Translating recent advances in the pathogenesis of acute myeloid leukemia to the clinic

Investigating the multifaceted cooperation of autophagy, PI3K/AKT signaling pathways, and INPP4B gene in de novo acute myeloid leukemia patients

BACKGROUND

Acute myeloid leukemia (AML) has been the most prevalent form of acute leukemia among adults, and it has been associated with poor survival rates over the last four decades. Understanding the processes involved in leukemogenesis, particularly autophagy and signaling pathways, can provide critical insights into their roles in disease development, risk assessment, and potential therapeutic interventions. This study investigated gene expression changes, focusing on MAP1LC3B and BECN1, related to autophagy, as well as PI3KCA and AKT1 in the PI3K-AKT pathway, and INPP4B, which regulates this signaling cascade.

METHODS

We collected blood samples from 21 AML patients and 9 healthy volunteers. Gene expression was analyzed through qPCR following RNA extraction and cDNA synthesis. Statistical analysis encompassed t-tests, ANOVA, and correlation coefficients.

RESULTS

AML patients exhibited significantly increased MAP1LC3B gene expression (****P < 0.0001; fold change = 11.9) and significantly reduced levels of INPP4B (****P < 0.0001; fold change = 0.026), AKT1 (*P < 0.05; fold change = 0.59), and PI3KCA (****P < 0.0001; fold change = 0.16) compared to healthy controls. However, BECN1 gene expression did not significantly differ between the two groups. Additionally, noteworthy correlations were observed between INPP4B and BECN1 (r = 0.57; P = 0.006) and BECN1 and PI3KCA (r = 0.61; P = 0.003) in AML patients.

CONCLUSIONS

This study highlights variations in leukemogenesis pathways, exemplified by increased MAP1LC3B expression and diminished expression of regulatory genes in specific AML cases. These findings contribute to our comprehension of the molecular mechanisms underlying AML and may inform future diagnostic and therapeutic approaches.

Identification and validation of STAT4 as a prognostic biomarker in acute myeloid leukemia

Acute myelogenous leukemia (AML) is a common malignancy and is supposed to have the ability to escape host immune surveillance. The present study aimed to identify key genes in AML that may affect tumor immunity and to provide prognosis biomarkers of AML. The Cancer Genome Atlas (TCGA) dataset was screened for transcription factors (TFs) involved in immunity and influencing survival, combining Gene Expression Omnibus (GEO) data to validate the impact on patient survival. A prognostic signature was established using four transcription factors, and these genes play an important role in the immune system, with higher regulatory T cell (Treg) scores in high-risk patients compared with the low-risk group. Analysis of individual genes showed that STAT4 and Treg are closely related, which may be due to STAT4 transcribing related genes that affect immunity. STAT4 expression was positively correlated with the proportion of abnormal cells and promoted AML recurrence as verified by AML clinical patient samples. In addition, silencing of STAT4 significantly slowed down the proliferation capacity of HL60 cells. In conclusion, these findings suggest that STAT4 may be a potential biomarker for AML prognosis. As a key gene affecting the prognosis of AML patients, STAT4 has the potential to be a candidate diagnostic and prognostic biomarker for AML.

Cytotoxic T-lymphocytes in acute myeloid leukemia: Monitoring prognosis and guiding treatment choice

BACKGROUND

Cytotoxic T-lymphocyte (CTL)-mediated therapy has become the central theme of cancer immunotherapy. The present study emphasized the role of CTLs in acute myeloid leukemia (AML) and aimed to understand the role of CTLs cytogenetic markers in monitoring AML prognostic outcomes and clinical treatment responses.

METHODS

Seurat was employed to analyze single-cell RNA sequencing data in GSE116256. CellChat was used to detect cell-cell interactions to determine the central role of CTLs. The marker genes of CTLs were extracted and randomForestSRC was employed to construct a random forest model. The prognosis, immune checkpoint expression, immune cell infiltration, immunotherapy response and drug sensitivity of AML patients were evaluated according to the model.

RESULTS

Seven types of cellular components of AML were identified in GSE116256, and CTLs radiated the most interactions with other cell types. Random forest analysis screened out six marker genes for construction of the model. The risk score calculated according to the model was positively correlated with immune score, immune cell infiltration, expression of multiple immune checkpoints and immune effect pathway. The response rate of immunotherapy was significantly higher and more sensitive to 14 drugs in high-risk samples than in low-risk samples, whereas low-risk patients showed a higher sensitivity to six drugs.

CONCLUSIONS

The present study emphasized the central role of CTLs in cell communication and established a random forest regression model based on its cytogenetic markers, which helps to stratify the prognosis of AML, promotes the understanding of the phenotype of AML and may also guide the treatment choice of AML patients, which contributed to stratification of AML prognosis, promoted understanding of the phenotype of AML and may guide treatment selection in patients with AML.

