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1.
Cell Rep ; 43(5): 114240, 2024 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-38753486

RESUMO

Adipose tissue remodeling and dysfunction, characterized by elevated inflammation and insulin resistance, play a central role in obesity-related development of type 2 diabetes (T2D) and cardiovascular diseases. Long intergenic non-coding RNAs (lincRNAs) are important regulators of cellular functions. Here, we describe the functions of linc-ADAIN (adipose anti-inflammatory), an adipose lincRNA that is downregulated in white adipose tissue of obese humans. We demonstrate that linc-ADAIN knockdown (KD) increases KLF5 and interleukin-8 (IL-8) mRNA stability and translation by interacting with IGF2BP2. Upregulation of KLF5 and IL-8, via linc-ADAIN KD, leads to an enhanced adipogenic program and adipose tissue inflammation, mirroring the obese state, in vitro and in vivo. KD of linc-ADAIN in human adipose stromal cell (ASC) hTERT adipocytes implanted into mice increases adipocyte size and macrophage infiltration compared to implanted control adipocytes, mimicking hallmark features of obesity-induced adipose tissue remodeling. linc-ADAIN is an anti-inflammatory lincRNA that limits adipose tissue expansion and lipid storage.

2.
bioRxiv ; 2024 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-38559188

RESUMO

Systemic lupus erythematosus (SLE) is a highly heterogenous autoimmune disease that affects multiple organs, including the heart. The mechanisms by which myocardial injury develops in SLE, however, remain poorly understood. Here we engineered human cardiac tissues and cultured them with IgG fractions containing autoantibodies from SLE patients with and without myocardial involvement. We observed unique binding patterns of IgG from two patient subgroups: (i) patients with severe myocardial inflammation exhibited enhanced binding to apoptotic cells within cardiac tissues subjected to stress, and (ii) patients with systolic dysfunction exhibited enhanced binding to the surfaces of viable cardiomyocytes. Functional assays and RNA sequencing (RNA-seq) revealed that IgGs from patients with systolic dysfunction exerted direct effects on engineered tissues in the absence of immune cells, altering tissue cellular composition, respiration and calcium handling. Autoantibody target characterization by phage immunoprecipitation sequencing (PhIP-seq) confirmed distinctive IgG profiles between patient subgroups. By coupling IgG profiling with cell surface protein analyses, we identified four pathogenic autoantibody candidates that may directly alter the function of cells within the myocardium. Taken together, these observations provide insights into the cellular processes of myocardial injury in SLE that have the potential to improve patient risk stratification and inform the development of novel therapeutic strategies.

3.
Res Sq ; 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38645164

RESUMO

Biomarkers play a crucial role in advancing precision medicine by enabling more targeted and individualized approaches to diagnosis and treatment. Various biofluids, including serum, plasma, cerebrospinal fluid (CSF), saliva, tears, pancreatic cyst fluids, and urine, have been identified as rich sources of potential for the early detection of disease biomarkers in conditions such as cancer, cardiovascular diseases, and neurodegenerative disorders. The analysis of plasma and serum in proteomics research encounters challenges due to their high complexity and the wide dynamic range of protein abundance. These factors impede the sensitivity, coverage, and precision of protein detection when employing mass spectrometry, a widely utilized technology in discovery proteomics. Conventional approaches such as neat plasma workflow are inefficient in accurately quantifying low-abundant proteins, including those associated with tissue leakage, immune response molecules, interleukins, cytokines, and interferons. Moreover, the manual nature of the workflow poses a significant hurdle in conducting large cohort studies. In this study, our focus is on comparing workflows for plasma proteomic profiling to establish a methodology that is not only sensitive and reproducible but also applicable for large cohort studies in biomarker discovery. Our investigation revealed that the SeerProteographXT workflow outperforms other workflows in terms of plasma proteome depth, quantitative accuracy, and reproducibility while offering complete automation of sample preparation. Notably, SeerProteographXT demonstrates versatility by applying it to various types of biofluids. Additionally, the proteins quantified widely cover secretory proteins in peripheral blood, and the pathway analysis enriched with relevant components such as interleukins, tissue necrosis factors, chemokines, and B and T cell receptors provides valuable insights. These proteins, often challenging to quantify in complex biological samples, hold potential as early detection markers for various diseases, thereby contributing to the improvement of patient care quality.

