Biological aspects of angiogenesis in multiple myeloma

Multiple myeloma (MM) is a hematological malignancy characterized by the aberrant expansion of malignant plasma cells within the bone marrow (BM). One of the hallmarks of this disease is the close interaction between myeloma cells and neighboring cells within the BM. Angiogenesis, through the activation of endothelial cells, plays an essential role in MM biology. In the current review, we describe the angiogenesis process in MM by identifying the interacting cells, the pro- and anti-angiogenic cytokines modulated, and the extracellular matrix degrading proteases liable to participate in the pathophysiology. Finally, we highlight the impact of hypoxia (through hypoxia-inducible factor-1) and constitutive activation of nuclear factor-κB in this tumor-induced neo-vascularization.     

Clinical characteristics of bone disease in multiple myeloma and clinical significance of monitoring bone metabolic markers

<正>Objective To observe the clinical characteristics of bone disease in patients with multiple myeloma(MM)and the clinical significance of monitoring bone metabolic markers.Methods The data of 178 MM case newly diagnosed in Beijing Ji Shui Tan Hospital from January 2009to June 2014 were reviewed to analyze the types and classification of bone disease and to observe the clinical char-     

sVE-cadherin and sCD146 serum levels in patients with multiple myeloma

The role of angiogenesis in multiple myeloma (MM) pathogenesis is well established. Angiogenesis is linked to the functional state of endothelial junctions that are modulated by the growth and activation of endothelial cells. CD146 and vascular endothelial-cadherin (VE-cadherin) are cell adhesion molecules localized at the endothelial junction. The aim of the study was to assess sVE-cadherin and sCD146 serum levels in MM patients. Forty-six untreated patients with MM were included in this study. In addition, 23 of 46 patients were analyzed again in partial remission after initial chemotherapy. Twenty-two samples from healthy volunteers were evaluated as the control. There was no significant difference in sCD146 level between MM patients and the control (511 +/- 177.2 vs. 460.9 +/- 156.9 ng/ml respectively). In untreated MM patients, sVE-cadherin level was significantly higher than in the control (1.36 +/- 0.55 vs. 0.63 +/- 0.56 ng/ml respectively; P < 0.05). In untreated MM patients, sVE-cadherin level was significantly higher than in MM patients in partial remission (1.36 +/- 0.55 vs. 0.5 +/- 0.33 respectively; P < 0.05). sVE-cadherin but not sCD146 serum level was increased in untreated MM patients and decreases after chemotherapy in patients in partial remission. VE-cadherin may reflect intensity of angiogenesis in MM and may be useful in prognosis of response to treatment.     

Bone marrow angiogenesis and progression in multiple myeloma

Tumour growth is angiogenesis-dependent. We found a high correlation between the extent of bone marrow angiogenesis, evaluated as microvessel area, and the proliferating (S-phase) fraction of marrow plasma cells, evaluated as labelling index (LI), in patients with multiple myeloma (MM) and in those with monoclonal gammopathies of undetermined significance (MGUS). Angiogenesis itself was significantly associated with active as opposed to non-active MM and MGUS. The highest microvessel area accompanied rapidly progressive MM with the highest LI. When a cut-off value of 2% or greater of the microvessel area was used, most patients with active MM were classified correctly. The risk of active disease in patients with MM increased in parallel with the microvessel area. A causal relationship between plasma cell growth, activity phase in MM and marrow angiogenesis is suggested. Since angiogenesis proceeds in step with the enlargement of plasma cell tumours and the activity phase in MM, its measurement could be a useful prognostic marker in patients with plasma cell proliferative disorders.     

