Prospective longitudinal study on quality of life in relapsed/refractory multiple myeloma patients receiving second- or third-line lenalidomide or bortezomib treatment.

Treatment advances for multiple myeloma (MM) that have prolonged survival emphasise the importance of measuring patients' health-related quality of life (HRQoL) in clinical studies. HRQoL/functioning and symptoms of patients with relapsed/refractory MM (RRMM) receiving second- or third-line lenalidomide or bortezomib treatment were measured in a prospective European multicentre, observational study at different time points. At baseline, patients in the lenalidomide cohort were frailer than in the bortezomib cohort with more rapid disease progression at study entry (more patients with Eastern Cooperative Oncology Group performance status >2, shorter time from diagnosis, more chronic heart failure, higher serum creatinine levels, more patients with dialysis required). About 40% of the patients receiving lenalidomide discontinued the study in <6 months while 55% in the bortezomib cohort discontinued. No substantial HRQoL deterioration was observed for the first 6 months in patients with RRMM receiving one or the other treatment. For patients still on treatment at study completion (month 6), only the European Organization for Research and Treatment of Cancer Quality-of-Life Core domains of Diarrhoea and Global Health Status/QoL had worsened in the lenalidomide and bortezomib cohorts, respectively. A clinically meaningful deterioration in HRQoL was more often observed for patients who discontinued the study prior to 6 months in the bortezomib cohort than in the lenalidomide cohort.

Bone marrow endothelial cells increase the invasiveness of human multiple myeloma cells through upregulation of MMP-9: evidence for a role of hepatocyte growth factor.

The migration of multiple myeloma (MM) cells from the circulation into the bone marrow (BM) implicates that they must have the capacity to cross the BM endothelium including the subendothelial basement membrane. In this study, human CD138+ MM cells were immunomagnetically isolated from BM samples of MM patients and their invasion through Matrigel, that is, a reconstituted basement membrane, was determined. We demonstrated that primary MM cells have the capacity to transmigrate through basement membrane and that this invasiveness was considerably increased when assessed on Matrigel filters coated with BM endothelial cells (EC) (4LHBMEC line) (transendothelial invasion). The isolated MM cells were shown by zymography to secrete matrix metalloproteinase (MMP)-9 and anti-MMP-9 antibodies inhibited transendothelial invasion, indicating that MMP-9 is involved in this process. BM EC were found to increase the MMP-9 secretion in MM cells, indicating that EC enhance MM cell invasion through stimulation of MMP-9 secretion. BM EC were found to produce hepatocyte growth factor (HGF), and this cytokine also stimulated MMP-9 secretion in MM cells, while anti-HGF antibodies significantly inhibited EC-stimulated MM cell invasion. In summary, our findings provide evidence that MM cell-BM EC interactions enhance the invasion of human MM cells through stimulation of MMP-9 secretion.

Extramedullary plasmacytoma of the cavernous sinus.

We present the case of an 80-year-old male with an history of multiple myeloma (MM) stage I with extramedullary plasmacytoma of the neck, diagnosed 18 months before and in complete remission after radiation therapy and melphalan-prednisone therapy. He was admitted with signs and symptoms characteristic for cavernous sinus syndrome, including diplopia, exophthalmia, ptosis and orbital pain. Magnetic resonance imaging showed a mass lesion in the cavernous sinus, consistent with relapsing extramedullary plasmacytoma. The patient received palliative radiation therapy and high dose dexamethasone, but treatment failed and the patient died. This case represents one of the few reports of extramedullary plasmacytoma of the cavernous sinus. The development of a clinical presentation of cavernous sinus syndrome in a patient with a history of MM or extramedullary plasmacytoma should raise the suspicion of a plasmacytic involvement of the cavernous sinus.

Multiple myeloma, a model for fundamental and clinical research.

