Genes In Acute Myeloid Leukemia Research Articles

Erythroid Predominance in Bone Marrow Biopsies of Acute Myeloid Leukemia Patients after Decitabine Treatment Correlates with Mutation Profile and Complete Remission.

Acute myeloid leukemia (AML) patients may receive hypomethylating agents such as decitabine (DAC) as part of their treatment. Not all patients respond to this therapy, and if they do, the clinical response may occur only after 3-6 courses of treatment. Hence, early biomarkers predicting response would be very useful. We retrospectively analyzed a cohort of 22 AML patients who were treated with DAC. Histology of the bone marrow biopsy, pathogenic mutations, and methylation status were related to the treatment response. In 8/22 (36%) patients, an erythroid dominant response (EDR) pattern, defined as a ratio of myeloid cells/erythroid cells <1, was observed. In the remaining 14 cases, a myeloid predominance was preserved during treatment. No difference in the hypomethylating effect of DAC treatment was observed in patients with and without EDR, as global 5-methylcytosine levels dropped similarly in both groups. Mutational analysis by NGS using a panel of commonly mutated genes in AML showed that patients with an early EDR harbored on average less mutations, with U2AF1 mutations occurring more frequently, whereas RUNX1 mutations were underrepresented compared to non-EDR cases. Interestingly, the development of an EDR correlated with complete remission (7/8 cases with an EDR vs. only 2/14 cases without an EDR). We conclude that early histological bone marrow examination for the development of an EDR may be helpful to predict response in AML patients during treatment with DAC.

NET-related gene signature for predicting AML prognosis

Acute Myeloid Leukemia (AML) is a malignant blood cancer with a high mortality rate. Neutrophil extracellular traps (NETs) influence various tumor outcomes. However, NET-related genes (NRGs) in AML had not yet received much attention. This study focuses on the role of NRGs in AML and their interaction with the immunological microenvironment. The gene expression and clinical data of patients with AML were downloaded from the TCGA-LAML and GEO cohorts. We identified 148 NRGs through the published article. Univariate Cox regression was used to analyze the association of NRGs with overall survival (OS). The least absolute shrinkage and selection operator were utilized to assess the predictive efficacy of NRGs. Kaplan–Meier plots visualized survival estimates. ROC curves assessed the prognostic value of NRG-based features. A nomogram, integrating clinical information and prognostic scores of patients, was constructed using multivariate logistic regression and Cox proportional hazards regression models. Twenty-seven NRGs were found to significantly impact patient OS. Six NRGs—CFTR, ENO1, PARVB, DDIT4, MPO, LDLR—were notable for their strong predictive ability regarding patient survival. The ROC values for 1-, 3-, and 5-year survival rates were 0.794, 0.781, and 0.911, respectively. In the training set (TCGA-LAML), patients in the high NRG risk group showed a poorer prognosis (p < 0.001), which was validated in two external datasets (GSE71014 and GSE106291). The 6-NRG signature and corresponding nomograms exhibit superior predictive accuracy, offering insights for pre-immune response evaluation and guiding future immuno-oncology treatments and drug selection for AML patients.

Identification of hub genes and potential molecular mechanisms related to drug sensitivity in acute myeloid leukemia based on machine learning.

Background: Acute myeloid leukemia (AML) is the most common form of leukemia among adults and is characterized by uncontrolled proliferation and clonal expansion of hematopoietic cells. There has been a significant improvement in the treatment of younger patients, however, prognosis in the elderly AML patients remains poor. Methods: We used computational methods and machine learning (ML) techniques to identify and explore the differential high-risk genes (DHRGs) in AML. The DHRGs were explored through multiple in silico approaches including genomic and functional analysis, survival analysis, immune infiltration, miRNA co-expression and stemness features analyses to reveal their prognostic importance in AML. Furthermore, using different ML algorithms, prognostic models were constructed and validated using the DHRGs. At the end molecular docking studies were performed to identify potential drug candidates targeting the selected DHRGs. Results: We identified a total of 80 DHRGs by comparing the differentially expressed genes derived between AML patients and normal controls and high-risk AML genes identified by Cox regression. Genetic and epigenetic alteration analyses of the DHRGs revealed a significant association of their copy number variations and methylation status with overall survival (OS) of AML patients. Out of the 137 models constructed using different ML algorithms, the combination of Ridge and plsRcox maintained the highest mean C-index and was used to build the final model. When AML patients were classified into low- and high-risk groups based on DHRGs, the low-risk group had significantly longer OS in the AML training and validation cohorts. Furthermore, immune infiltration, miRNA coexpression, stemness feature and hallmark pathway analyses revealed significant differences in the prognosis of the low- and high-risk AML groups. Drug sensitivity and molecular docking studies revealed top 5 drugs, including carboplatin and austocystin-D that may significantly affect the DHRGs in AML. Conclusion: The findings from the current study identified a set of high-risk genes that may be used as prognostic and therapeutic markers for AML patients. In addition, significant use of the ML algorithms in constructing and validating the prognostic models in AML was demonstrated. Although our study used extensive bioinformatics and machine learning methods to identify the hub genes in AML, their experimental validations using knock-out/-in methods would strengthen our findings.

Research Progress of Isocitrate Dehydrogenase Mutation-Positive Acute Myeloid Leukemia --Review

Isocitrate dehydrogenase (IDH) is an enzymes involved in a variety of metabolic and epigenetic processes. IDH can be detected in approximately 20% of patients with acute myeloid leukemia (AML), the mutated IDH enzyme acquires new oncogenic enzyme activity and converts α-ketoglutaric acid (α-KG) to the tumor metabolite 2-hydroxyglutaric acid (2-HG), which accumulates at high levels in cells and hinders the function of αKG-dependent enzymes, including epigenetic regulators, resulting in DNA hypermethylation, abnormal gene expression, cell proliferation, and abnormal differentiation, and contributes to leukemia disease progression. IDH mutations have different effects on the prognosis of patients with AML depending on the location of the mutation and other co-occurring genomic abnormalities. This paper will review the latest research progress on the IDH positive AML gene changes, prognosis, and inhibitors.

