Mutational landscape of AML with normal cytogenetics: biological and clinical implications

High Expression of GPR183 Predicts Poor Survival in Cytogenetically Normal Acute Myeloid Leukemia

Acute myeloid leukemia (AML) with a normal karyotype (CN-AML) constitutes approximately 50% of all AML cases, presenting significant prognostic variability, and highlighting the urgent need for the identification of novel molecular biomarkers. In this study, we systematically assessed GPR183 expression levels using qRT-PCR in our clinical follow-up study which included 283 CN-AML patients. Using Kaplan-Meier analysis, we found that patients with high GPR183 expression levels exhibited significantly worse overall survival (OS) (P = 0.046) and event-free survival (EFS) (P = 0.030) compared to those with low GPR183 expression. Comprehensive univariate and multivariate Cox regression analyses confirmed that GPR183 expression is a prognostic factor for OS and EFS (P < 0.05). To further validate these findings, we analyzed an independent cohort of 104 CN-AML patients from the GSE71014 dataset, corroborating our primary results, and indicating that high GPR183 expression is associated with poorer survival outcomes. Additionally, RNA-seq data from the GSE71014 dataset were analyzed by Gene Set Enrichment Analysis (GSEA). The results suggested that GPR183 may influence disease progression through the activation of the "TNFa Signaling Via NF-κB" pathway. Collectively, these findings suggested that GPR183 could serve as a valuable prognostic biomarker in CN-AML, offering insights into the underlying mechanisms of disease progression.

CAR-NK cell therapy in AML: Current treatment, challenges, and advantage

Over the last decade, discovery of novel therapeutic method has been attention by the researchers and has changed the therapeutic perspective of hematological malignancies. Although NK cell play a pivotal role in the elimination of abnormal and cancerous cells, there are evidence that NK cell are disarm in hematological malignancy. Chimeric antigen receptor NK (CAR-NK) cell therapy, which includes the engineering of NK cells to detect tumor-specific antigens and, as a result, clear of cancerous cells, has created various clinical advantage for several human malignancies treatment. In the current review, we summarized NK cell dysfunction and CAR-NK cell based immunotherapy to treat AML patient.

A blastic plasmacytoid dendritic cell neoplasm-like immunophenotype is negatively associated with CEBPA bZIP mutation and predicts unfavorable prognosis in acute myeloid leukemia

Blastic plasmacytoid dendritic cell neoplasm (BPDCN) is a rare and aggressive myeloid malignancy which characteristically expresses an atypical phenotype including CD123+, CD56+, and CD4+. We are aimed to investigate the clinical and prognostic characteristics of AML patients exhibiting BPDCN-like immunophenotype and provide additional insights for risk stratification of AML. A total of 241 newly diagnosed AML patients were enrolled in this retrospective study and categorized into BPDCN-like positive (n = 125)/negative (n = 116) groups, determined by the present with CD123+ along with either CD56+ or CD4+, or both. Subsequently, an analysis was conducted to examine the general clinical characteristics, genetic profiles, and prognosis of the two respective groups. Patients with BPDCN-like immunophenotype manifested higher frequencies of acute myelomonocytic leukemia and acute monoblastic leukemia. Surprisingly, the presence of the BPDCN-like immunophenotype exhibited an inverse relationship with CEBPA bZIP mutation. Notably, patients with BPDCN-like phenotype had both worse OS and EFS compared to those without BPDCN-like phenotype. In the CN-AML subgroups, the BPDCN-like phenotype was associated with worse EFS. Similarly, a statistically significant disparity was observed in both OS and EFS within the favorable-risk subgroup, while only OS was significant within the adverse-risk subgrouMoreover, patients possessing favorable-risk genetics without BPDCN-like phenotype had the longest survival, whereas those who had both adverse-risk genetics and BPDCN-like phenotype exhibited the worst survival. Our study indicated that BPDCN-like phenotype negatively associated with CEBPA bZIP mutation and revealed a significantly poor prognosis in AML. Moreover, the 2022 ELN classification, in combination with the BPDCN-like phenotype, may better distinguish between different risk groups.

Modeling early treatment response in AML from cell-free tumor DNA

Monitoring disease response after intensive chemotherapy for acute myeloid leukemia (AML) currently requires invasive bone marrow biopsies, imposing a significant burden on patients. In contrast, cell-free tumor DNA (ctDNA) in peripheral blood, carrying tumor-specific mutations, offers a less-invasive assessment of residual disease. However, the relationship between ctDNA levels and bone marrow blast kinetics remains unclear. We explored this in 10 AML patients with NPM1 and IDH2 mutations undergoing initial chemotherapy. Comparison of mathematical mixed-effect models showed that (1) inclusion of blast cell death in the bone marrow, (2) transition of ctDNA to peripheral blood, and (3) ctDNA decay in peripheral blood describes kinetics of blast cells and ctDNA best. The fitted model allows prediction of residual bone marrow blast content from ctDNA, and its scaling factor, representing clonal heterogeneity, correlates with relapse risk. Our study provides precise insights into blast and ctDNA kinetics, offering novel avenues for AML disease monitoring.

Pathogenic mutation hotspots in protein kinase domain structure

Control of eukaryotic cellular function is heavily reliant on the phosphorylation of proteins at specific amino acid residues, such as serine, threonine, tyrosine, and histidine. Protein kinases that are responsible for this process comprise one of the largest families of evolutionarily related proteins. Dysregulation of protein kinase signaling pathways is a frequent cause of a large variety of human diseases including cancer, autoimmune, neurodegenerative, and cardiovascular disorders. In this study, we mapped all pathogenic mutations in 497 human protein kinase domains from the ClinVar database to the reference structure of Aurora kinase A (AURKA) and grouped them by the relevance to the disease type. Our study revealed that the majority of mutation hotspots associated with cancer are situated within the catalytic and activation loops of the kinase domain, whereas non-cancer-related hotspots tend to be located outside of these regions. Additionally, we identified a hotspot at residue R371 of the AURKA structure that has the highest number of exclusively non-cancer-related pathogenic mutations (21) and has not been previously discussed.

Identification of DUSP7 as an RNA Marker for Prognostic Stratification in Acute Myeloid Leukemia: Evidence from Large Population Cohorts

Background

The problem of prognostic stratification in acute myeloid leukemia (AML) patients still has limitations.

Methods

The expression profile data and clinical features of AML patients were obtained from multiple publicly available sources, including GSE71014, TCGA-LAML, and TARGET-AML. Single-cell analysis was performed using the TISCH project. All the analysis was conducted in the R software.

