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1.
Mol Cell ; 71(4): 637-648.e5, 2018 08 16.
Article in English | MEDLINE | ID: mdl-30118682

ABSTRACT

Although macrophages are armed with potent antibacterial functions, Mycobacterium tuberculosis (Mtb) replicates inside these innate immune cells. Determinants of macrophage intrinsic bacterial control, and the Mtb strategies to overcome them, are poorly understood. To further study these processes, we used an affinity tag purification mass spectrometry (AP-MS) approach to identify 187 Mtb-human protein-protein interactions (PPIs) involving 34 secreted Mtb proteins. This interaction map revealed two factors involved in Mtb pathogenesis-the secreted Mtb protein, LpqN, and its binding partner, the human ubiquitin ligase CBL. We discovered that an lpqN Mtb mutant is attenuated in macrophages, but growth is restored when CBL is removed. Conversely, Cbl-/- macrophages are resistant to viral infection, indicating that CBL regulates cell-intrinsic polarization between antibacterial and antiviral immunity. Collectively, these findings illustrate the utility of this Mtb-human PPI map for developing a deeper understanding of the intricate interactions between Mtb and its host.


Subject(s)
Bacterial Proteins/genetics , HIV/genetics , Host-Pathogen Interactions , Mycobacterium tuberculosis/genetics , Proto-Oncogene Proteins c-cbl/genetics , Virulence Factors/genetics , Animals , Bacterial Proteins/immunology , Cell Line, Tumor , Chlamydia trachomatis/genetics , Chlamydia trachomatis/immunology , Gene Expression Regulation , HIV/immunology , Herpesvirus 8, Human/genetics , Herpesvirus 8, Human/immunology , Humans , Lymphocytes/microbiology , Lymphocytes/virology , Macrophages/microbiology , Macrophages/virology , Mice , Mycobacterium tuberculosis/immunology , Primary Cell Culture , Protein Binding , Protein Interaction Mapping , Proto-Oncogene Proteins c-cbl/deficiency , Proto-Oncogene Proteins c-cbl/immunology , RAW 264.7 Cells , Signal Transduction , Virulence Factors/immunology
2.
Cell Commun Signal ; 22(1): 128, 2024 02 15.
Article in English | MEDLINE | ID: mdl-38360757

ABSTRACT

In pathologies including cancer, aberrant Transforming Growth Factor-ß (TGF-ß) signaling exerts profound tumor intrinsic and extrinsic consequences. Intense clinical endeavors are underway to target this pathway. Central to the success of these interventions is pinpointing factors that decisively modulate the TGF-ß responses. Betaglycan/type III TGF-ß receptor (TßRIII), is an established co-receptor for the TGF-ß superfamily known to bind directly to TGF-ßs 1-3 and inhibin A/B. Betaglycan can be membrane-bound and also undergo ectodomain cleavage to produce soluble-betaglycan that can sequester its ligands. Its extracellular domain undergoes heparan sulfate and chondroitin sulfate glycosaminoglycan modifications, transforming betaglycan into a proteoglycan. We report the unexpected discovery that the heparan sulfate glycosaminoglycan chains on betaglycan are critical for the ectodomain shedding. In the absence of such glycosaminoglycan chains betaglycan is not shed, a feature indispensable for the ability of betaglycan to suppress TGF-ß signaling and the cells' responses to exogenous TGF-ß ligands. Using unbiased transcriptomics, we identified TIMP3 as a key inhibitor of betaglycan shedding thereby influencing TGF-ß signaling. Our results bear significant clinical relevance as modified betaglycan is present in the ascites of patients with ovarian cancer and can serve as a marker for predicting patient outcomes and TGF-ß signaling responses. These studies are the first to demonstrate a unique reliance on the glycosaminoglycan chains of betaglycan for shedding and influence on TGF-ß signaling responses. Dysregulated shedding of TGF-ß receptors plays a vital role in determining the response and availability of TGF-ßs', which is crucial for prognostic predictions and understanding of TGF-ß signaling dynamics.


Subject(s)
Glycosaminoglycans , Ovarian Neoplasms , Humans , Female , Glycosaminoglycans/metabolism , Transforming Growth Factor beta/metabolism , Proteoglycans/metabolism , Receptors, Transforming Growth Factor beta/metabolism , Heparitin Sulfate/metabolism
3.
Bioinformatics ; 36(10): 3292-3294, 2020 05 01.
Article in English | MEDLINE | ID: mdl-32091578

ABSTRACT

SUMMARY: Organoid model systems recapitulate key features of mammalian tissues and enable high throughput experiments. However, the impact of these experiments may be limited by manual, non-standardized, static or qualitative phenotypic analysis. OrgDyn is an open-source and modular pipeline to quantify organoid shape dynamics using a combination of feature- and model-based approaches on time series of 2D organoid contour images. Our pipeline consists of (i) geometrical and signal processing feature extraction, (ii) dimensionality reduction to differentiate dynamical paths, (iii) time series clustering to identify coherent groups of organoids and (iv) dynamical modeling using point distribution models to explain temporal shape variation. OrgDyn can characterize, cluster and model differences among unique dynamical paths that define diverse final shapes, thus enabling quantitative analysis of the molecular basis of tissue development and disease. AVAILABILITY AND IMPLEMENTATION: https://github.com/zakih/organoidDynamics (BSD 3-Clause License). SUPPLEMENTARY INFORMATION: Supplementary data are available at Bioinformatics online.