4.
Sci Transl Med ; 16(744): eadd8273, 2024 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-38657023

RESUMO

Rotator cuff injuries result in more than 500,000 surgeries annually in the United States, many of which fail. These surgeries typically involve repair of the injured tendon and removal of the subacromial bursa, a synovial-like tissue that sits between the rotator cuff and the acromion. The subacromial bursa has been implicated in rotator cuff pathogenesis and healing. Using proteomic profiling of bursa samples from nine patients with rotator cuff injury, we show that the bursa responds to injury in the underlying tendon. In a rat model of supraspinatus tenotomy, we evaluated the bursa's effect on the injured supraspinatus tendon, the uninjured infraspinatus tendon, and the underlying humeral head. The bursa protected the intact infraspinatus tendon adjacent to the injured supraspinatus tendon by maintaining its mechanical properties and protected the underlying humeral head by maintaining bone morphometry. The bursa promoted an inflammatory response in injured rat tendon, initiating expression of genes associated with wound healing, including Cox2 and Il6. These results were confirmed in rat bursa organ cultures. To evaluate the potential of the bursa as a therapeutic target, polymer microspheres loaded with dexamethasone were delivered to the intact bursae of rats after tenotomy. Dexamethasone released from the bursa reduced Il1b expression in injured rat supraspinatus tendon, suggesting that the bursa could be used for drug delivery to reduce inflammation in the healing tendon. Our findings indicate that the subacromial bursa contributes to healing in underlying tissues of the shoulder joint, suggesting that its removal during rotator cuff surgery should be reconsidered.


Assuntos
Bolsa Sinovial , Ratos Sprague-Dawley , Lesões do Manguito Rotador , Manguito Rotador , Tendões , Cicatrização , Animais , Lesões do Manguito Rotador/patologia , Lesões do Manguito Rotador/metabolismo , Lesões do Manguito Rotador/cirurgia , Humanos , Bolsa Sinovial/patologia , Bolsa Sinovial/metabolismo , Tendões/patologia , Tendões/metabolismo , Masculino , Manguito Rotador/patologia , Ratos , Dexametasona/farmacologia , Dexametasona/uso terapêutico , Feminino
5.
Stem Cell Res Ther ; 15(1): 104, 2024 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-38600587

RESUMO

BACKGROUND: Microglia, the brain's resident immune cells, play vital roles in brain development, and disorders like Alzheimer's disease (AD). Human iPSC-derived microglia (iMG) provide a promising model to study these processes. However, existing iMG generation protocols face challenges, such as prolonged differentiation time, lack of detailed characterization, and limited gene function investigation via CRISPR-Cas9. METHODS: Our integrated toolkit for in-vitro microglia functional genomics optimizes iPSC differentiation into iMG through a streamlined two-step, 20-day process, producing iMG with a normal karyotype. We confirmed the iMG's authenticity and quality through single-cell RNA sequencing, chromatin accessibility profiles (ATAC-Seq), proteomics and functional tests. The toolkit also incorporates a drug-dependent CRISPR-ON/OFF system for temporally controlled gene expression. Further, we facilitate the use of multi-omic data by providing online searchable platform that compares new iMG profiles to human primary microglia: https://sherlab.shinyapps.io/IPSC-derived-Microglia/ . RESULTS: Our method generates iMG that closely align with human primary microglia in terms of transcriptomic, proteomic, and chromatin accessibility profiles. Functionally, these iMG exhibit Ca2 + transients, cytokine driven migration, immune responses to inflammatory signals, and active phagocytosis of CNS related substrates including synaptosomes, amyloid beta and myelin. Significantly, the toolkit facilitates repeated iMG harvesting, essential for large-scale experiments like CRISPR-Cas9 screens. The standalone ATAC-Seq profiles of our iMG closely resemble primary microglia, positioning them as ideal tools to study AD-associated single nucleotide variants (SNV) especially in the genome regulatory regions. CONCLUSIONS: Our advanced two-step protocol rapidly and efficiently produces authentic iMG. With features like the CRISPR-ON/OFF system and a comprehensive multi-omic data platform, our toolkit equips researchers for robust microglial functional genomic studies. By facilitating detailed SNV investigation and offering a sustainable cell harvest mechanism, the toolkit heralds significant progress in neurodegenerative disease drug research and therapeutic advancement.


