Targeted Therapy Development in Acute Myeloid Leukemia

Contemporary understanding of myeloid-derived suppressor cells in the acute myeloid leukemia (AML) and myelodysplastic syndrome (MDS) tumor microenvironment

INTRODUCTION

Myeloid-derived suppressor cells (MDSCs) are a key immunosuppressive component in the tumor microenvironment, contributing to immune evasion and disease progression in acute myeloid leukemia (AML) and myelodysplastic syndromes (MDS).

AREAS COVERED

We searched PubMed for literature that evaluated the effect of MDSCs in myeloid diseases. MDSCs impact outcomes by facilitating leukemic stem cell survival, impairing immune checkpoint efficacy, and modulating the bone marrow niche. While these immunosuppressive properties can mitigate graft-versus-host disease post-transplantation, sustained MDSC-mediated immunosuppression can also increase the risk of leukemia relapse.We review MDSC development and function, including metabolic reprogramming, epigenetic modifications, and cytokine-mediated pathways. Therapeutic strategies targeting MDSCs, such as depletion, functional reprogramming, and inhibition of key metabolic and immune pathways, show promising data in preclinical models. However, clinical translation remains hindered by challenges in MDSC quantification and standardization of functional assays. This review underscores the potential of combining MDSC-targeted therapies with conventional and novel treatments to improve patient outcomes in AML and MDS.

EXPERT OPINION

Future studies should focus on standardizing MDSC assessment, elucidate their dynamic roles in therapy, and optimize combination approaches for clinical application.

DDB1 engagement defines the selectivity of S656 analogs for cyclin K degradation over CDK inhibition

In efforts to identify additional therapeutic targets for Acute Myeloid Leukemia (AML), we performed a high-throughput screen that includes 56 primary specimens tested with 10,000 structurally diverse small molecules. One specific hit, called S656 acts as a molecular glue degrader (MGD), that mediates the CRL4-dependent proteolysis of cyclin K. Structurally, S656 features a moiety that binds to the ATP binding site of cyclin-dependent kinases (CDKs), allowing the recruitment of the CDK12-cyclin K complex, along with a binding site for DDB1 bridging the CRL4 complex. Structure activity relationship studies reveal that minimal modifications to the dimethylaniline moiety of S656 improve its cyclin K MGD function over CDK inhibition by promoting DDB1 engagement. This includes full occupation of the DDB1 pocket, preferably with hydrophobic terminal groups, and cation-π interaction with Arg928. Additionally, we demonstrate that despite structural diversity, cyclin K degraders exhibit similar functional activity in AML which is distinct from direct CDK12 inhibition.

Extracellular vesicles in acute myeloid leukemia: The role in disease pathogenesis, potential biomarker, and application in clinical settings

Acute myeloid leukemia (AML), the most prevalent type of blood cancer, is initiated in the bone marrow and eventually migrates into the blood. It accounts for a 5-year overall survival rate of 29.8 %. AML results from the formation of immature white blood cells, also called AML blasts, from hematopoietic stem cells which eventually give rise to abnormal white blood cells, termed AML cells. The interaction of AML cells with their microenvironment appears to be significantly important in the pathogenesis of AML. A growing body of evidence identifies extracellular vesicles (EVs) to be a key component in intercellular communication via the transfer of biomolecules, such as DNA, RNAs, proteins, non-coding RNAs, lipids, metabolites etc. Although the role of EVs in various solid tumors is well-established, EVs' contribution to the pathogenesis of blood cancer, such as AML remains ill-defined. The present review highlights how EVs promote the progression of AML by influencing leukemogenesis, survival, angiogenesis, chemotherapeutic resistance, and immune evasion. A significant number of EVs are found in the biofluids of AML patients which are shown to carry signature cargo molecules, thereby rendering the EVs as predictive biomarkers for AML pathogenesis. EV-based clinical trials are mentioned in the later part of the review. Finally, EV-based therapeutics and their limitations are also briefly discussed in the context of AML.