Subject(s)
Organoids , Software , Animals , Cluster Analysis
4.
Hum Mol Genet ; 24(15): 4340-52, 2015 Aug 01.
Article in English | MEDLINE | ID: mdl-25954033

ABSTRACT

Cleft lip and/or palate (CL/P) are common structural birth defects in humans. We used exome sequencing to study a patient with bilateral CL/P and identified a single nucleotide deletion in the patient and her similarly affected son­c.546_546delG, predicting p.Gln183Argfs*57 in the Distal-less 4 (DLX4) gene. The sequence variant was absent from databases, predicted to be deleterious and was verified by Sanger sequencing. In mammals, there are three Dlx homeobox clusters with closely located gene pairs (Dlx1/Dlx2, Dlx3/Dlx4, Dlx5/Dlx6). In situ hybridization showed that Dlx4 was expressed in the mesenchyme of the murine palatal shelves at E12.5, prior to palate closure. Wild-type human DLX4, but not mutant DLX4_c.546delG, could activate two murine Dlx conserved regulatory elements, implying that the mutation caused haploinsufficiency. We showed that reduced DLX4 expression after short interfering RNA treatment in a human cell line resulted in significant up-regulation of DLX3, DLX5 and DLX6, with reduced expression of DLX2 and significant up-regulation of BMP4, although the increased BMP4 expression was demonstrated only in HeLa cells. We used antisense morpholino oligonucleotides to target the orthologous Danio rerio gene, dlx4b, and found reduced cranial size and abnormal cartilaginous elements. We sequenced DLX4 in 155 patients with non-syndromic CL/P and CP, but observed no sequence variants. From the published literature, Dlx1/Dlx2 double homozygous null mice and Dlx5 homozygous null mice both have clefts of the secondary palate. This first finding of a DLX4 mutation in a family with CL/P establishes DLX4 as a potential cause of human clefts.


Subject(s)
Brain/abnormalities , Cleft Lip/genetics , Cleft Palate/genetics , Homeodomain Proteins/genetics , Jaw Abnormalities/genetics , Transcription Factors/genetics , Zebrafish Proteins/genetics , Animals , Bone Morphogenetic Protein 4/genetics , Brain/pathology , Cleft Lip/pathology , Cleft Palate/pathology , Exome/genetics , Gene Expression Regulation, Developmental , HeLa Cells , High-Throughput Nucleotide Sequencing , Homeodomain Proteins/biosynthesis , Humans , Jaw Abnormalities/pathology , Mesoderm/metabolism , Mice , Mice, Knockout , Morpholinos , Transcription Factors/biosynthesis , Zebrafish
5.
Hum Mol Genet ; 22(16): 3250-8, 2013 Aug 15.
Article in English | MEDLINE | ID: mdl-23591992

ABSTRACT

The major active retinoid, all-trans retinoic acid, has long been recognized as critical for the development of several organs, including the eye. Mutations in STRA6, the gene encoding the cellular receptor for vitamin A, in patients with Matthew-Wood syndrome and anophthalmia/microphthalmia (A/M), have previously demonstrated the importance of retinol metabolism in human eye disease. We used homozygosity mapping combined with next-generation sequencing to interrogate patients with anophthalmia and microphthalmia for new causative genes. We used whole-exome and whole-genome sequencing to study a family with two affected brothers with bilateral A/M and a simplex case with bilateral anophthalmia and hypoplasia of the optic nerve and optic chiasm. Analysis of novel sequence variants revealed homozygosity for two nonsense mutations in ALDH1A3, c.568A>G, predicting p.Lys190*, in the familial cases, and c.1165A>T, predicting p.Lys389*, in the simplex case. Both mutations predict nonsense-mediated decay and complete loss of function. We performed antisense morpholino (MO) studies in Danio rerio to characterize the developmental effects of loss of Aldh1a3 function. MO-injected larvae showed a significant reduction in eye size, and aberrant axonal projections to the tectum were noted. We conclude that ALDH1A3 loss of function causes anophthalmia and aberrant eye development in humans and in animal model systems.


Subject(s)
Aldehyde Oxidoreductases/genetics , Anophthalmos/genetics , Codon, Nonsense/genetics , Microphthalmos/genetics , Optic Chiasm/abnormalities , Optic Nerve/abnormalities , Aldehyde Oxidoreductases/metabolism , Animals , Anophthalmos/metabolism , Child , Child, Preschool , Exome , Eye/growth & development , Eye/pathology , Female , Genome , Homozygote , Humans , Infant , Larva/genetics , Larva/growth & development , Larva/metabolism , Male , Microphthalmos/metabolism , Sequence Analysis, DNA , Sequence Analysis, RNA , Zebrafish/embryology , Zebrafish/genetics
6.
Inorg Chem ; 54(13): 6582-93, 2015 Jul 06.
Article in English | MEDLINE | ID: mdl-26087119

