Myeloma Cell Survival and Importance of Crosstalk Between Notch1-Jagged2 and CD28-B7 Pathways In Dendritic Cells

Blood ◽  
2010 ◽  
Vol 116 (21) ◽  
pp. 1741-1741
Author(s):  
Chandana Koorella ◽  
Jayakumar Nair ◽  
Louise Carlson ◽  
Megan Murray ◽  
Cheryl H Rozanski ◽  
...  
Keyword(s):  
Bone Marrow ◽  
Dendritic Cells ◽  
Notch Signaling ◽  
Cell Biology ◽  
Conflicts Of Interest ◽  
Myeloma Cell ◽  
Negative Regulator ◽  
Soluble Form ◽  
Myeloma Cells ◽  
Notch1 Signaling

Abstract Abstract 1741 Multiple myeloma is a neoplasm of bone marrow resident plasma cells characterized by critical interactions between myeloma cells and bone marrow stromal cells. This interaction leads to production of IL-6, an important factor in myeloma cell biology. However, the molecular and cellular components involved in myeloma induced IL-6 production remain largely uncharacterized. While at the cellular level, dendritic cells (DC)-expressing CD80/CD86 (collectively called B7, ligands with short cytoplasmic tails and signaling partners of CD28 expressed on myeloma cells) - in the bone marrow microenvironment have been implicated as being an important component, at the molecular level the CD28-B7 and Notch1-Jagged2 pathways were separately implicated by us (in DC) and others in myeloma induced IL-6 production. Although Notch signaling leading to IL-6 production in DC is well understood, the mechanism of “backsignaling” via B7 is largely uncharacterized. To better understand downstream B7 signaling leading to IL-6 production, DC were stimulated with CD28-Ig (a soluble form of CD28 which mimicks myeloma cell-bound CD28) in the presence or absence of an inhibitor of Notch signaling, gamma secretase inhibitor (GSI). DC treated with CD28-Ig alone produced significantly (p< 0.001) higher levels of IL-6 when compared to DC treated with CD28-Ig and GSI. GSI specifically targeted Notch signaling as observed by decreased expression of Notch gene targets: Hes-1 (2 fold decrease) and Deltex-4 (4 fold decrease). Also, decreased IL-6 levels in presence of GSI were not due to the decrease in B7 expression on DC. To specifically implicate the importance of Notch1 and Jagged2, we blocked Notch1 signaling using blocking antibodies and observed a similar decrease in IL-6 production upon blocking Notch1 signaling. Our results suggest that CD28 mediated IL-6 production is dependent on Notch1 signaling and crosstalk between the Notch1-Jagged2 and CD28-B7 pathways leads to IL-6 production by DC. The model of crosstalk between CD28-B7 and Notch1-Jagged2 pathways was also observed in murine bone marrow derived dendritic cells (BMDC), where a significant (p<0.001) down regulation of IL-6 was observed upon blocking Notch signaling. One possible mechanism of crosstalk involves direct effect of B7 crosslinking by CD28-Ig on Notch expression/signaling leading to increase in IL-6 production. We tested for this possibility in DC and found no significant change in Notch expression/signaling. We thus hypothesized that the mechanism of crosstalk involves molecules downstream to Notch and/or B7. Notch signaling has been reported to be involved in the regulation of PTEN (a negative regulator of the PI3K/Akt pathway). Previous studies have also shown the importance of FoxO3a-a transcription factor tightly regulated by Akt- in regulating IL-6 production in BMDC upon B7 crosslinking. We therefore tested the possible involvement of PTEN (molecule downstream of Notch signaling), Akt and FoxO3a (molecules downstream of B7) in crosstalk between the two pathways aforementioned by testing the effect of GSI on their regulation at the protein level. We observed an approximate 2 fold decrease in phospho-PTEN/PTEN ratio in DC treated with GSI and remained so even after B7 crosslinking at an early time point (15 min. post CD28-Ig treatment.) Further, phospho-Akt/Akt ratio decreased by 1.6 fold in DC treated with both GSI and CD28-Ig compared to CD28-Ig alone at 30 min. We therefore hypothesize a model of crosstalk involving Notch mediated regulation of PTEN leading to IL-6 production via regulation of Akt and possibly FoxO3a upon B7 crosslinking. Interestingly enough “backsignaling” via B7 in myeloma-induced IL-6 production seems to involve molecules well characterized in CD28 signaling of T-cells. Targeting IL-6 induced by crosstalk between these two pathways prompts not only clinical evaluation to improve MM patient outcome but also extends to advancing knowledge in T-cell and normal plasma cell biology as well. Disclosures: No relevant conflicts of interest to declare.

