Validation of the 2022 European LeukemiaNet risk stratification for acute myeloid leukemia.

This study aimed to validate the 2022 European LeukemiaNet (ELN) risk stratification for acute myeloid leukemia (AML). A total of 624 newly diagnosed AML patients from 1998 to 2014 were included in the analysis. Genetic profiling was conducted using targeted deep sequencing of 45 genes based on recurrent driver mutations. In total, 134 (21.5%) patients had their risk classification reassessed according to the 2022 ELN risk stratification. Among those initially classified as having a favorable risk in 2017 (n = 218), 31 and 3 patients were reclassified as having intermediate risk or adverse risk, respectively. Among the three subgroups, the 2022 ELN favorable-risk group showed significantly longer survival outcomes than the other groups. Within the 2017 ELN intermediate-risk group (n = 298), 21 and 46 patients were reclassified as having favorable risk or adverse risk, respectively, and each group showed significant stratifications in survival outcomes. Some patients initially classified as having adverse risk in 2017 were reclassified into the intermediate-risk group (33 of 108 patients), but no prognostic improvements were observed in this group. A multivariable analysis identified the 2022 ELN risk stratification, age, and receiving allogeneic hematopoietic cell transplantation as significant prognostic factors for survival. The 2022 ELN risk stratification enables more precise decisions for proceeding with allogeneic hematopoietic cell transplantation for AML patients.

Prognostic analysis according to European LeukemiaNet 2022 risk stratification for elderly patients with acute myeloid leukemia treated with decitabine.

OBJECTIVES: This study aimed to evaluate the prognostic significance of the revised European LeukemiaNet (ELN)-2022 risk stratification model for 123 elderly acute myeloid leukemia (AML) patients treated with decitabine chemotherapy. RESULTS: Based on the ELN-2022 risk stratification, 15 (12.2%), 51 (41.5%), and 57 (46.3%) patients were classified as having favorable, intermediate, and high-risk AML, respectively. In comparison with the ELN-2017 risk stratification, the ELN-2022 risk stratification re-assigned 26 (21.1%) and three (2.4%) patients to the adverse and favorable risk groups, respectively. Survival analysis revealed distinctive overall survival (OS) outcomes among the ELN-2022 risk groups (6-month OS rate: 73.3%, 52.9%, and 47.7% for favorable, intermediate, and adverse risk, respectively; P = 0.101), with a parallel trend observed in the event-free survival (EFS) (6-month EFS rate: 73.3%, 52.9%, and 45.6% for favorable, intermediate, and adverse risk, respectively; P = 0.049). Notably, both OS and EFS in the favorable risk group were significantly superior in comparison to that of the adverse risk group (OS: P = 0.040, EFS: P = 0.030). Although the ELN-2022 C-index (0.559) was greater than the ELN-2017 C-index (0.539), the result was not statistically significant (P = 0.059). Based on the event net reclassification index, we consistently observed significant improvements in the ELN-2022 risk stratification for overall survival (0.21 at 6 months). CONCLUSION: In conclusion, the revised ELN-2022 risk stratification model may have improved the risk classification of elderly AML patients treated with hypomethylating agents compared to the ELN-2017 risk stratification model.

Exploring cellular immunotherapy platforms in multiple myeloma.

Despite major advances in therapeutic platforms, most patients with multiple myeloma (MM) eventually relapse and succumb to the disease. Among the novel therapeutic options developed over the past decade, genetically engineered T cells have a great deal of potential. Cellular immunotherapies, including chimeric antigen receptor (CAR) T cells, are rapidly becoming an effective therapeutic modality for MM. Marrow-infiltrating lymphocytes (MILs) derived from the bone marrow of patients with MM are a novel source of T cells for adoptive T-cell therapy, which robustly and specifically target myeloma cells. In this review, we examine the recent innovations in cellular immunotherapies, including the use of dendritic cells, and cellular tools based on MILs, natural killer (NK) cells, and CAR T cells, which hold promise for improving the efficacy and/or reducing the toxicity of treatment in patients with MM.

