ARK5 enhances cell survival associated with mitochondrial morphological dynamics from fusion to fission in human multiple myeloma cells.

5' adenosine monophosphate-activated protein kinase-related kinase 5 (ARK5) is involved in mitochondrial ATP production and associated with poor prognosis of multiple myeloma (MM). However, the molecular mechanisms of ARK5 in MM remain largely unknown. This study examined the pathogenic role of ARK5 in mitochondria by using genetically modified isogenic cell clones with or without ARK5 in human myeloma cell lines, KMS-11 and Sachi, which overexpress ARK5. The biallelic knockout of ARK5 (ARK5-KO) inhibited cell proliferation, colony formation, and migration with increased apoptosis. Mitochondrial fusion was enhanced in ARK5-KO cells, unlike in ARK5 wild-type (ARK5-WT) cells, which exhibited increased mitochondrial fission. Furthermore, ARK5-KO cells demonstrated a lower phosphorylated dynamin-related protein 1 at serine 616, higher protein expression of mitofusin-1 (MFN1) and MFN2, optic atrophy 1 with a lower level of ATP, and higher levels of lactate and reactive oxygen species than ARK5-WT cells. Our findings suggest that ARK5-enhanced myeloma cells can survive associated mitochondrial fission and activity. This study first revealed the relationship between ARK5 and mitochondrial morphological dynamics. Thus, our outcomes show novel aspects of mitochondrial biology of ARK5, which can afford a more advanced treatment approach for unfavorable MM expressing ARK5.

Pseudocarcinomatous Hyperplasia of the Nose and Necrotic Tracheitis Associated with Acute Myeloid Leukemia: A Case Report.

A 29-year-old woman who had been diagnosed with acute myeloid leukemia presented with persistent grade-4 febrile neutropenia (FN) after initial chemotherapy with idarubicin and cytarabine. Despite intensive treatment, FN persisted. Subsequently, her nose became reddish and swollen, obstructing the nasal cavities. Computed tomography revealed swelling of the nostrils and an irregular tracheal surface. Debridement of the nasal lesion and a bronchoscopic biopsy of the tracheal lesion were also performed. A histopathological examination revealed pseudocarcinomatous hyperplasia (PCH) of the nose and necrotizing tracheitis. Both nasal PCH and necrotizing tracheitis ameliorated when the patient recovered from leukocytopenia.

Efficacy and safety of modified BLd therapy for Japanese patients with transplant-ineligible multiple myeloma.

The BLd regimen, which is a triplet regimen of bortezomib (Bor), lenalidomide (Len), and dexamethasone (Dex), is effective against newly diagnosed multiple myeloma (NDMM). However, non-hematological toxicities, such as peripheral neuropathy (PN), often hamper long-term continuation of the regimen, particularly in older adult patients. In this study, we examined the efficacy and safety of the modified BLd regimen with reduced-intensity Bor and standard-dose Len. The chemotherapy regimen consisted of 1.3 mg/m2 Bor administered subcutaneously on days 1 and 8, 25 mg Len administered on days 1-14, and 20 mg Dex on days 1-2 and 8-9 of a 3 week cycle for 8 cycles, followed by a 4 week cycle of Dex (40 mg weekly). Among the 30 patients enrolled, 60.0% (95% CI 40.6-77.3) had a very good partial response or better, and the best overall response rate was 96.7% (95% CI 82.8-99.9). Eight patients (26.7%) achieved a complete response. Grade 3 or higher PN was not observed and hematological toxicity was the most common adverse event. The modified BLd regimen showed favorable efficacy with a manageable safety profile, which suggests it could be a treatment option for transplant-ineligible NDMM.

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.

CD52 is a novel target for the treatment of FLT3-ITD-mutated myeloid leukemia.