Assuntos
Doença de Alzheimer , Doenças Neurodegenerativas , Humanos , Microglia/metabolismo , Proteômica , Peptídeos beta-Amiloides , Genômica , Doença de Alzheimer/genética , Cromatina/genética , Cromatina/metabolismo
6.
PLoS Biol ; 22(3): e3002522, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38483887

RESUMO

Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) has affected approximately 800 million people since the start of the Coronavirus Disease 2019 (COVID-19) pandemic. Because of the high rate of mutagenesis in SARS-CoV-2, it is difficult to develop a sustainable approach for prevention and treatment. The Envelope (E) protein is highly conserved among human coronaviruses. Previous studies reported that SARS-CoV-1 E deficiency reduced viral propagation, suggesting that E inhibition might be an effective therapeutic strategy for SARS-CoV-2. Here, we report inhibitory peptides against SARS-CoV-2 E protein named iPep-SARS2-E. Leveraging E-induced alterations in proton homeostasis and NFAT/AP-1 pathway in mammalian cells, we developed screening platforms to design and optimize the peptides that bind and inhibit E protein. Using Vero-E6 cells, human-induced pluripotent stem cell-derived branching lung organoid and mouse models with SARS-CoV-2, we found that iPep-SARS2-E significantly inhibits virus egress and reduces viral cytotoxicity and propagation in vitro and in vivo. Furthermore, the peptide can be customizable for E protein of other human coronaviruses such as Middle East Respiratory Syndrome Coronavirus (MERS-CoV). The results indicate that E protein can be a potential therapeutic target for human coronaviruses.


Assuntos
COVID-19 , SARS-CoV-2 , Camundongos , Animais , Chlorocebus aethiops , Humanos , Linhagem Celular , Células Vero , Peptídeos/farmacologia , Mamíferos
7.
Cureus ; 16(2): e54770, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38524074

RESUMO

Background The creation of pneumoperitoneum is the first step in any laparoscopic surgery. There are various methods of creating pneumoperitoneum which can be divided into open or closed methods. The closed method involves the blind insertion of the Veress needle into the peritoneal cavity. The open technique involves making an incision and then dissecting the fascia to the peritoneal cavity to introduce the cannula under direct vision. This study was conducted to evaluate the safety and efficacy of open (Hasson's) and closed (Veress) techniques of intraperitoneal access for the creation of pneumoperitoneum in laparoscopic surgery. Material and methods The study was conducted in the Department of General Surgery, Vardhman Mahavir Medical College and Safdarjung Hospital, New Delhi. This was a prospective observational study and a total of 100 patients of laparoscopic surgeries fulfilling inclusion criteria were included in the study - 50 patients in group A undergoing the open method of creating pneumoperitoneum and 50 patients in group B undergoing the closed method of creating pneumoperitoneum were evaluated for the study period of 18 months from October 2020 through June 2022. Results The mean time to create pneumoperitoneum was 5.3 ± 1.41 minutes in the open method and 6.21 ± 1.36 minutes in the closed method. The mean time for umbilical port closure in our study was 7.33 ± 1.66 in the open group and 8.86 ± 2.19 in the closed group. In our study, there was no vascular or visceral injury noted in either of the methods used for the creation of pneumoperitoneum. Post-operative complications were almost equal in both the groups. Conclusions Both open and closed methods of intraperitoneal access are safe and effective for the creation of pneumoperitoneum during abdominal laparoscopy. The open method of creating pneumoperitoneum in laparoscopic surgery is a quicker method for the creation of pneumoperitoneum as compared to the closed method of intraperitoneal access.

