bims-scepro 2024-09-08 papers

bims-scepro

Biomed News

on Stem cell proteostasis

Issue of 2024–09–08
fiveteen papers selected by
William Grey, University of York

Trained and ready - the case for an inflammatory memory for hematopoietic stem and progenitor cells in the AML niche.
NFAT5 counters long-term IFN-I responses in hematopoietic stem cells to preserve reconstitution potential.
Rejuvenation of the reconstitution potential and reversal of myeloid bias of aged HSCs upon pH treatment.
A STAT3 Degrader Demonstrates Pre-clinical Efficacy in Venetoclax resistant Acute Myeloid Leukemia.
The Clonal Hematopoiesis-associated Gene Srcap Plays an Essential Role in Hematopoiesis.
Long-term engrafting multilineage hematopoietic cells differentiated from human induced pluripotent stem cells.
Smarcd1 subunit of SWI/SNF chromatin-remodeling complexes collaborates with E2a to promote murine lymphoid specification.
Hematopoietic Stem Cell Fates and the Cellular Hierarchy of Mammalian Hematopoiesis: from Transplantation Models to New Insights from in Situ Analyses.
TP53-Mutated Acute Myeloid Leukemia: How Can We Improve Outcomes?
USP13 promotes acute myeloid leukemia cell proliferation and autophagy by promoting ATG5.
Bithionol eliminates acute myeloid leukaemia stem-like cells by suppressing NF-κB signalling and inducing oxidative stress, leading to apoptosis and ferroptosis.
Mitochondrial dsRNA from B-ALL cells stimulates mesenchymal stromal cells to become cancer associated fibroblasts.
PROTAC-DB 3.0: an updated database of PROTACs with extended pharmacokinetic parameters.
Targeting NLRP3 inhibits AML progression by inducing PERK/eIF2-mediated apoptosis.
Efficient generation of human NOTCH ligand-expressing haemogenic endothelial cells as infrastructure for in vitro haematopoiesis and lymphopoiesis.

Oncotarget. 2024 Sep 04. 15 609-613

Trained and ready - the case for an inflammatory memory for hematopoietic stem and progenitor cells in the AML niche.

Ding-Wen Chen, Eric K Wafula, Peter Kurre.

  Lifelong hematopoiesis is sustained by crosstalk between hematopoietic stem and progenitor cells (HSPCs) and specialized bone marrow niches. Acute myeloid leukemia (AML) upends that balance, as leukemic blasts secrete factors that remodel the bone marrow into a self-reinforcing leukemic niche. The inflammatory secretome behind this compartmental adaptation accounts for a progressive decline in hematopoietic function that leads to diagnosis and persists through early treatment. Not surprisingly, the mediators of an acute inflammatory injury and HSPC suppression have attracted much attention in an effort to alleviate morbidity and improve outcomes. HSPCs typically recover during disease remission and re-expand in the bone marrow (BM), but little is known about potentially lasting consequences for stem cells and progenitors. We recently showed that AML-experienced HSPCs actively participate in the inflammatory process during leukemic progression. HSPCs are constituent components of the innate immune system, and elegant studies of infection and experimental inflammation over the past decade have described the generation of an adoptively transferable, innate immune memory. Building on this paradigm, we discuss the potential translational relevance of a durable legacy in AML-experienced HSPC.

Keywords:  acute myeloid leukemia; hematopoietic stem and progenitor cells; inflammation; innate immune reprogramming; trained immunity

DOI:  https://doi.org/10.18632/oncotarget.28642
Blood Adv. 2024 Aug 29. pii: bloodadvances.2023011306. [Epub ahead of print]

NFAT5 counters long-term IFN-I responses in hematopoietic stem cells to preserve reconstitution potential.

Laia Traveset, Víctor Cerdán Porqueras, Hector Huerga Encabo, Silvia Avalle, Anna Esteve-Codina, Oscar Fornas, Jose Aramburu, Cristina Lopez-Rodriguez.