ABSTRACT

In this Article, we present a series of cyclometalated iridium(III) polypyridine complexes of the formula [Ir(N^C)2(N^N)](PF6) that showed dual emission under ambient conditions. The structures of the cyclometalating and diimine ligands were changed systematically to investigate the effects of the substituents on the dual-emission properties of the complexes. On the basis of the photophysical data, the high-energy (HE) and low-energy (LE) emission features of the complexes were assigned to triplet intraligand ((3)IL) and triplet charge-transfer ((3)CT) excited states, respectively. Time-dependent density functional theory (TD-DFT) calculations supported these assignments and indicated that the dual emission resulted from the interruption of the communication between the higher-lying (3)IL and the lower-lying (3)CT states by a triplet amine-to-ligand charge-transfer ((3)NLCT) state. Also, the avidin-binding properties of the biotin complexes were studied by emission titrations, and the results showed that the dual-emissive complexes can be utilized as ratiometric probes for avidin. Additionally, all the complexes exhibited efficient cellular uptake by live HeLa cells. The MTT and Annexin V assays confirmed that no cell death and early apoptosis occurred during the cell imaging experiments. Interestingly, laser-scanning confocal microscopy revealed that the complexes were selectively localized on the cell membrane, mitochondria, or both, depending on the nature of the substituents of the ligands. The results of this work will contribute to the future development of dual-emissive transition metal complexes as ratiometric probes and organelle-selective bioimaging reagents.


Subject(s)
Fluorescent Dyes/chemistry , Models, Molecular , Organometallic Compounds/chemistry , Quantum Theory , Cell Death , Cyclization , Fluorescent Dyes/chemical synthesis , HeLa Cells , Humans , Iridium/chemistry , Microscopy, Confocal , Organometallic Compounds/pharmacokinetics , Pyridines/chemistry
7.
Chemistry ; 20(31): 9633-42, 2014 Jul 28.
Article in English | MEDLINE | ID: mdl-24986185

ABSTRACT

We report the development of a series of rhenium(I) polypyridine complexes appended with an electron-rich diaminoaromatic moiety as phosphorogenic sensors for nitric oxide (NO). The diamine complexes [Re(N^N)(CO)3 (py-DA)][PF6 ] (py-DA=3-(N-(2-amino-5-methoxyphenyl)aminomethyl)pyridine; N^N=1,10-phenanthroline (phen) (1 a), 3,4,7,8-tetramethyl-1,10-phenanthroline (Me4 -phen) (2 a), 4,7-diphenyl-1,10-phenanthroline (Ph2 -phen) (3 a)) have been synthesized and characterized. In contrast to common rhenium(I) diimines, these diamine complexes were very weakly emissive due to quenching of the triplet metal-to-ligand charge-transfer ((3) MLCT) emission by the diaminoaromatic moiety through photoinduced electron transfer (PET). Upon treatment with NO, the complexes were converted into the triazole derivatives [Re(N^N)(CO)3 (py-triazole)][PF6 ] (py-triazole=3-((6-methoxybenzotriazol-1-yl)methyl)pyridine; N^N=phen (1 b), Me4 -phen (2 b), Ph2 -phen (3 b)), resulting in significant emission enhancement (I/I0 ≈60). The diamine complexes exhibited high reaction selectivity to NO, and their emission intensity was found to be independent on pH. Also, these complexes were effectively internalized by HeLa cells and RAW264.7 macrophages with negligible cytotoxicity. Additionally, the use of complex 3 a as an intracellular phosphorogenic sensor for NO has been demonstrated.


Subject(s)
Diamines/chemistry , Nitric Oxide/analysis , Organometallic Compounds/chemistry , Pyridines/chemistry , Rhenium/chemistry , Animals , Diamines/chemical synthesis , Diamines/pharmacokinetics , Diamines/pharmacology , HeLa Cells , Humans , Macrophages/drug effects , Macrophages/metabolism , Mice , Microscopy, Confocal , Organometallic Compounds/chemical synthesis , Organometallic Compounds/pharmacokinetics , Organometallic Compounds/pharmacology , Phenanthrolines/chemical synthesis , Phenanthrolines/chemistry , Phenanthrolines/pharmacokinetics , Phenanthrolines/pharmacology , Pyridines/chemical synthesis , Pyridines/pharmacokinetics , Pyridines/pharmacology
8.
Rev Med Virol ; 23(2): 85-96, 2013 Mar.
Article in English | MEDLINE | ID: mdl-22782620

ABSTRACT

Positive-stranded RNA viruses, like many other viruses, have evolved to exploit the host cellular machinery to their own advantage. In eukaryotic cells, the ubiquitin-proteasome system (UPS) that serves as the major intracellular pathway for protein degradation and modification plays a crucial role in the regulation of many fundamental cellular functions. A growing amount of evidence has suggested that the UPS can be utilized by positive-sense RNA viruses. The UPS eliminates excess viral proteins that prevent viral replication and modulates the function of viral proteins through post-translational modification mediated by ubiquitin or ubiquitin-like proteins. This review will discuss the current understanding of how positive RNA viruses have evolved various mechanisms to usurp the host UPS to modulate the function and stability of viral proteins. In addition to the pro-viral function, UPS-mediated viral protein degradation may also constitute a host defense process against some positive-stranded RNA viral infections. This issue will also be discussed in the current review.


