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1.
Bioorg Med Chem Lett ; 110: 129889, 2024 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-39004318

RESUMO

Studies have shown that disrupting the formation of the ligand-RET-GFRα complex could be an effective way of treating pain and itch. Compared to traditional high-throughput screens, DNA encoded libraries (DELs) have distinguished themselves as a powerful technology for hit identification in recent years. The present work demonstrates the use of DEL technology identifying compound 16 as the first GFRa2/GFRa3 small molecule inhibitor (0.1/0.2 µM respectively) selective over RET. This molecule represents an opportunity to advance the development of small-molecule inhibitors targeting the GFRα-RET interface for the treatment of pain and itch.


Assuntos
DNA , Receptores de Fator Neurotrófico Derivado de Linhagem de Célula Glial , Bibliotecas de Moléculas Pequenas , Bibliotecas de Moléculas Pequenas/química , Bibliotecas de Moléculas Pequenas/farmacologia , Bibliotecas de Moléculas Pequenas/síntese química , Humanos , DNA/química , DNA/metabolismo , Receptores de Fator Neurotrófico Derivado de Linhagem de Célula Glial/metabolismo , Receptores de Fator Neurotrófico Derivado de Linhagem de Célula Glial/antagonistas & inibidores , Descoberta de Drogas , Relação Estrutura-Atividade , Estrutura Molecular , Relação Dose-Resposta a Droga
2.
Health Soc Work ; 49(3): 166-174, 2024 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-38869235

RESUMO

Out of all the racial groups in the United States, people who identify as American Indian and Alaska Native (AI/AN) have disproportionately worse health as a result of living in poverty. The preponderance of research connects poor health with a socioeconomic perspective, which might create prejudice against AI/AN. As already known, AI/AN's high rates of obesity, diabetes, and stroke in comparison with that of other ethnic groups are mainly derived from their impoverished economic conditions that have forced them to consume the food distributed by the U.S. government. When minority health is discussed generally, the ethnic density perspective explains a minority population's positive health despite low socioeconomic status. This perspective helps researchers and practitioners understand the connections of psychological and social factors with physical health and demonstrates positive health effects on minority groups. Despite the high correlation between ethnic density and health having been validated, little to no research has explored AI/AN's health from this perspective. Using 13,064 electronic health records, this research tests the relationship between AI/AN density and health outcomes. This article introduces an innovative analytical strategy (i.e., a data mining technique), which is ideal for discovering frequently appearing health outcomes in a group. The finding reveals positive relationships between health outcomes and AI/AN density.


Assuntos
Nativos do Alasca , Disparidades nos Níveis de Saúde , Indígenas Norte-Americanos , Humanos , Densidade Demográfica , Fatores Socioeconômicos , Estados Unidos
3.
Sci Rep ; 14(1): 3372, 2024 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-38336989

RESUMO

This study aimed to create Greenhouse Gas - Air Pollution Interactions and Synergies (GAINS)-Korea, an integrated model for evaluating climate and air quality policies in Korea, modeled after the international GAINS model. GAINS-Korea incorporates specific Korean data and enhances granularity for enabling local government-level analysis. The model includes source-receptor matrices used to simulate pollutant dispersion in Korea, generated through CAMx air quality modeling. GAINS-Korea's performance was evaluated by examining different scenarios for South Korea. The business as usual scenario projected emissions from 2010 to 2030, while the air quality scenario included policies to reduce air pollutants in line with air quality and greenhouse gas control plans. The maximum feasible reduction scenario incorporated more aggressive reduction technologies along with air quality measures. The developed model enabled the assessment of emission reduction effects by both greenhouse gas and air pollutant emission reduction policies across 17 local governments in Korea, including changes in PM2.5 (particulate matter less than 2.5 µm) concentration and associated benefits, such as reduced premature deaths. The model also provides a range of visualization tools for comparative analysis among different scenarios, making it a valuable resource for policy planning and evaluation, and supporting decision-making processes.