Hematopoietic stem cells (HSCs) readily recover from acute stress, but persistent stress can reduce their viability and long-term potential. Here we show that the nuclear factor of activated T cells 5 (NFAT5), a transcription modulator of inflammatory responses, protects the HSC pool under stress. NFAT5 restrains HSC differentiation to multipotent progenitors (MPPs) after bone marrow transplantation and bone marrow ablation with ionizing radiation or chemotherapy. Correspondingly, NFAT5-deficient HSCs fail to support long-term reconstitution of hematopoietic progenitors and mature blood cells after serial transplant. Evidence from competitive transplant assays shows that these defects are HSC-intrinsic. NFAT5-deficient HSCs exhibit enhanced expression of type I interferon (IFN-I) response genes after transplant, and suppressing IFN-I-receptor prevents their exacerbated differentiation and cell death after reconstitution and improves long-term regeneration potential. Blockade of IFN-I receptor also prevented the overdifferentiation of NFAT5-deficient HSCs after bone marrow ablation. These findings show that long-term IFN-I responses to different hematopoietic stressors drive HSCs towards more differentiated progenitors, and that NFAT5 has an HSC-intrinsic role limiting IFN-I responses to preserve reconstitution potential. Our identification of cell-intrinsic mechanisms that strengthen the resistance of HSCs to stress could help to devise approaches to protect long-term stemness during the treatment of hematopoietic malignancies.

DOI: https://doi.org/10.1182/bloodadvances.2023011306
Aging Cell. 2024 Sep 05. e14324

Rejuvenation of the reconstitution potential and reversal of myeloid bias of aged HSCs upon pH treatment.

Sachin Kumar, Jeffrey D Vassallo, Kalpana J Nattamai, Aishlin Hassan, Angelika Vollmer, Rebekah Karns, Mehmet Sacma, Travis Nemkov, Angelo D'Alessandro, Hartmut Geiger.

  Aged hematopoietic stem cells (HSCs) show reduced reconstitution potential, limiting their use in transplantation settings in the clinic. We demonstrate here that exposure of aged HSCs ex vivo to a pH of 6.9 instead of the commonly used pH of 7.4 results in enhanced HSCs potential that is consistent with rejuvenation, including attenuation of the myeloid bias of aged HSC and restoration of a youthful frequency of epigenetic polarity. Rejuvenation of aged HSCs by pH 6.9 is, at least in part, due to alterations in the polyamine/methionine pathway within pH 6.9 HSCs, and consequently, attenuation of the production of spermidine also attenuated aging of HSCs. Exposure of aged HSCs to pH 6.9, or pharmacological targeting of the polyamine pathway, might thus extend the use of HSCs from aged donors for therapeutic applications.

Keywords:  aging; hematopoietic stem cells; pH; polyamine; rejuvenation

DOI:  https://doi.org/10.1111/acel.14324
bioRxiv. 2024 Aug 07. pii: 2024.08.05.599788. [Epub ahead of print]

A STAT3 Degrader Demonstrates Pre-clinical Efficacy in Venetoclax resistant Acute Myeloid Leukemia.

Samarpana Chakraborty, Claudia Morganti, Bianca Rivera Pena, Hui Zhang, Divij Verma, Kimberly Zaldana, Nadege Gitego, Feiyang Ma, Srinivas Aluri, Kith Pradhan, Shanisha Gordon, Ioannis Mantzaris, Mendel Goldfinger, Eric Feldman, Kira Gritsman, Yang Shi, Stefan Hubner, Yi Hua Qiu, Brandon D Brown, Anna Skwarska, Amit Verma, Marina Konopleva, Yoko Tabe, Evripidis Gavathiotis, Simona Colla, Jared Gollob, Joyoti Dey, Steven M Kornblau, Sergei B Koralov, Keisuke Ito, Aditi Shastri.

