New drugs for myeloma

Interplay between proteasome inhibitors and NF-κB pathway in leukemia and lymphoma: a comprehensive review on challenges ahead of proteasome inhibitors

The current scientific literature has extensively explored the potential role of proteasome inhibitors (PIs) in the NF-κB pathway of leukemia and lymphoma. The ubiquitin-proteasome system (UPS) is a critical component in regulating protein degradation in eukaryotic cells. PIs, such as BTZ, are used to target the 26S proteasome in hematologic malignancies, resulting in the prevention of the degradation of tumor suppressor proteins, the activation of intrinsic mitochondrial-dependent cell death, and the inhibition of the NF-κB signaling pathway. NF-κB is a transcription factor that plays a critical role in the regulation of apoptosis, cell proliferation, differentiation, inflammation, angiogenesis, and tumor migration. Despite the successful use of PIs in various hematologic malignancies, there are limitations such as resistant to these inhibitors. Some reports suggest that PIs can induce NF-κB activation, which increases the survival of malignant cells. This article discusses the various aspects of PIs' effects on the NF-κB pathway and their limitations. Video Abstract.

Advances in the Management of Neuroblastoma

Neuroblastoma is a malignant tumor of neuroblasts, immature nerve cells found in several areas of the body. It usually affects children under age of 5. As usual, the tumor has ability to grow rapidly and to expand vastly which ultimately leads to death. Mostly, management decisions can be drawn by the prediction of the stage of the disease as well as age at the time of its diagnosis. There are four main stages of neuroblastoma, and treatment is according to the low and high risk of the disease. Several cytotoxic agents along with other therapies (antibody therapy, gene therapy, and even immunological therapies, antiangiogenic therapy, etc.) are used. Immunotherapy also has an important treatment option used nowadays for neuroblastoma. The discovery of major neuroblastoma-predisposition gene anaplastic lymphoma kinase cause somatic transformation or gene strengthening in diagnosed neuroblastoma. Promising new antiangiogenic strategies have also been introduced for the treatment of neuroblastoma with multiple mylomas. To manage numerous myelomas and cancers, including neuroblastoma, bone marrow transplantation and peripheral blood stem cell transplantation may be used.

Targeting metabolism: A potential strategy for hematological cancer therapy

Most hematological cancer-related relapses and deaths are caused by metastasis; thus, the importance of this process as a target of therapy should be considered. Hematological cancer is a type of cancer in which metabolism plays an essential role in progression. Therefore, we are required to block fundamental metastatic processes and develop specific preclinical and clinical strategies against those biomarkers involved in the metabolic regulation of hematological cancer cells, which do not rely on primary tumor responses. To understand progress in this field, we provide a summary of recent developments in the understanding of metabolism in hematological cancer and a general understanding of biomarkers currently used and under investigation for clinical and preclinical applications involving drug development. The signaling pathways involved in cancer cell metabolism are highlighted and shed light on how we could identify novel biomarkers involved in cancer development and treatment. This review provides new insights into biomolecular carriers that could be targeted as anticancer biomarkers.

Surgical Management of Multiple Myeloma With Symptomatic Involvement of the Spine

INTRODUCTION

Multiple myeloma (MM) is the most frequent primary malignancy of the spine. We aimed to investigate the clinical presentation, surgical indications and outcomes, complications, survival, and its influencing factors in surgically treated MM patients with symptomatic involvement of the spine (SIS).

METHODS

Retrospective analysis of prospectively collected data. Out of 350 MM patients treated at our institution over a period of 12 years (2006-2018), we identified 24 patients who were surgically treated for SIS. We collected data on demographics, clinical presentation, comorbidities, surgical indications, and outcomes and investigated the factors predisposing to postoperative complications and survival.

RESULTS

The median follow-up duration was 85 months; median overall survival (OS) was 50 months. Clinical presentation at admission included pain (88%), sensory and/or motor deficit (67%), and bowel/bladder dysfunction (25%). Symptomatic pathological fractures were seen in 33%. Predominant surgical indications were rapid neurological deterioration with or without spinal cord compression (SCC), followed by mechanical instability. The majority of our patients benefited from surgery in terms of pain reduction in the short term as well as in the long term. There were 21% patients with surgical-related complications (<3 months). Surgical site infections occurred in 17%, without any obvious factors predisposing to infective complications. Neurological deterioration during hospital stay, especially in the presence of motor deficit and/or bowel/bladder dysfunction, significantly reduced OS.

CONCLUSIONS

Sudden-onset neurological deterioration was the predominant factor leading to surgery. We achieved good short- and long-term pain reduction. Surgery is a valuable option for MM patients with SIS who present with rapid neurological deterioration with or without SCC and/or mechanical instability.

Plasma Cell Leukemia - Facts and Controversies: More Questions than Answers?

Plasma cell leukemia (PCL) is an aggressive hematological malignancy characterized by an uncontrolled clonal proliferation of plasma cells (PCs) in the bone marrow and peripheral blood. PCL has been defined by an absolute number of circulating PCs exceeding 2.0 × 10⁹/L and/or >20% PCs in the total leucocyte count. It is classified as primary PCL, which develops de novo, and secondary PCL, occurring at the late and advanced stages of multiple myeloma (MM). Primary and secondary PCL are clinically and biologically two distinct entities. After the diagnosis, treatment should be immediate and should include a proteasome inhibitor and immunomodulator-based combination regimens as induction, followed by stem cell transplantation (SCT) in transplant-eligible individuals who have cleared the peripheral blood of circulating PCs. Due to the rarity of the condition, there have been very few clinical trials. Furthermore, virtually all of the myeloma trials exclude patients with active PCL. The evaluation of response has been defined by the International Myeloma Working Group and consists of both acute leukemia and MM criteria. With conventional chemotherapy, the prognosis of primary PCL has been ominous, with reported overall survival (OS) ranging from 6.8 to 12.6 months. The use of novel agents and autologous SCT appears to be associated with deeper response and an improved survival, although it still remains low. The PCL prognostic index provides a simple score to risk-stratify PCL. The prognosis of secondary PCL is extremely poor, with OS of only 1 month.

Population Pharmacokinetics and Exposure Response Analysis of Pomalidomide in Subjects With Relapsed or Refractory Multiple Myeloma From the Novel Combination Treatment of Pomalidomide, Bortezomib, and Low-Dose Dexamethasone

Multiple myeloma is an incurable progressive neoplastic disease that accounts for 10% of all hematologic malignancies. Even though significant progress has been made in the treatment of newly diagnosed multiple myeloma, the disease follows a relapsing course in the majority of patients, and there is a need for more effective therapeutic options for the treatment of relapsed or refractory multiple myeloma. CC-4047-MM-005 and CC-4047-MM-007 were phase 1 and 3 studies to evaluate the novel combination of pomalidomide, bortezomib, and low-dose dexamethasone for the treatment of patients with relapsed or refractory multiple myeloma who have already received lenalidomide-based treatments early. This analysis was performed to characterize the population pharmacokinetics (PK) of pomalidomide from the combination treatment and to examine exposure-response relationships. Our analysis showed that pomalidomide concentration-time profiles from the combination treatment were adequately described with a 1-compartment PK model, with first-order absorption and elimination and pomalidomide exhibiting linear and time-invariant PK with moderate variability from the combination treatment. Except for the body surface area, none of the tested covariates had an effect on pomalidomide PK. Although body surface area was identified as a statistically significant covariate of pomalidomide PK, the impact was not deemed clinically relevant. A flat exposure-response curve was observed, consistent with a near-saturated drug effect at the tested exposure range suggesting an appropriately recommended clinical dose of 4 mg of pomalidomide for the combination treatment. Finally, pomalidomide exposure was not associated with higher probabilities of dose interruption during cycle 1 or dose reduction during the treatment period.

