Bone marrow angiogenesis in patients with active multiple myeloma.

Factor VIII-related antigen (FVIII-RA)-positive microvessel areas were measured by both immunohistochemistry and computerized image analysis in patients with active multiple myeloma (MM), nonactive MM, and monoclonal gammopathies of undetermined significance (MGUS). A five-to sixfold larger area was found in patients with active MM compared to the other two groups. Aquaporin 1 (AQP1)-positive microvessel areas, measured with the same techniques on adjacent tissue sections, were also increased in active MM, and tended to be larger than and closely correlated with the FVIII-RA areas. Numerous mast cells were found in the bone marrow of active MM patients, and counts were strictly correlated with the microvessel density. The conditioned medium (CM) of bone marrow plasma cells from active MM patients stimulated endothelial cell proliferation and chemotaxis, monocyte chemotaxis, and angiogenesis in vivo (assessed by the chick embryo chorioallantoic membrane [CAM] system) more strongly and frequently than the CM of patients with nonactive MM and MGUS. Immunoassay of plasma cell lysates gave significantly higher levels of fibroblast growth factor-2 (FGF-2) in patients with active MM than in the other two groups, and a neutralizing anti-FGF-2 antibody inhibited by 46% to 68% the biological activity exerted by the CM in vitro and in the CAM. In situ hybridization of bone marrow plasma cells and zymography of CM showed that patients with active MM express higher levels of matrix metalloproteinase-2 (MMP-2) mRNA and protein than those with nonactive MM and MGUS, whereas MMP-9 expression and secretion overlapped in all groups. Overall data indicate that patients with active MM represent the vascular phase of plasma cell tumors that is induced, at least partly, through FGF-2 and MMP-2. Mast cells possibly contribute to the vascular phase via angiogenic factors in their secretory granules. Both angiogenesis and MMP-2 secretion can account for intramedullary and extramedullary spreading of plasma cells in patients with active MM.     

Thalidomide metabolites in mice and patients with multiple myeloma.

PURPOSE:This research examines the profile of metabolites of thalidomide that are formed in refractory multiple myeloma patients undergoing thalidomide therapy in comparison with those that are detected in healthy mice. EXPERIMENTAL DESIGN: Urine or plasma samples from patients during thalidomide therapy (100-400 mg daily), or from mice treated i.p. (100 mg/kg) or p.o. with thalidomide (50 mg/kg) were analyzed using liquid chromatography-mass spectrometry. Metabolites in each of the peaks observed in the UV- and mass spectrometry-detected high-performance liquid chromatography traces were identified by comparison of retention times and spectra with those of authentic standards. RESULTS: Plasma and urine samples from mice 4 h after treatment with thalidomide contained eight major metabolites formed by hydroxylation and/or hydrolysis of thalidomide. In contrast, urine samples from seven multiple myeloma patients at steady state levels of thalidomide therapy showed the presence of only three hydrolysis breakdown products and no hydroxylated metabolites. CONCLUSIONS: Our results show that thalidomide metabolite profiles in multiple myeloma patients differ considerably from those in mice. The lack of measurable hydroxylated metabolites in urine and in 1 case plasma of these patients suggests that such metabolites are not responsible for the therapeutic effects of thalidomide in multiple myeloma. We suggest that thalidomide may act directly, down-regulating growth factors essential for multiple myeloma growth.     

Bortezomib and zoledronic acid on angiogenic and vasculogenic activities of bone marrow macrophages in patients with multiple myeloma

Bone marrow neovascularisation supports plasma cell tumour progression in patients with multiple myeloma (MM), and is partially sustained by bone marrow macrophages through their angiogenic and vasculogenic activities. As such, macrophages may be a target for antivascular treatment in MM. Here, we show that bortezomib (BZ) and zoledronic acid (ZOL) display distinct and synergistic inhibitory effects on cell proliferation, adhesion, migration and expression of angiogenic cytokines (i.e.: VEGF, bFGF, HGF and PDGF). Similar effects were found on capillarogenic organisation and expression of vascular markers in cells which became vasculogenic. VEGFR2 and ERK1/2 phosphoactivation as well as NF-κB activity were also inhibited. Overall these data provide evidence that the exposure of bone marrow macrophages in MM during the treatment with ZOL and BZ, alone and or in combination, impacts their angiogenic and vasculogenic properties, suggesting that these cells may be considered as a target of both drugs in MM patients.     

