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1.
Cell ; 177(2): 446-462.e16, 2019 04 04.
Article in English | MEDLINE | ID: mdl-30951671

ABSTRACT

Poor reproducibility within and across studies arising from lack of knowledge regarding the performance of extracellular RNA (exRNA) isolation methods has hindered progress in the exRNA field. A systematic comparison of 10 exRNA isolation methods across 5 biofluids revealed marked differences in the complexity and reproducibility of the resulting small RNA-seq profiles. The relative efficiency with which each method accessed different exRNA carrier subclasses was determined by estimating the proportions of extracellular vesicle (EV)-, ribonucleoprotein (RNP)-, and high-density lipoprotein (HDL)-specific miRNA signatures in each profile. An interactive web-based application (miRDaR) was developed to help investigators select the optimal exRNA isolation method for their studies. miRDar provides comparative statistics for all expressed miRNAs or a selected subset of miRNAs in the desired biofluid for each exRNA isolation method and returns a ranked list of exRNA isolation methods prioritized by complexity, expression level, and reproducibility. These results will improve reproducibility and stimulate further progress in exRNA biomarker development.


Subject(s)
Cell-Free Nucleic Acids/isolation & purification , Circulating MicroRNA/isolation & purification , RNA/isolation & purification , Adult , Body Fluids/chemistry , Cell Line , Extracellular Vesicles/metabolism , Female , Healthy Volunteers , Humans , Male , MicroRNAs/isolation & purification , MicroRNAs/metabolism , RNA/metabolism , Reproducibility of Results , Sequence Analysis, RNA/methods
2.
Cell ; 177(2): 463-477.e15, 2019 04 04.
Article in English | MEDLINE | ID: mdl-30951672

ABSTRACT

To develop a map of cell-cell communication mediated by extracellular RNA (exRNA), the NIH Extracellular RNA Communication Consortium created the exRNA Atlas resource (https://exrna-atlas.org). The Atlas version 4P1 hosts 5,309 exRNA-seq and exRNA qPCR profiles from 19 studies and a suite of analysis and visualization tools. To analyze variation between profiles, we apply computational deconvolution. The analysis leads to a model with six exRNA cargo types (CT1, CT2, CT3A, CT3B, CT3C, CT4), each detectable in multiple biofluids (serum, plasma, CSF, saliva, urine). Five of the cargo types associate with known vesicular and non-vesicular (lipoprotein and ribonucleoprotein) exRNA carriers. To validate utility of this model, we re-analyze an exercise response study by deconvolution to identify physiologically relevant response pathways that were not detected previously. To enable wide application of this model, as part of the exRNA Atlas resource, we provide tools for deconvolution and analysis of user-provided case-control studies.


Subject(s)
Cell Communication/physiology , RNA/metabolism , Adult , Body Fluids/chemistry , Cell-Free Nucleic Acids/metabolism , Circulating MicroRNA/metabolism , Extracellular Vesicles/metabolism , Female , Humans , Male , Reproducibility of Results , Sequence Analysis, RNA/methods , Software
3.
Cell ; 160(1-2): 269-84, 2015 Jan 15.
Article in English | MEDLINE | ID: mdl-25594183

ABSTRACT

The stem cells that maintain and repair the postnatal skeleton remain undefined. One model suggests that perisinusoidal mesenchymal stem cells (MSCs) give rise to osteoblasts, chondrocytes, marrow stromal cells, and adipocytes, although the existence of these cells has not been proven through fate-mapping experiments. We demonstrate here that expression of the bone morphogenetic protein (BMP) antagonist gremlin 1 defines a population of osteochondroreticular (OCR) stem cells in the bone marrow. OCR stem cells self-renew and generate osteoblasts, chondrocytes, and reticular marrow stromal cells, but not adipocytes. OCR stem cells are concentrated within the metaphysis of long bones not in the perisinusoidal space and are needed for bone development, bone remodeling, and fracture repair. Grem1 expression also identifies intestinal reticular stem cells (iRSCs) that are cells of origin for the periepithelial intestinal mesenchymal sheath. Grem1 expression identifies distinct connective tissue stem cells in both the bone (OCR stem cells) and the intestine (iRSCs).


