[Concentration of gilteritinib in the cerebrospinal fluid of a patient with relapsed FLT3-ITD positive acute myeloid leukemia with optic nerve involvement].

A 72-year-old woman with relapsed FLT3-ITD-positive acute myeloid leukemia was treated with gilteritinib and achieved complete remission with incomplete hematological recovery. However, two months later, she developed optic nerve infiltration and lost vision in her right eye while maintaining hematological remission on gilteritinib. Intrathecal injection of cytotoxic drugs reduced the number of blasts in the cerebrospinal fluid (CSF), but her vision did not recover. At the onset of optic nerve infiltration, at a dose of 80 mg/day gilteritinib, the plasma trough and CSF levels of gilteritinib were 151.9 ng/ml and 1.9 ng/ml, respectively, with a central nervous system (CNS) penetration rate of 1.3%. Hematologic progressive disease (PD) was detected after 40 days, and the patient died one month later. Target sequencing at the time of hematologic PD revealed the FLT3 F691L mutation, which is known to confer resistance to gilteritinib. In this patient, pharmacokinetic (low CNS penetration of gilteritinib) and pharmacodynamic (acquisition of a drug resistance mutation) mechanisms were thought to be responsible for the CNS relapse and hematologic PD, respectively. We believe this is a valuable case to report considering the scarcity of data on CNS penetration of FLT3 inhibitors and their effects on CNS disease in the literature.

Modelling and drug targeting of a myeloid neoplasm with atypical 3q26/MECOM rearrangement using patient-specific iPSCs.

Structural variations involving enhancer hijacking induce aberrant oncogene expression and cause tumorigenesis. A rare translocation, t(3;8)(q26.2;q24), is associated with MECOM and MYC rearrangement, causing myeloid neoplasms with a dismal prognosis. The most recent World Health Organization classification recognises myeloid neoplasms with MECOM rearrangement as acute myeloid leukaemia (AML) with defining genetic abnormalities. Recently, the increasing use of induced pluripotent stem cell (iPSC) technology has helped elucidate the pathogenic processes of haematological malignancies. However, its utility for investigating enhancer hijacking in myeloid neoplasms remains unclear. In this study, we generated iPSC lines from patients with myelodysplastic syndromes (MDS) harbouring t(3;8)(q26.2;q24) and differentiated them into haematopoietic progenitor cells to model the pathophysiology of MDS with t(3;8)(q26.2;q24). Our iPSC model reproduced the primary patient's MECOM expression changes and histone H3 lysine 27 acetylation (H3K27ac) patterns in the MECOM promoter and MYC blood enhancer cluster (BENC). Furthermore, we revealed the apoptotic effects of the bromodomain and extra-terminal motif (BET) inhibitor on iPSC-derived MDS cells by suppressing activated MECOM. Our study demonstrates the usefulness of iPSC models for uncovering the precise mechanism of enhancer hijacking due to chromosomal structural changes and discovering potential therapeutic drug candidates for cancer treatment.

The impact of renal function on initial therapy in transplant-ineligible multiple myeloma patients.

The prognosis for multiple myeloma (MM) patients has improved with the advent of new drugs, but the prognosis with renal impairment (RI) is poor. The choice of treatment in such cases is critical, but there are no set criteria. We examined the impact of RI on initial therapy in transplant-ineligible MM patients. We selected symptomatic MM patients who met the following criteria: age ≥ 65 years, fit, and ineligible for transplantation from the database. We analyzed the impact of age, treatment, International Staging System (ISS) stage, karyotype abnormalities, performance status, and estimated glomerular filtration rate (GFR < 50 or ≥ 50 ml/min/1.73m2) on overall survival (OS). We also analyzed the OS by eGFR for each treatment. We selected 349 symptomatic MM patients. The regimens used were lenalidomide, bortezomib and dexamethasone (RVd), daratumumab, bortezomib, melphalan, and prednisolone (D-VMP), daratumumab, lenalidomide and dexamethasone (D-Rd) and daratumumab, bortezomib, and dexamethasone (D-Vd) in 184, 41, 74 and 50 patients, respectively. The median age was 74 years old; ISS stage was I/II/III in 85/112/131 patients; and 161 patients showed eGFR < 50. The OS was shorter with ISS stage III (p = 0.029) and eGFR < 50 (p < 0.001) by multivariate analysis. The OS under the RVd/D-Rd regimens were significantly shorter for patients with eGFR < 50, but OS under the D-VMP/D-Vd regimens were not significantly different between patients with eGFR < 50 and eGFR ≥ 50. The OS of the transplant-ineligible MM patients with higher ISS stage and RI was poor. Initial treatment with a D-VMP/D-Vd regimen might be less affected by RI.

