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The 2023 Canadian forest fires have been extreme in scale and intensity with more than seven times the average annual area burned compared to the previous four decades1. Here, we quantify the carbon emissions from these fires from May to September 2023 on the basis of inverse modelling of satellite carbon monoxide observations. We find that the magnitude of the carbon emissions is 647 TgC (570-727 TgC), comparable to the annual fossil fuel emissions of large nations, with only India, China and the USA releasing more carbon per year2. We find that widespread hot-dry weather was a principal driver of fire spread, with 2023 being the warmest and driest year since at least 19803. Although temperatures were extreme relative to the historical record, climate projections indicate that these temperatures are likely to be typical during the 2050s, even under a moderate climate mitigation scenario (shared socioeconomic pathway, SSP 2-4.5)4. Such conditions are likely to drive increased fire activity and suppress carbon uptake by Canadian forests, adding to concerns about the long-term durability of these forests as a carbon sink5-8.
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Carbono , Florestas , Incêndios Florestais , Canadá , Carbono/análise , Carbono/química , Dióxido de Carbono/análise , Monóxido de Carbono/análise , Sequestro de Carbono , Modelos Climáticos , Secas , Combustíveis Fósseis/efeitos adversos , História do Século XXI , Temperatura Alta , Fatores Socioeconômicos , Incêndios Florestais/história , Incêndios Florestais/estatística & dados numéricosRESUMO
Carcinomas are common in humans but rare among closely related "great apes." Plausible explanations, including human-specific genomic alterations affecting the biology of sialic acids, are proposed, but causality remains unproven. Here, an integrated evolutionary genetics-phenome-transcriptome approach studied the role of SIGLEC12 gene (encoding Siglec-XII) in epithelial transformation and cancer. Exogenous expression of the protein in cell lines and genetically engineered mice recapitulated approximately 30% of the human population in whom the protein is expressed in a form that cannot bind ligand because of a fixed, homozygous, human-universal missense mutation. Siglec-XII-null cells/mice recapitulated the remaining approximately 70% of the human population in whom an additional polymorphic frameshift mutation eliminates the entire protein. Siglec-XII expression drove several pro-oncogenic phenotypes in cell lines and increased tumor burden in mice challenged with chemical carcinogen and inflammation. Transcriptomic studies yielded a 29-gene signature of Siglec-XII-positive disease and when used as a computational tool for navigating human data sets, pinpointed with surprising precision that SIGLEC12 expression (model) recapitulates a very specific type of colorectal carcinomas (disease) that is associated with mismatch-repair defects and inflammation, disproportionately affects European Americans, and carries a favorable prognosis. They revealed a hitherto-unknown evolutionary genetic mechanism for an ethnic/environmental predisposition of carcinogenesis.
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Neoplasias Colorretais , Inflamação , Animais , Humanos , Camundongos , Neoplasias Colorretais/genética , Neoplasias Colorretais/patologia , Neoplasias Colorretais/metabolismo , Inflamação/genética , Inflamação/metabolismo , Lectinas/genética , Lectinas/metabolismo , Lectinas Semelhantes a Imunoglobulina de Ligação ao Ácido Siálico/genética , Lectinas Semelhantes a Imunoglobulina de Ligação ao Ácido Siálico/metabolismo , Camundongos KnockoutRESUMO
Despite advances in artificial intelligence (AI), target-based drug development remains a costly, complex and imprecise process. We introduce F.O.R.W.A.R.D [ Framework for Outcome-based Research and Drug Development ], a network-based target prioritization approach and test its utility in the challenging therapeutic area of Inflammatory Bowel Diseases (IBD), which is a chronic condition of multifactorial origin. F.O.R.W.A.R.D leverages real-world outcomes, using a machine-learning classifier trained on transcriptomic data from seven prospective randomized clinical trials involving four drugs. It establishes a molecular signature of remission as the therapeutic goal and computes, by integrating principles of network connectivity, the likelihood that a drug's action on its target(s) will induce the remission-associated genes. Benchmarking F.O.R.W.A.R.D against 210 completed clinical trials on 52 targets showed a perfect predictive accuracy of 100%. The success of F.O.R.W.A.R.D was achieved despite differences in targets, mechanisms, and trial designs. F.O.R.W.A.R.D-driven in-silico phase '0' trials revealed its potential to inform trial design, justify re-trialing failed drugs, and guide early terminations. With its extendable applications to other therapeutic areas and its iterative refinement with emerging trials, F.O.R.W.A.R.D holds the promise to transform drug discovery by generating foresight from hindsight and impacting research and development as well as human-in-the-loop clinical decision-making.
