Successful preventive treatment with cyclosporine in a patient with relapsed/refractory immune-mediated thrombotic thrombocytopenic purpura: a case report and review of the literature.

Although salvage therapy with rituximab is effective in some cases of immune-mediated thrombotic thrombocytopenic purpura (iTTP) refractory to standard plasma exchange (PEX) and glucocorticoid treatment or relapsed after treatment, protocols to address the subsequent high recurrence rate have not been established. We describe the use of cyclosporine (CSA) to prevent recurrence in a patient with iTTP relapse after rituximab therapy, and present a literature review. A 24-year-old woman was diagnosed with iTTP and initially received PEX and high-dose methylprednisolone therapy. However, weekly rituximab therapy was also needed for inhibitor boosting to achieve additional immunosuppression during the initial treatment. Although the patient achieved clinical remission after weekly rituximab therapy, iTTP relapsed twice when glucocorticoids were tapered, and was treated with a triplet regimen consisting of PEX, high-dose methylprednisolone, and weekly rituximab. CSA was administered along with glucocorticoids as prophylaxis against iTTP relapse. The additional CSA therapy successfully maintained iTTP remission and allowed reduction of the corticosteroid dose. Our findings demonstrate that prophylactic CSA can potentially prevent iTTP recurrence in patients with a history of multiple relapses. Data from more cases must be accumulated to establish a useful prophylactic therapy for iTTP that is refractory even to rituximab.

Synergistic Effects of Venetoclax and Daratumumab on Antibody-Dependent Cell-Mediated Natural Killer Cytotoxicity in Multiple Myeloma.

The prognosis of multiple myeloma (MM) has drastically improved owing to the development of new drugs, such as proteasome inhibitors and immunomodulatory drugs. Nevertheless, MM is an extremely challenging disease, and many patients are still refractory to the existing therapies, thus requiring new treatment alternatives. Venetoclax is a selective, orally bioavailable inhibitor of BCL-2 that shows efficacy in MM not only as a single agent but also in combination therapy, especially for MM patients with translocation t(11;14). However, many patients are refractory to this drug. Here, we treated the MM cell lines KMS12PE and KMS27 with a combination treatment of venetoclax targeting BCL-2 and daratumumab targeting CD38 to evaluate the synergistic cytotoxicity of these drugs in vitro. MM cell lines were co-cultured with natural killer (NK) cells at an effector:target ratio of 0.3:1 in the presence of serial concentrations of daratumumab and venetoclax, and the resulting apoptotic MM cells were detected by flow cytometry using annexin V. These results indicated that the antibody-dependent cell-mediated NK cytotoxicity was enhanced in KMS12PE and KMS27 cells harboring t(11;14) with a high BCL-2 expression, suggesting that the combination treatment of venetoclax and daratumumab should be especially effective in patients with these characteristics.

Pretreatment Immature Platelet Fraction as a Surrogate of Reticulated Platelets Predicts the Response to Corticosteroids in Adults with Immune Thrombocytopenia.

OBJECTIVES: Reticulated platelets circulating in the blood reflect megakaryopoietic activity and platelet turnover and can be automatically and low-invasively measured as the immature platelet fraction (IPF) using a Sysmex XN hematocytometer. The present study retrospectively investigated whether or not the IPF can predict the treatment response to corticosteroids in adult patients with primary immune thrombocytopenia (ITP). METHODS: Forty-six patients who had been newly diagnosed with primary treatment-naïve ITP and started treatment with corticosteroids were analyzed. RESULTS: Among the 46 primary ITP patients, 33 (72%) responded to the treatment and 13 (28%) did not. The percentage of IPF (IPF%) among the nonresponders was significantly lower than that of the responders (6.6 vs. 16.0%; p < 0.001). In the receiver operating characteristics analysis, the optimum IPF% cut-off value for predicting the treatment response was 12%, with a specificity of 85% and a sensitivity of 76%. CONCLUSIONS: Our findings thus suggest that measuring the IPF% as a surrogate of reticulated platelets is useful to identify patients likely to respond to corticosteroids.

Cytopenia associated with copper deficiency.