4.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-1018265

RESUMO

Objective:To evaluate the effect of five-element acupuncture on clinical symptoms, brain metabolism and immunoglobulin level in patients with chronic fatigue syndrome.Methods:It was a randomized controlled trial. A total of 94 patients with chronic fatigue syndrome in our hospital from January 2021 to January 2022 were selected and divided into two groups according to the random number table method, with 47 in each group. The conventional western medicine group was treated with conventional western medicine, and the five-element acupuncture group was treated with five-element acupuncture on the basis of the conventional western medicine group. Both groups were treated for 4 weeks. Before and after treatment, the serum levels of interferon-γ (IFN-γ), corticosterone (CORT), IL-2 and 5-hydroxytryptamine (5-HT) were detected by ELISA; the levels of natural killer (NK) cells, CD4 +, CD8 +, IgG and IgM were detected by flow cytometry; the whole body superconducting MRI scanner was used to scan T2 Flair, T2WI and TlWI sequences of the hippocampus, and the spectral curves and the areas under the peak of N-acetylaspartic acid (NAA), creatine (Cr) and choline (Cho) were obtained, and the ratios of Cho/Cr and NAA/Cr were calculated. the fatigue Scale-14 (FS-14) and Fatigue Severity Scale (FSS) were used to evaluate the fatigue state of the patients, and the Depression-Anxiety-Stress Scale-21 (DASS-21) and Beck Anxiety Inventory (BAI) were used to evaluate the anxiety state of the patients. Symptom Checklist 90 (SCL-90) and Somatic and Mental Health Report Score (SPHERE) were used to evaluate the quality of life of patients. And the clinical efficacy was evaluated. Results:After treatment, the levels of IgG, CD4 + and NK in the five-element acupuncture group were significantly higher than those in the conventional western medicine group ( t values were 4.76, 3.65, 6.42, respectively, P<0.01), and the level of IgM, CD8 + was significantly lower than that in the conventional western medicine group ( t values were 7.30, 4.79, P<0.01); the levels of IFN-γ, IL-2 and 5-HT in the observation group were significantly higher than those in the conventional western medicine group ( t values were 7.60, 4.05, 2.79, respectively, respectively, P<0.01), and the level of CORT was significantly lower than that in the conventional western medicine group ( t=6.72, P<0.01); the NAA/Cr levels in the left [(1.10±0.04) vs. (1.05±0.03), t=6.86] and right [(1.18±0.02) vs. (1.21±0.03), t=8.23] hippocampus of the experimental group were significantly higher than those in the conventional western medicine group ( P<0.01), and the Cho/Cr levels in the left [(1.08±0.04) vs. (1.03±0.03), t=5.70] and right [(1.17±0.02) vs. (1.20±0.03), t=5.71] hippocampus of the experimental group were significantly lower than those of the conventional western medicine group ( P<0.01). After treatment, the scores of physical fatigue, mental fatigue and FSS in the five-element acupuncture group were significantly lower than those in the conventional western medicine group ( t values were 8.08, 9.08 and 7.07, respectively, P<0.01). The scores of DASS-21, BAI, SCL-90 and SPHERE in the conventional western medicine group were significantly lower than those in the conventional western medicine group ( t values were 3.63, 5.77, 8.74, 5.92, respectively, P<0.01).The total effective rate was 95.74% (45/47) in the five-element acupuncture group and 82.98% (39/47) in the conventional western medicine group, and there was no significant difference between the two groups ( χ2=2.80, P=0.094). Conclusion:Five-elements acupuncture can improve the expression of T lymphocytes, increase the levels of immunoglobulin and NK, reduce the level of CORT, regulate the brain metabolism of NAA in the left and right hippocampus, improve the clinical symptoms and negative emotions, and improve the clinical efficacy and quality of life in patients with chronic fatigue syndrome.

5.
Br J Pharmacol ; 181(2): 295-316, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-37258706

RESUMO

Acute myeloid leukaemia (AML) continues to have a poor prognosis, warranting new therapeutic strategies. The bone marrow (BM) microenvironment consists of niches that interact with not only normal haematopoietic stem cells (HSC) but also leukaemia cells like AML. There are many adhesion molecules in the BM microenvironment; therein, integrins have been of central interest. AML cells express integrins that bind to ligands in the microenvironment, enabling adhesion of leukaemia cells in the microenvironment, thereby initiating intracellular signalling pathways that are associated with cell migration, cell proliferation, survival, and drug resistance that has been described to mediate cell adhesion-mediated drug resistance (CAM-DR). Identifying and targeting integrins in AML to interrupt interactions with the microenvironment have been pursued as a strategy to overcome CAM-DR. Here, we focus on the BM microenvironment and review the role of integrins in CAM-DR of AML and discuss integrin-targeting strategies. LINKED ARTICLES: This article is part of a themed issue on Cancer Microenvironment and Pharmacological Interventions. To view the other articles in this section visit http://onlinelibrary.wiley.com/doi/10.1111/bph.v181.2/issuetoc.