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A long-standing question in the field of signal transduction is how distinct signaling pathways interact with each other to control cell behavior. Growth factor receptors and G protein-coupled receptors (GPCRs) are the two major signaling hubs in eukaryotes. Given that the mechanisms by which they signal independently have been extensively characterized, we investigated how they may cross-talk with each other. Using linear ion trap mass spectrometry and cell-based biophysical, biochemical, and phenotypic assays, we found at least three distinct ways in which epidermal growth factor affected canonical G protein signaling by the Gi-coupled GPCR CXCR4 through the phosphorylation of Gαi. Phosphomimicking mutations in two residues in the αE helix of Gαi (tyrosine-154/tyrosine-155) suppressed agonist-induced Gαi activation while promoting constitutive Gßγ signaling. Phosphomimicking mutations in the P loop (serine-44, serine-47, and threonine-48) suppressed Gi activation entirely, thus completely segregating growth factor and GPCR pathways. As expected, most of the phosphorylation events appeared to affect intrinsic properties of Gαi proteins, including conformational stability, nucleotide binding, and the ability to associate with and to release Gßγ. However, one phosphomimicking mutation, targeting the carboxyl-terminal residue tyrosine-320, promoted mislocalization of Gαi from the plasma membrane, a previously uncharacterized mechanism of suppressing GPCR signaling through G protein subcellular compartmentalization. Together, these findings elucidate not only how growth factor and chemokine signals cross-talk through the phosphorylation-dependent modulation of Gαi but also how such cross-talk may generate signal diversity.
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Subunidades alfa Gi-Go de Proteínas de Ligação ao GTP , Receptores CXCR4 , Transdução de Sinais , Fosforilação , Humanos , Células HEK293 , Subunidades alfa Gi-Go de Proteínas de Ligação ao GTP/metabolismo , Subunidades alfa Gi-Go de Proteínas de Ligação ao GTP/genética , Subunidades alfa Gi-Go de Proteínas de Ligação ao GTP/química , Receptores CXCR4/metabolismo , Receptores CXCR4/genética , Fator de Crescimento Epidérmico/metabolismo , Fator de Crescimento Epidérmico/genética , Receptores Acoplados a Proteínas G/metabolismo , Receptores Acoplados a Proteínas G/genética , AnimaisRESUMO
Cancer stem cells (CSCs) are mainly responsible for tumorigenesis, chemoresistance, and cancer recurrence. CSCs growth and progression are regulated by multiple signaling cascades including Wnt/ß-catenin and Hh/GLI-1, which acts independently or via crosstalk. Targeting the crosstalk of signaling pathways would be an effective approach to control the CSC population. Both Wnt/ß-catenin and Hh/GLI-1 signaling cascades are known to be regulated by p53/p21-dependent mechanism. However, it is interesting to delineate whether p21 can induce apoptosis in a p53-independent manner. Therefore, utilizing various subtypes of oral CSCs (SCC9-PEMT p53+/+p21+/+, SCC9-PEMT p53-/-p21+/+, SCC9-PEMT p53+/+p21-/- and SCC9-PEMT p53-/-p21-/-), we have examined the distinct roles of p53 and p21 in Resveratrol nanoparticle (Res-Nano)-mediated apoptosis. It is interesting to see that, besides the p53/p21-mediated mechanism, Res-Nano exposure also significantly induced apoptosis in oral CSCs through a p53-independent activation of p21. Additionally, Res-Nano-induced p21-activation deregulated the ß-catenin-GLI-1 complex and consequently reduced the TCF/LEF and GLI-1 reporter activities. In agreement with in vitro data, similar experimental results were obtained in in vivo mice xenograft model.
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Apoptose , Inibidor de Quinase Dependente de Ciclina p21 , Neoplasias Bucais , Nanopartículas , Células-Tronco Neoplásicas , Resveratrol , Proteína Supressora de Tumor p53 , Proteína GLI1 em Dedos de Zinco , beta Catenina , Apoptose/efeitos dos fármacos , Células-Tronco Neoplásicas/efeitos dos fármacos , Células-Tronco Neoplásicas/metabolismo , Células-Tronco Neoplásicas/patologia , Resveratrol/farmacologia , Proteína GLI1 em Dedos de Zinco/metabolismo , Proteína GLI1 em Dedos de Zinco/genética , beta Catenina/metabolismo , Proteína Supressora de Tumor p53/metabolismo , Humanos , Neoplasias Bucais/patologia , Neoplasias Bucais/tratamento farmacológico , Neoplasias Bucais/metabolismo , Animais , Inibidor de Quinase Dependente de Ciclina p21/metabolismo , Inibidor de Quinase Dependente de Ciclina p21/genética , Camundongos , Linhagem Celular Tumoral , Ensaios Antitumorais Modelo de XenoenxertoRESUMO