scholarly journals Chondroitin Synthase 1 Is a Key Molecule in Myeloma Cell-Osteoclast Interactions

2004 ◽  
Vol 280 (16) ◽  
pp. 15666-15672 ◽  
Author(s):  
Larry Yin
Keyword(s):  
Bone Marrow ◽  
Notch Signaling ◽  
Conditioned Medium ◽  
Molecular Mechanisms ◽  
Plasma Cells ◽  
Ex Vivo ◽  
Bone Destruction ◽  
Fold Increase ◽  
Myeloma Cell ◽  
Myeloma Cells

There is a symbiotic relationship between continued growth and proliferation of myeloma cells and the bone destructive process. It has been shown in animal models that blocking bone destruction can result in decreased myeloma tumor burden. Osteoclasts are bone destroying cells found in the bone marrow, and their significance in myeloma is supported by recent findings that osteoclasts alone can support sustained survival and proliferation of purified primary myeloma cells inex vivoco-cultures. However, molecular mechanisms associated with interactions between myeloma cells and osteoclasts remain unclear. Here, we show that when myeloma plasma cells are co-cultured with osteoclasts, chondroitin synthase 1 (CHSY1) is the most significantly altered soluble, secreted protein present in the conditioned medium. RNA interference experiments with CHSY1 small interfering RNA (siRNA) reduced the amount of CHSY1 in the co-culture conditioned medium, and this was associated with a 6.25-fold increase in apoptotic myeloma cells over control co-cultures. CHSY1 contains a Fringe domain, and Fringe is well known for its regulation of Notch signaling via its DDD motif. And interestingly, Fringe domain in CHSY1 has this DDD motif. Shortly after co-culture with osteoclasts, we found that the Notch2 receptor was activated in myeloma cells but Notch1 was not. Activation of Notch2 was down-regulated by CHSY1 siRNA treatment. Modulating Notch signaling by CHSY1 via its DDD motif provides new insight into mechanisms of the interactions between myeloma cells and their bone marrow microenvironment. Targeting this interaction could shed light on treatment of myeloma, which is currently incurable.

scholarly journals Myeloma Cells Have the Ability to Suppress Th1-Inducing Capacity but Enhance Th2-Mediated Response of Dendritic Cells By Producing Factors Other Than Soluble SLAMF7

Blood ◽  
2018 ◽  
Vol 132 (Supplement 1) ◽  
pp. 1938-1938
Author(s):  
Yoshiko Azuma ◽  
Tomoki Ito ◽  
Muneo Inaba ◽  
Kai Imai ◽  
Hideaki Yoshimura ◽  
...  
Keyword(s):  
Dendritic Cells ◽  
Cell Lines ◽  
Cell Function ◽  
Killer Cell ◽  
Myeloma Cell ◽  
Immune Defense ◽  
Th2 Cells ◽  
Soluble Form ◽  
Th2 Response ◽  
Myeloma Cells