piRNAs in leukemogenesis: Mechanisms, biomarkers, and therapeutic implications

The small, non-coding RNAs known as piwi-interacting RNAs (piRNAs) serve essential roles in gene regulation by silencing transposable elements and protecting oncogenes and tumour suppressors. The production of piRNA bioactive forms uses precursor mRNAs, which team with Piwi proteins to support genome maintenance. Accurate leukaemia regulation requires piRNAs because abnormalities in these regulatory elements contribute to disease development and drug resistance progression. Their utility in disease detection appears promising through their distinct pattern expression across different leukaemia subtypes. These piRNA markers promise to enhance early detection of diseases and provide treatment effectiveness and outcome information. Lesions examined by microarrays qRT-PCR and high-throughput sequencing provide professionals with essential tools for studying piRNA profiles and tracking their activities in leukaemia treatment. PiRNAs establish interactions with microRNAs and long non-coding RNAs through complex regulatory networks, contributing to leukaemia development. The therapeutic applications of piRNAs in leukaemia treatment have proven promising, yet additional research is necessary to understand their specific functions and improve standardized detection capability. The field requires future investigations dedicated to designing piRNA-based diagnostic instruments, researching piRNA-derived drug resistance prevention strategies, and optimizing individualized treatment plans for leukaemia patients.

A common ground: an in silico assessment of the sources of intrinsic ex vivo resistance to venetoclax in acute myeloid leukemia

Venetoclax is a promising alternative for patients with acute myeloid leukemia who are considered unfit for conventional chemotherapy; however, its employment still faces challenges mostly related to drug resistance. Here, we provide further biological mechanisms underlying the previously described and potentially novel intrinsic sources of poor response to venetoclax departing from ex vivo response data. Acute myeloid leukemia data including FLT3 mutation status, gene expression data, and ex vivo response data were extracted from the publicly available BeatAML 1.0 study database and aided sample categorization that supported differential gene expression analysis that, in turn, supported gene set enrichment analysis. CIBERSORTx-based bulk RNA sequencing deconvolution of BeatAML 1.0 data allowed us to categorize samples according to their cell type content. We observed that inflammation-related gene sets, such as cytokines and inflammatory response, NLRP3 inflammasome activation, and activation of adaptive immune response, were concordantly positively enriched across all the conditions reported to be associated with poor ex vivo venetoclax response, whereas samples from good ex vivo responders' mostly enriched gene sets related to mitochondrial activity, and early myeloid progenitor cell molecular programs. Besides the alternative reliance on BCL2A1, we highlight inflammation as a common element present across multiple sources of venetoclax ex vivo response modulation in acute myeloid leukemia samples. Hence, a potential key modulator for venetoclax response.

Glycolysis-Driven Prognostic Model for Acute Myeloid Leukemia: Insights into the Immune Landscape and Drug Sensitivity

Background: Acute myeloid leukemia (AML), a malignant blood disease, is caused by the excessive growth of undifferentiated myeloid cells, which disrupt normal hematopoiesis and may invade several organs. Given the high heterogeneity in prognosis, identifying stable prognostic biomarkers is crucial for improved risk stratification and personalized treatment strategies. Although glycolysis has been extensively studied in cancer, its prognostic significance in AML remains unclear. Methods: Glycolysis-related prognostic genes were identified by differential expression profiles. We modeled prognostic risk by least absolute shrinkage and selection operator (LASSO) regression and validated it by Kaplan-Meier (KM) survival analysis, receiver operating characteristic (ROC) curves, and independent datasets (BeatAML2.0, GSE37642, GSE71014). Mechanisms were further explored through immune microenvironment analysis and drug sensitivity scores. Results: Differential expression and survival correlation analysis across the genes associated with glycolysis revealed multiple glycolytic genes associated with the outcomes of AML. We constructed a seven-gene prognostic model (G6PD, TFF3, GALM, SOD1, NT5E, CTH, FUT8). Kaplan-Meier analysis demonstrated significantly reduced survival in high-risk patients (hazard ratio (HR) = 3.4, p < 0.01). The model predicted the 1-, 3-, and 5-year survival outcomes, achieving area under the curve (AUC) values greater than 0.8. Immune profiling indicated distinct cellular compositions between risk groups: high-risk patients exhibited elevated monocytes and neutrophils but reduced Th1 cell infiltration. Drug sensitivity analysis showed that high-risk patients exhibited resistance to crizotinib and lapatinib but were more sensitive to motesanib. Conclusions: We established a novel glycolysis-related gene signature for AML prognosis, enabling effective risk classification. Combined with immune microenvironment analysis and drug sensitivity analysis, we screened metabolic characteristics and identified an immune signature to provide deeper insight into AML. Our findings may assist in identifying new therapeutic targets and more effective personalized treatment regimes.