BACKGROUND: Anti-MDA5 (Melanoma differentiation-associated protein-5) positive dermatomyositis (MDA5+-DM) is characterised by rapidly progressive interstitial lung disease (ILD) and high mortality. MDA5 is an RNA sensor and a key pattern recognition receptor for the SARS-CoV-2 virus. METHODS: This is a retrospective observational study of a surge in MDA5 autoimmunity, as determined using a 15 muscle-specific autoantibodies (MSAs) panel, between Janurary 2018 and December 2022 in Yorkshire, UK. MDA5-positivity was correlated with clinical features and outcome, and regional SARS-CoV-2 positivity and vaccination rates. Gene expression patterns in COVID-19 were compared with autoimmune lung disease and idiopathic pulmonary fibrosis (IPF) to gain clues into the genesis of the observed MDA5+-DM outbreak. FINDINGS: Sixty new anti-MDA5+, but not other MSAs surged between 2020 and 2022, increasing from 0.4% in 2019 to 2.1% (2020), 4.8% (2021) and 1.7% (2022). Few (8/60) had a prior history of confirmed COVID-19, peak rates overlapped with regional SARS-COV-2 community positivity rates in 2021, and 58% (35/60) had received anti-SARS-CoV-2 vaccines. 25/60 cases developed ILD which rapidly progression with death in 8 cases. Among the 35/60 non-ILD cases, 14 had myositis, 17 Raynaud phenomena and 10 had dermatomyositis spectrum rashes. Transcriptomic studies showed strong IFIH1 (gene encoding for MDA5) induction in COVID-19 and autoimmune-ILD, but not IPF, and IFIH1 strongly correlated with an IL-15-centric type-1 interferon response and an activated CD8+ T cell signature that is an immunologic hallmark of progressive ILD in the setting of systemic autoimmune rheumatic diseases. The IFIH1 rs1990760TT variant blunted such response. INTERPRETATION: A distinct pattern of MDA5-autoimmunity cases surged contemporaneously with circulation of the SARS-COV-2 virus during COVID-19. Bioinformatic insights suggest a shared immunopathology with known autoimmune lung disease mechanisms. FUNDING: This work was supported in part by the National Institute for Health Research (NIHR) Leeds Biomedical Research Centre (BRC), and in part by the National Institutes of Health (NIH) grant R01-AI155696 and pilot awards from the UC Office of the President (UCOP)-RGPO (R00RG2628, R00RG2642 and R01RG3780) to P.G. S.S was supported in part by R01-AI141630 (to P.G) and in part through funds from the American Association of Immunologists (AAI) Intersect Fellowship Program for Computational Scientists and Immunologists.
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Autoanticorpos , Autoimunidade , COVID-19 , Helicase IFIH1 Induzida por Interferon , Doenças Pulmonares Intersticiais , SARS-CoV-2 , Humanos , COVID-19/imunologia , Helicase IFIH1 Induzida por Interferon/genética , Helicase IFIH1 Induzida por Interferon/imunologia , Doenças Pulmonares Intersticiais/imunologia , Doenças Pulmonares Intersticiais/genética , SARS-CoV-2/imunologia , Masculino , Feminino , Pessoa de Meia-Idade , Autoanticorpos/imunologia , Idoso , Estudos Retrospectivos , Pandemias , Dermatomiosite/imunologia , Dermatomiosite/genética , AdultoRESUMO
Cancer stem cells (CSCs) have emerged as prime players in the intricate landscape of cancer development, progression, and resistance to traditional treatments. These unique cellular subpopulations own the remarkable capability of self-renewal and differentiation, giving rise to the diverse cellular makeup of tumors and fostering their recurrence following conventional therapies. In the quest for developing more effective cancer therapeutics, the focus has now shifted toward targeting the signaling pathways that govern CSCs behavior. This chapter underscores the significance of these signaling pathways in CSC biology and their potential as pivotal targets for the development of novel chemotherapy approaches. We delve into several key signaling pathways essential for maintaining the defining characteristics of CSCs, including the Wnt, Hedgehog, Notch, JAK-STAT, NF-κB pathways, among others, shedding light on their potential crosstalk. Furthermore, we highlight the latest advancements in CSC-targeted therapies, spanning from promising preclinical models to ongoing clinical trials. A comprehensive understanding of the intricate molecular aspects of CSC signaling pathways and their manipulation holds the prospective to revolutionize cancer treatment paradigms. This, in turn, could lead to more efficacious and personalized therapies with the ultimate goal of eradicating CSCs and enhancing overall patient outcomes. The exploration of CSC signaling pathways represents a key step towards a brighter future in the battle against cancer.
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Neoplasias , Células-Tronco Neoplásicas , Transdução de Sinais , Células-Tronco Neoplásicas/metabolismo , Células-Tronco Neoplásicas/patologia , Humanos , Transdução de Sinais/efeitos dos fármacos , Animais , Neoplasias/metabolismo , Neoplasias/tratamento farmacológico , Neoplasias/patologia , Antineoplásicos/farmacologia , Terapia de Alvo MolecularRESUMO
Eukaryotic cells learn and adapt via unknown network architectures. Recent work demonstrated a circuit of two GTPases used by cells to overcome growth factor scarcity, encouraging our view that artificial and biological intelligence share strikingly similar design principles and that cells function as deep reinforcement learning (RL) agents in uncertain environments.