Acute myeloid leukemia (AML) is an aggressive hematologic malignancy that continues to have poor prognosis despite recent therapeutic advances. Venetoclax (Ven), a BCL2-inhibitor has shown a high response rate in AML; however, relapse is invariable due to mitochondrial dysregulation that includes upregulation of the antiapoptotic protein MCL1, a central mechanism of Ven resistance (Ven-res). We have previously demonstrated that the transcription factor STAT3 is upregulated in AML hematopoietic stem and progenitor cells (HSPCs) and can be effectively targeted to induce apoptosis of these aberrant cells. We now show that overexpression of STAT3 alone is sufficient to initiate a strong AML phenotype in a transgenic murine model. Phospho-proteomic data from Ven treated AML patients show a strong correlation of high total STAT3 and phospho-STAT3 [both p-STAT3(Y705) and p-STAT3(S727)] expression with worse survival and reduced remission duration. Additionally, significant upregulation of STAT3 was observed in Ven-res cell lines, in vivo models and primary patient samples. A novel and specific degrader of STAT3 demonstrated targeted reduction of total STAT3 and resulting inhibition of its active p-STAT3(Y705) and p-STAT3(S727) forms. Treatment with the STAT3 degrader induced apoptosis in parental and Ven-res AML cell lines and decreased mitochondrial depolarisation, and thereby dependency on MCL1 in Ven-res AML cell line, as observed by BH3 profiling assay. STAT3 degrader treatment also enhanced differentiation of myeloid and erythroid colonies in Ven-res peripheral blood mononuclear cells (PBMNCs). Upregulation of p-STAT3(S727) was also associated with pronounced mitochondrial structural and functional dysfunction in Ven-res cell lines, that were restored by STAT3 degradation. Treatment with a clinical-stage STAT3 degrader, KT-333 resulted in a significant reduction in STAT3 and MCL1 protein levels within two weeks of treatment in a cell derived xenograft model of Ven-res AML. Additionally, this treatment significant improvement in the survival of a Ven-res patient-derived xenograft in-vivo study. Degradation of STAT3 resulting in downregulation of MCL1 and improvements in global mitochondrial dysfunction suggests a novel mechanism of overcoming Ven-res in AML.
Statement of Purpose: Five-year survival from AML is dismal at 30%. Our prior research demonstrated STAT3 over-expression in AML HSPC's to be associated with inferior survival. We now explore STAT3 over-expression in Ven-res AML, explain STAT3 mediated mitochondrial perturbations and describe a novel therapeutic strategy, STAT3 degradation to overcome Ven-res.

DOI: https://doi.org/10.1101/2024.08.05.599788
bioRxiv. 2024 Aug 19. pii: 2024.08.16.607812. [Epub ahead of print]

The Clonal Hematopoiesis-associated Gene Srcap Plays an Essential Role in Hematopoiesis.

Terrence N Wong, Anna Mychalowych, Ellie R Feldpausch, Alexander Carson, Darja Karpova, Daniel C Link.

Somatic mutations arising in hematopoietic stem cells (HSCs) may provide the latter with a fitness advantage, allowing the mutant HSC to clonally expand. Such mutations have been recurrently identified in the chromatin modifier, SRCAP , in both non-malignant and leukemic clones, suggesting that this gene plays a significant role in hematopoiesis. We generated a conditional Srcap loss of function murine model and determined the consequences of hematopoietic-specific loss of this gene. We show that Srcap is essential for normal fetal liver erythropoiesis and monocytopoiesis. In Srcap deficient fetal livers, the number of phenotypic HSCs is similar to that of controls, but these HSCs exhibit a profound repopulating defect. Likewise, conditional deletion of Srcap during adult hematopoiesis results in a rapid loss of HSCs. Loss of Srcap is associated with evidence of increased DNA damage in HSCs and lineage-restricted progenitors as assessed by y-H2AX expression. Consistent with this finding, we observed strong transcriptional upregulation of the p53 pathway in Srcap deficient erythroid precursors. Collectively our data highlight the importance of Srcap in maintaining HSC function and supporting hematopoietic differentiation and suggests that it plays an essential role in maintaining genomic integrity.
Key Points: Srcap plays an essential role in supporting normal hematopoietic differentiation. and in maintaining HSC function. Loss of Srcap is associated with evidence of increased DNA damage and transcriptional upregulation of the p53 pathway.

DOI: https://doi.org/10.1101/2024.08.16.607812
Nat Biotechnol. 2024 Sep 02.

Long-term engrafting multilineage hematopoietic cells differentiated from human induced pluripotent stem cells.

Elizabeth S Ng, Gulcan Sarila, Jacky Y Li, Hasindu S Edirisinghe, Ritika Saxena, Shicheng Sun, Freya F Bruveris, Tanya Labonne, Nerida Sleebs, Alexander Maytum, Raymond Y Yow, Chantelle Inguanti, Ali Motazedian, Vincenzo Calvanese, Sandra Capellera-Garcia, Feiyang Ma, Hieu T Nim, Mirana Ramialison, Constanze Bonifer, Hanna K A Mikkola, Edouard G Stanley, Andrew G Elefanty.