Combination of Ethacrynic Acid and ATRA Triggers Differentiation and/or Apoptosis of Acute Myeloid Leukemia Cells through ROS

BACKGROUND AND OBJECTIVE

All-trans retinoic acid (ATRA), an effective differentiation inducer, has been applied clinically to treat acute promyelocytic leukemia (APL). Unfortunately, it is not as potent in other kinds of acute myeloid leukemia (AML). Ethacrynic acid (EA), a classical powerful diuretic, can increase reactive oxygen species (ROS) contents, which can assist ATRA in inducing differentiation in AML cells. Here, we investigated the effect of EA combined with ATRA (EA+RA) on some AML cells except APL.

METHODS

Apoptosis and differentiation were determined by morphology, cell viability, Annexin-V assay and CD11c expression. Western blot analysis and the detection of ROS and mitochondrial transmembrane potentials (MMP) were used to investigate the mechanisms.

RESULTS

AML cells exhibited differentiation and/or apoptosis after EA+RA treatment. EA+RA increased the intracellular ROS contents. EA+RA-induced apoptosis was accompanied by MMP attenuation and caspase-3/7 activation. EA+RA-induced differentiation was along with MEK/ERK and Akt activation and increased expression of PU.1, CCAAT/enhancer-binding protein β (C/EBPβ) and C/EBPε. N-acetyl-L-cysteine (NAC), an antioxidant, thoroughly reduced EA+RA-increased ROS, and also inhibited MMP attenuation, the activation of caspase- 3/7, MEK/ERK and Akt pathways, the elevation of PU.1 and C/EBPs, and apoptosis and differentiation. However, MEK or PI3K specific inhibitors only suppressed EA+RA-triggered differentiation and the elevation of PU.1 and C/EBPs, but not ROS levels.

CONCLUSION

EA+RA induced cell apoptosis through ROS dependent MMP attenuation and caspase 3/7 activation while inducing differentiation by ROS-MEK/ERK-PU.1/C/EBPs and ROS-Akt-PU.1/C/EBPs pathways. In summary, it may provide innovative ATRA-based combination therapy strategies for AML patients via ROS.

A novel prognostic classification integrating lipid metabolism and immune co-related genes in acute myeloid leukemia

Background

As a severe hematological malignancy in adults, acute myeloid leukemia (AML) is characterized by high heterogeneity and complexity. Emerging evidence highlights the importance of the tumor immune microenvironment and lipid metabolism in cancer progression. In this study, we comprehensively evaluated the expression profiles of genes related to lipid metabolism and immune modifications to develop a prognostic risk signature for AML.

Methods

First, we extracted the mRNA expression profiles of bone marrow samples from an AML cohort from The Cancer Genome Atlas database and employed Cox regression analysis to select prognostic hub genes associated with lipid metabolism and immunity. We then constructed a prognostic signature with hub genes significantly related to survival and validated the stability and robustness of the prognostic signature using three external datasets. Gene Set Enrichment Analysis was implemented to explore the underlying biological pathways related to the risk signature. Finally, the correlation between signature, immunity, and drug sensitivity was explored.

Results

Eight genes were identified from the analysis and verified in the clinical samples, including APOBEC3C, MSMO1, ATP13A2, SMPDL3B, PLA2G4A, TNFSF15, IL2RA, and HGF, to develop a risk-scoring model that effectively stratified patients with AML into low- and high-risk groups, demonstrating significant differences in survival time. The risk signature was negatively related to immune cell infiltration. Samples with AML in the low-risk group, as defined by the risk signature, were more likely to be responsive to immunotherapy, whereas those at high risk responded better to specific targeted drugs.

Conclusions

This study reveals the significant role of lipid metabolism- and immune-related genes in prognosis and demonstrated the utility of these signature genes as reliable bioinformatic indicators for predicting survival in patients with AML. The risk-scoring model based on these prognostic signature genes holds promise as a valuable tool for individualized treatment decision-making, providing valuable insights for improving patient prognosis and treatment outcomes in AML.

Spatiotemporal evolution of AML immune microenvironment remodeling and RNF149-driven drug resistance through single-cell multidimensional analysis

BACKGROUND

The composition of the bone marrow immune microenvironment in patients with acute myeloid leukaemia (AML) was analysed by single-cell sequencing and the evolutionary role of different subpopulations of T cells in the development of AML and in driving drug resistance was explored in conjunction with E3 ubiquitin ligase-related genes.