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GTP Fosfo-Hidrolases , Transdução de Sinais , GTP Fosfo-Hidrolases/metabolismoRESUMO
Self-sufficiency (autonomy) in growth signaling, the earliest recognized hallmark of cancer, is fueled by the tumor cell's ability to "secrete-and-sense" growth factors (GFs); this translates into cell survival and proliferation that is self-sustained by autocrine/paracrine secretion. A Golgi-localized circuitry comprised of two GTPase switches has recently been implicated in the orchestration of growth signaling autonomy. Using breast cancer cells that are either endowed or impaired (by gene editing) in their ability to assemble the circuitry for growth signaling autonomy, here we define the transcriptome, proteome, and phenome of such an autonomous state, and unravel its role during cancer progression. We show that autonomy is associated with enhanced molecular programs for stemness, proliferation, and epithelial-mesenchymal plasticity. Autonomy is both necessary and sufficient for anchorage-independent GF-restricted proliferation and resistance to anticancer drugs and is required for metastatic progression. Transcriptomic and proteomic studies show that autonomy is associated, with a surprising degree of specificity, with self-sustained epidermal growth factor receptor (EGFR)/ErbB signaling. Derivation of a gene expression signature for autonomy revealed that growth signaling autonomy is uniquely induced in circulating tumor cells (CTCs), the harshest phase in the life of tumor cells when it is deprived of biologically available epidermal growth factor (EGF). We also show that autonomy in CTCs tracks therapeutic response and prognosticates outcome. These data support a role for growth signaling autonomy in multiple processes essential for the blood-borne dissemination of human breast cancer.
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Recently, we reported that a combination of a natural, bioactive compound Resveratrol (RES) and a PARP inhibitor Olaparib (OLA) deregulated the homologous recombination (HR) pathway, and enhanced apoptosis in BRCA1-wild-type, HR-proficient breast cancer cells. Upon DNA damage, chromatin relaxation takes place, which allows the DNA repair proteins to access the DNA lesion. But whether chromatin remodeling has any role in RES + OLA-mediated HR inhibition is not known. By using in vitro and ex vivo model systems of breast cancer, we have investigated whether RES + OLA inhibits chromatin relaxation and thereby blocks the HR pathway. It was found that RES + OLA inhibited PARP1 activity, terminated PARP1-BRCA1 interaction, and deregulated the HR pathway only in the chromatin fraction of MCF-7 cells. DR-GFP reporter plasmid-based HR assay demonstrated marked reduction in HR efficiency in I-SceI endonuclease-transfected cells treated with OLA. RES + OLA efficiently trapped PARP1 at the DNA damage site in the chromatin of MCF-7 cells. Unaltered expressions of HR proteins were found in the chromatin of PARP1-silenced MCF-7 cells, which confirmed that RES + OLA-mediated DNA damage response was PARP1-dependent. Histone Acetyltransferase (HAT) activity and histone H4 acetylation assays showed reduction in HAT activity and H4 acetylation in RES + OLA-treated chromatin fraction of cells. Western blot analysis showed that the HAT enzyme TIP60, P400 and acetylated H4 were downregulated after RES + OLA exposure. In the co-immunoprecipitation assay, it was observed that RES + OLA caused abolition of PARP1-TIP60-BRCA1 interaction, which suggested the PARP1-dependent TIP60-BRCA1 association. Unaltered expressions of PAR, BRCA1, P400, and acetylated H4 in the chromatin of TIP60-silenced MCF-7 cells further confirmed the role of TIP60 in PARP1-mediated HR activation in the chromatin. Similar results were obtained in ex vivo patient-derived primary breast cancer cells. Thus, the present study revealed that RES + OLA treatment inhibited PARP1 activity in the chromatin, and blocked TIP60-mediated chromatin relaxation, which, in turn, affected PARP1-dependent TIP60-BRCA1 association, resulting in deregulation of HR pathway in breast cancer cells.
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Antineoplásicos , Neoplasias da Mama , Humanos , Feminino , Cromatina , Inibidores de Poli(ADP-Ribose) Polimerases/farmacologia , Resveratrol/farmacologia , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/genética , Reparo de DNA por RecombinaçãoRESUMO
Tumor associated macrophages (TAMs) and cancer-associated fibroblasts (CAFs) in the tumor microenvironment secrete several cytokines, which involved in tumor initiation, progression, metastatic outgrowth and angiogenesis. However, the association between TAMs and CAFs in the context of tumor development remain unclear. Here, we studied the relationship between TAMs and CAFs along with the involvement of cytokines in the production of cancer-stem-like-cells (CSCs) in oral cancer cells and explored the potential anticancer effects of Nano-formulated Resveratrol (Res-NP) using an activated macrophage-M1 (AM-M1) and activated fibroblast cells as the model system. IL-6 secretion was found to be enhanced in the conditioned-medium (CM) when AM-M1 cells + CAFs-like cells were cocultured together. CSCs-enriched population was developed after addition of CM of AM-M1 +CAFs in H-357 cells and patient-derived-primary-oral-cancer cells. AM-M1 cells+ CAFs-like cells secreted IL-6 enhanced CSCs growth, proliferation, metastasis, and angiogenesis. IL-6 was found to promote PD-L1 expression in CSCs-enriched cells via JAK2/STAT3 pathway, as evident from the enhanced expression of p-JAK2 and p-STAT3. Nevertheless, Res-NP inhibited CSCs proliferation and reduced the expression of metastatic and angiogenic markers, in ovo blood vascularization, NO production and MMPs expression. Res-NP delinked the association between AM-M1 and CAFs by blocking IL-6 production and also disrupted the potential connection between IL-6 and PD-L1 with considerable decrease in p-JAK2 and p-STAT3 expressions. IL-6 depletion inhibited stemness and angiogenesis in oral CSCs by downregulating PD-L1 via JAK2/STAT3 cascade. Similar observations were also observed in Res-NP treated xenograft mice. Thus, data demonstrate that CSCs growth is dependent on IL-6/PD-L1 axis. Res-NP deregulates the association between AM-M1 and CAFs along-with attenuates carcinogenesis in in vitro, in ovo, ex vivo and in vivo model systems by inhibiting PD-L1 via IL-6/JAK2/STAT3 axis.
