Tyrosine kinase inhibitors are recommended as maintenance therapy following allogeneic stem cell transplantation (HSCT) for Philadelphia chromosome-positive (Ph+) acute lymphoblastic leukemia (ALL), but optimal medication, dose, and duration remain a subject of ongoing study. We provide the final analysis of a prospective randomized trial comparing prophylactic and minimal residual disease (MRD)-triggered imatinib maintenance. The two patient cohorts did not differ significantly in terms of cumulative incidence of relapse (CIR; 14% vs. 18%), non-relapse mortality (NRM; 12% vs. 11%), leukemia-free survival (LFS) 64% vs. 69%, and overall survival (OS) at 10 years (68% vs. 71%). Endpoints were assessed every 6 weeks within the trial from 4 weeks after SCT until EOS at week 55 and after that according to local standards. In summary, this provides a framework for MRD-based treatment of patients for maintenance after HSCT with excellent long-term outcome after 10 years in both groups.

Vamotinib (PF-114) is a 3rd -generation, ATP-competitive oral tyrosine kinase inhibitor (TKI) active against wild-type and mutated BCR::ABL1 isoforms including BCR::ABL1T315I. We present final results of a phase-1 vamotinib dose-escalation study to identify maximum tolerated dose (MTD) and dose-limiting toxicity (DLT) followed by expansion cohorts. 51 subjects with chronic myeloid leukaemia (CML) failing ≥ 1 2nd generation TKI or with BCR::ABL1T315I were enrolled. Subjects received vamotinib, 50–750 mg/d, continuously. Median exposure was 6 months (range, < 1–52 months). Median CML duration pre-study was 10 years (range, < 1–23 years). 27 subjects received ≥ 3 prior TKIs and 16 had BCR::ABL1T315I. The MTD was 600 mg with the Grade-3 psoriasis-like skin toxicity as the DLT. There were no vascular occlusive events nor deviations of ankle-brachial index. Complete haematologic response (CHR) was achieved in 14 of 30 subjects, major cytogenetic response (MCyR) in 14 of 44 subjects, complete cytogenetic response (CCyR) in 10 of 50 and major molecular response (MMR) in 7 of 51 subjects who did not have a CHR, MCyR, CCyR or MMR at enrollment. The best safety/efficacy dose was 300 mg with MCyR achieved in 6 of 7 subjects, CCyR in 5 of 9 and MMR in 4 of 9 subjects who did not have a MCyR, CCyR or MMR at enrollment. 5 of 16 subjects with BCR::ABL1T315I responded including 3 achieving a CHR, 3, a MCyR, and 1,a CCyR. 2 of 5 subjects failing ponatinib achieved a CHR. Vamotinib dose for further phase-3 study is 300 mg/d.

Imatinib (IMA) plus chemotherapy followed by allogeneic hematopoietic cell transplantation (HCT) is established treatment for Philadelphia chromosome positive (Ph+) acute lymphoblastic leukemia (ALL). We investigated the use of dasatinib (DASA) combined with intensive chemotherapy in ALL (18-55 years) first-line in a prospective, multicenter phase II trial by the GMALL study group. 140 mg DASA QD was used with a pediatric-based induction and consolidation chemotherapy according to GMALL 07/2003 protocol with recommended consecutive HCT. Nineteen of 20 planned patients were enrolled in 12 centers. The hematologic CR rate after induction was 79% with an overall MRD negativity rate of 62.5%. Six patients died during induction and two discontinued therapy. This regimen achieved deep molecular responses but was associated with a higher than expected early mortality (21%) and was stopped prematurely due to toxicities. The GMALL therefore adopted a combination of low intensity chemotherapy plus IMA as its current induction regimen.

Experts from the European Leukemia Net (ELN) working group for adult acute lymphoblastic leukemia have identified an unmet need for guidance regarding management of adult ALL from diagnosis to aftercare. The group has previously summarized their recommendations regarding diagnostic approaches, prognostic factors and assessment of ALL (cross-reference). The current recommendation summarizes clinical management. It covers treatment approaches including the use of new immunotherapies, application of MRD for treatment decisions, management of specific subgroups and challenging treatment situations as well as late effects and supportive care. The recommendation provides guidance for physicians caring for adult ALL patients which has to be complemented by regional expertise preferably provided by national academic study groups.

