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1.
iScience ; 27(9): 110596, 2024 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-39286512

RESUMO

Patients with cancer are at increased risk of death from COVID-19 and have reduced immune responses to SARS-CoV2 vaccines, necessitating regular boosters. We performed comprehensive chart reviews, surveys of patients attitudes, serology for SARS-CoV-2 antibodies and T cell receptor (TCR) ß sequencing for cellular responses on a cohort of 982 cancer patients receiving active cancer therapy accrued between November-3-2020 and Mar-31-2023. We found that 92 · 3% of patients received the primer vaccine, 70 · 8% received one monovalent booster, but only 30 · 1% received a bivalent booster. Booster uptake was lower under age 50, and among African American or Hispanic patients. Nearly all patients seroconverted after 2+ booster vaccinations (>99%) and improved cellular responses, demonstrating that repeated boosters could overcome poor response to vaccination. Receipt of booster vaccinations was associated with a lower risk of all-cause mortality (HR = 0 · 61, p = 0 · 024). Booster uptake in high-risk cancer patients remains low and strategies to encourage booster uptake are needed.

2.
Nat Commun ; 15(1): 5114, 2024 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-38879593

RESUMO

The global scientific response to COVID 19 highlighted the urgent need for increased throughput and capacity in bioanalytical laboratories, especially for the precise quantification of proteins that pertain to health and disease. Acoustic ejection mass spectrometry (AEMS) represents a much-needed paradigm shift for ultra-fast biomarker screening. Here, a quantitative AEMS assays is presented, employing peptide immunocapture to enrich (i) 10 acute phase response (APR) protein markers from plasma, and (ii) SARS-CoV-2 NCAP peptides from nasopharyngeal swabs. The APR proteins were quantified in 267 plasma samples, in triplicate in 4.8 h, with %CV from 4.2% to 10.5%. SARS-CoV-2 peptides were quantified in triplicate from 145 viral swabs in 10 min. This assay represents a 15-fold speed improvement over LC-MS, with instrument stability demonstrated across 10,000 peptide measurements. The combination of speed from AEMS and selectivity from peptide immunocapture enables ultra-high throughput, reproducible quantitative biomarker screening in very large cohorts.


Assuntos
Biomarcadores , COVID-19 , Espectrometria de Massas , SARS-CoV-2 , Humanos , Biomarcadores/sangue , COVID-19/diagnóstico , COVID-19/virologia , COVID-19/sangue , SARS-CoV-2/imunologia , Espectrometria de Massas/métodos , Peptídeos , Proteínas do Nucleocapsídeo de Coronavírus/análise , Fosfoproteínas
3.
J Biol Chem ; 300(6): 107388, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38763333

RESUMO

As part of the classical renin-angiotensin system, the peptidase angiotensin-converting enzyme (ACE) makes angiotensin II which has myriad effects on systemic cardiovascular function, inflammation, and cellular proliferation. Less well known is that macrophages and neutrophils make ACE in response to immune activation which has marked effects on myeloid cell function independent of angiotensin II. Here, we discuss both classical (angiotensin) and nonclassical functions of ACE and highlight mice called ACE 10/10 in which genetic manipulation increases ACE expression by macrophages and makes these mice much more resistant to models of tumors, infection, atherosclerosis, and Alzheimer's disease. In another model called NeuACE mice, neutrophils make increased ACE and these mice are much more resistant to infection. In contrast, ACE inhibitors reduce neutrophil killing of bacteria in mice and humans. Increased expression of ACE induces a marked increase in macrophage oxidative metabolism, particularly mitochondrial oxidation of lipids, secondary to increased peroxisome proliferator-activated receptor α expression, and results in increased myeloid cell ATP. ACE present in sperm has a similar metabolic effect, and the lack of ACE activity in these cells reduces both sperm motility and fertilization capacity. These nonclassical effects of ACE are not due to the actions of angiotensin II but to an unknown molecule, probably a peptide, that triggers a profound change in myeloid cell metabolism and function. Purifying and characterizing this peptide could offer a new treatment for several diseases and prove potentially lucrative.


Assuntos
Células Mieloides , Peptidil Dipeptidase A , Animais , Humanos , Peptidil Dipeptidase A/metabolismo , Peptidil Dipeptidase A/genética , Células Mieloides/metabolismo , Células Mieloides/imunologia , Células Mieloides/efeitos dos fármacos , Macrófagos/metabolismo , Macrófagos/imunologia , Macrófagos/efeitos dos fármacos , Camundongos , Neutrófilos/imunologia , Neutrófilos/metabolismo , Neutrófilos/efeitos dos fármacos , Sistema Renina-Angiotensina/efeitos dos fármacos , Angiotensina II/farmacologia
4.
Nat Cancer ; 5(2): 299-314, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38253803