Subject(s)
Bone and Bones/cytology , Intercellular Signaling Peptides and Proteins/metabolism , Intestine, Small/cytology , Mesenchymal Stem Cells/cytology , Animals , Cartilage/metabolism , Intestine, Small/metabolism , Mesenchymal Stem Cells/metabolism , Mice , Mice, Inbred C57BL
4.
Genes Dev ; 35(1-2): 59-64, 2021 01 01.
Article in English | MEDLINE | ID: mdl-33303641

ABSTRACT

Here, we showed that the acetylation-defective p53-4KR mice, lacking the ability of cell cycle arrest, senescence, apoptosis, and ferroptosis, were tumor prone but failed to develop early-onset tumors. By identifying a novel p53 acetylation site at lysine K136, we found that simultaneous mutations at all five acetylation sites (p53-5KR) diminished its remaining tumor suppression function. Moreover, the embryonic lethality caused by the deficiency of mdm2 was fully rescued in the background of p535KR/5KR , but not p534KR/4KR background. p53-4KR retained the ability to suppress mTOR function but this activity was abolished in p53-5KR cells. Notably, the early-onset tumor formation observed in p535KR/5KR and p53-null mice was suppressed upon the treatment of the mTOR inhibitor. These results suggest that p53-mediated mTOR regulation plays an important role in both embryonic development and tumor suppression, independent of cell cycle arrest, senescence, apoptosis, and ferroptosis.


Subject(s)
Cell Cycle Checkpoints/genetics , Neoplasms/genetics , TOR Serine-Threonine Kinases/genetics , TOR Serine-Threonine Kinases/metabolism , Tumor Suppressor Protein p53/genetics , Tumor Suppressor Protein p53/metabolism , Acetylation , Animals , Carcinogenesis/drug effects , Carcinogenesis/genetics , Embryo, Mammalian , Lysine/genetics , Lysine/metabolism , Mice , Mutation/genetics , Neoplasms/physiopathology , Proto-Oncogene Proteins c-mdm2/deficiency , Proto-Oncogene Proteins c-mdm2/genetics , Sirolimus/pharmacology , Survival Analysis
5.
Genes Dev ; 35(7-8): 528-541, 2021 04 01.
Article in English | MEDLINE | ID: mdl-33737385

ABSTRACT

Esophageal squamous cell carcinoma (ESCC) is one of the most lethal cancers worldwide and evolves often to lung metastasis. P53R175H (homologous to Trp53R172H in mice) is a common hot spot mutation. How metastasis is regulated by p53R175H in ESCC remains to be investigated. To investigate p53R175H-mediated molecular mechanisms, we used a carcinogen-induced approach in Trp53R172H/- mice to model ESCC. In the primary Trp53R172H/- tumor cell lines, we depleted Trp53R172H (shTrp53) and observed a marked reduction in cell invasion in vitro and lung metastasis burden in a tail-vein injection model in comparing isogenic cells (shCtrl). Furthermore, we performed bulk RNA-seq to compare gene expression profiles of metastatic and primary shCtrl and shTrp53 cells. We identified the YAP-BIRC5 axis as a potential mediator of Trp53R172H -mediated metastasis. We demonstrate that expression of Survivin, an antiapoptotic protein encoded by BIRC5, increases in the presence of Trp53R172H Furthermore, depletion of Survivin specifically decreases Trp53R172H-driven lung metastasis. Mechanistically, Trp53R172H but not wild-type Trp53, binds with YAP in ESCC cells, suggesting their cooperation to induce Survivin expression. Furthermore, Survivin high expression level is associated with increased metastasis in several GI cancers. Taken together, this study unravels new insights into how mutant p53 mediates metastasis.


Subject(s)
Lung Neoplasms/physiopathology , Survivin/genetics , Survivin/metabolism , Animals , Cell Line, Tumor , Disease Models, Animal , Gene Expression Regulation, Neoplastic/genetics , Lung Neoplasms/genetics , Mice , Mutation , Neoplasm Metastasis , Transcriptome , Tumor Suppressor Protein p53/metabolism
6.
Cell ; 155(3): 552-66, 2013 Oct 24.
Article in English | MEDLINE | ID: mdl-24243015

ABSTRACT

Context-specific molecular vulnerabilities that arise during tumor evolution represent an attractive intervention target class. However, the frequency and diversity of somatic lesions detected among lung tumors can confound efforts to identify these targets. To confront this challenge, we have applied parallel screening of chemical and genetic perturbations within a panel of molecularly annotated NSCLC lines to identify intervention opportunities tightly linked to molecular response indicators predictive of target sensitivity. Anchoring this analysis on a matched tumor/normal cell model from a lung adenocarcinoma patient identified three distinct target/response-indicator pairings that are represented with significant frequencies (6%-16%) in the patient population. These include NLRP3 mutation/inflammasome activation-dependent FLIP addiction, co-occurring KRAS and LKB1 mutation-driven COPI addiction, and selective sensitivity to a synthetic indolotriazine that is specified by a seven-gene expression signature. Target efficacies were validated in vivo, and mechanism-of-action studies informed generalizable principles underpinning cancer cell biology.