Abstract Background: Lenalidomide (LEN), as a backbone drug for multiple myeloma (MM), has both direct tumoricidal and immunomodulatory effects in MM. LEN displays immunopotentiating activity, including augmentation of T and natural killer cell function and to induce selective reduction of regulatory T cells. Thus, the immune-based cancer treatments are currently important in MM therapy. Since myeloma cells together with immune cells are immersed in the pathogenic micro-environment, understanding the influence of micro-environment against myeloma cells and immune system may lead to the development of novel treatment strategies for MM. Series of analyses have clarified a functional plasticity of dendritic cells (DCs) to induce Th1 or Th2 response and DCs are pivotal in orchestrating both innate and acquire immune responses also in the anti-tumor immunity. Here, we focused on the effects of myeloma environment to modulate the human myeloid DCs (mDCs), which are the major regulators to induce Th1 or Th2 responses. Soluble form of SLAMF7 (sSLAMF7) is a pivotal environmental component of MM and functions as a self-ligand of myeloma cells. sSLAMF7 has been detected in the serum of patients with MM at higher levels than healthy individuals and therefore may presumably play some roles in pathophysiological condition of MM. To evaluate the functions of soluble factors/components derived from myeloma cells, we analyzed whether supernatants of myeloma cell lines could modulate mDC functions. Methods: Using cell sorting, blood human CD11+ mDCs were isolated from healthy adult volunteers. The DC functions were analyzed after culture for 24 h with supernatant of myeloma cell lines, NCI-H929 (H929) or MM.1R. This study was approved by the Institutional Review Board of Kansai Medical University.Results: We here found that both supernatants of myeloma cell lines, H929 and MM.1R did not affect CD86 expression on mDCs in response to toll-like receptor (TLR)-ligand (R848), but upregulated their CD86 expression in response to Th2-inducing cytokine, thymic stromal lymphopoietin (TSLP). Of note, the supernatants inhibited mDC-derived IL-12 production in response to R848 (p < 0.05: H929; 25-30% of cont. and MM1.R; less than 50 % of cont.), while in response to TSLP, dose-dependently enhanced the Th2-recruiting chemokine CCL17/TARC production (p < 0.05: H929; 130- 210 % of cont. and MM1.R; 120-185 % of cont.), which functions as chemoattractant for memory Th2 cells and contribute to promote humoral response. In addition, we revealed that these capacities were further enhanced by the addition of LEN at clinical in vivo plasma concentration of 1 µM. Thus, MM micro-environment could have the potential to shift DC-mediated response from Th1 to Th2. To clarify whether sSLAMF7 in the supernatant of myeloma cell lines play a role in the Th1/Th2-modulating effect, we calculated the sSLAMF7 concentration in the supernatants and analyzed an inhibitory effect of elotuzumab for the DC function induced by the supernatants. sSLAMF7 could not be detected at all in the supernatants of both myeloma cell lines, even in any concentration of cells. Furthermore, addition of 30 to 100 ug/ml (clinical trough serum concentration) elotuzumab into the culture of mDCs and the supernatants did not affect the CD86 expression and IL-12/CCL17 production. Hence, factors other than sSLAMF7 from myeloma cells can trigger DCs to suppress Th1 response and to promote Th2 response.Conclusion: Our data suggest that the MM micro-environment, while suppress the Th1-inducing capacity, rather lead to enhance Th2 response at DC phase. As sSLAMF7 is detected in the serum of patients with MM but not in the supernatants of MM cell lines in the experimental setting, there is a limitation that our data does not consider the action of sSLAMF7. However, the present result provides an important clue for understanding the biological basis for the MM micro-environment against host immune defense at onset. Disclosures Ito: Bristol-Myers Squibb: Honoraria, Research Funding; Takeda: Honoraria; Novartis Pharma: Honoraria; Pfizer: Honoraria; Mundipharma: Honoraria; Celgene: Honoraria.

scholarly journals Morphogens and growth factor signalling in the myeloma bone-lining niche

2021 ◽  
Author(s):  
Emma V. Morris ◽  
Claire M. Edwards
Keyword(s):  
Bone Marrow ◽  
Cell Biology ◽  
Plasma Cells ◽  
Cell Types ◽  
Myeloma Cell ◽  
Bone Cell ◽  
Signalling Pathways ◽  
Perivascular Niche ◽  
Myeloma Cells ◽  
Endosteal Niche

AbstractMultiple myeloma is a malignancy caused by the clonal expansion of abnormal plasma cells. Myeloma cells have proven to be incredibly successful at manipulating their microenvironment to promote growth and to evade modern therapies. They have evolved to utilise the integral signalling pathways of the bone and bone marrow to drive disease progression. The bone marrow is often described in the context of a single structure that fills the bone cavity and supports normal haematopoiesis. However, within that structure exists two anatomically different niches, the perivascular niche and the endosteal niche. These contain different cell types functioning to support normal immune and blood cell production as well as healthy bone. These cells secrete numerous signalling molecules that can influence myeloma cell biology and behaviour. The endosteal niche is home to specific bone cell lineages and plays a pivotal role in myeloma cell establishment and survival. This review will concentrate on some of the signalling pathways that are hijacked by myeloma cells to shape a favourable environment, and the different influences myeloma cells are exposed to depending on their spatial location within the bone marrow.

scholarly journals Resistin Induces Multidrug Resistance in Myeloma By Inhibiting Cell Death and Upregulating ABC Transporter Expression

