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Expression of METTL3, a SAM dependent methyltransferase, which deposits m6A on mRNA is linked to poor prognosis in Acute Myeloid Leukaemia and other type of cancers. Down regulation of this epitranscriptomic regulator has been found to inhibit cancer progression. Silencing the methyltransferase activity of METTL3 is a lucrative strategy to design anticancer drugs. In this study 3600 commercially available molecules were screened against METTL3 using brute force screening approach. However, none of these compounds take advantage of the unique Y-shaped binding cavity of the protein, raising the need for de novo drug designing strategies. As such, 125 branched, Y-shaped molecules were designed by "stitching" together the chemical fragments of the best inhibitors that interact strongly with the METTL3 binding pocket. This results in molecules that have the three-dimensional structure and functional groups which enable it to fit in the METTL3 cavity like fingers in a glove, having unprecedented selectivity and binding affinities. The designed compounds were further refined based on Lipinski's rule, docking score and synthetic accessibility. The molecules faring well in these criteria were simulated for 100 ns to check the stability of the protein inhibitor complex followed by binding free energy calculation.Communicated by Ramaswamy H. Sarma.

Introduction: The introduction of venetoclax has revolutionized the treatment landscape of acute myeloid leukemia, offering new therapeutic opportunities. However, the clinical response to venetoclax varies significantly between patients, with many experiencing limited duration of response., Areas Covered: Identified resistance mechanisms include both intrinsic and acquired resistance to VEN. The former is associated with cell lineage and differentiation state. The latter includes dependency on alternative BCL-2 family anti-apoptotic protein(s) mediated by genetic, epigenetic, or post-translational mechanisms, mitochondrial and metabolic involvement, as well as microenvironment. Understanding these mechanisms is crucial for optimizing venetoclax-based therapies and enhancing treatment outcomes for patients with acute myeloid leukemia. This review aims to elucidate the primary mechanisms underlying resistance to venetoclax and explore current therapeutic strategies to overcome this challenge., Expert Opinion: In patients with venetoclax resistance, alternative options include targeted combination therapies tailored to individual cases based on cytogenetics and prior treatments. Many of these therapies require further clinical investigation to validate their safety and efficacy.

Objective: Acute myeloid leukemia (AML) stands out as a malignancy of the stem cell precursors of the myeloid lineage. Bone-marrow mesenchymal stem cell-derived exosomes (BMSC-exos) affect AML progression. We explored the effects and mechanism of BMSC-exos on AML cell proliferation and apoptosis., Methods: Human AML cells (MOLM-16, MV-4-11) and normal human hematopoietic cells (GM12878) cultured in vitro were treated with exos extracted from BMSCs that transfected with microRNA (miR)-139-5p-mimics, ovβ-catenin, or miR-139-5p-inhibitor. BMSC morphology was observed by a microscopy, and its adipogenic and osteogenic differentiation abilities were assessed by oil red O staining and alizarin red S staining. BMSC-exos were extracted by ultracentrifugation, and their morphology was observed by a transmission electron microscopy. BMSC-exos were identified by nanoparticle tracking analysis and Western blot. The binding sites between miR-139-5p and β-catenin were predicted by TargetScan database, and then validated by dual-luciferase reporter assay. mRNA levels of miR-139-5p and β-catenin, cell proliferation, and apoptosis were evaluated by RT-qPCR, CCK-8, and flow cytometry. The expressions of CD63, CD81, TSG101, and GRP94 and the proteins of β-catenin, Bax, and Bcl-2 were determined by Western blot., Results: miR-139-5p was poorly expressed in AML cell lines. miR-139-5p overexpression reduced AML cell viability/proliferation/Bcl-2 level, and raised apoptosis/Bax level. BMSC-exos repressed AML cell proliferation and promoted apoptosis via miR-139-5p. miR-139-5p targeted to inhibit β-catenin expression. Subsequently, up-regulated β-catenin partially counteracted the effects of miR-139-5p in BMSC-exos on AML cell proliferation and apoptosis., Conclusion: BMSC-exos targeted to repress β-catenin expression by miR-139-5p, limited AML cell proliferation and facilitated apoptosis.

Background: Acute myeloid leukemia (AML) is a disease characterized by the proliferation of abnormal cells originating from blood stem cells. Understanding the pathogenesis and progression of AML, as well as identifying molecular markers for early diagnosis and prognosis assessment, is of paramount importance., Methods: The AML dataset was obtained from the Cancer Genome Atlas (TCGA), while the normal sample dataset was derived from the Genotype-Tissue Expression(GTEx) dataset. Furthermore, the association between SRSF12 expression and drug response was assessed using the Cancer Therapeutic Response Portal (CTRP) database to evaluate its potential therapeutic value. Finally, SRSF12 expression in AML cells was measured using quantitative real-time PCR (qRT-PCR)., Result: The difference in SRSF12 expression between 13 types of tumors and normal tissue samples was found to be statistically significant ( P  < 0.05). SRSF12 exhibited predominantly high expression in AML, indicating its potential as a diagnostic and prognostic marker for AML patients. High expression of SRSF12, along with age and cytogenetic risk, emerged as independent predictors of favorable prognosis in AML patients ( P  < 0.05). PCR demonstrated a significant increase in SRSF12 expression in AML patients., Conclusion: Overall, our findings suggest that the high expression of SRSF12 in AML patients is a poor prognostic factor, which may provide a new option for the diagnosis, and targeted therapy of AML.

Acute myeloid leukemia (AML) is a common hematologic malignancy in adults. Recent studies investigating the potential pathogenesis of AML have significantly advanced our understanding of this disease. While cytogenetics and molecular abnormalities are crucial for confirming chemotherapy response and long-term outcomes, there are additional potential therapeutic targets and prognostic factors. The CAPN1 gene, which encodes a large subunit of the ubiquitous enzyme calpain, has not been extensively studied in hematological diseases. In this study, we used data from the TCGA public database to perform a bioinformatic analysis and found that CAPN1 is differentially expressed in multiple cancers and is associated with an unfavorable prognosis in AML. We employed R software and websites such as David and STRING to conduct differential analysis, GO and KEGG analysis, and explore the correlation between CAPN1 and physiological processes and key pathways. Our findings suggest that CAPN1 is significantly associated with the structure of the extracellular matrix and receptor-ligand interactions, indicating its potential role in disease progression. Additionally, we used CYBERSORT and ssGSEA to analyze the immune environment of CAPN1 and found that it is associated with most immune components, particularly CD56 cells and neutrophils. In conclusion, CAPN1 is a key prognostic gene in AML that is significantly correlated with disease progression, clinical features, and immune invasion.

Background: This study aimed to explore the effect and mechanism of SCN5A overcoming ATP-binding cassette (ABC) transporter-mediated multidrug resistance (MDR) in acute myeloid leukemia (AML) through promoting apoptosis., Research Design and Methods: The tissues derived from AML patients were divided into Sensitive group and Resistance group according to the presence of drug-resistance. Human AML cell line HL-60 and drug-resistant strain HL-60/ADR were divided into HL-60/ADR-vector group, HL-60/ADR-SCN5A group, HL-60-vector group and HL-60-SCN5A group. RT-qPCR was used to detect the mRNA expression level of SCN5A; MTT assay to assess the survival rate and proliferation level of cells; flow cytometry to determine the apoptosis level; and western blot to check the levels of SCN5A, P-glycoprotein (P-gp), MDR protein 1 (MRP1), MDR gene 1 (MDR1), breast cancer resistance protein (BCRP), Bcl-2-associated X protein (Bax), and B-cell lymphoma 2 (Bcl-2) proteins in cells., Results: SCN5A expressed lowly in drug-resistant AML tissues and cells. Up-regulation of SCN5A inhibited MDR in HL-60 cells, enhanced the chemosensitivity of HL-60/ADR, and increased the apoptosis levels of HL-60 and HL-60/ADR cells. However, over-expression of SCN5A inhibited the expression of MDR-related proteins., Conclusions: SCN5A may overcome ABC transporter-mediated MDR in AML through enhancing the apoptosis and inhibiting the expression of MDR proteins.