Syndecan-1 promotes the angiogenic phenotype of multiple myeloma endothelial cells

Angiogenesis is considered a hallmark of multiple myeloma (MM) progression. In the present study, we evaluated the morphological and functional features of endothelial cells (ECs) derived from bone marrow (BM) of patients affected by MM (MMECs). We found that MMECs compared with normal BM ECs (BMECs) showed increased expression of syndecan-1. Silencing of syndecan-1 expression by RNA interference technique decreased in vitro EC survival, proliferation and organization in capillary-like structures. In vivo, in severe combined immunodeficient mice, syndecan-1 silencing inhibited MMEC organization into patent vessels. When overexpressed in human umbilical vein ECs and BMECs, syndecan-1 induced in vitro and in vivo angiogenic effects. Flow-cytometric analysis of MMECs silenced for syndecan-1 expression indicated a decreased membrane expression of vascular endothelial growth factor (VEGF) receptor-2 (VEGFR-2). Immunoprecipitation and confocal analysis showed colocalization of VEGFR-2 with syndecan-1. Absence of nuclear translocation of VEGFR-2 in syndecan-1-knockdown cells together with the shift from perinuclear localization to recycling compartments suggest a role of syndecan-1 in modulation of VEGFR-2 localization. This correlated with an in vitro decreased VEGF-induced invasion and motility. These results suggest that syndecan-1 may contribute to the highly angiogenic phenotype of MMECs by promoting EC proliferation, survival and modulating VEGF-VEGFR-2 signalling.     

Importance of the bone marrow microenvironment in inducing the angiogenic response in multiple myeloma

Tumor microenvironment is essential for tumor cell proliferation, angiogenesis, invasion and metastasis through its provision of survival signals, secretion of growth and pro-angiogenic factors, and direct adhesion molecule interactions. This review examines its importance in the induction of an angiogenic response in multiple myeloma (MM). The encouraging results of preclinical and clinical trials in which MM has been treated by targeting the tumor microenvironment are also discussed.     

Allogeneic bone marrow transplantation in multiple myeloma.

The use of high-dose chemoradiotherapy with allogeneic hemopoietic stem cell support for the treatment of MM began about a decade ago. Because this procedure has been performed increasingly and because larger numbers of patients are being followed for longer periods of time, the proper role of allogeneic BMT in this setting is becoming clearer. Data available thus far indicate that such an approach results in a complete remission rate of at least 50% to 60%, and even higher if applied as consolidation treatment in the remission phase, a transplant-related mortality reported as 40% to 50% and a long-term survival plateau at around 40%. The 40% 5-year probability of relapse-free survival is considerably higher than that observed following autologous BMT and may result from an allogeneic graft-versus-tumor effect (graft versus myeloma) similar to the well-recognized graft-versus-leukemia effect. Although follow-up is still too short to clearly identify the likelihood of cure for MM allotransplant recipients, a certain number of them are currently long-term, disease-free survivors and--we hope--cured. These promising results and the incurability of MM with conventional chemotherapy should, therefore, encourage further application of allogeneic BMT to selected patients with unfavorable prognostic features. Continued efforts to reduce the morbidity and mortality related to the procedure, as well as to design effective pretransplant regimens with lower extramedullary toxicity and to identify those patients most likely to benefit from BMT, will improve the value of allogeneic BMT in MM.     

