Multiple myeloma (MM) is a plasma cell neoplasm associated with a broad variety of genetic lesions. In spite of this genetic heterogeneity, MMs share a characteristic malignant phenotype whose underlying molecular basis remains poorly characterized. In the present study, we examined plasma cells from MM using a multi-epigenomics approach and demonstrated that, when compared to normal B cells, malignant plasma cells showed an extensive activation of regulatory elements, in part affecting coregulated adjacent genes. Among target genes up-regulated by this process, we found members of the NOTCH, NF-kB, MTOR signaling, and TP53 signaling pathways. Other activated genes included sets involved in osteoblast differentiation and response to oxidative stress, all of which have been shown to be associated with the MM phenotype and clinical behavior. We functionally characterized MM-specific active distant enhancers controlling the expression of thioredoxin (TXN), a major regulator of cellular redox status and, in addition, identified PRDM5 as a novel essential gene for MM. Collectively, our data indicate that aberrant chromatin activation is a unifying feature underlying the malignant plasma cell phenotype.

Aspirin reduced the rate of early graft thrombosis of renal transplants in this series but did not improve renal function or graft survival. A trend towards a lower rate of chronic allograft nephropathy was noted with aspirin treatment. These findings require confirmation in a prospective randomized trial.

Scleromyxedema is a rare skin and systemic mucinosis that is usually associated with monoclonal gammopathy (MG). In this French, multicenter, retrospective study of 33 patients, we investigated the clinical and therapeutic features of MG-associated scleromyxedema. Skin molecular signatures were analyzed using a transcriptomic approach. Skin symptoms included papular eruptions (100%), sclerodermoid features (91%), and leonine facies (39%). MG involved an IgG isotype in all patients, with a predominant λ light chain (73%). Associated hematologic malignancies were diagnosed in 4/33 patients (12%) (smoldering myeloma, n=2; chronic lymphoid leukemia, n=1; and refractory cytopenia with multilineage dysplasia n=1). Carpal tunnel syndrome (33%), arthralgia (25%) and dermato-neuro syndrome (DNS) (18%) were the most common systemic complications. One patient with mucinous cardiopathy died of acute heart failure. Intravenous immunoglobulin (HDIVig) treatment alone or in combination with steroids appeared to be quite effective in nonsevere cases (clinical complete response achieved in 13/31 patients). Plasma cell-directed therapies using lenalidomide and/or bortezomib with dexamethasone and HDIVig led to a significant improvement in severe cases (HDIVig-refractory or cases with central nervous system or cardiac involvement). The emergency treatment of DNS with combined plasmapheresis, HDIVig, and high-dose corticosteroids induced the complete remission of neurological symptoms in 4/5 patients. Quantitative reverse transcriptase-PCR (RT-PCR) analysis of 6 scleromyxedema skin samples showed significantly higher profibrotic pathway levels (transforming growth factor β (TGFβ) and collagen-1) than in healthy skin. Prospective studies targeting plasma cell clones and/or fibrotic pathways are warranted for long-term scleromyxedema management.