An atlas of transcribed enhancers across helper T cell diversity for decoding human diseases.

Transcribed enhancer maps can reveal nuclear interactions underpinning each cell type and connect specific cell types to diseases. Using a 5' single-cell RNA sequencing approach, we defined transcription start sites of enhancer RNAs and other classes of coding and noncoding RNAs in human CD4+ T cells, revealing cellular heterogeneity and differentiation trajectories. Integration of these datasets with single-cell chromatin profiles showed that active enhancers with bidirectional RNA transcription are highly cell type-specific and that disease heritability is strongly enriched in these enhancers. The resulting cell type-resolved multimodal atlas of bidirectionally transcribed enhancers, which we linked with promoters using fine-scale chromatin contact maps, enabled us to systematically interpret genetic variants associated with a range of immune-mediated diseases.

Selection and characterization of aptamers targeting the Vif-CBFß-ELOB-ELOC-CUL5 complex.

The viral infectivity factor (Vif) of human immunodeficiency virus 1 forms a complex with host proteins, designated as Vif-CBFß-ELOB-ELOC-CUL5 (VßBCC), initiating the ubiquitination and subsequent proteasomal degradation of the human antiviral protein APOBEC3G (A3G), thereby negating its antiviral function. Whilst recent cryo-electron microscopy (cryo-EM) studies have implicated RNA molecules in the Vif-A3G interaction that leads to A3G ubiquitination, our findings indicated that the VßBCC complex can also directly impede A3G-mediated DNA deamination, bypassing the proteasomal degradation pathway. Employing the Systematic Evolution of Ligands by EXponential enrichment (SELEX) method, we have identified RNA aptamers with high affinity for the VßBCC complex. These aptamers not only bind to the VßBCC complex but also reinstate A3G's DNA deamination activity by inhibiting the complex's function. Moreover, we delineated the sequences and secondary structures of these aptamers, providing insights into the mechanistic aspects of A3G inhibition by the VßBCC complex. Analysis using selected aptamers will enhance our understanding of the inhibition of A3G by the VßBCC complex, offering potential avenues for therapeutic intervention.

Successful Second CBT for Graft Failure After First CBT for Adult-Onset Familial Hemophagocytic Lymphohistiocytosis Type 3: A Case Report.

Familial hemophagocytic lymphohistiocytosis (FHL) is a rare inherited autosomal recessive immune deficiency that usually manifests during infancy or early childhood, rarely occurring in adults. Hematopoietic stem cell transplantation (HSCT) is the only curative treatment for FHL. However, optimal conditioning regimens for adult-onset FHL have not yet been established. Herein, we report a case of adult-onset FHL. A 37-year-old man presented with fever, liver dysfunction, and pancytopenia, which improved temporarily with corticosteroid therapy. However, he later developed encephalitis and myelitis. Genetic analysis revealed rare variants of UNC13D (c.2367+1 g>a and c.2588 g>a), which were compound heterozygous pathogenic mutations. FHL type 3 was diagnosed, and treatment based on the hemophagocytic lymphohistiocytosis (HLH) 1994 protocol was initiated. The patient underwent cord blood transplantation (CBT) with myeloablative conditioning using fludarabine, melphalan, and total-body irradiation (TBI), which resulted in graft rejection. The patient was successfully rescued by a second CBT following reduced-intensity conditioning with fludarabine, cyclophosphamide, and TBI. Although graft failure is an important complication especially in CBT, it could be managed by appropriate treatment, and that cord blood would be a promising alternative source with the advantages of rapidity and avoidance of related donors with a high risk of harboring the same genetic mutation.