Risk stratification for early mortality in newly diagnosed acute promyelocytic leukemia: a multicenter, non-selected, retrospective cohort study.

Introduction: Despite the current effective treatments for acute promyelocytic leukemia (APL), early mortality (EM), defined as death within 30 days of presentation, is a major hurdle to long-term survival. Methods: We performed a multicenter retrospective study to evaluate the incidence and clinical characteristics of EM in patients with newly diagnosed APL and to develop a risk stratification model to predict EM. Results: We identified 313 eligible patients diagnosed between 2000 and 2021 from five academic hospitals. The median age was 50 years (range 19-94), and 250 (79.9%) patients were <65 years. Most patients (n=274, 87.5%) received their first dose of all-trans retinoic acid (ATRA) within 24 hours of presentation. EM occurred in 41 patients, with a cumulative incidence of 13.1%. The most common cause of EM was intracranial hemorrhage (n=22, 53.6%), and most EMs (31/41, 75.6%) occurred within the first seven days of APL presentation. In a multivariable analysis, we identified three independent factors predicting EM: age ≥65 years (HR, 2.56), white blood cell count ≥8.0 x 109/L (HR, 3.30), and ATRA administration >24 hours of presentation (HR, 2.95). Based on these factors, patients were stratified into three categories with a significantly increasing risk of EM: 4.1% for low risk (54.3%; no risk factors; HR 1), 18.5% for intermediate risk (34.5%; 1 factor; HR 4.81), and 40.5% for high risk (11.2%; 2-3 factors; HR 13.16). Discussion: The risk of EM is still not negligible in this era of ATRA-based therapies. Our risk model serves as a clinically useful tool to identify high-risk patients for EM who may be candidates for novel treatments and aggressive supportive strategies.

Prognostic Significance Of Sequential 18f-fdg Pet/Ct During Frontline Treatment Of Peripheral T Cell Lymphomas.

BACKGROUND/AIMS: The prognostic significance of 18F-fluorodeoxyglucose (FDG)-positron emission tomography-computed tomography (PET/CT) in peripheral T-cell lymphomas (PTCLs) are controversial. We explored the prognostic impact of sequential 18F-FDG PET/CT during frontline chemotherapy of patients with PTCLs. METHODS: In total, 143 patients with newly diagnosed PTCLs were included. Sequential 18F-FDG PET/CTs were performed at the time of diagnosis, during chemotherapy, and at the end of chemotherapy. The baseline total metabolic tumor volume (TMTV) was calculated using the the standard uptake value with a threshold method of 2.5. RESULTS: A baseline TMTV of 457.0 cm3 was used to categorize patients into high and low TMTV groups. Patients with a requirehigh TMTV had shorter progression-free survival (PFS) and overall survival (OS) than those with a low TMTV (PFS, 9.8 vs. 26.5 mo, p = 0.043; OS, 18.9 vs. 71.2 mo, p = 0.004). The interim 18F-FDG PET/CT response score was recorded as 1, 2-3, and 4-5 according to the Deauville criteria. The PFS and OS showed significant differences according to the interim 18F-FDG PET/CT response score (PFS, 120.7 vs. 34.1 vs. 5.1 mo, p < 0.001; OS, not reached vs. 61.1 mo vs. 12.1 mo, p < 0.001). CONCLUSION: The interim PET/CT response based on visual assessment predicts disease progression and survival outcome in PTCLs. A high baseline TMTV is associated with a poor response to anthracycline-based chemotherapy in PTCLs. However, TMTV was not an independent predictor for PFS in the multivariate analysis.

Effect of BCR::ABL1 transcript type and droplet digital polymerase chain reaction on successful treatment-free remission in chronic myeloid leukemia patients who discontinued tyrosine kinase inhibitor.

