Comprehensive analysis of tumor microenvironment cytokines in Waldenstrom macroglobulinemia identifies CCL5 as a novel modulator of IL-6 activity

Abstract Although proinflammatory and chemotactic cytokines can profoundly affect the tumor microenvironment, and many of them have been shown to have therapeutic efficacy in preclinical models, the role of these molecules in Waldenström macroglobulinemia (WM) remains poorly understood. In this study, simultaneous analysis of WM patient sera and bone marrow biopsies identified a set of dysregulated cytokines including CCL5, G-CSF, and soluble IL-2 receptor, that were significantly elevated in WM patients whereas IL-8 and EGF levels were significantly lower in these patients compared with healthy controls. Interestingly, CCL5 levels positively correlated with features of disease aggressiveness such as elevated IgM levels and bone marrow involvement. Functional analysis of tumor microenvironment revealed a functional correlation between CCL5 levels and IL-6 levels, a proinflammatory cytokine with an important role in normal and malignant B-cell biology. Furthermore, CCL5 stimulated IL-6 secretion in WM stromal cells resulting in increased IgM secretion by WM malignant cells via the JAK/STAT signaling pathway. Thus, together these results define a novel signaling network in the WM tumor microenvironment controlling IgM secretion and suggest CCL5 as a potential target for the treatment of this disease.

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Lymphoplasmacytic Lymphoma and Marginal Zone Lymphoma in the Bone Marrow: Paratrabecular Involvement As an Important Distinguishing Feature

Blood ◽

10.1182/blood.v124.21.5399.5399 ◽

2014 ◽

Vol 124 (21) ◽

pp. 5399-5399

Author(s):

Assia Bassarova ◽

Gunhild Trøen ◽

Signe Spetalen ◽

Francesca Micci ◽

Anne Tierens ◽

...

Keyword(s):