Multiple myeloma (MM) is a malignant B cell disorder characterized by the uncontrolled proliferation of monoclonal plasma cells (PC) in the bone marrow (BM) and the presence of monoclonal immunoglobulin in serum and/or urine. Despite recent advances in the understanding of the pathophysiology of MM, the exact etiology of MM still remains unknown. MM cells are characterized by a profound degree of genetic instability with several chromosomal abnormalities. The survival and proliferation of MM cells are largely dependent on a supportive microenvironment. The development and progression of MM can be regard as a multistep process of molecular alterations resulting in uncontrolled growth and therapy resistance. Although considerable progress has been made in the therapy of MM, it still remains an uncurable disease with conventional treatment. Novel therapeutic modalities targeting the MM cell and the microenvironment such as inhibitors of angiogenesis (thalidomide and derivatives, arsenic trioxide) and inhibitors of transcription factor NF-kappa B (proteasome inhibitors) are currently being evaluated in clinical trials and hopefully will result in prolonged disease-free and overall survival.

The Belgian 2010 consensus recommendations for the treatment of multiple myeloma.

Since the introduction of novel therapeutic agents including thalidomide, lenalidomide and bortezomib, the prognosis of multiple myeloma (MM) has significantly improved. These agents have been incorporated into numerous treatment schedules for newly diagnosed as well as more advanced MM patients. Hence, the therapeutic options for MM have become more complex and subject to rapid changes. The multiple myeloma study group (MMSG) of the Belgian Hematological Society has established recommendations for the treatment of MM as based on an extensive review of the literature which is also summarized in this paper. The recommendations are the result of a consensus opinion between haematologists with experience in the field and representing most haematology centres in Belgium. Where applicable, reimbursement criteria are also taken into account. The consensus recommendations should be a reference for use by clinical haematologists in daily practice.

The effects of JNJ-26481585, a novel hydroxamate-based histone deacetylase inhibitor, on the development of multiple myeloma in the 5T2MM and 5T33MM murine models.

Multiple myeloma (MM) is a B-cell malignancy, which often remains incurable because of the development of drug resistance governed by the bone marrow (BM) microenvironment. Novel treatment strategies are therefore urgently needed. In this study, we evaluated the anti-MM activity of JNJ-26481585, a novel 'second-generation' pyrimidyl-hydroxamic acid-based histone deacetylase inhibitor, using the syngeneic murine 5TMM model of MM. In vitro, JNJ-26481585 induced caspase cascade activation and upregulation of p21, resulting in apoptosis and cell cycle arrest in the myeloma cells at low nanomolar concentrations. Similar results could be observed in BM endothelial cells using higher concentrations, indicating the selectivity of JNJ-26481585 toward cancer cells. In a prophylactic and therapeutic setting, treatment with JNJ-26481585 resulted in an almost complete reduction of the tumor load and a significant decrease in angiogenesis. 5T2MM-bearing mice also developed a MM-related bone disease, characterized by increased osteoclast number, development of osteolytic lesions and a reduction in cancellous bone. Treatment of these mice with JNJ-264815 significantly reduced the development of bone disease. These data suggest that JNJ-26481585 has a potent anti-MM activity that can overcome the stimulatory effect of the BM microenvironment in vivo making this drug a promising new anti-MM agent.

Homing of the myeloma cell clone.

The presence of myeloma cells in the blood circulation. implicates that these cells must have the potential to extravasate and home to the bone marrow environment. Using the 5T2 MM mouse model, we could demonstrate that the restricted localization of myeloma cells in the bone marrow is the result of selective migration of myeloma cells in the bone marrow combined with a selective growth of the tumour cells in the bone marrow microenvironment. Moreover, we showed that 5T2 MM cells bind in vitro selectively to bone marrow-derived endothelial cells (EC) and not to lung-derived EC. In order to identify which chemotactic molecules mediate the transendothelial migration of myeloma cells, we examined the motility-inducing effect of different extracellular matrix proteins on myeloma cell lines. We found that laminin-1 a major component of the basement membrane, triggers the motility of both human myeloma cells and 5T2 MM cells, through the 67 kD laminin receptor. Because of the broad distribution of laminin in extracellular matrices throughout the body, it is clear that this molecule on itself can not be the only factor that determines the specificity of myeloma cell homing. In the 5T2 MM model we identified IGF-1 as a more specific bone marrow derived chemoattractant for myeloma cells. In addition we demonstrated that the marrow microenvironment can upregulate the expression of the IGF-1 receptor on 5T mouse myeloma cells. In the end phase of the disease, increasing numbers of myeloma cells are detectable in the peripheral blood and extramedullary tumour growth can occur. We found that the stroma-independent variant of the human MM5 myeloma cell line showed an increased in vitro motility as compared to the stroma-dependent variant. By representational difference analysis we demonstrated that the stroma-dependent MM5 cells show a downregulation of the motility-related protein (MRP-I CD9) which might reflect the involvement of this molecule in the regulation of myeloma cell extravasation.