Background: Droplet digital polymerase chain reaction (ddPCR) is an exact method of measurement. Objectives: We conducted this study to identify the prognostic factors for successful treatment-free remission in patients with chronic-phase chronic myeloid leukemia who discontinued tyrosine kinase inhibitors (TKIs). We also aimed to validate ddPCR for predicting molecular relapse. Design: This is a prospective, multicenter study. Methods: We enrolled patients treated with TKIs for at least 3 years with a confirmed sustained deep molecular response (DMR) for at least 1 year. TKI was re-administered in patients who experienced the loss of major molecular response (MMR). Results: A total of 66 patients from five institutions in South Korea were enrolled. During a median follow-up period of 16.5 months, 29/66 (43.9%) patients experienced molecular relapse; the probability of molecular relapse-free survival (RFS) at 6 or 12 months after TKI discontinuation was 65.6% or 57.8%, respectively, with most molecular relapses occurring within the first 7 months. All patients who lost MMR were re-treated with TKI, and all re-achieved MMR at a median of 2.8 months. E14a2 transcript type (p = 0.005) and longer DMR duration (⩾48 months) prior to TKI discontinuation (p = 0.002) were associated with prolonged molecular RFS and with sustained DMR. Patients with both e13a2 transcript type and detectable BCR::ABL1 (⩾MR5.0) by ddPCR at the time of TKI discontinuation showed shorter duration of molecular RFS (p = 0.015). Conclusion: Our data suggest that transcript type and BCR::ABL1 transcript levels on ddPCR should be taken into consideration when deciding whether to discontinue TKI therapy.

Identification of Cell Type-Specific Effects of DNMT3A Mutations on Relapse in Acute Myeloid Leukemia.

Acute myeloid leukemia (AML) is a heterogeneous disease caused by distinctive mutations in individual patients; therefore, each patient may display different cell-type compositions. Although most patients with AML achieve complete remission (CR) through intensive chemotherapy, the likelihood of relapse remains high. Several studies have attempted to characterize the genetic and cellular heterogeneity of AML; however, our understanding of the cellular heterogeneity of AML remains limited. In this study, we performed single-cell RNA sequencing (scRNAseq) of bone marrow-derived mononuclear cells obtained from same patients at different AML stages (diagnosis, CR, and relapse). We found that hematopoietic stem cells (HSCs) at diagnosis were abnormal compared to normal HSCs. By improving the detection of the DNMT3A R882 mutation with targeted scRNAseq, we identified that DNMT3A-mutant cells that mainly remained were granulocyte-monocyte progenitors (GMPs) or lymphoid-primed multipotential progenitors (LMPPs) from CR to relapse and that DNMT3A-mutant cells have gene signatures related to AML and leukemic cells. Copy number variation analysis at the single-cell level indicated that the cell type that possesses DNMT3A mutations is an important factor in AML relapse and that GMP and LMPP cells can affect relapse in patients with AML. This study advances our understanding of the role of DNMT3A in AML relapse and our approach can be applied to predict treatment outcomes.

Rituximab plus multiagent chemotherapy for newly diagnosed CD20-positive acute lymphoblastic leukemia: a prospective phase II study.

BACKGROUND/AIMS: We performed a prospective study to determine the efficacy and safety of rituximab including chemotherapy in CD20-positive acute lymphoblastic leukemia (ALL). METHODS: Patients with newly diagnosed ALL, aged ≥ 15 years, were eligible for the study if their leukemic blast cells in bone marrow expressed CD20 ≥ 20% at the time of diagnosis. Patients received multiagent chemotherapy with rituximab. After achieving complete remission (CR), patients received five cycles of consolidation with concomitant rituximab. Rituximab was administered monthly from day 90 of transplantation for patients who received allogeneic hematopoietic cell transplantation. RESULTS: In patients with Philadelphia (Ph)-negative ALL, 39 of 41 achieved CR (95.1%), the 2- and 4-year relapse-free survival (RFS) rates were 50.4% and 35.7%, and the 2- and 4-year overall survival (OS) rates were 51.5% and 43.2%, respectively. In the group with Ph-positive ALL, all 32 patients achieved CR, the 2- and 4-year RFS rates were 60.7% and 52.1%, and the 2- and 4-year OS rates were 73.3% and 52.3%, respectively. In the Ph-negative ALL group, patients with higher CD20 positivity experienced more favorable RFS (p < 0.001) and OS (p = 0.06) than those with lower CD20 positivity. Patients who received ≥ 2 cycles of rituximab after transplantation had significantly improved RFS (hazard ratio [HR], 0.31; p = 0.049) and OS (HR, 0.29; p = 0.021) compared with those who received < 2 cycles. CONCLUSION: The addition of rituximab to conventional chemotherapy for CD20-positive ALL is effective and tolerable (Clinicaltrials. gov NCT01429610).