Assuntos
Integrinas , Leucemia Mieloide Aguda , Humanos , Integrinas/metabolismo , Leucemia Mieloide Aguda/tratamento farmacológico , Leucemia Mieloide Aguda/metabolismo , Medula Óssea/metabolismo , Células-Tronco Hematopoéticas , Moléculas de Adesão Celular/metabolismo , Microambiente Tumoral
6.
Bioorg Chem ; 139: 106747, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37531819

RESUMO

Ceramides impact a diverse array of biological functions and have been implicated in disease pathogenesis. The enzyme neutral ceramidase (nCDase) is a zinc-containing hydrolase and mediates the metabolism of ceramide to sphingosine (Sph), both in cells and in the intestinal lumen. nCDase inhibitors based on substrate mimetics, for example C6-urea ceramide, have limited potency, aqueous solubility, and micelle-free fraction. To identify non-ceramide mimetic nCDase inhibitors, hit compounds from an HTS campaign were evaluated in biochemical, cell based and in silico modeling approaches. A majority of small molecule nCDase inhibitors contained pharmacophores capable of zinc interaction but retained specificity for nCDase over zinc-containing acid and alkaline ceramidases, as well as matrix metalloprotease-3 and histone deacetylase-1. nCDase inhibitors were refined by SAR, were shown to be substrate competitive and were active in cellular assays. nCDase inhibitor compounds were modeled by in silico DOCK screening and by molecular simulation. Modeling data supports zinc interaction and a similar compound binding pose with ceramide. nCDase inhibitors were identified with notably improved activity and solubility in comparison with the reference lipid-mimetic C6-urea ceramide.


Assuntos
Ceramidas , Ceramidase Neutra , Domínio Catalítico , Ceramidas/química , Ceramidase Neutra/antagonistas & inibidores , Esfingosina/química
7.
Front Oncol ; 13: 1223296, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37434976
9.
Nat Commun ; 14(1): 3204, 2023 06 02.
Artigo em Inglês | MEDLINE | ID: mdl-37268630

RESUMO

Lipid droplets (LDs) are dynamic organelles that contain an oil core mainly composed of triglycerides (TAG) that is surrounded by a phospholipid monolayer and LD-associated proteins called perilipins (PLINs). During LD biogenesis, perilipin 3 (PLIN3) is recruited to nascent LDs as they emerge from the endoplasmic reticulum. Here, we analyze how lipid composition affects PLIN3 recruitment to membrane bilayers and LDs, and the structural changes that occur upon membrane binding. We find that the TAG precursors phosphatidic acid and diacylglycerol (DAG) recruit PLIN3 to membrane bilayers and define an expanded Perilipin-ADRP-Tip47 (PAT) domain that preferentially binds DAG-enriched membranes. Membrane binding induces a disorder to order transition of alpha helices within the PAT domain and 11-mer repeats, with intramolecular distance measurements consistent with the expanded PAT domain adopting a folded but dynamic structure upon membrane binding. In cells, PLIN3 is recruited to DAG-enriched ER membranes, and this requires both the PAT domain and 11-mer repeats. This provides molecular details of PLIN3 recruitment to nascent LDs and identifies a function of the PAT domain of PLIN3 in DAG binding.


Assuntos
Diglicerídeos , Perilipina-3 , Diglicerídeos/metabolismo , Retículo Endoplasmático/metabolismo , Gotículas Lipídicas/metabolismo , Metabolismo dos Lipídeos/fisiologia , Perilipina-1/metabolismo , Perilipina-3/metabolismo , Triglicerídeos/metabolismo
10.
Integr Biol (Camb) ; 152023 04 11.
Artigo em Inglês | MEDLINE | ID: mdl-37247849