Objective: Anthracyclines and cytarabine have comprised standard induction therapy for acute myeloid leukemia (AML) for decades. Low overall survival of AML is due to non-remission or relapse after remission. Hypomethylating agent (HMA) decitabine combined with low-dose chemotherapy or other targeted agents has shown promising effect for AML in clinical trials, especially in t (8;21) acute myeloid leukemia. We previously investigated histone deacetylase inhibitor (HDACi) chidamide could regulate Wnt/β-catenin signaling pathway in leukemia cell lines., Methods: Adult patients with de novo or relapsed/refractory AML who were treated with chidamide and decitabine in combination with chemotherapy (chidamide group, n  = 23) or only decitabine combination with chemotherapy (decitabine group, n  = 17) were analyzed., Results: Chidamide group represented higher complete response rate (82.6% and 52.9%, p =  0.0430, vs. decitabine group), progression-free survival and overall survival rates ( p  = 0.0088 and p  = 0.0139, respectively), especially for patients with de novo AML. Hematological toxicity and infections were the most common adverse events (AEs) in both groups, and they were manageable by supportive treatments., Conclusions: This HDACi- and HMA-based protocol is an effective and tolerable therapy for patients with AML. The comprehensive mechanism and effects of chidamide in combination with decitabine are worth to be further explored in AML.

Objective: SET domain containing protein 2 (SETD2) involves in the progression and development of chemotherapy resistance in acute myeloid leukemia (AML). Hence, this study aimed to investigate the relationship of SETD2 expression with disease risk, features, treatment response, and survival profile in AML., Methods: One-hundred and sixty primary AML patients were retrospectively analyzed. Their bone marrow (BM) samples before and after induction therapy were retrieved for SETD2 detection by RT-qPCR. Moreover, SETD2 expression in BM samples of 20 disease controls (DCs) were also determined., Results: SETD2 expression was downregulated in AML patients compared to DCs ( P  < 0.001). Higher SETD2 expression related to white blood cells ≤10 × 10 9 /L despite not reaching statistical significance ( P  = 0.062). One-hundred and nineteen (74.4%) AML patients achieved complete response (CR), while the remaining 41 (25.6%) did not achieve that. Furthermore, increased SETD2 expression was associated with CR achievement ( P  = 0.015). Survival analyses displayed that SETD2 high (vs. low) was related to prolonged event-free survival (EFS) ( P  = 0.001) and overall survival (OS) ( P  = 0.021). Moreover, increased SETD2 quartile was correlated with favorable EFS ( P  = 0.004) and OS ( P  = 0.042). After adjustment using multivariate Cox's regression analysis, higher SETD2 quartile was independently related to prolonged EFS [hazard ratio (HR): 0.766, P  = 0.013] and OS (HR: 0.669, P  = 0.013). It was also noticed that SETD2 expression was elevated during the induction therapy ( P  < 0.001)., Conclusion: Detection of SETD2 may assist in estimating treatment response and survival profile in AML patients.

Objective: Acute myeloid leukemia (AML) is a common blood cancer associated with poor prognosis and high mortality. In this study, we investigated the role and underlying mechanism of action of circ&#95;0104700 in the pathogenesis of AML., Methods: Circ&#95;0104700 was screened from the GEO database and detected in AML samples and cell lines. The effect of circ&#95;0104700 on AML was analyzed using a methylcellulose colony assay, CCK-8 assay, and cell cycle and apoptosis analyses. The mechanism was explored using bioinformatic analysis, quantitative reverse transcription-PCR, dual-luciferase reporter assays, northern blotting and western blot analysis in AML cells., Results: Circ&#95;0104700 expression was higher in AML patients and AML cell lines. Functionally, circ&#95;0104700 depletion attenuated cell viability and induced apoptosis in MV-4-11 and Kasumi-1 cells. Circ&#95;0104700 depletion enhanced the G0/G1-phase proportion but reduced the proportion of S-phase cells in MV-4-11 and Kasumi-1 cells. circ&#95;0104700 served as a competing endogenous RNA of miR-665 and enhanced MCM2 expression by sponging miR-665 in MV-4-11 and Kasumi-1 cells. Silencing circ&#95;0104700 repressed the proliferation and cell cycle and induced apoptosis of MV-4-11 and Kasumi-1 cells by inhibiting miR-665. MCM2 depletion alleviated the proliferation and cell cycle and enhanced the apoptosis of MV-4-11 and Kasumi-1 cells by inactivating JAK/STAT signaling. JAK/STAT signaling was involved in circ&#95;0104700-mediated malignant phenotypes of MV-4-11 and Kasumi-1 cells., Conclusion: circ&#95;0104700 contributed to AML progression by enhancing MCM2 expression by targeting miR-665. Our findings provide novel potential therapeutic targets for AML, including circ&#95;0104700, miR-665, and MCM2.

Objective: Older patients with acute myeloid leukemia (AML) face a higher risk of death. This study analyzed the gene sequencing results of an elderly AML patient to provide new ideas for treatment., Methods: This study performed single-cell RNA sequencing (scRNA-seq) bioinformatics analysis of blood cells in the peripheral blood and bone marrow of a 64-year-old AML-M5 patient before chemotherapy. The differentially expressed genes (DEGs) were identified, and functional enrichment analyses were performed., Results: A total of 7990 and 123 DEGs were identified in monocytes and hematopoietic stem cells (HSCs), respectively. Among the top 40 DEGs analyzed, MYB showed high expression in peripheral blood monocytes, while 13 other tumor-related genes exhibited high expression in monocytes in the bone marrow. Peripheral blood and bone marrow HSCs had 6 and 12 highly expressed tumor-related genes respectively, including MCL1 , JUN , and JUNB . These genes may form a interconnected network contributing to the progression and heterogeneity of AML, which can have an impact on patient treatment and prognosis., Conclusions: In conclusion, when treating elderly AML patients, it is important to consider their individual characteristics in order to optimize treatment strategies.

Dihydroorotate dehydrogenase (DHODH) remains as an active target at the preclinical level against acute myeloid leukemia (AML). Herein we report potent second generation benzylidene chromanone (SBL-105) analogues to inhibit DHODH in AML cells. Virtual docking and molecular dynamic simulations were performed. Human-recombinant (rh)DHODH, THP-1, TF-1 and HL-60 cell lines were used. MTT assay was used for cell viability. Flow cytometry was used for differentiation analysis. Computational modeling and simulations predict, SBL-105 analogs bind efficiently to DHODH with improved binding energies. While all tested analogues of SBL-105 inhibited rh DHODH enzyme, SBL-105-4 and SBL-105-6 more effectively inhibited rh DHODH with an IC 50 value of 3.62 and 13.61 nM respectively. SBL-105-4 exhibited excellent anti proliferative effects against THP-1, TF-1 and HL-60 cells with GI 50 values of 18.78, 38.11 and 63.83 nM respectively. A similar effect was also observed in SBL-105-6 treated AML cells with respective GI 50 values of 34.56, 44.40 and 38.65 nM in THP-1, TF-1 and HL-60 cells. An increase in apoptotic populations were enumerated in all three AML cells. Both these compounds also increased the differentiation marker CD11b positive populations in all the three AML cells tested. In conclusion, SBL-105-4 and SBL-105-6 were identified as potent second generation DHODH inhibitors, which drives attention for further preclinical developments.Communicated by Ramaswamy H. Sarma.

