Complex karyotype in de novo acute myeloid leukemia: typical and atypical subtypes differ molecularly and clinically

Immune Escape of Acute Myeloid Leukemia after Transplantation

SIGNIFICANCE

We discuss the mechanisms of AML immune evasion including loss or downregulation of MHC class I and II, reduced TRAIL receptor expression, inhibitory metabolite production, inhibitory ligand expression, impaired proinflammatory cytokine production, and AML niche alterations.

Proposed Refinement of 2022 European LeukemiaNet Adverse-Risk Group of AML Patients Using a Real-World Cohort

Background/Objectives: The 2022 European LeukemiaNet (ELN 2022) is a widely used genotypic risk classification tool for the treatment and prognostication of acute myeloid leukemia (AML) patients. Our study evaluates its effectiveness in categorizing adverse-risk AML patients on standard therapy based on their overall survival (OS). Methods: We conducted a retrospective study involving 256 AML patients. Results: Those in the ELN 2022 adverse-risk group had the shortest OS (p < 0.0001) and were predominantly characterized by myelodysplasia-related (MR) mutations, complex karyotype (CK), monosomal karyotype (MK), and TP53 mutation (TP53 Mut). Subclassification and analysis of this adverse-risk group based on the TP53 Mut status revealed a significantly shorter OS compared to the adverse TP53 wild-type (TP53 WT) counterparts (p = 0.0036). We propose refining the ELN 2022 adverse-risk group into two categories, adverse TP53 Mut and adverse TP53 WT groups, to represent adverse- and ultra-adverse-risk groups, respectively. We used an external validation dataset to confirm our findings. Conclusions: This refinement allows for a more accurate classification of these adverse-risk patients based on their clinical outcomes.

Patterns and variations of copy number alterations in acute myeloid leukemia: insights from the LeukAtlas database

Recent pan-cancer analysis revealed the global pattern and potential aetiologies of copy number variation signatures in human cancers, particularly those derived from non-hematopoietic tissues. In sharp contrast, the generally low CNV burden in leukemia leaves the CNV landscape and variations largely unexplored, impeding understanding of CNV in leukemia development. Through a comprehensive compilation of public datasets, we constructed LeukAtlas ( https://ngdc.cncb.ac.cn/leukemia ), a user-friendly database encompassing 12,597 CNVs from 1446 AML samples across diverse subtypes and age groups, providing tools for multidimensional CNV analysis. Our analyses suggested the CNV levels significantly varied among AML patients. We discovered two previously unknown CNV patterns in adult AML patients, dominated by segmental LOH and/or minor gain, which have been shown to be associated with chromosomal instability in solid tumors. Additionally, we defined two potential new AML subgroups based on CNVs status, providing new stratification markers within the existing karyotype framework. Representing the most extensive CNV collection in AML, LeukAtlas is a valuable resource for exploring the role of CNVs in the pathogenesis and prognosis stratification of leukemia. Interrogation of this database uncovers novel subclasses with unique CNV profiles and reveals heterogeneous CNV patterns in AML, demonstrating the potential role of chromosomal instability in AML progression.

Allo-HCT refined ELN 2022 risk classification: validation of the Adverse-Plus risk group in AML patients undergoing allogeneic hematopoietic cell transplantation within the Spanish Group for Hematopoietic Cell Transplantation (GETH-TC)

This multicenter retrospective study by GETH-TC validates the prognostic value of the Allo-HCT Refined ELN 2022 risk classification in allografted AML patients. The new classification refines the ELN 2022 risk classification, dividing adverse-risk patients into two subgroups: Adv-Plus (AdvP), including those with complex karyotype, MECOM (EVI1) rearrangement, or TP53 mutations/del(17p), and an additional adverse group (Adv*). The study included 651 AML patients treated with at least one line of anthracycline-based induction therapy and in complete remission. According to the Allo-HCT Refined ELN 2022 risk classification, 19.4% (n = 126) patients were classified into the Favorable (Fav) risk, 38.1% (n = 248) into the Intermediate (Int) risk, 27.2% (n = 177) in the Adv* and 15.4% (n = 100) in the AdvP. Outcomes were significantly poorer for patients allocated in the AdvP risk group (5-year OS rate: 32.3%, 5-year LFS rate: 24.3%, both p < 0.001 with the rest of subgroups) and a higher CIR (5-year CIR: 64.3%, p < 0.001). Patients in the Adv* risk group had similar outcomes than patients in the Int risk group (5-year OS rate: 70.2% vs. 66.7%, p = 0.69, 5-year LFS rate: 63.8% vs. 55.9%, p = 0.33). Multivariate analysis confirmed the dismal outcomes for AdvP patients for OS: Hazard Ratio (HR) = 3.05, and LFS: HR = 2.66, both p < 0.001. Our findings validate the Allo-HCT Refined ELN 2022 classification as a robust prognostic tool, particularly highlighting the poor outcomes for the AdvP subgroup.

RNA splicing as a therapeutic target in myelodysplastic syndromes

Myelodysplastic syndromes (MDS) represent a heterogeneous group of hematological disorders and are more commonly found in people over the age of 60. MDS patients exhibit peripheral blood cytopenias and carry an increased risk of disease progression to acute myeloid leukemia (AML). Splicing factor mutations (including genes SF3B1, SRSF2, U2AF1, and ZRSR2) are early events identified in more than 50% of MDS cases. These mutations cause aberrant pre-mRNA splicing and impact MDS pathophysiology. Emerging evidence shows that splicing factor-mutant cells are more sensitive to perturbations targeting the spliceosome, aberrantly spliced genes and/or their regulated molecular pathways. This review summarizes current therapeutic strategies and ongoing efforts targeting splicing factor mutations for the treatment of MDS.

Single-cell multiomics analysis reveals dynamic clonal evolution and targetable phenotypes in acute myeloid leukemia with complex karyotype

Chromosomal instability is a major driver of intratumoral heterogeneity (ITH), promoting tumor progression. In the present study, we combined structural variant discovery and nucleosome occupancy profiling with transcriptomic and immunophenotypic changes in single cells to study ITH in complex karyotype acute myeloid leukemia (CK-AML). We observed complex structural variant landscapes within individual cells of patients with CK-AML characterized by linear and circular breakage-fusion-bridge cycles and chromothripsis. We identified three clonal evolution patterns in diagnosis or salvage CK-AML (monoclonal, linear and branched polyclonal), with 75% harboring multiple subclones that frequently displayed ongoing karyotype remodeling. Using patient-derived xenografts, we demonstrated varied clonal evolution of leukemic stem cells (LSCs) and further dissected subclone-specific drug-response profiles to identify LSC-targeting therapies, including BCL-xL inhibition. In paired longitudinal patient samples, we further revealed genetic evolution and cell-type plasticity as mechanisms of disease progression. By dissecting dynamic genomic, phenotypic and functional complexity of CK-AML, our findings offer clinically relevant avenues for characterizing and targeting disease-driving LSCs.

Complex karyotypes in hematologic disorders: a 12-year single-center study from Lebanon

Conventional cytogenetic analysis is an important tool for the diagnosis of many hematologic disorders (HD). A karyotype is designed as « complex » when several alterations are detected. However, there is no clear consensus on the exact definition of a complex karyotype (CK), and there is a lack of studies that exclusively analyze CK in the literature. Complex karyotypes were analyzed over a period of 12 years at the Jacques Loiselet Center for Medical Genetics and Genomics (CGGM) at Saint Joseph University in Beirut (USJ) in Lebanon. 255 CK were analyzed with their associated chromosomal abnormalities (CA) detected. Out of 255 patients, 59.22% were males with a mean age of 59 years. The most common anomaly associated with CK was hyperdiploidy with a prevalence of 22.41%, which is different from a previously published study. To our knowledge, this represents the largest series of CK, particularly within the Middle East region. This study underscores the critical role of conventional cytogenetics in detecting CK, ultimately contributing to improved management of HD. Further investigations focusing on CK are needed.