Clinical significance of serum erythropoietin levels in patients with multiple myeloma]

Serum erythropoietin (Epo) levels were measured in 53 patients with multiple myeloma (MM), 49 normal subjects and 53 patients with some hematological diseases including aplastic anemia (AA), iron deficiency anemia, etc. to study the significance of erythropoietin in anemia of MM. The serum Epo level was 72.0 +/- 94.4 mIU/ml (mean +/- SD) in MM patients, which was significantly higher than in normal subjects (24.1 +/- 6.1 mIU/ml), but lower than in AA patients (7069.9 +/- 9406 mIU/ml). A significant inverse correlation was found between the hemoglobin (Hb) levels and the logarithmic values of serum Epo levels (r = -0.543, p < 0.05) in MM patients. This inverse correlation was stronger (r = -0.636, p < 0.05) in MM patients without renal dysfunction than in whole MM patients, while no correlation was observed in MM patients with renal dysfunction. These results indicate that MM patients with renal dysfunction have a low ability to synthesize Epo and that the supplemental therapy of recombinant Epo is effective to improve their anemia. In addition, the circadian rhythm of serum Epo level was lower in the morning than in the afternoon in both MM patients and normal controls. Serum Epo levels after chemotherapy in MM patients were elevated temporarily and then decreased in spite of no change of blood Hb level.     

Clinical significance of cyclooxygenase-2 (COX-2) in multiple myeloma

Several biological and clinical considerations suggest the involvement of cyclooxygenase-2 (COX-2), the key enzyme of prostaglandin (PG) synthesis, in the pathogenesis and progression of haematological malignancies. Despite the wealth of data concerning COX-2 expression, only limited information is available on multiple myeloma (MM). Using standard immunohistochemistry we therefore evaluated COX-2 protein expression in samples from 57 patients with a primary diagnosis of MM. Time to progression and a variety of clinicopathological features were evaluated by the Kaplan-Meier method and the Cox regression model. In addition, COX-2 expression was evaluated by staining bone marrow from healthy donors and 11 patients with MGUS. Overall, 31 MM samples (54%) expressed COX-2. Positivity for COX-2 was unrelated to stage or clinical or molecular features of the disease. However, patients with COX-2 positive tumours experienced a significantly shorter time to progression (17 vs 30 months, p = 0.037). In summary, COX-2 is frequently expressed in MM and correlates with shorter progression-free survival.     

Fibrinolytic activity in multiple myeloma

The incidence of thromboembolic events is high as a result of disease, disease-related complications, and therapy in multiple myeloma (MM). In patients with hematologic tumors, impaired fibrinolysis may be present and may contribute to the development of thrombotic complications. Therefore, we designed a study to investigate fibrinolytic activity in MM. We compared plasma levels of interleukin (IL)-6, C-reactive protein (CRP), IL-1beta, IL-11, tissue plasminogen activator (tPA) activity, plasminogen activator inhibitor-1 (PAI-1) activity, and global fibrinolytic capacity (GFC) in patients with MM (n = 66) and in control subjects (n = 18). The prevalence of venous thromboembolism was 4.5%, with a median follow-up period of 7 months in our myeloma group. Results are given as mean (median, range). Plasma levels of IL-6 (8.27 +/- 0.74 [9.65, 0.90-13.32] pg/mL versus 2.64 +/- 0.66 [1.80, 0.10-11.86] pg/mL, P < 0.001), CRP (45.57 +/- 9.92 [21.00, 1.34-330.00] mg/L versus 1.96 +/- 0.50 [1.05, 0.19-8.03] mg/L, P < 0.001), PAI-1 (7.40 +/- 0.67 [5.57, 2.40-31.80] IU/mL versus 4.73 +/- 0.65 [3.60, 2.32-11.00] IU/mL, P < 0.01), GFC score (1.90 +/- 0.02 [2, 1-3] versus 2.50 +/- 0.14 [3, 1-3], P < 0.001) were increased compared with controls. In patients with MM, the level of IL-6 was positively correlated with CRP (r = 0.66, P < 0.001), IL-1beta (r = 0.29, P < 0.05), and PAI-1 (r = 0.35, P < 0.01) and negatively correlated with GFC (r = -0.37, P < 0.01). CRP level was positively correlated with plasma PAI-1 level (r = 0.40, P < 0.01) and negatively correlated with GFC (r = -0.44, P < 0.001). A significant negative correlation between PAI-1 level and GFC (r = -0.75, P < 0.001) was also detected. IL-1beta levels were negatively correlated with tPA level (r = -0.26, P < 0.05). These results suggest that patients with myeloma have a decreased fibrinolytic activity mainly because of increased PAI-1 activity. In MM, increased PAI-1 activity seems to be related with elevated IL-6 level. MM should be considered as a hypercoagulable state as a result of both increased procoagulant activity and decreased fibrinolytic activity. Achieving a plateau by means of conventional chemotherapies does not improve the decreased fibrinolytic activity.     