In acute myeloid leukemia (AML), leukemia stem cells (LSCs) have self-renewal potential and are responsible for relapse. We previously showed that, in Mll-AF9/NRAS G12V murine AML, CD69 expression marks an LSC-enriched subpopulation with enhanced in vivo self-renewal capacity. Here, we used CyTOF to define activated signaling pathways in LSC subpopulations in Mll-AF9/NRAS G12V AML. Furthermore, we compared the signaling activation states of CD69 High and CD36 High subsets of primary human AML. The human CD69 High subset expresses low levels of Ki67 and high levels of NFκB and pMAPKAPKII. Additionally, the human CD69 High AML subset also has enhanced colony-forming capacity. We applied Bayesian network modeling to compare the global signaling network within the human AML subsets. We find that distinct signaling states, distinguished by NFκB and pMAPKAPKII levels, correlate with divergent functional subsets, defined by CD69 and CD36 expression, in human AML. Targeting NFκB with proteasome inhibition diminished colony formation.

Metallothioneins (MTs) are a group of low-molecular weight cysteine-rich proteins that play vital roles in oxidative stress, metal homeostasis, carcinogenesis and drug resistance. However, few studies have analyzed the roles of MTs in acute myeloid leukemia (AML). In this study, we revealed that the expression of metallothionein1X (MT1X), a main isoform of MTs, was highly expressed and acted as a candidate of prognostic indicator in AML patients. In vitro cell function experiments verified that silencing MT1X inhibited the proliferation of AML cells, sensitized cells to doxorubicin, and increased their apoptosis. We also showed that the downregulation of MT1X expression suppressed nuclear factor-κB (NF-κB) signaling by reducing p65, p-IκB-α, and downstream effectors. Elevated p65 and MT1X levels were indicators in AML. Moreover, we revealed that miR-376a-3p had binding sites with 3'-UTR of MT1X, suggesting that MT1X was negatively regulated by miR-376a-3p. Cell functional assay results indicated that miR-376a-3p overexpression significantly inhibited the proliferation, arrested the AML cells in the G0/G1 phase and induced cell apoptosis. The rescue experiments further confirmed that miR-376a-3p could reverse the promotion of MT1X overexpression on the progress of AML cells. Taken together, our results revealed that elevated MT1X expression might be involved in the mechanism underlying AML progression, indicating that the miR-376a/MT1X axis might serve as a promising novel target for the effective treatment of patients with AML.

Myelodysplastic syndromes (MDS) and their progression to secondary acute myeloid leukemia (sAML) are associated with an altered protein expression including extracellular matrix (ECM) components thereby promoting an inflammatory environment. Since the role of the proteoglycan biglycan (BGN) as an inflammatory mediator has not yet been investigated in both diseases and might play a role in disease progression, its expression and/or function was determined in cell lines and bone marrow biopsies (BMBs) of MDS and sAML patients and subpopulations of MDS stem cells by Western blot and immunohistochemistry. The bone marrow (BM) microenvironment was analyzed by multispectral imaging, patients' survival by Cox regression. ROC curves were assessed for diagnostic value of BGN. All cell lines showed a strong BGN surface expression in contrast to only marginal expression levels in mononuclear cells and CD34 + cells from healthy donors. In the MDS-L cell line, CD34 - CD33 + and CD34 + CD33 + blast subpopulations exhibited a differential BGN surface detection. Increased BGN mediated inflammasome activity of CD34 - CD33 + TLR4 + cells was observed, which was inhibited by direct targeting of BGN or NLRP3. BGN was heterogeneously expressed in BMBs of MDS and sAML, but was not detected in control biopsies. BGN expression in BMBs positively correlated with MUM1 + and CD8 + , but negatively with CD33 + TLR4 + cell infiltration and was accompanied by a decreased progression-free survival of MDS patients. BGN-mediated inflammasome activation appears to be a crucial mechanism in MDS pathogenesis implicating its use as suitable biomarker and potential therapeutic target. Abbreviations: Ab, antibody; alloSCT, allogenic stem cell transplant; AML, acute myeloid leukemia; BGN, biglycan; BM, bone marrow; BMB, bone marrow biopsy; casp1, caspase 1; CTLA-4, cytotoxic T lymphocyte-associated protein 4; DAMP, danger-associated molecular pattern; ECM, extracellular matrix; FCS, fetal calf serum; GAPDH, glyceraldehyde-3-phosphate dehydrogenase; HD, healthy donor; HSPC, hematopoietic stem and progenitor cell; HSC, hematopoietic stem cell; IFN, interferon; IHC, immunohistochemistry; IL, interleukin; MDS, myelodysplastic syndrome; MPN, myeloproliferative neoplasm; MSI, multispectral imaging; NGS, next-generation sequencing; NLRP3, NLR family pyrin domain containing 3; OS, overall survival; PBMC, peripheral blood mononuclear cell; PD-1, programmed cell death protein 1; PD-L1, programmed death-ligand 1, PFS, progression-free survival; PRR, pattern recognition receptor; SC, stem cell; SLRP, small leucine-rich proteoglycan; TGF, transforming growth factor; TIRAP, toll/interleukin 1 receptor domain-containing adapter protein; TLR, toll-like receptor; Treg, regulatory T cell., Competing Interests: The authors declare that they have no conflicts of interest., (© 2022 The Author(s). Published with license by Taylor & Francis Group, LLC.)

Background: FAM230B serves as an oncogenic lncRNA in both gastric cancer and papillary thyroid cancer, while its role in acute myeloid leukemia (AML) is unclear. We predicted that FAM230B could be a target of miR-140, a well-characterized tumor suppressor, and analyzed their interaction in AML., Methods: Differential expressions of FAM230B and miR-140 in bone marrow mononuclear cells (BMMNCs) were determined by RT-qPCR. Correlations were analyzed by Pearson's correlation coefficient. Subcellular FAM230B location was determined using cellular fractionation assay. The direct interaction between FAM230B and miR-140 was confirmed by RNA pull-down assay. The roles of FAM230B and miR-140 in cell proliferation were explored using BrdU assay., Results: High FAM230B expression level and low miR-140 expression level were observed in AML. FAM230B and miR-140 were inversely correlated and directly interacted with each other. FAM230B could be detected in both cytoplasm and nuclear samples. MiR-140 overexpression downregulated FAM230B expression and suppressed the enhancing effects of FAM230B overexpression on cell proliferation., Conclusion: MiR-140 may target FAM230B to suppress cell proliferation in AML.

Background: Besides the traditional roles of HBA1 and HBB, recent findings suggest that hemoglobin genes may have roles in other contexts., Objective: In the present study, we aim to investigate a possible tumor-suppressor role of HBA1 and HBB in acute myeloid leukemia., Methods: Quantitative real-time PCR (RT-qPCR) was performed to detect the expression levels of HBA1 and HBB in acute myeloid leukemia patients and AML cell lines. The transfected cells were analyzed for Cell Counting Kit-8 (CCK-8), apoptosis, and cell cycle assay., Results: HBA1 and HBB genes were significantly decreased in acute myeloid leukemia patients and AML cell lines. Furthermore, in vitro approaches showed that overexpression of HBA1 and HBB inhibited proliferation, induced cell apoptosis, and blocked cell cycle process at the G2/M phase in K562 cells., Conclusion: Our data indicated that HBA1 and HBB genes may be potential tumor-suppressor genes in acute myeloid leukemia.

Background: : Acute myeloid leukemia (AML) is regarded as a haematological malignancy and seriously threatens the public's health. Circular RNA (circRNA) is gradually confirmed to be involved in the development of AML. The purpose of this study was to disclose the role of circRNA Potassium Voltage-Gated Channel Subfamily Q Member 5 (circ&#95;KCNQ5) in AML., Methods: : Quantitative real-time PCR (qPCR) and western blot were used for expression analysis. Colony formation assay, EdU assay and MTT assay were performed to determine cell proliferation. Flow cytometry assay was conducted to determine cell apoptosis. The predicted binding relationship between miR-622 and circ&#95;KCNQ5 or RAS oncogene family member 10 (RAB10) was verified by dual-luciferase reporter assay., Results: : The expression of circ&#95;KCNQ5 was increased in bone marrow samples of childhood AML patients and AML cell lines. The knockdown of circ&#95;KCNQ5 largely suppressed AML cell proliferation and promoted cell apoptosis. Circ&#95;KCNQ5 directly bound to miR-622 and inhibited miR-622 expression. The cotransfection of miR-622 inhibitor reversed the effects of circ&#95;KCNQ5 knockdown and thus recovered cell proliferation and depleted cell apoptosis. RAB10 was a target of miR-622, and circ&#95;KCNQ5 bound to miR-622 to increase the expression of RAB10. MiR-622 restoration inhibited AML cell proliferation and induced cell apoptosis, while RAB10 overexpression abolished these effects., Conclusion: : Circ&#95;KCNQ5 high expression was associated with childhood AML malignant development, and circ&#95;KCNQ5 participated in AML progression by regulating the miR-622/RAB10 pathway.