A randomized phase II, open-label and multicenter study of combination regimens of bortezomib at two doses by subcutaneous injection for newly diagnosed multiple myeloma patients

PURPOSE

Combinations of bortezomib (Velcade), cyclophosphamide and dexamethasone have shown significant efficacy and safety for patients of newly diagnosed multiple myeloma (NDMM). In this study, we compared the efficacy and safety of modified VCD regimens with novel changes in bortezomib dose and schedule for NDMM.

METHODS

Eighty-five NDMM patients from multiple centers were randomly assigned to a high-dose (1.6 mg/m²) (group A) or a low-dose (1.3 mg/m²) (group B) bortezomib, administrated on days 1, 6, 11, and 16 subcutaneously in a 4-week cycle for nine cycles, combined with 40 mg dexamethasone on bortezomib days and cyclophosphamide 300 mg/m² on days 1-3 intravenously.

RESULTS

After four cycles, complete response (CR) or better in group A (43.6%) was higher than that in group B (12.8%) (P = 0.002). During induction, for patients with R-ISS stage III, the CR or better rate in group A was superior to that in group B (P = 0.01). Of patients < 65, the CR or better rate of group A was superior to that of group B (P = 0.004). Rapid onset of CR occurred in group A (P < 0.01). Meanwhile, rate of 3-4 diarrhea was higher in group A (P = 0.03), which caused higher rate of dose reduction for patients ≥ 65 (P = 0.041). No significant difference between the two groups in PFS and OS.

CONCLUSIONS

The studied high-dose VCD as induction regimen had an improved CR rate, especially in patients < 65 or with R-ISS stage III, and is feasible for young and high-risk patients. Trial registration ClinicalTrials.gov: NCT02086942.

Clinical, electrophysiological, and cutaneous innervation changes in patients with bortezomib-induced peripheral neuropathy reveal insight into mechanisms of neuropathic pain

Bortezomib is a mainstay of therapy for multiple myeloma, frequently complicated by painful neuropathy. The objective of this study was to describe clinical, electrophysiological, and pathological changes of bortezomib-induced peripheral neuropathy (BiPN) in detail and to correlate pathological changes with pain descriptors. Clinical data, nerve conduction studies, and lower leg skin biopsies were collected from 22 BiPN patients. Skin sections were immunostained using anti-protein gene product 9.5 (PGP9.5) and calcitonin gene-related peptide (CGRP) antibodies. Cumulative bortezomib dose and clinical assessment scales indicated light-moderate sensory neuropathy. Pain intensity >4 (numerical rating scale) was present in 77% of the patients. Median pain intensity and overall McGill Pain Questionnaire (MPQ) sum scores indicated moderate to severe neuropathic pain. Sural nerve sensory nerve action potentials were abnormal in 86%, while intraepidermal nerve fiber densities of PGP9.5 and CGRP were not significantly different from healthy controls. However, subepidermal nerve fiber density (SENFD) of PGP9.5 was significantly decreased and the axonal swelling ratio, a predictor of neuropathy, and upper dermis nerve fiber density (UDNFD) of PGP9.5, presumably representing sprouting of parasympathetic fibers, were significantly increased in BiPN patients. Finally, significant correlations between UDNFD of PGP9.5 versus the evaluative Pain Rating Index (PRI) and number of words count (NWC) of the MPQ, and significant inverse correlations between SENFD/UDNFD of CGRP versus the sensory-discriminative MPQ PRI/NWC were found. BiPN is a sensory neuropathy, in which neuropathic pain is the most striking clinical finding. Bortezomib-induced neuropathic pain may be driven by sprouting of parasympathetic fibers in the upper dermis and impaired regeneration of CGRP fibers in the subepidermal layer.

EXPRESSION OF CANCER-TESTIS GENES PRAME, NY-ESO1, GAGE1, MAGE A3, MAGE A6, MAGE A12, SSX1, SLLP1, PASD1 IN PATIENTS WITH MULTIPLE MYELOMA, THEIR INFLUENCE ON OVERALL SURVIVAL AND RELAPSE RATE

Objective:to study the prognostic significance of the expression of cancer-testis (CT) genes PRAME, NY-ESO1, GAGE1, MAGE A3, MAGE A6, MAGE A12, SSX1, SLLP1, PASD1 in patients with multiple myeloma (MM) and their influence on overall survival and relapse rate. To determine their effect on suсh clinical parameters as levels of lactate dehydrogenase, leucocytes, hemoglobin, calcium, albumen, creatinine, beta-2-microglobulin.

Materials and methods.Real-time polymerase chain reaction was performed on complementary DNA obtained from bone marrow of 77 patients with MM. The statistical analysis was performed using the Statistica 10.0 software package. To estimate prognostic values of the CT gene expression data were analyzed by the Kaplan – Meier method.

Results.The study was conducted to determine the level of expression of CT genes PRAME, NY-ESO1, GAGE1, MAGE A3, MAGE A6, MAGE A12, SSX1, SLLP1, PASD1 in a group of patients with MM. The group included primary and receiving cancer treatment in MM patients. According to the log-rank criterion expression of any of the CT genes PRAME, NY-ESO1, GAGE1, MAGE A3, MAGE A6, MAGE A12, SSX1, SLLP1, PASD1 exerts a significant influence on overall survival and progression-free survival/relapse. It was also determined that providing expression of some CT genes, the levels of creatinine, calcium, beta-2-microglobulin were much higher to compare with patients without expression.

DANFIN functions as an inhibitor of transcription factor NF-κB and potentiates the antitumor effect of bortezomib in multiple myeloma

Nuclear factor-κB (NF-κB) proteins are transcription factors that play key roles in regulating most immune responses and cell death. Constitutively active NF-κB has been shown to exhibit chemoresistance by inducing anti-apoptosis in tumor cells. Multiple myeloma is known as a constitutive NF-κB activating disease, and the proteasome inhibitor bortezomib is used to treat multiple myeloma and mantle cell lymphoma. We demonstrate here that DANFIN (N,N'-bis-(2,4-dimethyl-phenyl)-ethane-1,2-diamine) functions as an inhibitor of the p65 family proteins and induces chemosensitization to bortezomib in multiple myeloma. DANFIN was found to be an inhibitor of interactions between p65 and IκBα without the inhibition of the DNA binding activity of the p65 protein. In addition, DANFIN affected the IκBα binding region in Rel Homology Domain (RHD) and suppressed the nuclear translocalization of the p65 protein in cells. Furthermore, in multiple myeloma cells, DANFIN suppressed the expression level of NF-κB target genes and induced apoptosis. The combination therapy of DANFIN with bortezomib dramatically enhanced the apoptosis of multiple myeloma cells and indicated a remarkable anti-tumor effect in a multiple-myeloma xenograft mouse model.