The lymphocyte/monocyte ratio predicts the efficacy of isatuximab plus pomalidomide in multiple myeloma patients.

BACKGROUND: Isatuximab, an anti-CD38 antibody, has been widely used in treatments for patients with relapsed/refractory multiple myeloma (MM). Despite its high efficacy, not all patients achieve a lasting therapeutic response with isatuximab. OBJECTIVE: We tried to identify biomarkers to predict the effectiveness of isatuximab by focusing on the host's immune status before treatment. METHODS: We retrospectively analyzed the cases of 134 relapsed/refractory MM patients in the Kansai Myeloma Forum database who had received only a first isatuximab treatment. RESULTS: Among the 134 patients, an isatuximab, pomalidomide and dexamethasone (Isa-PD) regimen, isatuximab, carfilzomib and dexamethasone (Isa-KD) regimen and isatuximab and/or dexamethasone (Isa-D) regimen were used in 112, 15 and 7 patients, respectively. The median age at treatment, number of prior treatment regimens, and progression-free survival (PFS) were 71, 6, and 6.54 months, respectively. Multivariate analysis showed that the PFS under the Isa-PD regimen was longer in patients with higher lymphocyte/monocyte ratio (LMR ≥ 4), fewer prior treatment regimens (< 6), and no use of prior daratumumab treatment. The OS under the Isa-PD regimen was longer in patients with higher white blood cell counts (WBC counts ≥ 3000/µL) and higher LMR. The PFS under the Isa-D regimen was longer in patients with fewer prior treatment regimens in univariate analysis, but no parameters were correlated with PFS/OS under the Isa-KD regimen. CONCLUSION: We found that the patients with higher LMR (≥ 4) could obtain longer PFS and OS under the Isa-PD regimen. Other cohort studies of isatuximab treatment might be necessary to substantiate our results.

Utilizing red blood cell distribution width (RDW) as a reliable biomarker to predict treatment effects after chimeric antigen receptor T cell therapy.

Chimeric antigen receptor T cell (CAR-T) therapy is an effective treatment for B cell malignancies. A certain fraction of patients, however, experience post-CAR-T relapse, and due to the difficulty of precise relapse prediction, biomarkers that can predict the strength and duration of CAR-T efficacy are needed before CAR-T infusion. Therefore, we performed a single-center cohort study including 91 diffuse large B cell lymphoma (DLBCL) patients treated with CAR-T in order to identify such a new prognostic biomarker. After confirming that each of the already reported prognostic parameters (disease status at leukapheresis, primary refractoriness, number of treatment lines, CD3+ cell counts at leukapheresis) has only limited predictive performance, we established a new composite parameter by integrating these four variables, and found that it predicts progression-free survival (PFS) after CAR-T infusion with statistical significance. Moreover, after comprehensive correlation analyses of this new composite parameter with all individual laboratory variables, we determined that the standard deviation of red blood cell distribution width (RDW-SD) at leukapheresis shows significant correlation with the composite parameter and may be a prognostic biomarker (R2 = 0.76, p = 0.02). Validation analysis indicated that a higher RDW-SD is significantly associated with poorer PFS after CAR-T cell therapy (HR, 3.46, P = 0.03). Thus, this study suggests that a single parameter, RDW-SD at leukapheresis, is a novel, useful biomarker that can be obtained early to predict therapeutic effects of CAR-T cell therapy. Post-CAR-T maintenance or re-induction therapies should be adopted for higher risk patients, who may relapse after CAR-T therapy.

Population Pharmacokinetic Modeling of Posaconazole in Japanese Patients Receiving Fungal Prophylaxis.