8.
Cell ; 187(5): 1177-1190.e18, 2024 Feb 29.
Artigo em Inglês | MEDLINE | ID: mdl-38366593

RESUMO

Phospholipids containing a single polyunsaturated fatty acyl tail (PL-PUFA1s) are considered the driving force behind ferroptosis, whereas phospholipids with diacyl-PUFA tails (PL-PUFA2s) have been rarely characterized. Dietary lipids modulate ferroptosis, but the mechanisms governing lipid metabolism and ferroptosis sensitivity are not well understood. Our research revealed a significant accumulation of diacyl-PUFA phosphatidylcholines (PC-PUFA2s) following fatty acid or phospholipid treatments, correlating with cancer cell sensitivity to ferroptosis. Depletion of PC-PUFA2s occurred in aging and Huntington's disease brain tissue, linking it to ferroptosis. Notably, PC-PUFA2s interacted with the mitochondrial electron transport chain, generating reactive oxygen species (ROS) for initiating lipid peroxidation. Mitochondria-targeted antioxidants protected cells from PC-PUFA2-induced mitochondrial ROS (mtROS), lipid peroxidation, and cell death. These findings reveal a critical role for PC-PUFA2s in controlling mitochondria homeostasis and ferroptosis in various contexts and explain the ferroptosis-modulating mechanisms of free fatty acids. PC-PUFA2s may serve as diagnostic and therapeutic targets for modulating ferroptosis.


Assuntos
Gorduras na Dieta , Ferroptose , Fosfolipídeos , Ácidos Graxos , Fosfatidilcolinas , Fosfolipídeos/química , Fosfolipídeos/metabolismo , Espécies Reativas de Oxigênio , Gorduras na Dieta/metabolismo
9.
Science ; 383(6682): eadi5798, 2024 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-38301010

RESUMO

Increasing use of covalent and noncovalent inhibitors of Bruton's tyrosine kinase (BTK) has elucidated a series of acquired drug-resistant BTK mutations in patients with B cell malignancies. Here we identify inhibitor resistance mutations in BTK with distinct enzymatic activities, including some that impair BTK enzymatic activity while imparting novel protein-protein interactions that sustain B cell receptor (BCR) signaling. Furthermore, we describe a clinical-stage BTK and IKZF1/3 degrader, NX-2127, that can bind and proteasomally degrade each mutant BTK proteoform, resulting in potent blockade of BCR signaling. Treatment of chronic lymphocytic leukemia with NX-2127 achieves >80% degradation of BTK in patients and demonstrates proof-of-concept therapeutic benefit. These data reveal an oncogenic scaffold function of mutant BTK that confers resistance across clinically approved BTK inhibitors but is overcome by BTK degradation in patients.


Assuntos
Tirosina Quinase da Agamaglobulinemia , Resistencia a Medicamentos Antineoplásicos , Fator de Transcrição Ikaros , Leucemia Linfocítica Crônica de Células B , Inibidores de Proteínas Quinases , Proteólise , Humanos , Tirosina Quinase da Agamaglobulinemia/genética , Tirosina Quinase da Agamaglobulinemia/metabolismo , Fator de Transcrição Ikaros/metabolismo , Leucemia Linfocítica Crônica de Células B/tratamento farmacológico , Leucemia Linfocítica Crônica de Células B/genética , Mutação , Fosforilação , Inibidores de Proteínas Quinases/farmacologia , Inibidores de Proteínas Quinases/uso terapêutico , Transdução de Sinais , Proteólise/efeitos dos fármacos , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos
10.
J Cachexia Sarcopenia Muscle ; 15(2): 536-551, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38221511

RESUMO

BACKGROUND: Duchenne muscular dystrophy (DMD) is an X-linked disorder characterized by progressive muscle weakness due to the absence of functional dystrophin. DMD patients also develop dilated cardiomyopathy (DCM). We have previously shown that DMD (mdx) mice and a canine DMD model (GRMD) exhibit abnormal intracellular calcium (Ca2+) cycling related to early-stage pathological remodelling of the ryanodine receptor intracellular calcium release channel (RyR2) on the sarcoplasmic reticulum (SR) contributing to age-dependent DCM. METHODS: Here, we used hiPSC-CMs from DMD patients selected by Speckle-tracking echocardiography and canine DMD cardiac biopsies to assess key early-stage Duchenne DCM features. RESULTS: Dystrophin deficiency was associated with RyR2 remodelling and SR Ca2+ leak (RyR2 Po of 0.03 ± 0.01 for HC vs. 0.16 ± 0.01 for DMD, P < 0.01), which led to early-stage defects including senescence. We observed higher levels of senescence markers including p15 (2.03 ± 0.75 for HC vs. 13.67 ± 5.49 for DMD, P < 0.05) and p16 (1.86 ± 0.83 for HC vs. 10.71 ± 3.00 for DMD, P < 0.01) in DMD hiPSC-CMs and in the canine DMD model. The fibrosis was increased in DMD hiPSC-CMs. We observed cardiac hypocontractility in DMD hiPSC-CMs. Stabilizing RyR2 pharmacologically by S107 prevented most of these pathological features, including the rescue of the contraction amplitude (1.65 ± 0.06 µm for DMD vs. 2.26 ± 0.08 µm for DMD + S107, P < 0.01). These data were confirmed by proteomic analyses, in particular ECM remodelling and fibrosis. CONCLUSIONS: We identified key cellular damages that are established earlier than cardiac clinical pathology in DMD patients, with major perturbation of the cardiac ECC. Our results demonstrated that cardiac fibrosis and premature senescence are induced by RyR2 mediated SR Ca2+ leak in DMD cardiomyocytes. We revealed that RyR2 is an early biomarker of DMD-associated cardiac damages in DMD patients. The progressive and later DCM onset could be linked with the RyR2-mediated increased fibrosis and premature senescence, eventually causing cell death and further cardiac fibrosis in a vicious cycle leading to further hypocontractility as a major feature of DCM. The present study provides a novel understanding of the pathophysiological mechanisms of the DMD-induced DCM. By targeting RyR2 channels, it provides a potential pharmacological treatment.