Phase II study of bortezomib, cyclophosphamide and dexamethasone as induction therapy in multiple myeloma: DSMM XI trial

We assessed the safety and efficacy of bortezomib, cyclophosphamide and dexamethasone (VCD) induction therapy in previously untreated multiple myeloma patients. A total of 414 patients received three 21-day cycles of VCD prior to autologous stem-cell transplantation (ASCT). Most common grade ≥3 adverse events were leucopenia (31·4%) and thrombocytopenia (6·8%). The overall response rate (ORR) by investigator-based assessment was 85·4%. Most patients (74%) underwent successful central laboratory-based molecular cytogenetic analysis. No clinically relevant differences in ORR post-induction were seen between patients with or without high-risk cytogenetic abnormalities (86·2% vs. 84·3%). Further follow-up data are available for 113 patients receiving ASCT who were included in a prospective consolidation trial (median follow-up, 55·5 months); median progression-free survival (PFS) was 35·3 months and median overall survival (OS) was not reached. In patients with high-risk versus standard-risk cytogenetics, median PFS was 19·9 vs. 43·6 months (P < 0·0001), and median OS was 54·7 months versus not reached (P = 0·0022). VCD is an effective and tolerable induction regimen; results suggest that VCD induces high response rates independently of cytogenetic risk status, but after long-term follow-up, cytogenetic high risk is associated with markedly reduced PFS and OS post-ASCT.

Multiple myeloma in Niger Delta, Nigeria: complications and the outcome of palliative interventions

Background

Multiple myeloma (MM) is one of the hematological malignancies that require palliative care. This is because of the life-threatening nature and the suffering associated with the illness. The aim of this study is to bring to the fore the complications experienced by people living with MM in the Niger-Delta region of Nigeria and the outcome of various palliative interventions.

Methods

This was a 10-year multi-center retrospective study of 26 patients diagnosed and managed in three major centers in the Niger-Delta region of Nigeria from January 2003 to December 2012. Information on the clinical, laboratory, radiological data, and palliative treatment was obtained at presentation and subsequently at intervals of 3 months until the patient was lost to follow-up.

Result

The mean duration from onset of symptoms to diagnosis was 13.12 months (95% CI, 6.65–19.58). A total of 16 (61.5%), eight (30.8%), and two subjects (7.7%) presented in Durie–Salmon (DS) stages III, II, and I, respectively. The complications presented by patients at diagnoses included bone pain (84.6%), anemia (61.5%), nephropathy (23.1%), and hemiplegia (35%). All the patients received analgesics, while 50.0% received blood transfusion, 56.7% had surgery performed, 19% had hemodialysis, and 3.8% received radiotherapy. A total of 10 (38%) patients benefited from bisphosphonates (BPs). A total of 57.6% of patients were on melphalan–prednisone (MP) double regimen, while 19% and 8% patients were on MP–thalidomide and MP–bortezomib triple regimens, respectively. A total of 3.8% of patients at DS stage IIIB disease had autologous stem-cell transplantation (ASCT). Only 7.6% of the myeloma patients survived up to 5 years post diagnosis. The overall mean survival interval was 39.7 months (95% CI, 32.1–47.2).

Conclusion

Late diagnosis and inadequate palliative care account for major complications encountered by MM patients in the Niger-Delta region of Nigeria. This could be responsible for the poor prognostic outcome and low survival interval of MM individuals in this region. There is, therefore, a need to improve the quality of palliative care received by myeloma patients in this region. This is achievable via provision of relevant and affordable health care facilities for diagnosis and treatment of the disease.

CG13250, a novel bromodomain inhibitor, suppresses proliferation of multiple myeloma cells in an orthotopic mouse model

Multiple myeloma (MM) is characterized by the clonal proliferation of neoplastic plasma cells. Despite a stream of new molecular targets based on better understanding of the disease, MM remains incurable. Epigenomic abnormalities contribute to the pathogenesis of MM. bromodomain 4 (BRD4), a member of the bromodomain and extraterminal (BET) family, binds to acetylated histones during M/G1 transition in the cell cycle promoting progression to S phase. In this study, we investigated the effects of a novel BET inhibitor CG13250 on MM cells. CG13250 inhibited ligand binding to BRD4 in a dose-dependent manner and with an IC₅₀ value of 1.1 μM. It inhibited MM proliferation in a dose-dependent manner and arrested cells in G1, resulting in the induction of apoptosis through caspase activation. CG13250 inhibited the binding of BRD4 to c-MYC promoter regions suppressing the transcription of the c-MYC gene. Administered in vivo, CG13250 significantly prolonged survival of an orthotopic MM-bearing mice. In conclusion, CG13250 is a novel bromodomain inhibitor that is a promising molecular targeting agent against MM.

Cyclophilin A as a downstream effector of PI3K/Akt signalling pathway in multiple myeloma cells

Cyclophilin A (Cyp A), a member of the peptidyl-prolyl isomerase (PPI) family, may function as a molecular signalling switch. Comparative proteomic studies have identified Cyp A as a potential downstream target of protein kinase B (Akt). This study confirmed that Cyp A is a downstream effector of the phosphatidylinositide 3-kinase (PI3K)/Akt signalling pathway. Cyp A was highly phosphorylated in response to interleukin-6 treatment, which was consistent with the accumulation of phosphorylated Akt, suggesting that Cyp A is a phosphorylation target of Akt and downstream effector of the PI3K/Akt pathway. Cyclosporine A (CsA), a PPI inhibitor, inhibited the growth of multiple myeloma (MM) U266 cells. Moreover, CsA treatment inhibited the activation of the signal transducer and activator of transcription 3 (STAT3) in MM U266 cells. Several Cyp A mutants were generated. Mutants with mutated AKT phosphorylation sites increased the G1 phase arrest in MM U266 cells. The other mutants that mimicked the phosphorylated state of Cyp A decreased the percentage of G1 phase. These results demonstrated that the states of phosphorylation of Cyp A by Akt can influence the progress of the cell cycle in MM U266 cells and that this effect is probably mediated through the Janus-activated kinase 2/STAT3 signalling pathway.

Real-world treatment patterns, comorbidities, and disease-related complications in patients with multiple myeloma in the United States

OBJECTIVES

To describe multiple myeloma (MM) treatment patterns and comorbidities over time in the US.

RESEARCH DESIGN AND METHODS

Study patients were newly diagnosed with MM (ICD-9-CM 203.0x) between 1 July 2006 and 31 March 2014 and had ≥6 months of data prior to the initial MM diagnosis in MarketScan Research Databases. Patients were followed until inpatient death or the end of data. First-line, second-line, and third-line treatment regimens were identified following diagnosis and were described over time based upon the start date of the first line of therapy (2006-2007, 2008-2014, 2013-2014). Comorbid conditions and disease-related complications were examined during the 6 months prior to the line of therapy start dates.

