Proteasome beta subunit pharmacogenomics: gene resequencing and functional genomics.

Purpose: The proteasome is a multisubunit cellular organelle that functions as a nonlysosomal threonine protease. Proteasomes play a critical role in the degradation of proteins, regulating a variety of cellular processes, and they are also the target for antineoplastic proteasome inhibitors. Genetic variation in proteasome subunits could influence both proteasome function and response to drug therapy.

Improvement of cast nephropathy with plasma exchange depends on the diagnosis and on reduction of serum free light chains.

Cast nephropathy is the most common cause of renal disease in multiple myeloma, however, treatment with plasma exchange remains controversial even after 3 randomized controlled studies. We sought to determine the importance of diagnostic confirmation and goal directed therapy in the treatment of cast nephropathy in forty patients with confirmed multiple myeloma and renal failure who underwent plasma exchange. A positive renal response was defined as a decrease by half in the presenting serum creatinine and dialysis independence.

Appraisal of immunoglobulin free light chain as a marker of response.

The immunoglobulin free light chain (FLC) assay is an invaluable tool for following patients with oligosecretory plasma cell dyscrasia. Baseline values have also been shown to be prognostic in all plasma cell disorders tested. A looming question, however, is the role it should play in following myeloma patients with disease that is measurable using serum and urine electrophoresis.

Effect of tissue shipping on plasma cell isolation, viability, and RNA integrity in the context of a centralized good laboratory practice-certified tissue banking facility.

The Multiple Myeloma Research Consortium has established a tissue bank for the deposition of bone marrow samples from patients with multiple myeloma to be mailed and processed under good laboratory practices. To date, over 1,000 samples have been collected. At this time, limited information is available on shipped bone marrow aspirates in regards to cell viability, yield, purity, and subsequent RNA yield and quality.

R-(-)-gossypol (AT-101) activates programmed cell death in multiple myeloma cells.

Objective: Bcl-2 family proteins play a critical role in malignancies by regulating the balance between cell survival and apoptosis. R-(-)-gossypol (AT-101) is a small molecule that mimics the BH3 domain of cellular Bcl-2 inhibitors and interferes with the function of prosurvival Bcl-2 proteins. We examined the cytotoxicity of AT-101 in the context of multiple myeloma, a fatal hematological malignancy.

Anti-CD20 monoclonal antibody therapy in multiple myeloma.

CD20 is a particularly appealing target that is expressed on the surface of almost all B cells, with no significant shedding, secretion or internalization. In contrast to the demonstrated efficacy of anti-CD20 strategies in various B-cell lymphoproliferative disorders, the role of such therapy in multiple myeloma is undetermined and controversial. The expression of CD20 by myeloma cells is heterogeneous, and can be detected only in 13-22% of patients.

Myeloma in patients younger than age 50 years presents with more favorable features and shows better survival: an analysis of 10 549 patients from the International Myeloma Working Group.

We analyzed the presenting features and survival in 1689 patients with multiple myeloma aged younger than 50 years compared with 8860 patients 50 years of age and older. Of the total 10 549 patients, 7765 received conventional therapy and 2784 received high-dose therapy. Young patients were more frequently male, had more favorable features such as low International Staging System (ISS) and Durie-Salmon stage as well as less frequently adverse prognostic factors including high C-reactive protein (CRP), low hemoglobin, increased serum creatinine, and poor performance status.

Genetic aberrations and survival in plasma cell leukemia.

Plasma cell leukemia (PCL) is an aggressive and rare hematological malignancy that originates either as primary disease (pPCL) or as a secondary leukemic transformation (sPCL) of multiple myeloma (MM). We report here the genetic aberrations and survival of 80 patients with pPCL or sPCL and make comparisons with 439 cases of MM. pPCL presents a decade earlier than sPCL (54.

Improved survival in multiple myeloma and the impact of novel therapies.

Treatments for myeloma have expanded in the last decade, but it is not clear if the introduction of novel therapies and the increased use of high-dose therapy have translated into better outcome for patients with myeloma. We examined the outcome of 2 groups of patients seen at a single institution, one from time of diagnosis and the other from the time of relapse, to examine the survival trends over time. Among 387 patients relapsing after stem-cell transplantation, a clear improvement in overall survival from the time of relapse was seen, with those relapsing after 2000 having a median overall survival of 23.

Novel therapy with 2-methoxyestradiol for the treatment of relapsed and plateau phase multiple myeloma.

Purpose: 2-Methoxyestradiol (2ME2) is an endogenous product of estradiol metabolism with antiangiogenic and antineoplastic properties. We report on the first phase II trial of 2ME2 in multiple myeloma.

Experimental Design: 2ME2 was administered orally at a dose of 1,000 mg daily.

Long-term results of response to therapy, time to progression, and survival with lenalidomide plus dexamethasone in newly diagnosed myeloma.

Objective: To determine the long-term effects of a combined regimen of lenalidomide and dexamethasone (Rev-Dex) on time to progression, progression-free survival, and overall survival (OS) in patients with multiple myeloma.

Patients And Methods: From March 2004 through October 2004, 34 patients were registered for the study. They were treated with 25 mg/d of lenalidomide on days 1 through 21 of a 28-day cycle and 40 mg/d of dexamethasone on days 1 through 4, 9 through 12, and 17 through 20 of each cycle.

Promiscuous mutations activate the noncanonical NF-kappaB pathway in multiple myeloma.