Comparative Analysis of AML Classification Systems: Evaluating the WHO, ICC, and ELN Frameworks and Their Distinctions

Comprehensive analyses of the molecular heterogeneity of acute myelogenous leukemia, AML, particularly when malignant cells retain normal karyotype, has significantly evolved. In 2022, significant revisions were introduced in the World Health Organization (WHO) classification and the European LeukemiaNet (ELN) 2022 guidelines of acute myeloid leukemia (AML). These revisions coincided with the inception of the first version of the International Consensus Classification (ICC) for AML. These modifications aim to improve diagnosis and treatment outcomes via a comprehensive incorporation of sophisticated genetic and clinical parameters as well as facilitate accruals to innovative clinical trials. Key updates include modifications to the blast count criteria for AML diagnosis, with WHO 2022 eliminating the ≥20% blast requirement in the presence of AML-defining abnormalities and ICC 2022 setting a 10% cutoff for recurrent genetic abnormalities. Additionally, new categories, such as AML with mutated TP53 and MDS/AML, were introduced. ELN 2022 guidelines retained risk stratification approach and emphasized the critical role of measurable residual disease (MRD) that increased the use of next-generation sequencing (NGS) and flow cytometry testing. These revisions underscore the importance of precise classification for targeted treatment strategies and improved patient outcomes. How much difference versus concordance these classifications present and the impact of those on clinical practice is a continuing discussion.

Cancer cytogenetics in a genomics world: Wedding the old with the new

Since the discovery of the Philadelphia chromosome in 1960, cytogenetic studies have been instrumental in detecting chromosomal abnormalities that can inform cancer diagnosis, treatment, and risk assessment efforts. The initial expansion of cancer cytogenetics was with fluorescence in situ hybridization (FISH) to assess submicroscopic alterations in dividing or non-dividing cells and has grown into the incorporation of chromosomal microarrays (CMA), and next generation sequencing (NGS). These molecular technologies add additional dimensions to the genomic assessment of cancers by uncovering cytogenetically invisible molecular markers. Rapid technological and bioinformatic advances in NGS are so promising that the idea of performing whole genome sequencing as part of routine patient care may soon become economically and logistically feasible. However, for now cytogenetic studies continue to play a major role in the diagnostic testing and subsequent assessments in leukemia with other genomic studies serving as complementary testing options for detection of actionable genomic abnormalities. In this review, we discuss the role of conventional cytogenetics (karyotyping, chromosome analysis) and FISH studies in hematological malignancies, highlighting the continued clinical utility of these techniques, the subtleties and complexities that are relevant to treating physicians and the unique strengths of cytogenetics that cannot yet be paralleled by the current high-throughput molecular technologies. Additionally, we describe how CMA, optical genome mapping (OGM), and NGS detect abnormalities that were beyond the capacity of cytogenetic studies and how an integrated approach (broad molecular testing) can contribute to the detection of actionable targets and variants in malignancies. Finally, we discuss advances in the field of genomic testing that are bridging the advantages of individual (single) cell based cytogenetic testing and broad genomic testing.

Evaluation of European LeukemiaNet 2022 risk classification in patients undergoing allogeneic haematopoietic stem cell transplantation for acute myeloid leukaemia: Identification of a very poor prognosis genetic group

European LeukemiaNet refined their risk classification of acute myeloid leukaemia (AML) in 2022 (ELN 2022) according to the two new myeloid classifications published the same year. We have retrospectively assessed the prognostic value of the ELN 2022 in 120 AML patients undergoing allogeneic haematopoietic cell transplantation (allo-HCT), including 99 in first complete response (CR1) from 2011 to 2021 in our centre. Adverse risk patients (Adv) presented inferior outcome in terms of overall survival (OS) and leukaemia-free survival (LFS) (OS [p = 0.003], LFS [p = 0.02]), confirmed in multivariate analysis (hazard ratio [HR] for OS = 2.00, p = 0.037). These results were also seen in patients allografted in CR1. Further analysis identified a subgroup named adverse-plus (AdvP), including complex karyotype, MECOM(EVI1) rearrangements and TP53 mutations, with worse outcomes than the rest of groups of patients, including the Adv (HR for OS: 3.14, p < 0.001, HR for LFS: 3.36, p < 0.001), with higher 2-year cumulative incidence of relapse (p < 0.001). Notably, within this analysis, the outcome of Adv and intermediate patients were similar. These findings highlight the prognostic value of ELN 2022 in patients undergoing allo-HCT, which can be improved by the recognition of a poor genetic subset (AdvP) within the Adv risk group.

A practical algorithm for acute myeloid leukaemia diagnosis following the updated 2022 classifications

Disease classification of complex and heterogenous diseases, such as acute myeloid leukaemia (AML), is continuously updated to define diagnoses, appropriate treatments, and assist research and education. Recent availability of molecular profiling techniques further benefits the classification of AML. The World Health Organization (WHO) classification of haematolymphoid tumours and the International Consensus Classification of myeloid neoplasms and acute leukaemia from 2022 are two updated versions of the WHO 2016 classification. As a consequence, the European LeukemiaNet 2022 recommendations on the diagnosis and management of AML in adults have been also updated. The current review provides a practical interpretation of these guidelines to facilitate the diagnosis of AML and discusses genetic testing, disease genetic heterogeneity, and FLT3 mutations. We propose a practical algorithm for the speedy diagnosis of AML. Future classifications may need to incorporate gene mutation combinations to enable personalised treatment regimens in the management of patients with AML.

Precision Medicine Approaches in Acute Myeloid Leukemia with Adverse Genetics

The treatment of acute myeloid leukemia (AML) with adverse genetics remains unsatisfactory, with very low response rates to standard chemotherapy and shorter durations of remission commonly observed in these patients. The complex biology of AML with adverse genetics is continuously evolving. Herein, we discuss recent advances in the field focusing on the contribution of molecular drivers of leukemia biogenesis and evolution and on the alterations of the immune system that can be exploited with immune-based therapeutic strategies. We focus on the biological rationales for combining targeted therapy and immunotherapy, which are currently being investigated in ongoing trials, and could hopefully ameliorate the poor outcomes of patients affected by AML with adverse genetics.

Case report: One case of acute myeloid leukemia M3 with atypical morphology

Acute promyelocytic leukemia (APL) is a type of acute myeloid leukemia. About 2% of APL is characterized by atypical rearrangements. Here we reported one APL case with atypical manifestations and morphology. A 35-year-old woman patient, mainly due to fatigue, poor appetite for over 10 days and intermittent fever for 3 days. combined with the results of flow cytometry, fusion gene and chromosome, the patient was diagnosed as AML-M3 with atypical morphology. Double induction therapy with retinoic acid and arsenous acid was immediately administrated. Idarubicin was administrated on the 18th day. A re-examination was performed in the 5th week, both the blood routine test and myelogram showed normal results, and the fusion gene turned negative, indicating complete remission. When atypical morphology occurs, peripheral blood POX staining may be performed to check the abnormal cells. Flow cytometry, chromosome analysis, and fusion gene analysis are also required for further diagnosis.

Cytogenetics and genomics of acute myeloid leukemia

The diversity of genetic and genomic abnormalities observed in acute myeloid leukemia (AML) reflects the complexity of these hematologic neoplasms. The detection of cytogenetic and molecular alterations is fundamental to diagnosis, risk stratification and treatment of AML. Chromosome rearrangements are well established in the diagnostic classification of AML, as are some gene mutations, in several international classification systems. Additionally, the detection of new mutational profiles at relapse and identification of mutations in the pre- and post-transplant settings are illuminating in understanding disease evolution and are relevant to the risk assessment of AML patients. In this review, we discuss recurrent cytogenetic abnormalities, as well as the detection of recurrent mutations, within the context of a normal karyotype, and in the setting of chromosome abnormalities. Two new classification schemes from the WHO and ICC are described, comparing these classifications in terms of diagnostic criteria and entity definition in AML. Finally, we discuss ways in which genomic sequencing can condense the detection of gene mutations and chromosome abnormalities into a single assay.