Abstract 1687: Targeted degradation of MECOM in high-risk acute myeloid leukemia reveals a novel repressive function that is amenable to therapeutic small-molecule rewiring

Abstract Hematopoiesis relies on an intricate balance between stem-cell self-renewal and terminal maturation of blood cells. Disrupting this balance can lead to the development of deadly blood cancers, like acute myeloid leukemia (AML). Increasing evidence suggests that acquiring hematopoietic stem cell (HSC) gene expression programs in AML confers a particularly poor prognosis and increases risk of relapse with conventional therapy. Acquisition of these features in AML is commonly driven by dysregulation of MECOM, a transcription factor and master regulator of HSC self-renewal. To define the role of MECOM in AMLs, we engineered cell-line models of high-risk AML by endogenously tagging MECOM with an FKBP12F36V degron. These models enable targeted degradation of MECOM which we employed in concert with multi-omic readouts to assess changes in nascent transcription and chromatin accessibility to identify direct transcriptional targets of MECOM. We demonstrate that MECOM degradation results in a rapid increase in chromatin accessibility at MECOM-bound sites and increased expression of cognate genes to establish a pro-differentiation gene program. These findings suggest a previously unappreciated mechanism for MECOM in repressing differentiation-promoting cis-regulatory elements (cisREs) and their cognate target genes in AML. We then employed a pooled CRISPR inhibition (CRISPRi) screen to functionally characterize the role that each cisRE plays in promoting high-risk features in AML. Utilizing CRISPRi to repress MECOM-bound cisREs in concert with dTAG-mediated MECOM degradation, we examined if repression of over 500 individual MECOM-bound cisREs is sufficient to maintain AML progenitors in the absence of MECOM. This functional dissection revealed that the individual repression of three cisREs that regulate CEBPA, GFI1B, and RUNX1 is sufficient to maintain AML progenitor cells in the absence of MECOM. This result implicates MECOM as a direct repressor of known regulators of myeloid differentiation. Given these findings, we hypothesized that small molecule-based recruitment of a transcriptional coactivator to MECOM could rewire its repressive function to activate myeloid differentiation and subsequent leukemia cell death. To test this approach, we treated a MECOM-FKBP12F36V AML degron model with the bifunctional small molecule NICE-01 (AP1867-PEG2-JQ1) to recruit an epigenetic activator (BRD4) to MECOM to functionally rewire this transcriptional network. NICE-01 treatment induced significant differentiation of AML progenitor cells relative to JQ1 treatment alone. Our work highlights the utility of targeted protein degradation to mechanistically interrogate the function of a key driver of high-risk AMLs and suggests the potential for small molecule-rewiring of stem cell gene regulatory networks to confer therapeutic benefit. Citation Format: Travis J. Fleming, Michael Gundry, Richard Voit, Mateusz Antoszewski, William J. Gibson, Ananthan Sadagopan, Vijay G. Sankaran. Targeted degradation of MECOM in high-risk acute myeloid leukemia reveals a novel repressive function that is amenable to therapeutic small-molecule rewiring [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 1687.

Potential Correlation between Gene Mutations and Metabolic Changes in Acute Myeloid Leukemia

Abstract: Acute myeloid leukemia (AML) is a common type of leukemia. However, the understanding of AML remains insufficient. The pathological progression of AML is closely related to chromosome abnormalities and genetic mutations. Gene mutation is an important factor in the pathogenesis of AML and a potential cause of drug resistance. Recent studies have shown that gene mutations in AML can cause metabolic changes. Metabolites, as downstream products of human physiological activities, can amplify physiological and disease-related signals. Therefore, the analysis of metabolite markers related to gene mutations can be used for early prediction of the occurrence of the disease. This review describes the types and significance of AML gene mutations and analyzes the characteristics of metabolic changes related to gene mutations.

A combined immune and exosome-related risk signature as prognostic biomakers in acute myeloid leukemia

ABSTRACT Objectives Acute myeloid leukemia (AML) is one of the common hematological diseases with low survival rates. Studies have highlighted the dysregulated expression of immune-related and exosome-related genes (ERGs) in cancers. Nevertheless, it remains to be determined whether combining these genes have a prognostic significance in AML. Methods Immune-ERG profiles for 151 AML patients from TCGA were analyzed. A risk model was constructed and optimized through the combination of univariate Cox regression and LASSO regression analysis. GEO datasets were utilized as the external validation for the robustness of the risk model. In addition, we performed KEGG and GO enrichment analyses to investigate the role played by these genes in AML. The variations in immune cell infiltrations among risk groups were assessed through four algorithms. Expression of hub gene in specific cell was analyzed by single-cell RNA seq. Results A total of 85 immune-ERGs associated with prognosis were identified, enabling the construction of a risk model for AML. The risk model based on five immune-ERGs (CD37, NUCB2, LSP1, MGST1, and PLXNB1) demonstrated a correlation with the clinical outcomes. Additionally, age, FAB classification, cytogenetics risk, and risk score were identified as independent prognostic factors. The five immune-ERGs exhibited correlations with cytokine-cytokine receptor interaction, and antigen processing and presentation. Notably, the risk model demonstrated significant associations with immune responses and the expression of immune checkpoints. Conclusions An immune-ERG-based risk model was developed to effectively predict prognostic outcomes for AML patients. There is potential for immune therapy in AML targeting the five hub genes.

Suppression of DNMT1 combined with ATM or ATR inhibitor as a therapeutic combination of acute myeloid leukemia.

The potential treatment option of targeting DNA methyltransferase 1 (DNMT1) has been explored, but further investigation is required to assess the efficacy of combination therapy in acute myeloid leukemia (AML). In this study, bioinformatics and online databases were utilized to select the combined therapeutic targets. The potential kinases associated with DNMT1-related genes in AML were analyzed using the Cancer Genome Atlas (TCGA) database and X2K Appyter (Expression2Kinases) database. In-vitro evaluations were conducted to assess the synergistic effects between DNMT1 and ATR/ATM in five AML cell lines (MOLM-16, NB-4, HEL 92.1.7, HEL, EOL-1). In our study, ATR and ATM are primarily the kinases associated with DNMT1-related genes in AML. We observed a significant upregulation of DNMT1, ATR, and ATM expression in AML tissues and cell lines. The five AML cell lines demonstrated sensitivity to monotherapy with GSK-368, AZD-1390, or AZD-6738 (EC50 value ranges from 5.461 to 7.349 nM, 5.821 to 10.120 nM, and 7.618 to 10.100 nM, respectively). A considerable synergistic effect was observed in AML cell lines when combining GSK-368 and AZD-1390, GSK-368 and AZD-6738, or AZD-1390 and AZD-6738, resulting in induced cell apoptosis and inhibited cell growth. DNMT1, ATM, and ATR possess potential as therapeutic targets for AML. Both individual targeting and combination targeting of these molecules have been confirmed as promising therapeutic approaches for AML.