RESULTS

A total of 24,507 MM patients were examined (mean age: 65.2 years, 54.1% male, mean follow-up: 23 months, 16.2% transplant). Across all lines of therapy, the proportion of patients on thalidomide-based regimens decreased over time. In the first line, bortezomib-based regimens became more common from 2006-2007 to 2008-2014 (2006-2007: 17.0%, 2008-2014: 44.3%, 2013-2014: 49.4%). In the second line, lenalidomide- and bortezomib-based regimens were the most common (2013-2014: lenalidomide: 28.9%, bortezomib: 26.2%). The combination regimen of lenalidomide + bortezomib became more common in the first and second lines. In the third line, carfilzomib- and/or pomalidomide-based regimens were 37.0% in 2013-2014. Skeletal-related events, hypertension, anemia, and chronic kidney disease were the most prevalent comorbidities and disease-related complications. During the 6 months prior to each line of therapy, the prevalence of the majority of the comorbidities and complications increased as patients progressed to higher lines of therapy.

CONCLUSIONS

MM treatment patterns have been dynamic over time. Comorbid conditions and myeloma-related complications increase as patients progress and may worsen MM patients' prognoses over time. Combination regimens such as lenalidomide + bortezomib are more widely used as first- and second-line therapy. Newly approved agents (carfilzomib, pomalidomide) are the prevailing treatments in the third line and are under further investigation for earlier lines of therapy.

Aberrant nuclear factor-kappa B activity in acute myeloid leukemia: from molecular pathogenesis to therapeutic target

The overall survival of patients with acute myeloid leukemia (AML) has not been improved significantly over the last decade. Molecularly targeted agents hold promise to change the therapeutic landscape in AML. The nuclear factor kappa B (NF-κB) controls a plethora of biological process through switching on and off its long list of target genes. In AML, constitutive NF-κB has been detected in 40% of cases and its aberrant activity enable leukemia cells to evade apoptosis and stimulate proliferation. These facts suggest that NF-κB signaling pathway plays a fundamental role in the development of AML and it represents an attractive target for the intervention of AML. This review summarizes our current knowledge of NF-κB signaling transduction including canonical and non-canonical NF-κB pathways. Then we specifically highlight what factors contribute to the aberrant activation of NF-κB activity in AML, followed by an overview of 8 important clinical trials of the first FDA approved proteasome inhibitor, Bortezomib (Velcade), which is a NF-κB inhibitor too, in combination with other therapeutic agents in patients with AML. Finally, this review discusses the future directions of NF-κB inhibitor in treatment of AML, especially in targeting leukemia stem cells (LSCs).

Safety and tolerability of ixazomib, an oral proteasome inhibitor, in combination with lenalidomide and dexamethasone in patients with previously untreated multiple myeloma: an open-label phase 1/2 study

BACKGROUND

The combination of bortezomib, lenalidomide, and dexamethasone is a highly effective therapy for newly diagnosed multiple myeloma. Ixazomib is an investigational, oral, proteasome inhibitor with promising anti-myeloma effects and low rates of peripheral neuropathy. In a phase 1/2 trial we aimed to assess the safety, tolerability, and activity of ixazomib in combination with lenalidomide and dexamethasone in newly diagnosed multiple myeloma.

METHODS

We enrolled patients newly diagnosed with multiple myeloma aged 18 years or older with measurable disease, Eastern Cooperative Oncology Group performance status 0-2, and no grade 2 or higher peripheral neuropathy, and treated them with oral ixazomib (days 1, 8, 15) plus lenalidomide 25 mg (days 1-21) and dexamethasone 40 mg (days 1, 8, 15, 22) for up to 12 28-day cycles, followed by maintenance therapy with ixazomib alone. In phase 1, we gave patients escalating doses of ixazomib (1·68-3·95 mg/m(2)) to establish the recommended dose for phase 2. The primary endpoints were maximum tolerated dose for phase 1, and the rate of very good partial response or better for phase 2. Safety analyses were done in all patients who received at least one dose of study drug; efficacy analyses were done in all patients who received at least one dose of study drug at the phase 2 dose, had measurable disease at baseline, and had at least one post-baseline response assessment. This study is registered at ClinicalTrials.gov, number NCT01217957.

FINDINGS

Between Nov 22, 2010, and Feb 28, 2012, we enrolled 65 patients (15 to phase 1 and 50 to phase 2). Four dose-limiting toxic events were noted in phase 1: one at a dose of ixazomib of 2·97 mg/m(2) and three at 3·95 mg/m(2). The maximum tolerated dose of ixazomib was established as 2·97 mg/m(2) and the recommended phase 2 dose was 2·23 mg/m(2), which was converted to a 4·0 mg fixed dose based on population pharmacokinetic results. Grade 3 or higher adverse events related to any drug were reported in 41 (63%) patients, including skin and subcutaneous tissue disorders (11 patients, 17%), neutropenia (eight patients, 12%), and thrombocytopenia (five patients, 8%); drug-related peripheral neuropathy of grade 3 or higher occurred in four (6%) patients. Five patients discontinued because of adverse events. In 64 response-evaluable patients, 37 (58%, 95% CI 45-70) had a very good partial response or better.

INTERPRETATION

The all-oral combination of weekly ixazomib plus lenalidomide and dexamethasone was generally well tolerated and appeared active in newly diagnosed multiple myeloma. These results support the phase 3 trial development of this combination for multiple myeloma.

FUNDING

Millennium Pharmaceuticals, a wholly owned subsidiary of Takeda Pharmaceutical International Company.

Optimizing the treatment of patients with multiple myeloma and renal impairment

Renal impairment is a common complication of multiple myeloma. It is found in about 20% to 25% of patients at diagnosis and in ≤ 50% at some point during the disease course. The presence of renal insufficiency diminishes patients' quality of life and has been associated with increased mortality, although the outcomes of patients after successful induction therapy have been comparable to those with normal renal function. Therefore, the treatment of patients with multiple myeloma and renal impairment is a major challenge and should aim to achieve remission in a large proportion of patients. New drugs introduced to treat multiple myeloma during the past decade have an established place in the treatment of patients with renal failure. Bortezomib appears to be most beneficial in this setting and, combined with other drugs, provides a chance for rapid remission and related improvement of renal function. Immunomodulatory drugs such as thalidomide and lenalidomide have also been used successfully in patients with renal insufficiency, although for the latter drug appropriate dose adjustments are necessary. The presence of renal failure is not a contraindication to autologous bone marrow transplantation in patients eligible for this procedure. Among the classic cytotoxic agents, bendamustine, in particular, should be considered for patients with renal insufficiency. Appropriate supportive care is also extremely important in the treatment of patients with multiple myeloma and renal failure. It can include plasmapheresis and removal of free light chains with high cut-off hemodialysis, adapted dosages of bisphosphonates, and avoidance of drugs and conditions that can impair renal function.