Subject(s)
Carcinoma, Non-Small-Cell Lung/metabolism , Drug Screening Assays, Antitumor , Indoles/pharmacology , Lung Neoplasms/metabolism , Triazines/pharmacology , Animals , CASP8 and FADD-Like Apoptosis Regulating Protein/metabolism , Carcinoma, Non-Small-Cell Lung/pathology , Carrier Proteins , Cell Line, Tumor , Coatomer Protein/metabolism , Female , Genes, ras , Heterografts , Humans , Lung Neoplasms/pathology , Lysosomes/metabolism , Mice , Molecular Targeted Therapy , NLR Family, Pyrin Domain-Containing 3 Protein , Neoplasm Transplantation , Oxidative Phosphorylation
7.
Nature ; 610(7930): 190-198, 2022 10.
Article in English | MEDLINE | ID: mdl-36131018

ABSTRACT

Although melanoma is notorious for its high degree of heterogeneity and plasticity1,2, the origin and magnitude of cell-state diversity remains poorly understood. Equally, it is unclear whether growth and metastatic dissemination are supported by overlapping or distinct melanoma subpopulations. Here, by combining mouse genetics, single-cell and spatial transcriptomics, lineage tracing and quantitative modelling, we provide evidence of a hierarchical model of tumour growth that mirrors the cellular and molecular logic underlying the cell-fate specification and differentiation of the embryonic neural crest. We show that tumorigenic competence is associated with a spatially localized perivascular niche, a phenotype acquired through an intercellular communication pathway established by endothelial cells. Consistent with a model in which only a fraction of cells are fated to fuel growth, temporal single-cell tracing of a population of melanoma cells with a mesenchymal-like state revealed that these cells do not contribute to primary tumour growth but, instead, constitute a pool of metastatic initiating cells that switch cell identity while disseminating to secondary organs. Our data provide a spatially and temporally resolved map of the diversity and trajectories of melanoma cell states and suggest that the ability to support growth and metastasis are limited to distinct pools of cells. The observation that these phenotypic competencies can be dynamically acquired after exposure to specific niche signals warrant the development of therapeutic strategies that interfere with the cancer cell reprogramming activity of such microenvironmental cues.


Subject(s)
Cell Proliferation , Melanoma , Neoplasm Metastasis , Animals , Cell Communication , Cell Differentiation , Cell Lineage , Cell Tracking , Cellular Reprogramming , Endothelial Cells , Melanoma/genetics , Melanoma/pathology , Mesoderm/pathology , Mice , Neoplasm Metastasis/pathology , Neural Crest/embryology , Phenotype , Single-Cell Analysis , Transcriptome , Tumor Microenvironment
8.
Nat Rev Neurosci ; 23(7): 439-452, 2022 07.
Article in English | MEDLINE | ID: mdl-35505255

ABSTRACT

Recent years have seen a blossoming of theories about the biological and physical basis of consciousness. Good theories guide empirical research, allowing us to interpret data, develop new experimental techniques and expand our capacity to manipulate the phenomenon of interest. Indeed, it is only when couched in terms of a theory that empirical discoveries can ultimately deliver a satisfying understanding of a phenomenon. However, in the case of consciousness, it is unclear how current theories relate to each other, or whether they can be empirically distinguished. To clarify this complicated landscape, we review four prominent theoretical approaches to consciousness: higher-order theories, global workspace theories, re-entry and predictive processing theories and integrated information theory. We describe the key characteristics of each approach by identifying which aspects of consciousness they propose to explain, what their neurobiological commitments are and what empirical data are adduced in their support. We consider how some prominent empirical debates might distinguish among these theories, and we outline three ways in which theories need to be developed to deliver a mature regimen of theory-testing in the neuroscience of consciousness. There are good reasons to think that the iterative development, testing and comparison of theories of consciousness will lead to a deeper understanding of this most profound of mysteries.