Identification of a Complex Karyotype Signature with Clinical Implications in AML and MDS-EB Using Gene Expression Profiling

Complex karyotype (CK) is associated with a poor prognosis in both acute myeloid leukemia (AML) and myelodysplastic syndrome with excess blasts (MDS-EB). Transcriptomic analyses have improved our understanding of the disease and risk stratification of myeloid neoplasms; however, CK-specific gene expression signatures have been rarely investigated. In this study, we developed and validated a CK-specific gene expression signature. Differential gene expression analysis between the CK and non-CK groups using data from 348 patients with AML and MDS-EB from four cohorts revealed enrichment of the downregulated genes localized on chromosome 5q or 7q, suggesting that haploinsufficiency due to the deletion of these chromosomes possibly underlies CK pathogenesis. We built a robust transcriptional model for CK prediction using LASSO regression for gene subset selection and validated it using the leave-one-out cross-validation method for fitting the logistic regression model. We established a 10-gene CK signature (CKS) predictive of CK with high predictive accuracy (accuracy 94.22%; AUC 0.977). CKS was significantly associated with shorter overall survival in three independent cohorts, and was comparable to that of previously established risk stratification models for AML. Furthermore, we explored of therapeutic targets among the genes comprising CKS and identified the dysregulated expression of superoxide dismutase 1 (SOD1) gene, which is potentially amenable to SOD1 inhibitors.

Entospletinib with decitabine in acute myeloid leukemia with mutant TP53 or complex karyotype: A phase 2 substudy of the Beat AML Master Trial

BACKGROUND

Patients with acute myeloid leukemia (AML) who have tumor protein p53 (TP53) mutations or a complex karyotype have a poor prognosis, and hypomethylating agents are often used. The authors evaluated the efficacy of entospletinib, an oral inhibitor of spleen tyrosine kinase, combined with decitabine in this patient population.

METHODS

This was a multicenter, open-label, phase 2 substudy of the Beat AML Master Trial (ClinicalTrials.gov identifier NCT03013998) using a Simon two-stage design. Eligible patients aged 60 years or older who had newly diagnosed AML with mutations in TP53 with or without a complex karyotype (cohort A; n = 45) or had a complex karyotype without TP53 mutation (cohort B; n = 13) received entospletinib 400 mg twice daily with decitabine 20 mg/m2 on days 1-10 every 28 days for up to three induction cycles, followed by up to 11 consolidation cycles, in which decitabine was reduced to days 1-5. Entospletinib maintenance was given for up to 2 years. The primary end point was complete remission (CR) and CR with hematologic improvement by up to six cycles of therapy.

RESULTS

The composite CR rates for cohorts A and B were 13.3% (95% confidence interval, 5.1%-26.8%) and 30.8% (95% confidence interval, 9.1%-61.4%), respectively. The median duration of response was 7.6 and 8.2 months, respectively, and the median overall survival was 6.5 and 11.5 months, respectively. The study was stopped because the futility boundary was crossed in both cohorts.

CONCLUSIONS

The combination of entospletinib and decitabine demonstrated activity and was acceptably tolerated in this patient population; however, the CR rates were low, and overall survival was short. Novel treatment strategies for older patients with TP53 mutations and complex karyotype remain an urgent need.

Modern Risk Stratification of Acute Myeloid Leukemia in 2023: Integrating Established and Emerging Prognostic Factors

An accurate estimation of AML prognosis is complex since it depends on patient-related factors, AML manifestations at diagnosis, and disease genetics. Furthermore, the depth of response, evaluated using the level of MRD, has been established as a strong prognostic factor in several AML subgroups. In recent years, this rapidly evolving field has made the prognostic evaluation of AML more challenging. Traditional prognostic factors, established in cohorts of patients treated with standard intensive chemotherapy, are becoming less accurate as new effective therapies are emerging. The widespread availability of next-generation sequencing platforms has improved our knowledge of AML biology and, consequently, the recent ELN 2022 recommendations significantly expanded the role of new gene mutations. However, the impact of rare co-mutational patterns remains to be fully disclosed, and large international consortia such as the HARMONY project will hopefully be instrumental to this aim. Moreover, accumulating evidence suggests that clonal architecture plays a significant prognostic role. The integration of clinical, cytogenetic, and molecular factors is essential, but hierarchical methods are reaching their limit. Thus, innovative approaches are being extensively explored, including those based on "knowledge banks". Indeed, more robust prognostic estimations can be obtained by matching each patient's genomic and clinical data with the ones derived from very large cohorts, but further improvements are needed.

The Prognostic Value of TP53 Mutations in Adult Acute Myeloid Leukemia: A Meta-Analysis

OBJECTIVE

Mutations of the tumor protein p53 (TP53) gene were considered to be associated with an unfavorable prognosis in acute myeloid leukemia (AML). This meta-analysis aimed to systematically elucidate the prognostic value of TP53 mutation in adult patients with AML.

METHOD

A comprehensive literature search was conducted for eligible studies published before August 2021. The primary endpoint was overall survival (OS). Pooled hazard ratios (HRs) and their 95% confidence intervals (CIs) were calculated for prognostic parameters. Subgroup analyses based on intensive treatment were performed.

RESULTS

Thirty-two studies with 7,062 patients were included. As compared to wild-type carriers, AML patients with TP53 mutations had significantly shorter OS (HR: 2.40, 95% CI: 2.16-2.67, I2: 46.6%). Similar results were found in DFS (HR: 2.87, 95% CI: 1.88-4.38), EFS (HR: 2.56, 95% CI: 1.97-3.31), and RFS (HR: 2.40, 95% CI: 1.79-3.22). Mutant TP53 predicted inferior OS (HR: 2.77, 95% CI: 2.41-3.18) in the intensively treated AML subgroup, compared with the non-intensively treated group (HR: 1.89, 95% CI: 1.58-2.26). Among intensively-treated AML patients, the age of 65 did not affect the prognostic value of TP53 mutations. Besides, TP53 mutation was also strongly associated with an elevated risk of adverse cytogenetics, which conferred a dismal OS in AML patients (HR: 2.03, 95% CI: 1.74-2.37).

CONCLUSION

TP53 mutation exhibits a promising potential for discriminating AML patients with a worse prognosis, thus being capable of serving as a novel tool for prognostication and therapeutic decision-making in the management of AML.

Single-Cell Next-Generation Sequencing to Monitor Hematopoietic Stem-Cell Transplantation: Current Applications and Future Perspectives

Acute myeloid leukemia (AML) and myelodysplastic syndrome (MDS) are genetically complex and diverse diseases. Such complexity makes challenging the monitoring of response to treatment. Measurable residual disease (MRD) assessment is a powerful tool for monitoring response and guiding therapeutic interventions. This is accomplished through targeted next-generation sequencing (NGS), as well as polymerase chain reaction and multiparameter flow cytometry, to detect genomic aberrations at a previously challenging leukemic cell concentration. A major shortcoming of NGS techniques is the inability to discriminate nonleukemic clonal hematopoiesis. In addition, risk assessment and prognostication become more complicated after hematopoietic stem-cell transplantation (HSCT) due to genotypic drift. To address this, newer sequencing techniques have been developed, leading to more prospective and randomized clinical trials aiming to demonstrate the prognostic utility of single-cell next-generation sequencing in predicting patient outcomes following HSCT. This review discusses the use of single-cell DNA genomics in MRD assessment for AML/MDS, with an emphasis on the HSCT time period, including the challenges with current technologies. We also touch on the potential benefits of single-cell RNA sequencing and analysis of accessible chromatin, which generate high-dimensional data at the cellular resolution for investigational purposes, but not currently used in the clinical setting.