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Fibroblastos Associados a Câncer , Neoplasias Bucais , Humanos , Animais , Camundongos , Fibroblastos Associados a Câncer/metabolismo , Fibroblastos Associados a Câncer/patologia , Interleucina-6/metabolismo , Resveratrol/farmacologia , Macrófagos Associados a Tumor/metabolismo , Antígeno B7-H1/metabolismo , Linhagem Celular Tumoral , Neoplasias Bucais/metabolismo , Microambiente Tumoral , Janus Quinase 2/metabolismo , Fator de Transcrição STAT3/metabolismoRESUMO
Aim: This study aimed to determine if quinacrine-gold hybrid nanoparticles (QAuNPs) + near-infrared (NIR) deregulate HSP-70/P300 complex-mediated H3K14 acetylation in estrogen receptor/progesterone receptor (ER/PR+) breast cancer stem cells (CSCs). Materials & methods: Various cells and mouse-based systems were used as models. Results: QAuNP + NIR treatment reduced the nuclear translocation of HSP-70, affected the histone acetyltransferase activity of P300 and specifically decreased H3K14 acetylation in ER/PR+ breast CSCs. Finally, HSP-70 knockdown showed a reduction in P300 histone acetyltransferase activity, decreased H3K14 acetylation and inhibited activation of the TGF-ß gene. Conclusion: This study revealed that QAuNP + NIR irradiation inhibits oncogenic activation of the TGF-ß gene by decreasing H3K14 acetylation mediated through the HSP-70/P300 nuclear complex in ER/PR+ breast CSCs.
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Nanopartículas , Neoplasias , Animais , Camundongos , Acetilação , Ouro , Histona Acetiltransferases , Células-Tronco Neoplásicas , Quinacrina/farmacologia , Fator de Crescimento Transformador beta , Humanos , FemininoRESUMO
BACKGROUND: Although differentiation therapy can cure some hematologic malignancies, its curative potential remains unrealized in solid tumors. This is because conventional computational approaches succumb to the thunderous noise of inter-/intratumoral heterogeneity. Using colorectal cancers (CRCs) as an example, here we outline a machine learning(ML)-based approach to track, differentiate, and selectively target cancer stem cells (CSCs). METHODS: A transcriptomic network was built and validated using healthy colon and CRC tissues in diverse gene expression datasets (~5,000 human and >300 mouse samples). Therapeutic targets and perturbation strategies were prioritized using ML, with the goal of reinstating the expression of a transcriptional identifier of the differentiated colonocyte, CDX2, whose loss in poorly differentiated (CSC-enriched) CRCs doubles the risk of relapse/death. The top candidate target was then engaged with a clinical-grade drug and tested on 3 models: CRC lines in vitro, xenografts in mice, and in a prospective cohort of healthy (n = 3) and CRC (n = 23) patient-derived organoids (PDOs). RESULTS: The drug shifts the network predictably, induces CDX2 and crypt differentiation, and shows cytotoxicity in all 3 models, with a high degree of selectivity towards all CDX2-negative cell lines, xenotransplants, and PDOs. The potential for effective pairing of therapeutic efficacy (IC50) and biomarker (CDX2-low state) is confirmed in PDOs using multivariate analyses. A 50-gene signature of therapeutic response is derived and tested on 9 independent cohorts (~1700 CRCs), revealing the impact of CDX2-reinstatement therapy could translate into a ~50% reduction in the risk of mortality/recurrence. CONCLUSIONS: Findings not only validate the precision of the ML approach in targeting CSCs, and objectively assess its impact on clinical outcome, but also exemplify the use of ML in yielding clinical directive information for enhancing personalized medicine.