RESUMO

The recurrence of cancer following chemotherapy treatment is a major cause of death across solid and hematologic cancers. In B-cell acute lymphoblastic leukemia (B-ALL), relapse after initial chemotherapy treatment leads to poor patient outcomes. Here we test the hypothesis that chemotherapy-treated versus control B-ALL cells can be characterized based on cellular physical phenotypes. To quantify physical phenotypes of chemotherapy-treated leukemia cells, we use cells derived from B-ALL patients that are treated for 7 days with a standard multidrug chemotherapy regimen of vincristine, dexamethasone, and L-asparaginase (VDL). We conduct physical phenotyping of VDL-treated versus control cells by tracking the sequential deformations of single cells as they flow through a series of micron-scale constrictions in a microfluidic device; we call this method Quantitative Cyclical Deformability Cytometry. Using automated image analysis, we extract time-dependent features of deforming cells including cell size and transit time (TT) with single-cell resolution. Our findings show that VDL-treated B-ALL cells have faster TTs and transit velocity than control cells, indicating that VDL-treated cells are more deformable. We then test how effectively physical phenotypes can predict the presence of VDL-treated cells in mixed populations of VDL-treated and control cells using machine learning approaches. We find that TT measurements across a series of sequential constrictions can enhance the classification accuracy of VDL-treated cells in mixed populations using a variety of classifiers. Our findings suggest the predictive power of cell physical phenotyping as a complementary prognostic tool to detect the presence of cells that survive chemotherapy treatment. Ultimately such complementary physical phenotyping approaches could guide treatment strategies and therapeutic interventions. Insight box Cancer cells that survive chemotherapy treatment are major contributors to patient relapse, but the ability to predict recurrence remains a challenge. Here we investigate the physical properties of leukemia cells that survive treatment with chemotherapy drugs by deforming individual cells through a series of micron-scale constrictions in a microfluidic channel. Our findings reveal that leukemia cells that survive chemotherapy treatment are more deformable than control cells. We further show that machine learning algorithms applied to physical phenotyping data can predict the presence of cells that survive chemotherapy treatment in a mixed population. Such an integrated approach using physical phenotyping and machine learning could be valuable to guide patient treatments.


Assuntos
Asparaginase , Leucemia , Humanos , Vincristina/uso terapêutico , Recidiva , Fenótipo , Leucemia/tratamento farmacológico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico
11.
Front Cell Dev Biol ; 11: 1134121, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37082620

RESUMO

As effective therapies for relapse and refractory B-cell acute lymphoblastic leukemia (B-ALL) remain problematic, novel therapeutic strategies are needed. Artemis is a key endonuclease in V(D)J recombination and nonhomologous end joining (NHEJ) of DNA double-strand break (DSB) repair. Inhibition of Artemis would cause chromosome breaks during maturation of RAG-expressing T- and B-cells. Though this would block generation of new B- and T-cells temporarily, it could be oncologically beneficial for reducing the proliferation of B-ALL and T-ALL cells by causing chromosome breaks in these RAG-expressing tumor cells. Currently, pharmacological inhibition is not available for Artemis. According to gene expression analyses from 207 children with high-risk pre-B acute lymphoblastic leukemias high Artemis expression is correlated with poor outcome. Therefore, we evaluated four compounds (827171, 827032, 826941, and 825226), previously generated from a large Artemis targeted drug screen. A biochemical assay using a purified Artemis:DNA-PKcs complex shows that the Artemis inhibitors 827171, 827032, 826941, 825226 have nanomolar IC50 values for Artemis inhibition. We compared these 4 compounds to a DNA-PK inhibitor (AZD7648) in three patient-derived B-ALL cell lines (LAX56, BLQ5 and LAX7R) and in two mature B-cell lines (3301015 and 5680001) as controls. We found that pharmacological Artemis inhibition substantially decreases proliferation of B-ALL cell lines while normal mature B-cell lines are not markedly affected. Inhibition of DNA-PKcs (which regulates Artemis) using the DNA-PK inhibitor AZD7648 had minor effects on these same primary patient-derived ALL lines, indicating that inhibition of V(D)J hairpin opening requires direct inhibition of Artemis, rather than indirect suppression of the kinase that regulates Artemis. Our data provides a basis for further evaluation of pharmacological Artemis inhibition of proliferation of B- and T-ALL.