Bone marrow angiogenesis and circulating plasma cells in multiple myeloma

Bone marrow (BM) angiogenesis is increased in multiple myeloma (MM) and has prognostic significance. The presence of circulating plasma cells (PCs) in MM is associated with a poorer prognosis. We examined BM biopsies obtained at diagnosis of MM for angiogenesis, and correlated the microvessel density (MVD) with the presence of circulating PCs. There was a positive correlation between the absolute number of circulating PCs and the mean MVD. This relationship was independent of the disease activity and of the PC burden in the marrow. The increased angiogenesis may promote plasma cell proliferation and enable PC migration into the circulation.     

Renal disease in multiple myeloma

Multiple myeloma is a malignant tumor of B (plasma) cells that is characterized by monoclonal immunoglobulin production. The incidence of myeloma is increasing worldwide, particularly among individuals of advanced age. Renal impairment at diagnosis is present in approximately 20% of patients with myeloma, and uremia is the cause of death in about 15%. Several renal disorders may be present in myeloma. Bence Jones cast nephropathy (BJCN), acute tubular necrosis, and “nonspecific” tubulointerstitial nephritis are related to nephrotoxic light chains in urine. Hypercalcemia potentiates the toxicity of urinary light chains. The tissue deposition of light chains leads to renal AL-amyloidosis or light chain deposition nephropathy (LCDN). In necropsy series, the incidence of BJCN, renal AL-amyloidosis, and LCDN is about 30%, 10%, and 4%, respectively. Clinically, urinary nephrotoxic light chain-associated disorders and LCDN are usually manifested in chronic or acute renal failure. The nephrotic syndrome is commonly due to renal AL-amyloidosis. Most cases of end-stage renal failure are due to BJCN and LCDN. The basic therapy of renal impairment is hydration, forced diuresis, and initiation of chemotherapy. Diphosphonates are effective new tools for the correction of hypercalcemia, and decrease the incidence of pathological fractures. In acute renal failure, plasma exchange in association with forced diuresis, dialysis, and chemotherapy may improve renal function. End-stage renal failure requires maintenance renal replacement therapy. In myeloma patients with advanced age, the limits of medical intervention should be judged individually. Particular attention should be paid to the supportive care of the patients.     

sVE‐cadherin and sCD146 serum levels in patients with multiple myeloma

The role of angiogenesis in multiple myeloma (MM) pathogenesis is well established. Angiogenesis is linked to the functional state of endothelial junctions that are modulated by the growth and activation of endothelial cells. CD146 and vascular endothelial‐cadherin (VE‐cadherin) are cell adhesion molecules localized at the endothelial junction. The aim of the study was to assess sVE‐cadherin and sCD146 serum levels in MM patients. Forty‐six untreated patients with MM were included in this study. In addition, 23 of 46 patients were analyzed again in partial remission after initial chemotherapy. Twenty‐two samples from healthy volunteers were evaluated as the control. There was no significant difference in sCD146 level between MM patients and the control (511 ± 177.2 vs. 460.9 ± 156.9 ng/ml respectively). In untreated MM patients, sVE‐cadherin level was significantly higher than in the control (1.36 ± 0.55 vs. 0.63 ± 0.56 ng/ml respectively; P < 0.05). In untreated MM patients, sVE‐cadherin level was significantly higher than in MM patients in partial remission (1.36 ± 0.55 vs. 0.5 ± 0.33 respectively; P < 0.05). sVE‐cadherin but not sCD146 serum level was increased in untreated MM patients and decreases after chemotherapy in patients in partial remission. VE‐cadherin may reflect intensity of angiogenesis in MM and may be useful in prognosis of response to treatment.     