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Background: Anti-MDA5 (Melanoma differentiation-associated protein-5) positive dermatomyositis (MDA5 + -DM) is characterised by rapidly progressive interstitial lung disease (ILD) and high mortality. MDA5 senses single-stranded RNA and is a key pattern recognition receptor for the SARS-CoV-2 virus. Methods: This is a retrospective observational study of a surge in MDA5 autoimmunity, as determined using a 15 muscle-specific autoantibodies (MSAs) panel, between Janurary 2018-December 2022 in Yorkshire, UK. MDA5-positivity was correlated with clinical features and outcome, and regional SARS-CoV-2 positivity and vaccination rates. Gene expression patterns in COVID-19 were compared with autoimmune lung disease and idiopathic pulmonary fibrosis (IPF) to gain clues into the genesis of the observed MDA5 + -DM outbreak. Results: Sixty new anti-MDA5+, but not other MSAs surged between 2020-2022, increasing from 0.4% in 2019 to 2.1% (2020), 4.8% (2021) and 1.7% (2022). Few (8/60) had a prior history of confirmed COVID-19, peak rates overlapped with regional SARS-COV-2 community positivity rates in 2021, and 58% (35/60) had received anti-SARS-CoV-2 RNA vaccines. Few (8/60) had a prior history of COVID-19, whereas 58% (35/60) had received anti-SARS-CoV-2 RNA vaccines. 25/60 cases developed ILD which rapidly progression with death in 8 cases. Among the 35/60 non-ILD cases, 14 had myositis, 17 Raynaud phenomena and 10 had dermatomyositis spectrum rashes. Transcriptomic studies showed strong IFIH1 (gene encoding for MDA5) induction in COVID-19 and autoimmune-ILD, but not IPF, and IFIH1 strongly correlated with an IL-15-centric type-1 interferon response and an activated CD8+ T cell signature that is an immunologic hallmark of progressive ILD in the setting of systemic autoimmune rheumatic diseases. The IFIH1 rs1990760TT variant blunted such response. Conclusions: A distinct pattern of MDA5-autoimmunity cases surged contemporaneously with circulation of the SARS-COV-2 virus during COVID-19. Bioinformatic insights suggest a shared immunopathology with known autoimmune lung disease mechanisms.
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The presence of cancer stem cells (CSCs) in the tumor microenvironment (TME) is majorly responsible for the development and recurrence of cancer. Earlier reports suggested that upon DNA damage, poly-(ADP-ribose) polymerase-1 (PARP-1) helps in chromatin modulation and DNA repair process, thereby promoting CSC survival. But whether a combination of DNA damaging agents along with PARP inhibitors can modulate chromatin assembly, inhibit DNA repair processes, and subsequently target CSCs is not known. Hence, we have investigated the effect of nontoxic bioactive compound quinacrine (QC) and a potent PARP inhibitor Talazoparib in patient-derived oral mucosa CSCs (OM-CSCs) and in vivo xenograft mice preclinical model systems. Data showed that QC + Talazoparib inhibited the PARP-1-mediated chromatin remodelers' recruitment and deregulated HAT activity of GCN5 (general control nonderepressible-5) and P300 at DNA damage site, thereby preventing the access of repair proteins to the damaged DNA. Additionally, this combination treatment inhibited topoisomerase activity, induced topological stress, and induced apoptosis in OM-CSCs. Similar results were observed in an in vivo xenograft mice model system. Collectively, the data suggested that QC + Talazoparib treatment inhibited BER pathway, induced genomic instability and triggered apoptosis in OM-CSCs through the deregulation of PARP-1-mediated chromatin remodelers (GCN5 and P300) activity. Schematic representation of QC + Talazoparib-induced apoptosis in oral mucosa CSCs. (1) Induction of DNA damage takes place after QC treatment (2) PARP1-mediated PARylation at the site of DNA damage, which recruits multiple chromatin remodelers (3) Acetylation at the histone tails relax the structure of chromatin and recruits the BER pathway proteins at the site of DNA damage. (4) BER pathway activated at the site of DNA damage. (5) CSCs survive after successful repair of DNA damage. (6) Treatment of QC-treated CSCs with PARP inhibitor Talazoparib (7) Inhibition of PARylation results in failure of chromatin remodelers to interact with PARP1. (8) Inhibition of acetylation status leads to chromatin compaction. (9) BER pathway proteins are not recruited at the site of DNA damage, resulting in inhibition of BER pathway and accumulation of unrepaired DNA damage, leading to apoptosis and cell death.