BACKGROUND: Posaconazole is a vital drug to treat and prevent invasive fungal infections. Several factors, such as sex, body weight, total serum proteins, dietary intake, and severe mucositis, affect posaconazole pharmacokinetics (PKs). However, the relevance of other factors that affect the PKs of posaconazole in hematopoietic stem cell transplantation (HSCT) is unknown. This study explored factors influencing the PKs of posaconazole in HSCT recipients and nontransplant patients with hematological diseases. METHODS: The authors conducted a single-institution, retrospective study. Forty-two Japanese inpatients receiving oral posaconazole tablets as prophylaxis for fungal infections were enrolled in this study. A one-compartment model with first-order absorption was used as the structural pharmacokinetic model. A population PK (PopPK) analysis was performed using a nonlinear mixed-effects modeling program, using a first-order conditional estimation method with interactions. Perl-speaks-NONMEM and R were used to evaluate the goodness of fit and visualize the output. RESULTS: In 29% of the enrolled patients, the serum concentration of posaconazole was <0.5 mcg/mL, considered the effective range. PopPK analysis revealed that the patient had undergone HSCT within 1 year, diarrhea occurred more than 5 times a day, and aspartate aminotransferase were covariates that influenced apparent clearance (CL/F). The CL/F of posaconazole was 1.43-fold higher after HSCT and 1.26-fold higher during diarrhea. CONCLUSIONS: PopPK analysis revealed that HSCT, diarrhea, and aspartate aminotransferase were factors associated with the CL/F of posaconazole. The trough concentration of posaconazole may be below the therapeutic range in a few patients with diarrhea and/or after HSCT. As invasive fungal infections in patients with hematologic diseases can be life-threatening, therapeutic drug monitoring of posaconazole is strongly recommended, and patients should be carefully monitored.

Longitudinal analysis of genomic mutations in SARS-CoV-2 isolates from persistent COVID-19 patient.

A primary reason for the ongoing spread of coronavirus disease 2019 (COVID-19) is the continuous acquisition of mutations by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). However, the mechanism of acquiring mutations is not fully understood. In this study, we isolated SARS-CoV-2 from an immunocompromized patient persistently infected with Omicron strain BF.5 for approximately 4 months to analyze its genome and evaluate drug resistance. Although the patient was administered the antiviral drug remdesivir (RDV), there were no acquired mutations in RDV binding site, and all isolates exhibited susceptibility to RDV. Notably, upon analyzing the S protein sequence of the day 119 isolate, we identified mutations acquired by mutant strains emerging from the BF.5 variant, suggesting that viral genome analysis in persistent COVID-19 patients may be useful in predicting viral evolution. These results suggest mutations in SARS-CoV-2 are acquired during long-term viral replication rather than in response to antiviral drugs.

Sustained remission after cord blood transplantation for breast cancer with lung metastases and myelodysplastic syndrome.

Allogenic hematopoietic stem cell transplantation (allo-HSCT) is not a standard therapy for solid cancer because of its high toxicity and insufficient evidence levels. However, the potential graft-versus-solid-tumor (GVT) effect of this therapy has been discussed. Many case reports have also described treatment effects of allo-HSCT in patients with hematologic malignancies and active solid tumors. A 38-year-old woman treated with fulvestrant and abemaciclib for recurrent breast cancer with multiple lung metastases was diagnosed with myelodysplastic syndrome (MDS) with increased blasts 2. She was classified as adverse risk by the 2017 European LeukemiaNet risk stratification and as very high risk by the Molecular International Prognostic Scoring System. Breast cancer treatment was interrupted and venetoclax and azacitidine therapy was started. Complete hematologic response was achieved after three cycles. However, multiple lung metastases from the breast cancer remained. The patient then underwent umbilical cord blood transplantation. She has maintained complete remission of MDS as of 1 year post-transplantation, without serious complications. Lung metastatic activity on FDG-PET/CT scan also completely disappeared by half a year post-transplantation, and this response has continued as of 1 year post-transplantation. This favorable treatment course suggests the existence of a GVT effect.

Efficacy of elotuzumab for multiple myeloma deteriorates after daratumumab: a multicenter retrospective study.

Elotuzumab-based regimens are sometimes selected for multiple myeloma treatment after daratumumab-based regimens. However, there has been insufficient discussion on the efficacy of elotuzumab after daratumumab. We used Kansai Myeloma Forum registration data in a multicenter retrospective evaluation of the efficacy of elotuzumab after daratumumab. Overall survival (OS) rate and time to next treatment (TTNT) were significantly worse in the cohort given elotuzumab after daratumumab (Dara cohort, n = 47) than in the cohort with no history of daratumumab administration before elotuzumab (No-Dara cohort, n = 80, OS: P = 0.03; TTNT: P = 0.02; best response: P < 0.01). In the Dara cohort, OS and TTNT rates were worse with sequential elotuzumab use after daratumumab than with non-sequential (OS: P = 0.02; TTNT: P = 0.03). In patients given elotuzumab < 180 days after daratumumab, OS (P = 0.08) and best response (P = 0.21) tended to be worse, and TTNT was significantly worse (P = 0.01), than in those given elotuzumab after ≥ 180 days. These findings were confirmed by subgroup analyses and multivariate analyses. Monoclonal-antibody-free treatment might be preferable after daratumumab-based regimens. If possible, elotuzumab-based regimens should be considered only ≥ 180 days after daratumumab use.