Subject(s)
Host-Pathogen Interactions , Proteasome Endopeptidase Complex/metabolism , RNA Virus Infections/immunology , RNA Virus Infections/pathology , RNA Viruses/physiology , Ubiquitin/metabolism , Virus Replication , Animals , Humans , Protein Stability , Proteolysis , Viral Proteins/metabolism
9.
J Med Educ Curric Dev ; 11: 23821205241241375, 2024.
Article in English | MEDLINE | ID: mdl-38532857

ABSTRACT

Objectives: This study investigates the effectiveness of a virtual format of an advanced communication skills observed structured clinical examination (OSCE) for senior medical students in comparison to an in-person format. The study also examines the emotional support students experience in the virtual setting. Our analysis was based on quantitative data collected through objective checklists and post-OSCE survey results. Methods: The virtual OSCE was a revision of an earlier in-person formative advanced communication skills OSCE for fourth-year medical students. Student performances were assessed by self and peers using objective checklists-the modified Master Interview Rating Scale (mMIRS) and Communication Behavior Checklist (CBC). The mMIRS measured interview process such as avoiding jargon and demonstrating empathy. The CBC examined interview content which included tasks specific to the content of the case. The OSCE was followed by a faculty-led debrief and quantitative survey. The virtual OSCE was conducted in 2021, and the results of the checklists and survey were compared with those collected from two earlier in-person OSCEs. Results: Eighty-three students participated in the virtual OSCE. There was no difference in mMIRS scores between the virtual and in-person OSCE. Overall CBC scores were lower in the virtual OSCE compared to in-person (p < 0.05). Sixty-seven out of 83 (80.7%) students completed the post-OSCE survey. There were no differences between the virtual and in-person OSCE in terms of educational value, whether the OSCE would change the way participants talk to patients, and preparedness to have serious conversations with patients. All respondents somewhat or strongly agreed with feeling emotionally supported during the virtual OSCE. Conclusion: The virtual format was a suitable alternative to an in-person, formative, advanced communication skills OSCE for medical students. The virtual OSCE was educationally effective and was met with student satisfaction and a sense of emotional support. Future virtual iterations must ensure adequate instruction on interview content.

10.
Can J Public Health ; 115(3): 473-476, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38625496

ABSTRACT

Over the past decade, artificial intelligence (AI) has begun to transform Canadian organizations, driven by the promise of improved efficiency, better decision-making, and enhanced client experience. While AI holds great opportunities, there are also near-term impacts on the determinants of health and population health equity that are already emerging. If adoption is unregulated, there is a substantial risk that health inequities could be exacerbated through intended or unintended biases embedded in AI systems. New economic opportunities could be disproportionately leveraged by already privileged workers and owners of AI systems, reinforcing prevailing power dynamics. AI could also detrimentally affect population well-being by replacing human interactions rather than fostering social connectedness. Furthermore, AI-powered health misinformation could undermine effective public health communication. To respond to these challenges, public health must assess and report on the health equity impacts of AI, inform implementation to reduce health inequities, and facilitate intersectoral partnerships to foster development of policies and regulatory frameworks to mitigate risks. This commentary highlights AI's near-term risks for population health to inform a public health response.


RéSUMé: Au cours de la dernière décennie, l'intelligence artificielle (IA) a commencé à transformer les organismes canadiens en leur promettant une plus grande efficience, de meilleurs processus décisionnels et une expérience client enrichie. Bien qu'elle recèle d'immenses possibilités, l'IA aura des effets à court terme ­ qui se font d'ailleurs déjà sentir ­ sur les déterminants de la santé et sur l'équité en santé des populations. Si son adoption n'est pas réglementée, il se peut très bien que les iniquités en santé continuent d'être exacerbées par les préjugés, intentionnels ou non, ancrés dans les systèmes d'IA. Les nouvelles possibilités économiques pourraient être démesurément exploitées par les travailleurs et les travailleuses déjà privilégiés et par les propriétaires des systèmes d'IA, renforçant ainsi la dynamique de pouvoir existante. L'IA pourrait aussi nuire au bien-être des populations en remplaçant les interactions humaines au lieu de favoriser la connexité sociale. De plus, la mésinformation sur la santé alimentée par l'IA pourrait réduire l'efficacité des messages de santé publique. Pour relever ces défis, la santé publique devra évaluer et communiquer les effets de l'IA sur l'équité en santé, en modérer la mise en œuvre pour réduire les iniquités en santé, et faciliter des partenariats intersectoriels pour éclairer l'élaboration de politiques et de cadres réglementaires d'atténuation des risques. Le présent commentaire fait ressortir les risques à court terme de l'IA pour la santé des populations afin d'éclairer la riposte de la santé publique.


Subject(s)
Artificial Intelligence , Population Health , Public Health , Humans , Canada , Professional Role , Public Health Practice , Health Equity
11.
Cancer Med ; 13(17): e7368, 2024 Sep.
Article in English | MEDLINE | ID: mdl-39248018