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Antineoplásicos , Quinacrina , Humanos , Animais , Camundongos , Quinacrina/farmacologia , Inibidores de Poli(ADP-Ribose) Polimerases/farmacologia , Mucosa Bucal , Reparo do DNA , Antineoplásicos/farmacologia , Poli(ADP-Ribose) Polimerase-1/metabolismo , Dano ao DNA , Cromatina , DNA/farmacologia , ApoptoseRESUMO
OBJECTIVE: Sensitization of mismatch repair (MMR)-deficient colorectal cancer (CRC) cells by 5-Fluorouracil (5-FU) is well-documented. But not much is known about the treatment of MMR-proficient CRC cancer stem cells (CRC-CSCs). Here, we investigated whether a PARP inhibitor (ABT-888) can enhance the 5-FU-mediated apoptosis in CRC-CSCs through MMR pathway inhibition. METHODS: The anti-cancer action of 5-FU+ABT-888 combination in CRC-CSCs has been studied by using in vitro, ex vivo, and in vivo preclinical model systems. RESULTS: 5-FU caused DNA damage in CRC-CSCs, and ABT-888 enhanced the accumulation of DNA mismatches by downregulating the MMR pathway, triggering S-phase arrest, and finally apoptosis and cell death in 5-FU-pre-treated MMR-proficient-CRC-CSCs at much lower concentrations than their individual treatments. After 5-FU treatment, PARylated-PARP1 activated MMR pathway by interacting with MSH6. But, upon ABT-888 treatment in 5-FU-pre-exposed CSCs, PARylation was inhibited, as a result of which PARP1 could not interact with MSH6, and other MMR proteins were downregulated. The role of MSH6 in PARP1-mediated MMR activation, was confirmed by silencing MSH6 gene, which resulted in MMR pathway shutdown. Similar results were obtained in ex vivo and in vivo model systems. CONCLUSIONS: 5-FU+ABT-888 combination enhanced CRC-CSCs death by increasing DNA damage accumulation and simultaneously inhibiting the MMR pathway in MMR-proficient cells. But this study does not discuss whether the combination treatment will increase the sensitivity of MMR-deficient CSCs, for which further research will be performed in the future.
5-FU is a well-known drug commonly used to treat colorectal cancer and it causes DNA damage inside the cancer cells. The limitation of 5-FU treatment is the development of chemoresistance due to the high DNA repair capacity of cancer stem cells present in the tumor microenvironment. In this study, a novel chemotherapeutic approach has been developed to target colorectal cancer stem cells by using a combination of 5-FU and a PARP1 inhibitor (ABT-888). Here, 5-FU caused DNA damage and ABT-888 enhanced the accumulation of the DNA lesions by inhibiting the MMR repair pathway in 5-FU-pre-treated MMR-proficient-CRC-CSCs. This resulted in S-phase arrest, induction of apoptosis, and finally CSCs death.
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Antineoplásicos , Neoplasias Colorretais , Humanos , Fluoruracila/farmacologia , Fluoruracila/uso terapêutico , Inibidores de Poli(ADP-Ribose) Polimerases/farmacologia , Antineoplásicos/farmacologia , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/genética , Proteínas de Ligação a DNA , Células-Tronco NeoplásicasRESUMO
Macrophages clear infections by engulfing and digesting pathogens within phagolysosomes. Pathogens escape this fate by engaging in a molecular arms race; they use WxxxE motif-containing "effector" proteins to subvert the host cells they invade and seek refuge within protective vacuoles. Here, we define the host component of the molecular arms race as an evolutionarily conserved polar "hot spot" on the PH domain of ELMO1 (Engulfment and Cell Motility protein 1), which is targeted by diverse WxxxE effectors. Using homology modeling and site-directed mutagenesis, we show that a lysine triad within the "patch" directly binds all WxxxE effectors tested: SifA (Salmonella), IpgB1 and IpgB2 (Shigella), and Map (enteropathogenic Escherichia coli). Using an integrated SifA-host protein-protein interaction network, in silico network perturbation, and functional studies, we show that the major consequences of preventing SifA-ELMO1 interaction are reduced Rac1 activity and microbial invasion. That multiple effectors of diverse structure, function, and sequence bind the same hot spot on ELMO1 suggests that the WxxxE effector(s)-ELMO1 interface is a convergence point of intrusion detection and/or host vulnerability. We conclude that the interface may represent the fault line in coevolved molecular adaptations between pathogens and the host, and its disruption may serve as a therapeutic strategy.
Assuntos
Proteínas de Bactérias , Enterobacteriaceae , Macrófagos , Proteínas de Bactérias/metabolismo , Sequência de Bases , Salmonella/metabolismo , Humanos , Animais , Interações Hospedeiro-Patógeno , Enterobacteriaceae/classificação , Enterobacteriaceae/fisiologia , Infecções por Enterobacteriaceae/microbiologia , Macrófagos/microbiologiaRESUMO
PRMT5 is a type II arginine methyltransferase abundantly expressed in the colonic epithelium. It is up-regulated in inflammatory bowel disease and colorectal cancer. However, its role in mucosal defense against enteric infection has not been studied. Here, we report that Prmt5 in the murine colon is up-regulated in response to Citrobacter rodentium infection. Pathogen clearance in mice with haploinsufficient expression of Prmt5 is significantly delayed compared with wildtype littermate controls. Transcriptomic analyses further reveal that PRMT5 regulates the expression of canonical crypt goblet cell genes involved in mucus production, assembly, and anti-microbial responses via methyltransferase activity-dependent and -independent mechanisms. Together, these findings uncover PRMT5 as a novel regulator of mucosal defense and a potential therapeutic target for treating intestinal diseases.