The prognostic impact of reduced variant burden in elderly patients with acute myeloid leukemia treated with decitabine.

BACKGROUND/AIMS: We evaluated the role of next-generation sequencing (NGS)-based disease monitoring for elderly patients diagnosed with acute myeloid leukemia (AML) who received decitabine therapy. METHODS: A total of 123 patients aged > 65 years with AML who received decitabine were eligible. We analyzed the dynamics of variant allele frequency (VAF) in 49 available follow-up samples after the fourth cycle of decitabine. The 58.6% VAF clearance (Δ, [VAF at diagnosis - VAF at follow-up] × 100 / VAF at diagnosis) was the optimal cut-off for predicting overall survival (OS). RESULTS: The overall response rate was 34.1% (eight patients with complete remission [CR], six of CR with incomplete hematologic recovery, 22 with partial responses, and six with morphologic leukemia-free status). Responders (n = 42) had significantly better OS compared with non-responders (n = 42) (median, 15.3 months vs. 6.5 months; p < 0.001). Of the 49 patients available for follow-up targeted NGS analysis, 44 had trackable gene mutations. The median OS of patients with ΔVAF ≥ 58.6% (n=24) was significantly better than that of patients with ΔVAF < 58.6% (n = 19) (20.5 months vs. 9.8 months, p = 0.010). Moreover, responders with ΔVAF ≥ 58.6% (n = 20) had a significantly longer median OS compared with responders with VAF < 58.6% (n = 11) (22.5 months vs. 9.8 months, p = 0.004). CONCLUSION: This study suggested that combining ΔVAF ≥ 58.6%, a molecular response, with morphologic and hematologic responses can more accurately predict OS in elderly AML patients after decitabine therapy.

Clonal hematopoiesis in the donor does not adversely affect long-term outcomes following allogeneic hematopoietic stem cell transplantation: result from a 13-year follow-up.

Donor clonal hematopoiesis may be transferred to the recipient through allogeneic hematopoietic stem cell transplantation (HSCT), but the potential for adverse long-term impact on transplant outcomes remains unknown. A total of 744 samples from 372 recipients who received HSCT and the corresponding donors were included. Bar-coded error-corrected sequencing using a modified molecular inversion probe capture protocol was performed, which targeted 33 genes covering mutations involved in clonal hematopoiesis with indeterminate potential (CHIP) and other acute myeloid leukemia-related mutations. A total of 30 mutations were detected from 25 donors (6.7%): the most frequently mutated gene was TET2 (n=7, 28%), followed by DNMT3A (n=4, 16%), SMC3 (n=3, 12%) and SF3B1 (n=3, 12%). With a median follow-up duration of 13 years among survivors, the presence of CHIP in the donor was not associated with recipient overall survival (P=0.969), relapse incidence (P=0.600) or non-relapse mortality (P=0.570). Donor CHIP did not impair neutrophil (P=0.460) or platelet (P=0.250) engraftment, the rates of acute (P=0.490), or chronic graft-versus-host disease (P=0.220). No significant difference was noted for secondary malignancy following HSCT between the two groups. The present study suggests that the presence of CHIP in allogeneic stem donors does not adversely affect transplant outcomes after HSCT. Accordingly, further study is warranted to reach a clearer conclusion on whether molecular profiling to determine the presence of CHIP mutations is necessary for the pretransplant evaluation of donors prior to stem cell donation.