Treatment of transplant-eligible patients with multiple myeloma in 2014

Induction regimens containing a proteasome inhibitor and/or immunomodulatory agent with dexamethasone result in rapid disease control before autologous stem cell transplantation (ASCT). ASCT followed by consolidation and/or maintenance further improves depth of response following effective induction. Overall survival of transplant-eligible patients has been extended with modern therapeutic strategies. The optimal timing of ASCT and methods to prevent relapse following ASCT are under active investigation. Different patient populations may benefit differentially from currently available treatments.

Pomalidomide alone or in combination with low-dose dexamethasone in relapsed and refractory multiple myeloma: a randomized phase 2 study

This multicenter, open-label, randomized phase 2 study assessed the efficacy and safety of pomalidomide (POM) with/without low-dose dexamethasone (LoDEX) in patients with relapsed/refractory multiple myeloma (RRMM). Patients who had received ≥2 prior therapies (including lenalidomide [LEN] and bortezomib [BORT]) and had progressed within 60 days of their last therapy were randomized to POM (4 mg/day on days 1-21 of each 28-day cycle) with/without LoDEX (40 mg/week). The primary end point was progression-free survival (PFS). In total, 221 patients (median 5 prior therapies, range 1-13) received POM+LoDEX (n = 113) or POM (n = 108). With a median follow-up of 14.2 months, median PFS was 4.2 and 2.7 months (hazard ratio = 0.68, P = .003), overall response rates (ORRs) were 33% and 18% (P = .013), median response duration was 8.3 and 10.7 months, and median overall survival (OS) was 16.5 and 13.6 months, respectively. Refractoriness to LEN, or resistance to both LEN and BORT, did not affect outcomes with POM+LoDEX (median PFS 3.8 months for both; ORRs 30% and 31%; and median OS 16 and 13.4 months). Grade 3-4 neutropenia occurred in 41% (POM+LoDEX) and 48% (POM); no grade 3-4 peripheral neuropathy was reported. POM+LoDEX was effective and generally well tolerated and provides an important new treatment option for RRMM patients who have received multiple prior therapies. This trial was registered at www.clinicaltrials.gov as #NCT00833833.

Phase Ib Study of Panobinostat and Bortezomib in Relapsed or Relapsed and Refractory Multiple Myeloma

Purpose

Despite advancements, prognosis for patients with relapsed/refractory multiple myeloma (MM) is poor, and novel therapies are needed. Panobinostat is a potent deacetylase inhibitor that elicits synergistic effects on MM cells in combination with bortezomib. This phase Ib study sought to determine the maximum-tolerated dose (MTD) of panobinostat plus bortezomib in patients with relapsed or relapsed and refractory MM.

Patients and Methods

In the dose-escalation phase (n = 47), panobinostat was administered orally thrice weekly every week in combination with bortezomib (21-day cycles). After MTD determination, patients were evaluated in an expansion phase (n = 15) that incorporated a 1-week treatment holiday of panobinostat, with dexamethasone added in cycle 2. Additional assessments included safety, pharmacokinetics, and efficacy per International Myeloma Working Group criteria.

Results

The MTD was established at panobinostat 20 mg plus bortezomib 1.3 mg/m2. Grade 3 or 4 adverse events (AEs) included thrombocytopenia (85.1%), neutropenia (63.8%), and asthenia (29.8%) in the escalation phase, and thrombocytopenia (66.7%), neutropenia (46.7%), and fatigue (20.0%) in the expansion phase. At MTD in the escalation phase, eight patients (47.1%) discontinued therapy as a result of AEs, whereas five patients (33.3%) discontinued treatment in the expansion phase. Expansion phase patients demonstrated greater median treatment duration. Overall response rate (ORR) was 73.3% in the expansion phase and 52.9% at the escalation phase MTD. Among bortezomib-refractory patients, the ORR was 26.3%, and 42.1% of patients had ≥ minimal response.

Conclusion

The MTD of panobinostat plus bortezomib was determined and demonstrated activity in patients with relapsed or relapsed/refractory MM, including bortezomib-refractory patients. A phase II/III clinical trial program (Panobinostat or Placebo With Bortezomib and Dexamethasone in Patients With Relapsed Multiple Myeloma [PANORAMA]) has been initiated.

PANORAMA 2: panobinostat in combination with bortezomib and dexamethasone in patients with relapsed and bortezomib-refractory myeloma

Panobinostat + bortezomib + dexamethasone recaptures responses in heavily pretreated, bortezomib-refractory multiple myeloma patients.

Clinical challenges: Myeloma and concomitant type 2 diabetes

Multiple myeloma is a malignant plasma cell disorder that accounts for approximately 10% of all hematological cancers. It is characterized by accumulation of clonal plasma cells, predominantly in the bone marrow. The prevalence of type 2 diabetes is increasing; therefore, it is expected that there will be an increase in the diagnosis of multiple myeloma with concomitant diabetes mellitus. The treatment of multiple myeloma and diabetes mellitus is multifaceted. The coexistence of the two conditions in a patient forms a major challenge for physicians.

"Real-world" data on the efficacy and safety of lenalidomide and dexamethasone in patients with relapsed/refractory multiple myeloma who were treated according to the standard clinical practice: a study of the Greek Myeloma Study Group

Lenalidomide and dexamethasone (RD) is a standard of care for relapsed/refractory multiple myeloma (RRMM), but there is limited published data on its efficacy and safety in the "real world" (RW), according to the International Society of Pharmacoeconomics and Outcomes Research definition. We studied 212 RRMM patients who received RD in RW. Objective response (≥PR (partial response)) rate was 77.4 % (complete response (CR), 20.2 %). Median time to first and best response was 2 and 5 months, respectively. Median time to CR when RD was given as 2nd or >2(nd)-line treatment at 4 and 11 months, respectively. Quality of response was independent of previous lines of therapies or previous exposure to thalidomide or bortezomib. Median duration of response was 34.4 months, and it was higher in patients who received RD until progression (not reached versus 19 months, p < 0.001). Improvement of humoral immunity occurred in 60 % of responders (p < 0.001) and in the majority of patients who achieved stable disease. Adverse events were reported in 68.9 % of patients (myelosuppression in 49.4 %) and 12.7 % of patients needed hospitalization. Peripheral neuropathy was observed only in 2.5 % of patients and deep vein thrombosis in 5.7 %. Dose reductions were needed in 31 % of patients and permanent discontinuation in 38.9 %. Median time to treatment discontinuation was 16.8 months. Performance status (PS) and initial lenalidomide dose predicted for treatment discontinuation. Extra-medullary relapses occurred in 3.8 % of patients. Our study confirms that RD is effective and safe in RRMM in the RW; it produces durable responses especially in patients who continue on treatment till progression and improves humoral immunity even in patients with stable disease.

