Detection of clonal plasma cells in POEMS syndrome using multiparameter flow cytometry.

POEMS syndrome (polyneuropathy, organomegaly, endocrinopathy, monoclonal protein [M-protein], and skin changes) is a rare systemic disorder characterized by various symptoms caused by underlying plasma cell (PC) dyscrasia. Detection of monoclonal PCs is mandatory for the diagnosis of POEMS syndrome; however, the usefulness of EuroFlow-based next-generation flow cytometry (EuroFlow-NGF) in POEMS syndrome for detecting monoclonal PCs in bone marrow (BM) and the gating strategy suitable for flow cytometry study of POEMS syndrome remain unknown. We employed EuroFlow-NGF-based single-tube eight-color multiparameter flow cytometry (MM-flow) and established a new gating strategy (POEMS-flow) to detect the monoclonal PCs in POEMS syndrome, gating CD38 broadly from dim to bright and CD45 narrowly from negative to dim compared to MM-flow. MM-flow detected monoclonal PCs in 9/25 (36.0%) cases, including 2/2 immunofixation electrophoresis (IFE)-negative cases (100%). However, POEMS-flow detected monoclonal PCs in 18/25 cases (72.0%), including 2/2 IFE-negative cases (100%). POEMS-flow detected monoclonal PCs with immunophenotypes of CD19- in 17/18 (94.4%). In six cases where post-treatment samples were available, the size of the clones was significantly reduced after the treatment (P = 0.031). POEMS-flow can enhance the identification rate of monoclonal PCs in POEMS syndrome and become a valuable tool for the diagnosis of POEMS syndrome.

Metabolic reprogramming regulated by TRAF6 contributes to the leukemia progression.

TNF receptor associated factor 6 (TRAF6) is an E3 ubiquitin ligase that has been implicated in myeloid malignancies. Although altered TRAF6 expression is observed in human acute myeloid leukemia (AML), its role in the AML pathogenesis remains elusive. In this study, we showed that the loss of TRAF6 in AML cells significantly impairs leukemic function in vitro and in vivo, indicating its functional importance in AML subsets. Loss of TRAF6 induces metabolic alterations, such as changes in glycolysis, TCA cycle, and nucleic acid metabolism as well as impaired mitochondrial membrane potential and respiratory capacity. In leukemic cells, TRAF6 expression shows a positive correlation with the expression of O-linked N-acetylglucosamine (O-GlcNAc) transferase (OGT), which catalyzes the addition of O-GlcNAc to target proteins involved in metabolic regulation. The restoration of growth capacity and metabolic activity in leukemic cells with TRAF6 loss, achieved through either forced expression of OGT or pharmacological inhibition of O-GlcNAcase (OGA) that removes O-GlcNAc, indicates the significant role of O-GlcNAc modification in the TRAF6-related cellular and metabolic dynamics. Our findings highlight the oncogenic function of TRAF6 in leukemia and illuminate the novel TRAF6/OGT/O-GlcNAc axis as a potential regulator of metabolic reprogramming in leukemogenesis.

Nelarabine-induced rhabdomyolysis in a patient with T-cell acute lymphoblastic leukemia: a case report.

