pcDNA3-PAX5-ELN. Thus, in vitro, PAX5-ELN was able to block CD19 transcription. Furthermore, real-time quantitative polymerase chain reaction (RQ-PCR) experiments showed that PAX5-ELN was able to affect the transcription of endogenous PAX5 target genes. Since PAX5 is essential for B-cell differentiation, this translocation may account for the blockage of leukemic cells at the pre–B-cell stage. The mechanism involved in this process appears to be, at least in part, through a dominant-negative effect of PAX5-ELN on the wild-type PAX5 in a setting ofPAX5 haploinsufficiency.

scholarly journals High cortactin expression in B-cell acute lymphoblastic leukemia is associated with increased transendothelial migration and bone marrow relapse

Leukemia ◽  
2018 ◽  
Vol 33 (6) ◽  
pp. 1337-1348 ◽  
Author(s):  
Martha Velázquez-Avila ◽  
Juan Carlos Balandrán ◽  
Dalia Ramírez-Ramírez ◽  
Mirella Velázquez-Avila ◽  
Antonio Sandoval ◽  
...  
Keyword(s):  
Bone Marrow ◽  
Acute Lymphoblastic Leukemia ◽  
B Cell ◽  
Lymphoblastic Leukemia ◽  
Transendothelial Migration ◽  
Cell Acute Lymphoblastic Leukemia
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