CXC Chemokine Ligand 13 and CC Chemokine Ligand 19 Cooperatively Render Resistance to Apoptosis in B Cell Lineage Acute and Chronic Lymphocytic Leukemia CD23+CD5+B Cells

AbstractSignaling via the B-cell receptor (BCR) is a key driver and therapeutic target in chronic lymphocytic leukemia (CLL). BCR stimulation of CLL cells induces expression of eIF4A, an initiation factor important for translation of multiple oncoproteins, and reduces expression of PDCD4, a natural inhibitor of eIF4A, suggesting that eIF4A may be a critical nexus controlling protein expression downstream of the BCR in these cells. We, therefore, investigated the effect of eIF4A inhibitors (eIF4Ai) on BCR-induced responses. We demonstrated that eIF4Ai (silvestrol and rocaglamide A) reduced anti-IgM-induced global mRNA translation in CLL cells and also inhibited accumulation of MYC and MCL1, key drivers of proliferation and survival, respectively, without effects on upstream signaling responses (ERK1/2 and AKT phosphorylation). Analysis of normal naïve and non-switched memory B cells, likely counterparts of the two main subsets of CLL, demonstrated that basal RNA translation was higher in memory B cells, but was similarly increased and susceptible to eIF4Ai-mediated inhibition in both. We probed the fate of MYC mRNA in eIF4Ai-treated CLL cells and found that eIF4Ai caused a profound accumulation of MYC mRNA in anti-IgM treated cells. This was mediated by MYC mRNA stabilization and was not observed for MCL1 mRNA. Following drug wash-out, MYC mRNA levels declined but without substantial MYC protein accumulation, indicating that stabilized MYC mRNA remained blocked from translation. In conclusion, BCR-induced regulation of eIF4A may be a critical signal-dependent nexus for therapeutic attack in CLL and other B-cell malignancies, especially those dependent on MYC and/or MCL1.

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COMPARISON OF CHROMOSOMAL REARRANGEMENTS IN BONE MARROW CELLS AND BLAST TRANSFORMED B-CELLS IN RELAPSE OF B-CELL CHRONIC LYMPHOCYTIC LEUKEMIA/ SMALL LYMPHOCYTIC LYMPHOMA

Experimental Oncology ◽

10.31768/2312-8852.2017.39(2):141-144 ◽

2017 ◽

Vol 39 (2) ◽

pp. 141-144

Author(s):

S V Andreieva ◽

K V Korets ◽

O E Ruzhinska ◽

I M Skorokhod ◽

O G Alkhimova

Keyword(s):

Bone Marrow ◽

B Cells ◽

Chronic Lymphocytic Leukemia ◽

B Cell ◽

Chromosomal Rearrangements ◽

Lymphocytic Leukemia ◽

Banding Technique ◽

Small Lymphocytic Lymphoma ◽

Detection Frequency ◽

Cell Chronic Lymphocytic Leukemia

Aim: The genetic mechanisms of resistance to chemotherapy in B-cell chronic lymphocytic leukemia/small lymphocytic lymphoma (B-CLL/SLL) are not clear. We aimed to determine the peculiarities of abnormal karyotype formation in bone marrow (BM) cells and peripheral blood (PB) blast transformed B-cells in relapse of B-CLL/SLL. Materials and Methods: Cytogenetic GTG banding technique and molecular cytogenetic in interphase cells (i-FISH) studies of BM cells and PB blast transformed B-lymphocytes were performed in 14 patients (10 males and 4 females) with B-CLL/SLL. Results: The results of karyotyping BM and PB cells revealed the heterogeneity of cytogenetic abnormalities in combined single nosological group of B-CLL/SLL. In PB B-cells, chromosome abnormalities related to a poor prognosis group were registered 2.5 times more often than in BM cells. Additional near tetraploid clones that occurred in 57.1% cases were the peculiar feature of BM cell karyotypes. Chromosomal rearrangements characteristic of the group of adverse cytogenetic prognosis were revealed in all cases from which in 2 cases by karyotyping BM cells, in 6 cases in PB B-cells and in 8 cases by the i-FISH method in BM cells, i.e. their detection frequency was 3 times higher in PB B-cells and 4 times higher when analyzing by i-FISH in BM cells. Conclusions: Mismatch in abnormal karyotypes in BM and PB B-cells by the presence of quantitative and structural chromosomal rearrangements may be indicative of simultaneous and independent processes of abnormal clone formation in the lymph nodes and BM hematopoietic cells. Accumulation the information about previously unidentified chromosomal rearrangements in relapse of the disease may help to understand the ways of resistance formation to chemotherapy.