Assuntos
Infecções por Enterobacteriaceae , Intestinos , Animais , Camundongos , Peptídeos e Proteínas de Sinalização Intracelular , Proteína-Arginina N-Metiltransferases/genética , Colo , Infecções por Enterobacteriaceae/genéticaRESUMO
BACKGROUND: Single-cell transcriptomic studies have greatly improved organ-specific insights into macrophage polarization states are essential for the initiation and resolution of inflammation in all tissues; however, such insights are yet to translate into therapies that can predictably alter macrophage fate. METHOD: Using machine learning algorithms on human macrophages, here we reveal the continuum of polarization states that is shared across diverse contexts. A path, comprised of 338 genes accurately identified both physiologic and pathologic spectra of "reactivity" and "tolerance", and remained relevant across tissues, organs, species, and immune cells (>12,500 diverse datasets). FINDINGS: This 338-gene signature identified macrophage polarization states at single-cell resolution, in physiology and across diverse human diseases, and in murine pre-clinical disease models. The signature consistently outperformed conventional signatures in the degree of transcriptome-proteome overlap, and in detecting disease states; it also prognosticated outcomes across diverse acute and chronic diseases, e.g., sepsis, liver fibrosis, aging, and cancers. Crowd-sourced genetic and pharmacologic studies confirmed that model-rationalized interventions trigger predictable macrophage fates. INTERPRETATION: These findings provide a formal and universally relevant definition of macrophage states and a predictive framework (http://hegemon.ucsd.edu/SMaRT) for the scientific community to develop macrophage-targeted precision diagnostics and therapeutics. FUNDING: This work was supported by the National Institutes for Health (NIH) grant R01-AI155696 (to P.G, D.S and S.D). Other sources of support include: R01-GM138385 (to D.S), R01-AI141630 (to P.G), R01-DK107585 (to S.D), and UG3TR003355 (to D.S, S.D, and P.G). D.S was also supported by two Padres Pedal the Cause awards (Padres Pedal the Cause/RADY #PTC2017 and San Diego NCI Cancer Centers Council (C3) #PTC2017). S.S, G.D.K, and D.D were supported through The American Association of Immunologists (AAI) Intersect Fellowship Program for Computational Scientists and Immunologists. We also acknowledge support from the Padres Pedal the Cause #PTC2021 and the Torey Coast Foundation, La Jolla (P.G and D.S). D.S, P.G, and S.D were also supported by the Leona M. and Harry B. Helmsley Charitable Trust.
Assuntos
Macrófagos , Médicos , Humanos , Estados Unidos , Animais , Camundongos , InflamaçãoRESUMO
BACKGROUND: Breast cancer stem cells (BCSCs) have a critical role in progression of breast cancer by inducing angiogenesis. Several therapeutic strategies have been designed for the treatment of breast cancer by specifically preventing angiogenesis. But there is a dearth of study regarding the treatment procedure which can specifically target and kill the BCSCs and cause lesser harm to healthy cells of the body. A plant-based bioactive compound Quinacrine (QC) specifically kills cancer stem cells (CSCs) without harming healthy cells and also inhibits cancer angiogenesis but the detailed mechanistic study of its anti-CSCs and anti-angiogenic activity is yet to explore. HYPOTHESIS: Earlier report showed that both cMET and ABCG2 play an essential role in cancer angiogenesis. Both are present on the cell surface of CSCs and share an identical ATP-binding domain. Interestingly, QC a plant based and bioactive compound which was found to inhibit the function of CSCs marker cMET and ABCG2. These relevant evidence led us to hypothesize that cMET and ABCG2 may interact with each other and induce the production of angiogenic factors, resulting in activation of cancer angiogenesis and QC might disrupt the interaction between them to stop this phenomena. METHODS: Co-immunoprecipitation assay, immunofluorescence assay, and western blotting were performed by using ex vivo patient-derived breast cancer-stem-cells (PDBCSCs) and human umbilical vein endothelial cells (HUVECs). In silico study was carried out to check the interaction between cMET and ABCG2 in presence or absence of QC. Tube formation assay using HUVECs and in ovo Chorioallantoic membrane (CAM) assay using chick fertilized eggs were performed to monitor angiogenesis. In vivo patient-derived xenograft (PDX) mice model was used to validate in silico and ex vivo results. RESULTS: Data revealed that in a hypoxic tumor microenvironment (TME), cMET and ABCG2 interact with each other and upregulate HIF-1α/VEGF-A axis to induce breast cancer angiogenesis. In silico and ex vivo study showed that QC disrupted the interaction between cMET and ABCG2 to inhibit the angiogenic response in endothelial cells by reducing the secretion of VEGF-A from PDBCSCs within the TME. Knockdown of cMET, ABCG2 or both, significantly downregulated the expression of HIF-1α and reduced the secretion of pro-angiogenic factor VEGF-A in the TME of PDBCSCs. Additionally, when PDBCSCs were treated with QC, similar experimental results were obtained. CONCLUSION: In silico, in ovo, ex vivo and in vivo data confirmed that QC inhibited the HIF-1α/VEGF-A mediated angiogenesis in breast cancer by disrupting the interaction between cMET and ABCG2.