Reduced Proteolipid Protein 2 promotes endoplasmic reticulum stress-related apoptosis and increases drug sensitivity in acute myeloid leukemia.

The Proteolipid Protein 2 (PLP2), a protein in the Endoplasmic Reticulum (ER) membrane, has been reported to be highly expressed in various tumors. Previous studies have demonstrated that the reduced PLP2 can induce apoptosis and autophagy through ER stress-related pathways, leading to a decreased proliferation and aggressiveness. However, there is no research literature on the role of PLP2 in Acute Myeloid Leukemia (AML). PLP2 expression, clinical data, genetic mutations, and karyotype changes from GEO, TCGA, and timer2.0 databases were analyzed through the R packages. The possible functions and pathways of cells were explored through GO, KEGG, and GSEA enrichment analysis using the clusterProfiler R package. Immuno-infiltration analysis was conducted using the Cibersort algorithm and the Xcell R package. RT-PCR and western blot techniques were employed to identify the PLP2 expression, examine the knockdown effects in THP-1 cells, and assess the expression of genes associated with endoplasmic reticulum stress and apoptosis. Flow cytometry was utilized to determine the apoptosis and survival rates of different groups. PLP2 expression was observed in different subsets of AML and other cancers. Enrichment analyses revealed that PLP2 was involved in various tumor-related biological processes, primarily apoptosis and lysosomal functions. Additionally, PLP2 expression showed a strong association with immune cell infiltration, particularly monocytes. In vitro, the knockdown of PLP2 enhanced endoplasmic reticulum stress-related apoptosis and increased drug sensitivity in THP-1 cells. PLP2 could be a novel therapeutic target in AML, in addition, PLP2 is a potential endoplasmic reticulum stress regulatory gene in AML.

Panel-based RNA fusion sequencing improves diagnostics of pediatric acute myeloid leukemia

New methods like panel-based RNA fusion sequencing (RNA-FS) promise improved diagnostics in various malignancies. We here analyzed the impact of RNA-FS on the initial diagnostics of 241 cases with pediatric acute myeloid leukemia (AML). We show that, compared to classical cytogenetics (CCG), RNA-FS reliably detected risk-relevant fusion genes in pediatric AML. In addition, RNA-FS strongly improved the detection of cryptic fusion genes like NUP98::NSD1, KMT2A::MLLT10 and CBFA2T3::GLIS2 and thereby resulted in an improved risk stratification in 25 patients (10.4%). Validation of additionally detected non-risk-relevant high confidence fusion calls identified PIM3::BRD1, C22orf34::BRD1, PSPC1::ZMYM2 and ARHGAP26::NR3C1 as common genetic variants and MYB::GATA1 as recurrent aberration, which we here describe in AML subtypes M0 and M7 for the first time. However, it failed to detect rare cytogenetically confirmed fusion events like MNX1::ETV6 and other chromosome 12p-abnormalities. As add-on benefit, the proportion of patients for whom measurable residual disease (MRD) monitoring became possible was increased by RNA-FS from 44.4 to 75.5% as the information on the fusion transcripts’ sequence allowed the design of new MRD assays.

Evaluation of Neddylation and Apoptosis-Related Gene Expression in Patients with Acute Myeloid Leukemia

Introduction Regulated cell death (RCD) is a process commonly dysregulated in patients (pts) with acute myeloid leukemia (AML), resulting in the survival of genetically unstable cells. Apoptosis, as the best-known form of RCD, interacts with neddylation, a process that contributes to tumorigenesis and apoptosis resistance. Aims This study was conducted to determine the expression of the selected genes involved in the neddylation pathway and to assess their clinical importance along with selected interacting proapoptotic genes. In addition, we correlated the expression levels of these genes with known prognostic factors in AML and determined their impact on the survival of AML pts. Methods The expression of selected proapoptotic genes BIK, BAX, BAK, BCL2L11, BBC3 , PMAIP1 CASP3, CASP7, and neddylation-related genes: CUL1, CUL2 , CUL4A, CUL5, CUL7, CUL9, NEDD8 was determined in duplicates in bone marrow samples of newly diagnosed AML pts. Real-Time PCR was carried out using the TaqMan chemistry and the QuantStudio7 thermal cycler (Applied Biosystems-Thermo Fisher Scientific). Gene expression was normalized using reference genes selected by the Normirazor tool. The normalization was performed by ∆Ct = Ct (reference) - Ct (mRNA of interest). This approach results in higher values for higher mRNA expression. Differential expression analysis was performed using a Welch t-test. Kaplan-Meier method with the log-rank test was used to assess overall survival (OS). Results In a prospective study, we included 40 newly diagnosed AML pts (mean age 62; range 26-87) with a median (m) follow-up of 6.7 months (95% CI: 4.5-9.1). High-risk AML was present in 52.5%, intermediate-risk in 32.5%, and low-risk in 15% of pts, according to European LeukemiaNet (ELN) 2022 risk stratification. NPM1 mutation was present in 23%, whereas FLT3 ITD or TKD mutation in 25% of pts. Intensive treatment was introduced in 43% of pts, while 25% were treated with azacitidine+venetoclax. Non-intensive treatment with azacitidine in monotherapy was administered to the remaining pts. BAK expression was detected in 70%, BIK in 98%, while expression of the other genes was found in all pts. In the high-risk group, we detected lower expression of both proapoptotic BAX (fold change - FC=0.7, p=0.01) and BIK gene (FC=0.4, p=0.01), as well as lower expression of CUL9 (FC=0.7, p=0.03). Accordingly, in pts with NPM1 mutation we revealed upregulation of BIK (FC=6.1, p=0.001), and CUL9 (FC=1.6, p=0.01). Whereas pts with FLT3 mutation had lower expression of proapoptotic BBC3 (FC=0.5, p=0.01), and neddylation-related CUL1 (FC=0.6, p=0.01). In cases of initial bone marrow blasts infiltration above median value (&amp;gt;49%) BCL2L11 CUL5 , NEDD8 and PMAIP1were downregulated ( p=0.001-0.02), while CUL7 ( p=0.00) and CASP3 ( p=0.04) were upregulated. Patients with initial white blood cell count &amp;gt;20 G/l had lower expression of BCL2L11 ( p=0.005), and CUL4A ( p=0.02), while higher expression of CASP7 ( p=0.04). The mOS in the study cohort was not reached. OS was longer in pts with higher (&amp;gt; -2.061, cutoff was determined with CutOff Finder) BAX expression (log-rank: p=0.03) [Figure 1]. The mOS was not reached in this group, whereas the mOS in pts with lower BAX expression was 1.3 months (95% CI: 0.6-1.3). In univariate Cox regression analysis, higher BAX expression (HR 0.31, 95%CI: 0.11-0.84, p=0.022), higher albumin level (HR 0.13, 95%CI: 0.04-0.41, p=0.0004), and intensive treatment (HR 0.18, 95%CI: 0.04-0.69, p=0.012) were factors influencing the outcome. In the multivariate model for OS, higher expression of BAX (HR 0.03, 95%CI: 0.003-0.33, p=0.004) retained its significant protective effect in the context of established prognostic factors [Table 1]. Conclusions To our knowledge, we were the first to evaluate such a complex spectrum of neddylation and apoptosis-related genes in AML. We revealed dysregulation of these genes in AML. Our data indicate that upregulation of BAX at the diagnosis is associated with longer OS. Moreover, we reported significantly lower BAX expression in ELN high-risk group. Thus, indicating BAX may be a potential prognostic factor in AML. Our preliminary results did not prove significant differences in the effect of neddylation gene expression levels on the prognosis of AML patients. As studies are emerging on the potential of neddylation-targeted therapies, we are conducting further research to verify the effect of neddylation on AML.