Whole transcriptome sequencing reveals HOXD11-AGAP3, a novel fusion transcript in the Indian acute leukemia cohort

Introduction: Acute leukemia is a heterogeneous disease with distinct genotypes and complex karyotypes leading to abnormal proliferation of hematopoietic cells. According to GLOBOCAN reports, Asia accounts for 48.6% of leukemia cases, and India reports ~10.2% of all leukemia cases worldwide. Previous studies have shown that the genetic landscape of AML in India is significantly different from that in the western population by WES. Methods: We have sequenced and analyzed 9 acute myeloid leukemia (AML) transcriptome samples in the present study. We performed fusion detection in all the samples and categorized the patients based on cytogenetic abnormalities, followed by a differential expression analysis and WGCNA analysis. Finally, Immune profiles were obtained using CIBERSORTx. Results: We found a novel fusion HOXD11-AGAP3 in 3 patients, BCR-ABL1 in 4, and KMT2A-MLLT3 in one patient. Categorizing the patients based on their cytogenetic abnormalities and performing a differential expression analysis, followed by WGCNA analysis, we observed that in the HOXD11-AGAP3 group, correlated co-expression modules were enriched with genes from pathways like Neutrophil degranulation, Innate Immune system, ECM degradation, and GTP hydrolysis. Additionally, we obtained HOXD11-AGAP3-specific overexpression of chemokines CCL28 and DOCK2. Immune profiling using CIBRSORTx revealed differences in the immune profiles across all the samples. We also observed HOXD11-AGAP3-specific elevated expression of lincRNA HOTAIRM1 and its interacting partner HOXA2. Discussion: The findings highlight population-specific HOXD11-AGAP3, a novel cytogenetic abnormality in AML. The fusion led to alterations in immune system represented by CCL28 and DOCK2 over-expression. Interestingly, in AML, CCL28 is known prognostic marker. Additionally, non-coding signatures (HOTAIRM1) were observed specific to the HOXD11-AGAP3 fusion transcript which are known to be implicated in AML.

Validation and refinement of the 2022 European LeukemiaNet genetic risk stratification of acute myeloid leukemia

The revised 2022 European LeukemiaNet (ELN) AML risk stratification system requires validation in large, homogeneously treated cohorts. We studied 1118 newly diagnosed AML patients (median age, 58 years; range, 18-86 years) who received cytarabine-based induction chemotherapy between 1999 and 2012 and compared ELN-2022 to the previous ELN-2017 risk classification. Key findings were validated in a cohort of 1160 mostly younger patients. ELN-2022 reclassified 15% of patients, 3% into more favorable, and 12% into more adverse risk groups. This was mainly driven by patients reclassified from intermediate- to adverse-risk based on additional myelodysplasia-related mutations being included as adverse-risk markers. These patients (n = 79) had significantly better outcomes than patients with other adverse-risk genotypes (5-year OS, 26% vs. 12%) and resembled the remaining intermediate-risk group. Overall, time-dependent ROC curves and Harrel's C-index controlling for age, sex, and AML type (de novo vs. sAML/tAML) show slightly worse prognostic discrimination of ELN-2022 compared to ELN-2017 for OS. Further refinement of ELN-2022 without including additional genetic markers is possible, in particular by recognizing TP53-mutated patients with complex karyotypes as "very adverse". In summary, the ELN-2022 risk classification identifies a larger group of adverse-risk patients at the cost of slightly reduced prognostic accuracy compared to ELN-2017.

TP53 mutation variant allele frequency of ≥10% is associated with poor prognosis in therapy-related myeloid neoplasms

Revised diagnostic criteria for myeloid neoplasms (MN) issued by the International Consensus Classification (ICC) and the World Health Organization (WHO) recommended major change pertaining to TP53-mutated (TP53mut) MN. However, these assertions have not been specifically examined in therapy-related myeloid neoplasm (t-MN), a subset enriched with TP53mut. We analyzed 488 t-MN patients for TP53mut. At least one TP53mut with variant allele frequency (VAF) ≥ 2% with or without loss of TP53 locus was noted in 182 (37.3%) patients and 88.2% of TP53mut t-MN had a VAF ≥10%. TP53mut t-MN with VAF ≥ 10% had a distinct clinical and biological profile compared to both TP53mut VAF < 10% and wild-type TP53 (TP53wt) cases. Notably, TP53mut VAF ≥ 10% had a significantly shorter survival compared to TP53wt (8.3 vs. 21.6 months; P < 0.001), while the survival of TP53mut VAF < 10% was comparable to TP53wt. Within TP53mut VAF ≥ 10% cohort, the inferior outcomes persisted irrespective of the single- or multi-hit status, co-mutation pattern, or treatments received. Finally, survival of TP53mut patients was poor across all the blast categories and MDS patients with >10% blasts had inferior survival compared to <5%. In summary, TP53mut VAF ≥10% signified a clinically and molecularly homogenous cohort regardless of the allelic status.

The increasingly blurred line between induction, consolidation and maintenance in acute myeloid leukaemia

Since the early 1970s, the treatment of acute myeloid leukaemia (AML) has undergone a major transformation. Initially based on only two drugs, an anthracycline and cytosine arabinoside, the aim of therapy was to achieve a haematological response allowing patients to recover and go home. Back in those early days, cure was not a realistic expectation. Treatment was analogous to a heart attack; upon recovery and a short respite, recurrence and death inevitably followed. Over the subsequent decades, slow but remarkable progress was made such that a subgroup of young adults could become long-term survivors. This astonishing feat was achieved initially without the use of new drugs. Supportive care played a major role with the widespread availability of platelet transfusions and improved antimicrobial therapy, particularly antifungal. No less important was the better use of existing drugs and the development of allogeneic haematopoietic cell transplantation. While initially the focus was on maximal tolerated therapy, an understanding of the immunologic role of allogeneic transplantation, better genetic characterization of the biology of the disease, advanced tools for detection of minimal disease as well as the recent development of new drugs changed the focus to a more refined approach targeting patients who are more likely to respond. Clearly, the historical paradigm where the term AML was generic and applicable to all patients requires a rethinking from the traditional therapeutic demarcations of therapy into phases of induction, consolidation and maintenance. These evolving new concepts and paradigm will be herein considered.

Clinical features of complex karyotype in newly diagnosed acute myeloid leukemia

Complex karyotype acute myeloid leukemia (CK-AML) has been classified as an adverse-risk subtype. Although a few reports have further classified CK-AML as typical (including monosomy of chromosomes 5, 7 and 17 or deletion of 5q, 7q and/or 17p) or atypical, the clinical features of these subtypes in Japanese patients remain unclear. We retrospectively analyzed a total of 115 patients with CK-AML, including 77 with typical CK-AML and 38 with atypical CK-AML. Median overall survival (OS) was significantly shorter in patients with typical CK-AML than atypical CK-AML (143 days vs. 369 days, P = 0.009). Among patients with typical CK-AML, those with monosomy 17 or deletion of 17p had significantly shorter OS than patients without such abnormalities (105 days vs. 165 days, P = 0.033). TP53 mutations were more predominant in patients with typical CK-AML than in patients with atypical CK-AML (69.7% vs. 32.4%, P < 0.001). Patients with typical CK-AML had a poor prognosis regardless of TP53 mutation status. Among patients with atypical CK-AML, however, prognosis was worse for those with the TP53 mutation than those without the mutation. In conclusion, prognosis is extremely poor for both typical CK-AML and atypical CK-AML with TP53 mutation.