Clinical Experience of Allogeneic Hematopoietic Stem Cell Transplantation in Elderly Patients Aged 60 Years and Older in South Korea.

PURPOSE: The purpose of this study is to share our outcomes and experiences on allogeneic hematopoietic stem cell transplantation (HSCT) in elderly patients aged 60 years and older with myelodysplastic syndrome (MDS) or acute myeloid leukemia (AML) in South Korea, and to compare them with other studies. MATERIALS AND METHODS: We analyzed the clinical outcomes of 116 patients with AML or MDS aged 60 years and older who underwent allogeneic HSCT. We also analyzed which pretreatment factors affect the overall survival (OS) after allogeneic HSCT. RESULTS: Neutrophil and platelet engraftment were achieved at median day +11 [interquartile range (IQR) 10-15] and +14 (IQR 11-19), respectively. A complete donor chimerism was confirmed in 65 (56.0%) patients at 3 weeks and in 63 (54.3%) patients at 3 months after HSCT. The estimated incidence of grade II-IV acute graft-versus-host disease (GVHD) at day 100 was 13.7%. The estimated incidence of chronic GVHD at 2 years was 38.8%. Within a median follow-up of 14 months after HSCT, OS was 64% at 1 year and 55% at 2 years, and non-relapse mortality (NRM) was 20% at 1 year and 28% at 2 years. Multivariate analysis revealed that male sex and Hematopoietic Cell Transplantation-Specific Comorbidity Index ≥3 were associated with poor OS. CONCLUSION: This study showed that allogeneic HSCT in elderly adults aged 60 and older can be performed with successful engraftment and acceptable NRM and OS are expected given the generally known survival of patients with higher risk MDS and poor risk AML.

Clinical Significance of bZIP In-Frame CEBPA-Mutated Normal Karyotype Acute Myeloid Leukemia.

PURPOSE: We evaluated the characteristics of CCAAT/enhancer-binding protein α (CEBPA) mutations and the significance of a basic leucine zipper in-frame mutation (bZIPin-f) of CEBPA in patients with acute myeloid leukemia with a normal karyotype. Materials and Methods: Based on updated knowledge of CEBPA mutations, we conducted next-generation sequencing analyses in a previously established real-world cohort. RESULTS: Among 78 of a total of 395 patients (19.7%), 50 had bZIPin-f CEBPA, and 28 had non-bZIPin-f CEBPA. In the multivariate analysis, patients with NPM1mut, those with bZIPin-f CEBPA, and those who underwent allogeneic hematopoietic cell transplantation (allo-HCT) had favorable overall survival (OS), but FLT3-ITDmut was a poor prognostic indicator. For relapse-free survival (RFS) and cumulative incidence of relapse, bZIPin-f CEBPA, and allo-HCT were associated with favorable outcomes; FLT3-ITDpos was associated with worse outcomes. In the CEBPA double-mutated group (CEBPAdm), bZIPin-f CEBPA was associated with superior outcomes in terms of OS (p=0.007) and RFS (p=0.007) compared with non-bZIPin-f CEBPA. Of 50 patients with bZIPin-f CEBPA, 36 patients had at least one mutation. When grouped by the presence of mutations in chromatic/DNA modifiers (C), cohesion complex (C), and splicing genes (S) (CCS mutations), CCS-mutated bZIPin-f CEBPA was associated with poor OS (p=0.044; hazard ratio [HR], 2.419) and a trend in inferior RFS (p=0.186; HR, 1.838). CONCLUSION: Only bZIPin-f CEBPA was associated with favorable outcomes in patients with CEBPAdm. However, some mutations accompanying bZIPin-f CEBPA showed inferior OS; thus, further studies with larger numbers of patients are required for clear conclusions of the significance of bZIPin-f CEBPA.