ABSTRACT

OBJECTIVE: The TGF-ß superfamily member activin, a dimer of the gene products of INHBA and/or INHBB, has been implicated in immune cell maturation and recruitment, but its immune impact within epithelial ovarian cancer (EOC) is not well characterized. We sought to explore differences in activin (INHBA/ Inhibin-ßA and INHBB/ Inhibin-ßB) between malignant and ovarian tissues at the RNA and protein level and assess the relationship between activin and immune cells in EOC. METHODS: Publicly available RNA sequencing data were accessed from GEO (#GSE143897) with normalization and quantification performed via DESeq2. Immune gene expression profile was further explored within the TCGA-OV cohort derived from The Cancer Genome Atlas (TCGA). Immunohistochemical analysis was performed to evaluate activin A and T-cell markers CD8 and FoxP3 at the protein level. ELISA to activin-A was used to assess levels in the ascites of advanced EOC patients. Kaplan-Meier curves were generated to visualize survival outcomes. RESULTS: Gene expression levels of components of the activin signaling pathway were elevated within EOC when compared to a benign cohort, with differences in activin type I/II receptor gene profiles identified. Additionally, INHBA gene expression was linked to lymphocytic immune markers in EOC samples. Immunohistochemistry analysis revealed a positive correlation of CD8 and FOXP3 staining with activin A at the protein level in both primary and metastatic epithelial ovarian cancer samples. Furthermore, Activin-A (inhibin-ßA) is significantly elevated in EOC patient ascites. CONCLUSION: INHBA expression is elevated within EOC, correlating with worse survival, with activin protein levels correlating with specific immune infiltration. Our findings suggest that activin-A may play a role in suppressing anti-tumor immunity in EOC, highlighting its potential as a therapeutic target.


Subject(s)
Activins , Carcinoma, Ovarian Epithelial , Inhibin-beta Subunits , Ovarian Neoplasms , Humans , Female , Carcinoma, Ovarian Epithelial/pathology , Carcinoma, Ovarian Epithelial/immunology , Carcinoma, Ovarian Epithelial/metabolism , Carcinoma, Ovarian Epithelial/genetics , Carcinoma, Ovarian Epithelial/mortality , Ovarian Neoplasms/pathology , Ovarian Neoplasms/immunology , Ovarian Neoplasms/metabolism , Ovarian Neoplasms/mortality , Ovarian Neoplasms/genetics , Inhibin-beta Subunits/genetics , Inhibin-beta Subunits/metabolism , Activins/metabolism , Activins/genetics , Lymphocytes, Tumor-Infiltrating/immunology , Lymphocytes, Tumor-Infiltrating/metabolism , Middle Aged , Gene Expression Regulation, Neoplastic , Biomarkers, Tumor/metabolism , Biomarkers, Tumor/genetics , Forkhead Transcription Factors/metabolism , Forkhead Transcription Factors/genetics
12.
Cells ; 12(5)2023 03 06.
Article in English | MEDLINE | ID: mdl-36899952

ABSTRACT

The development of long-term symptoms of coronavirus disease 2019 (COVID-19) more than four weeks after primary infection, termed "long COVID" or post-acute sequela of COVID-19 (PASC), can implicate persistent neurological complications in up to one third of patients and present as fatigue, "brain fog", headaches, cognitive impairment, dysautonomia, neuropsychiatric symptoms, anosmia, hypogeusia, and peripheral neuropathy. Pathogenic mechanisms of these symptoms of long COVID remain largely unclear; however, several hypotheses implicate both nervous system and systemic pathogenic mechanisms such as SARS-CoV2 viral persistence and neuroinvasion, abnormal immunological response, autoimmunity, coagulopathies, and endotheliopathy. Outside of the CNS, SARS-CoV-2 can invade the support and stem cells of the olfactory epithelium leading to persistent alterations to olfactory function. SARS-CoV-2 infection may induce abnormalities in innate and adaptive immunity including monocyte expansion, T-cell exhaustion, and prolonged cytokine release, which may cause neuroinflammatory responses and microglia activation, white matter abnormalities, and microvascular changes. Additionally, microvascular clot formation can occlude capillaries and endotheliopathy, due to SARS-CoV-2 protease activity and complement activation, can contribute to hypoxic neuronal injury and blood-brain barrier dysfunction, respectively. Current therapeutics target pathological mechanisms by employing antivirals, decreasing inflammation, and promoting olfactory epithelium regeneration. Thus, from laboratory evidence and clinical trials in the literature, we sought to synthesize the pathophysiological pathways underlying neurological symptoms of long COVID and potential therapeutics.


Subject(s)
COVID-19 , Nervous System Diseases , Humans , COVID-19/complications , SARS-CoV-2 , RNA, Viral , Nervous System Diseases/etiology , Inflammation/complications , Post-Acute COVID-19 Syndrome
13.
bioRxiv ; 2023 Aug 29.
Article in English | MEDLINE | ID: mdl-37693479

ABSTRACT

In pathologies such as cancer, aberrant Transforming Growth Factor-ß (TGF-ß) signaling exerts profound tumor intrinsic and extrinsic consequences. Intense clinical endeavors are underway to target this pivotal pathway. Central to the success of these interventions is pinpointing factors that decisively modulate the TGF-ß responses. Betaglycan/type III TGF-ß receptor (TßRIII), is an established co-receptor for the TGF-ß superfamily known to bind directly to TGF-ßs 1-3 and inhibin A/B. While betaglycan can be membrane-bound, it can also undergo ectodomain cleavage to produce soluble-betaglycan that can sequester its ligands. The extracellular domain of betaglycan undergoes heparan sulfate and chondroitin sulfate glycosaminoglycan modifications, transforming betaglycan into a proteoglycan. Here we report the unexpected discovery that the heparan sulfate modifications are critical for the ectodomain shedding of betaglycan. In the absence of such modifications, betaglycan is not shed. Such shedding is indispensable for the ability of betaglycan to suppress TGF-ß signaling and the cells' responses to exogenous TGF-ß ligands. Using unbiased transcriptomics, we identified TIMP3 as a key regulator of betaglycan shedding and thereby TGF-ß signaling. Our results bear significant clinical relevance as modified betaglycan is present in the ascites of patients with ovarian cancer and can serve as a marker for predicting patient outcomes and TGF-ß signaling responses. These studies are the first to demonstrate a unique reliance on the glycosaminoglycan modifications of betaglycan for shedding and influence on TGF-ß signaling responses. Dysregulated shedding of TGF-ß receptors plays a vital role in determining the response and availability of TGF-ßs', which is crucial for prognostic predictions and understanding of TGF-ß signaling dynamics.