METHODS

To elucidate the mechanisms underlying AML-NR and Ara-C resistance, we analyzed the bone marrow immune microenvironment of AML patients by integrating multiple single-cell RNA sequencing datasets. When compared to the AML disease remission (AML-CR) cohort, AML-NR displayed distinct cellular interactions and alterations in the ratios of CD4+T, Treg, and CD8+T cell populations.

RESULTS

Our findings indicate that the E3 ubiquitin ligase RNF149 accelerates AML progression, modifies the AML immune milieu, triggers CD8+T cell dysfunction, and influences the transformation of CD8+ Navie.T cells to CD8+TExh, culminating in diminished AML responsiveness to chemotherapeutic agents. Experiments both in vivo and in vitro revealed RNF149's role in enhancing AML drug-resistant cell line proliferation and in apoptotic inhibition, fostering resistance to Ara-C.

CONCLUSION

In essence, the immune microenvironments of AML-CR and AML-NR diverge considerably, spotlighting RNF149's tumorigenic function in AML and cementing its status as a potential prognostic indicator and innovative therapeutic avenue for countering AML resistance.

Ex Vivo Anti-Leukemic Effect of Exosome-like Grapefruit-Derived Nanovesicles from Organic Farming-The Potential Role of Ascorbic Acid

Citrus fruits are a natural source of ascorbic acid, and exosome-like nanovesicles obtained from these fruits contain measurable levels of ascorbic acid. We tested the ability of grapefruit-derived extracellular vesicles (EVs) to inhibit the growth of human leukemic cells and leukemic patient-derived bone marrow blasts. Transmission electron microscopy and nanoparticle tracking analysis (NTA) showed that the obtained EVs were homogeneous exosomes, defined as exosome-like plant-derived nanovesicles (ELPDNVs). The analysis of their content has shown measurable amounts of several molecules with potent antioxidant activity. ELPDNVs showed a time-dependent antiproliferative effect in both U937 and K562 leukemic cell lines, comparable with the effect of high-dosage ascorbic acid (2 mM). This result was confirmed by a clear decrease in the number of AML blasts induced by ELPDNVs, which did not affect the number of normal cells. ELPDNVs increased the ROS levels in both AML blast cells and U937 without affecting ROS storage in normal cells, and this effect was comparable to ascorbic acid (2 mM). With our study, we propose ELPDNVs from grapefruits as a combination/supporting therapy for human leukemias with the aim to improve the effectiveness of the current therapies.

Functional epigenomics: chromatin complexity untangled

The development of an epigenetics-focused, CRISPR-based high-content functional genomics screening platform provides insight into chromatin regulation and uncovers a potential strategy to treat an aggressive type of leukemia.

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.

Current landscape of translational and clinical research in myelodysplastic syndromes/neoplasms (MDS): Proceedings from the 1st International Workshop on MDS (iwMDS) Of the International Consortium for MDS (icMDS)

Biological events that contribute to the pathogenesis of myelodysplastic syndromes/neoplasms (MDS) are becoming increasingly characterized and are being translated into rationally designed therapeutic strategies. Herein, we provide updates from the first International Workshop on MDS (iwMDS) of the International Consortium for MDS (icMDS) detailing recent advances in understanding the genetic landscape of MDS, including germline predisposition, epigenetic and immune dysregulation, the complexities of clonal hematopoiesis progression to MDS, as well as novel animal models of the disease. Connected to this progress is the development of novel therapies targeting specific molecular alterations, the innate immune system, and immune checkpoint inhibitors. While some of these agents have entered clinical trials (e.g., splicing modulators, IRAK1/4 inhibitors, anti-CD47 and anti-TIM3 antibodies, and cellular therapies), none have been approved for MDS. Additional preclinical and clinical work is needed to develop a truly individualized approach to the care of MDS patients.

Immunotherapy in leukaemia

Leukaemia is the common name for a group of malignant diseases of the haematopoietic system with complex classifications and characteristics. Remarkable progress has been made in basic research and preclinical studies for acute leukaemia compared to that of the many other types/subtypes of leukaemia, especially the exploration of the biological basis and application of immunotherapy in acute myeloid leukaemia (AML) and B-cell acute lymphoblastic leukaemia (B-ALL). In this review, we summarize the basic approaches to immunotherapy for leukaemia and focus on the research progress made in immunotherapy development for AML and ALL. Importantly, despite the advances made to date, big challenges still exist in the effectiveness of leukaemia immunotherapy, especially in AML. Therefore, we use AML as an example and summarize the mechanisms of tumour cell immune evasion, describe recently reported data and known therapeutic targets, and discuss the obstacles in finding suitable treatment targets and the results obtained in recent clinical trials for several types of single and combination immunotherapies, such as bispecific antibodies, cell therapies (CAR-T-cell treatment), and checkpoint blockade. Finally, we summarize novel immunotherapy strategies for treating lymphocytic leukaemia and clinical trial results.