Blood ◽  
2016 ◽  
Vol 128 (22) ◽  
pp. 5656-5656
Author(s):  
Jianan Pang ◽  
Qiaofa Shi ◽  
Zhiqiang Liu ◽  
Jin He ◽  
Huan Liu ◽  
...  
Keyword(s):  
Bone Marrow ◽  
Protective Effect ◽  
Abc Transporters ◽  
Conflicts Of Interest ◽  
Myeloma Cell ◽  
Long Term Outcome ◽  
Myeloma Cells ◽  
Chemotherapy Drugs ◽  
Response To Chemotherapy ◽  
Induced Apoptosis

Abstract Chemoresistance is a major hurdle in multiple myeloma. Most patients are prone to develop resistance to a wide spectrum of anticancer agents, significantly hampers the patients' long term outcome. Many studies point to bone marrow microenvironment as an important player in myeloma chemoresistance, in which marrow stromal cells and stromal-secreted soluble factors are shown to promote myeloma cell growth and survival. Our previous study has demonstrated that marrow-derived adipocytes protect myeloma cells against chemotherapy-induced apoptosis through adipocyte-secreted adipokines, one of such is leptin. However, the level of leptin expression in myeloma patients is not significantly changed, indicating the involvement of additional adipokines in this process. Interestingly, in a clinical study, an elevation of the adipokine resistin in the serum of myeloma patients after thalidomide treatment were observed as compared with that in patients before treatment, suggesting a potential role of this adipokine in response to chemotherapy. As a 12.5-kDa hormone that is mainly secreted by adipocytes and also secreted by other cells, resistin has a function in production of inflammatory cytokines that are important for cancer development. We thus hypothesized that resistin protects myeloma cells against chemotherapy. In our experiments, human myeloma cell lines and primary myeloma cells isolated from patient bone marrow aspirates were cultured in medium with addition of the recombinant human resistin and chemotherapy drugs melphalan or bortezomib for 24 hours. Cells without resistin served as a control. After cultures, an annexin-V binding assay for assessing apoptosis, western blot analysis for assessing cleavage of caspases and phosphorylation of signaling kinases, and the eFluxx-ID Gold uptake assay for examining ABC transporters activity were performed. In the animal study, myeloma-bearing SCID mice were treated with or without resistin and/or melphalan. Our results showed that resistin treatment reduced melphalan- or bortezomib-induced apoptosis both in vitro and in vivo. This protective effect has been further confirmed by the reduced cleavage of caspase-9, caspase-3, and poly (ADP-ribose) polymerase in myeloma cells. Mechanistic studies showed that culturing myeloma cells with resistin upregulated expression of the anti-apoptotic proteins Bcl-2 and Bcl-xL and downregulated expression of the pro-apoptotic protein Bax via the NF-kB and the PI3K/Akt signaling pathways. Addition of resistin also reduced the intracellular accumulation of eFluxx-ID gold fluorescence in myeloma cells ARP-1 and MM.1S, when compared to that in cells without resistin. In addition, resistin significantly increased the mRNA and protein expression of ATP-binding cassette (ABC) transporters in myeloma cells by downregulating the expression of DNA methyltransferase 1 and 3a, and CpG methylation in the promoters of ABC transporters. Thus, our study demonstrates that resistin is a novel factor contributing to myeloma chemoresistance, and also implicates that disruption of its protective effect can be a potential strategy to improve current chemotherapy in patients and prolong survival. Disclosures No relevant conflicts of interest to declare.

scholarly journals Proteomic and Biological Analysis of Myeloma Cell Derived Extracellular Vesicles

Blood ◽  
2018 ◽  
Vol 132 (Supplement 1) ◽  
pp. 5605-5605
Author(s):  
Dominique B Hoelzinger ◽  
Sophia J Quinton ◽  
Denise K Walters ◽  
Renee C Tschumper ◽  
Diane F Jelinek
Keyword(s):  
Bone Marrow ◽  
Cell Proliferation ◽  
Cell Lines ◽  
Proteomic Analysis ◽  
Cell Biology ◽  
Conflicts Of Interest ◽  
Myeloma Cell ◽  
Cellular Adhesion ◽  
Biologically Relevant ◽  
Common Genetic Variants