Subject(s)
Consciousness , Neurosciences , Humans
9.
Cell ; 148(1-2): 349-61, 2012 Jan 20.
Article in English | MEDLINE | ID: mdl-22265420

ABSTRACT

Metastasis is the leading cause of cancer-associated death but has been difficult to study because it involves a series of rare, stochastic events. To capture these events, we developed a sensitive method to tag and track pancreatic epithelial cells in a mouse model of pancreatic cancer. Tagged cells invaded and entered the bloodstream unexpectedly early, before frank malignancy could be detected by rigorous histologic analysis; this behavior was widely associated with epithelial-to-mesenchymal transition (EMT). Circulating pancreatic cells maintained a mesenchymal phenotype, exhibited stem cell properties, and seeded the liver. EMT and invasiveness were most abundant at inflammatory foci, and induction of pancreatitis increased the number of circulating pancreatic cells. Conversely, treatment with the immunosuppressive agent dexamethasone abolished dissemination. These results provide insight into the earliest events of cellular invasion in situ and suggest that inflammation enhances cancer progression in part by facilitating EMT and entry into the circulation.


Subject(s)
Carcinoma, Pancreatic Ductal/pathology , Epithelial-Mesenchymal Transition , Neoplasm Invasiveness , Pancreatic Neoplasms/pathology , Animals , Carcinoma, Pancreatic Ductal/immunology , Disease Models, Animal , Humans , Mice , Neoplastic Stem Cells/pathology , Pancreatic Neoplasms/immunology , Pancreatitis/pathology
10.
Blood ; 2024 Jun 28.
Article in English | MEDLINE | ID: mdl-38941598

ABSTRACT

T-prolymphocytic leukemia (T-PLL) is a mature T-cell neoplasm associated with marked chemotherapy resistance and continued poor clinical outcomes. Current treatments, i.e. the CD52-antibody alemtuzumab, offer transient responses, with relapses being almost inevitable without consolidating allogeneic transplantation. Recent more detailed concepts of T-PLL's pathobiology fostered the identification of actionable vulnerabilities: (i) altered epigenetics, (ii) defective DNA damage responses, (iii) aberrant cell-cycle regulation, and (iv) deregulated pro-survival pathways, including TCR and JAK/STAT signaling. To further develop related pre-clinical therapeutic concepts, we studied inhibitors of (H)DACs, BCL2, CDK, MDM2, and clas-sical cytostatics, utilizing (a) single-agent and combinatorial compound testing in 20 well-characterized and molecularly-profiled primary T-PLL (validated by additional 42 cases), and (b) 2 independent murine models (syngeneic transplants and patient-derived xenografts). Overall, the most efficient/selective single-agents and combinations (in vitro and in mice) in-cluded Cladribine, Romidepsin ((H)DAC), Venetoclax (BCL2), and/or Idasanutlin (MDM2). Cladribine sensitivity correlated with expression of its target RRM2. T-PLL cells revealed low overall apoptotic priming with heterogeneous dependencies on BCL2 proteins. In additional 38 T-cell leukemia/lymphoma lines, TP53 mutations were associated with resistance towards MDM2 inhibitors. P53 of T-PLL cells, predominantly in wild-type configuration, was amenable to MDM2 inhibition, which increased its MDM2-unbound fraction. This facilitated P53 activa-tion and down-stream signals (including enhanced accessibility of target-gene chromatin re-gions), in particular synergy with insults by Cladribine. Our data emphasize the therapeutic potential of pharmacologic strategies to reinstate P53-mediated apoptotic responses. The identified efficacies and their synergies provide an informative background on compound and patient selection for trial designs in T-PLL.