Results

In our study, three public AML cohorts, GSE71014, TARGET-AML, and TCGA-AML, were selected. Then, we identified the prognosis-related molecules through bioinformatic analysis. Finally, the DUSP7 was noticed as a risk factor for AML patients, which has not been reported previously. Biological enrichment analysis and immune-related analysis were performed to illustrate the role of DUSP7 in AML. Single-cell analysis indicated that the DUSP7 was widely distributed in various cells, especially in monocyte/macrophages and malignant. Following this, a prognosis model based on DUSP7-derived genes was constructed, which showed a good prognosis prediction ability in all cohorts.

Conclusions

Our results preliminarily reveal the role and potential mechanism of DUSP7 in AML, providing direction for future research.

Ubiquitin-specific peptidase 10, a deubiquitinating enzyme: Assessing its role in tumor prognosis and immune response

Ubiquitin-specific peptidase 10 (USP10) is a member of the ubiquitin-specific protease family that removes the ubiquitin chain from ubiquitin-conjugated protein substrates. We performed a literature search to evaluate the structure and biological activity of USP10, summarize its role in tumorigenesis and tumor progression, and discuss how USP10 may act as a tumor suppressor or a tumor-promoting gene depending on its mechanism of action. Subsequently, we elaborated further on these results through bioinformatics analysis. We demonstrated that abnormal expression of USP10 is related to tumorigenesis in various types of cancer, including liver, lung, ovarian, breast, prostate, and gastric cancers and acute myeloid leukemia. Meanwhile, in certain cancers, increased USP10 expression is associated with tumor suppression. USP10 was downregulated in kidney renal clear cell carcinoma (KIRC) and associated with reduced overall survival in patients with KIRC. In contrast, USP10 upregulation was associated with poor prognosis in head and neck squamous cell carcinoma (HNSC). In addition, we elucidated the novel role of USP10 in the regulation of tumor immunity in KIRC and HNSC through bioinformatics analysis. We identified several signaling pathways to be significantly associated with USP10 expression, such as ferroptosis, PI3K/AKT/mTOR, TGF-β, and G2/M checkpoint. In summary, this review outlines the role of USP10 in various forms of cancer, discusses the relevance of USP10 inhibitors in anti-tumor therapies, and highlights the potential function of USP10 in regulating the immune responses of tumors.

Evaluation of the Stellae-123 prognostic gene expression signature in acute myeloid leukemia

Risk stratification in acute myeloid leukemia (AML) has been extensively improved thanks to the incorporation of recurrent cytogenomic alterations into risk stratification guidelines. However, mortality rates among fit patients assigned to low or intermediate risk groups are still high. Therefore, significant room exists for the improvement of AML prognostication. In a previous work, we presented the Stellae-123 gene expression signature, which achieved a high accuracy in the prognostication of adult patients with AML. Stellae-123 was particularly accurate to restratify patients bearing high-risk mutations, such as ASXL1, RUNX1 and TP53. The intention of the present work was to evaluate the prognostic performance of Stellae-123 in external cohorts using RNAseq technology. For this, we evaluated the signature in 3 different AML cohorts (2 adult and 1 pediatric). Our results indicate that the prognostic performance of the Stellae-123 signature is reproducible in the 3 cohorts of patients. Additionally, we evidenced that the signature was superior to the European LeukemiaNet 2017 and the pediatric clinical risk scores in the prediction of survival at most of the evaluated time points. Furthermore, integration with age substantially enhanced the accuracy of the model. In conclusion, Stellae-123 is a reproducible machine learning algorithm based on a gene expression signature with promising utility in the field of AML.

ADAMTS14, ARHGAP22, and EPDR1 as potential novel targets in acute myeloid leukaemia

Acute myeloid leukaemia (AML) is a blood cancer with a heterogeneous genomic landscape. This study aimed to mine bioinformatics data generated by RNA sequencing to unveil an AML case transcriptome profile and identify novel therapeutic targets and markers. In this study, we have determined the transcriptomic profile and analysed gene variants of an AML patient at the time of diagnosis and validated some genes by quantitative reverse transcriptase polymerase chain reaction. ADAMTS14, ARHGAP22, and ependymin-related protein 1 (EPDR1) were markedly upregulated compared to the corresponding control. In addition, novel exonic single-nucleotide and insertion/deletion variants were identified in these genes. Hence, ADAMTS14, ARHGAP22, and EPDR1 can be proposed as potential novel targets in AML, and their exact roles should be further explored.

Acute Myeloid Leukemia-Related Proteins Modified by Ubiquitin and Ubiquitin-like Proteins

Acute myeloid leukemia (AML), the most common form of an acute leukemia, is a malignant disorder of stem cell precursors of the myeloid lineage. Ubiquitination is one of the post-translational modifications (PTMs), and the ubiquitin-like proteins (Ubls; SUMO, NEDD8, and ISG15) play a critical role in various cellular processes, including autophagy, cell-cycle control, DNA repair, signal transduction, and transcription. Also, the importance of Ubls in AML is increasing, with the growing research defining the effect of Ubls in AML. Numerous studies have actively reported that AML-related mutated proteins are linked to Ub and Ubls. The current review discusses the roles of proteins associated with protein ubiquitination, modifications by Ubls in AML, and substrates that can be applied for therapeutic targets in AML.

The Bone Marrow Microenvironment Mechanisms in Acute Myeloid Leukemia

Bone marrow (BM) is a highly complex tissue that provides important regulatory signals to orchestrate hematopoiesis. Resident and transient cells occupy and interact with some well characterized niches to produce molecular and cellular mechanisms that interfere with differentiation, migration, survival, and proliferation in this microenvironment. The acute myeloid leukemia (AML), the most common and severe hematological neoplasm in adults, arises and develop in the BM. The osteoblastic, vascular, and reticular niches provide surface co-receptors, soluble factors, cytokines, and chemokines that mediate important functions on hematopoietic cells and leukemic blasts. There are some evidences of how AML modify the architecture and function of these three BM niches, but it has been still unclear how essential those modifications are to maintain AML development. Basic studies and clinical trials have been suggesting that disturbing specific cells and molecules into the BM niches might be able to impair leukemia competencies. Either through niche-specific molecule inhibition alone or in combination with more traditional drugs, the bone marrow microenvironment is currently considered the potential target for new strategies to treat AML patients. This review describes the cellular and molecular constitution of the BM niches under healthy and AML conditions, presenting this anatomical compartment by a new perspective: as a prospective target for current and next generation therapies.

Prognostic significance of ferroptosis-related genes and their methylation in AML

BACKGROUND

Ferroptosis involves in the development and therapeutic response of various types of tumors. This study aims to explore ferroptosis-related prognostic genes that could further accurately stratify AML patients.

METHODS

We investigated the prognosis significance of ferroptosis-related genes in AML by Univariate and multivariate Cox proportional hazards regression analyses. With the methylation data of TCGA samples, we looked for methylation sites associated with prognostic genes and compared the correlation between methylation and mRNA expression. R software and 'edgeR' packages were used to identify the DEGs between the high-and-low-risk groups divided by the FRPGs prognosis model and then run GO enrichment, KEGG pathway, and PPI network.