Objectives: To investigate the performance of H22954, a novel long non-coding RNA (lncRNA), in inhibiting glucose uptake in leukemia cells., Methods: 18 F-FDG uptake, RNA half-life quantitative real-time polymerase chain reaction (qRT-PCR) and luciferase assays were performed to detect the glucose uptake in the condition of leukemia. Microarrays and qRT-PCR analyses were used to identify the related genes or proteins and elucidate the underlying these processes., Results: H22954, a novel lncRNA, inhibited glucose uptake in leukemia cells. Using bioinformatics and microarray analyses, GLUT10 was identified as a possible target molecule of H22954. H22954 targeted the 3'untranslated region of GLUT10. In the luciferase assay, the luciferase activity of pGL3-GLUT10 was inhibited by H22954. Consistently, H22954 expression levels were inversely correlated with GLUT10 expression in cell lines and acute myeloid leukemia (AML) samples. Conversely, the degradation rate of GLUT10 mRNA was increased after H22954 overexpression. Moreover, glucose uptake was recovered when the GLUT10-interaction sites in H22954 were mutated., Conclusion: The lncRNA H22954 regulated GLUT10 expression to inhibit glucose uptake in leukemia cells. Our findings provide potentially valuable data for designing new targeted strategies based on H22954.

The vacuoles in Saccharomyces cerevisiae are the key players digesting the waste within the cell. This functional organelle corresponding to the lysosome of mammalians contains acidic hydrolases and specific membrane proteins. Vacuoles have more than 60 hydrolytic enzymes and can easily be modified by genetic engineering. In previous study, we optimised the encapsulation condition with appropriate time and concentration and confirmed the use of vacuole as drug delivery carrier for acute myeloid leukaemia treatment. In this study, recombinant vacuole that could target the acute myeloid leukaemia cell line was constructed. The vacuoles derived from genetic engineered yeast were decorated with targeting peptide that has specific affinity with TLR2 on AML cell membrane. The anti-cancer efficacy of AML targeting vacuoles carriers with encapsulated daunorubicin was shown to be higher than normal vacuole carriers and the crude daunorubicin. The results confirmed that target selective chemotherapy using the vacuole drug delivery system is effective and offers potential for cancer therapy.

Background: Acute myeloid leukemia (AML) is one of the most common malignant myeloid diseases in adults with a dismal prognosis. We aimed to explore the effects of circNFIX on the proliferation and apoptosis of AML cells., Methods: The expressions of circNFIX, miR-876-3p and tripartite motif (TRIM) 31 in the bone marrow specimens of AML patients and AML cell lines were detected by qRT-PCR or western blot. Cell proliferation was evaluated by 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) and 5-ethynyl-29-deoxyuridine (EdU) assays. Cell cycle and apoptosis were analyzed by flow cytometry. Western blot was used to detect protein expression. The relationship between miR-876-3p and circNFIX or TRIM31 was identified by dual-luciferase reporter assay or RNA pull-down assay., Results: The expression level of circNFIX was significantly increased in the bone marrow samples of AML patients and AML cells when compared with normal controls. CircNFIX silencing inhibited AML cell proliferation and promoted apoptosis. Inhibition of miR-876-3p reversed the effect of circNFIX knockdown on AML cell progression. In addition, circNFIX indirectly regulated TRIM31 through miR-876-3p. Further, TRIM31 overexpression counteracted the effect of circNFIX silencing on AML cell proliferation and apoptosis., Conclusion: CircNFIX knockdown could suppress the proliferation and induce the apoptosis of AML cells by targeting the miR-876-3p/TRIM31 axis.

Objective: To determine the role of replication factor C subunit 5 (RFC5) in acute myeloid leukemia (AML) from four aspects: expression, prognosis, biological functions, and its effects on the immune system., Methods: The RFC5 gene expression and survival analyses, biological function analyses including functional enrichment analysis of genes co-expressed with RFC5, RFC5-interacted gene network construction, gene set enrichment analysis (GSEA), and immune infiltration analysis were performed using data based on GDC TCGA and GEO. The CIBERSORT algorithm was employed to quantify immune cell fractions. All the statistical analyses were performed in SPSS software, GraphPad Prism, and R software., Results: RFC5 expression was abnormally expressed in AML ( P <0.05). Notably, differential RFC5 expression was observed among different FAB AML subtypes and hematopoietic lineages (all P <0.05). More importantly, high RFC5 expression served as an independent prognostic factor for the poor overall survival of AML patients ( P <0.001). Enrichment analyses revealed that RFC5 was involved in cell cycle-related pathways in AML. CIBERSORT analysis showed high proportions of M2 macrophages in the high RFC5 expression group., Conclusions: RFC5 might serve as an effective and robust biomarker for the diagnosis and prognosis of AML. RFC5 might be involved in the AML progression via cell cycle regulation. Moreover, the correlation between RFC5 and immune cells might provide potential assistance for AML treatment.

Objective: The aim of this study was to determine the biological function of Sprouty 1 (SPRY1) on acute myeloid leukemia (AML), and to investigate the potential mechanism., Methods: The expression of SPRY1 and the prognostic values of SPRY1 were assessed through the analysis of the Cancer Genome Atlas. Meanwhile, the expression of SPRY1 in AML cells was determined by qRT-PCR and western blot. Then, the biological function of SPRY1 on the proliferation, cell cycle and apoptosis in K-562 and HL-60 cells were tested using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay, colony-formation assay, 5-ethynyl-20-deoxyuridine assay and flow cytometry. Additionally, the protein expressions were measured by western blot., Results: We found that SPRY1 was markedly overexpressed in the cells of the patients with AML, and the patients with AML having a high SPRY1 expression has a bad prognosis. The proliferation and cell cycle progression in K-562 and HL-60 cells were notably promoted by SPRY1 overexpression, but inhibited by SPRY1 knockdown. Meanwhile, the apoptosis of K-562 and HL-60 cells was significantly repressed by SPRY1 overexpression and facilitated by SPRY1 knockdown. In addition, we found that SPRY1 overexpression significantly activated the Hedgehog pathway in AML cells. The function of SPRY1 on the proliferation, cell cycle and apoptosis was reversed by Gli1 in K-562 and HL-60 cells., Discussion: Identifying new biomarkers and exploring the pathogenesis of AML is urgent to improve the disease surveillance for patients with AML., Conclusions: SPRY1 could facilitate cell proliferation and cell cycle progression, and suppress cell apoptosis via activating the Hedgehog pathway in AML.