RESUMO

Contemporary analyses focused on a limited number of clinical and molecular biomarkers have been unable to accurately predict clinical outcomes in pancreatic ductal adenocarcinoma. Here we describe a precision medicine platform known as the Molecular Twin consisting of advanced machine-learning models and use it to analyze a dataset of 6,363 clinical and multi-omic molecular features from patients with resected pancreatic ductal adenocarcinoma to accurately predict disease survival (DS). We show that a full multi-omic model predicts DS with the highest accuracy and that plasma protein is the top single-omic predictor of DS. A parsimonious model learning only 589 multi-omic features demonstrated similar predictive performance as the full multi-omic model. Our platform enables discovery of parsimonious biomarker panels and performance assessment of outcome prediction models learning from resource-intensive panels. This approach has considerable potential to impact clinical care and democratize precision cancer medicine worldwide.


Assuntos
Adenocarcinoma , Carcinoma Ductal Pancreático , Neoplasias Pancreáticas , Humanos , Adenocarcinoma/genética , Adenocarcinoma/cirurgia , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/cirurgia , Multiômica , Inteligência Artificial , Carcinoma Ductal Pancreático/genética , Carcinoma Ductal Pancreático/cirurgia , Inteligência
5.
J Biol Chem ; 300(1): 105486, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37992807

RESUMO

Testis angiotensin-converting enzyme (tACE) plays a critical role in male fertility, but the mechanism is unknown. By using ACE C-domain KO (CKO) mice which lack tACE activity, we found that ATP in CKO sperm was 9.4-fold lower than WT sperm. Similarly, an ACE inhibitor (ACEi) reduced ATP production in mouse sperm by 72%. Metabolic profiling showed that tACE inactivation severely affects oxidative metabolism with decreases in several Krebs cycle intermediates including citric acid, cis-aconitic acid, NAD, α-ketoglutaric acid, succinate, and L-malic acid. We found that sperms lacking tACE activity displayed lower levels of oxidative enzymes (CISY, ODO1, MDHM, QCR2, SDHA, FUMH, CPT2, and ATPA) leading to a decreased mitochondrial respiration rate. The reduced energy production in CKO sperms leads to defects in their physiological functions including motility, acrosine activity, and fertilization in vitro and in vivo. Male mice treated with ACEi show severe impairment in reproductive capacity when mated with female mice. In contrast, an angiotensin II receptor blocker (ARB) had no effect. CKO sperms express significantly less peroxisome proliferators-activated receptor gamma (PPARγ) transcription factor, and its blockade eliminates the functional differences between CKO and WT sperms, indicating PPARγ might mediate the effects of tACE on sperm metabolism. Finally, in a cohort of human volunteers, in vitro treatment with the ramipril or a PPARγ inhibitor reduced ATP production in human sperm and hence its motility and acrosine activity. These findings may have clinical significance since millions of people take ACEi daily, including men who are reproductively active.


Assuntos
Fertilização , PPAR gama , Peptidil Dipeptidase A , Espermatozoides , Animais , Feminino , Humanos , Masculino , Camundongos , Trifosfato de Adenosina/metabolismo , Inibidores da Enzima Conversora de Angiotensina/farmacologia , Fertilização/genética , PPAR gama/genética , PPAR gama/metabolismo , Espermatozoides/efeitos dos fármacos , Espermatozoides/metabolismo , Testículo/enzimologia , Camundongos Endogâmicos C57BL , Peptidil Dipeptidase A/genética , Peptidil Dipeptidase A/metabolismo , Proteínas Mitocondriais/genética , Técnicas de Inativação de Genes , Fosforilação Oxidativa
6.
medRxiv ; 2023 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-37961284

RESUMO

Patients with cancer are at increased risk of death from COVID-19 and have reduced immune responses to SARS-CoV2 vaccines, necessitating regular boosters. We performed comprehensive chart reviews, surveys of patients attitudes, serology for SARS-CoV-2 antibodies and T-cell receptor (TCR) ß sequencing for cellular responses on a cohort of 982 cancer patients receiving active cancer therapy accrued between November-3-2020 and Mar-31-2023. We found that 92·3% of patients received the primer vaccine, 70·8% received one monovalent booster, but only 30·1% received a bivalent booster. Booster uptake was lower under age 50, and among African American or Hispanic patients. Nearly all patients seroconverted after 2+ booster vaccinations (>99%) and improved cellular responses, demonstrating that repeated boosters could overcome poor response to vaccination. Receipt of booster vaccinations was associated with a lower risk of all-cause mortality (HR=0·61, P=0·024). Booster uptake in high-risk cancer patients remains low and strategies to encourage booster uptake are needed. Highlights: COVID-19 booster vaccinations increase antibody levels and maintain T-cell responses against SARS-CoV-2 in patients receiving various anti-cancer therapiesBooster vaccinations reduced all-cause mortality in patientsA significant proportion of patients remain unboosted and strategies are needed to encourage patients to be up-to-date with vaccinations.