RESULTS

We found a prognostic risk model that included AKR1C2 and SOCS1 predicted outcomes in AML patients. Methylation analysis showed that AKR1C2 and SOCS1 are negatively regulated by their methylation, leading to their low expression in AML patients. Besides, both decreased SOCS1 expression and hypermethylation predicted favorable OS and PFS in AML patients. Finally, this prognostic risk model exhibited a close correlation with several clinical features, especially with age (P=0.005), cytogenetic type (P=0.031), risk_cytogenetic (P=0.001), and risk_molecular (P<0.001). Functional enrichment analysis showed that DEGs are most enriched in the regulation of cell death and the PI3K-Akt signaling pathway.

CONCLUSION

AKR1C2 and SOCS1 are promising biomarkers for predicting prognosis in patients with AML.

Type F mutation of nucleophosmin 1 Acute Myeloid Leukemia: A tale of disorder and aggregation

Protein aggregation is suggested as a reversible, wide-spread physiological process used by cells to regulate their growth and adapt to different stress conditions. Nucleophosmin 1(NPM1) protein is an abundant multifunctional nucleolar chaperone and its gene is the most frequently mutated in Acute Myeloid Leukemia (AML) patients. So far, the role of NPM1 mutations in leukemogenesis has remained largely elusive considering that they have the double effect of unfolding the C-terminal domain (CTD) and delocalizing the protein in the cytosol (NPM1c+). This mislocalization heavily impacts on cell cycle regulation. Our recent investigations unequivocally demonstrated an amyloid aggregation propensity introduced by AML mutations. Herein, employing complementary biophysical assays, we have characterized a N-terminal extended version of type F AML mutation of CTD and proved that it is able to form assemblies with amyloid character and fibrillar morphology. The present study represents an additional phase of knowledge to deepen the roles exerted by different types of cytoplasmatic NPM1c+ forms to develop in the future potential therapeutics for their selective targeting.

Whole genome, exon mutation and transcriptomic profiling of acute myeloid leukemia: A case report

The present study aimed to observe previously unidentified gene mutation and expression profiles associated with acute myeloid leukemia (AML) at the individual level, based on the blood samples of a father-son pair. Genomic DNA and RNA samples from blood serum were collected. Whole-genome sequencing (WGS) and whole-exome sequencing (WES), as well as mRNA sequencing of the son, were performed. For the father's sample, a total of 3,897,164 single nucleotide polymorphisms (SNPs) and 780,834 insertion and deletions (indels) were identified. Regarding amino acid translation, there were 11,316 non-synonymous, 12 stop-loss, 12,033 synonymous, 92 stop-gain SNPs, 63 frameshift insertions, 73 frameshift deletions, 242 non-frameshift insertions, 248 non-frameshift deletions, four stop-gains and two stop-loss for indel variants. Among the AML-related genes that had been previously identified, 14 genes were found in the father's exon region. For WES of the son's DNA, 96,639 SNPs were identified, including 10,504 non-synonymous SNPs. Seven mutant genes were found in sons' exon region compared with 121 AML-related genes. Based on the transcriptomic sequencing, there were 54 differentially expressed mRNAs, including 31 upregulated and 23 downregulated mRNAs. In the exon region, 10,072 SNPs were detected, and different types of alternative splicing in the son's sample were observed. Overall, whole genome, exon mutation and transcriptomic profiling of the present two patients with AML may provide a new insight into the molecular events governing the development of AML.

IL-37 Was Involved in Progress of Acute Myeloid Leukemia Through Regulating IL-6 Expression

Background

Interleukin-37, which was discovered in 2000, is a natural suppressor of immune and inflammatory responses. Recent studies reported that IL-37 was abnormally expressed in several tumor patients, including those with hepatocellular carcinoma, gastric cancer, lung cancer, colon cancer, epithelial ovarian cancer, and multiple myeloma. However, the expression and potential function of IL-37 in leukemia remain unknown.

Objective

The aim of this study was to evaluate IL-37 as a prognostic factor and its possible mechanism of action.

Methods

Polymerase chain reaction products were analyzed by agarose gel electrophoresis and were purified and subsequently sequenced by a genetic testing laboratory. Human PBMC was purified from whole blood samples by using Ficoll-Paque PLUS. The concentrations of human IL-37 and human IL-6 were measured using enzyme-linked immunosorbent assay (ELISA) kits.

Results

IL-37, especially isoform b and d, was expressed in the bone marrow of AML, CML, ALL, and CLL. Importantly, IL-37 expression was downregulated in newly diagnosed AML patients and restored in patients in complete remission. Moreover, a significant association was found between IL-37 expression and NPM1 mutation or possible prognosis evaluated by karyotype and gene mutation. Further analysis revealed that IL-37 expression was negatively correlated with IL-6 expression. With regard to the mechanism, recombinant human IL-37 could suppress IL-6 expression stimulated by LPS in PBMC of AML patients.

Conclusion

Our study suggested that IL-37 may be an important prognostic factor in AML and is involved in AML via the IL-6 signaling pathway, indicating that IL-37 is an innovative research strategy for AML pathogenesis and therapy.

[Expression of circ-KEL in acute myeloid leukemia and its regulatory mechanisms in leukemic cells]

Objective: To explore the expression of circ-KEL in patients with acute myeloid leukemia (AML) and the effect and mechanism of circ-KEL on leukemic cells. Methods: The expression of circ-KEL was detected by quantitative real-time polymerase chain reaction in bone marrow mononuclear cells collected from 116 patients with AML and 40 healthy donors. The correlation of circ-KEL expression with the clinical characteristics of patients with AML was further systematically analyzed. The modulations among circ-KEL, miR-335-5p, and LRG1 were predicted through bioinformatics analysis and validated by dual luciferase assay. Cell proliferation and apoptosis were detected using CCK8 and flow cytometry. Results: The expression of circ-KEL was significantly elevated in patients with AML compared with the healthy controls (Relative expression level, -Δct, AML: -7.117±1.831; control: -8.669±1.771, P<0.001) . Moreover, patients with high circ-KEL expression have significantly worse overall survival. The level of circ-KEL in patients with AML was downregulated after chemo-treatment. In addition, circ-KEL could serve as the sponge of miR-335-5p and regulate LRG1. Bioinformatics analysis showed that miR-335-5p correlates with good prognosis and was negatively associated with LRG1. LRG1 could promote cell proliferation and inhibit cell apoptosis. Our results also exhibited the higher expression of LRG1 in patients with AML. Moreover, circ-KEL exerted functional effects via sponging miR-335-5p and regulating LRG1. Conclusion: circ-KEL expresses highly in patients with AML and correlates with poor prognosis, suggesting its important role in the genesis and progress of AML.