Internal tandem duplication (ITD) of FMS-like tyrosine kinase 3 (FLT3) confers poor prognosis and is found in approximately 25% of cases of acute myeloid leukemia (AML). Although FLT3 inhibitors have shown clinical benefit in patients with AML harboring FLT3-ITD, the therapeutic effect is limited. Here, to explore alternative therapeutics, we established a cellular model of monoallelic FLT3ITD/WT cells using the CRISPR-Cas9 system in a human myeloid leukemia cell line, K562. cDNA microarray analysis revealed elevated CD52 expression in K562-FLT3ITD/WT cells compared to K562-FLT3WT/WT cells, an observation that was further confirmed by quantitative real-time-PCR and flow cytometric analyses. The elevated expression of CD52 in K562-FLT3ITD/WT cells was decreased in wild-type FLT3 (FLT3-WT) knock-in K562-FLT3ITD/WT cells. In K562-FLT3ITD/WT cells, a STAT5 inhibitor, pimozide, downregulated CD52 protein expression while an AKT inhibitor, afuresertib, did not affect CD52 expression. Notably, an anti-CD52 antibody, alemtuzumab, induced significant antibody-dependent cell-mediated cytotoxicity (ADCC) in K562-FLT3ITD/WT cells compared to K562-FLT3WT/WT cells. Furthermore, alemtuzumab significantly suppressed the xenograft tumor growth of K562-FLT3ITD/WT cells in severe combined immunodeficiency (SCID) mice. Taken together, our data suggested that genetically modified FLT3-ITD knock-in human myeloid leukemia K562 cells upregulated CD52 expression via activation of STAT5, and alemtuzumab showed an antitumor effect via induction of ADCC in K562-FLT3ITD/WT cells. Our findings may allow establishment of a new therapeutic option, alemtuzumab, to treat leukemia with the FLT3-ITD mutation.

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.

Safety and pharmacokinetics of polatuzumab vedotin in Japanese patients with relapsed/refractory B-cell non-Hodgkin lymphoma: a phase 1 dose-escalation study.

OBJECTIVE: A phase 1 dose-escalation study of polatuzumab vedotin (pola) was conducted to assess safety, pharmacokinetics and preliminary antitumor activity of pola in Japanese patients with relapsed/refractory B-cell non-Hodgkin lymphoma. METHODS: Patients received pola (1.0 or 1.8 mg/kg) intravenously every 21 days until disease progression or intolerance. Intra-patient dose escalation was prohibited. Tolerability was determined by the standard 3 + 3 rule. Blood sampling was performed to characterize pharmacokinetics. Antitumor activity was evaluated through computed tomography and bone marrow sampling. RESULTS: Four patients received pola 1.0 mg/kg; three received 1.8 mg/kg. Patients had follicular lymphoma (n = 4) or diffuse large B-cell lymphoma (n = 3), median age of 62 years, received a median of 3 prior therapies; six were female. Pola was well tolerated in both cohorts, with no dose-limiting toxicities observed. The most common adverse event was peripheral sensory neuropathy (n = 4). Grade 3 adverse events were cholecystitis and neutrophil count decreased (one each; both 1.0 mg/kg), and syncope and cataract (one each; both 1.8 mg/kg). The plasma half-life of antibody-conjugate monomethyl auristatin E was 4.43-7.98 days, and systemic exposure of unconjugated monomethyl auristatin E was limited in both cohorts. Four patients achieved objective responses (three complete, one partial) without disease progression during the study. CONCLUSIONS: This phase 1 dose-escalation study demonstrated that pola has an acceptable safety profile and offers encouraging antitumor activity to Japanese patients with relapsed/refractory B-cell non-Hodgkin lymphoma. Pola 1.8 mg/kg, the recommended phase 2 dose, was tolerable in Japanese patients.

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.

Combining T-cell-based immunotherapy with venetoclax elicits synergistic cytotoxicity to B-cell lines in vitro.

