Three years of maintenance with VRD in multiple myeloma: results of total therapy IIIB with a 15-year follow-up.

ABSTRACT: The total therapy (TT) IIIB phase 2 study incorporated bortezomib into tandem melphalan-based hematopoietic stem cell transplantation with dexamethasone, thalidomide, cisplatin, doxorubicin, cyclophosphamide, and etoposide for induction/consolidation and bortezomib, lenalidomide, and dexamethasone (VRD) for maintenance in patients with newly diagnosed multiple myeloma (MM). This updated analysis presents a 15.4-year median follow-up. Of 177 patients, 21% patients had gene expression profile (GEP)-defined high-risk MM. 15-year progression free survival (PFS) was 27.9%. Median PFS was better in GEP-defined low-risk patients at 7.8 years and in International Staging System stage 1 patients at 8.7 years. Overall, median OS was 9.1 years, and 15-year overall survival (OS) was 35.9%. GEP-defined low-risk patients' median OS was 11.2 years, and that of GEP-defined high-risk patients was 2.8 years. There was no difference in OS between TT IIIB and TT IIIA. This study includes the longest follow-up of patients treated with maintenance VRD reported to date. In patients with GEP-defined low-risk, nearly half and one-third of patients without ongoing treatment showed no signs of progression at 10 and 15 years, respectively. One-third of patients survived more than 15 years, but 3 years of VRD maintenance did not improve outcomes for patients with GEP-defined high-risk MM. The study was registered on www.clinicaltrials.gov as #NCT00572169.

MAF protein mediates innate resistance to proteasome inhibition therapy in multiple myeloma.

Multiple myeloma (MM) patients with the t(14;16) translocation have a poor prognosis, and unlike other molecular subgroups, their outcome has not improved with the introduction of bortezomib (Bzb). The mechanism underlying innate resistance of MM to Bzb is unknown. In the present study, we have investigated how MAF overexpression impacts resistance to proteasome inhibitor (PI) therapy (Bzb and carfilzomib). High levels of MAF protein were found in t(14;16) cell lines; cell lines from the t(4;14) subgroup had intermediate levels, whereas cell lines from the other subgroups had low levels. High expression of MAF protein in t(14;16) was associated with significantly higher PI half-maximum inhibitory concentration values compared with other molecular subgroups. PI exposure abrogated glycogen synthase kinase 3ß (GSK3ß)-mediated degradation of MAF protein, resulting in increased MAF protein stability and PI resistance. Subsequent studies using loss-of-function and gain-of-function models showed that silencing MAF led to increased sensitivity to PIs, enhanced apoptosis, and activation of caspase-3, -7, -8, -9, poly (ADP-ribose) polymerase, and lamin A/C. In contrast, overexpression of MAF resulted in increased resistance to PIs and reduced apoptosis. These results define the role of MAF and GSK3 in the resistance of t(14;16) MM to PIs and identifies a novel mechanism by which MAF protein levels are regulated by PIs, which in turn confers resistance to PIs.

Evidence of an epigenetic origin for high-risk 1q21 copy number aberrations in multiple myeloma.

Multiple myeloma is a B-cell malignancy stratified in part by cytogenetic abnormalities, including the high-risk copy number aberrations (CNAs) of +1q21 and 17p(-). To investigate the relationship between 1q21 CNAs and DNA hypomethylation of the 1q12 pericentromeric heterochromatin, we treated in vitro peripheral blood cultures of 5 patients with balanced constitutional rearrangements of 1q12 and 5 controls with the hypomethylating agent 5-azacytidine. Using G-banding, fluorescence in situ hybridization, and spectral karyotyping, we identified structural aberrations and copy number gains of 1q21 in the treated cells similar to those found in patients with cytogenetically defined high-risk disease. Aberrations included 1q12 triradials, amplifications of regions juxtaposed to 1q12, and jumping translocations 1q12. Strikingly, all 5 patients with constitutional 1q12 rearrangements showed amplifications on the derivative chromosomes distal to the inverted or translocated 1q12 region, including MYCN in 1 case. At the same time, no amplification of the 1q21 region was found when the 1q12 region was inverted or absent. These findings provide evidence that the hypomethylation of the 1q12 region can potentially amplify any genomic region juxtaposed to it and mimic CNAs found in the bone marrow of patients with high-risk disease.

Artesunate overcomes drug resistance in multiple myeloma by inducing mitochondrial stress and non-caspase apoptosis.