Mouse Models of Myeloid Malignancies

Mouse models of human myeloid malignancies support the detailed and focused investigation of selected driver mutations and represent powerful tools in the study of these diseases. Carefully developed murine models can closely recapitulate human myeloid malignancies in vivo, enabling the interrogation of a number of aspects of these diseases including their preclinical course, interactions with the microenvironment, effects of pharmacological agents, and the role of non-cell-autonomous factors, as well as the synergy between co-occurring mutations. Importantly, advances in gene-editing technologies, particularly CRISPR-Cas9, have opened new avenues for the development and study of genetically modified mice and also enable the direct modification of mouse and human hematopoietic cells. In this review we provide a concise overview of some of the important mouse models that have advanced our understanding of myeloid leukemogenesis with an emphasis on models relevant to clonal hematopoiesis, myelodysplastic syndromes, and acute myeloid leukemia with a normal karyotype.

A modular and controllable T cell therapy platform for acute myeloid leukemia

Targeted T cell therapy is highly effective in disease settings where tumor antigens are uniformly expressed on malignant cells and where off-tumor on-target-associated toxicity is manageable. Although acute myeloid leukemia (AML) has in principle been shown to be a T cell-sensitive disease by the graft-versus-leukemia activity of allogeneic stem cell transplantation, T cell therapy has so far failed in this setting. This is largely due to the lack of target structures both sufficiently selective and uniformly expressed on AML, causing unacceptable myeloid cell toxicity. To address this, we developed a modular and controllable MHC-unrestricted adoptive T cell therapy platform tailored to AML. This platform combines synthetic agonistic receptor (SAR) -transduced T cells with AML-targeting tandem single chain variable fragment (scFv) constructs. Construct exchange allows SAR T cells to be redirected toward alternative targets, a process enabled by the short half-life and controllability of these antibody fragments. Combining SAR-transduced T cells with the scFv constructs resulted in selective killing of CD33⁺ and CD123⁺ AML cell lines, as well as of patient-derived AML blasts. Durable responses and persistence of SAR-transduced T cells could also be demonstrated in AML xenograft models. Together these results warrant further translation of this novel platform for AML treatment.

Real-Time Molecular Monitoring in Acute Myeloid Leukemia With Circulating Tumor DNA

The clonal evolution of acute myeloid leukemia (AML), an oligoclonal hematological malignancy, is driven by a plethora of cytogenetic abnormalities, gene mutations, abnormal epigenetic patterns, and aberrant gene expressions. These alterations in the leukemic blasts promote clinically diverse manifestations with common characteristics of high relapse and drug resistance. Defining and real-time monitoring of a personalized panel of these predictive genetic biomarkers is rapidly being adapted in clinical setting for diagnostic, prognostic, and therapeutic decision-making in AML. A major challenge remains the frequency of invasive biopsy procedures that can be routinely performed for monitoring of AML disease progression. Moreover, a single-site biopsy is not representative of the tumor heterogeneity as it is spatially and temporally constrained and necessitates the understanding of longitudinal and spatial subclonal dynamics in AML. Hematopoietic cells are a major contributor to plasma cell-free DNA, which also contain leukemia-specific aberrations as the circulating tumor-derived DNA (ctDNA) fraction. Plasma cell-free DNA analysis holds immense potential as a minimally invasive tool for genomic profiling at diagnosis as well as clonal evolution during AML disease progression. With the technological advances and increasing sensitivity for detection of ctDNA, both genetic and epigenetic aberrations can be qualitatively and quantitatively evaluated. However, challenges remain in validating the utility of liquid biopsy tools in clinics, and universal recommendations are still awaited towards reliable diagnostics and prognostics. Here, we provide an overview on the scope of ctDNA analyses for prognosis, assessment of response to treatment and measurable residual disease, prediction of disease relapse, development of acquired resistance and beyond in AML.

RNA sequencing-based identification of potential targets in acute myeloid leukemia: A case report

Acute myeloid leukemia (AML) refers to heterogenous types of blood cancer which possess a complicated genomic landscape, and multiple novel mutational alterations are frequently being reported. Herein, a case report of a 37-year old AML patient is presented, who was diagnosed following laboratory investigation after admission. The patient had thrombocytopenia, and three consecutive blast counts of 40, 30 and 41%, respectively. A blood sample was collected for whole-genome RNA sequencing to understand the transcriptomic profile at the time of diagnosis and compared with a matched female control. Gene expression was quantified using the RSEM software package. Bioinformatics analysis revealed a significant number of differentially expressed genes in the patient, suggesting a marked change in the transcriptomic landscape in this patient. By mining the bioinformatics data and screening the highly expressed genes with ≥80% probability of gene expression, four novel genes were highlighted that may serve as potential future targets in AML patients; Rh associated glycoprotein, succinate receptor 1, transmembrane-4 L-six family member-1 and ADGRA3, although further validation of their value is required.

Secondary chronic myeloid leukemia following acute myeloid leukemia treated with autologous hematopoietic stem cell transplantation: a case report

OBJECTIVE

Acute myeloid leukemia (AML) is a hematopoietic stem cell malignancy and the most common type of leukemia, with the 5-year relative survival rate of 19% in Europe. Chronic myeloid leukemia (CML) is a slowly progressive clonal malignant disease, and a myeloproliferative disorder which is derived from biphasic hematopoietic stem cells but driven by progenitor cells. AML following CML is common, which can be caused by an antecedent myeloid malignancy, leukemogenic therapy, or without an identifiable prodrome or exposure to cytotoxic agents. However, the case of secondary chronic myeloid leukemia following acute myeloid leukemia treated with autologous hematopoietic stem cell transplantation is rare.

METHODS

Here we report a unique case of secondary CML after AML treated by chemotherapy and autologous peripheral blood stem cell transplantation. The 34-year-old male was diagnosed with AML subtype M5b according to clinical features in 2011. The patient was treated with the MAE program (mitoxantrone, cytosine arabinoside, etoposide) for two courses, followed by the IAE program (idarubicin, cytosine arabinoside, etoposide) and cytosine arabinoside for consolidation chemotherapy. An autologous hematopoietic stem cell transplantation with prophylactic intrathecal methotrexate cytarabine and dexamethasone was initiated.

RESULTS

Subsequently, the patient achieved complete remission in 2012. After 4 years, the patient presented with leukocyte elevation of more than 4 months, and then was diagnosed with secondary CML. Based on this diagnosis, and with respect to the patient's severely compromised overall condition, tyrosine kinase inhibitors (TKI) therapy was conducted in 2016. The patient achieved, and continue to be in, complete remission.

CONCLUSIONS

The case expands the understanding of secondary CML and emphasizes the importance of oncological vigilance in patients with secondary CML after AML therapy.