Azacitidine and venetoclax with or without pevonedistat in patients with newly diagnosed acute myeloid leukemia

This phase 2 study investigated pevonedistat + azacitidine + venetoclax (n = 83) versus azacitidine + venetoclax (n = 81) in patients with newly diagnosed acute myeloid leukemia (AML) ineligible for intensive chemotherapy. The study was stopped early following negative results from PANTHER, which evaluated pevonedistat in higher-risk myelodysplastic syndromes/chronic myelomonocytic leukemia or low-blast AML. Outcomes were analyzed up to the datacut. For pevonedistat + azacitidine + venetoclax versus azacitidine + venetoclax, the median follow-up was 8.44 versus 7.95 months; the complete remission (CR) rate was 45% versus 49%; composite CR (CCR; CR+CR with incomplete blood count recovery) was 77% versus 72%. There were no differences in event-free survival (primary endpoint; hazard ratio [HR]: 0.99; 95% confidence interval [CI]: 0.61-1.60; p = 0.477) or overall survival (HR: 1.42; 95% CI: 0.82-2.49; p = 0.896). In exploratory analyses in IDH-mutated AML, CCR rates were higher with pevonedistat + azacitidine + venetoclax versus azacitidine + venetoclax. Safety was similar between treatment arms. Efficacy/safety with azacitidine + venetoclax was consistent with the phase 3 VIALE-A study.

TRIAL REGISTRATION

NCT04266795.

Diagnostic and Therapeutic Implications of the SUMOylation Pathway in Acute Myeloid Leukemia

Epigenetics encompasses heritable and stable changes in gene expression caused by external chromosomal modifications, without altering the underlying DNA sequence. Epigenetic modifications, established during early development and maintained through successive cell divisions, play a critical role in regulating gene expression. Post-translational modifications (PTMs) are a key aspect of epigenetics and are essential for modulating protein functionality, as well as regulatory cellular processes, including proliferation, differentiation, metabolic pathways, and tumorigenic events. Among these, the small ubiquitin-related modifier (SUMOylation) system is a reversible PTM mechanism that alters target protein interaction surfaces through covalent binding to lysine residues, thereby influencing protein structure and function. Acute myeloid leukemia (AML) is a highly aggressive malignancy characterized by the clonal expansion of primitive hematopoietic stem cells of the myeloid lineage in the bone marrow. Despite recent advancements in therapeutic strategies and an improved understanding of leukemogenic pathways, patient outcomes remain poor, particularly in elderly populations. Consequently, efforts have focused on developing novel agents, including co-targeting specific mutations or integrating targeted therapies into combinatorial chemotherapeutic regimens. Emerging evidence suggests that SUMOylation plays a significant role in AML pathogenesis and treatment response, representing a promising therapeutic target for advanced disease cases. This review provides a brief analysis of the functional role of the SUMOylation system in AML and highlights its potential as a therapeutic target. We also discuss current knowledge gaps and propose directions for future research to advance precision medicine approaches for AML treatment.

Advances in DNA/RNA Sequencing and Their Applications in Acute Myeloid Leukemia (AML)

Acute myeloid leukemia (AML) is an aggressive malignancy that poses significant challenges due to high rates of relapse and resistance to treatment, particularly in older populations. While therapeutic advances have been made, survival outcomes remain suboptimal. The evolution of DNA and RNA sequencing technologies, including whole-genome sequencing (WGS), whole-exome sequencing (WES), and RNA sequencing (RNA-Seq), has significantly enhanced our understanding of AML at the molecular level. These technologies have led to the discovery of driver mutations and transcriptomic alterations critical for improving diagnosis, prognosis, and personalized therapy development. Furthermore, single-cell RNA sequencing (scRNA-Seq) has uncovered rare subpopulations of leukemia stem cells (LSCs) contributing to disease progression and relapse. However, widespread clinical integration of these tools remains limited by costs, data complexity, and ethical challenges. This review explores recent advancements in DNA/RNA sequencing in AML and highlights both the potential and limitations of these techniques in clinical practice.