Alterations of B-cell lymphoma 2 (BCL-2) family proteins contribute to the survival of B-cell malignancies. Recently, venetoclax, a BCL-2 inhibitor, was approved for B-cell chronic lymphocytic leukemia therapy and is being investigated in clinical trials for a variety of hematologic cell malignancies. Furthermore, combination therapy with other molecularly targeted drugs was reported to be more effective than monotherapy. However, combining venetoclax with immunotherapy based on T-cells has not been tested. Because both venetoclax and granzyme B activate the mitochondrial apoptosis pathway by targeting different BCL-2 family molecules, it is possible that combinations of venetoclax with immunotherapy will be effective treatments. We examined the effect of combining venetoclax with immunotherapy using an in vitro model system involving cytomegalovirus (CMV) pp65 antigen-specific cytotoxic T-cells (CMV-CTLs) as the effector cells and CMVpp65 antigen-expressing B-cell lines as the target cells. Cytotoxicity of CMV-CTLs to the target B-cell lines was enhanced by venetoclax with combination index values of 0.47-0.83. This suggests that venetoclax synergizes with T-cell-based immunotherapy to affect B-cell malignancies. Interestingly, venetoclax synergized not only with antigen-specific cytotoxicity but also with nonspecific cytotoxicity. Importantly, CMV-CTLs could be expanded in the presence of venetoclax at the maximum concentration (5 µM) that induced apoptosis in resting CMV-CTLs. B-cell lymphoma-extra large (BCL-xL) expression in CMV-CTLs increased transiently after activation by CMVpp65-transfected B-cell lines, indicating that the expression of BCL-xL was important for the effectiveness of combination treatment with venetoclax. These findings suggest that T-cell-based immunotherapy combined with venetoclax is effective against B-cell malignancies.

[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.

Treatment outcomes of chronic-phase chronic myeloid leukemia with resistance and/or intolerance to a 1st-line tyrosine kinase inhibitor in Japan: the results of the New TARGET study 2nd-line.

We herein report the results of the New TARGET study 2nd-line, which collected data on patients with chronic-phase (CP) chronic myeloid leukemia (CML) who received a 2nd-line tyrosine kinase inhibitor (TKI) because of resistance and/or to a 1st-line TKI. A total of 98 patients were enrolled intolerance between April 2010 and March 2013, and 82 patients were analyzed. The median age was 54 years (range 22-88 years). Seventy-six patients (93%) received imatinib as the 1st-line TKI. Forty-five (55%) and 37 (45%) patients began nilotinib and dasatinib treatments at entry, respectively. First-line TKI treatment achieved complete hematological response in 79 patients (96%) and complete cytogenetic response (CCyR) in 49 patients (60%), respectively. Nine patients (11%) had BCR-ABL1 kinase domain point mutations at enrollment. The estimated 3-year progression-free-survival rate after enrollment was 98.7% (95% CI 91.1-99.8%). Overall, the probabilities of achieving CCyR and a major molecular response were 89.3% (95% CI 81.4-94.8%) and 87.2% (95% CI 78.1-93.8%), respectively. There were no new safety issues. This study demonstrated that CML-CP patients in Japan who are resistant and/or intolerant to a 1st-line TKI can achieve an extremely good outcome by 2nd-line TKI treatment.

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.

[Sporadic late-onset nemaline myopathy with monoclonal gammopathy of undetermined significance mimicking POEMS syndrome].