NAMPT Haploinsufficiency Is a Therapeutic Vulnerability in High-Risk Myeloid Malignancies

Monosomy 7 (−7) and del7q are the most common high-risk cytogenetic abnormalities and occur across the spectrum of myeloid disorders. -7/del(7q) also co-occur with other high-risk factors such as mutations or deletion of TP53. Standard, non-specific chemotherapy drugs are less effective in these high-risk patients, resulting in a median survival rate of approximately one year. To identify novel, targeted agents for these neoplasms, we sought “collateral lethal” genes, i.e. essential, druggable genes encoded on chromosome 7 that are haploinsufficient upon their loss of heterozygosity. To this end, we first identified essential genes located on chromosome 7. We mined genome-wide CRISPR/Cas9 screen data from 27 human acute myeloid leukemia (AML) cell lines within the DepMap database and identified 65 chromosome 7-encoded, candidate essential genes in AML. To determine those essential genes with known inhibitors, we intersected these 65 candidates with the Drug-Gene Interaction and canSAR.ai databases. We found that nicotinamide phosphoribosyltransferase ( NAMPT), the rate-limiting enzyme that catalyzes the first step of NAD + biosynthesis from nicotinamide, was one of four essential and druggable targets on chromosome 7. Notably, NAMPT was the only essential gene on chromosome 7 with a first-in-class orally bioavailable inhibitor, KPT 9274, currently in clinical trials (NCT04914845). Moreover, NAMPT DNA copy number, mRNA, and protein levels all negatively correlated with cell line sensitivity to NAMPT loss, implicating NAMPT as a collateral lethal candidate gene. We confirmed that isogenic human AML cell lines CRISPR-engineered to partially reduce NAMPT DNA copy led to reduced NAMPT protein levels, indicating NAMPT is a haploinsufficient gene. Cells with ~50% NAMPT levels were significantly more sensitive to the KPT 9274 treatment, and became less viable and more apoptotic, compared to control locus edited cells. To determine whether TP53 status could alter this vulnerability, we generated cell lines with both TP53 loss and 50% NAMPT loss. We found TP53 mutational status did not attenuate the observed effects of NAMPT inhibition on cell survival. Viability assays with primary patient AML samples confirmed that -7/del(7q) status imparts significantly elevated sensitivity to KPT 9274 treatment than samples with diploid chromosome 7 alleles. In summary, our findings reveal NAMPT heterozygosity as a therapeutic vulnerability in high-risk myeloid neoplasms that warrants clinical follow-up. Further, we provide a framework centered on data-mining for uncovering collateral lethal genes in other cancers with recurrent chromosomal arm level deletions.

AML with t(4;12)(q12;p13): A Detailed Genomic and Transcriptomic Analysis Reveals Genomic Breakpoint Heterogeneity, Absence of Pdgfra Fusion Transcripts and Presence of Pdgfra Overexpression in a Subset of Cases