Background: Circular RNA (circRNA) regulates the pathogenesis of acute myeloid leukemia (AML). However, the mechanism of circRNA protein tyrosine kinase 2 (circPTK2) in AML remains unclear., Methods: Quantitative real-time polymerase chain reaction (qRT-PCR) assay was adopted for circPTK2, miR-582-3p and alpha-1,3-mannosyltransferase (ALG3) mRNA levels. 3-(4, 5-Dimethyl-2-thiazolyl)-2, 5-diphenyl-2- H -tetrazolium bromide (MTT) assay, and 5'-ethynyl-2'-deoxyuridine (EdU) assay were conducted for cell proliferation. Flow cytometry analysis was employed for cell apoptosis and cell cycle process. The glycolysis level was estimated by specific commercial kits. Western blot assay was utilized for protein levels. Dual-luciferase reporter assay and RNA immunoprecipitation (RIP) assay were performed to verify the interaction between miR-582-3p and circPTK2 or ALG3., Results: CircPTK2 level was enhanced in AML peripheral blood samples and cells. CircPTK2 knockdown restrained AML cell proliferation and glycolysis and promoted cell apoptosis and cell cycle arrest. Mechanically, circPTK2 functioned as the sponge for miR-582-3p to positively ALG3 expression in AML cells. Moreover, miR-582-3p inhibition ameliorated the impacts of circPTK2 knockdown on AML cell processes. MiR-582-3p overexpression regulated cell phenotypes by targeting ALG3., Conclusion: CircPTK2 contributed to AML cell malignant behaviors by modulation of miR-582-3p/ALG3 axis, which might provide a potential target for AML therapy.

The modeling of chimeric antigen receptor (CAR) T cell therapies has been mostly focused on immunodeficient models. However, there are many advantages in studying CAR-T cell biology in an immunocompetent setting. We generated a fully murine CAR targeting CD105 (endoglin), a component of the TGFβ receptor expressed on the surface of certain solid tumors and acute leukemias. CD105-targeted CAR-T cells can be grown from various murine backgrounds, tracked in vivo by congenic marks, and be activated by CD105 in isolation or expressed by tumor cells. CD105-targeted CAR-T cells were toxic at higher doses but proved safe in lower doses and modestly effective in treating wild-type B16 melanoma-bearing mice. CAR-T cells infiltrating the tumor expressed high levels of exhaustion markers and exhibited metabolic insufficiencies. We also generated a human CD105 CAR, which was efficacious in treating human melanoma and acute myeloid leukemia in vivo . Our work details a new murine model of CAR-T cell therapy that can be used from immunologists to further our understanding of CAR-T cell biology. We also set the foundation for further exploration of CD105 as a possible human CAR-T cell target., Competing Interests: G.M.D. has filed patent applications around the use of PGC-1α as a metabolic reprogramming agent in cellular therapies., (© 2022 The Author(s). Published with license by Taylor & Francis Group, LLC.)

Acute myeloid leukemia (AML) is a group of genetically complex and heterogeneous invasive hematological malignancies with a low 5-year overall survival rate of 30%, which highlights the urgent need for improved treatment measures. RNA-binding proteins (RBPs) regulate the abundance of isoforms of related proteins by regulating RNA splicing, translation, stability, and localization, thereby affecting cell differentiation and self-renewal. It is increasingly believed that RBPs are essential for normal hematopoiesis, and RBPs play a key role in hematological tumors, especially AML, by acting as oncogenes or tumor suppressors. In addition, targeting an RBP that is significantly related to AML can trigger the apoptosis of leukemic stem cells or promote the proliferation of stem and progenitor cells by modulating the expression of important pathway regulatory factors such as HOXA9, MYC, and CDKN1A. Accordingly, RBPs involved in normal myeloid differentiation and the occurrence of AML may represent promising therapeutic targets.

Circular RNAs (circRNAs) are crucial non-coding RNAs in the process of tumorigenesis. Nevertheless, the biological function of circ&#95;0004277 in acute myeloid leukemia (AML) is blurred. Microarray data of circRNAs were utilized to evaluate circRNAs' differential expression in AML. Quantitative real-time polymerase chain reaction (qRT-PCR) was executed to determine circ&#95;0004277 and microRNA-134-5p (miR-134-5p) expression levels. The growth, migration and invasion of AML cells were tested by the cell counting kit-8 and Transwell experiment. Dual-luciferase reporter gene experiment, RNA immunoprecipitation (RIP) experiment and RNA pull-down experiment were executed to determine the targeting relationship between circ&#95;0004277 and miR-134-5p. Western blot assay was used to detect single stranded DNA binding protein 2 (SSBP2) expression. We observed that circ&#95;0004277 was down-regulated in AML, while miR-134-5p was up-regulated. Functionally, circ&#95;0004277 overexpression or inhibition of miR-134-5p remarkably suppressed AML cell viability, migration and invasion. Furthermore, miR-134-5p served as a direct downstream target of circ&#95;0004277 and SSBP2 was identified as a target of miR-134-5p. Compensation experiments showed that miR-134-5p mimics abolished the biological function of circ&#95;0004277 on malignant phenotypes of AML cells. Collectively, circ&#95;0004277 impedes AML development by adsorbing miR-134-5p and up-regulating SSBP2.

Acute myeloid leukemia (AML) is an aggressive hematologic malignancy with a dismal prognosis. Immunotherapeutic approaches using single agent checkpoint inhibitors have thus far shown limited success. We hypothesized that successful adaptive anti-AML specific immune responses require additional modulation of innate immunity. DMXAA exposure resulted in modest apoptosis of C1498 AML cells with a subtle increase in PD-L1 expression and limited production of IL-6 and IFN-β. In contrast, DMXAA + anti-PD-1 ab, but not either agent alone, significantly decreased in vivo disease burden and prolonged overall survival in C1498 engrafted leukemic mice. Combination-treated mice demonstrated increased memory T-cells and mature dendritic cells, lower numbers of regulatory T-cells and evidence of leukemia apoptosis. Furthermore, these effects were associated with markedly increased serum levels of type I interferon (IFN) and IFN gamma. We demonstrate that combining an innate immune agonist with a checkpoint inhibitor synergistically improved anti-tumor activity in a preclinical AML model.

Introduction: The FMS-like tyrosine kinase 3 (FLT3) gene is mutated in one-third of patients with Acute Myeloid Leukemia (AML). Midostaurin, quizartinib, and gilteritinib have been approved in the last years for the treatment of AML, and more Tyrosine Kinase Inhibitors (TKIs) targeting FLT3 are being developed such as crenolanib., Areas Covered: In this systematic review, we will analyze the available clinical data on FLT3 inhibitors in development and describe the potential role that these FLT3-TKIs may play in the future management of FLT3-mutated (FLT3mut) AML., Expert Opinion: Although several aspects may challenge the use of FLT3 inhibitors in AML (resistance mechanisms, on- and off-target toxicities or drug-drug interactions), these drugs are generally well tolerated, particularly if we compare their safety profile with classical chemotherapy agents or even with newer immunotherapies, thus enabling their use in fit and unfit AML patients, alone or combined. As AML is a polyclonal disease and FLT3 mutations are a late leukemogenic event, combinations of these FLT3 inhibitors with other antileukemic agents (like venetoclax or hypomethylating agents) seem a necessary research pathway.

RAB27B is a member of Ras-like small GTPases that plays a role in endocytosis, exocytosis, and vesicle trafficking. We made an attempt to study the impacts of RAB27B on the proliferation and apoptosis of acute myeloid leukemia (AML) cells. The silencing of RAB27B was induced by siRNA for the detection of proliferation, cell cycle, and apoptosis, respectively by Cell Counting Kit-8 (CCK8), flow cytometry, and TUNEL. Related markers were also evaluated by Western blot analysis. The interaction between RAB27B and BDH2 was predicted by bioinformatics analysis and determined by immunoprecipitation. The gain of function of BDH2 was also detected by these functional assays. RAB27B exhibited high levels in AML cells, and RAB27B silencing led to reduced proliferation, increased cell cycle arrest and apoptosis levels. Then, the interaction between RAB27B and BDH2 was confirmed. Moreover, the effects of RAB27B inhibition on the proliferation, cell cycle arrest, and cell apoptosis were abolished after BDH2 overexpression. RAB27B inhibits proliferation and promotes apoptosis of leukemic cells by interacting with BDH2. Targeting RAB27B might be an effective method for the treatment of AML.