Experts from the European Leukemia Net (ELN) working group for adult acute lymphoblastic leukemia have identifi ed an unmet need for guidance regarding management of adult acute lymphoblastic leukemia (ALL) from diagnosis to aftercare. The group has previously summarized their recommendations regarding diagnostic approaches, prognostic factors, and assessment of ALL. The current recommendation summarizes clinical management. It covers treatment approaches, including the use of new immunotherapies, application of minimal residual disease for treatment decisions, management of speci fi c subgroups, and challenging treatment situations as well as late effects and supportive care. The recommendation provides guidance for physicians caring for adult patients with ALL which has to be complemented by regional expertise preferably provided by national academic study groups.

Working groups of the European Leukemia Net (ELN) have published several important consensus guidelines. Acute lymphoblastic leukemia (ALL) has many different clinical and biological subgroups and the knowledge on disease biology and therapeutic options is increasing exponentially. The European Working Group for Adult ALL has therefore summarized the current state of the art and provided comprehensive consensus recommendations for diagnostic approaches, biologic and clinical characterization, prognostic factors and risk stratification as well as definitions of endpoints and outcomes. Aspects of treatment, management of subgroups and specific situations, aftercare and supportive care are covered in a separate publication. The present recommendation intends to provide guidance for the initial management of adult ALL patients and to define principles as a basis for future collaborative research.

The safety and efficacy of sabatolimab, a novel immunotherapy targeting T-cell immunoglobulin domain and mucin domain-3 (TIM-3), was assessed in combination with hypomethylating agents (HMAs) in patients with HMA-naive revised International Prognostic System Score (IPSS-R) high- or very high-risk myelodysplastic syndromes (HR/vHR-MDS) or chronic myelomonocytic leukemia (CMML). Sabatolimab + HMA had a safety profile similar to that reported for HMA alone and demonstrated durable clinical responses in patients with HR/vHR-MDS. These results support the ongoing evaluation of sabatolimab-based combination therapy in MDS, CMML, and acute myeloid leukemia.

Asciminib is approved for patients with Philadelphia chromosome–positive chronic-phase chronic myeloid leukemia (CML-CP) who received ≥2 prior tyrosine kinase inhibitors or have the T315I mutation. We report updated results of a phase 1, open-label, nonrandomized trial (NCT02081378) assessing the safety, tolerability, and antileukemic activity of asciminib monotherapy 10–200 mg once or twice daily in 115 patients with CML-CP without T315I (data cutoff: January 6, 2021). After ≈4-year median exposure, 69.6% of patients remained on asciminib. The most common grade ≥3 adverse events (AEs) included increased pancreatic enzymes (22.6%), thrombocytopenia (13.9%), hypertension (13.0%), and neutropenia (12.2%); all-grade AEs (mostly grade 1/2) included musculoskeletal pain (59.1%), upper respiratory tract infection (41.7%), and fatigue (40.9%). Clinical pancreatitis and arterial occlusive events (AOEs) occurred in 7.0% and 8.7%, respectively. Most AEs occurred during year 1; the subsequent likelihood of new events, including AOEs, was low. By data cutoff, among patients without the indicated response at baseline, 61.3% achieved BCR::ABL1 ≤ 1%, 61.6% achieved ≤0.1% (major molecular response [MMR]), and 33.7% achieved ≤0.01% on the International Scale. MMR was maintained in 48/53 patients who achieved it and 19/20 who were in MMR at screening, supporting the long-term safety and efficacy of asciminib in this population.