Background: Gene fusions are a frequent event in acute myeloid leukaemia (AML). It is estimated that about 40% of AML patients harbour a cytogenetic abnormality resulting in a gene fusion. However, AML with t(4;12)(q12;p13) is very rare, but it is often accompanied by an aggressive clinical course and a poor prognosis. As frequently indicated by fluorescence in situ hybridization analyses (FISH), patients are assumed to harbor an ETV6::PDGFRA fusion, which impacts the choice of therapy, as these patients can be treated with tyrosine kinase inhibitors. The genomic region on chromosome 4 involved in ETV6 rearrangements is densly packed with genes in close spatial proximity. Therefore, the resolution of chromosome banding analysis and also FISH is not sufficient to fully elucidate the fusion partners involved. Recent studies have pointed out that many of these patients do not harbor an ETV6::PDGFRA fusion but other rather unknown fusion partners have been elucidated. Aim: (1) Evaluation of the genomic breakpoints in patients with t(4;12)(q12;p13) ETV6-rearranged AML; (2) determine the alteration of PDGFRA expression in patients with t(4;12). Patients and Methods: 10 patients (F: 4, M: 6; median age: 63 [44-82] years) with a t(4;12)(q12;p13) indicated by FISH and chromosome analysis were included. Samples were analysed by whole genome and whole transcriptome sequencing (WGS/WTS). Sequencing was performed on NovaSeq instrument (Illumina). Fusions were called with Arriba, STAR-Fusion and Manta. For gene expression analysis WTS data were log2 transformed and normalized with the trimmed mean of M-values (TMM) method. Results: Based on chromosome analysis and FISH patients showed break events in 4q12 and 12p13. In all cases a FISH signal constellation typical for an ETV6 rearrangement was observed. The mutation spectrum for each patient of the most commonly mutated genes in AML was examined by use of WGS data. The median number of mutations was 3, with mutations in ASXL1 being the most common (6 patients) and none of the patients featuring mutations in the PDGFRA gene. WTS analysis revealed in-frame fusions in 6 of 10 patients involving genes located on chromosomes 4 and 12 (4 patients with ETV6::CHIC2, 1 patients with ETV6::SCFD2, 1 patient with ETV6::ADAMTS3). None of the 10 examined patients showed a gene fusion, or a fusion transcript involving PDGFRA. Based on WTS data, 7 of the 10 patients showed a PDGFRA overexpression. WGS breakpoint analysis showed that genetic breakpoints on chromosome 12 cluster in introns 1 (4 patients) and 2 (6 patients) of the ETV6 gene. In contrast chromosome breaks on chromosome 4 are heterogeneously distributed in the 4q12 region. Breakpoint comparison indicated that patients with chromosome breaks in a range from chr4:54,804,230-54,962,206 (7 patients) display PDGFRA overexpression. In contrast patients with chromosome breaks further downstream chr4:55,021,511-73,409,362 (3 patients) did not exhibit an increased PDGFRA expression. This suggests an ectopic expression of PDGFRA triggered by the translocation and independent of the existence of an in-frame fusion transcript. A chromosome break in the range of chr4:54,804,230-54,962,206 (seen in 7 patients) might result in the inactivation of a CTCF binding site (chr4:54,796,345-54,796,360) upstream of these chromosome breaks that is already known to induce PDGFRA overexpression when disrupted. Conclusions: Analysis of AML with t(4;12)(q12;p13) translocation by WGS and WTS provides detailed information that separates two subsets distinguished by distinct breakpoint cluster regions on 4q12 and PDGFRA gene expression. The clinical impact of increased PDGFRA gene expression on response to TKI and prognosis as well as the presence of additional fusion transcripts has to be evaluated in further studies.

Single-Cell Proteogenomics Analysis of AML Samples Treated with Decitabine and Venetoclax Reveals Divergent Treatment Escape Mechanisms

Background: The combination therapy of hypomethylating agents and venetoclax (HMA+VEN) has emerged as a standard of care for acute myeloid leukemia (AML) patients unfit for intensive chemotherapy. Nonetheless, significant clinical challenges persist, including relapse and treatment resistance. Previous studies have revealed genetic ( RAS/RTK pathway mutations and TP53 mutations) and phenotypic (monocytic differentiation) resistance mechanisms in the context of HMA+VEN therapy. Despite these advancements, our comprehensive understanding of the HMA+VEN resistance mechanisms remains incomplete. To gain further insights into the resistance mechanism in HMA+VEN therapy, we implemented single-cell proteogenomics analysis on longitudinally collected samples from AML patients treated with decitabine+venetoclax (DAC+VEN) trial. Methods: We performed a high-throughput, single-cell targeted DNA-antibody sequencing (DAb-seq) using Tapestri platform from Mission Bio Inc. Sixty-three AML samples sequentially collected from 33 unique patients who participated in DAC+VEN clinical trial (NCT03404193) were analyzed. Our custom DNA panel covered 37 recurrently mutated genes in AML, whereas the custom antibody panel included either 15 cell surface proteins (N = 20 patients) or 48 proteins (N = 13 patients). Cellular phenotypes were inferred based on the patterns of cell surface protein expression. Median 2,767 cells were sequenced per sample, with total 196,719 cells sequenced for this study. Results: The median age of the cohort was 70 years (range 21-84). Twenty-four (73%) patients had primary AML and 9 (27%) had secondary or therapy-related AML. Based on the FAB classification, 13 patients had M0/M1/M2, 6 had M4/M5, one had M7, and the rest had unknown subtypes. The most frequent gene mutation at baseline was DNMT3A (45%), followed by NPM1 (39%), TET2 (30%), and TP53 (24%). Among the 33 patients, 32 had evaluable treatment response; 27 (82%) were defined as responders by achieving CR or CRi, whereas 5 (15%) were non-responders. Six patients experienced relapse after responding to the therapy, and their baseline-relapse pairs were analyzed by the single-cell platform. Using the composition of cellular phenotype data, AML samples were classified into either stem-like (N = 5), progenitor-like (N = 1), predominantly monocytic (N = 4), predominantly erythroid (N = 2) and mixed population AML (mixed population of stem, progenitor, monocyte or erythroid-like population, N = 21). Genotype-phenotype analysis showed a significant correlation between the KRAS mutation and the mixed phenotype (p= 0.0403), as well as between the U2AF1 mutation and the mixed phenotype (p= 0.0471). There was no significant association between treatment response and AML phenotype. Analysis of six baseline-relapse pairs showed that relapse was associated with phenotypic shift of AML cells. Stem-like cells were largely eradicated at relapse and replaced by more differentiated cells. Among the six baseline-relapse pairs, three showed monocytic shift, one showed erythroid shift and two showed mixed monocytic/erythroid shift. Phenotypic shifts at relapse were not always associated with expansion of new genetic mutations, except for in two cases: one had monocytic shift accompanied with expansion of KRAS mutation, and another had erythroid shift accompanied with expansion of NRAS mutation. Conclusions: Phenotypic transition from stem-like cells to more differentiated cells (either monocytic or erythroid) was frequently observed in AML relapse following DAC+VEN therapy. These findings are consistent with the known dependency of these cells on non-BCL-2 anti-apoptotic proteins such as MCL-1 and BCL-xL. Close monitoring of these phenotypic alterations throughout the course of HMA+VEN treatment may potentially facilitate the precise identification of cellular populations predisposed to relapse.