To investigate the effects of myeloid ecotropic viral integration site-1 (MEIS1) on the proliferation and apoptosis of acute myeloid leukemia (AML) cells and the anticancer effects of the drug, we screened Kasumi-6, KG-1, and Kasumi-1 cells using quantitative reverse transcription polymerase chain reaction. Kasumi-6 and Kasumi-1 cells were subjected to human antigen R (HuR)-mediated interference (IV). Hexokinase 2 (HK2) expression and phosphorylation of protein kinase B (p-AKT) and mammalian target of rapamycin (p-mTOR) were observed with Western blotting. Cell proliferation was assessed using Cell Counting Kit-8, apoptosis was examined using Hoechst 33,258 staining, and glucose uptake was detected with a colorimetric biochemical assay kit. We found that, among the three cell lines tested, MEIS1 expression was highest in Kasumi-1 cells, which were therefore selected for subsequent experiments. Kasumi-1 cells receiving IV showed significantly decreased proliferation (p < 0.05) and increased apoptosis compared to the control group. Compared with the controls, IV significantly increased the expression of HK2, p-AKT, p-mTOR, multidrug resistance-associated protein 1 and P-glycoprotein (P < 0.05), but decreased glucose uptake. Treatment with adriamycin, daunorubicin and imatinib resulted in a progressive increase in inhibition of cell proliferation, with the IV group showing the highest inhibition rate among the three groups (P < 0.05). Thus, inhibition of MEIS1 activity promoted apoptosis, inhibited the proliferation of Kasumi-1 and Kasumi-6 cells, and increaseed the anticancer effect of the drugs, suggesting that inhibition of MEIS1 may be a potential strategy for the treatment of AML.

Over 30-35% of patients down with AML are caused by mutations of FLT3-ITD and FLT3-TKD which keeps the protein activated while it activates other signaling proteins downstream that are involved in cell proliferation, differentiation, and survival. As drug targets, many inhibitors are already in clinical practice. Unfortunately, the average overall survival rate for patients on medication suffering from AML is 5 years despite the huge efforts in this field. To perform docking simulation and ADMET studies on selected phytochemicals against FLT3 protein receptor for drug discovery against FLT3 induced AML, molecular docking simulation was performed using human FLT3 protein target (PDB ID: 6JQR) and 313 phytochemicals with standard anticancer drugs (Sorafenib and Gilteritinib in addition to other anticancer drugs). The crystal structure of the protein was downloaded from the protein data bank and prepared using Biovia Discovery Studio. The chemical structures of the phytochemicals were downloaded from the NCBI PubChem database and prepared using Open Babel and VConf softwares. Molecular docking was performed using PyRx on Autodock Vina. The ADMET properties of the best performing compounds were calculated using SwissADME and pkCMS web servers. The results obtained showed that glabridin, ellipticine and derivatives (elliptinium and 9-methoxyellipticine), mezerein, ursolic acid, formononetin, cycloartocarpesin, hypericin, silymarin, and indirubin are the best performing compounds better than sorafenib and gilteritinib based on their binding affinities. The top-performing compounds which had better binding and ADMET properties than sorafenib and gilteritinib could serve as scaffolds or leads for new drug discovery against FLT3 induced AML.Communicated by Ramaswamy H. Sarma.

Acute myeloid leukemia (AML) was confirmed to be associated with hematopoietic insufficiency, as well as abnormal proliferation, differentiation or survival of myeloid progenitors. Multiple studies reported that microRNA-204 (miR-204) and Hepatocyte growth factor (HGF) played important roles in types of cancers. However, the potential molecular regulatory mechanism between miR-204 and HGF in AML remains to be further defined. Real-time PCR (RT-PCR) was adopted to detect the expression of miR-204 and HG. Relative protein levels were detected by western blot assay. The viability, cell cycle, apoptosis, migration, and invasion were analyzed by MTT, flow cytometry, and transwell assays. Moreover, the target relationship between miR-204 and HGF was predicted by MiRcode website and confirmed by luciferase reporter, RNA pull-down, and western blot assays. Our data suggested that miR-204 was downregulated in AML serum samples and cells. MiR-204 overexpression repressed cell proliferation, migration, invasion, and induced cell apoptosis in AML cells. HGF was upregulated in AML samples and cells, and HGF knockdown inhibited the malignancy of AML cells. In addition, HGF was directly targeted by miR-204. HGF overexpression reversed the effects of miR-204 mimic on AML cell proliferation, apoptosis, migration, and invasion. Besides, miR-204 regulated the c-Met signaling by targeting HGF, thereby regulating the downstream protein levels related to cell proliferation, apoptosis, migration, and invasion in AML cells. In conclusion, miR-204 could regulate AML progression through regulating the HGF/c-Met pathway.

In the present study, we determined the effects of the Src family kinase (SFK) inhibitor, Bosutinib, and the engineered loss of the Lyn SFK on all-trans retinoic acid-induced leukemic cell differentiation. Retinoic acid (RA) is an embryonic morphogen and dietary factor that demonstrates chemotherapeutic efficacy in inducing differentiation of a non-APL AML cell model, the HL-60 human myeloblastic (FAB-M2) leukemia cell line, via activation of a novel signalsome containing an ensemble of signaling molecules that drive differentiation. Bosutinib is an inhibitor of SFKs used to treat myeloid leukemias where prominent high expression of SFKs, in particular Lyn, has been observed. Using either Bosutinib or loss of Lyn expression due to shRNA promoted RA-induced phenotypic differentiation, G0 arrest, and respiratory burst (functional differentiation) of HL-60 cells. Signaling events putatively seminal to RA-induced differentiation, the expression of Fgr, Cbl, Slp-76 and Vav, and the phosphorylation of c-Raf (pS259), Vav (p-tyr), and Slp76 (p-tyr) were not inhibited by Bosutinib or loss of Lyn. Nor was RA-induced upregulation of p-tyr phosphorylation of p47phox, a member of the NADPH complex that produces ROS, a putative phosphorylation dependent signaling regulator. Surprisingly, Bosutinib still works in the absence of Lyn to enhance RA-induced differentiation and neither compromised RA-induced expression, nor phosphorylation of signaling molecules that drive differentiation. These findings suggested there is a novel, off-target, Lyn-independent effect of Bosutinib that is of therapeutic significance to differentiation therapy.

To study the regulation of miR-148a-3p on CDK6 and its mechanism in the progress of acute myeloid leukemia (AML), differential miRNAs were analyzed by bioinformatics, and the miR-148a-3p levels in AML cell lines were detected. Results showed that miR-148a-3p played a crucial role in AML, and the level was lower in AML cells, especially in J111 and KG-1a cells. In J111 and KG-1a cells, the up-regulation of miR-148a-3p mimics blocked the cell growth by arresting cell cycle at G2/M and enhancing cell apoptosis. Transwell and EMT markers detection indicated that miR-148a-3p reduced the cell migration and invasion. Afterward, through bioinformatics analysis, it showed that the CDK6 is one of the direct target genes of miR-148a-3p. DLR assay confirmed the target regulation. CDK6 overexpression reversed the effects of miR-148a-3p on AML cells. Collectively, miR-148a-3p inhibited the process of AML cells through disturbing the CDK-6 expression, implying that the trageting miR-148a-3p might be regarded as effective therapy of AML.