Nucleophosmin in Its Interaction with Ligands

Nucleophosmin (NPM1) is a mainly nucleolar protein that shuttles between nucleoli, nucleoplasm and cytoplasm to fulfill its many functions. It is a chaperone of both nucleic acids and proteins and plays a role in cell cycle control, centrosome duplication, ribosome maturation and export, as well as the cellular response to a variety of stress stimuli. NPM1 is a hub protein in nucleoli where it contributes to nucleolar organization through heterotypic and homotypic interactions. Furthermore, several alterations, including overexpression, chromosomal translocations and mutations are present in solid and hematological cancers. Recently, novel germline mutations that cause dyskeratosis congenita have also been described. This review focuses on NPM1 interactions and inhibition. Indeed, the list of NPM1 binding partners is ever-growing and, in recent years, many studies contributed to clarifying the structural basis for NPM1 recognition of both nucleic acids and several proteins. Intriguingly, a number of natural and synthetic ligands that interfere with NPM1 interactions have also been reported. The possible role of NPM1 inhibitors in the treatment of multiple cancers and other pathologies is emerging as a new therapeutic strategy.

Genomic analysis of biomarkers related to the prognosis of acute myeloid leukemia

Acute myeloid leukemia (AML) is the most common childhood cancer and is a major cause of morbidity among adults with hematologic malignancies. Several novel genetic alterations, which target critical cellular pathways, including alterations in lymphoid development-regulating genes, tumor suppressors and oncogenes that contribute to leukemogenesis, have been identified. The present study aimed to identify molecular markers associated with the occurrence and poor prognosis of AML. Information on these molecular markers may facilitate prediction of clinical outcomes. Clinical data and RNA expression profiles of AML specimens from The Cancer Genome Atlas database were assessed. Mutation data were analyzed and mapped using the maftools package in R software. Kyoto Encyclopedia of Genes and Genomes, Reactome and Gene Ontology analyses were performed using the clusterProfiler package in R software. Furthermore, Kaplan-Meier survival analysis was performed using the survminer package in R software. The expression data of RNAs were subjected to univariate Cox regression analysis, which demonstrated that the mutation loads varied considerably among patients with AML. Subsequently, the expression data of mRNAs, microRNAs (miRNAs/miR) and long non-coding RNAs (lncRNAs) were subjected to univariate Cox regression analysis to determine the the 100 genes most associated with the survival of patients with AML, which revealed 48 mRNAs and 52 miRNAs. The top 1,900 mRNAs (P<0.05) were selected through enrichment analysis to determine their functional role in AML prognosis. The results demonstrated that these molecules were involved in the transforming growth factor-β, SMAD and fibroblast growth factor receptor-1 fusion mutant signaling pathways. Survival analysis indicated that patients with AML, with high MYH15, TREML2, ATP13A2, MMP7, hsa-let-7a-2-3p, hsa-miR-362-3p, hsa-miR-500a-5p, hsa-miR-500b-5p, hsa-miR-362-5p, LINC00987, LACAT143, THCAT393, THCAT531 and KHCAT230 expression levels had a shorter survival time compared with those without these factors. Conversely, a high KANSL1L expression level in patients was associated with a longer survival time. The present study determined genetic mutations, mRNAs, miRNAs, lncRNAs and signaling pathways involved in AML, in order to elucidate the underlying molecular mechanisms of the development and recurrence of this disease.

AMLVaran: a software approach to implement variant analysis of targeted NGS sequencing data in an oncological care setting

BACKGROUND

Next-Generation Sequencing (NGS) enables large-scale and cost-effective sequencing of genetic samples in order to detect genetic variants. After successful use in research-oriented projects, NGS is now entering clinical practice. Consequently, variant analysis is increasingly important to facilitate a better understanding of disease entities and prognoses. Furthermore, variant calling allows to adapt and optimize specific treatments of individual patients, and thus is an integral part of personalized medicine.However, the analysis of NGS data typically requires a number of complex bioinformatics processing steps. A flexible and reliable software that combines the variant analysis process with a simple, user-friendly interface is therefore highly desirable, but still lacking.

RESULTS

With AMLVaran (AML Variant Analyzer), we present a web-based software, that covers the complete variant analysis workflow of targeted NGS samples. The software provides a generic pipeline that allows free choice of variant calling tools and a flexible language (SSDL) for filtering variant lists. AMLVaran's interactive website presents comprehensive annotation data and includes curated information on relevant hotspot regions and driver mutations. A concise clinical report with rule-based diagnostic recommendations is generated.An AMLVaran configuration with eight variant calling tools and a complex scoring scheme, based on the somatic variant calling pipeline appreci8, was used to analyze three datasets from AML and MDS studies with 402 samples in total. Maximum sensitivity and positive predictive values were 1.0 and 0.96, respectively. The tool's usability was found to be satisfactory by medical professionals.

CONCLUSION

Coverage analysis, reproducible variant filtering and software usability are important for clinical assessment of variants. AMLVaran performs reliable NGS variant analyses and generates reports fulfilling the requirements of a clinical setting. Due to its generic design, the software can easily be adapted for use with different targeted panels for other tumor entities, or even for whole-exome data. AMLVaran has been deployed to a public web server and is distributed with Docker scripts for local use.

Nucleophosmin1 (NPM1) abnormality in hematologic malignancies, and therapeutic targeting of mutant NPM1 in acute myeloid leukemia

Nucleophosmin (NPM1) is an abundant nucleolar protein that is implicated in a variety of biological processes and in the pathogenesis of several human malignancies. For hematologic malignancies, approximately one-third of anaplastic large-cell non-Hodgkin’s lymphomas were found to express a fusion between NPM1 and the catalytic domain of anaplastic lymphoma receptor tyrosine kinase. About 50–60% of acute myeloid leukemia patients with normal karyotype carry NPM1 mutations, which are characterized by cytoplasmic dislocation of the NPM1 protein. Nevertheless, NPM1 is overexpressed in various hematologic and solid tumor malignancies. NPM1 overexpression is considered a prognostic marker of recurrence and progression of cancer. Thus, NPM1 abnormalities play a critical role in several types of hematologic malignancies. This has led to intense interest in the development of an NPM1 targeting strategy for cancer therapy. The aim of this review is to summarize present knowledge on NPM1 origin, pathogenesis, and therapeutic interventions in hematologic malignancies.

Advances in Genomic Profiling and Risk Stratification in Acute Myeloid Leukemia

OBJECTIVE

To review the current state of molecular and genetic profiling of acute myeloid leukemia (AML) and its implications.

DATA SOURCE

Peer-reviewed journal articles.

CONCLUSION

Significant advances in the understanding of the pathology of acute myeloid leukemia have led to refined risk stratification of patients and application of novel targeted therapies based on genetic profiles. Minimal residual disease testing allows for highly sensitive disease surveillance that can be used to predict relapse and assess treatment response.

IMPLICATIONS FOR NURSING PRACTICE

Accurate prognostication and therapeutic decision-making for patients with acute myeloid leukemia is dependent on molecular profiling. Being knowledgeable of the implications of minimal residual disease testing is critical for patient-centered care.