Classification of Acute Myeloid Leukemia by Cell-Free DNA 5-Hydroxymethylcytosine

Epigenetic abnormality is a hallmark of acute myeloid leukemia (AML), and aberrant 5-hydroxymethylcytosine (5hmC) levels are commonly observed in AML patients. As epigenetic subgroups of AML correlate with different clinical outcomes, we investigated whether plasma cell-free DNA (cfDNA) 5hmC could categorize AML patients into subtypes. We profiled the genome-wide landscape of 5hmC in plasma cfDNA from 54 AML patients. Using an unbiased clustering approach, we found that 5hmC levels in genomic regions with a histone mark H3K4me3 classified AML samples into three distinct clusters that were significantly associated with leukemia burden and survival. Cluster 3 showed the highest leukemia burden, the shortest overall survival of patients, and the lowest 5hmC levels in the TET2 promoter. 5hmC levels in the TET2 promoter could represent TET2 activity resulting from mutations in DNA demethylation genes and other factors. The novel genes and key signaling pathways associated with aberrant 5hmC patterns could add to our understanding of DNA hydroxymethylation and highlight the potential therapeutic targets in AML. Our results identify a novel 5hmC-based AML classification system and further underscore cfDNA 5hmC as a highly sensitive marker for AML.

Promoter methylation might shift the balance of Galectin-3 & 12 expression in de novo adult acute myeloid leukemia patients

Acute myeloid leukemia (AML) was reported as the most common type of leukemia among adults. Galectins constitute a family of galactose-binding proteins reported to play a critical role in many malignancies including AML. Galectin-3 and -12 are members of the mammalian galectin family. To understand the contribution of galectin-3 and -12 promoter methylation to their expression, we performed bisulfite methylation-specific (MSP)-PCR and bisulfite genomic sequencing (BGS) of primary leukemic cells in patients with de novo AML before receiving any therapy. Here, we show a significant loss of LGALS12 gene expression in association with promoter methylation. The lowest degree of expression was found in the methylated (M) group while the highest degree was in the unmethylated (U) group and the partially methylated (P) group expression lies in between. This was not the case with galectin-3 in our cohort unless the CpG sites analyzed were outside the frame of the studied fragment. We were also able to identify four CpG sites (CpG number 1, 5, 7& 8) in the promoter region of galectin-12; these sites must be unmethylated so that expression can be induced. As far as the authors know, these findings were not previously concluded in earlier studies.

Enhanced MCM5 Level Predicts Bad Prognosis in Acute Myeloid Leukemia

Acute myeloid leukemia (AML) is a fatal heterogeneous hematologic malignancy. There is an urgent need to identify potential biomarkers to better classify sufferers with bad outcomes that might need more advanced treatment. The objective of this study was to investigate prognostic indicators that predict the outcome of sufferers with AML. The datasets of AML sufferers including mRNA sequencing data and clinical information were acquired from GEO datasets (GSE38865) and TCGA datasets. Kaplan–Meier curves and Cox regression analysis to screen genes correlated to survival. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analyses biological process analysis were utilized in verifying the function of various genes. Sufferers with elevated MCM5 level exhibited a worse prognosis, according to the survival analysis. It was indicated through multivariate and univariate analysis that MCM5 level was an independent adverse prognostic element for over survival in AML sufferers based on GEO and TCGA datasets. Meanwhile, MCM5 level in AML samples was higher than in normal samples. Additionally, it was indicated through PPI network and functional enrichment analyses that through accelerating cell cycle and DNA replication, MCM5 promoted AML progression. In conclusions, MCM5 level was an independent poor prognostic element in AML sufferers based on GEO and TCGA datasets. This is the first time that MCM5 is reported to be a biomarker of poor prognosis in AML.

Allogeneic hematopoietic stem cell transplantation: lessons learned by a molecular immunologist/transplant patient

Much has been learned about the genes and pathways that contribute to a diverse array of hematopoietic malignancies and other hematopoietic diseases. However, for many of these diseases, an allogeneic hematopoietic stem cell (HSC) transplant remains the preferred treatment option. This opinion article provides the perspective of a molecular immunologist who became a transplant patient after many years studying basic mechanisms of blood cell development. Among many lessons learned were the magnitude of racial and ethnic disparities in donor registries, the substantial improvement in outcomes over time that were due to the collective impact of numerous advances, the benefits and limitations of genetic and clinical data, and the remarkably intricate balance between promoting graft-versus-disease activity of donor cells while suppressing graft-versus-host disease (GVHD).