BCL11A/EVI9, a zinc-finger protein primarily expressed in brain and hematopoietic cells, plays a central role in lymphocyte development, gamma-globin suppression, spinal neuron development, sensory innervation, neuronal polarity, migration, and is associated with microcephaly and dysregulated brain-related genes, offering therapeutic potential for sickle cell disease. The function of the transcriptional regulator is intricately linked to its structural organization, which determines its ability to interact with specific DNA sequences and modulate gene expression. BCL11A boasts multiple domains, including six C2H2 zinc fingers, a C2HC zinc finger, a NuRD-interacting domain, an acidic domain, and a proline-rich domain. In the present study, we delve into the intricate structure and function of the zinc finger domains located in the BCL11A gene, which plays a crucial role in regulating the expression of gamma-globin gene. Specifically, three C2H2-type zinc finger domains, Znf4, Znf5, and Znf6, within BCL11A, are known to bind to DNA. Znf4 and Znf5 demonstrate a significant interaction with the TGACCA motif in the gamma-globin −115 HPFH region sequence, contributing substantially to DNA binding specificity. Although Znf3 and Znf6 also interact with DNA, their contributions are comparatively minor. Employing CRISPR-Cas9 technology, targeted genomic deletions of Znf4 exhibit high efficiency, opening doors for further research. Edited CD34+ cells successfully differentiate into erythrocytes without impairments, underscoring CRISPR-Cas9’s suitability for studying gene functions in erythropoiesis. Furthermore, BCL11A knockdown via sgRNAs results in elevated gamma-globin expression, offering a promising therapeutic avenue for beta-hemoglobinopathies. HPLC analysis reveals a substantial increase in HbF levels, particularly upon Znf4 deletion, emphasizing BCL11A gene potential as a therapeutic target. These findings also highlight the connection between the function of BCL11A and its structural organization, which can be modulated, and this insight can potentially be extended to uncover its roles in various other domains.

Topic: 27. Thalassemias Background: The expression of β-like globin genes in humans is controlled during development, with fetal γ-globin genes replaced by adult β-globin genes after birth. Mutations in the β-globin gene can cause β-hemoglobinopathies such as sickle cell disease (SCD) and β-thalassemia. Elevated fetal hemoglobin (HbF) levels can mitigate the clinical severity of these diseases, and reactivating the expression of γ-globin genes is a promising treatment strategy. Disrupting the binding of the BCL11A transcriptional repressor complex to the γ-globin gene promoter provides a novel approach for inducing fetal hemoglobin. Aims: The clinical severity of SCD and β-thalassemia can be mitigated by elevated fetal hemoglobin (HbF) levels. Therefore, we aimed to induce the expression of γ-globin genes restart tge production of fetal hemoglobin by disrupting the binding of the BCL11A transcriptional repressor complex to the γ-globin gene promoter. Methods: Using in silico tools, molecular dynamics simulation, and homology modelling, the binding efficiency of zinc fingers (Znf) 4, 5, and 6 of BCL11A was predicted. CRISPR-Cas9 genome editing was used to delete Znf4 in K562 cell lines and adult mobilized CD34+ hematopoietic stem and progenitor cells (HSPCs). The effect of the deletion on γ-globin expression and survival was evaluated. Results: In comparison with the other zinc finger domains, deletion of Znf4 decreased the binding affinity of BCL11A by > 70-fold, resulting in a readily detectable increase in γ-globin expression with a preferential increase in G-gamma. Deletion of znf4 in mobilized CD34+ cells from patients with β-thalassemia major also results in an improved phenotype and likely a survival advantage for maturing erythroid cells after editing. Summary/Conclusion: Disrupting Znf4 of BCL11A or the TTGACCA motif can improve gene editing therapy strategies for β-hemoglobinopathies by disrupting the interaction between BCL11A and the γ-globin gene promoter. Our findings revealed that Znf4 is a suitable target for disrupting BCL11A-mediated hemoglobin switching and complete failure in protein-protein interactions with functional partners and the γ-globin gene promoter. Keywords: Hematopoietic stem cell, Hemoglobin, Thalassemia

Supplementary Figure 4 from Targeting the Oligomerization Domain of ETO Interferes with RUNX1/ETO Oncogenic Activity in t(8;21)-Positive Leukemic Cells