Clinical significance of vascular endothelial growth factor and hepatocyte growth factor in multiple myeloma

Angiogenesis is a crucial process in the progression of multiple myeloma (MM). Vascular endothelial growth factor (VEGF) and hepatocyte growth factor (HGF) are multifunctional cytokines that potently stimulate angiogenesis including tumour neovascularization. Serum levels of VEGF and HGF were measured in 52 patients with MM by enzyme-linked immunosorbent assay (ELISA). Serum levels of VEGF and HGF were elevated in MM patients compared with healthy controls (VEGF: mean 0.31 ng/ml and 0.08 ng/ml respectively, P < 0.01; HGF: mean 2.17 ng/ml and 0.45 ng/ml, respectively, P < 0.001). In serial samples taken after chemotherapy, serum VEGF and HGF levels were correlated with M-protein levels. Serum levels of VEGF were higher in patients with extramedullary plasmacytomas than in patients without them (P < 0.05). They were also significantly higher in a group of patients who showed poor response to chemotherapy (P < 0.01). Serum levels of HGF were higher in patients with complications such as anaemia, hypercalcaemia and amyloidosis than in patients without these complications (P < 0.01, P < 0.05, P < 0.05 respectively). Both serum VEGF and HGF levels were significant predictors of mortality (P = 0.01, P = 0.02, respectively, log-rank test). The present study demonstrated that serum levels of VEGF and HGF are significantly elevated and dependent on the severity of MM, suggesting that measurement of VEGF and HGF may be useful for assessing disease progression and for predicting the response to chemotherapy in MM patients.     

Clinical, morphological, and cell kinetic differences among multiple myeloma, monoclonal gammopathy of undetermined significance, and smoldering multiple myeloma

We reviewed the clinical and morphological findings in 43 cases of monoclonal gammopathy of undetermined significance (MGUS), 9 of smoldering multiple myeloma (SMM), and 23 of overt multiple myeloma (MM). In all cases, the patients' physicians had requested a bone marrow examination because of the possibility of MM. In all 75 cases, 3H-thymidine labeling indices were performed. The plasma cell labeling index correctly classified 62 of the 75 cases (83%). A linear discriminant function combining the labeling index and percentage of plasma cells improved the accuracy to 92% (69/75), or to 95% (71/75) if patients in whom MM developed within 6 mo were considered to have MM. The labeling index was most critical for the differential diagnosis of MM from SMM (p less than 0.001). Serum or urine M-protein level, percentage of plasma cells or lymphocytes in the bone marrow, and plasma cell grade, asynchrony, and nucleolar size failed to discriminate the group with SMM from the group with MM. In patients with MGUS or SMM, a plasma cell labeling index greater than 0.4% warned of impending MM. The plasma cell labeling index is a reliable diagnostic test when applied in cases of monoclonal gammopathy, especially when differentiation from MM is difficult using standard clinical criteria.     

Bone marrow angiogenesis in multiple myeloma: effect of therapy

Recent studies have demonstrated that angiogenesis has a role in haematological malignancies, including multiple myeloma. Multiple myeloma is characterized by inevitable relapse after standard or high-dose chemotherapy. To study the effect of chemotherapy on bone marrow angiogenesis in patients with multiple myeloma, we used two methods to evaluate bone marrow angiogenesis in patients with newly diagnosed multiple myeloma, comparing these findings with those from bone marrow obtained after standard chemotherapy. Before therapy, an increased degree of bone marrow angiogenesis and a high bone marrow plasma cell labelling index (PCLI) were predictive of poorer survival. As estimated by microvessel density (MVD), the median survivals for patients with low-grade, intermediate-grade and high-grade angiogenesis were 77, 30 and 14 months respectively. After therapy, the MVD did not change significantly. However, when patients with at least a partial response were considered separately, they showed a decrease in MVD. Post-therapy PCLI was predictive of survival, but post-therapy MVD was not. There was good correlation between angiogenesis estimated by visual grading and that determined by MVD assessment. We conclude that the degree of bone marrow angiogenesis is a prognostic marker in patients with multiple myeloma and does not decrease significantly after therapy.     