2-甲氧基雌二醇对多发性骨髓瘤患者骨髓细胞的影响

目的:探讨2-甲氧基雌二醇(2ME2)对多发性骨髓瘤患者骨髓瘤细胞及造血前体细胞凋亡的影响。方法:采用DNA片断原位末端标记(TUNEL法)检测多发性骨髓瘤患者骨髓瘤细胞及造血前体细胞凋亡。结果:14例多发性骨髓瘤患者骨髓瘤细胞经1、4、16μmol/L2-甲氧基雌二醇作用48小时后,凋亡率分别为(10.5±1.2)%、(21.2±2.3)%、(36.8±3.6)%,呈现剂量依赖性。经统计学分析,各组之间及与空白对照组相比,差异显著(P<0.05)。骨髓中粒系、红系、淋巴系细胞出现凋亡较少,经统计学分析,各组之间及与空白对照组相比,无明显差异(P>0.05)。相同的2ME2浓度条件下,骨髓中粒系、红系、淋巴系细胞凋亡率与骨髓瘤细胞组凋亡率相比,差异显著(P<0.05)。结论:2-甲氧基雌二醇可选择性诱导骨髓瘤患者骨髓中骨髓瘤细胞凋亡,对骨髓瘤患者骨髓中粒系、红系、淋巴系细胞影响很小。     

Phenotypic and functional characterization of bone marrow mesenchymal stem cells derived from patients with multiple myeloma.

Multiple myeloma (MM) is a B-cell neoplasia caused by the proliferation of clonal plasma cells, primarily in the bone marrow (BM). The role of the BM microenvironment in the pathogenesis of the disease has been demonstrated, especially for the survival and growth of the myeloma plasma cells. Functional characterization of the major component of the BM microenvironment, namely the recently characterized mesenchymal stem cells (MSCs), was never performed in MM. Based on a series of 61 consecutive patients, we evaluated the ability of MSCs derived from myeloma patients to differentiate into adipocytes and osteocytes, inhibit T-cell functions, and support normal hematopoiesis. MSCs phenotypic characterization and quantification of interleukin-6 (IL-6) secretion were also performed. As compared to normal MSCs, MSCs from MM patients exhibited normal phenotype, differentiation capacity and long-term hematopoietic support, but showed reduced efficiency to inhibit T-cell proliferation and produced abnormally high amounts of IL-6. Importantly, these characteristics were observed in the absence of any detectable tumor plasma cell. Chromosomal analysis revealed that MM patients MSCs were devoid of chromosomal clonal markers identified in plasma cells. MM MSCs present abnormal features that may participate in the pathogenesis of MM.     

Concerning the condition of the bone marrow in patients with multiple myeloma

The bone marrow of 48 patients with multiple myeloma was studied prior to therapy. A relationships was established between cluster formation rate, on the one hand, and the numbers of myelocaryocytes, erythrocytes and circulating immune complexes, on the other. In patients with stage III disease, the diminished cellularity of the marrow was due to decreased levels of granulocytes and normocytes. Moreover, those patients revealed fewer erythroclastic marrow clusters. Similar changes in the granulocytic component of hemopoiesis were present in those who died within earlier stages (20 months) after the beginning of therapy. It is suggested that diminished granulocyte pool alongside reduced cluster formation rate may play a role in infectious complication development.     

Survivin在多发性骨髓瘤患者骨髓细胞中的表达及其临床意义

背景与目的:Survivin是凋亡抑制蛋白家族成员之一,在多种恶性肿瘤中高表达,但在正常成人分化组织无表达。其表达与多种肿瘤的预后及肿瘤对放、化疗的耐受有关。本研究旨在通过检测Survivin在正常人、初治及复发/难治多发性骨髓瘤(multiplemyeloma,MM)患者骨髓细胞及骨髓瘤细胞系KM3中的表达,以揭示Survivin在骨髓瘤中的表达与耐药及疗效的关系。方法:RT-PCR和Westernblot法检测29例MM患者(其中初治17例,复发/难治12例)、9例正常人骨髓标本及KM3细胞系中SurvivinmRNA和蛋白质水平表达。结果:骨髓瘤细胞系KM3高表达Survivin。SurvivinmRNA在正常人、初治和难治/复发MM患者骨髓细胞中阳性率分别为22.2%、70.5%和83.3%,表达水平(Survivin/β-actin比值)分别为0.06±0.04、0.31±0.14和0.69±0.24,骨髓瘤患者表达率和表达水平显著高于正常人(P<0.01),而难治/复发MM组表达水平高于初治组(P<0.05)。所有的正常人标本中均未检测到Survivin蛋白,在初治和难治/复发MM组Survivin蛋白阳性率分别为41.1%和58.3%(P>0.05),表达水平(Survivin/α-tubulin半定量比值)分别为0.11±0.07和0.21±0.12,难治/复发MM组明显为高(P<0.05)。17例初治患者中,7例Survivin阳性者4例部分缓解(partialresponse,PR),1例微小反应(minorresponse,MR),2例无变化(nochange,NC),有效率[完全缓解(completeresponse,CR) PR MR]71.4%;10例Survivin阴性者中2例CR,4例PR,2例MR,2例NC,有效率80%,略高于阳性组。但统计学分析未发现两组有效率存在显著性差异。结论:Survivin在骨髓瘤患者中的高表达可能是部分患者对化疗不敏感的原因之一,由于Survivin仅特异性表达于骨髓瘤细胞,Survivin可作为逆转骨髓瘤细胞耐药治疗中的潜在靶点。     