Assuntos
Cardiomiopatias , Cardiomiopatia Dilatada , Humanos , Camundongos , Animais , Cães , Cardiomiopatia Dilatada/etiologia , Distrofina/genética , Distrofina/metabolismo , Canal de Liberação de Cálcio do Receptor de Rianodina/genética , Canal de Liberação de Cálcio do Receptor de Rianodina/metabolismo , Camundongos Endogâmicos mdx , Cálcio/metabolismo , Proteômica , Miócitos Cardíacos/metabolismo , Miócitos Cardíacos/patologia , Fibrose
11.
Cell Chem Biol ; 31(2): 249-264.e7, 2024 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-37944523

RESUMO

Iron overload, characterized by accumulation of iron in tissues, induces a multiorgan toxicity whose mechanisms are not fully understood. Using cultured cell lines, Caenorhabditis elegans, and mice, we found that ferroptosis occurs in the context of iron-overload-mediated damage. Exogenous oleic acid protected against iron-overload-toxicity in cell culture and Caenorhabditis elegans by suppressing ferroptosis. In mice, oleic acid protected against FAC-induced liver lipid peroxidation and damage. Oleic acid changed the cellular lipid composition, characterized by decreased levels of polyunsaturated fatty acyl phospholipids and decreased levels of ether-linked phospholipids. The protective effect of oleic acid in cells was attenuated by GW6471 (PPAR-α antagonist), as well as in Caenorhabditis elegans lacking the nuclear hormone receptor NHR-49 (a PPAR-α functional homologue). These results highlight ferroptosis as a driver of iron-overload-mediated damage, which is inhibited by oleic acid. This monounsaturated fatty acid represents a potential therapeutic approach to mitigating organ damage in iron overload individuals.


Assuntos
Ferroptose , Sobrecarga de Ferro , Animais , Camundongos , Caenorhabditis elegans , Ácido Oleico/farmacologia , Receptores Ativados por Proliferador de Peroxissomo , Sobrecarga de Ferro/tratamento farmacológico , Ferro , Éteres Fosfolipídicos
12.
bioRxiv ; 2024 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-37214867

RESUMO

DNA interstrand crosslinks (ICLs) are covalent bonds between bases on opposing strands of the DNA helix which prevent DNA melting and subsequent DNA replication or RNA transcription. Here, we show that Ultraviolet Stimulated Scaffold Protein A (UVSSA) participates in transcription-coupled repair of ICLs in human cells. Inactivation of UVSSA sensitizes human cells to ICL-inducing drugs, and delays ICL repair. UVSSA is required for transcription-coupled repair of a single ICL in a fluorescence-based reporter assay. UVSSA localizes to chromatin following ICL damage, and interacts with transcribing Pol II, CSA, CSB, and TFIIH. Specifically, UVSSA interaction with TFIIH is required for ICL repair. Finally, UVSSA expression positively correlates with ICL chemotherapy resistance in human cancer cell lines. Our data strongly suggest that transcription-coupled ICL repair (TC-ICR) is a bona fide ICL repair mechanism that contributes to crosslinker drug resistance independently of replication-coupled ICL repair.