The T cells of the immune system can target tumors and clear solid cancers following tumor-infiltrating lymphocyte (TIL) therapy. We used combinatorial peptide libraries and a proteomic database to reveal the antigen specificities of persistent cancer-specific T cell receptors (TCRs) following successful TIL therapy for stage IV malignant melanoma. Remarkably, individual TCRs could target multiple different tumor types via the HLA A*02:01-restricted epitopes EAAGIGILTV, LLLGIGILVL, and NLSALGIFST from Melan A, BST2, and IMP2, respectively. Atomic structures of a TCR bound to all three antigens revealed the importance of the shared x-x-x-A/G-I/L-G-I-x-x-x recognition motif. Multi-epitope targeting allows individual T cells to attack cancer in several ways simultaneously. Such "multipronged"T cells exhibited superior recognition of cancer cells compared with conventional T cell recognition of individual epitopes, making them attractive candidates for the development of future immunotherapies.

The coronavirus disease-19 (COVID-19) pandemic promises to have lasting impacts on cancer clinical trials that could lead to faster patient access to new treatments. In this article, an international panel of oncology experts discusses the lasting impacts of the pandemic on oncology clinical trials and proposes solutions for clinical trial stakeholders, with the support of recent data on worldwide clinical trials collected by IQVIA. These lasting impacts and proposed solutions encompass three topic areas. Firstly, acceleration and implementation of new operational approaches to oncology trials with patient-centric, fully decentralized virtual approaches that include remote assessments via telemedicine and remote devices. Geographical differences in the uptake of remote technology, including telemedicine, are discussed in the article, focusing on the impact of the local adoption of new operational approaches. Secondly, innovative clinical trials. The pandemic has highlighted the need for new trial designs that accelerate research and limit risks and burden for patients while driving optimization of clinical trial objectives and endpoints, while testing is being minimized. Areas of considerations for clinical trial stakeholders are discussed in detail. In addition, the COVID-19 pandemic has exposed the underrepresentation of minority groups in clinical trials; the approach for oncology clinical trials to improve generalizability of efficacy and outcomes data is discussed. Thirdly, a new problem-focused collaborative framework between oncology trial stakeholders, including decision makers, to leverage and further accelerate the innovative approaches in clinical research developed during the COVID-19 pandemic. This could shorten timelines for patient access to new treatments by addressing the cultural and technological barriers to adopting new operational approaches and innovative clinical trials. The role of the different stakeholders is described, with the aim of making COVID-19 a catalyst for positive change in oncology clinical research and eventually in cancer care.

Patients within the WHO-subgroup of t(6;9)-positive acute myeloid leukemia (AML) differ from other AML subgroups as they are characterised by younger age and a grim prognosis. Leukemic transformation can often be attributed to single chromosomal aberrations encoding oncogenes, in the case of t(6;9)-AML to the fusion protein DEK-CAN (also called DEK-NUP214). As being a rare disease there is the urgent need for models of t(6;9)-AML. The only cell line derived from a t(6;9)-AML patient currently available is FKH1. By using phospho-proteomics on FKH1 cells, we found a strongly activated ABL1 kinase. Further investigation revealed the presence of ETV6-ABL1. This finding renders necessary to determine DEK-CAN- and ETV6-ABL1-related features when using FKH1. This can be done as ETV6-ABL1 activity in FKH1 is responsive to imatinib. Nevertheless, we provided evidence that both SFK and mTOR activation in FKH1 are DEK-CAN-related features as they were activated also in other t(6;9) and DEK-CAN-positive models. The activation of STAT5 previously shown to be strong in t(6;9)-AML and activated by DEK-CAN is regulated in FKH1 by both DEK-CAN and ETV6-ABL1. In conclusion, FKH1 cells still represent a model for t(6;9)-AML and could serve as model for ETV6-ABL1-positive AML if the presence of these leukemia-inducing oncogenes is adequately considered.Taken together, all our results provide clear evidence of novel and specific interdependencies between leukemia-inducing oncogenes and cancer signaling pathways which will influence the design of therapeutic strategies to better address the complexity of cancer signaling.