The Impact of Gilteritinib on Overall Survival of Adult Patients with FLT3 Positive Acute Myeloid Leukemia: A Systematic Review

BACKGROUND

Gilteritinib, an effective and selective inhibitor of the FLT3 gene, was developed to address the challenges posed by relapsed or refractory acute myeloid leukemia (AML) patients who often encounter limited treatment options and poor prognoses with salvage chemotherapy.

AIM

This systematic review aims to explore the progression of interventional research and consolidate existing evidence on the clinical effectiveness of gilteritinib as a monotherapy or combination therapy in improving overall survival among adults experiencing a recurrence or resistance to treatment for FLT3-positive AML patients.

METHODS

A comprehensive search strategy, utilizing Medical Subject Headings (MeSH) and non-MeSH terms was conducted across Pubmed, EMBASE, Cochrane, and Web of Science databases. We primarily focused on the clinical trial and retrospective studies on gilteritinib as an intervention for relapsed/refractory AML patients.

RESULTS

According to our predefined criteria for inclusion and exclusion, we identified 3 published clinical trials and 5 retrospective studies focused on the overall response of gilteritinib on refractory or relapsed AML adult patients published between January 1, 2018, and March 25, 2024. Clinical trial studies demonstrated superior survival outcomes than salvage chemotherapy in the FLT3-positive AML population particularly showing higher efficacy in combination therapy with Azacitidine. Retrospective studies from clinical trials revealed improved clinical outcomes in AML sub-populations.

CONCLUSION

Gilteritinib exhibited promising outcomes by targeting FLT3 receptors, offering a new treatment approach, and revealing improved overall survival compared to salvage chemotherapy in the difficult-to-treat patient population.

Potent, Selective, and Orally Bioavailable Quinazoline-Based STK17A/B Dual Inhibitors

STK17A is a novel uncharacterized member of the death-associated protein family of serine and threonine kinases. Overexpression of STK17A is observed in many cancers. We identified a lead compound that is based on a quinazoline core. Optimizations of the lead compound led to the discovery of potent and selective STK17A/B inhibitors with drug-like properties and oral bioavailability. Compound 9 had an STK17A inhibitory IC50 of 23 nM. Based on profiling studies against two wild-type kinase panels (375 and 398 kinases, respectively), compound 9 had strong inhibition of both STK17A and STK17B but moderate off-target inhibition only for AAK1, MYLK4, and NEK3/5. In addition, compound 9 had good oral bioavailability, paving the way for in vivo studies against various cancers.

Small molecule anticancer drugs approved during 2021-2022: Synthesis and clinical applications

Drugs have structural homology across similar biological targets. Small molecule drugs have the efficacy to target specific molecular targets within the cancer cells with enhanced cell membrane permeability, oral administration, selectivity, and specific affinity. The objective of this review is to highlight the clinical importance and synthetic routes of new small molecule oncology drugs approved by the FDA during the period 2021-2022. These marketed drugs are listed based on the month and year of approval in chronological order. We believed that an in-depth insight into the synthetic approaches for the construction of these chemical entities would enhance the ability to develop new drugs more efficiently.