A 40-year-old female presented with a skin rash, hepatosplenomegaly, hypothyroidism, IgG-λ monoclonal gammopathy, slightly elevated serum VEGF levels, and >1-year history of weakness in the posterior cervical muscles. Based on these symptoms and her clinical course, she was suspected of having POEMS syndrome. However, because there was no sign of peripheral neuropathy (PN), the criteria for the diagnosis of POEMS syndrome were not met. Consequently, she continued follow-up and was under close observation as an outpatient. She complained of slowly progressive dyspnea that was identified as type 2 respiratory failure requiring non-invasive positive pressure ventilation. She received systemic chemotherapy, including thalidomide and dexamethasone, as the respiratory failure was predominantly a result of POEMS-associated PN. Although the skin eruptions improved upon treatment, respiratory failure gradually worsened, and she required mechanical ventilation. The patient was suspected of having sporadic late-onset nemaline myopathy with monoclonal gammopathy of undetermined significance (SLONM-MGUS), because of resistant to chemotherapy and second opinion suggestion. A thigh muscle biopsy revealed the presence of nemaline rods and led to the definitive diagnosis of SLONM-MGUS. Unfortunately, she was unable to receive autologous stem cell transplantation, and finally died because of progressive respiratory failure. SLONM-MGUS is an extremely rare disease but should be considered as a critical, monoclonal-protein related condition.

Prediction of high risk for death in patients with follicular lymphoma receiving rituximab plus cyclophosphamide, doxorubicin, vincristine, and prednisolone in first-line chemotherapy.

Risk stratification of patients with relapsed and refractory follicular lymphoma (FL) remains challenging. Recently, much attention has been paid to the impact of early progression of disease within 2 years of diagnosis (early POD) on subsequent survival. The aim of this study was to clarify the clinical features and prognostic factors of patients with FL who experienced early POD. Data were available for 94 patients diagnosed with FL (clinical stage II-IV) who had received immunochemotherapy. Early POD was seen in 20 % of these patients. The Cox proportional hazards model showed worse overall survival (OS) in the patients with early POD compared with those without early POD (5-year OS rates 48 % vs. 96 %, P < 0.0001). In multivariate analysis, early POD (P = 0.003) and poor performance status (P = 0.006) remained a significant factor for subsequent OS. In Follicular Lymphoma International Prognostic Index (FLIPI)- and Follicular Lymphoma International Prognostic Index-2 (FLIPI2)-adjusted Cox regression analysis, early POD was associated with markedly reduced OS with a hazard ratio of 11.2 [95 % confidence interval (CI) 3.13-40.3, P < 0.001] and 13.5 (95 % CI 3.22-56.3, P < 0.003), respectively. Among patients who had early POD, high levels of serum lactate dehydrogenase (LDH) both at the time of initial diagnosis and first progression could be associated with worse survival (2-year OS rates 33 vs. 92 %, P < 0.0001). Evaluation of LDH levels at the time of initial diagnosis and first progression may be important to define patients who were associated with worse prognosis. Risk stratification of patients with early POD could lead to improved clinical outcomes for FL patients. Further research is needed to investigate its value for decision making.

Phase I study of once weekly treatment with bortezomib in combination with lenalidomide and dexamethasone for relapsed or refractory multiple myeloma.

Proteasome inhibitors (PIs) in combination with immunomodulatory drugs (IMiDs) have been shown to be effective against relapsed/refractory multiple myeloma (RRMM). To determine the optimal dosing schedule of once weekly bortezomib (BTZ) combined with lenalidomide (LEN) and dexamethasone (DEX), especially in the outpatient setting, we conducted a phase I dose escalation study. A 21-day cycle of BTZ 1.3 mg/m(2) on days 1 and 8, LEN 10 mg/day (cohort 1) or 15 mg/day (cohort 2) on days 1-14, and DEX 20 mg/day on days 1, 2, 8, and 9 was administered. Three patients were enrolled in each cohort. No dose-limiting toxicity was observed in either cohort. Although hematological toxicities estimated as >grade 3 were common, non-hematological toxicities of grade 3 or higher were rare. Two cases of newly diagnosed peripheral neuropathy (PN) were observed, while no grade 3/4 PN was observed. Two patients achieved partial response and two achieved stable disease. The recommended doses of BTZ and LEN were determined to be 1.3 mg/m(2) and 15 mg, respectively. Combination therapy of once weekly BTZ with LEN and DEX was well tolerated and shows promise as a regimen for patients with RRMM previously treated with both PIs and IMiDs.