Development of Circulating Tumor DNA (ctDNA) for Molecular Measurable Residual Disease (MRD) in Acute Myeloid Leukemia (AML)

Introduction: Despite advances in therapeutic options, the majority of AML patients experience relapsed or refractory disease. Standard-of-care (SOC) methods for MRD detection (multiparametric flow cytometry and single gene or structural variant molecular assays) are hampered by (1) inadequate lower limits of detection (LOD), (2) paucity of recurrent mutations across AML genomes, (3) insufficient numbers of identified mutations to characterize clonal evolution, and/or (4) need for invasive bone marrow biopsy. Herein we develop and apply non-invasive circulating tumor DNA (ctDNA) liquid biopsies using a customized Cancer Personalized Profiling by Deep Sequencing (CAPP-Seq) approach to simultaneously quantify MRD and characterize clonal dynamics in AML. Methods: To increase the number of tumor-specific mutations per case for MRD detection and improve the LOD for ctDNA-MRD, we performed whole exome sequencing (WES) on purified blasts and paired T cells (latter as germline control) from 24 patients with AML (n = 20 previously untreated, n = 4 with relapsed/refractory disease) and designed personalized hybrid capture panels. We combined the personalized panels with a shared hybrid capture panel of 58 recurrently mutated (‘canonical‘) AML genes covering 225kB as a composite approach to generate patient-specific AML-CAPP-Seq assays. We applied AML-CAPP-Seq to track single nucleotide variants (SNVs) in 468 biological samples from the 24 AML patients and 21 healthy control subjects. We compared the performance of MRD detection in cellular (bone marrow mononuclear cell/BMMC, peripheral blood mononuclear cell/PBMC) and cell-free (BM-ctDNA, PB-ctDNA) compartments against SOC clinical MRD assays as well as patient specific clinical outcomes. Results: We observed a median of 30 SNVs (IQR 16.5-40.25) per patient from WES, compared to only 2 (IQR 1-3.25) if using the AML-focused canonical panel alone (p &amp;lt; 0.0001) ( Fig. 1A). This number of variants enabled sensitive molecular disease monitoring in 96% (23/24) of patients with a LOD of &amp;lt; 0.01% tumor fraction from typical quantities of cell-free DNA. In contrast, when using the canonical panel alone, only 83% (20/24) of patients had 1 or more SNV to allow MRD detection. Notably, only 12.5% (3/24) of patients in this cohort had a feature amenable to SOC molecular MRD methods. Upon comparing quantitative levels of MRD in each biological compartment, we found that tumor burden in PB-ctDNA, BM-ctDNA and BMMC samples were highly correlated (r &amp;gt; 0.92, p &amp;lt; 0.0001) with similar amounts of disease. Interestingly, PB-ctDNA contained quantitatively more tumor DNA than corresponding PBMC samples (p = 0.0002), most pronounced at low tumor burdens (median 8.2-fold enrichment when mean tumor allele fraction in PBMCs was &amp;lt; 1%). These results suggest that PB-ctDNA effectively captures total body BM disease and mutational burden in AML and serves as a superior analyte for MRD monitoring compared to PBMCs. When evaluating the performance of AML-CAPP-Seq against clinical SOC methods, our assay correctly detected molecular disease in 99.6% (237/238) of samples known to contain measurable disease, including 98.2% (54/55) of samples at timepoints of clinical MRD positivity during clinical remission (CR). However, restricting trackable SNVs to only ‘canonical’ genes led to significant degradation of performance. Specifically, only 69.1% (38/55) of samples with positive MRD during CR by clinical SOC assay were detected by ctDNA if canonical genes alone were employed (p = 0.0001). Intriguingly, when using the complete gene panel, AML-CAPP-Seq also identified molecular MRD in 37.5% (30/80) of samples with undetectable MRD by SOC assays. Finally, stratifying patients who achieved CR after 1st treatment line based on PB-ctDNA MRD significantly predicted relapse free survival (p = 0.046, hazard ratio (HR) = 4.5). Moreover, attaining an MRD negative CR in PB-ctDNA at any timepoint was strongly prognostic of overall survival (p = 0.0004, HR = 8.5) ( Fig. 1B). Conclusions: ctDNA is a promising biomarker for ultrasensitive detection and tracking of MRD in AML without need for invasive bone marrow assessment. Tracking mutations beyond canonical AML genes improves performance of such assays. ctDNA analysis has numerous areas of clinical utility, including response and relapse prediction, evaluation of clonal dynamics, and exploration of mechanisms of therapy resistance.

Identifying PTPRJ As a Novel Mediator of CEBPA-Mutated AML

10-20% of acute myeloid leukaemia (AML) cases in children and adults carry mutations in the transcription factor CCAAT/enhancer binding protein alpha (CEBPA). CEBPA is transcribed from a single exon and produces two isoforms, p30 and p42, with characteristic mutations, either frameshift mutations in the N-terminal portion ( CEBPA Nterm) leading to production of only the p30 isoform, or in frame mutations in the C-terminal portion ( CEBPA Cterm), disrupting DNA binding. The most frequent secondary driver mutation in CEBPA-mutated AML, is the second allele of CEBPA. Additionally, in rare germline CEBPA cases, the founding mutation is usually CEBPA Nterm, with allindividuals showing acquisition of a second hit mutation in the CEBPA Cterm on the alternate CEBPA allele at the time of AML diagnosis, which has near 100% penetrance in these families. This highlights a strong selective pressure for this very specific biallelic mutation pattern. We have developed zebrafish models with germline cebpa Nterm and cebpa Cterm mutations that faithfully recapitulates the disease, with all homozygous and double heterozygous mutants showing loss of mature myeloid cells, and impaired survival. All double or compound mutants die by 10 weeks of age, with haematopoietic stem and progenitor cell (HSPC) expansion, and leukaemia in around 30% of these animals. Our model also demonstrates distinct phenotypes for cebpa Nterm and cebpa Cterm mutations during developmental haematopoiesis prior to leukaemia onset. We observed that cebpa Nterm and cebpa Cterm mutations have opposite effects on the expression of c-myb, a transcription factor expressed by proliferating HSPC, from 3 days post fertilization. cebpa Nterm/Nterm mutants show an increase in c-myb while cebpa Cterm/Cterm show reduced c-myb expression during development. To uncover the mechanisms by which cebpa Nterm and cebpa Cterm effect HSPCs we undertook RNASeq of sorted Tg(cd41:eGFP) lo HSPCs from fish of all possible genotype combinations. We identified both shared and unique expression profiles between genotypes. We also identified 4 genes that that were differentially regulated in both cebpa Nterm/Nterm and cebpa Cterm/Cterm HSPC, but in opposing vectors (upregulated in cebpa Cterm/Cterm and downregulated in cebpa Nterm/Nterm) (Figure 1). We hypothesised that these 4 genes are candidate drivers of selective pressure for the common CEBPA Cterm/Ntermmutation combination in human AML, and thus the malignant phenotype it confers. One of these candidate genes, PTPRJ, has also recently been identified as a frequently mutated gene in CEBPA-mutated AML in children thereby validating the relevance of our dataset and our approach. To define the effects of these 4 candidate genes we then conducted an F0 CRISPR knock-out screen in all cebpa mutant combinations in our zebrafish model, using c-myb expression as a phenotypic readout. We identified ptprja as our primary candidate gene and showed that loss of ptprja alone and in combination with cebpa Cterm/+ reduced expression of c-myb but had no effect on expression of c-myb in cebpa Cterm/Cterm, indicating that ptprja loss reduces c- myb-expressing HSPC and that this is dependent on functional cebpa DNA binding. We then examined the impact of ptprja knockout in juvenile zebrafish. Homozygous and double heterozygous mutants develop a pre-leukaemia expansion of HSPC before they succumb to death. We showed that that loss of ptprja in cebpa Cterm/Cterm fish accelerates this pre-leukaemic expansion of Tg(cd41:eGFP) lo HSPCs in 4 week fish (Figure 2). We also showed an opposing effect in the cebpa Nterm/Nterm mutants at 2 weeks, where loss of ptprja resulted in decreased pre-leukemic expansion of HSPC. These data indicate a role for PTPRJ in mediating HSPC expansion in CEBPA-mutated AML and suggest that PTPRJ may mediate the mechanism of clonal selection in those with a CEBPA mutation that drives the acquisition of a second CEBPA mutation on the opposing allele, leading to the common CEBPA Cterm/Nterm in patients with CEBPA-mutated AML.