Hematopoietic stem cells (HSCs) derived from human induced pluripotent stem cells (iPS cells) have important biomedical applications. We identified differentiation conditions that generate HSCs defined by robust long-term multilineage engraftment in immune-deficient NOD,B6.Prkdcscid Il2rgtm1Wjl/SzJ KitW41/W41 mice. We guided differentiating iPS cells, as embryoid bodies in a defined culture medium supplemented with retinyl acetate, through HOXA-patterned mesoderm to hemogenic endothelium specified by bone morphogenetic protein 4 and vascular endothelial growth factor (VEGF). Removal of VEGF facilitated an efficient endothelial-to-hematopoietic transition, evidenced by release into the culture medium of CD34+ blood cells, which were cryopreserved. Intravenous transplantation of two million thawed CD34+ cells differentiated from four independent iPS cell lines produced multilineage bone marrow engraftment in 25-50% of immune-deficient recipient mice. These functionally defined, multipotent CD34+ hematopoietic cells, designated iPS cell-derived HSCs (iHSCs), produced levels of engraftment similar to those achieved following umbilical cord blood transplantation. Our study provides a step toward the goal of generating HSCs for clinical translation.

DOI: https://doi.org/10.1038/s41587-024-02360-7
Dev Cell. 2024 Aug 30. pii: S1534-5807(24)00490-8. [Epub ahead of print]

Smarcd1 subunit of SWI/SNF chromatin-remodeling complexes collaborates with E2a to promote murine lymphoid specification.

Pierre Priam, Veneta Krasteva, Philippe Rousseau, Alexandre Polsinelli, Laurence Côté, Ines Desanlis, Azer Farah, Vincent-Philippe Lavallée, Marie Kmita, Julie A Lessard.

  Lymphocyte development from murine hematopoietic stem cells (HSCs) entails a loss of self-renewal capacity and a progressive restriction of developmental potential. Previous research from our laboratory suggests that specialized assemblies of ATP-dependent SWI/SNF chromatin-remodeling complexes play lineage-specific roles during murine hematopoiesis. Here, we demonstrate that the Smarcd1 subunit is essential for specification of lymphoid cell fate from multipotent progenitors. Acute deletion of Smarcd1 in murine adult hematopoiesis leads to lymphopenia, characterized by a near-complete absence of early lymphoid progenitors and mature B and T cells, while the myeloid and erythroid lineages remain unaffected. Mechanistically, we demonstrate that Smarcd1 is essential for the coordinated activation of a lymphoid gene signature in murine multipotent progenitors. This is achieved by interacting with the E2a transcription factor at proximal promoters and by regulating the activity of distal enhancers. Globally, these findings identify Smarcd1 as an essential chromatin remodeler that governs lymphoid cell fate.

Keywords:  E2a/Tcf3; SWI/SNF complexes; Smarcd1/BAF60a; active enhancers; chromatin remodeling; lymphoid priming; lymphopenia

DOI:  https://doi.org/10.1016/j.devcel.2024.08.007
Stem Cell Rev Rep. 2024 Sep 02.

Hematopoietic Stem Cell Fates and the Cellular Hierarchy of Mammalian Hematopoiesis: from Transplantation Models to New Insights from in Situ Analyses.

Dania Shaban, Nay Najm, Lucie Droin, Anastasia Nijnik.

  Hematopoiesis is the process that generates the cells of the blood and immune system from hematopoietic stem and progenitor cells (HSPCs) and represents the system with the most rapid cell turnover in a mammalian organism. HSPC differentiation trajectories, their underlying molecular mechanisms, and their dysfunctions in hematologic disorders are the focal research questions of experimental hematology. While HSPC transplantations in murine models are the traditional tool in this research field, recent advances in genome editing and next generation sequencing resulted in the development of many fundamentally new approaches for the analyses of mammalian hematopoiesis in situ and at single cell resolution. The current review will cover many recent developments in this field in murine models, from the bulk lineage tracing studies of HSPC differentiation to the barcoding of individual HSPCs with Cre-recombinase, Sleeping Beauty transposase, or CRISPR/Cas9 tools, to map hematopoietic cell fates, together with their transcriptional and epigenetic states. We also address studies of the clonal dynamics of human hematopoiesis, from the tracing of HSPC clonal behaviours based on viral integration sites in gene therapy patients to the recent analyses of unperturbed human hematopoiesis based on naturally accrued mutations in either nuclear or mitochondrial genomes. Such studies are revolutionizing our understanding of HSPC biology and hematopoiesis both under homeostatic conditions and in the response to various forms of physiological stress, reveal the mechanisms responsible for the decline of hematopoietic function with age, and in the future may advance the understanding and management of the diverse disorders of hematopoiesis.