Histone deacetylase inhibitors in multiple myeloma: rationale and evidence for their use in combination therapy

Multiple myeloma (MM) arises from abnormal proliferation and survival (ie, a high proliferative index and a low apoptotic index) of mature immunoglobulin-producing plasma cells in the bone marrow. Development of novel therapeutic options, such as proteasome inhibitors and immunomodulatory agents (IMiDs), has improved treatment outcomes. However, patients often develop relapsed and refractory MM, thus requiring alternative treatment approaches. Histone acetyltransferases and histone deacetylases (HDACs) control the acetylation status of proteins and affect a broad array of physiologic processes (eg, cell cycle, apoptosis, and protein folding) involved in cell growth and survival. The discovery that HDACs might have a role in various hematologic malignancies, including MM, has led to the development of HDAC inhibitors as potential antitumor agents. Preclinical evidence from studies of HDAC inhibitors in combination with proteasome inhibitors (eg, bortezomib and carfilzomib), other antimyeloma agents, including IMiDs (eg, lenalidomide), and cytotoxic agents (eg, melphalan, pegylated liposomal doxorubicin), provides a strong scientific rationale for the evaluation of these regimens. Results from early stage clinical trials further support the use of HDAC inhibitors as a therapeutic option for MM, in combination with current and emerging antimyeloma agents. In this review, we examine the role of protein acetylation that underlies the antimyeloma effects of HDAC inhibitors, discuss the preclinical rationale for the use of HDAC inhibitors in combination with other antimyeloma agents, and provide an overview of the current clinical evidence supporting the use of HDAC inhibitors as a therapeutic option in MM.

The interaction of bortezomib with multidrug transporters: implications for therapeutic applications in advanced multiple myeloma and other neoplasias

PURPOSE

Bortezomib is an important agent in multiple myeloma treatment, but resistance in cell lines and patients has been described. The main mechanisms of resistance described in cancer fall into one of two categories, pharmacokinetic resistance (PK), e.g. over expression of drug efflux pumps and pharmacodynamic resistance, e.g. apoptosis resistance or altered survival pathways, where the agent reaches an appropriate concentration, but this fails to propagate an appropriate cell death response. Of the known pump mechanisms, P-glycoprotein (P-gp) is the best studied and considered to be the most important in contributing to general PK drug resistance. Resistance to bortezomib is multifactorial and there are conflicting indications that cellular overexpression of P-gp may contribute to resistance agent. Hence, better characterization of the interactions of this drug with classical resistance mechanisms should identify improved treatment applications.

METHODS

Cell lines with different P-gp expression levels were used to determine the relationship between bortezomib and P-gp. Coculture system with stromal cells was used to determine the effect of the local microenvironment on the bortezomib-elacridar combination. To further assess P-gp function, intracellular accumulation of P-gp probe rhodamine-123 was utilised.

RESULTS

In the present study, we show that bortezomib is a substrate for P-gp, but not for the other drug efflux transporters. Bortezomib activity is affected by P-gp expression and conversely, the expression of P-gp affect bortezomib's ability to act as a P-gp substrate. The local microenvironment did not alter the cellular response to bortezomib. We also demonstrate that bortezomib directly affects the expression and function of P-gp.

CONCLUSIONS

Our findings strongly support a role for P-gp in bortezomib resistance and, therefore, suggest that combination of a P-gp inhibitor and bortezomib in P-gp positive myeloma would be a reasonable treatment combination to extend efficacy of this important drug.

Early response to bortezomib combined chemotherapy can help predict survival in patients with multiple myeloma who are ineligible for stem cell transplantation

Novel agents to treat multiple myeloma (MM) have increased complete respone (CR) rates compared with conventional chemotherapy, and the quality of the response to treatment has been correlated with survival. The purpose of our study was to show how of early response to bortezomib combined chemotherapy influences survival in patients with newly diagnosed MM who are ineligible for stem cell transplantation. We assessed patient responses to at least four cycles of bortezomib using the International Myeloma Working Group response criteria. The endpoints were comparisons of progression free survival (PFS) and overall survival (OS) between early good response group (A group) and poor response group (B group). We retrospectively analyzed data from 129 patients registered by the Korean Multiple Myeloma Working Party, a nationwide registration of MM patients. The 3 yr PFS for the A and B groups was 55.6% and 18.4%, respectively (P < 0.001). The 3 yr OS for the A and B groups was 65.3% and 52.9%, respectively (P = 0.078). The early response to at least four cycle of bortezomib before next chemotherapy may help predict PFS in patients with MM who are ineligible stem cell transplantation.

Phase 1 study of pomalidomide MTD, safety, and efficacy in patients with refractory multiple myeloma who have received lenalidomide and bortezomib

This phase 1 dose-escalation study determined the maximum tolerated dose (MTD) of oral pomalidomide (4 dose levels) administered on days 1 to 21 of each 28-day cycle in patients with relapsed and refractory multiple myeloma (RRMM). After four cycles, patients who progressed or had not achieved minimal response (serum and urine M-protein reduction of ≥ 25% and ≥ 50%) could receive dexamethasone 40 mg per week. Safety and efficacy were evaluated. Thirty-eight patients who had received both bortezomib and lenalidomide (median 6 prior therapies) were enrolled; 63% were refractory to both lenalidomide and bortezomib. There were four dose-limiting toxicities (grade 4 neutropenia) at 5 mg per day and so the MTD was 4 mg per day. Rates of peripheral neuropathy and venous thromboembolism were low (≤ 5%). Among the 38 patients enrolled (including 22 with added dexamethasone), 42% achieved minimal response or better, 21% achieved partial response or better, and 3% achieved complete response. Median duration of response, progression-free survival, and overall survival were 4.6, 4.6, and 18.3 months, respectively. Pomalidomide 4 mg per day on days 1 to 21 of each 28-day cycle, with or without dexamethasone (40 mg/week), has encouraging activity with manageable toxicity in RRMM, including those refractory to both lenalidomide and bortezomib. This study is registered at http://www.clinicaltrials.gov as #NCT00833833.

Combination chemotherapy increases cytotoxicity of multiple myeloma cells by modification of nuclear factor (NF)-κB activity

The nuclear factor (NF)-κB signaling pathway is critical in myeloma cell proliferation, inhibition of apoptosis, and emergence of therapy resistance. The chemotherapeutic drugs, dexamethasone (Dex) and bortezomib (BTZ), are widely used in clinical protocols for multiple myeloma (MM) and inhibit the NF-κB signaling pathway by distinct mechanisms. This study evaluates the efficacy of combination therapy with Dex and BTZ and investigates the mechanistic underpinning of endogenous and therapy-induced NF-κB activation in MM. Human myeloma cells and bone marrow stromal cells (BMSCs) were used in monocultures and cocultures to determine the cytotoxic effects of Dex and/or BTZ. Our results show that combined treatment of Dex with BTZ enhanced direct apoptosis of drug-sensitive and drug-resistant myeloma cells. In the presence of BMSCs, Dex plus BTZ combination inhibited ionizing radiation-induced interleukin 6 secretion from BMSCs and induced myeloma cytotoxicity. Mechanistically, Dex treatment increased IκBα protein and mRNA expression and compensated for BTZ-induced IκBα degradation. Dex plus BTZ combination inhibited basal and therapy-induced NF-κB activity with cytotoxicity in myeloma cells resistant to BTZ. Furthermore, combination therapy downregulated the NF-κB-targeted gene expression of interleukin 6 and manganese superoxide dismutase, which can induce chemo- and radio-resistance in MM. This study provides a mechanistic rationale for combining the NF-κB-targeting drugs Dex and BTZ in myeloma therapy and supports potential combinations of these drugs with radiotherapy and additional chemotherapeutic drugs for clinical benefit in MM.