11.
Circ Res ; 135(5): 575-592, 2024 Aug 16.
Article in English | MEDLINE | ID: mdl-39034919

ABSTRACT

BACKGROUND: The SPAN trial (Stroke Preclinical Assessment Network) is the largest preclinical study testing acute stroke interventions in experimental focal cerebral ischemia using endovascular filament middle cerebral artery occlusion (MCAo). Besides testing interventions against controls, the prospective design captured numerous biological and procedural variables, highlighting the enormous heterogeneity introduced by the multicenter structure that might influence stroke outcomes. Here, we leveraged the unprecedented sample size achieved by the SPAN trial and the prospective design to identify the biological and procedural variables that affect experimental stroke outcomes in transient endovascular filament MCAo. METHODS: The study cohort included all mice enrolled and randomized in the SPAN trial (N=1789). Mice were subjected to 60-minute MCAo and followed for a month. Thirteen biological and procedural independent variables and 4 functional (weight loss and 4-point neuroscore on days 1 and 2, corner test on days 7 and 28, and mortality) and 3 tissue (day 2, magnetic resonance imaging infarct volumes and swelling; day 30, magnetic resonance imaging tissue loss) outcome variables were prospectively captured. Multivariable regression with stepwise elimination was used to identify the predictors and their effect sizes. RESULTS: Older age, active circadian stage at MCAo, and thinner and longer filament silicone tips predicted higher mortality. Older age, larger body weight, longer anesthesia duration, and longer filament tips predicted worse neuroscores, while high-fat diet and blood flow monitoring predicted milder neuroscores. Older age and a high-fat diet predicted worse corner test performance. While shorter filament tips predicted more ipsiversive turning, longer filament tips appeared to predict contraversive turning. Age, sex, and weight interacted when predicting the infarct volume. Older age was associated with smaller infarcts on day 2 magnetic resonance imaging, especially in animals with larger body weights; this association was most conspicuous in females. High-fat diet also predicted smaller infarcts. In contrast, the use of cerebral blood flow monitoring and more severe cerebral blood flow drop during MCAo, longer anesthesia, and longer filament tips all predicted larger infarcts. Bivariate analyses among the dependent variables highlighted a disconnect between tissue and functional outcomes. CONCLUSIONS: Our analyses identified variables affecting endovascular filament MCAo outcome, an experimental stroke model used worldwide. Multiple regression refuted some commonly reported predictors and revealed previously unrecognized associations. Given the multicenter prospective design that represents a sampling of real-world conditions, the degree of heterogeneity mimicking clinical trials, the large number of predictors adjusted for in the multivariable model, and the large sample size, we think this is the most definitive analysis of the predictors of preclinical stroke outcome to date. Future multicenter experimental stroke trials should standardize or at least ensure a balanced representation of the biological and procedural variables identified herein as potential confounders.


Subject(s)
Infarction, Middle Cerebral Artery , Animals , Male , Infarction, Middle Cerebral Artery/diagnostic imaging , Infarction, Middle Cerebral Artery/pathology , Mice , Female , Mice, Inbred C57BL , Disease Models, Animal , Stroke/diagnostic imaging , Magnetic Resonance Imaging , Prospective Studies , Ischemic Stroke/diagnostic imaging
12.
Nature ; 582(7810): 134, 2020 06.
Article in English | MEDLINE | ID: mdl-32483375

ABSTRACT

A Retraction to this paper has been published and can be accessed via a link at the top of the paper.

13.
Mol Cell ; 70(4): 679-694.e7, 2018 05 17.
Article in English | MEDLINE | ID: mdl-29775582

ABSTRACT

Enhancers are thought to activate transcription by physically contacting promoters via looping. However, direct assays demonstrating these contacts are required to mechanistically verify such cellular determinants of enhancer function. Here, we present versatile cell-free assays to further determine the role of enhancer-promoter contacts (EPCs). We demonstrate that EPC is linked to mutually stimulatory transcription at the enhancer and promoter in vitro. SRC-3 was identified as a critical looping determinant for the estradiol-(E2)-regulated GREB1 locus. Surprisingly, the GREB1 enhancer and promoter contact two internal gene body SRC-3 binding sites, GBS1 and GBS2, which stimulate their transcription. Utilizing time-course 3C assays, we uncovered SRC-3-dependent dynamic chromatin interactions involving the enhancer, promoter, GBS1, and GBS2. Collectively, these data suggest that the enhancer and promoter remain "poised" for transcription via their contacts with GBS1 and GBS2. Upon E2 induction, GBS1 and GBS2 disengage from the enhancer, allowing direct EPC for active transcription.


Subject(s)
Breast Neoplasms/genetics , Chromatin/metabolism , Estrogens/pharmacology , Gene Expression Regulation, Neoplastic , Nuclear Receptor Coactivator 3/metabolism , Transcription, Genetic , Binding Sites , Breast Neoplasms/metabolism , Breast Neoplasms/pathology , Chromatin/genetics , Enhancer Elements, Genetic , Estrogen Receptor alpha/genetics , Estrogen Receptor alpha/metabolism , Female , Humans , Nuclear Receptor Coactivator 3/genetics , Promoter Regions, Genetic , Protein Binding , Tumor Cells, Cultured
14.
Proc Natl Acad Sci U S A ; 120(4): e2216436120, 2023 01 24.
Article in English | MEDLINE | ID: mdl-36656865