14.
Inorg Chem ; 51(24): 13289-302, 2012 Dec 17.
Article in English | MEDLINE | ID: mdl-23198846

ABSTRACT

We report here a new class of biological reagents derived from luminescent rhenium(I) polypyridine complexes modified with a poly(ethylene glycol) (PEG) pendant. The PEG-amine complexes [Re(N(^)N)(CO)(3)(py-PEG-NH(2))](PF(6)) (py-PEG-NH(2) = 3-amino-5-(N-(2-(ω-methoxypoly(1-oxapropyl))ethyl)aminocarbonyl)pyridine, MW(PEG) = 5000 Da, PDI(PEG) < 1.08; N(^)N = 1,10-phenanthroline (phen) (1-PEG-NH(2)), 3,4,7,8-tetramethyl-1,10-phenanthroline (Me(4)-phen) (2-PEG-NH(2)), 4,7-diphenyl-1,10-phenanthroline (Ph(2)-phen) (3-PEG-NH(2))) and [Re(bpy-PEG)(CO)(3)(py-NH(2))](PF(6)) (bpy-PEG = 4-(N-(2-(ω-methoxypoly(1-oxapropyl))ethyl)aminocarbonyl)-4'-methyl-2,2'-bipyridine; py-NH(2) = 3-aminopyridine) (4-PEG-NH(2)) have been synthesized and characterized. The photophysical properties, lipophilicity, water solubility, cytotoxic activity, and cellular uptake properties of these complexes have been compared to those of their PEG-free counterparts [Re(N(^)N)(CO)(3)(py-Et-NH(2))](PF(6)) (py-Et-NH(2) = 3-amino-5-(N-(ethyl)aminocarbonyl)pyridine; N(^)N = phen (1-Et-NH(2)), Me(4)-phen (2-Et-NH(2)), Ph(2)-phen (3-Et-NH(2))) and [Re(bpy-Et)(CO)(3)(py-NH(2))](PF(6)) (bpy-Et = 4-(N-(ethyl)aminocarbonyl)-4'-methyl-2,2'-bipyridine) (4-Et-NH(2)). The PEG complexes exhibited significantly higher water solubility and lower cytotoxicity (IC(50) = 6.6 to 1152 µM) than their PEG-free counterparts (IC(50) = 3.6 to 159 µM), indicating that the covalent attachment of a PEG pendant to rhenium(I) polypyridine complexes is an effective way to increase their biocompatibility. The amine complexes 1-PEG-NH(2)-4-PEG-NH(2) have been activated with thiophosgene to yield the isothiocyanate complexes [Re(N(^)N)(CO)(3)(py-PEG-NCS)](PF(6)) (py-PEG-NCS = 3-isothiocyanato-5-(N-(2-(ω-methoxypoly(1-oxapropyl))ethyl)aminocarbonyl)pyridine; N(^)N = phen (1-PEG-NCS), Me(4)-phen (2-PEG-NCS), Ph(2)-phen (3-PEG-NCS)), and [Re(bpy-PEG)(CO)(3)(py-NCS)](PF(6)) (py-NCS = 3-isothiocyanatopyridine) (4-PEG-NCS) as a new class of luminescent PEGylation reagents. To examine their PEGylation properties, these isothiocyanate complexes have been reacted with a model substrate n-butylamine, resulting in the formation of the thiourea complexes [Re(N(^)N)(CO)(3)(py-PEG-Bu)](PF(6)) (py-PEG-Bu = 3-n-butylthioureidyl-5-(N-(2-(ω-methoxypoly(1-oxapropyl))ethyl)aminocarbonyl)pyridine; N(^)N = phen (1-PEG-Bu), Me(4)-phen (2-PEG-Bu), Ph(2)-phen (3-PEG-Bu)), and [Re(bpy-PEG)(CO)(3)(py-Bu)](PF(6)) (py-Bu = 3-n-butylthioureidylpyridine) (4-PEG-Bu). Additionally, bovine serum albumin (BSA) and poly(ethyleneimine) (PEI) have been PEGylated with the isothiocyanate complexes to yield bioconjugates 1-PEG-BSA-4-PEG-BSA and 1-PEG-PEI-4-PEG-PEI, respectively. Upon irradiation, all the PEGylated BSA and PEI conjugates exhibited intense and long-lived emission in aqueous buffer under ambient conditions. The DNA-binding and polyplex-formation properties of conjugate 3-PEG-PEI have been studied and compared with those of unmodified PEI. Furthermore, the in vivo toxicity of complex 3-PEG-NH(2) and its PEG-free counterpart 3-Et-NH(2) has been investigated using zebrafish embryos as an animal model. Embryos treated with the PEG complex at high concentrations revealed delayed hatching, which has been ascribed to hypoxia as a result of adhering of the complex to the external surface of the chorion.