Childhood AML Combined with AML1-ETO Fusion Gene and c-KIT or Other Mutations Had Favorable Survival Treated By the C-Huanan AML 2015 Protocol: Study in Multicenter of South of China

Objective: To analyze the impact of AML1-ETO combined with other gene mutations on survival prognosis in children with acute myeloid leukemia (AML) who received the C-HUANAN AML 2015 protocol. Methods: Total 363 children with AML (non APL) who received chemotherapy only from 9 medical centers in South China from January 2015 to December 2020 were retrospective analyzed. The fusion genes and mutation genes spectrum in the bone marrow samples of these children were detected by the first generation and next generation gene sequencing methods. One hundred and fourteen patients had been detected the AML1-ETO fusion gene positive. All of them were treated with the C-HUANAN AML 2015 protocol including 2 groups in which each group contained 4 courses of chemotherapy(FLAG-IDA1,FLAG-IDA2,HAE MidAC versus DAE1,DAE2,HAE,MidAC). The impact of AML1-ETO fusion gene combined with other gene mutations on the prognosis and survival of children was analyzed. Result: A total of 114 AML patients with AML1-ETO fusion gene were included in this study, with a male to female ratio of 1.48:1 and a median age of 85.5 (7-169) months. Among them, there were 35 cases in the DAE group and 79 cases in the FLAG-IDA group. As of April 2021, with a median follow-up time of 21 months (1m-75ms ), 101 cases survived and 13 cases died. OS and EFS were 87.0 ± 3.4%, respectively, with EFS=85.0 ± 3.6%. There was no significant difference in overall survival (OS) and disease-free survival (EFS) between the DAE and FLAG-IDA group of (OS: 86.0 ± 6.5% vs 87.4 ± 4.0%)（ χ 2=0.000, P=0.995), EFS: 79.0 ± 7.6% vs 87.6 ± 3.9%（ χ 2=0.636, P=0.425). Survival analysis of AML1-ETO combined with c-KIT mutation negative or positive(n=33) showed no difference in prognosis (OS: 85.0 ± 4.2% vs 92.4 ± 5.3%)（ χ 2=0.967, P=0.325), EFS: 82.2 ± 4.5% vs 92.4 ± 5.3%（ χ 2=1.602, P=0.206); There was no difference in the prognosis between FLT3-ITD mutation negative and FLT3-ITD gene positive patients(n=8) (OS: 88.0 ± 3.4% vs 75.0 ± 15.3%)（ χ 2=1.516, P=0.218), EFS: 85.5 ± 3.7% vs 75.0 ± 15.3%（ χ 2=1.128, P=0.288); There was no difference in the prognosis between ASXL1 mutation negative and ASXL1 gene positive patients(n=14) (OS: 85.3 ± 3.8% vs 100.0%)（ χ 2=1.872, P=0.171), EFS: 83.0 ± 4.0% vs 100.0%（ χ 2=2.169, P=0.141); There was no difference in the prognosis between WT1 mutation negative and positive patients (n=34) (OS: 86.9 ± 3.9% vs 87.1 ± 7.0%)（ χ 2=0.156, P=0.693), EFS: 85.6 ± 4.0% vs 84.1 ± 7.3%（ χ 2=0.021, P=0.885); There was no difference in the prognosis between negative and positive NRAS mutations (n=13)(OS: 86.6 ± 3.6% vs 92.3 ± 7.4%)（ χ 2=0.033, P=0.856), EFS: 84.4 ± 3.9% vs 92.3 ± 7.4%（ χ 2=0.118，P=0.731). Conclusion: Combination of c-KIT or FLT3-ITD or ASXL1 or WT1 or NRAS gene mutations with AML1-ETO fusion gene in Childhood AML treated by the C-HUANAN AML protocol did not affected patients'survival.