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Defective T cell-mediated, isotype-specific immunoglobulin regulation in B cell chronic lymphocytic leukemia

Blood ◽

10.1182/blood.v71.4.1012.bloodjournal7141012 ◽

1988 ◽

Vol 71 (4) ◽

pp. 1012-1020 ◽

Cited By ~ 1

Author(s):

JS Moore ◽

MB Prystowsky ◽

RG Hoover ◽

EC Besa ◽

PC Nowell

Keyword(s):

T Cells ◽

T Cell ◽

B Cells ◽

Chronic Lymphocytic Leukemia ◽

B Cell ◽

Cell Activity ◽

Lymphocytic Leukemia ◽

Specific Immunoglobulin ◽

Cell Chronic Lymphocytic Leukemia

The consistent occurrence of T cell abnormalities in patients with B cell chronic lymphocytic leukemia (B-CLL) suggest that the non- neoplastic host T cells may be involved in the pathogenesis of this B cell neoplasm. Because potential defects of immunoglobulin regulation are evident in B-CLL patients, we investigated one aspect of this by studying the T cell-mediated immunoglobulin isotype-specific immunoregulatory circuit in B-CLL. The existence of class-specific immunoglobulin regulatory mechanisms mediated by Fc receptor-bearing T cells (FcR + T) through soluble immunoglobulin binding factors (IgBFs) has been well established in many experimental systems. IgBFs can both suppress and enhance B cell activity in an isotype-specific manner. We investigated the apparently abnormal IgA regulation in a B-CLL patient (CLL249) whose B cells secrete primarily IgA in vitro. Enumeration of FcR + T cells showed a disproportionate increase in IgA FcR + T cells in the peripheral blood of this patient. Our studies showed that the neoplastic B cells were not intrinsically unresponsive to the suppressing component of IgABF produced from normal T cells, but rather the IgABF produced by the CLL249 host T cells was defective. CLL249 IgABF was unable to suppress IgA secretion by host or normal B cells and enhanced the in vitro proliferation of the host B cells. Size fractionation of both normal and CLL249 IgABF by gel-filtration high- performance liquid chromatography (HPLC) demonstrated differences in the ultraviolet-absorbing components of IgABF obtained from normal T cells v that from our patient with defective IgA regulation. Such T cell dysfunction may not be restricted to IgA regulation, since we have found similar expansion of isotype-specific FcR + T cells associated with expansion of the corresponding B cell clone in other patients with B-CLL. These data suggest that this T cell-mediated regulatory circuit could be significantly involved in the pathogenesis of B-CLL.

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Aberrant expression of B-lymphocyte stimulator by B chronic lymphocytic leukemia cells: a mechanism for survival

Blood ◽

10.1182/blood-2002-02-0558 ◽

2002 ◽

Vol 100 (8) ◽

pp. 2973-2979 ◽

Cited By ~ 164

Author(s):

Anne J. Novak ◽

Richard J. Bram ◽

Neil E. Kay ◽

Diane F. Jelinek

Keyword(s):