Subject(s)
Coordination Complexes/chemical synthesis , Polyethylene Glycols/chemistry , Rhenium/chemistry , Water/chemistry , Animals , Antineoplastic Agents/pharmacokinetics , Antineoplastic Agents/pharmacology , Cisplatin/pharmacology , Coordination Complexes/chemistry , Coordination Complexes/pharmacokinetics , Embryo, Nonmammalian/drug effects , HeLa Cells , Humans , Inhibitory Concentration 50 , Luminescence , Microscopy, Confocal , Models, Animal , Molecular Structure , Photochemistry , Solubility , Zebrafish
15.
Med Clin North Am ; 106(4): 653-662, 2022 Jul.
Article in English | MEDLINE | ID: mdl-35725231

ABSTRACT

Establishing goals of care (GOC) is a crucial component of a patient's treatment plan. The need for better physician-patient communication in this area has been recognized for decades, yet several gaps remain. Challenges exist for both physician and patient. Physicians should pursue a patient-led approach, exercise cultural competency, and use various communication techniques to guide patients when establishing GOC.


Subject(s)
Patient Care Planning , Physicians , Communication , Humans , Palliative Care , Physician-Patient Relations
16.
Commun Biol ; 5(1): 536, 2022 06 02.
Article in English | MEDLINE | ID: mdl-35654828

ABSTRACT

Hypoxia, a driver of tumor growth and metastasis, regulates angiogenic pathways that are targets for vessel normalization and ovarian cancer management. However, toxicities and resistance to anti-angiogenics can limit their use making identification of new targets vital. Inhibin, a heteromeric TGFß ligand, is a contextual regulator of tumor progression acting as an early tumor suppressor, yet also an established biomarker for ovarian cancers. Here, we find that hypoxia increases inhibin levels in ovarian cancer cell lines, xenograft tumors, and patients. Inhibin is regulated primarily through HIF-1, shifting the balance under hypoxia from activins to inhibins. Hypoxia regulated inhibin promotes tumor growth, endothelial cell invasion and permeability. Targeting inhibin in vivo through knockdown and anti-inhibin strategies robustly reduces permeability in vivo and alters the balance of pro and anti-angiogenic mechanisms resulting in vascular normalization. Mechanistically, inhibin regulates permeability by increasing VE-cadherin internalization via ACVRL1 and CD105, a receptor complex that we find to be stabilized directly by inhibin. Our findings demonstrate direct roles for inhibins in vascular normalization via TGF-ß receptors providing new insights into the therapeutic significance of inhibins as a strategy to normalize the tumor vasculature in ovarian cancer.


Subject(s)
Inhibins , Ovarian Neoplasms , Activin Receptors, Type II/metabolism , Activins/metabolism , Capillary Permeability , Female , Humans , Hypoxia , Inhibins/metabolism , Ovarian Neoplasms/pathology
17.
Life Sci Alliance ; 5(11)2022 11.
Article in English | MEDLINE | ID: mdl-35820706

ABSTRACT

Metastatic growth of ovarian cancer cells into the peritoneal cavity requires adaptation to various cellular stress factors to facilitate cell survival and growth. Here, we demonstrate the role of PVT1, one such stress induced long non-coding RNA, in ovarian cancer growth and metastasis. PVT1 is an amplified and overexpressed lncRNA in ovarian cancer with strong predictive value for survival and response to targeted therapeutics. We find that expression of PVT1 is regulated by tumor cells in response to cellular stress, particularly loss of cell-cell contacts and changes in matrix rigidity occurring in a YAP1-dependent manner. Induction of PVT1 promotes tumor cell survival, growth, and migration. Conversely, reducing PVT1 levels robustly abrogates metastatic behavior and tumor cell dissemination in cell lines and syngeneic transplantation models in vivo. We find that reducing PVT1 causes widespread changes in the transcriptome leading to alterations in cellular stress response and metabolic pathways including doxorubicin metabolism, which impacts chemosensitivity. Together, these findings implicate PVT1 as a promising therapeutic target to suppress metastasis and chemoresistance in ovarian cancer.


Subject(s)
Ovarian Neoplasms , RNA, Long Noncoding , Cell Proliferation/physiology , Drug Resistance, Neoplasm , Female , Humans , Ovarian Neoplasms/drug therapy , Ovarian Neoplasms/genetics , Ovarian Neoplasms/metabolism , Ovarian Neoplasms/pathology , RNA, Long Noncoding/genetics , RNA, Long Noncoding/metabolism
18.
Neurocrit Care ; 14(2): 162-7, 2011 Apr.
Article in English | MEDLINE | ID: mdl-21125348

ABSTRACT

BACKGROUND: Silent infarction is common in poor-grade subarachnoid hemorrhage (SAH) patients and associated with poor outcome. Invasive neuromonitoring devices may detect changes in cerebral metabolism and oxygenation. METHODS: From a consecutive series of 32 poor-grade SAH patients we identified all CT-scans obtained during multimodal neuromonitoring and analyzed microdialysis parameters and brain tissue oxygen tension (PbtO2) preceding CT-scanning. RESULTS: Eighteen percent of the reviewed head-CTs (12/67) revealed new infarcts. Of the eight infarcts in the vascular territory of the neuromonitoring, seven were clinically silent. Neuromonitoring changes preceding radiological evidence of infarction included lactate-pyruvate-ratio elevation and brain glucose decreases when compared to those with distant or no ischemia (P ≤ 0.03, respectively). PbtO2 was lower, but this did not reach statistical significance. CONCLUSIONS: These data suggest that there may be distinct changes in brain metabolism and oxygenation associated with the development of silent infarction within the monitored vascular territory in poor-grade SAH patients. Larger prospective studies are needed to determine whether treatment triggered by neuromonitoring data has an impact on outcome.