Ceramide Analogue SACLAC Modulates Sphingolipid Levels and MCL-1 Splicing to Induce Apoptosis in Acute Myeloid Leukemia

Acute myeloid leukemia (AML) is a disease characterized by uncontrolled proliferation of immature myeloid cells in the blood and bone marrow. The 5-year survival rate is approximately 25%, and recent therapeutic developments have yielded little survival benefit. Therefore, there is an urgent need to identify novel therapeutic targets. We previously demonstrated that acid ceramidase (ASAH1, referred to as AC) is upregulated in AML and high AC activity correlates with poor patient survival. Here, we characterized a novel AC inhibitor, SACLAC, that significantly reduced the viability of AML cells with an EC₅₀ of approximately 3 μmol/L across 30 human AML cell lines. Treatment of AML cell lines with SACLAC effectively blocked AC activity and induced a decrease in sphingosine 1-phosphate and a 2.5-fold increase in total ceramide levels. Mechanistically, we showed that SACLAC treatment led to reduced levels of splicing factor SF3B1 and alternative MCL-1 mRNA splicing in multiple human AML cell lines. This increased proapoptotic MCL-1S levels and contributed to SACLAC-induced apoptosis in AML cells. The apoptotic effects of SACLAC were attenuated by SF3B1 or MCL-1 overexpression and by selective knockdown of MCL-1S. Furthermore, AC knockdown and exogenous C16-ceramide supplementation induced similar changes in SF3B1 level and MCL-1S/L ratio. Finally, we demonstrated that SACLAC treatment leads to a 37% to 75% reduction in leukemic burden in two human AML xenograft mouse models. IMPLICATIONS: These data further emphasize AC as a therapeutic target in AML and define SACLAC as a potent inhibitor to be further optimized for future clinical development.

Multi-study reanalysis of 2,213 acute myeloid leukemia patients reveals age- and sex-dependent gene expression signatures

In 2019 it is estimated that more than 21,000 new acute myeloid leukemia (AML) patients will be diagnosed in the United States, and nearly 11,000 are expected to die from the disease. AML is primarily diagnosed among the elderly (median 68 years old at diagnosis). Prognoses have significantly improved for younger patients, but as much as 70% of patients over 60 years old will die within a year of diagnosis. In this study, we conducted a reanalysis of 2,213 acute myeloid leukemia patients compared to 548 healthy individuals, using curated publicly available microarray gene expression data. We carried out an analysis of normalized batch corrected data, using a linear model that included considerations for disease, age, sex, and tissue. We identified 974 differentially expressed probe sets and 4 significant pathways associated with AML. Additionally, we identified 375 age- and 70 sex-related probe set expression signatures relevant to AML. Finally, we trained a k nearest neighbors model to classify AML and healthy subjects with 90.9% accuracy. Our findings provide a new reanalysis of public datasets, that enabled the identification of new gene sets relevant to AML that can potentially be used in future experiments and possible stratified disease diagnostics.

Acute myeloid leukaemia

For several decades, few substantial therapeutic advances have been made for patients with acute myeloid leukaemia. However, since 2017 unprecedented growth has been seen in the number of drugs available for the treatment of acute myeloid leukaemia, with several new drugs receiving regulatory approval. In addition to advancing our therapeutic armamentarium, an increased understanding of the biology and genomic architecture of acute myeloid leukaemia has led to refined risk assessment of this disease, with consensus risk stratification guidelines now incorporating a growing number of recurrent molecular aberrations that aid in the selection of risk-adapted management strategies. Despite this promising recent progress, the outcomes of patients with acute myeloid leukaemia remain unsatisfactory, with more than half of patients ultimately dying from their disease. Enrolment of patients into clinical trials that evaluate novel drugs and rational combination therapies is imperative to continuing this progress and further improving the outcomes of patients with acute myeloid leukaemia.

[Clinical application of minimal residual disease detection in childhood acute leukemia]

In recent years, great progress has been made in the treatment outcome of childhood acute leukemia with the improvement of chemotherapy regimens and the introduction of risk-stratified therapy; however, minimal residual disease (MRD) is still a difficult problem which affects the prognosis of acute leukemia. MRD influences the selection of chemotherapy regimens and recurrence risk stratification, and meanwhile, it can be used for prognostic prediction. At present, flow cytometry and polymerase chain reaction are mainly used for MRD detection. The next-generation sequencing also plays an important role in MRD detection, especially in MRD detection after stem cell transplantation. This article reviews the methodology and significance of MRD detection in childhood acute leukemia.

Gene mutation patterns of Chinese acute myeloid leukemia patients by targeted next-generation sequencing and bioinformatic analysis

PURPOSES

The conventional risk stratification of acute myeloid leukemia (AML), based on cytogenetics, cannot meet the demand for accurate prognostic evaluations. In recent years, gene mutations are found to be potential markers for more accurate risk stratification, but reports on mutation screening of Chinese AML are limited. We aim to display the mutation patterns of Chinese AML patients, reveal the genotype-phenotype correlations and make a comparison with Caucasians patients.

METHODS

Genome DNA from 78 patients' bone marrow were extracted for targeted gene mutation panel by next-generation sequencing (NGS) technology. Statistics and bioinformatics were used to analyze the correlations between gene mutations and clinical features, as well as the comparison of our results with the Cancer Genome Atlas Research Network (TCGA) public AML dataset.

RESULTS

We found patients with mutations of FLT3 and TET2 had higher bone marrow blasts, peripheral blasts and white blood cell (WBC) count, mutations of SRSF2 were related with age, and mutations of FLT3-ITD, DNMT3A, IDH1, TET2 and SRSF2 were risk factors for overall survival. What's more, we discovered 15 novel mutations and difference of mutational incidence in 6 genes between Chinese and Caucasians AML. Bioinformatic analysis revealed some relationship between gene mutations and expressions as well as drug sensitivities.

CONCLUSIONS

We made an investigation on the mutation patterns of Chinese AML patients by NGS technique and revealed correlations between gene mutations and clinical features. Thus we recommend routine testing of suspected genes for better prognostic prediction and individualized treatment.

Gene Mutations as Emerging Biomarkers and Therapeutic Targets for Relapsed Acute Myeloid Leukemia

It is believed that there are key differences in the genomic profile between adult and childhood acute myeloid leukemia (AML). Relapse is the significant contributor of mortality in patients with AML and remains as the leading cause of cancer death among children, posing great challenges in the treatment of AML. The knowledge about the genomic lesions in childhood AML is still premature as most genomic events defined in children were derived from adult cohorts. However, the emerging technologies of next generation sequencing have narrowed the gap of knowledge in the biology of AML by the detection of gene mutations for each sub-type which have led to the improvement in terms of prognostication as well as the use of targeted therapies. In this review, we describe the recent understanding of the genomic landscape including the prevalence of mutation, prognostic impact, and targeted therapies that will provide an insight into the pathogenesis of AML relapse in both adult and childhood cases.