Bone Marrow ◽

Marginal Zone ◽

Plasma Cells ◽

Bone Marrow Involvement ◽

Marginal Zone Lymphoma ◽

Lymphoplasmacytic Lymphoma ◽

Waldenström Macroglobulinemia ◽

Bone Marrow Trephine ◽

Waldenstrom Macroglobulinemia ◽

Myd88 L265p Mutation

Abstract Lymphoplasmacytic lymphoma and marginal zone lymphoma in the bone marrow: paratrabecular involvement as an important distinguishing feature Assia Bassarova, Gunhild Tr¿en, Signe Spetalen, Francesca Micci, Anne Tierens, Delabie Abstract Lymphoplasmacytic lymphoma (LPL) is a neoplasm of small B-lymphocytes, lymphoplasmacytoid and plasma cells involving bone marrow and sometimes lymph nodes and spleen. Lymphoplasmacytic lymphoma is often accompanied by Waldenström macroglobulinemia. Since the original description, Waldenström macroglobulinemia has become recognized as a distinct clinicopathological entity defined by serum IgM paraprotein and bone marrow involvement by lymphoplasmacytic lymphoma. Since serum IgM paraprotein in itself is not specific and can be seen in a variety of small B-cell lymphoproliferative disorders, notable chronic lymphatic leukemia and marginal zone lymphoma, as well as in rare cases of myeloma, the diagnosis of Waldenström macroglobulinemia rests largely upon the proper diagnosis of LPL in the bone marrow. The differential diagnosis between bone marrow involvement by lymphoplasmacytic lymphoma (LPL) and marginal zone lymphoma (MZL) is challenging because histology and immunophenotype of both diseases overlap. The diagnosis may be helped by demonstrating the MYD88 L265P mutation, seen in most LPL. However, the mutation is also present in MZL, although at a lower frequency. To better define the distinguishing features of LPL we studied a series of bone marrow trephine biopsies of 59 patients with Waldenström's macroglobulinemia (WM) without extramedullary involvement and compared the findings with bone marrow biopsies from 23 patients with well-characterized MZL who also had bone marrow involvement. H&E and immunoperoxidase-stained sections of bone marrow trephine biopsies as well as flow cytometry and classical cytogenetics performed on aspirations were reviewed. The study was complemented with MYD88L265P mutation analysis on the bone marrow trephine biopsies of all patients. The features are summarized in Table 1. The most distinguishing features of LPL with respect to MZL were focal paratrabecular involvement (p<0.001), the presence of lymphoplasmacytoid cells (p<0.001), Dutcher bodies (p<0.001), increased numbers of mast cells (p<0.001) and the MYD88L265P mutation (p<0.001). Other features such as sinusoidal infiltration and immunophenotype were not distinguishing. Table 1. Summary of the pathology features of lymphoplasmacytic and marginal zone lymphoma in bone marrow trephine biopsies Lymphoplasmacytic lymphoma Marginal zone lymphoma p Infiltration pattern* Paratrabecular Nodular non-paratrabecular Paratrabecular and non-paratrabecular Intrasinusoidal Diffuse 37% (10/27) 0% (0/27) 56% (15/27) 37% (10/27) 0% (0/27) 0% (0/16) 75% (12/16) 0% (0/16) 37% (6/16) 25% (4/16) <0,001 <0,001 <0,001 1 0,015 Cytology Small lymphoid cells Plasmacytoid cells Plasma cells Dutcher nuclear inclusions Mast cells 100% (59/59) 100% (59/59) 93% (55/59) 90% (53/59) 87% (49/56) 100% (23/23) 0% (0/23) 78% (18/23) 0% (0/23) 9% (2/23) - <0,001 0,108 <0,001 <0,001 Immunophenotype of the lymphoma CD20 CD138 (plasma cells) CD5 CD23 IgK IgL IgM IgG Focal CD21+ or CD23+ follicular dendritic cell network in the stroma 100% (59/59) 88% (50/57) 21% (12/52) 29% (15/51) 81% (48/59) 19% (11/59) 97% (57/59) 3% (2/59) 20% (10/51) 100% (23/23) 80% (12/15) 0% (0/23) 13% (5/23) 26% (5/19) 10% (2/19) 64% (7/11) 0% (0/11) 48% (11/23) - - 0,014 0,580 - - - - 0,024 MYD88 L265P mutation 96% (45/47) 20% (3/15) 0,001 *the analysis was only performed on bone marrow trephine biopsies showing less than 66% lymphoma infiltration In conclusion, LPL can reliably be distinguished from MZL in the bone marrow by using a combination of pathology characteristics. In contrast to other studies, our findings stress the diagnostic importance of paratrabecular infiltration in LPL. Disclosures No relevant conflicts of interest to declare.

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Targeting IL-6 reduces IgM levels and tumor growth in Waldenström macroglobulinemia

10.1101/592642 ◽

2019 ◽

Author(s):

Weiguo Han ◽

Stephan J. Matissek ◽

David A. Jackson ◽

Brandon Sklavanitis ◽

Sherine F. Elsawa

Keyword(s):

Tumor Growth ◽

Stromal Cells ◽

Tumor Volume ◽

Tumor Burden ◽

Tumor Growth Rate ◽

Waldenström Macroglobulinemia ◽

Waldenstrom Macroglobulinemia ◽

Disease Biology ◽

B Cell Malignancy

AbstractThe tumor microenvironment (TME) plays an important role in cancer and plays a role in resistance to therapy. In Waldenström macroglobulinemia (WM), a B-cell malignancy characterized by the overproduction of a monoclonal IgM protein, the TME plays an important role in WM biology by secreting cytokines that promote malignant phenotype. In previous work, we have shown that TME-IL-6 promotes WM cell growth and IgM secretion in WM. Tocilizumab/Actemra is an anti-IL-6R antibody, which can competitively block IL-6 binding to the IL-6R. We investigated the efficacy of Tocilizumab in a preclinical mouse model of WM that considers the role of the TME in disease biology. Hairless SCID mice were subcutaneously implanted with BCWM.1 or RPCI-WM1 and bone marrow stromal cells. Groups of mice were treated with Tocilizumab or control antibody three times/week for 5 weeks and the effect on tumor burden and disease biology were evaluated. Although Tocilizumab had no effect on mice survival, there was a reduction in tumor growth rate in mice injected with RPCI-WM1 cells treated with Tocilizumab (p=0.0394). In mice injected with BCWM.1 + stromal cells, there was a significant reduction in human IgM secretion in mice sera with Tocilizumab treatment (p=0.0099). There was no significant change in mice weight suggesting Tocilizumab induced no toxicities to the mice. Taken together, our data suggests that administration of Tocilizumab to tumor bearing mice, results in a significant reduction in tumor volume and IgM secretion. Therefore, the evaluation of the role of Tocilizumab in WM patients may provide therapeutic efficacy by reducing IgM production and slowing the rate of tumor growth.