7.
Cancers (Basel) ; 14(21)2022 Oct 27.
Artigo em Inglês | MEDLINE | ID: mdl-36358691

RESUMO

Head and neck squamous cell carcinoma (HNSCC) is a highly aggressive disease with poor prognosis, which is mainly due to drug resistance. The biology determining the response to chemo-radiotherapy in HNSCC is poorly understood. Using clinical samples, we found that miR124-3p and miR766-3p are overexpressed in chemo-radiotherapy-resistant (non-responder) HNSCC, as compared to responder tumors. Our study shows that inhibition of miR124-3p and miR766-3p enhances the sensitivity of HNSCC cell lines, CAL27 and FaDu, to 5-fluorouracil and cisplatin (FP) chemotherapy and radiotherapy. In contrast, overexpression of miR766-3p and miR124-3p confers a resistance phenotype in HNSCC cells. The upregulation of miR124-3p and miR766-3p is associated with increased HNSCC cell invasion and migration. In a xenograft mouse model, inhibition of miR124-3p and miR766-3p enhanced the efficacy of chemo-radiotherapy with reduced growth of resistant HNSCC. For the first time, we identified that miR124-3p and miR766-3p attenuate expression of CREBRF and NR3C2, respectively, in HNSCC, which promotes aggressive tumor behavior by inducing the signaling axes CREB3/ATG5 and ß-catenin/c-Myc. Since miR124-3p and miR766-3p affect complementary pathways, combined inhibition of these two miRNAs shows an additive effect on sensitizing cancer cells to chemo-radiotherapy. In conclusion, our study demonstrated a novel miR124-3p- and miR766-3p-based biological mechanism governing treatment-resistant HNSCC, which can be targeted to improve clinical outcomes in HNSCC.

8.
Nat Med ; 28(9): 1813-1822, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-36064599

RESUMO

Amyotrophic lateral sclerosis (ALS) involves progressive motor neuron loss, leading to paralysis and death typically within 3-5 years of diagnosis. Dysfunctional astrocytes may contribute to disease and glial cell line-derived neurotrophic factor (GDNF) can be protective. Here we show that human neural progenitor cells transduced with GDNF (CNS10-NPC-GDNF) differentiated to astrocytes protected spinal motor neurons and were safe in animal models. CNS10-NPC-GDNF were transplanted unilaterally into the lumbar spinal cord of 18 ALS participants in a phase 1/2a study (NCT02943850). The primary endpoint of safety at 1 year was met, with no negative effect of the transplant on motor function in the treated leg compared with the untreated leg. Tissue analysis of 13 participants who died of disease progression showed graft survival and GDNF production. Benign neuromas near delivery sites were common incidental findings at post-mortem. This study shows that one administration of engineered neural progenitors can provide new support cells and GDNF delivery to the ALS patient spinal cord for up to 42 months post-transplantation.


Assuntos
Esclerose Lateral Amiotrófica , Células-Tronco Neurais , Esclerose Lateral Amiotrófica/terapia , Animais , Modelos Animais de Doenças , Fator Neurotrófico Derivado de Linhagem de Célula Glial/genética , Humanos , Medula Espinal , Superóxido Dismutase
9.
Am J Respir Cell Mol Biol ; 67(6): 623-631, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36036918

RESUMO

The epithelium lining airspaces of the human lung is maintained by regional stem cells, including basal cells of pseudostratified airways and alveolar type 2 (AT2) pneumocytes of the gas-exchange region. Despite effective techniques for long-term preservation of airway basal cells, procedures for efficient preservation of functional epithelial cell types of the distal gas-exchange region are lacking. Here we detail a method for cryobanking of epithelial cells from either mouse or human lung tissue for preservation of their phenotypic and functional characteristics. Flow cytometric profiling, epithelial organoid-forming efficiency, and single-cell transcriptomic analysis were used to compare cells recovered from cryobanked tissue with those of freshly dissociated tissue. AT2 cells within single-cell suspensions of enzymatically digested cryobanked distal lung tissue retained expression of the pan-epithelial marker CD326 and the AT2 cell surface antigen recognized by monoclonal antibody HT II-280, allowing antibody-mediated enrichment and downstream analysis. Isolated AT2 cells from cryobanked tissue were comparable with those of freshly dissociated tissue both in their single-cell transcriptome and their capacity for in vitro organoid formation in three-dimensional cultures. We conclude that the cryobanking method described herein allows long-term preservation of distal human lung tissue for downstream analysis of lung cell function and molecular phenotype and is ideally suited for the creation of an easily accessible tissue resource for the research community.