Upregulation of matrix metalloproteinase-9 in murine 5T33 multiple myeloma cells by interaction with bone marrow endothelial cells

MM is a B-cell malignancy mainly characterized by monoclonal expansion of plasma cells in the BM, presence of paraprotein in serum and occurrence of osteolytic bone lesions. MMPs are a family of proteolytic enzymes that can contribute to cancer growth, invasion, angiogenesis, bone degradation and other processes important in the pathogenesis of MM. We investigated MMP-9 production in the 5T33MM murine model. Expression of MMP-9 protein in supernatant and cell extracts was analyzed by gelatin zymography. The in vitro, stroma-independent variant 5T33MMvt showed no protein expression of MMP-9 in contrast to in vivo growing MM cells, 5T33MMvv. However, when 5T33MMvt cells were injected into naive mice and isolated after tumor take (5T33MMvt-vv), they secreted a significant amount of MMP-9. These results were confirmed by specific staining of cytospins with an anti-MMP-9 antibody. The MMP-9 production by 5T33MMvt-vv cells disappeared when the cells were recultured in vitro. These data demonstrated that upregulation of MMP-9 occurs in vivo and that this process is dependent on the microenvironment. Cocultures of 5T33MMvt cells with STR10 BMECs induced MMP-9 in MM cells, as determined by both gelatin zymography and flow-cytometric analysis. In conclusion, our results demonstrate that MMP-9 production by MM cells is upregulated in vivo by the interaction of MM cells with BMECs.     

Combination therapy of Thalidomide and Peginterferon in patients with progressive multiple myeloma.

The rationale of this study was to investigate the safety andtherapeutic effect of a combination therapy of Thalidomide (Thal)and IFN-. Both agents are known to exert immunomodulatory andanti-angiogenic effects and are used for therapy in multiplemyeloma (MM) [1]. In a phase I/II study, Thal was started ata dose     

Adherence of multiple myeloma cells to bone marrow stromal cells upregulates vascular endothelial growth factor secretion: therapeutic applications.

Increased angiogenesis has recently been recognized in active multiple myeloma (MM). Since vascular endothelial growth factor (VEGF) and basic fibroblast growth factor (bFGF) are two key mediators of angiogenesis, we characterized the production of VEGF, b-FGF and interleukin-6 (IL-6) (a MM growth and survival factor) in MM cell lines and Epstein-Barr virus (EBV) transformed B cell lines from MM patients, patient MM cells, as well as bone marrow stromal cells (BMSCs) from normal healthy donors and MM patients. We detected secretion of VEGF, but no bFGF and IL-6, in MM cell lines (MM.1S, RPMI 8226 and U266); EBV transformed B cell lines from MM patients (IM-9, HS-Sultan and ARH77); MM cell lines resistant to doxorubicin (RPMI-DOX40), mitoxantrone (RPMI-MR20), melphalan (RPMI-LR5) and dexamethasone (MM.1R); and patient MM cells (MM1 and MM2). BMSCs from MM patients and normal donors secreted VEGF, b-FGF and IL-6. Importantly, when MM cells were adhered to BMSCs, there was a significant increase in VEGF (1.5- to 3.1-fold) and IL-6 (1.9- to 56-fold) secretion. In contrast, the bFGF decreased in co-cultures of BMSCs and MM cells. Paraformaldehyde fixation of BMSCs or MM cells prior to adhesion revealed that VEGF was produced both from BMSCs and MM cells, though it may come primarily from BMSCs in some cultures. IL-6 was produced exclusively in BMSCs, rather than MM cells. Moreover, when MM cells were placed in Transwell insert chambers to allow their juxtaposition to BMSCs without cell to cell contact, induction of VEGF and IL-6 secretion persisted, suggesting the importance of humoral factors. Addition of exogenous IL-6 (10 ng/ml) increased VEGF secretion by BMSCs. Conversely, VEGF (100 ng/ml) significantly increased IL-6 secretion by BMSCs. Moreover, anti-human VEGF (1 microg/ml) and anti-human IL-6 (10 microg/ml) neutralizing antibodies reduced IL-6 and VEGF secretion, respectively, in cultures of BMSCs alone and co-cultures of BMSCs and MM cells. Finally, thalidomide (100 microM) and its immunomodulatory analog IMiD1-CC4047 (1 microM) decreased the upregulation of IL-6 and VEGF secretion in cultures of BMSCs, MM cells and co-cultures of BMSCs with MM cells. These data demonstrate the importance of stromal-MM cell interactions in regulating VEGF and IL-6 secretion, and suggest additional mechanisms whereby thalidomide and IMiD1-CC4047 act against MM cells in the BM millieu.     