Activation of NF-kappaB has been noted in many tumor types, however only rarely has this been linked to an underlying genetic mutation. An integrated analysis of high-density oligonucleotide array CGH and gene expression profiling data from 155 multiple myeloma samples identified a promiscuous array of abnormalities contributing to the dysregulation of NF-kappaB in approximately 20% of patients. We report mutations in ten genes causing the inactivation of TRAF2, TRAF3, CYLD, cIAP1/cIAP2 and activation of NFKB1, NFKB2, CD40, LTBR, TACI, and NIK that result primarily in constitutive activation of the noncanonical NF-kappaB pathway, with the single most common abnormality being inactivation of TRAF3.

Comparison of bromcresol green and agarose protein electrophoresis for quantitation of serum albumin in multiple myeloma.

Background: The International Staging System for multiple myeloma has increased the importance of accurate measurement of serum albumin. Two common albumin assays, bromcresol green (BCG) and agarose gel protein electrophoresis (PEL), frequently yield discordant results, creating confusion regarding which assay is superior for use in myeloma.

Methods: We measured albumin by BCG on a Roche Modular system, by PEL with a Helena SPIFE SPE Vis agarose gel, and by immunonephelometry performed on a Dade Behring BNII nephelometer.

ABT-737, an inhibitor of Bcl-2 family proteins, is a potent inducer of apoptosis in multiple myeloma cells.

Disruption of pathways leading to programmed cell death plays a major role in most malignancies, including multiple myeloma (MM). ABT-737 is a BH3 mimetic small-molecule inhibitor that binds with high affinity to Bcl-2 and Bcl-xL, preventing the sequestration of proapoptotic molecules and shifting the cell survival/apoptosis balance toward apoptosis induction. In this study, we show that ABT-737 is cytotoxic to MM cell lines, including those resistant to conventional therapies, and primary tumor cells.

Molecular dissection of hyperdiploid multiple myeloma by gene expression profiling.

Hyperdiploid multiple myeloma (H-MM) is the most common form of myeloma. In this gene expression profiling study, we show that H-MM is defined by a protein biosynthesis signature that is primarily driven by a gene dosage mechanism as a result of trisomic chromosomes. Within H-MM, four independently validated patient clusters overexpressing nonoverlapping sets of genes that form cognate pathways/networks that have potential biological importance in multiple myeloma were identified.

Treatment of newly diagnosed multiple myeloma based on Mayo Stratification of Myeloma and Risk-adapted Therapy (mSMART): consensus statement.

Multiple myeloma is a neoplastic plasma cell dyscrasia that on a yearly basis affects nearly 17,000 individuals and kills more than 11,000. Although no cure exists, many effective treatments are available that prolong survival and improve the quality of life of patients with this disease. The purpose of this consensus is to offer a simplified, evidence-based algorithm of decision making for patients with newly diagnosed myeloma.

A practical guide to defining high-risk myeloma for clinical trials, patient counseling and choice of therapy.

Clinical outcomes for multiple myeloma (MM) are highly heterogeneous and it is now clear that pivotal genetic events are the primary harbingers of such variation. These findings have broad implications for counseling, choice of therapy and the design and interpretation of clinical investigation. Indeed, as in acute leukemias and non-hodgkins lymphoma, we believe it is no longer acceptable to consider MM a single disease entity.

6q deletion in Waldenström macroglobulinemia is associated with features of adverse prognosis.

Fluorescence in situ hybridisation (FISH) is an effective technique for the cytogenetic analysis of Waldenström macroglobulinemia (WM), but the potential impact of molecular cytogenetics on disease evolution and as a prognostic marker is still unknown. Deletion of the long arm of chromosome 6 (6q-) is the most frequent cytogenetic abnormality in WM. This study analysed the prevalence of this aberration in 102 WM patients, and correlated it with disease characteristics.

Prognostic value of chromosome 1q21 gain by fluorescent in situ hybridization and increase CKS1B expression in myeloma.

A specific role for increased level of expression of CKS1B, as a consequence of chromosome 1q21 copy number gain, has been postulated as both pathogenic, as well as a powerful clinical prognostic factor in multiple myeloma (MM). The purpose of this study is to determine the clinical associations and prognostic impact of copy number gain at chromosome 1q21 (with a bacteria artificial chromosome clone containing CKS1B) and CKS1B gene level of expression in MM. We studied the chromosome region 1q21 for copy number change in a cohort of myeloma patients treated by high-dose therapy with stem-cell rescue (HDT) (n = 159).

The activity of lenalidomide with or without dexamethasone in patients with primary systemic amyloidosis.

Primary systemic amyloidosis (AL) is an incurable plasma cell disorder. Lenalidomide, especially in conjunction with dexamethasone, is highly active in patients with multiple myeloma. We studied the toxicity and efficacy of lenalidomide in patients with AL.

6q deletion discriminates Waldenström macroglobulinemia from IgM monoclonal gammopathy of undetermined significance.

IgM monoclonal gammopathy of undetermined significance (IgM MGUS) and Waldenström macroglobulinemia (WM) are sometimes clinically difficult to distinguish. In our previous study, deletion of the long arm of chromosome 6 (6q) was found in about half of WM patients. To further clarify the area of minimal deletion at 6q (6q-) and to address the issue of whether 6q- occurs in IgM MGUS, 12 IgM MGUS and 38 WM patients were studied by fluorescence in situ hybridization using probes targeting different chromosomal segments of 6q.