Laminin-1-induced migration of multiple myeloma cells involves the high-affinity 67 kD laminin receptor.

The 67 kD laminin receptor (67LR) binds laminin-1 (LN), major component of the basement membrane, with high affinity. In this study, we demonstrated that human multiple myeloma cell lines (HMCL) and murine 5T2MM cells express 67LR. CD38(bright+) plasma cells in fresh multiple myeloma (MM) bone marrow (BM) samples showed weaker 67LR expression, but expression increased after direct exposure to a BM endothelial cell line (4LHBMEC). LN stimulated the in vitro migration of 3 HMCL (MM5.1, U266 and MMS.1), primary MM cells and the murine 5T2MM cells. 67LR has been shown to mediate the actions of LN through binding to CDPGYIGSR, a 9 amino acid sequence from the B1 chain of LN. MM cell migration was partially blocked by peptide 11, a synthetic nonapeptide derived from this amino sequence and also by a blocking antiserum against 67LR. Co-injection of peptide 11 with 5T2MM cells in a murine in vivo model of MM resulted in a decreased homing of 5T2MM cells to the BM compartment. In conclusion, LN acts as a chemoattractant for MM cells by interaction with 67LR. This interaction might be important during extravasation of circulating MM cells.

Chemokine receptor CCR2 is expressed by human multiple myeloma cells and mediates migration to bone marrow stromal cell-produced monocyte chemotactic proteins MCP-1, -2 and -3.

The restricted bone marrow (BM) localisation of multiple myeloma (MM) cells most likely results from a specific homing influenced by chemotactic factors, combined with the proper signals for growth and survival provided by the BM microenvironment. In analogy to the migration and homing of normal lymphocytes, one can hypothesise that the BM homing of MM cells is mediated by a multistep process, involving the concerted action of adhesion molecules and chemokines. In this study, we report that primary MM cells and myeloma derived cell lines (Karpas, LP-1 and MM5.1) express the chemokine receptor CCR2. In addition, we found that the monocyte chemotactic proteins (MCPs) MCP-1, -2 and -3, three chemokines acting as prominent ligands for CCR2, are produced by stromal cells, cultured from normal and MM BM samples. Conditioned medium (CM) from BM stromal cells, as well as MCP-1, -2 and -3, act as chemoattractants for human MM cells. Moreover, a blocking antibody against CCR2, as well as a combination of neutralizing antibodies against MCP-1, -2 and -3, significantly reduced the migration of human MM cells to BM stromal cell CM. The results obtained in this study indicate the involvement of CCR2 and the MCPs in the BM homing of human MM cells.

Selective initial in vivo homing pattern of 5T2 multiple myeloma cells in the C57BL/KalwRij mouse.

One of the main characteristics of multiple myeloma cells is their predominant localization in the bone marrow. It is, however, unclear whether this is due to a selective initial entry, or whether this entry is more random and other processes like survival and/or growth stimulation, only present in the medullar microenvironment, are unique. To investigate this, in vivo homing kinetics of murine 5T2MM cells shortly after injection were assessed in bone marrow, liver, spleen, lungs, heart, intestines, kidney and testis by tracing of radiolabelled cells, by immunostaining of isolated cells and by polymerase chain reaction analysis. We demonstrated the presence of 5T2MM cells in bone marrow, spleen and liver with all other organs being negative. Adhesion assays of 5T2MM cells to different types of endothelial cells demonstrated a selective adhesion of 5T2MM cells to bone marrow and liver and not to lung endothelial cells. We here demonstrate that the specific in vivo localization of the 5T2MM cells is a result of the combination of a selective entry/adhesion of the 5T2MM cells in the bone marrow, spleen and liver, and a selective survival and growth of these tumour cells in the bone marrow and spleen but not in the liver.