The transcriptomic landscape of elderly acute myeloid leukemia identifies B7H3 and BANP as a favorable signature in high-risk patients

Acute myeloid leukemia (AML) in the elderly remains a clinical challenge, with a five-year overall survival rate below 10%. The current ELN 2017 genetic risk classification considers cytogenetic and mutational characteristics to stratify fit AML patients into different prognostic groups. However, this classification is not validated for elderly patients treated with a non-intensive approach, and its performance may be suboptimal in this context. Indeed, the transcriptomic landscape of AML in the elderly has been less explored and it might help stratify this group of patients. In the current study, we analyzed the transcriptome of 224 AML patients > 65 years-old at diagnosis treated in the Spanish PETHEMA-FLUGAZA clinical trial in order to identify new prognostic biomarkers in this population. We identified a specific transcriptomic signature for high-risk patients with mutated TP53 or complex karyotype, revealing that low expression of B7H3 gene with high expression of BANP gene identifies a subset of high-risk AML patients surviving more than 12 months. This result was further validated in the BEAT AML cohort. This unique signature highlights the potential of transcriptomics to identify prognostic biomarkers in in elderly AML.

Molecular characterization of AML‐MRC reveals TP53 mutation as an adverse prognostic factor irrespective of MRC ‐defining criteria, TP53 allelic state, or TP53 variant allele frequency

BACKGROUND

Acute myeloid leukemia with myelodysplasia-related changes (AML-MRC) generally confers poor prognosis, however, patient outcomes are heterogeneous. The impact of TP53 allelic state and variant allele frequency (VAF) in AML-MRC remains poorly defined.

METHODS

We retrospectively evaluated 266 AML-MRC patients who had NGS testing at our institution from 2014 to 2020 and analyzed their clinical outcomes based on clinicopathological features.

RESULTS

TP53 mutations were associated with cytogenetic abnormalities in 5q, 7q, 17p, and complex karyotype. Prognostic evaluation of TP53^MUT AML-MRC revealed no difference in outcome between TP53 double/multi-hit state and single-hit state. Patients with high TP53^MUT variant allele frequency (VAF) had inferior outcomes compared to patients with low TP53^MUT VAF. When compared to TP53^WT patients, TP53^MUT patients had inferior outcomes regardless of MRC-defining criteria, TP53 allelic state, or VAF. TP53 mutations and elevated serum LDH were independent predictors for inferior OS and EFS, while PHF6 mutations and transplantation were independent predictors for favorable OS and EFS. NRAS mutation was an independent predictor for favorable EFS.

CONCLUSIONS

Our study suggests that TP53^MUT AML-MRC defines a very-high-risk subentity of AML in which novel therapies should be explored.

Real-World Experience of Measurable Residual Disease Response and Prognosis in Acute Myeloid Leukemia Treated with Venetoclax and Azacitidine

The prognostic value of measurable residual disease (MRD) by flow cytometry in acute myeloid leukemia (AML) patients treated with non-intensive therapy is relatively unexplored. The clinical value of MRD threshold below 0.1% is also unknown after non-intensive therapy. In this study, MRD to a sensitivity of 0.01% was analyzed in sixty-three patients in remission after azacitidine/venetoclax treatment. Multivariable cox regression analysis identified prognostic factors associated with cumulative incidence of relapse (CIR), progression-free survival (PFS) and overall survival (OS). Patients who achieved MRD < 0.1% had a lower relapse rate than those who were MRD ≥ 0.1% at 18 months (13% versus 57%, p = 0.006). Patients who achieved an MRD-negative CR had longer median PFS and OS (not reached and 26.5 months) than those who were MRD-positive (12.6 and 10.3 months, respectively). MRD < 0.1% was an independent predictor for CIR, PFS, and OS, after adjusting for European Leukemia Net (ELN) risk, complex karyotype, and transplant (HR 5.92, 95% CI 1.34−26.09, p = 0.019 for PFS; HR 2.60, 95% CI 1.02−6.63, p = 0.046 for OS). Only an MRD threshold of 0.1%, and not 0.01%, was predictive for OS. Our results validate the recommended ELN MRD cut-off of 0.1% to discriminate between patients with improved CIR, PFS, and OS after azacitidine/venetoclax therapy.

Honokiol Induces Ferroptosis by Upregulating HMOX1 in Acute Myeloid Leukemia Cells

Acute myeloid leukemia (AML) is one of the malignant hematological cancers with high mortality. Finding a more effective and readily available treatment is of the utmost importance. Here, we aimed to identify the anti-leukemia effect of a natural small molecule compound honokiol on a panel of AML cell lines, including THP-1, U-937, and SKM-1, and explored honokiol’s potential biological pathways and mechanisms. The results showed that honokiol decreased the viability of the targeted AML cells, induced their cell cycle arrest at G0/G1 phase, and inhibited their colony-formation capacity. Honokiol also triggers a noncanonical ferroptosis pathway in THP-1 and U-937 cells by upregulating the level of intracellular lipid peroxide and HMOX1 significantly. Subsequent studies verified that HMOX1 was a critical target in honokiol-induced ferroptosis. These results reveal that honokiol is an effective anti-leukemia agent in AML cell lines and may be a potential ferroptosis activator in AML.

Mapping incidence and mortality of leukemia and its subtypes in 21 world regions in last three decades and projections to 2030

This study examines the burden of leukemia and its subtypes at the global, regional, and national levels in 21 world regions and 204 countries in the last three decades. The estimates of incidence, deaths, and age-standardized rates of leukemia for 21 regions and 204 countries for 1990-2019 were extracted from the Global Burden of Disease 2019 study. Average annual percentage change in 1990-2019 for 21 regions was utilized for projecting leukemia burden in 2030. Globally, there were 643,579 [586,980-699,729] incident cases and 334,592 [306,818-360,214] deaths in 2019 due to leukemia, up from 474,924 [388,559-560,550] cases and 263,263 [233,664-298,696] deaths in 1990. Between 1990 and 2019, the age-standardized incidence rate (ASIR) decreased from 9.6 [8.1-11.0] in 1990 to 8.2 [7.5-8.9] per 100,000 person-years in 2019, and the age-standardized mortality rate (ASMR) decreased from 5.8/100,000 [5.2-6.4] in 1990 to 4.3/100,000 [3.9-4.6] in 2019. Between 1990 and 2019, the ASIR decreased in majority of regions except Western Europe and high-income Asia Pacific, whereas the ASMR decreased in all 21 regions. In 2019, country-wise, the ASIR varied from 3.0/100,000 [2.3-3.7] in Palau to 35.1/100,000 [26.4-47.2] in San Marino and the ASMR spanned from 2.3/100,000 [1.7-2.8] in San Marino to 15.8/100,000 [12.0-20.4] in Syria. As per our projections, globally, there will be 720,168 incident cases and 367,804 deaths due to leukemia in 2030. Substantial improvements have been witnessed in leukemia mortality rates in all regions, especially high-income regions and countries. Health care policies focusing on diagnostic improvements, cancer registration, and newer therapeutics at reduced cost or with insurance coverage are needed in low and middle-income countries.

MicroRNA-139, an Emerging Gate-Keeper in Various Types of Cancer

Mounting data show that MIR139 is commonly silenced in solid cancer and hematological malignancies. MIR139 acts as a critical tumor suppressor by tuning the cellular response to different types of stress, including DNA damage, and by repressing oncogenic signaling pathways. Recently, novel insights into the mechanism of MIR139 silencing in tumor cells have been described. These include epigenetic silencing, inhibition of POL-II transcriptional activity on gene regulatory elements, enhanced expression of competing RNAs and post-transcriptional regulation by the microprocessor complex. Some of these MIR139-silencing mechanisms have been demonstrated in different types of cancer, suggesting that these are more general oncogenic events. Reactivation of MIR139 expression in tumor cells causes inhibition of tumor cell expansion and induction of cell death by the repression of oncogenic mRNA targets. In this review, we discuss the different aspects of MIR139 as a tumor suppressor gene and give an overview on different transcriptional mechanisms regulating MIR139 in oncogenic stress and across different types of cancer. The novel insights into the expression regulation and the tumor-suppressing activities of MIR139 may pave the way to new treatment options for cancer.