ABSTRACT

Enhancers not only activate target promoters to stimulate messenger RNA (mRNA) synthesis, but they themselves also undergo transcription to produce enhancer RNAs (eRNAs), the significance of which is not well understood. Transcription at the participating enhancer-promoter pair appears coordinated, but it is unclear why and how. Here, we employ cell-free transcription assays using constructs derived from the human GREB1 locus to demonstrate that transcription at an enhancer and its target promoter is interdependent. This interdependence is observable under conditions where direct enhancer-promoter contact (EPC) takes place. We demonstrate that transcription activation at a participating enhancer-promoter pair is dependent on i) the mutual availability of the enhancer and promoter, ii) the state of transcription at both the enhancer and promoter, iii) local abundance of both eRNA and mRNA, and iv) direct EPC. Our results suggest transcriptional interdependence between the enhancer and the promoter as the basis of their transcriptional concurrence and coordination throughout the genome. We propose a model where transcriptional concurrence, coordination and interdependence are possible if the participating enhancer and promoter are entangled in the form of EPC, reside in a proteinaceous bubble, and utilize shared transcriptional resources and regulatory inputs.


Subject(s)
Enhancer Elements, Genetic , RNA , Humans , Enhancer Elements, Genetic/genetics , Promoter Regions, Genetic/genetics , RNA/genetics , RNA, Messenger/genetics , Transcriptional Activation , Transcription, Genetic , Gene Expression Regulation
15.
Proc Natl Acad Sci U S A ; 120(22): e2302006120, 2023 05 30.
Article in English | MEDLINE | ID: mdl-37216503

ABSTRACT

The stringent response, which leads to persistence of nutrient-starved mycobacteria, is induced by activation of the RelA/SpoT homolog (Rsh) upon entry of a deacylated-tRNA in a translating ribosome. However, the mechanism by which Rsh identifies such ribosomes in vivo remains unclear. Here, we show that conditions inducing ribosome hibernation result in loss of intracellular Rsh in a Clp protease-dependent manner. This loss is also observed in nonstarved cells using mutations in Rsh that block its interaction with the ribosome, indicating that Rsh association with the ribosome is important for Rsh stability. The cryo-EM structure of the Rsh-bound 70S ribosome in a translation initiation complex reveals unknown interactions between the ACT domain of Rsh and components of the ribosomal L7/L12 stalk base, suggesting that the aminoacylation status of A-site tRNA is surveilled during the first cycle of elongation. Altogether, we propose a surveillance model of Rsh activation that originates from its constitutive interaction with the ribosomes entering the translation cycle.


Subject(s)
Mycobacterium , Ribosomes , Ribosomes/genetics , RNA, Transfer/chemistry , Mycobacterium/genetics
16.
Genes Dev ; 32(15-16): 1020-1034, 2018 08 01.
Article in English | MEDLINE | ID: mdl-30068703

ABSTRACT

RNA-binding proteins (RBPs) are expressed broadly during both development and malignant transformation, yet their mechanistic roles in epithelial homeostasis or as drivers of tumor initiation and progression are incompletely understood. Here we describe a novel interplay between RBPs LIN28B and IMP1 in intestinal epithelial cells. Ribosome profiling and RNA sequencing identified IMP1 as a principle node for gene expression regulation downstream from LIN28B In vitro and in vivo data demonstrate that epithelial IMP1 loss increases expression of WNT target genes and enhances LIN28B-mediated intestinal tumorigenesis, which was reversed when we overexpressed IMP1 independently in vivo. Furthermore, IMP1 loss in wild-type or LIN28B-overexpressing mice enhances the regenerative response to irradiation. Together, our data provide new evidence for the opposing effects of the LIN28B-IMP1 axis on post-transcriptional regulation of canonical WNT signaling, with implications in intestinal homeostasis, regeneration and tumorigenesis.