[Severe consciousness disturbance after cord blood transplantation for relapsed T lymphoblastic lymphoma].

T-lymphoblastic leukemia/lymphoma (T-ALL/LBL) has a poor prognosis. Nelarabine has recently shown relatively good results in patients with relapsed or refractory T-ALL/LBL, but requires careful monitoring for neurological complications. A 50-year-old man with early recurrence of T-LBL after allogenic peripheral blood stem cell transplantation received nelarabine monotherapy and achieved complete remission after 1 cycle. He then received umbilical cord blood transplantation, and experienced sustained disturbance of consciousness. He later died of multiple organ failure, and autopsy suggested that nelarabine-induced leukoencephalopathy had caused the disturbance of consciousness. This case suggests that physicians should carefully monitor patients for neurological complications and consider imaging follow-up and consultation with a neurologist.

Clinical Impact of Cytokine Release Syndrome on Prolonged Hematotoxicity after Chimeric Antigen Receptor T Cell Therapy: KyoTox A-Score, a Novel Prediction Model.

Prolonged hematotoxicity is the most common long-term adverse event in chimeric antigen receptor T cell therapy (CAR-T). To evaluate the impact on prolonged cytopenia of inflammatory status after CAR T infusion, we performed a single-center retrospective study and analyzed patients with B cell lymphomas after CAR-T. Among 90 patients analyzed at 90 days after infusion, the cumulative incidence was 57.5% for prolonged neutropenia, 36.7% for anemia, and 49.8% for thrombocytopenia. Patients who experienced cytokine release syndrome (CRS) had significantly higher incidence and longer duration of prolonged cytopenia. In addition, we found that among patients with grade 1 CRS, those with a longer duration of CRS-related symptoms (>5 days; grade 1b in modified CRS grading [m-CRS]) had a significantly higher incidence and longer duration of prolonged cytopenia than those whose CRS-related symptoms resolved within 5 days (grade 1a m-CRS). Multivariate analysis revealed that a higher m-CRS grade (grade 1b or 2; hazard ratio [HR], 2.42), higher peak CRP (≥10 mg/dL; HR, 1.66), longer duration of elevated CRP (≥10 days; HR, 1.83), and a decrease in serum inorganic phosphorus concentration (≥30% from baseline; HR, 1.95) were associated with significantly higher cumulative incidence of prolonged neutropenia, as well as anemia and thrombocytopenia. Using these factors, we developed a new predictive scoring model for prolonged hematotoxicity, the KyoTox a-score, which can successfully stratify the incidence and duration of cytopenia independent of the existing model, CAR-HEMATOTOX, which is based on laboratory data at lymphodepletion. Thus, this newly developed post-CAR-T inflammation-dependent score is accurate and useful for predicting prolonged hematotoxicity.

Clinical impact and characteristics of erythroid dysplasia in adult aplastic anaemia: Results from a multicentre registry.

Morphological dysplasia in haematopoietic cells, defined by a 10% threshold in each lineage, is one of the diagnostic criteria for myelodysplastic neoplasms. Dysplasia limited to the erythroid lineage has also been reported in some cases of aplastic anaemia (AA); however, its significance remains unclear. We herein examined the impact of erythroid dysplasia on immunosuppressive therapy responses and survival in AA patients. The present study included 100 eligible AA patients without ring sideroblasts. Among them, 32 had dysplasia in the erythroid lineage (AA with minimal dysplasia [mini-D]). No significant sex or age differences were observed between AA groups with and without erythroid dysplasia. In severe/very severe AA and non-severe AA patients, a response to anti-thymocyte globulin + ciclosporin within 12 months was observed in 80.0% and 60.0% of AA with mini-D and 42.9% and 90.0% of those without dysplasia, with no significant difference (p = 0.29 and p = 0.24 respectively). Overall survival and leukaemia-free survival did not significantly differ between the groups. Collectively, the present results indicate that the presence of erythroid dysplasia did not significantly affect clinical characteristics or outcomes in AA patients, suggesting that its presence in AA is acceptable. Therefore, erythroid dysplasia should not exclude an AA diagnosis.