Inhibition of SDF-1-induced migration of oncogene-driven myeloid leukemia by the L-RNA aptamer (Spiegelmer), NOX-A12, and potentiation of tyrosine kinase inhibition

Resistance to targeted tyrosine kinase inhibitors (TKI) remains a challenge for the treatment of myeloid leukemias. Following treatment with TKIs, the bone marrow microenvironment has been found to harbor a small pool of surviving leukemic CD34+ progenitor cells. The long-term survival of these leukemic cells has been attributed, at least in part, to the protective effects of bone marrow stroma. We found that the NOX-A12 'Spiegelmer', an L-enantiomeric RNA oligonucleotide that inhibits SDF-1α, showed in vitro and in vivo activity against BCR-ABL- and FLT3-ITD-dependent leukemia cells. NOX-A12 was sufficient to suppress SDF-1-induced migration in vitro. The combination of NOX-A12 with TKIs reduced cell migration in the same in vitro model of SDF-1-induced chemotaxis to a greater extent than either drug alone, suggesting positive cooperativity as a result of the SDF-1 blocking function of NOX-A12 and cytotoxicity resulting from targeted oncogenic kinase inhibition. These results are consistent with our in vivo findings using a functional pre-clinical mouse model of chronic myeloid leukemia (CML), whereby we demonstrated the ability of NOX-A12, combined with the ABL kinase inhibitor, nilotinib, to reduce the leukemia burden in mice to a greater extent than either agent alone. Overall, the data support the idea of using SDF-1 inhibition in combination with targeted kinase inhibition to override drug resistance in oncogene-driven leukemia to significantly diminish or eradicate residual leukemic disease.

Inhibition of USP10 induces degradation of oncogenic FLT3

Oncogenic forms of the kinase FLT3 are important therapeutic targets in acute myeloid leukemia (AML); however, clinical responses to small-molecule kinase inhibitors are short-lived as a result of the rapid emergence of resistance due to point mutations or compensatory increases in FLT3 expression. We sought to develop a complementary pharmacological approach whereby proteasome-mediated FLT3 degradation could be promoted by inhibitors of the deubiquitinating enzymes (DUBs) responsible for cleaving ubiquitin from FLT3. Because the relevant DUBs for FLT3 are not known, we assembled a focused library of most reported small-molecule DUB inhibitors and carried out a cellular phenotypic screen to identify compounds that could induce the degradation of oncogenic FLT3. Subsequent target deconvolution efforts allowed us to identify USP10 as the critical DUB required to stabilize FLT3. Targeting of USP10 showed efficacy in preclinical models of mutant-FLT3 AML, including cell lines, primary patient specimens and mouse models of oncogenic-FLT3-driven leukemia.

Characterization of midostaurin as a dual inhibitor of FLT3 and SYK and potentiation of FLT3 inhibition against FLT3-ITD-driven leukemia harboring activated SYK kinase

Oncogenic FLT3 kinase is a clinically validated target in acute myeloid leukemia (AML), and both multi-targeted and selective FLT3 inhibitors have been developed. Spleen tyrosine kinase (SYK) has been shown to be activated and increased in FLT3-ITD-positive AML patients, and has further been shown to be critical for transformation and maintenance of the leukemic clone in these patients. Further, over-expression of constitutively activated SYK causes resistance to highly selective FLT3 tyrosine kinase inhibitors (TKI). Up to now, the activity of the multi-targeted FLT3 inhibitor, midostaurin, against cells expressing activated SYK has not been explored in the context of leukemia, although SYK has been identified as a target of midostaurin in systemic mastocytosis. We compared the ability of midostaurin to inhibit activated SYK in mutant FLT3-positive AML cells with that of inhibitors displaying dual SYK/FLT3 inhibition, targeted SYK inhibition, and targeted FLT3 inhibition. Our findings suggest that dual FLT3/SYK inhibitors and FLT3-targeted drugs potently kill oncogenic FLT3-transformed cells, while SYK-targeted small molecule inhibition displays minimal activity. However, midostaurin and other dual FLT3/SYK inhibitors display superior anti-proliferative activity when compared to targeted FLT3 inhibitors, such as crenolanib and quizartinib, against cells co-expressing FLT3-ITD and constitutively activated SYK-TEL. Interestingly, additional SYK suppression potentiated the effects of dual FLT3/SYK inhibitors and targeted FLT3 inhibitors against FLT3-ITD-driven leukemia, both in the absence and presence of activated SYK. Taken together, our findings have important implications for the design of drug combination studies in mutant FLT3-positive patients and for the design of future generations of FLT3 inhibitors.

NPM1 Mutant Mediated PML Delocalization and Stabilization Enhances Autophagy and Cell Survival in Leukemic Cells

Accumulating evidence has defined nucleophosmin 1 (NPM1) mutation as a driver genetic event in acute myeloid leukemia (AML), whereas the pathogenesis of NPM1-mutated AML remains to be fully elucidated. In this study, we showed that mutant NPM1 elevated autophagic activity and autophagic activation contributed to leukemic cell survival in vitro. Meanwhile, we also found high expression of promyelocytic leukemia gene (PML) and its cytoplasmic dislocation in primary NPM1-mutated AML blasts and NPM1-mA positive OCI-AML3 cells. Mechanically, mutant NPM1 interacted with PML and mediated it delocalization as well as stabilization. Notably, NPM1-mA knockdown impaired autophagic activity, while induced expression of PML reversed this effect. Finally, we confirmed that PML modulated autophagic activity via AKT signal. These findings suggest that aberrant PML expression and autophagy are beneficial to the leukemic transformation driven by NPM1 mutations. This indicates an attractive therapeutic avenue for PML targeting and/or autophagy inhibition in the treatment of NPM1-mutated AML.

Anti-proliferative activity of the NPM1 interacting natural product avrainvillamide in acute myeloid leukemia

Mutated nucleophosmin 1 (NPM1) acts as a proto-oncogene and is present in ~30% of patients with acute myeloid leukemia (AML). Here we examined the in vitro and in vivo anti-leukemic activity of the NPM1 and chromosome region maintenance 1 homolog (CRM1) interacting natural product avrainvillamide (AVA) and a fully syntetic AVA analog. The NPM1-mutated cell line OCI-AML3 and normal karyotype primary AML cells with NPM1 mutations were significantly more sensitive towards AVA than cells expressing wild-type (wt) NPM1. Furthermore, the presence of wt p53 sensitized cells toward AVA. Cells exhibiting fms-like tyrosine kinase 3 (FLT3) internal tandem duplication mutations also displayed a trend toward increased sensitivity to AVA. AVA treatment induced nuclear retention of the NPM1 mutant protein (NPMc+) in OCI-AML3 cells and primary AML cells, caused proteasomal degradation of NPMc+ and the nuclear export factor CRM1 and downregulated wt FLT3 protein. In addition, both AVA and its analog induced differentiation of OCI-AML3 cells together with an increased phagocytotic activity and oxidative burst potential. Finally, the AVA analog displayed anti-proliferative activity against subcutaneous xenografted HCT-116 and OCI-AML3 cells in mice. Our results demonstrate that AVA displays enhanced potency against defined subsets of AML cells, suggesting that therapeutic intervention employing AVA or related compounds may be feasible.