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Lymphoplasmacytic Lymphoma and Waldenström Macroglobulinemia

Archives of Pathology & Laboratory Medicine ◽

10.5858/arpa.2012-0034-rs ◽

2013 ◽

Vol 137 (4) ◽

pp. 580-585 ◽

Cited By ~ 30

Author(s):

Nadia Naderi ◽

David T. Yang

Keyword(s):

Bone Marrow ◽

B Cell ◽

Bone Marrow Involvement ◽

Accurate Diagnosis ◽

Immunoglobulin M ◽

Low Grade ◽

Lymphoplasmacytic Lymphoma ◽

Waldenström Macroglobulinemia ◽

Waldenstrom Macroglobulinemia ◽

Definition Of

Lymphoplasmacytic lymphoma (LPL) is a low-grade, B-cell neoplasm composed of small lymphocytes, plasmacytoid lymphocytes, and plasma cells that typically involve the bone marrow, and it is associated with an immunoglobulin M (IgM) gammopathy. The definition of Waldenström macroglobulinemia (WM) and its relationship to LPL has been confusing in the past. In addition, the diagnosis of LPL itself can be challenging because LPL lacks disease-specific morphologic, immunophenotypic, and genetic features to differentiate it from other mature B-cell neoplasms. Accurate diagnosis of LPL/WM rests on recognition of the differential diagnostic features between LPL and other diagnostic possibilities and the use of the recently refined definition of WM and its relationship with LPL: The presence of an IgM monoclonal gammopathy of any level in the setting of bone marrow involvement by LPL. This review summarizes the clinical, laboratory, and histologic features of LPL/WM, with particular emphasis on unique aspects of LPL/WM that may aid in accurate diagnosis.

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SDF-1/CXCR4 and VLA-4 interaction regulates homing in Waldenstrom macroglobulinemia

Blood ◽

10.1182/blood-2007-12-129395 ◽

2008 ◽

Vol 112 (1) ◽

pp. 150-158 ◽

Cited By ~ 88

Author(s):

Hai T. Ngo ◽

Xavier Leleu ◽

Jack Lee ◽

Xiaoying Jia ◽

Molly Melhem ◽

...

Keyword(s):

Bone Marrow ◽

Stromal Cells ◽

Significant Inhibition ◽

Dynamic Shear ◽

Flow Conditions ◽

Waldenström Macroglobulinemia ◽

Downstream Signaling ◽

Waldenstrom Macroglobulinemia ◽

Increased Sensitivity ◽

Endothelial Migration

Abstract Waldenstrom macroglobulinemia (WM) is characterized by widespread involvement of the bone marrow at the time of diagnosis, implying continuous homing of WM cells into the marrow. The mechanisms by which trafficking of the malignant cells into the bone marrow has not been previously elucidated. In this study, we show that WM cells express high levels of chemokine and adhesion receptors, including CXCR4 and VLA-4. We showed that CXCR4 was essential for the migration and trans-endothelial migration of WM cells under static and dynamic shear flow conditions, with significant inhibition of migration using CXCR4 knockdown or the CXCR4 inhibitor AMD3100. Similarly, CXCR4 or VLA-4 inhibition led to significant inhibition of adhesion to fibronectin, stromal cells, and endothelial cells. Decreased adhesion of WM cells to stromal cells by AMD3100 led to increased sensitivity of these cells to cytotoxicity by bortezomib. To further investigate the mechanisms of CXCR4-dependent adhesion, we showed that CXCR4 and VLA-4 directly interact in response to SDF-1, we further investigated downstream signaling pathways regulating migration and adhesion in WM. Together, these studies demonstrate that the CXCR4/SDF-1 axis interacts with VLA-4 in regulating migration and adhesion of WM cells in the bone marrow microenvironment.