Subject(s)
Carcinogenesis , Gene Expression Regulation , Intestinal Mucosa/metabolism , RNA-Binding Proteins/metabolism , Regulon , Wnt Signaling Pathway , Animals , Cell Line, Tumor , Colorectal Neoplasms/genetics , Colorectal Neoplasms/metabolism , Humans , Intestinal Mucosa/physiology , Mice , Mice, Transgenic , Oncogenes , Protein Biosynthesis , RNA-Binding Proteins/physiology , Regeneration , Stem Cells/metabolism
17.
Hum Mol Genet ; 32(16): 2576-2586, 2023 08 07.
Article in English | MEDLINE | ID: mdl-37184252

ABSTRACT

Prevention of Type 2 diabetes mellitus (T2DM) pandemic needs markers that can precisely predict the disease risk in an individual. Alterations in DNA methylations due to exposure towards environmental risk factors are widely sought markers for T2DM risk prediction. To identify such individual DNA methylation signatures and their effect on disease risk, we performed an epigenome-wide association study (EWAS) in 844 Indian individuals of Indo-European origin. We identified and validated methylation alterations at two novel CpG sites in MIR1287 (cg01178710) and EDN2-SCMH1 (cg04673737) genes associated with T2DM risk at the epigenome-wide-significance-level (P < 1.2 × 10-7). Further, we also replicated the association of two known CpG sites in TXNIP, and CPT1A in the Indian population. With 535 EWAS significant CpGs (P < 1.2 × 10-7) identified in the discovery phase samples, we created a co-methylation network using weighted correlation network analysis and identified four modules among the CpGs. We observed that methylation of one of the module associates with T2DM risk factors (e.g. BMI, insulin and C-peptide) and can be used as markers to segregate T2DM patients with good glycemic control (e.g. low HbA1c) and dyslipidemia (low HDL and high TG) from the other patients. Additionally, an intronic SNP (rs6503650) in the JUP gene, a member of the same module, associated with methylation at all the 14 hub CpG sites of that module as methQTL. Our network-assisted EWAS is the first to systematically explore DNA methylation variations conferring risks to T2DM in Indians and use the identified risk CpG sites for patient segregation with different clinical outcomes. These findings can be useful for better stratification of patients to improve the clinical management and treatment effects.


Subject(s)
Diabetes Mellitus, Type 2 , MicroRNAs , Humans , Epigenome/genetics , Epigenesis, Genetic/genetics , Diabetes Mellitus, Type 2/genetics , Genome-Wide Association Study , CpG Islands/genetics , DNA Methylation/genetics
18.
Nat Chem Biol ; 19(3): 275-283, 2023 03.
Article in English | MEDLINE | ID: mdl-36175661

ABSTRACT

Prevention of infection and propagation of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is a high priority in the Coronavirus Disease 2019 (COVID-19) pandemic. Here we describe S-nitrosylation of multiple proteins involved in SARS-CoV-2 infection, including angiotensin-converting enzyme 2 (ACE2), the receptor for viral entry. This reaction prevents binding of ACE2 to the SARS-CoV-2 spike protein, thereby inhibiting viral entry, infectivity and cytotoxicity. Aminoadamantane compounds also inhibit coronavirus ion channels formed by envelope (E) protein. Accordingly, we developed dual-mechanism aminoadamantane nitrate compounds that inhibit viral entry and, thus, the spread of infection by S-nitrosylating ACE2 via targeted delivery of the drug after E protein channel blockade. These non-toxic compounds are active in vitro and in vivo in the Syrian hamster COVID-19 model and, thus, provide a novel avenue to pursue therapy.


Subject(s)
COVID-19 , Humans , SARS-CoV-2/metabolism , Angiotensin-Converting Enzyme 2/metabolism , Protein Binding , Peptidyl-Dipeptidase A/metabolism
19.
Mol Psychiatry ; 29(4): 929-938, 2024 Apr.
Article in English | MEDLINE | ID: mdl-38177349