Acute Myeloid Leukemia Targeting by Chimeric Antigen Receptor T Cells: Bridging the Gap from Preclinical Modeling to Human Studies

Acute myeloid leukemia (AML) still represents an unmet clinical need for adult and pediatric high-risk patients, thus demanding advanced and personalized therapies. In this regard, different targeted immunotherapeutic approaches are available, ranging from naked monoclonal antibodies (mAb) to conjugated and multifunctional mAbs (i.e., BiTEs and DARTs). Recently, researchers have focused their attention on novel techniques of genetic manipulation specifically to redirect cytotoxic T cells endowed with chimeric antigen receptors (CARs) toward selected tumor associated antigens. So far, CAR T cells targeting the CD19 antigen expressed by B-cell origin hematological cancers have gained impressive clinical results, leading to the possibility of translating the CAR platform to treat other hematological malignancies such as AML. However, one of the main concerns in the field of AML CAR immunotherapy is the identification of an ideal target cell surface antigen, being highly expressed on tumor cells but minimally present on healthy tissues, together with the design of an anti-AML CAR appropriately balancing efficacy and safety profiles. The current review focuses mainly on AML target antigens and the related immunotherapeutic approaches developed so far, deeply dissecting methods of CAR T cell safety improvements, when designing novel CARs approaching human studies.

High expression of S100A8 gene is associated with drug resistance to etoposide and poor prognosis in acute myeloid leukemia through influencing the apoptosis pathway

S100A8 has been increasingly recognized as a biomarker in multiple solid tumors and has played pivotal roles in hematological malignancies. S100A8 is potentially an indicator for poor survival in acute myeloid leukemia (AML) in retrospective studies. However, the mechanisms of S100A8 are diverse in cancers. In this study, we investigated the correlation of S100A8 at the transcription level with clinical parameters in 91 de novo AML patients and explored its mechanisms of chemoresistance to etoposide in vitro. The transcription level of S100A8 was significantly lower at initial and relapse stages of AML samples than at complete remission (P<0.001) and than in the control group (P=0.0078), while no significant difference could be found between initial and relapse stages (P=0.257). Patients with high transcription levels of S100A8 exhibited a shorter overall survival (P=0.0012). HL-60 cells transfected with S100A8 showed resistance to etoposide with a higher level IC50 value and lower apoptosis rate compared with HL-60 cells transfected with empty vector. Thirty-six genes were significantly downregulated and 12 genes were significantly upregulated in S100A8 overexpression group compared with control group in which 360 genes involved in apoptotic genes array were performed by real-time reverse transcriptase polymerase chain reaction. Among them, the caspase-3, Bcl-2, and Bax were verified by Western blot analysis which indicated that the role of S100A8 in resistance to chemotherapy was closely related with antiapoptosis. In conclusion, critical S100A8 provided useful clinical information in predicting the outcome of AML. The main mechanism of S100A8 which promoted chemoresistance was antiapoptosis.

NPM1, FLT3 and CEBPA mutations in pediatric patients with AML from Argentina: incidence and prognostic value

Mutations in NPM1, FLT3 and CEBPA genes are found in 25-35 % of adult acute myeloblastic leukemia (AML) cases and correlate with prognosis. To date, there have been no reports about these mutations in pediatric AML from Argentina. The aims of the present study were to describe the incidence of NPM1, FLT3 and CEBPA mutations and to analyze their prognostic impact in this population. The incidences of these mutations within a population of 216 pediatric AML cases were: NPM1-mutated 4.2 %, CEBPA-mutated 1.9 %, FLT3-ITD 10.2 % and FLT3-TKD 7.9 %. Among 33 patients with normal karyotype, we found significantly higher frequencies for NPM1-mutated 24.2 % and CEBPA-mutated 12.1 %. Overall survival (pOS) for the 163 eligible non-acute promyelocytic leukemia cases was 46.2 ± 4.3 %, while leukemia-free survival probability was 51.0 ± 4.4 % (n = 135). The NPM1-mutated/FLT3-ITD-negative genotype showed better outcome than any other combined NPM1/FLT3 genotype; this difference was statistically significant within the group of high-risk patients (pOS ± SE 83.3 ± 15.2 % versus 33.1 ± 4.7 %; p = 0.0251). This is the first report of the frequencies of these mutations in Argentina. Despite the limited number of patients, a favorable prognosis of AML with genotype NPM1-mutated/FLT3-ITD-negative was confirmed. This is especially relevant within the high-risk group of patients, as it may contribute to the detection of patients with better prognosis, and thus avoid unnecessary treatment intensification.

Computational Approach to Annotating Variants of Unknown Significance in Clinical Next Generation Sequencing

Next generation sequencing (NGS) has become a common technology in the clinical laboratory, particularly for the analysis of malignant neoplasms. However, most mutations identified by NGS are variants of unknown clinical significance (VOUS). Although the approach to define these variants differs by institution, software algorithms that predict variant effect on protein function may be used. However, these algorithms commonly generate conflicting results, potentially adding uncertainty to interpretation. In this review, we examine several computational tools used to predict whether a variant has clinical significance. In addition to describing the role of these tools in clinical diagnostics, we assess their efficacy in analyzing known pathogenic and benign variants in hematologic malignancies.

A Crowdsourcing Approach to Developing and Assessing Prediction Algorithms for AML Prognosis

Acute Myeloid Leukemia (AML) is a fatal hematological cancer. The genetic abnormalities underlying AML are extremely heterogeneous among patients, making prognosis and treatment selection very difficult. While clinical proteomics data has the potential to improve prognosis accuracy, thus far, the quantitative means to do so have yet to be developed. Here we report the results and insights gained from the DREAM 9 Acute Myeloid Prediction Outcome Prediction Challenge (AML-OPC), a crowdsourcing effort designed to promote the development of quantitative methods for AML prognosis prediction. We identify the most accurate and robust models in predicting patient response to therapy, remission duration, and overall survival. We further investigate patient response to therapy, a clinically actionable prediction, and find that patients that are classified as resistant to therapy are harder to predict than responsive patients across the 31 models submitted to the challenge. The top two performing models, which held a high sensitivity to these patients, substantially utilized the proteomics data to make predictions. Using these models, we also identify which signaling proteins were useful in predicting patient therapeutic response.