Subject(s)
Cerebral Infarction/diagnosis , Cerebral Infarction/metabolism , Monitoring, Physiologic/methods , Subarachnoid Hemorrhage/diagnosis , Subarachnoid Hemorrhage/metabolism , Adult , Asymptomatic Diseases , Brain/metabolism , Cerebral Infarction/physiopathology , Critical Care/methods , Female , Glucose/metabolism , Humans , Lactic Acid/metabolism , Male , Microdialysis/methods , Middle Aged , Oxygen/metabolism , Pyruvic Acid/metabolism , Retrospective Studies , Subarachnoid Hemorrhage/physiopathology , Tomography, X-Ray Computed
19.
J Infect Dis ; 202(10): 1553-61, 2010 Nov 15.
Article in English | MEDLINE | ID: mdl-20939732

ABSTRACT

BACKGROUND: The gut is a major reservoir for human immunodeficiency virus (HIV) in patients receiving antiretroviral therapy (ART). We hypothesized that distinct immune environments within the gut may support varying levels of HIV. METHODS: In 8 HIV-1-positive adults who were receiving ART and had CD4(+) T cell counts of >200 cells/µL and plasma viral loads of <40 copies/mL, levels of HIV and T cell activation were measured in blood samples and endoscopic biopsy specimens from the duodenum, ileum, ascending colon, and rectum. RESULTS: HIV DNA and RNA levels per CD4(+) T cell were higher in all 4 gut sites compared with those in the blood. HIV DNA levels increased from the duodenum to the rectum, whereas the median HIV RNA level peaked in the ileum. HIV DNA levels correlated positively with T cell activation markers in peripheral blood mononuclear cells (PBMCs) but negatively with T cell activation markers in the gut. Multiply spliced RNA was infrequently detected in gut, and ratios of unspliced RNA to DNA were lower in the colon and rectum than in PBMCs, which reflects paradoxically low HIV transcription, given the higher level of T cell activation in the gut. CONCLUSIONS: HIV DNA and RNA are both concentrated in the gut, but the inverse relationship between HIV DNA levels and T cell activation in the gut and the paradoxically low levels of HIV expression in the large bowel suggest that different processes drive HIV persistence in the blood and gut. TRIAL REGISTRATION: ClinicalTrials.gov identifier: NCT00884793 (PLUS1).


Subject(s)
Anti-HIV Agents/therapeutic use , HIV Infections/drug therapy , HIV-1/isolation & purification , Intestines/immunology , Intestines/virology , T-Lymphocytes/immunology , Adult , Aged , Antiretroviral Therapy, Highly Active , CD4 Lymphocyte Count , CD4-Positive T-Lymphocytes/immunology , DNA, Viral/analysis , HIV Infections/immunology , HIV Infections/virology , HIV-1/genetics , Humans , Lymphocyte Activation , Male , Middle Aged , RNA, Viral/analysis , RNA, Viral/blood , Viral Load
20.
PLoS One ; 16(4): e0249558, 2021.
Article in English | MEDLINE | ID: mdl-33819300

ABSTRACT

Inhibins and activins are dimeric ligands belonging to the TGFß superfamily with emergent roles in cancer. Inhibins contain an α-subunit (INHA) and a ß-subunit (either INHBA or INHBB), while activins are mainly homodimers of either ßA (INHBA) or ßB (INHBB) subunits. Inhibins are biomarkers in a subset of cancers and utilize the coreceptors betaglycan (TGFBR3) and endoglin (ENG) for physiological or pathological outcomes. Given the array of prior reports on inhibin, activin and the coreceptors in cancer, this study aims to provide a comprehensive analysis, assessing their functional prognostic potential in cancer using a bioinformatics approach. We identify cancer cell lines and cancer types most dependent and impacted, which included p53 mutated breast and ovarian cancers and lung adenocarcinomas. Moreover, INHA itself was dependent on TGFBR3 and ENG/CD105 in multiple cancer types. INHA, INHBA, TGFBR3, and ENG also predicted patients' response to anthracycline and taxane therapy in luminal A breast cancers. We also obtained a gene signature model that could accurately classify 96.7% of the cases based on outcomes. Lastly, we cross-compared gene correlations revealing INHA dependency to TGFBR3 or ENG influencing different pathways themselves. These results suggest that inhibins are particularly important in a subset of cancers depending on the coreceptor TGFBR3 and ENG and are of substantial prognostic value, thereby warranting further investigation.


Subject(s)
Biomarkers, Tumor/metabolism , Computational Biology/methods , Endoglin/metabolism , Gene Regulatory Networks , Inhibins/metabolism , Neoplasms/pathology , Proteoglycans/metabolism , Receptors, Transforming Growth Factor beta/metabolism , Biomarkers, Tumor/genetics , Endoglin/genetics , Humans , Inhibins/genetics , Neoplasms/genetics , Neoplasms/metabolism , Prognosis , Proteoglycans/genetics , Receptors, Transforming Growth Factor beta/genetics , Survival Rate
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