B Cells ◽

Chronic Lymphocytic Leukemia ◽

B Cell ◽

B Lymphocyte ◽

Leukemic Cell ◽

Lymphocytic Leukemia ◽

Leukemic Cells ◽

Aberrant Expression ◽

B Lymphocyte Stimulator

B-cell chronic lymphocytic leukemia (B-CLL) is defined by the accumulation of CD5+ B cells in the periphery and bone marrow. This disease is not characterized by highly proliferative cells but rather by the presence of leukemic cells with significant resistance to apoptosis and, therefore, prolonged survival. B-lymphocyte stimulator (BLyS) is a newly identified tumor necrosis factor (TNF) family member shown to be critical for maintenance of normal B-cell development and homeostasis and it shares significant homology with another TNF superfamily member, APRIL. The striking effects of BLyS on normal B-cell maintenance and survival raises the possibility that it may be involved in pathogenesis and maintenance of hematologic malignancies, including B-CLL. In this study, we investigated the status of APRIL and BLyS expression, as well as their receptors, in this disease. All B-CLL patient cells studied expressed one or more of 3 known receptors for BLyS; however, the pattern of expression was variable. In addition, we demonstrate for the first time that B-CLL cells from a subset of patients aberrantly express BLyS and APRIL mRNA, whereas these molecules were not detectable in normal B cells. Furthermore, we provide in vitro evidence that BLyS protects B-CLL cells from apoptosis and enhances cell survival. Because these molecules are key regulators of B-cell homeostasis and tumor progression, leukemic cell autocrine expression of BLyS and APRIL may be playing an important role in the pathogenesis of this disease.

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Aberrant B cell receptor signaling from B29 (Igbeta , CD79b) gene mutations of chronic lymphocytic leukemia B cells

Proceedings of the National Academy of Sciences ◽

10.1073/pnas.090087097 ◽

2000 ◽

Vol 97 (10) ◽

pp. 5504-5509 ◽

Cited By ~ 24

Author(s):

M. S. Gordon ◽

R. M. Kato ◽

F. Lansigan ◽

A. A. Thompson ◽

R. Wall ◽

...

Keyword(s):

B Cells ◽

Chronic Lymphocytic Leukemia ◽

B Cell ◽

Gene Mutations ◽

Cell Receptor ◽

B Cell Receptor ◽

Lymphocytic Leukemia ◽

Receptor Signaling ◽

B Cell Receptor Signaling ◽

Cell Receptor Signaling

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Overexpression of the CXCR5 chemokine receptor, and its ligand, CXCL13 in B-cell chronic lymphocytic leukemia

Blood ◽

10.1182/blood-2007-05-089409 ◽

2007 ◽

Vol 110 (9) ◽

pp. 3316-3325 ◽

Cited By ~ 130

Author(s):

Andrea Bürkle ◽

Matthias Niedermeier ◽

Annette Schmitt-Gräff ◽

William G. Wierda ◽

Michael J. Keating ◽

...

Keyword(s):

B Cells ◽

Chronic Lymphocytic Leukemia ◽

B Cell ◽

Actin Polymerization ◽

Serum Levels ◽

Lymphocytic Leukemia ◽

Lymphoid Tissues ◽

Accessory Cells ◽

Mitogen Activated Protein ◽

B1 Cells

Abstract CXCL13 is a homeostatic chemokine for lymphocyte homing and positioning within follicles of secondary lymphoid tissues, acting through its cognate receptor, CXCR5. Moreover, the CXCR5-CXCL13 axis plays a unique role in trafficking and homing of B1 cells. Here, we report that chronic lymphocytic leukemia (CLL) B cells express high levels of functional CXCR5. CXCR5 expression levels were similar on CLL B cells and normal CD5+ B cells, and higher compared with normal CD5− B cells, follicular B-helper T cells (TFH cells), or neoplastic B cells from other B-cell neoplasias. Stimulation of CLL cells with CXCL13 induces actin polymerization, CXCR5 endocytosis, chemotaxis, and prolonged activation of p44/42 mitogen-activated protein kinases. Anti-CXCR5 antibodies, pertussis toxin, and wortmannin inhibited chemotaxis to CXCL13, demonstrating the importance of Gi proteins and PI3 kinases for CXCR5 signaling. Moreover, CLL patients had significantly higher CXCL13 serum levels than volunteers, and CXCL13 levels correlated with β2 microglobulin. We detected CXCL13 mRNA expression by nurselike cells, and high levels of CXCL13 protein in supernatants of CLL nurselike cell cultures. By immunohistochemistry, we detected CXCL13+ expression by CD68+ macrophages in situ within CLL lymph nodes. These data suggest that CXCR5 plays a role in CLL cell positioning and cognate interactions between CLL and CXCL13-secreting CD68+ accessory cells in lymphoid tissues.