Although novel drugs have contributed immensely to improving outcomes of patients with multiple myeloma (MM), many patients develop drug resistance and ultimately succumb to MM. Here, we show that artesunate, an anti-malarial drug, reliably induces cell death in vitro in naïve as well as drug-resistant MM cells at concentrations shown to be safe in humans. Artesunate induced apoptosis predominantly through the non-caspase mediated pathway by primarily targeting mitochondria and causing outer mitochondrial membrane permeabilization that led to cytosolic and subsequent nuclear translocation of mitochondrial proteins apoptosis inducing factor (AIF) and endonuclease G (EndoG). Nuclear translocation of AIF and EndoG was accompanied by low levels of reactive oxygen species (ROS) and increased mitochondrial production of superoxide. These effects were present before apoptosis was evident and were related to intracellular levels of bivalent iron (Fe+2). Artesunate's unique mechanism probably was at least partially responsible for, its ability to act synergistically with multiple anti-myeloma agents. Our findings suggest that artesunate acts through iron to affect the mitochondria and induce low ROS and non-caspase-mediated apoptosis. Its potency, toxicity profile, and synergism with other drugs make it an intriguing new candidate for MM treatment.

Hepatitis B reactivation in patients with multiple myeloma and isolated positive hepatitis B core antibody: a call for greater cognizance.

Hepatitis B virus (HBV) reactivation is a well-established complication of severe immunosuppression in patients with hematologic malignancy and positive hepatitis B surface antigen (HBsAg). Patients who receive high-dose chemotherapy, corticosteroids, rituximab, or have a bone marrow transplant are particularly at increased risk for HBV reactivation. However, limited information is available in the literature regarding HBV reactivation in patients with isolated anti-HBc, particularly in the setting of multiple myeloma (MM). We report two cases of HBV reactivation in MM patients with isolated anti-HBc positive with a rather atypical presentation. In conclusion, our cases highlight that clinicians need to be cognizant about this potentially fatal but preventable complication of chemotherapy and immunosuppression.

Patterns of central nervous system involvement in relapsed and refractory multiple myeloma.

BACKGROUND: Invasion of CNS in MM is an extremely rare occurrence that is associated with advanced disease with poor prognosis. PATIENTS AND METHODS: Our MM database identified 35 CNS MM cases presenting between January 1996 and March 2012. Descriptive analyses were performed on available data on patient characteristics, disease course, and outcomes. RESULTS: The mean age at diagnosis was 55.4 years; 23.5% (n = 8) patients had elevated levels of beta-2-microglobulin > 5.5 mg/L; 68.6% (n = 24) of patients had elevated lactate dehydrogenase (LDH) levels (≥ 2 times upper limit of normal); and 14% (n = 5) of patients had secondary plasma cell leukemia. Magnetic resonance imaging (MRI), which was performed in 34 patients, showed diffuse or localized leptomeningeal disease in 20 patients (58.8%). Monoclonal malignant plasma cells were found by CSF analysis in all 35 patients. In total, 31 patients received chemotherapy, including intrathecal chemotherapy as a part of their treatment, with a median survival of 4 months after CNS MM diagnosis. DISCUSSION: In our experience, CNS MM is an aggressive terminal disease feature associated with high beta-2-microglobulin level, high LDH level, and secondary plasma cell leukemia. This study highlights an unmet need in this subset of patients with high-risk, relapsed or refractory MM. CONCLUSION: Achieving adequate CSF penetration while limiting the off-target effects needs to be considered in MM-specific novel drug development.

Probable invasive aspergillosis without prespecified radiologic findings: proposal for inclusion of a new category of aspergillosis and implications for studying novel therapies.

BACKGROUND: The European Organization for Research and Treatment of Cancer (EORTC) and the Mycosis Study Group (MSG) definition of invasive aspergillosis used in clinical trials lacks sensitivity. We hypothesize that giving lower weight to the prespecified radiologic findings in patients with a positive serum galactomannan index test result will improve the definition's diagnostic sensitivity. METHODS: The medical records of 121 patients with 125 cases of invasive aspergillosis treated at a referral cancer institute from January 2003 through December 2009 were reviewed. Aspergillosis was diagnosed as EORTC-MSG proven or probable (controls, 83) or probable invasive aspergillosis without prespecified radiologic criteria (cases, 42). The latter differed from the former by the inclusion of patients whose pulmonary infiltrates, although well described in invasive aspergillosis, do not fulfill EORTC-MSG invasive aspergillosis requirements. The host, clinical, and mycologic characteristics and survival of cases and controls served as end points. RESULTS: A total of 114 (91%) of 125 patients had multiple myeloma. Patients had a median age was 65 years (range, 26-81 years), and 74 were male. All had received antineoplastic therapy, including stem cell transplantation (58 [46%]). Aspergillosis involved lungs (88 patients), sinuses (9 patients), or both (28 patients). Except for higher median baseline platelet count and shorter duration of neutropenia among cases, there were no statistically significant differences between groups on all predefined end points, including 4-, 6-, and 12-week survival. Eleven of 26 cases were reclassified as controls on the basis of subsequent imaging. CONCLUSIONS: Except for less well-circumscribed consolidations, the host, clinical, radiologic, and mycologic characteristics and outcome of patients with probable invasive aspergillosis but without prespecified radiologic criteria are similar to those with EORTC-MSG invasive aspergillosis. Enrolling such patients in clinical trials of novel therapies will increase the pool of eligible study participants and improve trial speed and efficiency.