13.
J Neurosci ; 44(3)2024 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-38050142

RESUMO

ZCCHC17 is a putative master regulator of synaptic gene dysfunction in Alzheimer's disease (AD), and ZCCHC17 protein declines early in AD brain tissue, before significant gliosis or neuronal loss. Here, we investigate the function of ZCCHC17 and its role in AD pathogenesis using data from human autopsy tissue (consisting of males and females) and female human cell lines. Co-immunoprecipitation (co-IP) of ZCCHC17 followed by mass spectrometry analysis in human iPSC-derived neurons reveals that ZCCHC17's binding partners are enriched for RNA-splicing proteins. ZCCHC17 knockdown results in widespread RNA-splicing changes that significantly overlap with splicing changes found in AD brain tissue, with synaptic genes commonly affected. ZCCHC17 expression correlates with cognitive resilience in AD patients, and we uncover an APOE4-dependent negative correlation of ZCCHC17 expression with tangle burden. Furthermore, a majority of ZCCHC17 interactors also co-IP with known tau interactors, and we find a significant overlap between alternatively spliced genes in ZCCHC17 knockdown and tau overexpression neurons. These results demonstrate ZCCHC17's role in neuronal RNA processing and its interaction with pathology and cognitive resilience in AD, and suggest that the maintenance of ZCCHC17 function may be a therapeutic strategy for preserving cognitive function in the setting of AD pathology.


Assuntos
Doença de Alzheimer , Resiliência Psicológica , Feminino , Humanos , Masculino , Doença de Alzheimer/metabolismo , Cognição , Neurônios/metabolismo , RNA , Splicing de RNA/genética , Proteínas tau/metabolismo
14.
bioRxiv ; 2023 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-38116029

RESUMO

Polycomb Repressive Complex 2 (PRC2)-mediated histone H3K27 tri-methylation (H3K27me3) recruits canonical PRC1 (cPRC1) to maintain heterochromatin. In early development, polycomb-regulated genes are connected through long-range 3D interactions which resolve upon differentiation. Here, we report that polycomb looping is controlled by H3K27me3 spreading and regulates target gene silencing and cell fate specification. Using glioma-derived H3 Lys-27-Met (H3K27M) mutations as tools to restrict H3K27me3 deposition, we show that H3K27me3 confinement concentrates the chromatin pool of cPRC1, resulting in heightened 3D interactions mirroring chromatin architecture of pluripotency, and stringent gene repression that maintains cells in progenitor states to facilitate tumor development. Conversely, H3K27me3 spread in pluripotent stem cells, following neural differentiation or loss of the H3K36 methyltransferase NSD1, dilutes cPRC1 concentration and dissolves polycomb loops. These results identify the regulatory principles and disease implications of polycomb looping and nominate histone modification-guided distribution of reader complexes as an important mechanism for nuclear compartment organization. Highlights: The confinement of H3K27me3 at PRC2 nucleation sites without its spreading correlates with increased 3D chromatin interactions.The H3K27M oncohistone concentrates canonical PRC1 that anchors chromatin loop interactions in gliomas, silencing developmental programs.Stem and progenitor cells require factors promoting H3K27me3 confinement, including H3K36me2, to maintain cPRC1 loop architecture.The cPRC1-H3K27me3 interaction is a targetable driver of aberrant self-renewal in tumor cells.

15.
PNAS Nexus ; 2(11): pgad336, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37954156

RESUMO

In critical care patients, the ""temporary inactivity of the diaphragm caused by mechanical ventilation (MV) triggers a series of events leading to diaphragmatic dysfunction and atrophy, commonly known as ventilator-induced diaphragm dysfunction (VIDD). While mitochondrial dysfunction related to oxidative stress is recognized as a crucial factor in VIDD, the exact molecular mechanism remains poorly understood. In this study, we observe that 6 h of MV triggers aberrant mitochondrial dynamics, resulting in a reduction in mitochondrial size and interaction, associated with increased expression of dynamin-related protein 1 (DRP1). This effect can be prevented by P110, a molecule that inhibits the recruitment of DRP1 to the mitochondrial membrane. Furthermore, isolated mitochondria from the diaphragms of ventilated patients exhibited increased production of reactive oxygen species (ROS). These mitochondrial changes were associated with the rapid oxidation of type 1 ryanodine receptor (RyR1) and a decrease in the stabilizing subunit calstabin 1. Subsequently, we observed that the sarcoplasmic reticulum (SR) in the ventilated diaphragms showed increased calcium leakage and reduced contractile function. Importantly, the mitochondrial fission inhibitor P110 effectively prevented all of these alterations. Taken together, the results of our study illustrate that MV leads, in the diaphragm, to both mitochondrial fragmentation and dysfunction, linked to the up-/down-regulation of 320 proteins, as assessed through global comprehensive quantitative proteomics analysis, primarily associated with mitochondrial function. These outcomes underscore the significance of developing compounds aimed at modulating the balance between mitochondrial fission and fusion as potential interventions to mitigate VIDD in human patients.