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Management of Waldenström macroglobulinemia in 2020

Hematology ◽

10.1182/hematology.2020000121 ◽

2020 ◽

Vol 2020 (1) ◽

pp. 372-379

Author(s):

Jorge J. Castillo ◽

Steven P. Treon

Keyword(s):

Bone Marrow ◽

Clinical Presentation ◽

Alkylating Agents ◽

Treatment Options ◽

Bone Marrow Involvement ◽

Serum Levels ◽

Immunoglobulin M ◽

Waldenström Macroglobulinemia ◽

Waldenstrom Macroglobulinemia ◽

Btk Inhibitors

Abstract The management of Waldenström macroglobulinemia (WM) has evolved tremendously with recent genomic discoveries that correlate with clinical presentation and could help to tailor treatment approaches. The current diagnosis of WM requires clinicopathological criteria, including bone marrow involvement by lymphoplasmacytic lymphoma cells, a serum immunoglobulin M (IgM) monoclonal paraprotein, and presence of the MYD88 L265P mutation. Once the diagnosis is established, the relationship between the patient’s symptoms and WM should be carefully investigated, because therapy should be reserved for symptomatic patients. Bone marrow involvement and serum levels of IgM, albumin, and β2-microglobulin can be used to estimate the time until treatment initiation. The treatment of WM patients should be highly personalized, and the patient’s clinical presentation, comorbidities, genomic profile, and preferences, as well as toxicity of the treatment regimens, should be taken into account. Alkylating agents (bendamustine, cyclophosphamide), proteasome inhibitors (bortezomib, carfilzomib, ixazomib), anti-CD20 monoclonal antibodies (rituximab, ofatumumab), and Bruton tyrosine kinase (BTK) inhibitors (ibrutinib, acalabrutinib, zanubrutinib) are safe and highly effective treatment options in patients with WM. Because novel covalent and noncovalent BTK inhibitors (tirabrutinib, vecabrutinib, LOXO-305, ARQ-531), BCL2 antagonists (venetoclax), and CXCR4-targeting agents (ulocuplumab, mavorixafor) are undergoing clinical development in WM, the future of WM therapy certainly appears bright and hopeful.

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GLI2 Transcription Factor Modulates CD40 Ligand Expression In Bone Marrow Stromal Cells

Blood ◽

10.1182/blood.v122.21.4271.4271 ◽

2013 ◽

Vol 122 (21) ◽

pp. 4271-4271

Author(s):

Matthew S. Neil ◽

Joel R. Dennison ◽

Martin E. Fernandez-Zapico ◽

Sherine F. Elsawa

Keyword(s):

Gene Expression ◽

Bone Marrow ◽

Tumor Microenvironment ◽

Stromal Cells ◽

Cell Biology ◽

Bone Marrow Stromal Cells ◽

Cd40 Ligand ◽

Malignant Cell ◽

Marrow Stromal Cells ◽

Rt Pcr

Abstract The interaction between tumor cells and their surrounding microenvironment is essential for the growth and persistence of cancer cells within the host. Cytokines play a key role in mediating this crosstalk between malignant cells and the tumor microenvironment. Although this interaction is clearly established, many of the molecular mechanisms mediating these signaling events remain elusive. In previous work, we have shown that the cytokine CCL5 can regulate the expression and activity of the transcription factor GLI2 in stromal cells. GLI2 is an effector of hedgehog (HH) signaling; however, our studies reveal a role for GLI2 independent of HH. GLI2, in turn, increases the expression and secretion of IL-6 in the tumor microenvironment, highlighting a novel role for GLI2 in directly modulating cytokine genes. We therefore screened for additional cytokines regulated by this axis in HS-5 bone marrow stromal cells using expression arrays. We found that GLI2 can modulate the expression of several cytokines including CD40 ligand (CD40L), CCL2, CCL7 and CXCL11. CD40L is an immunomodulatory and proinflammatory molecule that has been shown to play a role in multiple hematologic malignancies including chronic lymphocytic leukemia (CLL), Waldenström macroglobulinemia (WM) and acute myeloid leukemia (AML) pathogenesis. We first characterized the regulation of CD40L, because of the importance of CD40L in malignant cell biology. Gene expression results were validated by RT-PCR in two additional bone marrow stromal cell lines Saka and L88 where overexpression of GLI2 resulted in increased CD40L expression. Furthermore, we detected increased levels of soluble CD40L (sCD40L) in L88 and Saka cells overexpressing GLI2. Conversely, knockdown of GLI2 resulted in reduced expression and secretion of this cytokine. Biochemical mapping of the domains critical for this GLI2 regulatory mechanism reveals that N-terminal transcriptional domain is dispensable, as a mutant form of GLI2 lacking this domain (delta N-GLI2) increases CD40L gene expression by RT-PCR, protein expression by western blot and sCD40L secretion by ELISA, beyond that of the full-length GLI2 levels. Bioinformatics analysis of the CD40L promoter indicates the presence of 3 candidate binding sites for GLI proteins, suggesting the modulation of CD40L by GLI2 is mediated by direct interaction with its promoter. Ongoing experiments are aimed at determining the mechanism by which GLI2 regulates CD40L expression (either by direct binding to the CD40L promoter or through another indirect pathway). Together, our data identify a novel mechanism controlling CD40L in stromal cells in the bone marrow microenvironment. Because of the importance of CD40L in malignant cell biology, understanding the mechanism of its regulation is of great importance for the development of therapies aimed at targeting the malignant bone marrow tumor microenvironment. Disclosures: No relevant conflicts of interest to declare.