Autologous bone marrow transplantation for multiple myeloma.

Intensive cytotoxic chemotherapy is capable of more marked tumor cytoreduction including true complete remissions in multiple myeloma. Use of autologous marrow and blood stem cells as well as growth factors has reduced the risk of infection and severe extramedullary toxicities.     

Thalidomide in the management of multiple myeloma.

A phase II trial of thalidomide in refractory multiple myeloma was initiated using a dose schedule that escalated from 200 mg/d to 800 mg/d. More than two thirds of patients had cytogenetic abnormalities and more than half had received at least two cycles of high-dose therapy. A paraprotein reduction of at least 25% was noted in 37% of patients and 14% had either a complete remission (CR) or a near CR. No treatment-related mortality was observed. With a median follow-up of almost 2 years, the 2-year event-free survival (EFS) and overall survival (OS) estimates were 15% and 60%, respectively. A reduction of paraprotein levels by greater than 50% was associated with a significant reduction in bone marrow plasmacytosis and beta(2)-microglobulin levels (beta2M), and greater recovery of hemoglobin and IgM levels compared to patients whose paraprotein was reduced by a lesser degree. Responses occurred more frequently among patients with a lower plasma cell labeling index (PCLI) and normal cytogenetics. Comparing response and survival by thalidomide dose for low- and high-risk groups revealed a thalidomide dose-response effect in the high-risk group of patients. The virtual absence of myelosuppressive toxicity, except in heavily pretreated patients with compromised bone marrow function, suggests that thalidomide is an ideal agent to be used in combination with cytotoxic agents and dexamethasone. Several trials are currently underway at the Arkansas Myeloma and Transplantation Research Center to determine the clinical benefit of adding thalidomide to post-transplant salvage therapy and in the upfront management of patients.     

In vitro growth of hematopoietic progenitors and stromal bone marrow cells from patients with multiple myeloma

In the present study we have determined the content of hematopoietic and stromal progenitors in multiple myeloma (MM) bone marrow, and assessed their in vitro growth. Marrow cells were obtained from 17 MM patients at the time of diagnosis, and from 6 hematologically normal subjects. When mononuclear cells (MNC) from MM marrow were cultured, reduced numbers of hematopoietic progenitors were detected and their growth in long-term cultures was deficient, as compared to cultures of normal cells. When cell fractions enriched for CD34⁺ Lin⁻ cells were obtained, the levels of hematopoietic progenitors from MM marrow were within the normal range, and so was their growth kinetics in liquid suspension cultures. The levels of fibroblast progenitors in MM were not statistically different from those in normal marrow; however, their proliferation potential was significantly reduced. Conditioned media from MM-derived MNC and stroma cells contained factors that inhibited normal progenitor cell growth. Our observations suggest that hematopoietic progenitors in MM marrow are intrinsically normal; however, their growth in LTMC may be hampered by the presence of abnormal accessory and stroma cells. These results suggest that besides its role in the generation of osteolytic lesions and the expansion of the myeloma clone, the marrow microenvironment in MM may have a negative effect on hematopoiesis.