Introduction: Due to an increased incidence of copper deficiency, we investigated adult patients who had low serum levels of copper with cytopenia at our hospital from March 2014 to March 2021. Methods: We retrospectively reviewed the clinical data of patients who had been diagnosed with cytopenia due to copper deficiency at the Aichi Medical University Hospital from March 2014 to March 2021. Results: In the 15 patients with cytopenia secondary to low serum copper level, 11 had cytopenia of two to three lineages; three (27%) had pancytopenia, and eight (73%) had bicytopenia. Of the 15 patients, nine (60%) underwent bone marrow examinations; three (30%) showed typical morphologic features associated with copper deficiency, such as multiple clear cytoplasmic vacuoles in erythroblasts and myeloid cells, and three (30%) showed dysplastic features as observed in myelodysplastic syndrome. Among the 14 (93%) patients who were treated with copper supplements, had cessation of zinc supplements, or both, 11 (73%) and eight (53%) showed normal copper levels and hematological improvement, respectively. Conclusion: Copper deficiency is more common than expected and should be considered in patients with unexplained cytopenia.

Novel Interleukin-6 Inducible Gene PDZ-Binding Kinase Promotes Tumor Growth of Multiple Myeloma Cells.

[Figure: see text] Multiple myeloma (MM) remains an intractable hematological malignancy, despite recent advances in anti-MM drugs. Here, we show that role of PDZ binding kinase (PBK) in MM tumor growth. We identified that interleukin-6 (IL-6) readily increases PBK expression. Kaplan-Meier analysis showed that the MM patients with higher expression of PBK have a significant shorter survival time compared with those with moderate/lower expression of PBK. Knockout of PBK dramatically suppressed in vivo tumor growth in MM cells, while genome editing of PBK changing from asparagine to serine substitution (rs3779620) slightly suppresses the tumor formation. Mechanistically, loss of PBK increased the number of apoptotic cells with concomitant decrease in the phosphorylation level of Stat3 as well as caspase activities. A novel PBK inhibitor OTS514 significantly decreased KMS-11-derived tumor growth. These findings highlight the novel oncogenic role of PBK in tumor growth of myeloma, and it might be a novel therapeutic target for the treatment of patients with MM.

[Emergence of Howell-Jolly bodies in a patient with splenic hypoplasia complicated by fulminant pneumococcal infection].

We report the case of a patient with fulminant pneumococcal infection along with the presence of Howell-Jolly bodies (HJBs) and splenic hypoplasia at the onset. A 71-year-old man developed fever during outpatient chemotherapy for IgG-κ multiple myeloma and was diagnosed with septic shock due to invasive pneumococcal infection. HJBs were observed on peripheral blood smears at this visit. Computed tomography revealed marked hypoplasia of spleen, suggesting the presence of hyposplenic function. Antibacterial therapy was initiated and the pneumococcal infection was cured; however, there was no notable change in his splenic hypoplasia. Splenic hypoplasia can be associated with fatal infections; hence, care should be taken when it is found in the elderly and in patients with cancer and those receiving immunosuppressive treatment. Even today, when automated hematology analyzers have become common, not all patients with hematological diseases have peripheral blood smears checked with a normal optical microscope. This study suggests that HJBs may be useful for simple and rapid screening of splenic hypofunction. The importance of detecting HJBs in peripheral blood smears with a normal optical microscope should be re-recognized.

Biallelic loss of FAM46C triggers tumor growth with concomitant activation of Akt signaling in multiple myeloma cells.

Loss of heterozygosity or mutation of the family with sequence similarity 46, member C (FAM46C) gene on chromosome band 1p12 is associated with shorter overall survival of patients with multiple myeloma (MM). In this study, using human MM cell lines (KMS-11, OCI-My5, and ANBL-6), we generated FAM46C-/- cell clones and examined the effect of disruption of FAM46C on cell survival and cellular signaling. Cell proliferation assays showed increased clonogenicity of FAM46C-/- KMS-11 cells compared to WT cells. Xenograft experiments showed significantly shorter overall survival of mice harboring the FAM46C-/- cell-derived tumors than mice with the FAM46CWT cell-derived tumors. Notably, levels of phosphorylated Akt and its substrates increased both in vitro and in vivo in the FAM46C-/- cells compared to WT cells. In addition, caspase activities decreased in the FAM46C-/- cells. Results of gene set enrichment analysis showed that loss of FAM46C significantly activated serum-responsive genes while inactivating phosphatase and tensin homolog (PTEN)-related genes. Mechanistically, loss of FAM46C decreased the PTEN activity, number of apoptotic cells, and caspase activities. PF-04691502, a selective PI3K inhibitor, suppressed the augmented phosphorylation of Akt and its substrate FoxO3a. Treatment with afuresertib (a specific Akt inhibitor) in combination with bortezomib additively decreased FAM46C-/- MM cell survival. Collectively, this study is the first to report that loss of FAM46C triggers the concomitant activation of the PI3K-Akt signaling pathway, which might be a therapeutic target for MM with abnormalities in the FAM46C gene.