BACKGROUND: Nelarabine is an antineoplastic purine analog used for the treatment of refractory or relapsed T-cell acute lymphoblastic leukemia (T-ALL). The most prominent side effect of nelarabine are neurotoxicity and hematologic disorder, which are considered dose-limiting factors. Although clinical studies have reported myopathy due to nelarabine, actual detailed outcomes were not well-known initial approval. The incidence of nelarabine induced rhabdomyolysis has been reported at 2% in study in children. Cases of rhabdomyolysis have been reported in adults from medical facilities in the United Sates with renal dysfunction or severe muscle symptoms after administration of multiple courses of nelarabine. In this report, we discuss a case of rhabdomyolysis diagnosed after a single course of nelarabine. In this case, creatine kinase (CK) level was elevated in grade 4, without renal dysfunction and severe muscle symptoms. CASE PRESENTATION: A 46-year-old man from Japan was diagnosed with T-ALL and received a hematopoietic stem cell transplantation in first remission. However, the disease relapsed 6 months after transplantation. Nelarabine was selected as the next-line chemotherapeutic agent. The patient received 1500 mg/m2 of nelarabine on day 1 followed by a dose on days 3 and 5. CK levels, which were baseline before treatment, increased to grade 4 (18,620 IU/L) on the 8th day of treatment. He was diagnosed as rhabdomyolysis due to nelarabine with little possibility of other factors. He complained only of mild pain in his upper extremities and no other symptoms were noticed. The patient was managed with hydration. The pain lasted approximately 7 days, but there were no sequelae secondary to the rhabdomyolysis. Because of the elevation of CK in grade 4, we avoided re-administration. CONCLUSION: In the patient administrated nelarabine, CK level was elevated in grade 4, without other symptoms of rhabdomyolysis. The results suggest that CK may be elevated at the onset of rhabdomyolysis caused by nelarabine, even in the absence of other symptoms. Therefore, it was suggested that monitoring CK during nelarabine administration is important for detecting rhabdomyolysis before it becomes severe. We consider that CK should be monitored even in absence of symptoms.

Chronic active Epstein-Barr virus infection with marked pericardial effusion successfully treated with allogeneic peripheral blood stem cell transplantation.

A 23-year-old woman presented with a persistent fever and shortness of breath. Computed tomography showed marked pericardial effusion, hepatosplenomegaly, and cervical and mediastinal lymph node swelling. Epstein-Barr virus (EBV) antibody titers were abnormally elevated, and the copy number of EBV-DNA was increased in peripheral blood. Based on these observations, she was diagnosed with chronic active EBV infection (CAEBV). The EBV-infected cells in her peripheral blood were CD4(+)T lymphocytes. Fever and pericardial effusion improved following treatment with a combination of prednisolone, etoposide, and cyclosporine; however, peripheral blood EBV-DNA levels remained high. The patient underwent allogeneic peripheral blood stem cell transplantation from an EBV-seronegative, HLA-matched sibling donor, with fludarabine and melphalan conditioning. The post-transplantation course was uneventful, except for mild skin acute graft-versus-host disease (grade 2). EBV-DNA became undetectable in peripheral blood 98 days post transplantation. She has since been in good health without disease recurrence. CAEBV is a potentially fatal disease caused by persistent EBV infection of T lymphocytes or natural killer cells, thus requiring prompt treatment and allogeneic transplantation. Pericardial effusion is rarely observed in CAEBV and can impede its diagnosis. Therefore, we should be aware that patients may present with marked pericardial effusion as an initial manifestation of CAEBV.

The ß-Silyl Effect on the Memory of Chirality in Friedel-Crafts Alkylation Using Chiral α-Aryl Alcohols.

Iron salt-catalyzed Friedel-Crafts alkylation of chiral α-aryl alcohols with a trimethylsilyl group was found to proceed with retention of the configuration of the hydroxyl group as a leaving group. The memory of chirality of this system stems from the ß-silyl effect of the trimethylsilyl group on the carbocation intermediate.

Phenylenebis(ethynyl)-tethered bis-BINOL ligands for enantioselective catalyst based on dimeric TiIV aggregate.

Bis-BINOLs 7a-c in which two BINOL units are tethered by phenylenebis(ethynyl) groups react with titanium tetraisopropoxide (2 equiv) to form intramolecular dimeric titanium(IV) aggregates 2a-c. Of these, 2a,b with an o-phenylenebis(ethynyl) tether are stable in the presence of excess titanium tetraisopropoxide. Complex 2a exhibits a relatively high enantioselectivity in asymmetric addition of diethylzinc to an aldehyde. [structure: see text]