Genomic Profiles and Associated Survival Prognosticators in Black Patients with Acute Myeloid Leukemia

Background Our knowledge of the genomics of acute myeloid leukemia (AML), which serves as the basis of clinically used prognostic biomarkers and therapeutic advances (including targeted therapies), is almost exclusively based on data from patients (pts) of European ancestry. Methods We analyzed the exomes and transcriptomes of 100 Black AML pts at diagnosis who received intensive induction chemotherapy on Alliance for Clinical Trials in Oncology (Alliance) protocols. African Ancestry was confirmed by SNP analysis. We established their genetic landscape including somatic gene mutations, structural variants, gene fusions and associated gene expression. Somatic mutation frequency was compared to whole-exome sequencing of 741 White pts at diagnosis from the Beat AML cohort analyzed by identical workflow. Survival of Black pts was compared to 1,519 White pts treated on the same Alliance protocols. Multivariable analysis was used to identify clinical and molecular features associated with outcomes. Results We identified 162 recurrently mutated genes in Black AML pts. We detected different mutation frequencies for AML-associated genes based on ancestry, and mutations in genes not previously implicated in AML, including PHIP alterations in 7% of this cohort. 38 genes were mutated in 3-5% of Black pts but in &amp;lt;1% of White pts . Of the 162 recurrently mutated genes in Black pts, only 41 (25%) were recurrently mutated in White pts, while 121 genes (75%) were mutated in ≤1 White patient. Only 1/741 White AML pts did not have a mutation in at least 1/ 56 recurrently mutated AML genes assessed by clinical NGS panels. By comparison, 10% of Black pts had no mutations in these genes. Analysis of gene fusions showed recurrent, cryptic CBFA2T3 fusions in 4 pts and a recurrent GGNBP2:: MYO19 fusion involving chromosome 17 not previously described in AML in 2 pts. The CBFA2T3 fusions did not cluster with CBF-AMLs by gene expression, suggesting biological differences. t-SNE visualization of gene expression showed that Black and White AML pts clustered together by known driver mutations. We identified a t-SNE cluster enriched for pts with myelodysplasia-related (MR) mutations. Notably, Black pts in this cluster were significantly younger than White pts [50 vs 58-years (y), p=0.04], suggestive of intrinsic and/or extrinsic dysplasia-causing stressors. When matched for age, performance status and study date, Black pts had higher relapse rates (63% vs 48%, p=0.05), worse disease-free (DFS, 3-y rates, 30% vs 47%, p=0.01) and overall survival (OS, 3-y rates, 31% vs 47%, p=0.007) compared to White pts. In a multivariable analysis, MR mutations (HR=2.06, p=0.03) and mutations in NPM1 (HR=2.29, p=0.009) and NRAS (HR=1.95, p=0.04) were associated with shorter DFS. Using the recently published iScore as a proxy for inflammation, we detected an enrichment of high inflammation in Black pts harboring NPM1 mutations compared to Whites (iScore high vs low; Black, 69% vs 31%, White, 45% vs 55%; p=0.08). Furthermore, when we classified pts into LSC17 prognostic groups, only 13% of Black pts in the prognostically favorable low LSC17 group were NPM1-mutated, compared with to 38% of White pts, suggesting ancestry-associated differences in the biological impact of NPM1 mutations. Mutations in IDH1/2 associated with shorter OS (HR=1.73, p=0.05) in Black pts identifying ancestry-specific risk markers. Finally, we show that the current ELN 2022 risk stratification system can be significantly improved by including NPM1, NRAS and IDH1/2 mutations as ancestry-specific adverse risk markers for Black pts ( Figure 2). Mutations in NPM1, NRAS, and IDH1/2 were enriched in a cohort of 43 Black relapsed/refractory (R/R)-AML pts via MSK-IMPACT supporting their adverse prognostic risk in Black pts. Conclusions Our work demonstrates ancestry-related differences in the genomic profiles of AML pts and calls for additional studies of ancestry-diverse populations to understand the landscape of somatic genetic alterations in AML. Further, our results emphasize the need to include ancestry-associated variants in clinical testing panels and to refine genetic risk assessment of AML by incorporating ancestry-specific prognostic biomarkers. Support: U10CA180821, U10CA180882, U24CA196171; Clinicaltrials.gov Identifiers: NCT00048958, NCT00899223, NCT00900224. https://acknowledgments.alliancefound.org.

Developing a novel SARS-CoV-2 risk index to predict the prognostic and therapeutic effects in acute myeloid leukemia

There is growing evidence of a strong association between SARS-CoV-2 and cancer prognosis and treatment outcome. However, there are no reliable SARS-CoV-2 assessment models to accurately predict prognostic and therapeutic effects in acute myeloid leukemia (AML). Here, differentially expressed genes associated with SARS-CoV-2 were detected, and multiple Cox regression methods were used to construct a SARS-CoV-2 risk index (SC2RI). Then, RT-qPCR was used to validate the gene expression levels in the AML samples. Finally, we explored how the SC2RI affected prognosis, immune infiltration, immunotherapy, and drug sensitivity in AML. We found that CYB5R3 and CLIP4 had been confirmed as hub genes in AML and were used to generate the SC2RI. The datasets indicated that the SC2RI had a superior predictive impact on the prognosis of AML. In addition, high expression of immune checkpoints and numerous immunological infiltrations were substantially correlated with a high SC2RI. However, it responded poorly to immune checkpoint blockade, which may be related to T-cell dysfunction, lack of effective antigens, and deficiency of synaptic capacity. Moreover, a high SC2RI was less susceptible to mTOR-related pathway medications but more sensitive to cell cycle suppressors. Therefore, categorization based on SC2RI could enhance the prognostic prediction of AML and help identify novel therapeutic approaches.

TET2 lesions enhance the aggressiveness of CEBPA-mutant acute myeloid leukemia by rebalancing GATA2 expression

The myeloid transcription factor CEBPA is recurrently biallelically mutated (i.e., double mutated; CEBPADM) in acute myeloid leukemia (AML) with a combination of hypermorphic N-terminal mutations (CEBPANT), promoting expression of the leukemia-associated p30 isoform, and amorphic C-terminal mutations. The most frequently co-mutated genes in CEBPADM AML are GATA2 and TET2, however the molecular mechanisms underlying this co-mutational spectrum are incomplete. By combining transcriptomic and epigenomic analyses of CEBPA-TET2 co-mutated patients with models thereof, we identify GATA2 as a conserved target of the CEBPA-TET2 mutational axis, providing a rationale for the mutational spectra in CEBPADM AML. Elevated CEBPA levels, driven by CEBPANT, mediate recruitment of TET2 to the Gata2 distal hematopoietic enhancer thereby increasing Gata2 expression. Concurrent loss of TET2 in CEBPADM AML induces a competitive advantage by increasing Gata2 promoter methylation, thereby rebalancing GATA2 levels. Of clinical relevance, demethylating treatment of Cebpa-Tet2 co-mutated AML restores Gata2 levels and prolongs disease latency.