Venetoclax Combination Treatment of Acute Myeloid Leukemia in Adolescents and Young Adult Patients

Over the past two decades, the prognosis in adolescents and young adults (AYAs) diagnosed with acute myeloid leukemia (AML) has significantly improved. The standard intensive cytotoxic treatment approach for AYAs with AML, consisting of induction chemotherapy with anthracycline/cytarabine combination followed by consolidation chemotherapy or stem cell transplantation, has lately been shifting toward novel targeted therapies, mostly in the fields of clinical trials. One of the most recent advances in treating AML is the combination of the B-cell lymphoma 2 (Bcl-2) inhibitor venetoclax with hypomethylating agents, which has been studied in elderly populations and was approved by the Food and Drug Administration (FDA) for patients over 75 years of age or patients excluded from intensive chemotherapy induction schemas due to comorbidities. Regarding the AYA population, venetoclax combination therapy could be a therapeutic option for patients with refractory/relapsed (R/R) AML, although data from real-world studies are currently limited. Venetoclax is frequently used by AYAs diagnosed with advanced hematologic malignancies, mainly acute lymphoblastic leukemia and myelodysplastic syndromes, as a salvage therapeutic option with considerable efficacy and safety. Herein, we aim to summarize the evidence obtained from clinical trials and observational studies on venetoclax use in AYAs with AML. Based on the available evidence, venetoclax is a safe and effective therapeutic option for R/R AML AYA patients. However, further research in larger cohorts is needed to confirm these data, establishing the benefits of a venetoclax-based regimen for this special population.

Pro-Inflammatory Activation Suppresses TRAIL-induced Apoptosis of Acute Myeloid Leukemia Cells

Tumor necrosis factor-related apoptosis-inducing ligand (TRAIL/Apo2L) is a promising agent for treatment of AML due to its specific apoptosis-inducing effect on tumor cells but not normal cells. However, emergence of resistance to TRAIL in the AML cells limits its potential as an antileukemic agent. Previously, we revealed increase in the resistance of the human AML THP-1 cells to the TRAIL-induced death during their LPS-dependent proinflammatory activation and in the in vitro model of LPS-independent proinflammatory activation - in a long-term high-density cell culture. In this study, we investigated mechanisms of this phenomenon using Western blot analysis, caspase 3 enzymatic activity analysis, quantitative reverse transcription-PCR, and flow cytometry. The results showed that the increased resistance to the TRAIL-induced cell death of AML THP-1 cells during their pro-inflammatory activation is associated with the decrease in the surface expression of the proapoptotic receptors TRAIL-R1/DR4 and TRAIL-R2/DR5, as well as with the increased content of members of the IAPs family - Livin and cIAP2. The results of this article open up new insights into the role of inflammation in formation of the resistance of AML cells to the action of mediators of antitumor immunity, in particular TRAIL.

Multiple machine-learning tools identifying prognostic biomarkers for acute Myeloid Leukemia

BACKGROUND

Acute Myeloid Leukemia (AML) generally has a relatively low survival rate after treatment. There is an urgent need to find new biomarkers that may improve the survival prognosis of patients. Machine-learning tools are more and more widely used in the screening of biomarkers.

METHODS

Least Absolute Shrinkage and Selection Operator (LASSO), Support Vector Machine-Recursive Feature Elimination (SVM-RFE), Random Forest (RF), eXtreme Gradient Boosting (XGBoost), lrFuncs, IdaProfile, caretFuncs, and nbFuncs models were used to screen key genes closely associated with AML. Then, based on the Cancer Genome Atlas (TCGA), pan-cancer analysis was performed to determine the correlation between important genes and AML or other cancers. Finally, the diagnostic value of important genes for AML was verified in different data sets.

RESULTS

The survival analysis results of the training set showed 26 genes with survival differences. After the intersection of the results of each machine learning method, DNM1, MEIS1, and SUSD3 were selected as key genes for subsequent analysis. The results of the pan-cancer analysis showed that MEIS1 and DNM1 were significantly highly expressed in AML; MEIS1 and SUSD3 are potential risk factors for the prognosis of AML, and DNM1 is a potential protective factor. Three key genes were significantly associated with AML immune subtypes and multiple immune checkpoints in AML. The results of the verification analysis show that DNM1, MEIS1, and SUSD3 have potential diagnostic value for AML.

CONCLUSION

Multiple machine learning methods identified DNM1, MEIS1, and SUSD3 can be regarded as prognostic biomarkers for AML.