Abstract Intercellular communication between multiple myeloma (MM) cells and the normal bone marrow stroma leads to a modification of the bone marrow microenvironment, which favors tumor progression. New developments in extracellular vesicle (EV) research suggest that this diverse population of vesicles, released by cancer cells including MM cells, express transmembrane proteins and carry cargo that can modify recipient cells in myriad ways. In particular, tumor-derived EVs have been shown to create permissive microenvironments that lead to metastatic colonization by circulating tumor cells. As we have previously shown that MM EVs can enhance proliferation of recipient MM cells, we hypothesize that MM EVs can potentially play a much larger role in MM development and progression. In order to understand the scope of potential EV roles in MM, we executed a comprehensive proteomic analysis of the cargo of MM EVs. We isolated EVs from patient derived MM cell lines that represent the most common genetic variants of this tumor, and used in vitro generated plasma cells (IVPCs) as a reference population. In a first pass analysis, we selected proteins that were expressed ≥3 fold higher in MM EVs than in IVPC EVs, and this analysis identified 306 proteins. Of interest, included in the 306 differentially proteins were several involved in the regulation of cell adhesion such as members of the a disintegrin and metalloprotease domain (ADAM8, 9, 10, 13, 15 and 22) family, which are also associated with inhibition of cell proliferation. Moreover, CEACAM1, PTPRK, and CDH2, which are also linked to cellular adhesion, were also expressed at a higher level in MM EVs. Various proteins linked to myeloma cell biology were likewise found to be over-represented in MM EVs, and these include BCMA, ITGAV, ITGB5, IL6ST (gp130), CD276 (B7-H3), and CD28. As we are most interested in biologically relevant and actionable proteins present uniquely in MM derived EVs, we filtered from our data proteins that were also present in EVs from IVPCs. We further filtered out proteins known to be present in EVs from normal cells. This filtering strategy reduced the number of interesting candidates to 8, which included CD28, MET, TRKC, and ADAM15. Thus far, we have confirmed the presence of these 4 proteins in a panel of MM EVs, and we are currently in the process of validating additional candidate cargo proteins for their biological role in enhancing tumor cell proliferation and/or protection from apoptosis. In summary, EV proteomic analysis of cell lines representing MM genetic subtypes can lead to the identification of biologically relevant proteins transported systemically by EVs as well as suggest novel biomarkers that are easily detectable in plasma and may permit earlier recognition of disease progression in patients with MM. Disclosures No relevant conflicts of interest to declare.

GCS-100 Targets Apoptosis and Cell Cycle Regulation in Myeloma Cells.

Blood ◽  
2009 ◽  
Vol 114 (22) ◽  
pp. 4923-4923
Author(s):  
Matthew Streetly ◽  
Lenushka Maharaj ◽  
Simon P Joel ◽  
Finbarr E Cotter
Keyword(s):  
Cell Cycle ◽  
Cell Lines ◽  
Cell Biology ◽  
Transmembrane Potential ◽  
Conflicts Of Interest ◽  
Myeloma Cell ◽  
Clinical Activity ◽  
Apoptosis Resistance ◽  
Cell Viability Assay ◽  
Myeloma Cells

Abstract Abstract 4923 Introduction Myeloma is characterised by abnormalities of multiple cellular pathways that result in apoptosis resistance, aberrant signalling and deregulated cell cycle. GCS-100 is a modified citrus pectin that has demonstrated galectin-3 inhibitory activity. It has recently been reported to have clinical activity against CLL (Cotter et al. ASCO 2009) and has previously been observed to have pre-clinical anti-myeloma effect even in the context of bortezomib resistance (Chauhan et al. Canc Res 2005). We have elucidated the mechanisms of action of GCS-100 in the context of myeloma cell biology. Methods The effects of GCS-100 on myeloma cell proliferation, cell cycle, apoptosis induction, cell death and cell signalling were examined in representative cell lines and primary myeloma cells. Cell viability assay, flow cytometric assessment of apoptosis, DNA content, mitchochondrial transmembrane potential and immunoblotting assessment of protein expression were assessed following GCS-100 exposure. Results Exposure of RPMI8226, U266 and OPM2 myeloma cell lines to GCS-100 confirmed that it inhibits proliferation and induces apoptosis with activation of both caspase-8 and -9 pathways. GCS-100 exposure was also associated with accumulation of cells in sub-G1 and G1 phases of cell cycle and a dose and time dependent loss of mitochondrial potential. Primary myeloma cells treated with GCS-100 had reduced viability both in isolation and in a stromal cell co-culture model. Examination of key anti-apoptotic and pro-apoptotic proteins revealed that Mcl-1 and Bcl-xL levels were reduced by GCS-100 and this was accompanied by a rapid induction of pro-apoptotic Noxa. Bcl-2, Bax, Bak, Bim, Bad, Bid and Puma remained unchanged. Pan-caspase inhibition abrogated Mcl-1 but not Bcl-XL reduction and inhibited loss of mitochondrial transmembrane potential. GCS-100 treatment also upregulated the cell cycle inhibitor p21Cip1 with concurrent reduction of the procycling proteins cyclin E2, cyclin D2 and CDK6. Furthermore, there was a reduction in signal transduction in the form of reduced activated IκBα, IKK and Akt as well as prevention of upregulated IκBα and Akt following stimulation with appropriate cytokines suggesting a potential microenvironment effect. Conclusion GCS-100 is a potent modifier of myeloma cell biology in a manner suitable for novel myeloma therapy. Disclosures No relevant conflicts of interest to declare.