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Chronic Lymphocytic Leukemia B Cells Are Resistant to the Apoptotic Effects of Transforming Growth Factor-β

Blood ◽

10.1182/blood.v89.3.941 ◽

1997 ◽

Vol 89 (3) ◽

pp. 941-947 ◽

Cited By ~ 64

Author(s):

Raymond S. Douglas ◽

Renold J. Capocasale ◽

Roberta J. Lamb ◽

Peter C. Nowell ◽

Jonni S. Moore

Keyword(s):

B Cells ◽

Growth Factor ◽

Chronic Lymphocytic Leukemia ◽

B Cell ◽

Transforming Growth Factor ◽

Transforming Growth Factor Β ◽

Lymphocytic Leukemia ◽

Western World ◽

Spontaneous Apoptosis

Abstract Chronic lymphocytic leukemia (CLL) is the most common leukemia of the western world and is characterized by a slowly progressing accumulation of clonal CD5+ B cells. Our laboratory has investigated the role of transforming growth factor-β (TGF-β) and interleukin-4 (IL-4) in the pathogenesis of B-cell expansion in CLL. In vitro addition of TGF-β did not increase spontaneous apoptosis of B cells from most CLL patients, as determined using the TUNEL method, compared with a twofold increase observed in cultures of normal B cells. There was similar expression of TGF-β type II receptors on both CLL B cells and normal B cells. In contrast to apoptosis, CLL B-cell proliferation was variably inhibited with addition of TGF-β. In vitro addition of IL-4, previously reported to promote CLL B-cell survival, dramatically reduced spontaneous apoptosis of CLL B cells compared with normal B cells. CLL B-cell expression of IL-4 receptors was increased compared to normal B cells. Thus, our results show aberrant apoptotic responses of CLL B cells to TGF-β and IL-4, perhaps contributing to the relative expansion of the neoplastic clone.

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Lymphocyte aggregation in response to adrenergic stimulation

Blood ◽

10.1182/blood.v71.5.1470.1470 ◽

1988 ◽

Vol 71 (5) ◽

pp. 1470-1474 ◽

Cited By ~ 5

Author(s):

DE Hammerschmidt ◽

C Jeanneret ◽

M Husak ◽

M Lobell ◽

HS Jacob

Keyword(s):

T Cells ◽

B Cells ◽

Chronic Lymphocytic Leukemia ◽

B Cell ◽

Lymphocytic Leukemia ◽

Binding Studies ◽

Beta Adrenergic ◽

Cell Counts ◽

Significant Difference ◽

Induced Aggregation

Abstract A nonanemic chronic lymphocytic leukemia patient with nearly 500,000 lymphocytes/microL underwent leukapheresis when she presented with CNS symptoms and retinal vascular engorgement. Respiratory distress developed during the cell separator run, which led us to ask whether the procedure could have changed the adhesive properties of her cells. C5a desarginine, N-f-Met-Leu-Phe, adenosine diphosphate, and collagen all failed to aggregate her lymphocytes in vitro, but arachidonic acid, excess free calcium, and 4 mumol/L epinephrine did aggregate the cells. Arachidonate-induced aggregation appeared to be a toxic phenomenon: the ED50 for aggregation was statistically indistinguishable from that for cytotoxicity, and aspirin only mildly blunted the response. In contrast, epinephrine-induced aggregation was not associated with lactic dehydrogenase release or the loss of trypan blue exclusion and was blunted by propranolol; radiopindolol-binding studies confirmed the presence of a beta-adrenergic receptor. There were approximately 3,000 receptors/cell, with no statistically significant difference between normal and chronic lymphocytic leukemia B cells or between B cells and T cells (separated by rosetting techniques). The Kd for the B cells' receptor, however, was less than that for T cells by a factor of ten (P less than .01). We conclude that B cells may aggregate when stimulated and that they--like T cells--have beta-adrenergic receptors. Adrenergically mediated changes in B cell adhesiveness may play a role in regulating lymphocyte traffic; in the rare patient with truly enormous B cell counts, we postulate that they may be an occasional cause of morbidity.

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