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PD-1 Is Expressed on B-Cells in Waldenstrom Macroglobulinemia and Promotes Malignant Cell Viability and Proliferation

Blood ◽

10.1182/blood.v124.21.3015.3015 ◽

2014 ◽

Vol 124 (21) ◽

pp. 3015-3015

Author(s):

Stephen M. Ansell

Keyword(s):

Bone Marrow ◽

Flow Cytometry ◽

B Cells ◽

Cell Growth ◽

Cell Lines ◽

Stromal Cells ◽

Malignant Cell ◽

Growth And Survival ◽

Waldenström Macroglobulinemia ◽

Waldenstrom Macroglobulinemia

The tumor microenvironment plays an important role in regulating malignant cell growth and mechanisms to enhance anti-tumor immune function have been shown to improve patient outcome. Interactions between programmed death 1 (PD-1) and its ligands (PD-L1 and PD-L2) have been shown to be an important checkpoint in immune regulation. While it is well known that PD-1 is expressed on normal T cells and signaling through PD-1 inhibits T cell function, PD-1 is also expressed on a subset of B-cells but little is known about PD-1 signaling in B-cells. The goal of this study was to determine if the PD-1 is expressed on malignant B cells in Waldenstrom macroglobulinemia (WM) and whether this pathway plays a role in the survival and growth of malignant B cells in this B cell lymphoma. Using flow cytometry, we found that the cell lines MWCL-1, BCWM.1 and RPCI, all derived from patients with Waldenstrom macroglobulinemia, expressed PD-1 to varying degrees on their cell surface. PD-1 expression in the cell lines was further confirmed by RT PCR analysis. Using flow cytometry and immunohistochemistry to examine bone marrow specimens from WM patients, we further confirmed PD-1 expression on CD19+ CD138+ malignant B-cells. Furthermore, intense staining for the ligands PD-L1 and PD-L2 was found by in bone marrows of WM patients when compared to normal bone marrow specimens. When WM cell lines are co-cultured with stromal cells engineered to express PD-L1 or PD-L2, there was a consistent increase in cell viability compared to controls. When malignant B cells from WM patients were co-cultured with stromal cells expressing the ligands, viability was unchanged but there was an increase in cell proliferation, most noticeably when cocultured with cells expressing PD-L2. To determine potential mechanisms that account for upregulation of PD-1 on malignant B-cells, we tested whether cytokines that promote WM cell growth and survival, including IL-6, IL-21 and BAFF, increased PD-1 expression. We found that WM cell lines and patient derived CD19+CD138+WM B-cells (n=4) treated with IL-21 demonstrated an increase in PD-1 expression compared to untreated controls. We conclude that PD-1 is expressed on malignant B-cells in WM and that signaling through PD-1 may promote WM cell growth and survival. Blocking PD-1/PD ligand interactions may therefore be a potential therapeutic strategy in patients with Waldenstrom macroglobulinemia. Disclosures No relevant conflicts of interest to declare.

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