Canonical BAF complex regulates the oncogenic program in human T-cell acute lymphoblastic leukemia.

ABSTRACT: Acute leukemia cells require bone marrow microenvironments, known as niches, which provide leukemic cells with niche factors that are essential for leukemic cell survival and/or proliferation. However, it remains unclear how the dynamics of the leukemic cell-niche interaction are regulated. Using a genome-wide CRISPR screen, we discovered that canonical BRG1/BRM-associated factor (cBAF), a variant of the switch/sucrose nonfermenting chromatin remodeling complex, regulates the migratory response of human T-cell acute lymphoblastic leukemia (T-ALL) cells to a niche factor CXCL12. Mechanistically, cBAF maintains chromatin accessibility and allows RUNX1 to bind to CXCR4 enhancer regions. cBAF inhibition evicts RUNX1 from the genome, resulting in CXCR4 downregulation and impaired migration activity. In addition, cBAF maintains chromatin accessibility preferentially at RUNX1 binding sites, ensuring RUNX1 binding at these sites, and is required for expression of RUNX1-regulated genes, such as CDK6; therefore, cBAF inhibition negatively impacts cell proliferation and profoundly induces apoptosis. This anticancer effect was also confirmed using T-ALL xenograft models, suggesting cBAF as a promising therapeutic target. Thus, we provide novel evidence that cBAF regulates the RUNX1-driven leukemic program and governs migration activity toward CXCL12 and cell-autonomous growth in human T-ALL.

Nardilysin determines hematopoietic stem cell fitness by regulating protein synthesis.

Nardilysin (NRDC) is a multifunctional protein required for maintaining homeostasis in various cellular and tissue contexts. However, its role in hematopoietic stem cells (HSCs) remains unclear. Here, through the conditional deletion of NRDC in hematopoietic cells, we demonstrate that NRDC is required for HSCs expansion in vitro and the reconstitution of hematopoiesis in vivo after transplantation. We found NRDC-deficient HSCs lose their self-renewal ability and display a preferential bias to myeloid differentiation in response to replication stress. Transcriptome data analysis revealed the upregulation of heat shock response-related genes in NRDC-deficient HSCs. Additionally, we observed increased protein synthesis in cultured NRDC-deficient HSCs. Thus, loss of NRDC may cause the inability to control protein synthesis in response to replication induced protein stress, leading to the impaired HSC self-renewal ability. This highlights a novel model of action of NRDC specifically in HSCs.

Direct inhibition of human APOBEC3 deaminases by HIV-1 Vif independent of the proteolysis pathway.

HIV-1 Vif is known to counteract the antiviral activity of human apolipoprotein B mRNA-editing catalytic polypeptide-like (A3), a cytidine deaminase, in various ways. However, the precise mechanism behind this interaction has remained elusive. Within infected cells, Vif forms a complex called VßBCC, comprising CBFß and the components of E3 ubiquitin ligase, Elongin B, Elongin C, and Cullin5. Together with the ubiquitin-conjugating enzyme, VßBCC induces ubiquitination-mediated proteasomal degradation of A3. However, Vif exhibits additional counteractive effects. In this study, we elucidate that VßBCC inhibits deamination by A3G, A3F, and A3B independently of proteasomal degradation. Surprisingly, we discovered that this inhibition for A3G is directly attributed to the interaction between VßBCC and the C-terminal domain of A3G. Previously, it was believed that Vif did not interact with the C-terminal domain. Our findings suggest that inhibiting the interaction between VßBCC and the C-terminal domain, as well as the N-terminal domain known to be targeted for ubiquitination, of A3G may be needed to prevent counteraction by Vif.