Clinical recommendations for AML classification and risk-stratification remain heavily reliant on cytogenetic findings at diagnosis, which are present in <50% of patients. Using comprehensive molecular profiling data from 3,653 patients we characterize and validate 16 molecular classes describing 100% of AML patients. Each class represents diverse biological AML subgroups, and is associated with distinct clinical presentation, likelihood of response to induction chemotherapy, risk of relapse and death over time. Secondary AML-2, emerges as the second largest class (24%), associates with high-risk disease, poor prognosis irrespective of flow MRD negativity, and derives significant benefit from transplantation. Guided by class membership we derive a 3-tier risk-stratification score that re-stratifies 26% of patients as compared to standard of care. This results in a unified framework for disease classification and risk-stratification in AML that relies on information from cytogenetics and 32 genes. Last, we develop an open-access patient-tailored clinical decision support tool.

The WHO classifies t(6;9)-positive acute myeloid leukemia (AML) as a subgroup of high-risk AML because of its clinical and biological peculiarities, such as young age and therapy resistance. t(6;9) encodes the DEK/NUP214 fusion oncoprotein that targets only a small subpopulation of bone marrow progenitors for leukemic transformation. This distinguishes DEK/NUP214 from other fusion oncoproteins, such as PML/RARα, RUNX1/ETO, or MLL/AF9, which have a broad target population they block differentiation and increase stem cell capacity. A common theme among most leukemogenic fusion proteins is their aberrant localization compared to their wild-type counterparts. Although the actual consequences are widely unknown, it seems to contribute to leukemogenesis most likely by a sequester of interaction partners. Thus, we applied a global approach to studying the consequences of the aberrant localization of t(6;9)-DEK/NUP214 for its interactome. This study aimed to disclose the role of localization of DEK/NUP214 and the related sequester of proteins interacting with DEK/NUP214 for the determination of the biology of t(6;9)-AML. Here we show the complexity of the biological consequences of the expression of DEK/NUP214 by an in-depth bioinformatic analysis of the interactome of DEK/NUP214 and its biologically dead mutants. DEK/NUP214’s interactome points to an essential role for aberrant RNA-regulation and aberrant regulation of apoptosis and leukocyte activation as a significant determinant of the phenotype of t(6;9)-AML. Taken together, we provide evidence that the interactome contributes to the aberrant biology of an oncoprotein, providing opportunities for developing novel targeted therapy approaches.

The phase 3 MIRROS (MDM2 antagonist Idasanutlin in Relapsed or Refractory acute myeloid leukemia [AML] for Overall Survival) trial (NCT02545283) evaluated the efficacy and safety of the small-molecule MDM2 antagonist idasanutlin plus cytarabine in patients with relapsed/refractory (R/R) AML. Adults (n = 447) with R/R AML whose disease relapsed or was refractory after ≤2 prior induction regimens as initial treatment or following salvage chemotherapy regimen, with Eastern Cooperative Oncology Group performance status ≤2 were enrolled regardless of TP53 mutation status and randomly assigned 2:1 to idasanutlin 300 mg or placebo orally twice daily plus cytarabine 1 g/m2 IV on days 1 to 5 of 28-day cycles. At primary analysis (cutoff, November 2019), 436 patients were enrolled, including 355 in the TP53 wild-type intention-to-treat (TP53WT-ITT) population. The primary endpoint, overall survival in the TP53WT-ITT population, was not met (median, 8.3 vs 9.1 months with idasanutlin-cytarabine vs placebo-cytarabine; stratified hazard ratio [HR], 1.08; 95% confidence interval [CI], 0.81-1.45; P = .58). The complete remission (CR) rate, a key secondary endpoint, was 20.3% vs 17.1% (odds ratio [OR], 1.23; 95% CI, 0.70-2.18). The overall response rate (ORR) was 38.8% vs 22.0% (OR, 2.25; 95% CI, 1.36-3.72). Common any-grade adverse events (≥10% incidence in any arm) were diarrhea (87.0% vs 32.9%), febrile neutropenia (52.8% vs 49.3%), and nausea (52.5% vs 31.5%). In summary, despite improved ORR, adding idasanutlin to cytarabine did not improve overall survival or CR rates in patients with R/R AML.