How I treat plasma cell leukemia

Primary plasma cell leukemia (pPCL) is a rare and aggressive plasma cell proliferative disorder with a very poor prognosis and with distinct biologic, clinical, and laboratory features. Compared with multiple myeloma, pPCL presents more often with extramedullary involvement, anemia, thrombocytopenia, hypercalcemia, elevated serum β(2)-microglobulin and lactate dehydrogenase levels, as well as impaired renal function. Many of the genetic aberrations observed in newly diagnosed pPCL are typically found in advanced multiple myeloma. These cytogenetic abnormalities and mutations lead to increased proliferation, enhanced inhibition of apoptosis, escape from immune surveillance, and independence from the BM microenvironment, with changes in expression of adhesion molecules or chemokine receptors. The outcome of pPCL has improved with the introduction of autologous stem cell transplantation and combination approaches with novel agents, including bortezomib and immunomodulatory drugs, such as lenalidomide. In this review, we provide an overview of currently available therapeutic options with recommendations of how these treatment modalities can best be used to improve outcome for plasma cell leukemia patients.

Management of myeloma-associated renal dysfunction in the era of novel therapies

Multiple myeloma (MM) is a plasma cell neoplasm often associated with renal impairment (RI), with myeloma cast nephropathy recognized as the most common cause. While RI is present in over 50% of MM patients at some point in their disease course, it is associated with higher tumor burden, more aggressive disease, diminished quality of life, development of complications and increased mortality. The introduction of novel therapies, including bortezomib, lenalidomide and thalidomide, has revolutionized the management of MM. They are now considered first-line therapies in induction, maintenance and salvage therapy for MM. In addition to their anti-MM effect, they can improve outcome in patients with RI, especially when combined, and bortezomib with dexamethasone may have a renal protective effect. This review focuses on the use of these agents in patients with MM and RI, and evaluates their efficacy, safety, need for dose adjustment and impact on RI.

Perifosine plus lenalidomide and dexamethasone in relapsed and relapsed/refractory multiple myeloma: a Phase I Multiple Myeloma Research Consortium study

The combination of lenalidomide-dexamethasone is active in multiple myeloma (MM). Preclinical data showed that the Akt inhibitor, perifosine, sensitized MM cells to lenalidomide and dexamethasone, providing the rationale for this Phase I, multicentre, single-arm study to assess the safety and determine the maximum-tolerated dose (MTD) of perifosine-lenalidomide-dexamethasone in relapsed and relapsed/refractory MM. Patients received escalating doses of perifosine 50-100 mg daily and lenalidomide 15-25 mg once daily on days 1-21 of each 28-d cycle, plus dexamethasone 20-40 mg weekly thereafter, as indicated. Thirty-two patients were enrolled across four dose cohorts. MTD was not reached, with 31 patients evaluable for safety/tolerability. The most common all-causality grade 1-2 adverse events were fatigue (48%) and diarrhoea (45%), and grade 3-4 neutropenia (26%), hypophosphataemia (23%), thrombocytopenia (16%), and leucopenia (13%). Among 30 evaluable patients, 73% (95% confidence interval, 57·5-89·2%) achieved a minimal response or better, including 50% with a partial response or better. Median progression-free survival was 10·8 months and median overall survival 30·6 months. Response was associated with phospho-Akt in pharmacodynamic studies. Perifosine-lenalidomide-dexamethasone was well tolerated and demonstrated encouraging clinical activity in relapsed and relapsed/refractory MM.

MAGE-A3 expression is an adverse prognostic factor in diffuse large B-cell lymphoma

This study evaluates the prognostic value of MAGE-A3 expression in 28 diffuse large B-cell lymphoma (DLBCL) patients. A significant association was observed between MAGE-A3 expressions, assessed by quantitative real-time RT-polymerase chain reaction (PCR), with advanced stages of disease (P < 0.05). Elevated serum lactate dehydrogenase (LDH) levels and International Prognostic Index (IPI) score were significantly higher in MAGE-A3-positive patients (P = 0.025 and P = 0.004, respectively). Expression of MAGE-A3 was associated with poor response to treatment and a significantly shorter overall survival (P < 0.001). Our data address new information in the association of MAGE-A3 expression and poor prognosis in DLBCL patients.

Cancer/Testis Antigen MAGE-C1/CT7: new target for multiple myeloma therapy

Cancer/Testis Antigens (CTAs) are a promising class of tumor antigens that have a limited expression in somatic tissues (testis, ovary, fetal, and placental cells). Aberrant expression of CTAs in cancer cells may lead to abnormal chromosome segregation and aneuploidy. CTAs are regulated by epigenetic mechanisms (DNA methylation and acetylation of histones) and are attractive targets for immunotherapy in cancer because the gonads are immune privileged organs and anti-CTA immune response can be tumor-specific. Multiple myeloma (MM) is an incurable hematological malignancy, and several CTAs have been detected in many MM cell lines and patients. Among CTAs expressed in MM we must highlight the MAGE-C1/CT7 located on the X chromosome and expressed specificity in the malignant plasma cells. MAGE-C1/CT7 seems to be related to disease progression and functional studies suggests that this CTA might play a role in cell cycle and mainly in survival of malignant plasma cells, protecting myeloma cells against spontaneous as well as drug-induced apoptosis.

Novel therapeutic agents for the management of patients with multiple myeloma and renal impairment

Renal impairment is a major complication of multiple myeloma. Patients presenting with severe renal impairment represent a greater therapeutic challenge and generally have poorer outcome. However, once patients with renal impairment achieve remission, their outcomes are comparable with those of patients without renal impairment. Therapies that offer substantial activity in this setting are needed. Bortezomib, thalidomide, and lenalidomide have substantially improved the survival of patients with multiple myeloma. Here we review the pharmacokinetics, activity, and safety of these agents in patients with renal impairment. Bortezomib can be administered at the full approved dose and schedule in renally impaired patients; similarly, no dose reductions are required with thalidomide. The pharmacokinetics of lenalidomide is affected by its renal route of excretion, and dose adjustments are recommended for moderate/severe impairment. Substantial evidence has emerged showing that these novel agents improve outcomes of patients with renal impairment, including impairment reversal. Bortezomib, thalidomide, and lenalidomide (at the recommended doses) are active options for patients with mild to moderate impairment, although limited data are available for thalidomide. Information on lenalidomide-based combinations is still emerging, but the available data indicate considerable activity. Substantial evidence indicates that bortezomib-high-dose dexamethasone with or without a third drug (e.g., cyclophosphamide, thalidomide, or doxorubicin) is an appropriate option for patients with any degree of renal impairment.

The human immunodeficiency virus-1 protease inhibitor nelfinavir impairs proteasome activity and inhibits the proliferation of multiple myeloma cells in vitro and in vivo

BACKGROUND

Multiple myeloma is characterized by the accumulation of tumor plasma cells in the bone marrow. Despite therapeutic improvements brought by proteasome inhibitors such as bortezomib, myeloma remains an incurable disease. In a variety of human cancers, human immunodeficiency virus protease inhibitors (e.g. nelfinavir) effectively inhibit tumor progression, but their impact on myeloma is unknown. We assessed the in vitro and in vivo effects of nelfinavir on multiple myeloma.