Clinical Utility and Reimbursement of Next-Generation Sequencing-Based Testing for Myeloid Malignancies

Next-generation sequencing is becoming increasingly important for the diagnosis, risk stratification, and management of patients with established or suspected myeloid malignancies. These tests are being incorporated into clinical practice guidelines and many genetic alterations now constitute disease classification criteria. However, the reimbursement for these tests is uncertain. This study analyzed the clinical impact, ordering practices, prior authorization, and reimbursement outcomes of 505 samples from 477 patients sequenced with a 50-gene myeloid next-generation sequencing panel or a 15-gene myeloproliferative neoplasm subpanel. Overall, 98% (496 of 505) of tests provided clinically useful data. Eighty-nine percent of test results, including negative findings, informed or clarified potential diagnoses, 94% of results informed potential prognoses, and 19% of tests identified a potential therapeutic target. Sequencing results helped risk-stratify patients whose bone marrow biopsy specimens were inconclusive for dysplasia, monitor genetic evolution associated with disease progression, and delineate patients with mutation-defined diagnoses. Despite the clinical value, prior authorization from commercial payors or managed government payors was approved for less than half (45%) of requests. Only 51% of all cases were reimbursed, with lack of medical necessity frequently cited as a reason for denial. This study demonstrates the existence of a substantial gap between clinical utility and payor policies on test reimbursement.

AML under the Scope: Current Strategies and Treatment Involving FLT3 Inhibitors and Venetoclax-Based Regimens

Acute myeloid leukemia (AML) is a disease that mainly affects elderly patients who are more often unfit for intensive chemotherapy (median age of diagnosis is 68). The regimens, including venetoclax, a highly specific BCL-2 (B-cell lymphoma-2) inhibitor, are a common alternative because of their safer profile and fewer side effects. However, the resistance phenomenon of leukemic cells necessitates the search for drugs that would help to overcome the resistance and improve treatment outcomes. One of the resistance mechanisms takes place through the upregulation of MCL-1 and BCL-XL, preventing BAX/BAK-driven MOMP (mitochondrial outer membrane permeabilization), thus stopping the apoptosis process. Possible partners for BCL-2 inhibitors may include inhibitors from the FLT3i (FMS-like tyrosine kinase-3 inhibitor) group. They resensitize cancer cells through the downregulation of MCL-1 expression in the FLT3 mutated cells, resulting in the stronger efficacy of BCL-2 inhibitors. Also, they provide an additional pathway for targeting the clonal cell. Both preclinical and clinical data suggest that the combination might show a synergistic effect and improve patients' outcomes. The aim of this review is to determine whether the combination of venetoclax and FLT3 inhibitors can impact the therapeutic approaches and what other agents they can be combined with.

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.

Expression analysis, clinical significance and potential function of PLXNB2 in acute myeloid leukaemia

BACKGROUND

The overall survival (OS) rate of adult patients suffering from acute myeloid leukaemia (AML) remains unsatisfactory at less than 40%. Current risk stratification systems fail to provide accurate guidelines for precise treatment. Novel biomarkers for predicting prognosis are urgently needed. Plexin B2 (PLXNB2), a functional receptor of angiogenin (ANG), has been found to be aberrantly expressed in multitudinous tumours. We detected overexpression of PLXNB2 mRNA in AML via transcriptome microarray analysis. This study aims to explore the potential role of PLXNB2 as a biomarker of prognosis and a prospective target of AML.

METHODS

qRT‒PCR was conducted to verify the expression of PLXNB2 mRNA in bone marrow mononuclear cells from AML patients. Immunohistochemical and immunofluorescence staining were performed and confirmed increased expression of PLXNB2 protein in AML bone marrow tissues. Data on PLXNB2 expression, prognosis and clinical features were accessed from multiple bioinformatic databases, including The Cancer Genome Atlas (TCGA). Genes coexpressed and correlated with PLXNB2 were identified and analysed in the TCGA AML cohort. Metascape was applied for functional and pathway enrichment analysis of genes related to PLXNB2. Small molecular agents and traditional Chinese medicines potentially targeting genes related to PLXNB2 were screened via the Connectivity Map, TCMSP and HIT databases.