ERG amplification is a secondary recurrent driver event in myeloid malignancy with complex karyotype and TP53 mutations

ERG is a transcription factor encoded on chromosome 21q22.2 with important roles in hematopoiesis and oncogenesis of prostate cancer. ERG amplification has been identified as one of the most common recurrent events in acute myeloid leukemia with complex karyotype (AML-CK). In this study, we uncover 3 different modes of ERG amplification in AML-CK. Importantly, we present evidence to show that ERG amplification is distinct from intrachromosomal amplification of chromosome 21 (iAMP21), a hallmark segmental amplification frequently encompassing RUNX1 and ERG in a subset of high-risk B-lymphoblastic leukemia. We also characterize the association with TP53 aberrations and other chromosomal aberrations, including chromothripsis. Lastly, we show that ERG amplification can initially emerge as subclonal events in low grade myeloid neoplasms. These findings demonstrate that ERG amplification is a recurrent secondary driver event in AML and raise the tantalizing possibility of ERG as a therapeutic target. This article is protected by copyright. All rights reserved.

TP53 mutation defines a unique subgroup within complex karyotype de novo and therapy-related MDS/AML

Among patients with MDS and AML, the presence of TP53 mutation in the context of CK identifies a homogeneously aggressive disease.

TP53 mutation (in particular multihit) identifies an aggressive disease, irrespective of the blast count or therapy-relatedness.

A subset of myelodysplastic syndromes (MDS) and acute myeloid leukemia (AML) show complex karyotype (CK), and these cases include a relatively high proportion of cases of therapy-related myeloid neoplasms and TP53 mutations. We aimed to evaluate the clinicopathologic features of outcome of 299 AML and MDS patients with CK collected from multiple academic institutions. Mutations were present in 287 patients (96%), and the most common mutation detected was in TP53 gene (247, 83%). A higher frequency of TP53 mutations was present in therapy-related cases (P = .008), with a trend for worse overall survival (OS) in therapy-related patients as compared with de novo disease (P = .08) and within the therapy-related group; the presence of TP53 mutation strongly predicted for worse outcome (P = .0017). However, there was no difference in survival between CK patients based on categorization of AML vs MDS (P = .96) or presence of absence of circulating blasts ≥1% (P = .52). TP53-mutated patients presented with older age (P = .06) and lower hemoglobin levels (P = .004) and marrow blast counts (P = .02) compared with those with CK lacking TP53 mutation. Multivariable analysis identified presence of multihit TP53 mutation as strongest predictor of worse outcome, whereas neither a diagnosis of AML vs MDS nor therapy-relatedness independently influenced OS. Our findings suggest that among patients with MDS and AML, the presence of TP53 mutation (in particular multihit TP53 mutation) in the context of CK identifies a homogeneously aggressive disease, irrespective of the blast count at presentation or therapy-relatedness. The current classification of these cases into different disease categories artificially separates a single biologic disease entity.

European LeukemiaNet 2017 risk stratification for acute myeloid leukemia: validation in a risk-adapted protocol

The ELN 2017 classification has been validated in a risk-adapted intensive protocol, supporting its utility to predict outcome.

Within the ELN 2017 adverse group, there is a subset of patients (inv(3) and TP53 abnormalities) with a particularly poor prognosis.

The 2017 European LeukemiaNet (ELN 2017) guidelines for the diagnosis and management of acute myeloid leukemia (AML) have become fundamental guidelines to assess the prognosis and postremission therapy of patients. However, they have been retrospectively validated in few studies with patients included in different treatment protocols. We analyzed 861 patients included in the Cooperativo Para el Estudio y Tratamiento de las Leucemias Agudas y Mielodisplasias-12 risk-adapted protocol, which indicates cytarabine-based consolidation for patients allocated to the ELN 2017 favorable-risk group, whereas it recommends allogeneic stem cell transplantation (alloSCT) as a postremission strategy for the ELN 2017 intermediate- and adverse-risk groups. We retrospectively classified patients according to the ELN 2017, with 327 (48%), 109 (16%), and 245 (36%) patients allocated to the favorable-, intermediate-, and adverse-risk group, respectively. The 2- and 5-year overall survival (OS) rates were 77% and 70% for favorable-risk patients, 52% and 46% for intermediate-risk patients, and 33% and 23% for adverse-risk patients, respectively. Furthermore, we identified a subgroup of patients within the adverse group (inv(3)/t(3;3), complex karyotype, and/or TP53 mutation/17p abnormality) with a particularly poor outcome, with a 2-year OS of 15%. Our study validates the ELN 2017 risk stratification in a large cohort of patients treated with an ELN-2017 risk-adapted protocol based on alloSCT after remission for nonfavorable ELN subgroups and identifies a genetic subset with a very poor outcome that warrants investigation of novel strategies.

Molecular associations, clinical, and prognostic implications of PTPN11 mutations in acute myeloid leukemia (Alliance)

Patients with N-terminal SH2 domain PTPN11 mutations had an early death (<30 days) more often than those with phosphatase domain mutations.

PTPN11 mutations are associated with inferior outcomes in AML patients with wild-type NPM1.

Prognostic factors associated with chemotherapy outcomes in patients with acute myeloid leukemia (AML) are extensively reported, and one gene whose mutation is recognized as conferring resistance to several newer targeted therapies is protein tyrosine phosphatase non-receptor type 11 (PTPN11). The broader clinical implications of PTPN11 mutations in AML are still not well understood. The objective of this study was to determine which cytogenetic abnormalities and gene mutations co-occur with PTPN11 mutations and how PTPN11 mutations affect outcomes of patients treated with intensive chemotherapy. We studied 1725 patients newly diagnosed with AML (excluding acute promyelocytic leukemia) enrolled onto the Cancer and Leukemia Group B/Alliance for Clinical Trials in Oncology trials. In 140 PTPN11-mutated patient samples, PTPN11 most commonly co-occurred with mutations in NPM1, DNMT3A, and TET2. PTPN11 mutations were relatively common in patients with an inv(3)(q21q26)/t(3;3)(q21;q26) and a normal karyotype but were very rare in patients with typical complex karyotype and core-binding factor AML. Mutations in the N-terminal SH2 domain of PTPN11 were associated with a higher early death rate than those in the phosphatase domain. PTPN11 mutations did not affect outcomes of NPM1-mutated patients, but these patients were less likely to have co-occurring kinase mutations (ie, FLT3-ITD), suggesting activation of overlapping signaling pathways. However, in AML patients with wild-type NPM1, PTPN11 mutations were associated with adverse patient outcomes, providing a rationale to study the biology and treatment approaches in this molecular group. This trial was registered at www.clinicaltrials.gov as #NCT00048958 (CALGB 8461), #NCT00899223 (CALGB 9665), and #NCT00900224 (CALGB 20202).