Spinster homolog 3 (SPNS3) belongs to the Spinster (SPNS) family which participates in sphingolipid transportation through the cell membrane. However, the functions of SPNS3 in acute myeloid leukemia (AML) are unknown. This study obtained SPNS3 from a gene set that was related to AML relapse and evaluate whether high SPNS3 expression induced apoptosis resistance in an AML cell line, which is consistent with the role of SPNS3 as a marker of poor prognosis in the clinic. Moreover, internal tandem duplication of FMS-like tyrosine kinase 3 (FLT3-ITD) mutation and the AC127521.1/ MIR-139/SPNS3 competing endogenous RNA axis were found to regulate SPNS3 expression. In addition, we noted that SPNS3 may play an important role in the Sphingosine-1-phosphate signal pathway that is involved in the maintenance of the AML microenvironment. These results highlight the anti-apoptosis effect of SPNS3 in AML, and the potential mechanism mediating this effect was explored through bioinformatics. Abbreviations: AML: acute myeloid leukemia; FLT3-ITD: internal tandem duplication of FMS-like tyrosine kinase 3; SPNS3: spinster homolog 3; SPNS1: spinster homolog 1; SPNS2: spinster homolog 2; GO: gene ontology; S1P: sphingosine-1-phosphate; ceRNA: competing endogenous RNA; dAML: acute myeloid leukemia at diagnosis; iAML: acute myeloid leukemia after induction chemotherapy; rAML: acute myeloid leukemia at relapse; DEGs: differentially expressed genes; BP: biological processes; CC: cellular components; MF: molecular functions; MRD: minimal residual disease; EFS: event-free survival; OS: overall survival; KEGG: Kyoto Encyclopedia of Genes and Genomes; SPHK: Sphingosine kinase.

MicroRNAs (miRNAs) play a very important role in the development of acute myeloid leukemia (AML). This study focuses on the effects of miR-9 on the regulation of AML cells and their related signaling pathways. We found that the expression of miR-9 was significantly decreased in four AML cell lines (THP-1, HL-60, TF-1 and KG-1) compared with the human normal bone marrow cells (HS-5). Moreover, miR-9 overexpression inhibited HL-60 cell proliferation ability, and promoted apoptosis. However, interfering with miR-9 expression promoted the proliferation of HL-6 cells and inhibited apoptosis. Western blotting results subsequently showed that overexpression of miR-9 could elevate the expression of MAT1, LATS1, and LATS2 in HL-60 cells, and inhibit the expression of YAP, while the interference with miR-9 had the opposite result. Taken together, miR-9 may act as a tumor suppressor by activating the Hippo/YAP signaling pathway of AML cells, which in this way supply ideas for the clinical remedy of AML patients.

Objectives: Reactive oxygen species (ROS) are under scrutiny as a participant in the pathophysiology of myelodysplastic syndrome (MDS) and the progression of MDS to acute myeloid leukemia (AML). Measurement of intracellular ROS (iROS) is particularly important since iROS is a direct indicator of cellular health and integrity. Methods: We developed a technique to measure standardize iROS (siROS) level in lymphocytes and bone marrow (BM) CD34 + hematopoietic progenitors using the fluorescent probe dichlorofluorescein (DCF). We then quantified the siROS in 38 consecutive BM specimens from 27 MDS patients over the course of 10 months. Disease outcome of these patients were also assessed. Results: High serum ferritin, high blast count and poor IPSS were associated with inferior survival and AML progression in this cohort. High blast MDS patients had lower siROS in their BM CD34+ cells than those of low blast patients, consistent with increased reliance on glycolysis and enhanced ROS defense in high blast MDS. We also observed narrower siROS distribution in the BM CD34+ cells of high blast patients, suggesting that loss of heterogeneity in ROS content accompanies the clonal evolution of MDS. Furthermore, we observed a strong correlation between CD34+ cells siROS and serum ferritin level in high blast patients. In one case, iron chelation therapy (ICT) resulted in parallel decreases in serum ferritin and CD34 + cells siROS. Conclusion: Our findings established the siROS profile in early hematopoietic cells of MDS patients and its relationship with blast count and iron overload.

All-trans retinoic acid (ATRA) is only clinically useful in acute promyelocytic leukemia (APL), but not other subtypes of acute myeloid leukemia (AML). In the present study, a clinically achievable concentration of trametinib, a highly selective inhibitor of MEK, enhanced ATRA-induced differentiation in AML cell lines, HL-60 and U937 as well as AML primary cells. Moreover, trametinib-ATRA (tra-ATRA) co-treatment restored ATRA sensitivity in ATRA-resistant AML cell line, HL-60Res. The protein level of STAT3 and the phosphorylation of Akt or JNK were enhanced with tra-ATRA treatment in HL-60, U937, and HL-60Res cells, respectively. Furthermore, tra-ATRA-induced differentiation in HL-60, U937, and HL-60Res cells was inhibited by STAT3, PI3K, and JNK inhibitors, respectively. Therefore, STAT3, Akt, and JNK signaling pathways were involved in tra-ATRA-induced differentiation in HL-60, U937, and HL-60Res cells, respectively. Taken together, our findings may provide novel therapeutic strategies for AML patients.

Objectives: Acute myeloid leukaemia (AML) is a haematopoietic malignancy with a dismal outcome. Consequently, risk stratification based on more effective prognostic biomarkers is crucial to make accurate therapy decisions. T cell receptor gamma alternative reading frame protein (TARP) has been reported in prostate and breast cancers, but its correlation with AML remains unclear., Methods: Differential expression of TARP mRNA in different AML subtypes was analysed using the UALCAN online platform. Its relationship with baseline clinical attributes, survival and efficacy were analysed based on three GSE1159, GSE425 and GSE6891 microarray datasets downloaded from Gene Expression Omnibus (GEO) and Oncomine databases. Quantitative real-time PCR was performed to determine mRNA levels of TARP in bone marrow mononuclear cells (BMMCs) isolated from AML patients., Results: TARP was significantly overexpressed in AML patients. In AML, relatively low TARP expression was associated with the CBFβ-MYH11 fusion gene. The proportion of FLT3 mutations was significantly higher in non-adolescent and young adult (non-AYA, >39 years of age) AML patients who had high TARP levels but not in AYA (15-39 years) patients. High expression of TARP was related to poor outcome by univariate analysis but not by multivariate analysis and unsatisfactory therapeutic effects, which could be overcome by haematopoietic stem cell transplantation (HSCT)., Conclusion: Our findings suggest that TARP might be a potential prognostic marker of AML and serve as a promising immunotherapeutic target.

Objectives: Previous study ( Br. J. Haematol. 2017; 176:498) reported that CD56 positive is associated with poor prognosis of patients with intermediate-risk acute myeloid leukemia (IR-AML). However, our data were inconsistent with the finding . Thus, in this study, we provided the different results to discuss., Methods: A total of 262 bone marrow transcriptomic data of IR-AML in the GSE12417-GPL96 and GSE71014-GPL-10558 from the Gene Expression Omnibus database (GEO) database, and 92 IR-AML patients from the cancer genome atlas (TCGA) database were obtained for prognostic analysis and validation., Results: Compared with low CD56 expression, IR-AML patients with high CD56 expression had a longer overall survival (OS) time and restricted mean survival time (RMST) and favorable OS rate in the GSE12417-GPL96 dataset. These results were confirmed in both GSE71014-GPL-10558 and TCGA datasets. Importantly, the inconsistency between our findings and the previous finding may be due to the following reasons: different detection methods, age stratification, countries, treatment options etc., Conclusions: The prognostic value of CD56 expression in IR-AML may need to be comprehensively evaluated based on different detection methods, age stratification, countries, treatment options, and other factors. If confirmed, CD56 may be a biomarker for further risk stratification for IR-AML patients.

As a new type of non-coding RNA, the role of circular RNA (circRNA) in various diseases and tumors has received considerable attention. Studies have shown that circRNAs play an important role in the progression of acute myeloid leukemia (AML) via different mechanisms. However, the specific underlying molecular mechanism of circRNAs in the proliferation of AML cells remians unclear. This study aimed to clarify the biological role and mechanism of circCRKL in AML. The results indicated low circCRKL expression in AML cell lines and samples. Moreover, the overexpression of circCRKL inhibited the proliferation and colony-forming ability of AML cells, while its silencing promoted them. In addition, bioinformatics tools and luciferase assays revealed that circCRKL could sponge miR-196a-5p and miR-196b-5p to promote the expression of p27. Furthermore, circCRKL inhibited AML cell proliferation via the miR-196a-5p/miR-196b-5p/p27 axis, suggesting a potential new target for AML therapy.