Keywords:  Genetic barcoding; Hematopoiesis; Hematopoietic progenitor cells; Hematopoietic stem cells; Lineage tracing and fate mapping studies

DOI:  https://doi.org/10.1007/s12015-024-10782-8
Blood. 2024 Sep 05. pii: blood.2024024245. [Epub ahead of print]

TP53-Mutated Acute Myeloid Leukemia: How Can We Improve Outcomes?

David A Sallman, Maximilian Stahl.

Despite advances in the treatment paradigm of patients with acute myeloid leukemia (AML), TP53 mutated AML represents a molecular subgroup that has failed to improve with an overall survival around 6 months that is independent of age and fitness. Notably, there has been significant elucidation in understanding the biology of the disease and key advancements in the classification and prognostication of these patients. International collaborative efforts of novel clinical interventions are urgently needed to change the standard of care.

DOI: https://doi.org/10.1182/blood.2024024245
Tissue Cell. 2024 Aug 09. pii: S0040-8166(24)00195-2. [Epub ahead of print]91 102494

USP13 promotes acute myeloid leukemia cell proliferation and autophagy by promoting ATG5.

Yuchu Yuan, Meizhu Xue, Feng Zhou, Lifang Gu.

   OBJECTIVE: To elucidate the role of USP13 in acute myeloid leukemia (AML) by investigating its effects on cell growth, apoptosis and autophagy, and to explore the underlying mechanisms.
METHODS: The expression of USP13 in AML cells was assessed using quantitative PCR (qPCR) and immunoblotting. Cell Counting Kit-8 (CCK-8) and Edu staining were employed to evaluate the impact of USP13 on AML cell growth. Terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) and immunostaining assays were conducted to examine the effects of USP13 on apoptosis and autophagy in AML cells, and immunoblot assays were performed to determine the potential underlying mechanistic pathway.
RESULTS: USP13 expression was significantly elevated in AML cells, correlating with enhanced cell proliferation and resistance to apoptosis. Moreover, USP13 promoted autophagy in AML cells. Mechanistically, USP13 was found to be associated with upregulating ATG5 expression, which promoted AML progression.
CONCLUSION: USP13 promotes AML cell growth and autophagy by upregulating ATG5.

Keywords:  ATG5; Acute myeloid leukemia (AML); Apoptosis; Autophagy; USP13

DOI:  https://doi.org/10.1016/j.tice.2024.102494
Cell Death Discov. 2024 Aug 29. 10(1): 390

Bithionol eliminates acute myeloid leukaemia stem-like cells by suppressing NF-κB signalling and inducing oxidative stress, leading to apoptosis and ferroptosis.

Ingrid R S B Dias, Rafaela G A Costa, Ana Carolina B da C Rodrigues, Suellen L R Silva, Maiara de S Oliveira, Milena B P Soares, Rosane B Dias, Ludmila F Valverde, Clarissa A Gurgel Rocha, Lauren V Cairns, Ken I Mills, Daniel P Bezerra.

Acute myeloid leukaemia (AML) is a lethal bone marrow neoplasm caused by genetic alterations in blood cell progenitors. Leukaemic stem cells (LSCs) are responsible for the development of AML, drug resistance and relapse. Bithionol is an old anthelmintic drug with potential antibacterial, antiviral, antifungal, anti-Alzheimer, and antitumour properties. In this work, we focused on the anti-AML LSC properties of bithionol. This compound inhibited the viability of both solid and haematological cancer cells, suppressed AML stem-like cells, and inhibited AML growth in NSG mice at a dosage of 50 mg/kg, with tolerable systemic toxicity. Bithionol significantly reduced the levels of phospho-NF-κB p65 (Ser529) and phospho-NF-κB p65 (Ser536) and nuclear NF-κB p65 translocation in AML cells, indicating that this molecule can suppress NF-κB signalling. DNA fragmentation, nuclear condensation, cell shrinkage, phosphatidylserine externalisation, loss of transmembrane mitochondrial potential, caspase-3 activation and PARP-(Asp 214) cleavage were detected in bithionol-treated AML cells, indicating the induction of apoptosis. Furthermore, this compound increased mitochondrial superoxide levels, and bithionol-induced cell death was partially prevented by cotreatment with the selective ferroptosis inhibitor ferrostatin-1, indicating the induction of ferroptosis. In addition, bithionol synergised with venetoclax in AML cells, indicating the translational potential of bithionol to enhance the effects of venetoclax in patients with AML. Taken together, these data indicate that bithionol is a potential new anti-AML drug.