Multiple Myeloma Cells Adhere to Netrin-1 Via Heparin-Sulphate Moieties

Blood ◽  
2012 ◽  
Vol 120 (21) ◽  
pp. 3952-3952
Author(s):  
Jeesun Park ◽  
David R Fooksman ◽  
Amitabha Mazumder ◽  
Michael L Dustin
Keyword(s):  
Multiple Myeloma ◽  
Bone Marrow ◽  
Cell Adhesion ◽  
Conflicts Of Interest ◽  
Cell Spreading ◽  
Myeloma Cell ◽  
Axonal Guidance ◽  
Intercellular Adhesion Molecule ◽  
Myeloma Cells ◽  
Guidance Cue

Abstract Abstract 3952 A major obstacle to the treatment of Multiple Myeloma (MM) is the localization of myeloma cells to the bone marrowstroma, enabling drug resistance. The exact mechanisms of adhesion of myeloma cells to the bone marrow are not known, but adhesion molecules and chemokine signals, in particular vascular cell adhesion protein 1 (VCAM-1) and C-X-C chemokine 12 (CXCL12) which control bone marrow tropism, are thought to be the main players. Netrin-1, which acts as an axonal guidance cue, plays a role in leukocyte migration in lymph nodes and in atherosclerotic lesions, but has not been tested as a substrate for myeloma cell adhesion previously. Based on expression of the netrin-1 receptor Deleted in Colorectal Cancer (DCC) on activated human B cells, we tested the ability of myeloma cells to adhere to netrin-1, an axonal guidance cue. Using interference reflection microscopy (IRM) which employs the method of interference of light reflected from nearby surfaces to measure cell-substratum distances and cell-substratum adhesion, we assessed cell adhesion and cell spreading on substrates immobilized on glass. Here, we used this technique to assess myeloma cell adhesion and migration on various substrates and found netrin-1 to be an exceptional adhesion ligand for myeloma cells. We prepared glass substrates coated with the recombinants ligands intercellular adhesion molecule,ICAM-1(50μM), and VCAM-1(50μM), with or without chemokine ligand, CXCL12(0.1mg/mL), which have been implicated in plasma cells and myeloma cell migration, previously. We used freshly purified, fluorescently-labeled primary myeloma cells from newly diagnosed patients, prior to any treatment. Using IRM, we imaged the cell contacting the substrate in order to measure adhesion and differentiate crawling versus fluid flow movement. Based on the IRM image, we could calculate the fraction of cells in the field that were adhered to the substrate, and compared between conditions and for various patient samples. We observed that myeloma cells can adhere and migrate slowly on VCAM-1 in the presence of CXCL12, but are unable to adhere to ICAM-1 with or without chemokines. We tested myeloma cell binding to netrin-1 and saw a strong adhesion 60–90% of cells in 7 out of 9 patients samples tested. The cell spreading on netrin-1 was more than 3 times larger than on VCAM-1 with CXCL12 substrates. Expression of netrin-1 in the bone marrow has not been determined yet nor its role in MM. Heparin-like molecule, SST0001, has been tested in myeloma studies, in an attempt to interfere with heparinase activity and syndecan-1 shedding, and tumor growth. We tested pre-blocking netrin-1 substrates with heparin and observed elimination of greater than 95% of myeloma cell adhesion in all patients samples tested. Treating patients with heparin-like molecules may have additional functions, by blocking binding to netrin-1 and soluble signals that contain heparin-binding domains. Reciprocally, blocking heparin-sulfated groups with netrin-1 may block myeloma cell adhesion and can be used to targeting strategy for chemotherapeutic drugs as well. Disclosures: No relevant conflicts of interest to declare.