16.
Cell Rep ; 42(11): 113198, 2023 11 28.
Artigo em Inglês | MEDLINE | ID: mdl-37865915

RESUMO

Cyclin-dependent kinase 4 and 6 inhibitors (CDK4/6i) are key therapeutic agents in the management of metastatic hormone-receptor-positive breast cancer. However, the emergence of drug resistance limits their long-term efficacy. Here, we show that breast cancer cells develop CDK4/6i resistance via a sequential two-step process of E2F activation. This process entails retinoblastoma (Rb)-protein degradation, followed by c-Myc-mediated amplification of E2F transcriptional activity. CDK4/6i treatment halts cell proliferation in an Rb-dependent manner but dramatically reduces Rb-protein levels. However, this reduction in Rb levels insufficiently induces E2F activity. To develop CDK4/6i resistance, upregulation or activating mutations in mitogenic or hormone signaling are required to stabilize c-Myc levels, thereby augmenting E2F activity. Our analysis of pre-treatment tumor samples reveals a strong correlation between c-Myc levels, rather than Rb levels, and poor therapeutic outcomes after CDK4/6i treatment. Moreover, we propose that proteasome inhibitors can potentially reverse CDK4/6i resistance by restoring Rb levels.


Assuntos
Neoplasias da Mama , Neoplasias da Retina , Retinoblastoma , Humanos , Feminino , Quinase 4 Dependente de Ciclina/metabolismo , Neoplasias da Mama/patologia , Quinase 6 Dependente de Ciclina/metabolismo , Proteína do Retinoblastoma/metabolismo , Inibidores de Proteínas Quinases/farmacologia , Inibidores de Proteínas Quinases/uso terapêutico
17.
Sci Transl Med ; 15(715): eadf8977, 2023 09 27.
Artigo em Inglês | MEDLINE | ID: mdl-37756377

RESUMO

Chemotherapy-induced cognitive dysfunction (chemobrain) is an important adverse sequela of chemotherapy. Chemobrain has been identified by the National Cancer Institute as a poorly understood problem for which current management or treatment strategies are limited or ineffective. Here, we show that chemotherapy treatment with doxorubicin (DOX) in a breast cancer mouse model induced protein kinase A (PKA) phosphorylation of the neuronal ryanodine receptor/calcium (Ca2+) channel type 2 (RyR2), RyR2 oxidation, RyR2 nitrosylation, RyR2 calstabin2 depletion, and subsequent RyR2 Ca2+ leakiness. Chemotherapy was furthermore associated with abnormalities in brain glucose metabolism and neurocognitive dysfunction in breast cancer mice. RyR2 leakiness and cognitive dysfunction could be ameliorated by treatment with a small molecule Rycal drug (S107). Chemobrain was also found in noncancer mice treated with DOX or methotrexate and 5-fluorouracil and could be prevented by treatment with S107. Genetic ablation of the RyR2 PKA phosphorylation site (RyR2-S2808A) also prevented the development of chemobrain. Chemotherapy increased brain concentrations of the tumor necrosis factor-α and transforming growth factor-ß signaling, suggesting that increased inflammatory signaling might contribute to oxidation-driven biochemical remodeling of RyR2. Proteomics and Gene Ontology analysis indicated that the signaling downstream of chemotherapy-induced leaky RyR2 was linked to the dysregulation of synaptic structure-associated proteins that are involved in neurotransmission. Together, our study points to neuronal Ca2+ dyshomeostasis via leaky RyR2 channels as a potential mechanism contributing to chemobrain, warranting further translational studies.