Clinical significance of the appearance of abnormal protein band in patients with multiple myeloma

Multiple myeloma (MM) is characterized by clonal expansion of malignant bone marrow cells producing a unique monoclonal immunoglobulin. The appearance of abnormal protein band (APB) in MM has been reported during follow-up. We aimed to evaluate the clinical characteristics and outcomes of patients with APB in a single center cohort. A total of 377 consecutive MM patients were treated at the Asan Medical Center between January 2002 and December 2012. We compared clinical characteristics and survival outcome between those with and without APB. Of the 377 patients, 34 (9 %) experienced APB. They comprised 18.2 % (27/148) of patients treated with autologous stem cell transplantation (ASCT) and 3.1 % (7/229) of those not receiving ASCT. APB occurred after a median of 7.9 months (range, 2.2–95.7 months) from diagnosis. Immunoglobulin isotypes at diagnosis were as follows: IgG (n?=?10), IgA (n?=?8), IgD (n?=?5), free κ (n?=?4), and free λ (n?=?7). Nine patients experienced a second APB. With a median follow-up of 54.1 months, the median overall survival (OS) has not been reached in patients with APB and was 38.3 months in patients without (P?<?0.001). Multivariate analysis indicated that the development of APB was a significant favorable prognostic factor for OS (hazard ratio 0.21; 95 % confidence interval 0.08–0.52). Serum β₂-microglobulin, albumin, creatinine, and ASCT were also independent prognostic factors for OS. Further investigation is required to establish the mechanisms underlying APB in MM.     

Prognostic significance of stratification systems in multiple myeloma. II. Clinical staging systems

A group of 193 multiple myeloma (MM) patients consisting of cases treated only symptomatically (1959-63) or by nonsystematic monotherapy with Cyclophosphamide or Melphalan (1963-76) and of a subgroup given systematic polychemotherapy and intensive supportive treatment (1976-84) were evaluated for the practical applicability and prognostic relevance of three staging systems. The clinical staging system of Durie and Salmon and the quantitative system of Salmon and Wampler have proved in both subgroups of various periods and with different therapeutic approaches to be well applicable in the clinic allowing the patients to be divided into three prognostically different groups according to the size of the tumor mass. Merlini, Waldenstr?m and Jayakar's staging system has likewise shown relationship to prognosis though the patients could be divided only into two prognostically different groups. It is evident that a deeper knowledge of MM requires nowadays a more comprehensive, complex and prognostically more relevant classification system.     

Synchronous multiple myeloma and Gaucher disease

Pseudo-Gaucher cells can be found in multiple hematologic malignancies, hemoglobinopathies, infections, and multiple storage disorders upon bone marrow aspirate and biopsy; however, Gaucher disease (GD) should be ruled out, particularly when the cytoplasmic inclusions cannot be adequately characterized. It is well known that GD may be associated with monoclonal gammopathies; however, although enzyme replacement therapy (ERT) may result in an improvement in polyclonal gammopathies, its effect on the progression of monoclonal gammopathy of undetermined significance to multiple myeloma (MM) remains uncertain. ERT may improve patient’s cytopenias and facilitate administration of anti-myeloma therapy in patients with concurrent GD and MM; however, the current paucity of data makes it challenging to determine its effect on response to anti-myeloma therapy or the risk of relapse. Hematologists should be familiar with the clinical presentation and diagnosis of GD and its association with monoclonal gammopathies. Here we present a case of synchronous smoldering MM and GD.