Favorable prognostic phenotype in myelodysplastic syndrome with der(1;7)(q10;p10).

Unbalanced translocation der(1;7)(q10;p10) is a characteristic chromosomal abnormality in myelodysplastic syndrome (MDS). The current study revealed that among 13 MDS patients with der(1;7)(q10;p10), seven cases with no apparent dysplasia also had low numbers of myeloblasts in the bone marrow and a 3-year survival rate of 86%; in contrast, the remaining six cases had a 3-year survival rate of 0% (P = .003). It was therefore suggested that MDS patients with der(1;7)(q10;p10) are classified into a distinct group with a favorable prognosis and another distinct group with a very poor prognosis.

Establishment and characterization of a novel vincristine-resistant diffuse large B-cell lymphoma cell line containing the 8q24 homogeneously staining region.

Chromosome band 8q24 is the most frequently amplified locus in various types of cancers. MYC has been identified as the primary oncogene at the 8q24 locus, whereas a long noncoding gene, PVT1, which lies adjacent to MYC, has recently emerged as another potential oncogenic regulator at this position. In this study, we established and characterized a novel cell line, AMU-ML2, from a patient with diffuse large B-cell lymphoma (DLBCL), displaying homogeneously staining regions at the 8q24 locus. Fluorescence in situ hybridization clearly detected an elevation in MYC copy numbers corresponding to the homogenously staining region. In addition, a comparative genomic hybridization analysis using high-resolution arrays revealed that the 8q24 amplicon size was 1.4 Mb, containing the entire MYC and PVT1 regions. We also demonstrated a loss of heterozygosity for TP53 at 17p13 in conjunction with a TP53 frameshift mutation. Notably, AMU-ML2 cells exhibited resistance to vincristine, and cell proliferation was markedly inhibited by MYC-shRNA-mediated knockdown. Furthermore, genes involved in cyclin D, mTOR, and Ras signaling were downregulated following MYC knockdown, suggesting that MYC expression was closely associated with tumor cell growth. In conclusion, AMU-ML2 cells are uniquely characterized by homogenously staining regions at the 8q24 locus, thus providing useful insights into the pathogenesis of DLBCL with 8q24 abnormalities.

Novel combined Ato-C treatment synergistically suppresses proliferation of Bcr-Abl-positive leukemic cells in vitro and in vivo.

Chronic myelogenous leukemia (CML) accounts for 15-20% of all leukemias affecting adults. Despite recent advances in the development of specific Bcr-Abl tyrosine kinase inhibitors (TKIs), some CML patients suffer from relapse due to TKI resistance. Here, we assessed the efficacy of a novel combinatorial arsenic trioxide (ATO) and cisplatin (CDDP) treatment (Ato-C) in human Bcr-Abl-positive leukemic cells. Combination index analyses revealed that a synergistic interaction of ATO and CDDP elicits a wide range of effects in K562, KU-812, MEG-A2, and KCL-22 cells. Notably, Ato-C synergistically enhanced apoptosis and decreased the survival of both acquired TKI-resistant CML cells and the cells expressing mutant Bcr-AblT315I. In addition, Ato-C dramatically decreased the phosphorylation level of forkhead transcription factor FOXO1/3a and STAT5 as well as c-Myc protein level. Interestingly, results of gene set enrichment analysis showed that Ato-C significantly downregulates the expression of MYC- and/or E2F1-target genes. Furthermore, Ato-C significantly suppressed the proliferation of MEG-A2-derived tumor when compared with that following monotherapy in vivo. Collectively, these results suggest that combined Ato-C treatment could be a promising alternative to the current therapeutic regime in CML.