13.
Curr Top Microbiol Immunol ; 436: 393-407, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36243854

RESUMO

Despite the therapeutic progress, relapse remains a major problem in the treatment of acute lymphoblastic leukemia (ALL). Most leukemia cells that survive chemotherapy are found in the bone marrow (BM), thus resistance to chemotherapy and other treatments may be partially attributed to pro-survival signaling to leukemic cells mediated by leukemia cell-microenvironment interactions. Adhesion of leukemia cells to BM stromal cells may lead to cell adhesion-mediated drug resistance (CAM-DR) mediating intracellular signaling changes that support survival of leukemia cells. In ALL and chronic lymphocytic leukemia (CLL), adhesion-mediated activation of the PI3K/AKT signaling pathway has been shown to be critical in CAM-DR. PI3K targeting inhibitors have been approved for CLL and have been evaluated preclinically in ALL. However, PI3K inhibition has yet to be approved for clinical use in ALL. Here, we review the role of PI3K signaling for normal hematopoietic and leukemia cells and summarize preclinical inhibitors of PI3K in ALL.


Assuntos
Leucemia Linfocítica Crônica de Células B , Células-Tronco Mesenquimais , Humanos , Leucemia Linfocítica Crônica de Células B/tratamento farmacológico , Células-Tronco Mesenquimais/metabolismo , Fosfatidilinositol 3-Quinases/genética , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Transdução de Sinais , Microambiente Tumoral
14.
Anal Biochem ; 643: 114577, 2022 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-35134389

RESUMO

Neutral ceramidase is a hydrolase of ceramide that has been implicated in multiple biologic processes, including inflammation and oncogenesis. Ceramides and other sphingolipids, belong to a family of N-acyl linked lipids that are biologically active in signaling, despite their limited structural functions. Ceramides are generally pro-apoptotic, while sphingosine and sphingosine-1-phosphate (S1P) exert proliferative and pro-oncogenic effects. Ceramidases are important regulators of ceramide levels that hydrolyze ceramide to sphingosine. Thus, ceramidase inhibition significantly increases the quantities of ceramide and its associated signaling. To better understand the function of ceramide, biochemical and cellular assays for enzymatic activity were developed and validated to identify inhibitors of human neutral ceramidase (nCDase). Here we review the measurement of nCDase activity both in vitro and in vivo.


Assuntos
Ceramidase Neutra/análise , Humanos , Ceramidase Neutra/genética , Ceramidase Neutra/metabolismo , Pseudomonas aeruginosa/enzimologia
15.
Cell Chem Biol ; 29(4): 555-571.e11, 2022 04 21.
Artigo em Inglês | MEDLINE | ID: mdl-34715055

RESUMO

Canonical targeting of Polycomb repressive complex 1 (PRC1) to repress developmental genes is mediated by cell-type-specific, paralogous chromobox (CBX) proteins (CBX2, 4, 6, 7, and 8). Based on their central role in silencing and their dysregulation associated with human disease including cancer, CBX proteins are attractive targets for small-molecule chemical probe development. Here, we have used a quantitative and target-specific cellular assay to discover a potent positive allosteric modulator (PAM) of CBX8. The PAM activity of UNC7040 antagonizes H3K27me3 binding by CBX8 while increasing interactions with nucleic acids. We show that treatment with UNC7040 leads to efficient and selective eviction of CBX8-containing PRC1 from chromatin, loss of silencing, and reduced proliferation across different cancer cell lines. Our discovery and characterization of UNC7040 not only reveals the most cellularly potent CBX8-specific chemical probe to date, but also corroborates a mechanism of Polycomb regulation by non-specific CBX nucleotide binding activity.


Assuntos
Neoplasias , Complexo Repressor Polycomb 1 , Proteínas de Ciclo Celular/metabolismo , Cromatina , Histonas/metabolismo , Humanos , Complexo Repressor Polycomb 1/genética , Complexo Repressor Polycomb 1/metabolismo , Proteínas do Grupo Polycomb/genética , Proteínas do Grupo Polycomb/metabolismo , Ligação Proteica
16.
Exp Ther Med ; 23(1): 47, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34934426