ABSTRACT

To bring biomarkers closer to clinical application, they should be generalizable, reliable, and maintain performance within the constraints of routine clinical conditions. The functional striatal abnormalities (FSA), is among the most advanced neuroimaging biomarkers in schizophrenia, trained to discriminate diagnosis, with post-hoc analyses indicating prognostic properties. Here, we attempt to replicate its diagnostic capabilities measured by the area under the curve (AUC) in receiver operator characteristic curves discriminating individuals with psychosis (n = 101) from healthy controls (n = 51) in the Human Connectome Project for Early Psychosis. We also measured the test-retest (run 1 vs 2) and phase encoding direction (i.e., AP vs PA) reliability with intraclass correlation coefficients (ICC). Additionally, we measured effects of scan length on classification accuracy (i.e., AUCs) and reliability (i.e., ICCs). Finally, we tested the prognostic capability of the FSA by the correlation between baseline scores and symptom improvement over 12 weeks of antipsychotic treatment in a separate cohort (n = 97). Similar analyses were conducted for the Yeo networks intrinsic connectivity as a reference. The FSA had good/excellent diagnostic discrimination (AUC = 75.4%, 95% CI = 67.0-83.3%; in non-affective psychosis AUC = 80.5%, 95% CI = 72.1-88.0%, and in affective psychosis AUC = 58.7%, 95% CI = 44.2-72.0%). Test-retest reliability ranged between ICC = 0.48 (95% CI = 0.35-0.59) and ICC = 0.22 (95% CI = 0.06-0.36), which was comparable to that of networks intrinsic connectivity. Phase encoding direction reliability for the FSA was ICC = 0.51 (95% CI = 0.42-0.59), generally lower than for networks intrinsic connectivity. By increasing scan length from 2 to 10 min, diagnostic classification of the FSA increased from AUC = 71.7% (95% CI = 63.1-80.3%) to 75.4% (95% CI = 67.0-83.3%) and phase encoding direction reliability from ICC = 0.29 (95% CI = 0.14-0.43) to ICC = 0.51 (95% CI = 0.42-0.59). FSA scores did not correlate with symptom improvement. These results reassure that the FSA is a generalizable diagnostic - but not prognostic - biomarker. Given the replicable results of the FSA as a diagnostic biomarker trained on case-control datasets, next the development of prognostic biomarkers should be on treatment-response data.


Subject(s)
Biomarkers , Corpus Striatum , Magnetic Resonance Imaging , Neuroimaging , Psychotic Disorders , Schizophrenia , Humans , Male , Female , Psychotic Disorders/physiopathology , Adult , Corpus Striatum/diagnostic imaging , Corpus Striatum/physiopathology , Neuroimaging/methods , Reproducibility of Results , Magnetic Resonance Imaging/methods , Schizophrenia/physiopathology , Schizophrenia/diagnostic imaging , Connectome/methods , Young Adult , Adolescent
20.
Mol Psychiatry ; 29(8): 2399-2407, 2024 Aug.
Article in English | MEDLINE | ID: mdl-38491344

ABSTRACT

Persons diagnosed with schizophrenia (SCZ) or bipolar I disorder (BPI) are at high risk for self-injurious behavior, suicidal ideation, and suicidal behaviors (SB). Characterizing associations between diagnosed health problems, prior pharmacological treatments, and polygenic scores (PGS) has potential to inform risk stratification. We examined self-reported SB and ideation using the Columbia Suicide Severity Rating Scale (C-SSRS) among 3,942 SCZ and 5,414 BPI patients receiving care within the Veterans Health Administration (VHA). These cross-sectional data were integrated with electronic health records (EHRs), and compared across lifetime diagnoses, treatment histories, follow-up screenings, and mortality data. PGS were constructed using available genomic data for related traits. Genome-wide association studies were performed to identify and prioritize specific loci. Only 20% of the veterans who reported SB had a corroborating ICD-9/10 EHR code. Among those without prior SB, more than 20% reported new-onset SB at follow-up. SB were associated with a range of additional clinical diagnoses, and with treatment with specific classes of psychotropic medications (e.g., antidepressants, antipsychotics, etc.). PGS for externalizing behaviors, smoking initiation, suicide attempt, and major depressive disorder were associated with SB. The GWAS for SB yielded no significant loci. Among individuals with a diagnosed mental illness, self-reported SB were strongly associated with clinical variables across several EHR domains. Analyses point to sequelae of substance-related and psychiatric comorbidities as strong correlates of prior and subsequent SB. Nonetheless, past SB was frequently not documented in health records, underscoring the value of regular screening with direct, in-person assessments, especially among high-risk individuals.


Subject(s)
Bipolar Disorder , Genome-Wide Association Study , Schizophrenia , Suicidal Ideation , Veterans , Humans , Bipolar Disorder/genetics , Bipolar Disorder/epidemiology , Schizophrenia/genetics , Schizophrenia/epidemiology , Male , Female , Veterans/psychology , United States/epidemiology , Middle Aged , Adult , Genome-Wide Association Study/methods , Cross-Sectional Studies , Risk Factors , Suicide, Attempted , Self-Injurious Behavior/genetics , Self-Injurious Behavior/epidemiology , Suicide/statistics & numerical data , Suicide/psychology , Genetic Predisposition to Disease/genetics , Aged , Electronic Health Records , Multifactorial Inheritance/genetics
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