Assuntos
Antineoplásicos , Comprometimento Cognitivo Relacionado à Quimioterapia , Disfunção Cognitiva , Animais , Camundongos , Canal de Liberação de Cálcio do Receptor de Rianodina , Disfunção Cognitiva/induzido quimicamente , Disfunção Cognitiva/tratamento farmacológico , Encéfalo , Doxorrubicina/efeitos adversos
18.
Cancer Res Commun ; 3(9): 1788-1799, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37691854

RESUMO

The FOXA1 pioneer factor is an essential mediator of steroid receptor function in multiple hormone-dependent cancers, including breast and prostate cancers, enabling nuclear receptors such as estrogen receptor (ER) and androgen receptor (AR) to activate lineage-specific growth programs. FOXA1 is also highly expressed in non-small cell lung cancer (NSCLC), but whether and how it regulates tumor growth in this context is not known. Analyzing data from loss-of-function screens, we identified a subset of NSCLC tumor lines where proliferation is FOXA1 dependent. Using rapid immunoprecipitation and mass spectrometry of endogenous protein, we identified chromatin-localized interactions between FOXA1 and glucocorticoid receptor (GR) in these tumor cells. Knockdown of GR inhibited proliferation of FOXA1-dependent, but not FOXA1-independent NSCLC cells. In these FOXA1-dependent models, FOXA1 and GR cooperate to regulate gene targets involved in EGF signaling and G1-S cell-cycle progression. To investigate the therapeutic potential for targeting this complex, we examined the effects of highly selective inhibitors of the GR ligand-binding pocket and found that GR antagonism with ORIC-101 suppressed FOXA1/GR target expression, activation of EGF signaling, entry into the S-phase, and attendant proliferation in vitro and in vivo. Taken together, our findings point to a subset of NSCLCs harboring a dependence on the FOXA1/GR growth program and provide rationale for its therapeutic targeting. Significance: NSCLC is the leading cause of cancer deaths worldwide. There is a need to identify novel druggable dependencies. We identify a subset of NSCLCs dependent on FOXA1-GR and sensitive to GR antagonism.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Fator 3-alfa Nuclear de Hepatócito , Neoplasias Pulmonares , Receptores de Glucocorticoides , Humanos , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Fator de Crescimento Epidérmico , Neoplasias Pulmonares/tratamento farmacológico , Receptores de Glucocorticoides/genética , Fator 3-alfa Nuclear de Hepatócito/genética
19.
Indian J Dermatol ; 68(3): 313-317, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37529443

RESUMO

Lazarine leprosy is an unusual expression of usually borderline tuberculoid (BT) form characterized by spontaneous ulceration of skin lesions. This is presumably the result of an exaggerated type 1 reaction. It commonly occurs in the BT, borderline lepromatous forms and rarely in the lepromatous forms of leprosy. We report two cases of lazarine leprosy in the BT and BT downgrading to borderline lepromatous spectrum in healthy and immunocompetent males.

20.
Cell Rep Med ; 4(7): 101110, 2023 07 18.
Artigo em Inglês | MEDLINE | ID: mdl-37467717

RESUMO

Multiple myeloma (MM) is an incurable malignancy of plasma cells. To identify targets for MM immunotherapy, we develop an integrated pipeline based on mass spectrometry analysis of seven MM cell lines and RNA sequencing (RNA-seq) from 900+ patients. Starting from 4,000+ candidates, we identify the most highly expressed cell surface proteins. We annotate candidate protein expression in many healthy tissues and validate the expression of promising targets in 30+ patient samples with relapsed/refractory MM, as well as in primary healthy hematopoietic stem cells and T cells by flow cytometry. Six candidates (ILT3, SEMA4A, CCR1, LRRC8D, FCRL3, IL12RB1) and B cell maturation antigen (BCMA) present the most favorable profile in malignant and healthy cells. We develop a bispecific T cell engager targeting ILT3 that shows potent killing effects in vitro and decreased tumor burden and prolonged mice survival in vivo, suggesting therapeutic relevance. Our study uncovers MM-associated antigens that hold great promise for immune-based therapies of MM.


Assuntos
Mieloma Múltiplo , Animais , Camundongos , Mieloma Múltiplo/tratamento farmacológico , Mieloma Múltiplo/patologia , Imunoterapia/métodos , Linfócitos T , Plasmócitos/metabolismo
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