RESUMO

Treatment of resistant or recurrent acute lymphoblastic leukemia (ALL) remains a challenge. It was previously demonstrated that the adhesion molecule integrin α4, referred to hereafter as α4, mediates the cell adhesion-mediated drug resistance (CAM-DR) of B-cell ALL by binding to vascular cell adhesion molecule-1 (VCAM-1) on bone marrow stroma. In addition, it was previously observed that the blockade of α4 with natalizumab or inhibition using the small molecule antagonist TBC3486 sensitized relapsed ALL cells to chemotherapy. However, α4-targeted therapy is not clinically available for the treatment of leukemia to date. In the present study, the use of a novel non-peptidic small molecule integrin α4 antagonist, AVA4746, as a potential new approach to combat drug-resistant B-ALL was explored. An in vitro co-culture = model of primary B-ALL cells and an in vivo xenograft model of patient-derived B-ALL cells were utilized for evaluation of AVA4746. VLA-4 conformation activation, cell adhesion/de-adhesion, endothelial tube formation, in vivo leukemia cell mobilization and survival assays were performed. AVA4746 exhibited high affinity for binding to B-ALL cells, where it also efficiently blocked ligand-binding to VCAM-1. In addition, AVA4746 caused the functional de-adhesion of primary B-ALL cells from VCAM-1. Inhibition of α4 using AVA4746 also prevented angiogenesis in vitro and when applied in combination with chemotherapy consisting of Vincristine, Dexamethasone and L-asparaginase, it prolonged the survival of ~33% of the mice in an in vivo xenograft model of B-ALL. These data implicate the potential of targeting the α4-VCAM-1 interaction using AVA4746 for the treatment of drug-resistant B-lineage ALL.

17.
Front Oncol ; 11: 766888, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34926269

RESUMO

The PI3K/Akt pathway-and in particular PI3Kδ-is known for its role in drug resistant B-cell acute lymphoblastic leukemia (B-ALL) and it is often upregulated in refractory or relapsed B-ALL. Myc proteins are transcription factors responsible for transcribing pro-proliferative genes and c-Myc is often overexpressed in cancers. The chromatin regulator BRD4 is required for expression of c-Myc in hematologic malignancies including B-ALL. Previously, combination of BRD4 and PI3K inhibition with SF2523 was shown to successfully decrease Myc expression. However, the underlying mechanism and effect of dual inhibition of PI3Kδ/BRD4 in B-ALL remains unknown. To study this, we utilized SF2535, a novel small molecule dual inhibitor which can specifically target the PI3Kδ isoform and BRD4. We treated primary B-ALL cells with various concentrations of SF2535 and studied its effect on specific pharmacological on-target mechanisms such as apoptosis, cell cycle, cell proliferation, and adhesion molecules expression usingin vitro and in vivo models. SF2535 significantly downregulates both c-Myc mRNA and protein expression through inhibition of BRD4 at the c-Myc promoter site and decreases p-AKT expression through inhibition of the PI3Kδ/AKT pathway. SF2535 induced apoptosis in B-ALL by downregulation of BCL-2 and increased cleavage of caspase-3, caspase-7, and PARP. Moreover, SF2535 induced cell cycle arrest and decreased cell counts in B-ALL. Interestingly, SF2535 decreased the mean fluorescence intensity (MFI) of integrin α4, α5, α6, and ß1 while increasing MFI of CXCR4, indicating that SF2535 may work through inside-out signaling of integrins. Taken together, our data provide a rationale for the clinical evaluation of targeting PI3Kδ/BRD4 in refractory or relapsed B-ALL using SF2535.

18.
Blood Adv ; 5(20): 4233-4255, 2021 10 26.
Artigo em Inglês | MEDLINE | ID: mdl-34507353

RESUMO

Acute myeloid leukemia (AML) cells are highly dependent on oxidative phosphorylation (OxPhos) for survival, and they continually adapt to fluctuations in nutrient and oxygen availability in the bone marrow (BM) microenvironment. We investigated how the BM microenvironment affects the response to OxPhos inhibition in AML by using a novel complex I OxPhos inhibitor, IACS-010759. Cellular adhesion, growth, and apoptosis assays, along with measurements of expression of mitochondrial DNA and generation of mitochondrial reactive oxygen species indicated that direct interactions with BM stromal cells triggered compensatory activation of mitochondrial respiration and resistance to OxPhos inhibition in AML cells. Mechanistically, inhibition of OxPhos induced transfer of mitochondria derived from mesenchymal stem cells (MSCs) to AML cells via tunneling nanotubes under direct-contact coculture conditions. Inhibition of OxPhos also induced mitochondrial fission and increased functional mitochondria and mitophagy in AML cells. Mitochondrial fission is known to enhance cell migration, so we used electron microscopy to observe mitochondrial transport to the leading edge of protrusions of AML cells migrating toward MSCs. We further demonstrated that cytarabine, a commonly used antileukemia agent, increased mitochondrial transfer of MSCs to AML cells triggered by OxPhos inhibition. Our findings indicate an important role of exogenous mitochondrial trafficking from BM stromal cells to AML cells as well as endogenous mitochondrial fission and mitophagy in the compensatory adaptation of leukemia cells to energetic stress in the BM microenvironment.