DESIGN AND METHODS

The effects of nelfinavir (1-10 μM) on proteasome activity, proliferation and viability of myeloma cell lines and plasma cells from patients were assessed by measuring PERK, AKT, STAT3 and ERK1/2 phosphorylation and CHOP expression with immunoblotting or flow cytometry. The in vivo effect was assessed in NOD/SCID mice injected with luciferase expressing human myeloma cell lines and treated with nelfinavir at a dose of 75 mg/kg/day. Tumor progression was evaluated using a bioluminescent system.

RESULTS

Nelfinavir inhibited 26S chymotrypsin-like proteasome activity, impaired proliferation and triggered apoptosis of the myeloma cell lines and fresh plasma cells. It activated the pro-apoptotic unfolded protein response pathway by inducing PERK phosphorylation and CHOP expression. Cell death triggered by nelfinavir treatment correlated with decreased phosphorylation of AKT, STAT3 and ERK1/2. Nelfinavir enhanced the anti-proliferative activity of bortezomib, dexamethasone and histone deacetylase inhibitors and delayed tumor growth in a myeloma mouse model.

CONCLUSIONS

These results suggest that nelfinavir, used at a pharmacological dosage, alone or in combination, may be useful in the treatment of myeloma. Our data provide a preclinical basis for clinical trials using nelfinavir in patients with myeloma.

The Medical Research Council Myeloma IX trial: the impact on treatment paradigms

Osteolytic bone disease is a hallmark of symptomatic multiple myeloma. Bisphosphonates have been the mainstay of treatment to preserve skeletal integrity and prevent skeletal-related events in patients with myeloma-related bone disease. Recently, the MRC Myeloma IX trial demonstrated for the first time improved survival and delayed disease progression with the use of an intravenous amino-bisphosphonate, zoledronic acid, vs. an oral agent, clodronate, with intensive and non-intensive anti-myeloma treatment regimens in patients with newly diagnosed multiple myeloma. These results validate a large body of preclinical, translational and other clinical data suggesting anti-myeloma effects of amino-bisphosphonates. In addition, this trial also provided the first head-to-head evidence for superiority of one bisphosphonate over another (zoledronic acid vs. clodronate) for reducing skeletal morbidity in patients with multiple myeloma, as well as a prospective comparison of toxicities. Despite the use of non-bortezomib containing anti-myeloma treatment regimens in the MRC Myeloma IX trial, these results are encouraging and provide an impetus to continue to evaluate current treatment guidelines for myeloma-associated bone disease.

Multiple myeloma and diabetes

Multiple myeloma is a malignant plasma cell disorder that accounts for approximately 10% of all hematologic cancers. It is characterized by accumulation of clonal plasma cells, predominantly in the bone marrow. The prevalence of type 2 diabetes is increasing; therefore, it is expected that there will be an increase in the diagnosis of multiple myeloma with concomitant diabetes mellitus. The treatment of multiple myeloma and diabetes mellitus is multifaceted. The coexistence of the two conditions in a patient forms a major challenge for physicians.

Targeting MAGE-C1/CT7 expression increases cell sensitivity to the proteasome inhibitor bortezomib in multiple myeloma cell lines

The MAGE-C1/CT7 encodes a cancer/testis antigen (CTA), is located on the chromosomal region Xq26–27 and is highly polymorphic in humans. MAGE-C1/CT7 is frequently expressed in multiple myeloma (MM) that may be a potential target for immunotherapy in this still incurable disease. MAGEC1/CT7 expression is restricted to malignant plasma cells and it has been suggested that MAGE-C1/CT7 might play a pathogenic role in MM; however, the exact function this protein in the pathophysiology of MM is not yet understood. Our objectives were (1) to clarify the role of MAGE-C1/CT7 in the control of cellular proliferation and cell cycle in myeloma and (2) to evaluate the impact of silencing MAGE-C1/CT7 on myeloma cells treated with bortezomib. Myeloma cell line SKO-007 was transduced for stable expression of shRNA-MAGE-C1/CT7. Downregulation of MAGE-C1/CT7 was confirmed by real time quantitative PCR and western blot. Functional assays included cell proliferation, cell invasion, cell cycle analysis and apoptosis. Western blot showed a 70–80% decrease in MAGE-C1/CT7 protein expression in inhibited cells (shRNA-MAGE-C1/CT7) when compared with controls. Functional assays did not indicate a difference in cell proliferation and DNA synthesis when inhibited cells were compared with controls. However, we found a decreased percentage of cells in the G2/M phase of the cell cycle among inhibited cells, but not in the controls (p<0.05). When myeloma cells were treated with bortezomib, we observed a 48% reduction of cells in the G2/M phase among inhibited cells while controls showed 13% (empty vector) and 9% (ineffective shRNA) reduction, respectively (p<0.01). Furthermore, inhibited cells treated with bortezomib showed an increased percentage of apoptotic cells (Annexin V+/PI-) in comparison with bortezomib-treated controls (p<0.001). We found that MAGE-C1/CT7 protects SKO-007 cells against bortezomib-induced apoptosis. Therefore, we could speculate that MAGE-C1/CT7 gene therapy could be a strategy for future therapies in MM, in particular in combination with proteasome inhibitors.

Bortezomib in a phase 1 trial for patients with relapsed AL amyloidosis: cardiac responses and overall effects

BACKGROUND

Bortezomib is approved for the treatment of multiple myeloma and a role has been suggested in the treatment of systemic AL amyloidosis (AL).

METHODS

In this phase 1 dose-escalation portion of the first prospective study of single-agent bortezomib in AL, 31 patients with relapsed disease, including 14 (45%) with cardiac involvement, received bortezomib in seven dose cohorts on once-weekly (0.7, 1.0, 1.3, 1.6 mg/m(2)) and twice-weekly (0.7, 1.0, 1.3 mg/m(2)) schedules. Electrocardiographic, Holter and echocardiographic studies were evaluated in all patients to determine safety and response.

RESULTS

During therapy (median treatment period 210 days), no patient developed significant ventricular or supraventricular rhythm disturbance on 24-h Holter monitoring; however, no patient satisfied study criteria for cardiac response using echocardiographic assessment or New York Heart Association classification. Seven patients (23%) had a ≥ 10% fall in left ventricular ejection fraction, but only one met criteria for cardiac deterioration. The predominant cardiac adverse events were peripheral edema (23%), orthostatic hypotension (13%) and hypotension (10%). Two patients developed grade 3 congestive heart failure, which resolved following treatment interruption. In this Phase 1 portion, the maximum tolerated dose of bortezomib on either schedule was not reached. Hematologic responses occurred in 14 patients (45%), including seven (23%) complete responses. In non-responders mean left ventricular wall thickness increased during the course of treatment.

CONCLUSION

AL is frequently rapidly progressive; in these patients who had relapsed or progressed following previous conventional therapies, these results suggest that bortezomib may slow the progression of cardiac amyloid with limited toxicity.