Expanded natural killer cells potentiate the antimyeloma activity of daratumumab, lenalidomide, and dexamethasone in a myeloma xenograft model.

The development of new treatment agents in recent decades has significantly improved the survival of patients with multiple myeloma (MM). Nonetheless, MM remains an incurable disease; therefore, novel combination therapies are required. Natural killer (NK) cells are one of the safest immunotherapeutic options. In this study, we found that the anti-myeloma activity of expanded NK cells (eNKs) was improved by daratumumab, lenalidomide, and dexamethasone (DRd) in an MM xenograft mouse model. NK cells expanded from peripheral blood mononuclear cells collected from MM patients were highly cytotoxic against DRd pretreated tumor cells in vitro. To mimic the clinical protocol, a human MM xenograft model was developed using human RPMI8226-RFP-FLuc cells in NOD/SCID IL-2Rγnull (NSG) mice. MM bearing mice were randomly divided into six groups: no treatment, eNK, Rd, Rd + eNKs, DRd, and DRd + eNKs. DRd significantly enhanced the cytotoxicity of eNKs by upregulating NK cell activation ligands and effector function. DRd in combination with eNKs significantly reduced the serum M-protein level and prolonged mouse survival. In addition, DRd significantly increased the persistence of eNK and homing to MM sites. These results show that the anti-myeloma activity of ex vivo-expanded and activated NK cells is augmented by the immunomodulatory effect of DRd in MM-bearing mice, suggesting the therapeutic potential of this combination for MM patients.

Next-generation sequencing-based analysis to assess the pattern of relapse in patients with Philadelphia-positive acute lymphoblastic leukemia.

In this study, we performed serial monitoring using targeted DNA sequencing to identify genetic alterations in adults with Philadelphia-positive acute lymphoblastic leukemia (Ph-ALL). Deep sequencing was performed by targeting the coding regions of 45 genes with recurrent driver mutations and 1129 single nucleotide polymorphism sites. Of the 43 patients that we examined, at least one case of genetic alterations was detected in 38 (88%) of the 43 patients at diagnosis (somatic mutations in 10 patients [23%] and copy number aberrations [CNA] in 36 patients [84%]). The most frequently detected CNA lesions were in IKZF1 (n = 25, 58%) and the most frequently mutated gene was SETD2 (n = 5). At least one genetic abnormality (loss, gain, or persistence) was observed in all the samples obtained at relapse that were available for analysis (n = 15), compared with the samples obtained at diagnosis (disappearance of any previously detected genetic alterations: 11 patients [73%]; new genetic abnormalities: nine patients [60%]; and persistent genetic abnormalities: eight patients [53%]]. The most frequently deleted lesions were in IKZF1 (n = 9, 60%), and the most frequently mutated gene was ABL1 (eight patients, 53%). Our data indicate that leukemic progression may be associated with complex genetic alterations in Ph-ALL during the course of treatment.

Allogeneic hematopoietic cell transplantation can overcome the adverse prognosis indicated by secondary-type mutations in de novo acute myeloid leukemia.

Secondary-type mutations (STMs), namely SRSF2, SF3B1, U2AF1, ZRSR2, ASXL1, EZH2, BCOR, and STAG2, are more frequently detected in secondary acute myeloid leukemia (AML) than in de novo AML. Whether de novo AML with STMs should be differently managed is, however, unclear. In 394 patients diagnosed with de novo AML who had a normal karyotype, the genetic profiling via targeted deep sequencing of 45 genes revealed 59 patients carrying STMs (STM+). The STM+ group showed shorter overall survival (OS) than the STM- group (5-year OS, 15.3 vs. 31.0%) (hazard ratio [HR]: 1.975, 95% confidence interval [CI]: 1.446-2.699, p < 0.001). Among the 40 STM+ patients who achieved CR, those who received allogeneic HCT (n = 15) showed better OS (5-year OS, 40.0 vs. 12.0%) (HR: 0.423, 95% CI: 0.184-0.975, p = 0.043) and relapse-free survival (5-year, 40.0 vs. 8.0%) (HR: 0.438, 95% CI: 0.189-1.015, p = 0.054) than those who received consolidation chemotherapy only. The cumulative incidence of relapse was lower in the patients who received allogeneic HCT (5-year, 33.3 vs. 60.0%) (HR: 0.288, 95% CI: 0.111-0.746, p = 0.011), and non-relapse mortality was similar between the two groups (p = 0.935). In conclusion, STM is an independent prognostic factor for adverse outcomes in AML that can be overcome by allogeneic HCT.