scholarly journals Heterogeneous expression of a novel MPC-1 antigen on myeloma cells: possible involvement of MPC-1 antigen in the adhesion of mature myeloma cells to bone marrow stromal cells

Blood ◽  
1993 ◽  
Vol 82 (12) ◽  
pp. 3721-3729 ◽  
Author(s):  
N Huang ◽  
MM Kawano ◽  
H Harada ◽  
Y Harada ◽  
A Sakai ◽  
...  
Keyword(s):  
Bone Marrow ◽  
B Cells ◽  
Cell Line ◽  
Bone Marrow Stromal Cells ◽  
Plasma Cells ◽  
Myeloma Cell ◽  
Myeloma Cell Line ◽  
Myeloma Cells ◽  
Human Myeloma Cell Line ◽  
Heterogeneous Expression

Abstract Recent immunophenotypic analysis has shown that the heterogeneous expression of the adhesion molecule VLA-5 classifies myeloma cells into VLA-5+ mature and VLA-5- immature subpopulations. To further clarify the two myeloma subpopulations, we generated a monoclonal antibody, MPC- 1, by immunizing mice with an adherent human myeloma cell line, KMS-5. The MPC-1 antibody recognized a 48-Kd surface antigen on KMS-5 but not on U-266, a nonadherent human myeloma cell line. Specificity characterization showed that MPC-1 antigen was expressed on mature myeloma cells, normal plasma cells, and mature B cells, whereas pre-B cells and germinal center B cells lacked its expression. Monocytes and a human bone marrow stromal cell line, KM102, also expressed this antigen. Two subclones of MPC-1+ VLA-5+ (KMS-5Ad) and MPC-1-VLA-5+ (KMS- 5NAd) were separated from the KMS-5 cell line. The KMS-5NAd adhered to KM102 more tightly than did the KMS-5NAd, and the U-266 (MPC-1-VLA-5-) displayed almost no adherence to the KM102. The adhesion of the KMS-5Ad was partially inhibited by the MPC-1 antibody. These results, taken together, suggest that the MPC-1 antigen serves as a differentiation marker for B-lineage cells, including plasma cells, and may function as an adhesion molecule involved in the interaction of mature myeloma cells with bone marrow stromal cells.

scholarly journals Plasma cells induce apoptosis of pre-B cells by interacting with bone marrow stromal cells

Blood ◽  
1996 ◽  
Vol 87 (8) ◽  
pp. 3375-3383 ◽  
Author(s):  
T Tsujimoto ◽  
IA Lisukov ◽  
N Huang ◽  
MS Mahmoud ◽  
MM Kawano
Keyword(s):  
Bone Marrow ◽  
B Cells ◽  
B Cell ◽  
Cell Survival ◽  
Cell Lines ◽  
Stromal Cells ◽  
Plasma Cells ◽  
Myeloma Cell ◽  
Myeloma Cells ◽  
B Cell Survival

By using two-color phenotypic analysis with fluorescein isothiocyanate- anti-CD38 and phycoerythrin-anti-CD19 antibodies, we found that pre-B cells (CD38+CD19+) signifcantly decreased depending on the number of plasma cells (CD38++CD19+) in the bone marrow (BM) in the cases with BM plasmacytosis, such as myelomas and even polyclonal gammopathy. To clarify how plasma cells suppress survival of pre-B cells, we examined the effect of plasma cells on the survival of pre-B cells with or without BM-derived stromal cells in vitro. Pre-B cells alone rapidly entered apoptosis, but interleukin-7 (IL-7), a BM stromal cell line (KM- 102), or culture supernatants of KM-102 cells could support pre-B cell survival. On the other hand, inhibitory factors such as transforming growth factor-beta1 (TGF-beta1) and macrophage inflammatory protein- 1beta (MIP-1beta) could suppress survival of pre-B cells even in the presence of IL-7. Plasma cells alone could not suppress survival of pre- B cells in the presence of IL-7, but coculture of plasma cells with KM- 102 cells or primary BM stromal cells induced apoptosis of pre-B cells. Supernatants of coculture with KM-102 and myeloma cell lines (KMS-5) also could suppress survival of pre-B cells. Furthermore, we examined the expression of IL-7, TGF-beta1, and MIP-1beta mRNA in KM-102 cells and primary stromal cells cocultured with myeloma cell lines (KMS-5). In these cells, IL-7 mRNA was downregulated, but the expression of TGF- beta1 and MIP-1beta mRNA was augmented. Therefore, these results suggest that BM-derived stromal cells attached to plasma (myeloma) cells were modulated to secrete lesser levels of supporting factor (IL- 7) and higher levels of inhibitory factors (TGF-beta1 and MIP-1beta) for pre-B cell survival, which could explain why the increased number of plasma (myeloma) cells induced suppression of pre-B cells in the BM. This phenomenon may represent a feedback loop between pre-B cells and plasma cells via BM stromal cells in the BM.