Acute myeloid leukemia (AML) represents a hematopoietic cancer with an invasive property. Chemoresistance blunts the therapeutic effect of chemotherapeutics in AML. Long noncoding RNAs (lncRNAs) have been implicated in chemotherapy resistance in AML. Transcriptome sequencing in the current study was applied to clarify the differentially expressed lncRNAs between peripheral blood mononuclear cells of AML and normal samples. The expression of special AT-rich sequence binding protein 1 antisense RNA 1 (SATB1-AS1) and 2'-5'-oligoadenylate synthetase 2 (OAS2) in AML patients was evaluated by qRT-PCR. The relationships among SATB1-AS1, microRNA-580 (miR-580) and OAS2 were investigated by dual-luciferase reporter assay. We observed that SATB1-AS1 and OAS2 were upregulated, while miR-580 was downregulated in AML patients. SATB1-AS1 depletion suppressed proliferation, and enhanced apoptosis and sensitivity of AML cells. Additionally, SATB1-AS1 promoted the expression of OAS2 by acting as a molecular sponge of miR-580 in AML. miR-580 downregulation, OAS2 overexpression and a selective glycogen synthase kinase (GSK)-3β inhibitor AR-A014418 abolished the effects of SATB1-AS1 deletion on the chemosensitivity of AML cells. In conclusion, SATB1-AS1 knockdown promotes the sensitivity of AML cells by upregulating miR-580 and downregulating OAS2 through the GSK3β/β-catenin pathway, providing new insights into the function of SATB1-AS1 as a miRNA sponge in AML.

There has been an explosion of knowledge about the role of metabolism and the mitochondria in acute myeloid leukemia (AML). We have also recently seen several waves of novel therapies change the treatment landscape for AML, such as the selective B-cell lymphoma 2 (BCL-2) inhibitor venetoclax. In this new context, we review the rapidly advancing literature on the role of metabolism and the mitochondria in AML pathogenesis, and how these are interwoven with the mechanisms of action for novel therapeutics in AML. We also review the role of oxidative phosphorylation (OxPhos) in maintaining leukemia stem cells (LSCs), how recurrent genomic alterations in AML alter downstream metabolism, and focus on how the BCL-2 pathway and the mitochondria are inextricably linked in AML. Thus, we provide an overview of the mitochondria and metabolism in the context of our new therapeutic world for AML and outline how targeting these vulnerabilities may produce novel therapeutic strategies.

WT1 has been reported to function as an oncogene and a tumor suppressor in acute myeloid leukemia (AML). The molecular mechanisms have not yet been fully elucidated. Here, we report that p53, served as a tumor suppressor, plays a critical role in regulating the function of WT1 in AML. For details, we performed a meta-analysis on 1131 AML cases, showing that WT1 gene mutation and TP53 gene exhibited a mutually exclusive predisposition in AML. p53 can be recruited to the promoter region of WT1's target genes to modulate their expression by physically interacting with WT1. The AML-derived p53 mutation (p53 R248Q ) can disrupt the interaction between WT1 and p53, resulting in the loss of modulation of WT1's target genes. Furthermore, wild-type p53 maintained the anti-proliferation activity of WT1 in AML cells. In contrast, WT1 promoted AML cell proliferation in the absence of p53 (or mutated p53). In conclusion, we demonstrated a novel explanation of the controversial function of WT1 in AML. These results provided a mechanism by which WT1 inhibited AML cell proliferation in a p53-dependent manner.

The aim of this study was to establish the therapeutic relevance of the CD33 D2 isoform by developing novel antibodies targeting the IgC domain of CD33. Two novel IgC-targeting antibodies, HL2541 and 5C11-2, were developed, and CD33 isoforms were assessed using multiple assays in cells overexpressing either CD33 FL or CD33 D2 isoforms, unmodified acute myeloid leukemia (AML) cell lines and primary AML specimens representing different genotypes for the CD33 splicing single nucleotide polymorphism. CD33 D2 was recognized on cells overexpressing CD33 D2 and unmodified AML cell lines; however, minimal/no cell surface detection of CD33 D2 was observed in primary AML specimens. Both isoforms were detected intracellularly using novel antibodies. Minimal cell surface expression of CD33 D2 on primary AML/progenitor cells warrants further studies on anti-CD33 D2 immunotherapeutics.

Introduction: A variety of molecular-targeted drugs have been widely used in hematological malignancies and have shown great advances. Nevertheless, as the use of drugs in clinical practice increases, the problem of relapse or of the disease being refractory to treatment is becoming apparent. This problem is closely related to the C-X-C chemokine receptor 4 (CXCR4)., Areas Covered: This review focuses mainly on the effect of CXCR4 on molecular-targeted drug resistance in hematological malignancies as well as the clinical efficacy of CXCR4 antagonists combined with molecular-targeted drugs. Relevant literatures published between 2006 and 2020 were searched using PubMed/Medline for this review., Expert Opinion: Monoclonal antibodies and non-antibody molecular-targeted drugs provide new therapeutic approaches for B-lineage malignancies and leukemia, but the clinical activity of these drugs is affected by CXCR4. In general, high CXCR4 expression or mutation inhibits the effects of molecular-targeted drugs, but there are exceptions, and in studies of proteasome inhibitors bortezomib (Bz) in multiple myeloma (MM), low CXCR4 expression or loss of CXCR4 was associated with Bz resistance (BzR) and poor treatment outcomes. Given that CXCR4 is a critical mediator of molecular-targeted drug resistance, numerous studies have combined molecular-targeted drugs with CXCR4 antagonists, which synergistically enhance the anti-proliferative/pro-apoptotic effect of molecular-targeted drugs.

ABSTRACT Objectives: Long non-coding RNA (lncRNA) small nucleolar RNA host gene 4 (SNHG4) is a characterized oncogenic lncRNA in osteosarcoma. The analysis of the TCGA dataset suggested the downregulation of SNHG4 in acute myeloid leukemia (AML), indicating its possible involvement in this disease. Therefore, this study was performed to analyze the interaction between SNHG4 and miR-10a in AML. Methods: We included 60 patients with AML and 60 healthy participants. Transient transfections, luciferase activity assay, RT-qPCR, CCK-8, and Western blot were used to carry out the research. Results: In this study, we found that SNHG4 was downregulated in AML patients compared to healthy participants. SNHG4 and miR-10a can interact with each other. However, overexpression of SNHG4 and miR-10a failed to affect the expression of each other. Instead, SNHG4 overexpression led to upregulated PTEN, a downstream target of miR-10a. Cell proliferation analysis showed that SNHG4 and PTEN overexpression led to decreased proliferation rates of AML cells and attenuated the enhancing effects of miR-10a on cell proliferation. Conclusion: In conclusion, SNHG4 may regulate miR-10a/PTEN to inhibit the proliferation of AML cells.

Translocations of the KMT2A (MLL) gene define a biologically distinct and clinically aggressive subtype of acute myeloid leukaemia (AML), marked by a characteristic gene expression profile and few cooperating mutations. Although dysregulation of the epigenetic landscape in this leukaemia is particularly interesting given the low mutation frequency, its comprehensive analysis using whole genome bisulphite sequencing (WGBS) has not been previously performed. Here we investigated epigenetic dysregulation in nine MLL-rearranged (MLL-r) AML samples by comparing them to six normal myeloid controls, using a computational method that encapsulates mean DNA methylation measurements along with analyses of methylation stochasticity. We discovered a dramatically altered epigenetic profile in MLL-r AML, associated with genome-wide hypomethylation and a markedly increased DNA methylation entropy reflecting an increasingly disordered epigenome. Methylation discordance mapped to key genes and regulatory elements that included bivalent promoters and active enhancers. Genes associated with significant changes in methylation stochasticity recapitulated known MLL-r AML expression signatures, suggesting a role for the altered epigenetic landscape in the transcriptional programme initiated by MLL translocations. Accordingly, we established statistically significant associations between discordances in methylation stochasticity and gene expression in MLL-r AML, thus providing a link between the altered epigenetic landscape and the phenotype.