DOI: https://doi.org/10.1038/s41420-024-02148-3
Blood Adv. 2024 Sep 03. pii: bloodadvances.2023012077. [Epub ahead of print]

Mitochondrial dsRNA from B-ALL cells stimulates mesenchymal stromal cells to become cancer associated fibroblasts.

Richard Burt, Aditi Dey, Ayse Akarca, Hermione Allen, Rodothea Amerikanou, Samantha Atkinson, David Auty, Jenny Chatzigerou, Emily Annie Cutler, Jose Afonso Guerra-Assuncao, Kristina Kirschner, Ruchi Kumari, Jiten Manji, Teresa Marafioti, Juma Ward, Adele K Fielding.

Cancer associated fibroblasts (CAF) arising from bone marrow-derived mesenchymal stromal cells (MSC) are prominent in B-precursor acute lymphoblastic leukaemia (B-ALL). We have previously shown that CAF formation is triggered by exposure to reactive oxygen species-inducing chemotherapy and that CAF support chemoresistance by donating mitochondria to the cancer cells, through tunnelling nanotubes. In the present study, we show that exposure of MSC to ALL cell lines, patient-derived xenografts and primary cells or their conditioned media can also trigger CAF formation. Using bulk RNA sequencing in cell lines, we show that the MSC to CAF transition is accompanied by a robust interferon pathway response and we have validated this finding in primary cells. Using confocal microscopy and flow cytometry, we identify the take-up of leukaemia cell-derived mitochondrial dsRNA by MSC as a proximate trigger for the MSC to CAF transition. We show that inhibition of dsRNA formation in ALL cells by treatment with low-dose ethidium or the mitochondrial transcription inhibitor IMT1 or degradation of dsRNA in conditioned media by 100°C exposure ablates the ability of the ALL conditioned media to stimulate MSC to CAF transition. Our data reveal a novel and previously undescribed mechanism by which cancer cells induce a CAF phenotype in stromal cells, showing how B-ALL cells can directly induce the previously described niche-mediated protection within the bone marrow.

DOI: https://doi.org/10.1182/bloodadvances.2023012077
Nucleic Acids Res. 2024 Sep 03. pii: gkae768. [Epub ahead of print]

PROTAC-DB 3.0: an updated database of PROTACs with extended pharmacokinetic parameters.

Jingxuan Ge, Shimeng Li, Gaoqi Weng, Huating Wang, Meijing Fang, Huiyong Sun, Yafeng Deng, Chang-Yu Hsieh, Dan Li, Tingjun Hou.

Proteolysis-targeting chimera (PROTAC) is an emerging therapeutic technology that leverages the ubiquitin-proteasome system to target protein degradation. Due to its event-driven mechanistic characteristics, PROTAC has the potential to regulate traditionally non-druggable targets. Recently, AI-aided drug design has accelerated the development of PROTAC drugs. However, the rational design of PROTACs remains a considerable challenge. Here, we present an updated online database, PROTAC-DB 3.0. In this third version, we have expanded the database to include 6111 PROTACs (87% increase compared to the 2.0 version). Additionally, the database now contains 569 warheads (small molecules targeting the protein), 2753 linkers, and 107 E3 ligands (small molecules recruiting E3 ligases). The number of target-PROTAC-E3 ternary complex structures has also increased to 959. Recognizing the importance of druggability in PROTAC design, we have incorporated pharmacokinetic data to PROTAC-DB 3.0. To enhance user experience, we have added features for sorting based on molecular similarity and literature publication date. PROTAC-DB 3.0 is accessible at http://cadd.zju.edu.cn/protacdb/.

DOI: https://doi.org/10.1093/nar/gkae768
Cell Commun Signal. 2024 Sep 02. 22(1): 424

Targeting NLRP3 inhibits AML progression by inducing PERK/eIF2-mediated apoptosis.