Results of Multicenter Phase II Study With Imatinib Mesylate in Allogeneic Recipients With Steroid-Refractory Chronic GVHD.

In this multicenter phase II study, we evaluated the safety and efficacy of imatinib in patients with steroid-resistant chronic graft-versus-host disease (cGVHD) and evaluated the quality of life (QOL) of the enrolled patients using the Short Form 36 (SF-36) health survey questionnaire. Thirty-six patients who were diagnosed with steroid-refractory cGVHD and treated with imatinib between March 2013 and February 2019 received 100 mg/day of imatinib for 2 weeks. Depending on the patient's condition and investigator's decision, the imatinib dose was allowed to be increased by 100 mg every 2 weeks up to 400 mg/day. Patients who achieved stable disease (SD), partial remission (PR), and complete remission (CR) at 3-month response evaluations continued imatinib for up to 6 months. The majority of the patients had multi-organ cGVHD, with skin (63.9%), lungs (44.4%), mouth (38.9%), and eyes (38.9%) as the most common sites. The overall response rate was 58.3%, including 3 and 18 patients with CR and PR, respectively, and an overall decline in National Institutes of Health (NIH) severity scores was observed at study completion in the absence of significant adverse effects. The overall response rates were 70.5%, 66.7%, 34.8%, and 25% in patients with gastrointestinal, liver, skin, and lung cGVHD, respectively. Factors representing emotional well-being were significantly improved based on the patient-reported QOL evaluation using SF-36. The effect of imatinib on steroid tapering, which was notable in responders, was also present in 50% of those who achieved SD without worsening cGVHD. Imatinib exhibited therapeutic efficacy in steroid-refractory and steroid-dependent cGVHD with tolerable toxicity.Clinical Trial Registration: KCT0006785.

Genetic changes during leukemic transformation to secondary acute myeloid leukemia from myeloproliferative neoplasms.

Leukemic transformation (LT) is the main cause of death for patients with myeloproliferative neoplasms (MPNs). To study genetic changes associated with the LT, we performed targeted sequencing in 26 MPN patients including 21 with paired samples. We observed that, besides three driver genes, IDH2 (19%) and ASXL1 (14%) were also frequently mutated at MPN diagnosis. Although variant allele frequencies (VAFs) of mutations in DNA methylation and spliceosome did not expand during LT, they were enriched in patients with LT (the LT group). At follow-up, we also observed acquisition of mutations, mostly in the LT group. When considering dynamics of VAF from diagnosis to follow-up, VAFs in the LT group expanded (median VAF, 36.7-43.7%, p = 0.045). In contrast, mutations in patients with no clinical progression was stable (median VAF, 36.3-35.7%, p = 0.739). Overall, the present study demonstrates genetic changes during LT and provides the potential for prognostic application.

FLT3 mutations in acute myeloid leukemia: a review focusing on clinically applicable drugs.

FMS-like tyrosine kinase 3 (FLT3) mutations, the most frequently detected genetic aberrations in patients with acute myeloid leukemia (AML), are identified in approximately 30% of patients with newly diagnosed AML and are more common in patients with normal karyotypes. Since the discovery of FLT3 mutations in AML, clinical trials have been actively conducted in patients with FLT3 mutated AML, and FLT3 inhibitors have been introduced into clinical practice. The current standard treatment for patients with newly diagnosed FLT3-mutated AML is 7+3 induction chemotherapy combined with midostaurin. Additionally, gilteritinib is more effective than salvage chemotherapy for relapsed or refractory FLT3-mutated AML. Ongoing trials are expected to provide additional treatment options depending on the disease state and patient vulnerability. This review summarizes information on clinically available FLT3 inhibitors for the management of AML with FLT3 mutations.