Association Analyses of TP53 Mutation With Prognosis, Tumor Mutational Burden, and Immunological Features in Acute Myeloid Leukemia

Acute myeloid leukemia (AML) is a heterogeneous disease related to a broad spectrum of molecular alterations. The successes of immunotherapies treating solid tumors and a deeper understanding of the immune systems of patients with hematologic malignancies have promoted the development of immunotherapies for the treatment of AML. And high tumor mutational burden (TMB) is an emerging predictive biomarker for response to immunotherapy. However, the association of gene mutation in AML with TMB and immunological features still has not been clearly elucidated. In our study, based on The Cancer Genome Atlas (TCGA) and BeatAML cohorts, 20 frequently mutated genes were found to be covered by both datasets in AML. And TP53 mutation was associated with a poor prognosis, and its mutation displayed exclusiveness with other common mutated genes in both datasets. Moreover, TP53 mutation correlated with TMB and the immune microenvironment. Gene Set Enrichment Analysis (GSEA) showed that TP53 mutation upregulated signaling pathways involved in the immune system. In summary, TP53 mutation is frequently mutated in AML, and its mutation is associated with dismal outcome, TMB, and immunological features, which may serve as a biomarker to predict immune response in AML.

Development of TP53 mutations over the course of therapy for acute myeloid leukemia

TP53 mutations in acute myeloid leukemia (AML) are associated with resistance to standard treatments and dismal outcomes. The incidence and prognostic impact of the emergence of newly detectable TP53 mutations over the course of AML therapy has not been well described. We retrospectively analyzed 200 patients with newly diagnosed TP53 wild type AML who relapsed after or were refractory to frontline therapy. Twenty-nine patients (15%) developed a newly detectable TP53 mutation in the context of relapsed/refractory disease. The median variant allelic frequency (VAF) was 15% (range, 1.1%-95.6%). TP53 mutations were more common after intensive therapy versus lower-intensity therapy (23% vs. 10%, respectively; p = 0.02) and in patients who had undergone hematopoietic stem cell transplant versus those who had not (36% vs. 12%, respectively; p = 0.005). Lower TP53 VAF was associated with an increased likelihood of complete remission (CR) or CR with incomplete hematologic recovery (CRi) compared to higher TP53 VAF (CR/CRi rate of 41% for VAF < 20% vs. 13% for VAF ≥ 20%, respectively). The median overall survival (OS) after acquisition of TP53 mutation was 4.6 months, with a 1-year OS rate of 19%. TP53 VAF at relapse was significantly associated with OS; the median OS of patients with TP53 VAF ≥ 20% was 3.5 months versus 6.1 months for those with TP53 VAF < 20% (p < 0.05). In summary, new TP53 mutations may be acquired throughout the course of AML therapy. Sequential monitoring for TP53 mutations is likely to be increasingly relevant in the era of emerging TP53-targeting therapies for AML.

Roles of Histone Deacetylases in Acute Myeloid Leukemia With Fusion Proteins

Accurate orchestration of gene expression is critical for the process of normal hematopoiesis, and dysregulation is closely associated with leukemogenesis. Epigenetic aberration is one of the major causes contributing to acute myeloid leukemia (AML), where chromosomal rearrangements are frequently found. Increasing evidences have shown the pivotal roles of histone deacetylases (HDACs) in chromatin remodeling, which are involved in stemness maintenance, cell fate determination, proliferation and differentiation, via mastering the transcriptional switch of key genes. In abnormal, these functions can be bloomed to elicit carcinogenesis. Presently, HDAC family members are appealing targets for drug exploration, many of which have been deployed to the AML treatment. As the majority of AML events are associated with chromosomal translocation resulting in oncogenic fusion proteins, it is valuable to comprehensively understand the mutual interactions between HDACs and oncogenic proteins. Therefore, we reviewed the process of leukemogenesis and roles of HDAC members acting in this progress, providing an insight for the target anchoring, investigation of hyperacetylated-agents, and how the current knowledge could be applied in AML treatment.

Novel Immune Cell-Based Therapies to Eradicate High-Risk Acute Myeloid Leukemia

Adverse genetic risk acute myeloid leukemia (AML) includes a wide range of clinical-pathological entities with extremely poor outcomes; thus, novel therapeutic approaches are needed. Promising results achieved by engineered chimeric antigen receptor (CAR) T cells in other blood neoplasms have paved the way for the development of immune cell-based therapies for adverse genetic risk AML. Among these, adoptive cell immunotherapies with single/multiple CAR-T cells, CAR-natural killer (NK) cells, cytokine-induced killer cells (CIK), and NK cells are subjects of ongoing clinical trials. On the other hand, allogeneic hematopoietic stem cell transplantation (allo-HSCT) still represents the only curative option for adverse genetic risk AML patients. Unfortunately, high relapse rates (above 50%) and associated dismal outcomes (reported survival ~10–20%) even question the role of current allo-HSCT protocols and emphasize the urgency of adopting novel effective transplant strategies. We have recently demonstrated that haploidentical allo-HSCT combined with regulatory and conventional T cells adoptive immunotherapy (Treg-Tcon haplo-HSCT) is able to overcome disease-intrinsic chemoresistance, prevent leukemia-relapse, and improve survival of adverse genetic risk AML patients. In this Perspective, we briefly review the recent advancements with immune cell-based strategies against adverse genetic risk AML and discuss how such approaches could favorably impact on patients’ outcomes.

PHF6 Mutations in Hematologic Malignancies

Next generation sequencing has uncovered several genes with associated mutations in hematologic malignancies that can serve as potential biomarkers of disease. Keeping abreast of these genes is therefore of paramount importance in the field of hematology. This review focuses on PHF6, a highly conserved epigenetic transcriptional regulator that is important for neurodevelopment and hematopoiesis. PHF6 serves as a tumor suppressor protein, with PHF6 mutations and deletions often implicated in the development of T-lymphoblastic leukemia and less frequently in acute myeloid leukemia and other myeloid neoplasms. PHF6 inactivation appears to be an early event in T-lymphoblastic leukemogenesis, requiring cooperating events, including NOTCH1 mutations or overexpression of TLX1 and TLX3 for full disease development. In contrast, PHF6 mutations tend to occur later in myeloid malignancies, are frequently accompanied by RUNX1 mutations, and are often associated with disease progression. Moreover, PHF6 appears to play a role in lineage plasticity within hematopoietic malignancies, with PHF6 mutations commonly present in mixed phenotype acute leukemias with a predilection for T-lineage marker expression. Due to conflicting data, the prognostic significance of PHF6 mutations remains unclear, with a subset of studies showing no significant difference in outcomes compared to malignancies with wild-type PHF6, and other studies showing inferior outcomes in certain patients with mutated PHF6. Future studies are necessary to elucidate the role PHF6 plays in development of T-lymphoblastic leukemia, progression of myeloid malignancies, and its overall prognostic significance in hematopoietic neoplasms.

Molecular Characterization and Clinical Treatment of Acute Myeloid Leukemia (AML) and Myelodysplastic Syndromes (MDS) Patients With TP53 Mutation

BACKGROUND

Mutations in TP53 in myeloid neoplasms patients have been associated with poor prognosis. Effective treatments to these patients remain unclear.

PATIENTS AND METHODS

In this study, we retrospectively analyzed diagnostic and outcomes of 31 Acute Myeloid leukemia (AML) and 9 Myelodysplastic syndromes (MDS) patients with TP53 mutation at our hospital from September 2015 to October 2020.

RESULTS

A total of 42 variants (28 unique variants) in the coding region of TP53 gene were identified, and most were missense mutation (34 of 42, 81%). The median overall survival (OS) was 8 months for the AML patients (1-32 months) and 7 months for the MDS patients (3-27 months). There were 35 and 13 patients underwent frontline chemical therapy and Allo-HSCT, respectively. The overall response rate was 45.3% (16/35) for the frontline treatment. There was no significant difference between intensive and low-intensity regimens on either response to the frontline treatment (P = .255) or overall survival (P = .078). Patients, who achieved complete or partial remission at the frontline treatment, presented a higher survival than patients in non-remission, no matter transplant or not.