RESULTS

PLXNB2 mRNA and protein levels are higher in AML samples than in normal controls. Overexpression of PLXNB2 is associated with worse OS in AML. Patients with high PLXNB2 expression might benefit more from haematopoietic stem cell transplantation (HSCT) (indicated by prolonged OS) than those with only chemotherapy treatment. Differentially expressed genes between the high and low PLXNB2 expression groups were overlapped with PLXNB2-coexpressed genes, and genes that overlapped were enriched in immune functions, endothelial cell regulation and cell interaction gene sets, indicating the potential function of PLXNB2 in AML. A total of 36 hub genes were identified from the differentially expressed genes, and MRC1, IL10, CD163 and CCL22 had significant prognostic value for AML. Analysis of the connectivity map and traditional agents revealed that honokiol, morphines, triptolide and paeoniflorin could be potential treatment regimens.

CONCLUSIONS

The overexpression of PLXNB2 is an adverse prognostic factor in adult AML patients and could be used as a potential biomarker. PLXNB2 might exert an oncogenic role by modulating immune functions, endothelial cell functions and cell interactions. AML patients with high PLXNB2 expression could benefit more from HSCT.

LC-MS/MS method for the quantitation of decitabine and venetoclax in rat plasma after SPE: Application to pharmacokinetic study

This study developed a novel, sensitive and selective LC-MS/MS method for the concurrent determination of DCB and VTX in rat plasma using encorafenib as internal standard (IS). To identify DCB, VTX, and IS, the positive multiple reaction monitoring (MRM) mode was used. Chromatographic separation was carried out using a reversed-phase Agilent Eclipse plus C18 column (100 mm × 2.1 mm, 3.5 µm) and an isocratic mobile phase made up of water with 0.1% formic acid and acetonitrile (50:50, v/v, pH 3.2) at a flow rate of 0.30 mL/min for 3.0 min. Prior to analysis, the DCB and VTX with the IS were extracted from plasma using the solid-phase extraction (SPE) method. High recovery rates for DCB, VTX and IS were achieved using the C18 cartridge without interference from plasma endogenous. The developed method was validated as per the FDA guidelines over a linear concentration range in rat plasma from 5-3000 and 5-1000 ng/mL for DCB and VTX, respectively with r2 ≥ 0.998. For both drugs, the lower limits of detection (LLOD) were 2.0 ng/mL. After the HLOQ sample was injected, less than 20% of the LLOQ of DCB, VTX, and less than 5% of the IS carry-over in the blank sample was attained. The overall recoveries of DCB and VTX from rat plasma were in the range of 90.68-97.56%, and the mean RSD of accuracy and precision results was ≤6.84%. For the first time, the newly developed approach was effectively used in a pharmacokinetic study on the simultaneous oral administration of DCB and VTX in rats that received 15.0 mg/kg of DCB and 100.0 mg/kg of VTX.

Effective Prognostic Model for Therapy Response Prediction in Acute Myeloid Leukemia Patients

Acute myeloid leukemia (AML) is a hematopoietic disorder characterized by the malignant transformation of bone marrow-derived myeloid progenitor cells with extremely short survival. To select the optimal treatment options and predict the response to therapy, the stratification of AML patients into risk groups based on genetic factors along with clinical characteristics is carried out. Despite this thorough approach, the therapy response and disease outcome for a particular patient with AML depends on several patient- and tumor-associated factors. Among these, tumor cell resistance to chemotherapeutic agents represents one of the main obstacles for improving survival outcomes in AML patients. In our study, a new prognostic scale for the risk stratification of AML patients based on the detection of the sensitivity or resistance of tumor cells to chemotherapeutic drugs in vitro as well as MDR1 mRNA/P-glycoprotein expression, tumor origin (primary or secondary), cytogenetic abnormalities, and aberrant immunophenotype was developed. This study included 53 patients diagnosed with AML. Patients who received intensive or non-intensive induction therapy were analyzed separately. Using correlation, ROC, and Cox regression analyses, we show that the risk stratification of AML patients in accordance with the developed prognostic scale correlates well with the response to therapy and represents an independent predictive factor for the overall survival of patients with newly diagnosed AML.