Assuntos
Leucemia Mieloide Aguda , Fosforilação Oxidativa , Humanos , Leucemia Mieloide Aguda/tratamento farmacológico , Leucemia Mieloide Aguda/metabolismo , Mitocôndrias/metabolismo , Dinâmica Mitocondrial , Oxidiazóis , Piperidinas , Microambiente Tumoral
19.
Nat Commun ; 12(1): 4718, 2021 08 05.
Artigo em Inglês | MEDLINE | ID: mdl-34354069

RESUMO

Phospholipid synthesis and fat storage as triglycerides are regulated by lipin phosphatidic acid phosphatases (PAPs), whose enzymatic PAP function requires association with cellular membranes. Using hydrogen deuterium exchange mass spectrometry, we find mouse lipin 1 binds membranes through an N-terminal amphipathic helix, the Ig-like domain and HAD phosphatase catalytic core, and a middle lipin (M-Lip) domain that is conserved in mammalian and mammalian-like lipins. Crystal structures of the M-Lip domain reveal a previously unrecognized protein fold that dimerizes. The isolated M-Lip domain binds membranes both in vitro and in cells through conserved basic and hydrophobic residues. Deletion of the M-Lip domain in lipin 1 reduces PAP activity, membrane association, and oligomerization, alters subcellular localization, diminishes acceleration of adipocyte differentiation, but does not affect transcriptional co-activation. This establishes the M-Lip domain as a dimeric protein fold that binds membranes and is critical for full functionality of mammalian lipins.


Assuntos
Fosfatidato Fosfatase/química , Células 3T3-L1 , Adipogenia , Sequência de Aminoácidos , Animais , Membrana Celular/metabolismo , Sequência Conservada , Cristalografia por Raios X , Células HEK293 , Humanos , Espectrometria de Massa com Troca Hidrogênio-Deutério , Proteínas de Membrana/química , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo , Camundongos , Modelos Moleculares , Simulação de Dinâmica Molecular , Fosfatidato Fosfatase/genética , Fosfatidato Fosfatase/metabolismo , Ligação Proteica , Domínios Proteicos , Dobramento de Proteína , Multimerização Proteica , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Deleção de Sequência , Homologia de Sequência de Aminoácidos , Transcrição Gênica
20.
Cancers (Basel) ; 13(14)2021 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-34298603

RESUMO

Despite progress in the treatment of acute myeloid leukemia (AML), the clinical outcome remains suboptimal and many patients are still dying from this disease. First-line treatment consists of chemotherapy, which typically includes cytarabine (AraC), either alone or in combination with anthracyclines, but drug resistance can develop and significantly worsen prognosis. Better treatments are needed. We are developing a novel anticancer compound, NEO212, that was created by covalent conjugation of two different molecules with already established anticancer activity, the alkylating agent temozolomide (TMZ) and the natural monoterpene perillyl alcohol (POH). We investigated the anticancer activity of NEO212 in several in vitro and in vivo models of AML. Human HL60 and U937 AML cell lines, as well as different AraC-resistant AML cell lines, were treated with NEO212 and effects on cell proliferation, cell cycle, and cell death were investigated. Mice with implanted AraC-sensitive or AraC-resistant AML cells were dosed with oral NEO212, and animal survival was monitored. Our in vitro experiments show that treatment of cells with NEO212 results in growth inhibition via potent G2 arrest, which is followed by apoptotic cell death. Intriguingly, NEO212 was equally potent in highly AraC-resistant cells. In vivo, NEO212 treatment strikingly extended survival of AML mice and the majority of treated mice continued to thrive and survive without any signs of illness. At the same time, we were unable to detect toxic side effects of NEO212 treatment. All in all, the absence of side effects, combined with striking therapeutic activity even in an AraC-resistant context, suggests that NEO212 should be developed further toward clinical testing.

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