Novel IL-15 dendritic cells have a potent immunomodulatory effect in immunotherapy of multiple myeloma.

Dendritic cells (DCs) are the most potent antigen-presenting cells, and have thus been used in clinical cancer vaccines. However, the effects of DC vaccines are still limited, leading researchers to explore novel ways to make them effective. In this study, we investigated whether human monocyte-derived DCs generated via the addition of interleukin 15 (IL-15) had a higher capacity to induce antigen-specific T cells compared to conventional DCs. We isolated CD14+ monocytes from peripheral blood from multiple myeloma (MM) patients, and induced immature DCs with granulocyte-macrophage colony-stimulating factor (GM-CSF) and IL-4 in the presence or absence of IL-15 for 4-6 days. Then we generated mature DCs (mDCs) with lipopolysaccharide for another 2 days [IL-15 mDCs (6 days), IL-15 mDCs (8 days), and conventional mDCs (8 days)]. IL-15 mDCs (6 days) showed higher expression of MHC I and II, CD40, CD86, and CCR7, and the secretion of IFN-γ was significantly higher compared to conventional mDCs. IL-15 mDCs (6 days) showed superior polarization of naïve T cells toward Th1 cells and a higher proportion of activated T cells, cytokine-induced killer (CIK) cells, and natural killer (NK) cells for inducing strong cytotoxicity against myeloma cells, and lower proportion of regulatory T cells compared to conventional mDCs. These data imply that novel multipotent mDCs generated by the addition of IL-15, which can be cultivated in 6 days, resulted in outstanding activation of T cells, CIK cells and NK cells, and may facilitate cellular immunotherapy for cancer patients.

FAM167A is a key molecule to induce BCR-ABL-independent TKI resistance in CML via noncanonical NF-κB signaling activation.

BACKGROUND: BCR-ABL-independent drug resistance is a barrier to curative treatment of chronic myeloid leukemia (CML). However, the molecular pathways underlying BCR-ABL-independent tyrosine kinase inhibitor (TKI) resistance remain unclear. METHODS: In silico bioinformatic analysis was performed to identify the most active transcription factor and its inducer that contribute to BCR-ABL-independent TKI resistance. Tandem mass spectrometry analysis was performed to identify the receptor for the noncanonical NF-κB activator FAM167A. In vitro and in vivo mouse experiments revealed detailed molecular insights into the functional role of the FAM167A-desmoglein-1 (DSG1) axis in BCL-ABL-independent TKI resistance. CML cells derived from CML patients were analyzed using quantitative reverse transcription PCR and flow cytometry. RESULTS: We found that NF-κB had the greatest effect on differential gene expression of BCR-ABL-independent TKI-resistant CML cells. Moreover, we found that the previously uncharacterized protein FAM167A activates the noncanonical NF-κB pathway and induces BCR-ABL-independent TKI resistance. Molecular analyses revealed that FAM167A activates the noncanonical NF-κB pathway by binding to the cell adhesion protein DSG1 to upregulate NF-κB-inducing kinase (NIK) by blocking its ubiquitination. Neutralization of FAM167A in a mouse tumor model reduced noncanonical NF-κB activity and restored sensitivity of cells to TKIs. Furthermore, FAM167A and surface DSG1 levels were highly upregulated in CD34+ CML cells from patients with BCR-ABL-independent TKI-resistant disease. CONCLUSIONS: These results reveal that FAM167A acts as an essential factor for BCR-ABL-independent TKI resistance in CML by activating the noncanonical NF-κB pathway. In addition, FAM167A may serve as an important target and biomarker for BCR-ABL-independent TKI resistance.