CONCLUSION

This study corroborates that improving the response to the first-line treatment could prolong the survival of myeloid neoplasms patients with TP53 mutation. Allo-HSCT could be a curative option for patients with TP53 mutation, when in complete remission during the first-line treatment.

Precision oncology in AML: validation of the prognostic value of the knowledge bank approach and suggestions for improvement

Recently, a novel knowledge bank (KB) approach to predict outcomes of individual patients with acute myeloid leukemia (AML) was developed using unbiased machine learning. To validate its prognostic value, we analyzed 1612 adults with de novo AML treated on Cancer and Leukemia Group B front-line trials who had pretreatment clinical, cytogenetics, and mutation data on 81 leukemia/cancer-associated genes available. We used receiver operating characteristic (ROC) curves and the area under the curve (AUC) to evaluate the predictive values of the KB algorithm and other risk classifications. The KB algorithm predicted 3-year overall survival (OS) probability in the entire patient cohort (AUC_KB = 0.799), and both younger (< 60 years) (AUC_KB = 0.747) and older patients (AUC_KB = 0.770). The KB algorithm predicted non-remission death (AUC_KB = 0.860) well but was less accurate in predicting relapse death (AUC_KB = 0.695) and death in first complete remission (AUC_KB = 0.603). The KB algorithm’s 3-year OS predictive value was higher than that of the 2017 European LeukemiaNet (ELN) classification (AUC_2017ELN = 0.707, p < 0.001) and 2010 ELN classification (AUC_2010ELN = 0.721, p < 0.001) but did not differ significantly from that of the 17-gene stemness score (AUC_17-gene = 0.732, p = 0.10). Analysis of additional cytogenetic and molecular markers not included in the KB algorithm revealed that taking into account atypical complex karyotype, infrequent recurrent balanced chromosome rearrangements and mutational status of the SAMHD1, AXL and NOTCH1 genes may improve the KB algorithm. We conclude that the KB algorithm has a high predictive value that is higher than those of the 2017 and 2010 ELN classifications. Inclusion of additional genetic features might refine the KB algorithm.

CT classification of acute myeloid leukemia with pulmonary infiltration

PURPOSE

To characterize and categorize the CT findings of pulmonary leukemic infiltration (PLI) in patients with acute myeloid leukemia (AML).

MATERIALS AND METHODS

Among 435 patients with AML, 20 patients with PLI were retrospectively selected, and clinical characteristics and CT findings were analyzed. PLI was categorized into four patterns according to CT findings: type A, multiple nodules and/or masses; type B, bilateral perihilar airspace opacities (GGA or consolidation) without any nodules or masses; type C, mixture of type A and B; and type D, PLI without visible abnormal lung opacity. The difference in overall survival among four CT patterns was also examined.

RESULTS

The frequency of complex karyotypes was higher in AML patients with PLI than in whole AML patients. Percentages of patients with CT findings of type A, B, C, and D were 35%, 20%, 35%, and 10%, respectively. There was a clear difference in the localization of opacities according to the type of infiltrates, i.e., nodules/masses were mainly detected in the lower/peripheral portion. Conversely, GGA was mainly located in the upper/central portion. The median overall survival from diagnosis of PLI was 262 days (range 12-1148). The CT pattern was not significantly associated with survival (p = 0.3), with the exception of patients with type C tending to have significantly better outcomes compared to patients with type B (p = 0.05).

CONCLUSION

This classification can contribute in accurate non-invasive diagnosis and possibly in the estimation of prognosis.

Chromosomal Instability in Acute Myeloid Leukemia

Chromosomal instability (CIN), the increasing rate in which cells acquire new chromosomal alterations, is one of the hallmarks of cancer. Many studies highlighted CIN as an important mechanism in the origin, progression, and relapse of acute myeloid leukemia (AML). The ambivalent feature of CIN as a cancer-promoting or cancer-suppressing mechanism might explain the prognostic variability. The latter, however, is described in very few studies. This review highlights the important CIN mechanisms in AML, showing that CIN signatures can occur largely in all the three major AML types (de novo AML, secondary-AML, and therapy-related-AML). CIN features in AML could also be age-related and reflect the heterogeneity of the disease. Although most of these abnormalities show an adverse prognostic value, they also offer a strong new perspective on personalized therapy approaches, which goes beyond assessing CIN in vitro in patient tumor samples to predict prognosis. Current and emerging AML therapies are exploring CIN to improve AML treatment, which includes blocking CIN or increasing CIN beyond the limit threshold to induce cell death. We argue that the characterization of CIN features, not included yet in the routine diagnostic of AML patients, might provide a better stratification of patients and be extended to a more personalized therapeutic approach.

Cytogenetic and mutational analysis and outcome assessment of a cohort of 284 children with de novo acute myeloid leukemia reveal complex karyotype as an adverse risk factor for inferior survival

Background

Acute myeloid leukemia (AML) is rare in children. Although complex karyotype (CK) defined as ≥ 3 cytogenetic abnormalities is an adverse risk factor in adult AML, its prognostic impact on childhood AML remains to be determined.

Results

We studied the prevalence, cytogenetic and mutational features, and outcome impact of CK in a cohort of 284 Chinese children with de novo AML. Thirty-four (12.0%) children met the criteria for CK-AML with atypical CK being more frequent than typical CK featured with -5/5q-, -7/7q-, and/or 17p aberration. Mutational prevalence was low and co-occurrence mutants were uncommon. Children with CK-AML showed shorter overall survival (OS) (5-year OS: 26.7 ± 10.6% vs. 37.5 ± 8.6%, p = 0.053) and event-free survival (EFS) (5-year EFS: 26.7 ± 10.6% vs. 38.8 ± 8.6%, p = 0.039) compared with those with intermediate-risk genetics. Typical CK tended to correlate with a decreased OS than atypical CK (5-year OS: 0 vs. 33 ± 12.7%.; p = 0.084), and CK with ≥ 5 cytogenetic aberrations was associated with an inferior survival compared with CK with ≤ 4 aberrations (5-year OS: 13.6 ± 11.7% vs. 50.0 ± 18.6%; p = 0.040; 5-year EFS: 13.6 ± 11.7% vs. 50.0 ± 18.6%; p = 0.048).

Conclusion

Our results demonstrate CK as an adverse risk factor for reduced survival in childhood AML. Our findings shed light on the cytogenetic and mutational profile of childhood CK-AML and would inform refinement of risk stratification in childhood AML to improve outcomes.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13039-021-00547-0.

Novel Targeted Therapeutics in Acute Myeloid Leukemia: an Embarrassment of Riches

PURPOSE OF REVIEW

Acute myeloid leukemia (AML) is an aggressive malignancy of the bone marrow that has a poor prognosis with traditional cytotoxic chemotherapy, especially in elderly patients. In recent years, small molecule inhibitors targeting AML-associated IDH1, IDH2, and FLT3 mutations have been FDA approved. However, the majority of AML cases do not have a targetable mutation. A variety of novel agents targeting both previously untargetable mutations and general pathways in AML are currently being investigated. Herein, we review selected new targeted therapies currently in early-phase clinical investigation in AML.

RECENT FINDINGS

The DOT1L inhibitor pinometostat in KMT2A-rearranged AML, the menin inhibitors KO-539 and SYNDX-5613 in KMT2Ar and NPM1-mutated AML, and the mutant TP53 inhibitor APR-246 are examples of novel agents targeting specific mutations in AML. In addition, BET inhibitors, polo-like kinase inhibitors, and MDM2 inhibitors are promising new drug classes for AML which do not depend on the presence of a particular mutation. AML remains in incurable disease for many patients but advances in genomics, epigenetics, and drug discovery have led to the development of many potential novel therapeutic agents, many of which are being investigated in ongoing clinical trials. Additional studies will be necessary to determine how best to incorporate these novel agents into routine clinical treatment of AML.