Michela Luciano, Helene Sieberer, Peter W Krenn, Hieu-Hoa Dang, Julia Vetter, Theresa Neuper, Diana Amend, Constantin Blöchl, Christian X Weichenberger, Anna Eglseer, Michael S Unger, Ancuela Andosch, Philip Steiner, Daniel Neureiter, Renate Bauer, Laura Hummer, Suzana Tesanovic, Stephanie Binder, Dominik P Elmer, Helen Strandt, Susanne Schaller, Dirk Strunk, Lisa Pleyer, Richard Greil, Stephan Winkler, Tanja N Hartmann, Dirk Schmidt-Arras, Christian G Huber, Fritz Aberger, Jutta Horejs-Hoeck.

   BACKGROUND: Acute myeloid leukemia (AML) is characterized by the abnormal proliferation of myeloid precursor cells and presents significant challenges in treatment due to its heterogeneity. Recently, the NLRP3 inflammasome has emerged as a potential contributor to AML pathogenesis, although its precise mechanisms remain poorly understood.
METHODS: Public genome datasets were utilized to evaluate the expression of NLRP3 inflammasome-related genes (IL-1β, IL-18, ASC, and NLRP3) in AML patients compared to healthy individuals. CRISPR/Cas9 technology was employed to generate NLRP3-deficient MOLM-13 AML cells, followed by comprehensive characterization using real-time PCR, western blotting, FACS analysis, and transmission electron and immunofluorescence microscopy. Proteomic analyses were conducted to identify NLRP3-dependent alterations in protein levels, with a focus on the eIF2 kinase PERK-mediated signaling pathways. Additionally, in vivo studies were performed using a leukemic mouse model to elucidate the pathogenic role of NLRP3 in AML.
RESULTS: Elevated expression of NLRP3 was significantly associated with diminished overall survival in AML patients. Genetic deletion, pharmacological inhibition and silencing by RNA interference of NLRP3 led to decreased AML cell survival through the induction of apoptosis. Proteomic analyses uncovered NLRP3-dependent alterations in protein translation, characterized by enhanced eIF2α phosphorylation in NLRP3-deficient AML cells. Moreover, inhibition of PERK-mediated eIF2α phosphorylation reduced apoptosis by downregulating pro-apoptotic Bcl-2 family members. In vivo studies demonstrated reduced leukemic burden in mice engrafted with NLRP3 knockout AML cells, as evidenced by alleviated leukemic symptoms.
CONCLUSION: Our findings elucidate the involvement of the NLRP3/PERK/eIF2 axis as a novel driver of AML cell survival. Targeting NLRP3-induced signaling pathways, particularly through the PERK/eIF2 axis, presents a promising therapeutic strategy for AML intervention. These insights into the role of the NLRP3 inflammasome offer potential avenues for improving the prognosis and treatment outcomes of AML patients.

Keywords:  Acute myeloid leukemia; Apoptosis; PERK; eIF2α, NLRP3

DOI:  https://doi.org/10.1186/s12964-024-01777-6
Nat Commun. 2024 Sep 04. 15(1): 7698

Efficient generation of human NOTCH ligand-expressing haemogenic endothelial cells as infrastructure for in vitro haematopoiesis and lymphopoiesis.

Shicheng Sun, Ali Motazedian, Jacky Y Li, Kevin Wijanarko, Joe Jiang Zhu, Kothila Tharmarajah, Kathleen A Strumila, Anton Shkaruta, L Rayburn Nigos, Jacqueline V Schiesser, Yi Yu, Paul J Neeson, Elizabeth S Ng, Andrew G Elefanty, Edouard G Stanley.

Arterial endothelial cells (AECs) are the founder cells for intraembryonic haematopoiesis. Here, we report a method for the efficient generation of human haemogenic DLL4+ AECs from pluripotent stem cells (PSC). Time-series single-cell RNA-sequencing reveals the dynamic evolution of haematopoiesis and lymphopoiesis, generating cell types with counterparts present in early human embryos, including stages marked by the pre-haematopoietic stem cell genes MECOM/EVI1, MLLT3 and SPINK2. DLL4+ AECs robustly support lymphoid differentiation, without the requirement for exogenous NOTCH ligands. Using this system, we find IL7 acts as a morphogenic factor determining the fate choice between the T and innate lymphoid lineages and also plays a role in regulating the relative expression level of RAG1. Moreover, we document a developmental pathway by which human RAG1+ lymphoid precursors give rise to the natural killer cell lineage. Our study describes an efficient method for producing lymphoid progenitors, providing insights into their endothelial and haematopoietic ontogeny, and establishing a platform to investigate the development of the human blood system.

DOI: https://doi.org/10.1038/s41467-024-51974-7