Amphiregulin Is Produced by Myeloma Cells and Is Involved in Tumor-Environment Interactions in Multiple Myeloma.

Blood ◽  
2004 ◽  
Vol 104 (11) ◽  
pp. 4306-4306
Author(s):  
Karène Mahtouk ◽  
Dirk Hose ◽  
Thierry Reme ◽  
John De Vos ◽  
Michel Jourdan ◽  
...  
Keyword(s):  
Multiple Myeloma ◽  
Bone Marrow ◽  
Growth Factors ◽  
Plasma Cells ◽  
Myeloma Cell ◽  
Erbb Receptors ◽  
Heparin Binding ◽  
Myeloma Cells ◽  
Heparin Binding Growth Factors ◽  
Egf Family

Abstract Multiple myeloma (MM) is characterized by the accumulation of clonal malignant plasma cells in the bone marrow. One of the hallmarks of plasma cells is the expression of the heparan-sulfate proteoglycan syndecan-1. In epithelial cells, syndecan-1 plays a major role as a coreceptor for heparin-binding growth factors and chemokines. This stresses that heparin-binding growth factors may play a major role in the biology of MM cells. Recently we have demonstrated that heparin-binding EGF-like growth factor (HB-EGF), one of the ten members of the Epidermal Growth Factor (EGF) family, is produced by the tumor microenvironment and is able to trigger myeloma cell growth. As amphiregulin (AREG) is another member of the EGF family that also binds heparan-sulphate chains, we investigated its role in MM. We looked for AREG expression on a panel of 7 normal plasmablastic cells (PPCs), 7 normal bone marrow plasma cells (BMPCs), purified MM cells from 65 patients and 20 myeloma cell lines (HMCLs), with Affymetrix U133A+B microarrays. We showed that primary MM cells overexpress AREG compared to normal BMPCs and PPCs. We then investigated the expression of the ErbB receptors with real-time RT-PCR. Myeloma cells variably expressed the 4 ErbB receptors. Normal BMPCs also expressed ErbB1 and ErbB2 unlike PPCs that did not express any ErbB receptors. We demonstrated that the high AREG expression by primary myeloma cells may have a dual effect. On the one hand, AREG stimulated IL-6 production and growth of bone-marrow stromal cells that highly express the AREG ErbB1 receptor. On the other hand, AREG could promote HMCL proliferation, suggesting that a functional autocrine loop involving AREG and ErbB receptors is involved in MM cell growth. Finally, we looked for the effect of ErbB inhibitors on MM cells of 14 patients cultured for 6 days together with their bone marrow environment. A pan-ErbB inhibitor (PD-169540, Pfizer) and an ErbB1-inhibitor (IRESSA, Astrazeneca) induced strong MM cell apoptosis in respectively 71% of patients (10 of 14) and 29% of patients (4 of 14). Of major interest, when PD169540 or IRESSA were combined with dexamethasone, they induced a dramatic myeloma cell death (respectively 92% and 69% inhibition of MM cell survival), while non-myeloma cells were unaffected. Thus ErbB activation is critical to trigger MM-cell survival in short-term culture. In conclusion, our findings provide evidence for a major role of AREG and HB-EGF in the biology of multiple myeloma and identify ErbB receptors as putative therapeutic targets. These data emphasize the interest of clinical evaluation of specific-ErbB-inhibitors in patients with MM, either used alone or in combination with dexamethasone.

Sign in / Sign up

Export Citation Format

Share Document