Assuntos
Células Epiteliais , Pulmão , Humanos , Camundongos , Animais , Diferenciação Celular/fisiologia , Células Epiteliais/metabolismo , Células Epiteliais Alveolares/metabolismo , Fenótipo
10.
Cancer Res ; 81(24): 6273-6280, 2021 12 15.
Artigo em Inglês | MEDLINE | ID: mdl-34759001

RESUMO

Longitudinal studies of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) vaccine-induced immune responses in patients with cancer are needed to optimize clinical care. In a prospective cohort study of 366 (291 vaccinated) patients, we measured antibody levels [anti-spike (IgG-(S-RBD) and anti-nucleocapsid immunoglobulin] at three time points. Antibody level trajectories and frequency of breakthrough infections were evaluated by tumor type and timing of treatment relative to vaccination. IgG-(S-RBD) at peak response (median = 42 days after dose 2) was higher (P = 0.002) and remained higher after 4 to 6 months (P = 0.003) in patients receiving mRNA-1273 compared with BNT162b2. Patients with solid tumors attained higher peak levels (P = 0.001) and sustained levels after 4 to 6 months (P < 0.001) compared with those with hematologic malignancies. B-cell targeted treatment reduced peak (P = 0.001) and sustained antibody responses (P = 0.003). Solid tumor patients receiving immune checkpoint inhibitors before vaccination had lower sustained antibody levels than those who received treatment after vaccination (P = 0.043). Two (0.69%) vaccinated and one (1.9%) unvaccinated patient had severe COVID-19 illness during follow-up. Our study shows variation in sustained antibody responses across cancer populations receiving various therapeutic modalities, with important implications for vaccine booster timing and patient selection. SIGNIFICANCE: Long-term studies of immunogenicity of SARS-CoV-2 vaccines in patients with cancer are needed to inform evidence-based guidelines for booster vaccinations and to tailor sequence and timing of vaccinations to elicit improved humoral responses.


Assuntos
Vacina de mRNA-1273 contra 2019-nCoV , Vacina BNT162 , COVID-19/imunologia , COVID-19/prevenção & controle , Imunidade Humoral , Neoplasias/imunologia , SARS-CoV-2 , Vacinação/normas , Adulto , Idoso , Anticorpos Antivirais , COVID-19/epidemiologia , Feminino , Humanos , Programas de Imunização , Imunoglobulina G , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Neoplasias/complicações , Neoplasias/patologia , Estudos Prospectivos , Inquéritos e Questionários , Fatores de Tempo , Vacinação/métodos
11.
Andrologia ; 53(11): e14186, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34514615

RESUMO

It has been proposed that men hospitalised with COVID-19 be treated with oestrogen or progesterone to improve COVID-19 outcomes. Transgender women (male-to-female) are routinely treated with oestrogen or oestrogen +progesterone for feminisation which provides a model for the effect of feminising hormones on testicular tissue. Our goal was to analyse differences in ACE-2 expression in testicles of trans-women taking oestrogen or oestrogen +progesterone. Orchiectomy specimens were collected from trans-women undergoing gender-affirming surgery, who were taking oestrogen or oestrogen+progesterone preoperatively. For controls, we used benign orchiectomy specimens from cis-gender men. All specimens were stained with H&E, Trichrome (fibrosis), insulin-like 3 antibody (Leydig cell) and ACE-2 IHC. Cells per high-powered field were counted by cell type (Leydig, Sertoli and Germ). Stain intensity was rated on a 0-2 scale. On immunohistochemistry staining for Leydig cells and ACE-2 staining, the oestrogen+progesterone cohort had fewer Leydig cells compared with controls. The oestrogen+progesterone cohort also had greater degree of tissue fibrosis compared with controls and the oestrogen cohort. This work supports the hopeful possibility that a short course of progesterone (or oestrogen+progesterone) could downregulate ACE-2 to protect men from COVID-19 infection.


Assuntos
Enzima de Conversão de Angiotensina 2 , Estrogênios , Enzima de Conversão de Angiotensina 2/efeitos dos fármacos , Enzima de Conversão de Angiotensina 2/genética , COVID-19 , Estrogênios/farmacologia , Feminino , Humanos , Células Intersticiais do Testículo , Masculino , SARS-CoV-2 , Testículo
12.
Nat Commun ; 12(1): 4906, 2021 08 12.
Artigo em Inglês | MEDLINE | ID: mdl-34385456

RESUMO

Neoadjuvant chemotherapy (NAC) prior to surgery and immune checkpoint therapy (ICT) have revolutionized bladder cancer management. However, stratification of patients that would benefit most from these modalities remains a major clinical challenge. Here, we combine single nuclei RNA sequencing with spatial transcriptomics and single-cell resolution spatial proteomic analysis of human bladder cancer to identify an epithelial subpopulation with therapeutic response prediction ability. These cells express Cadherin 12 (CDH12, N-Cadherin 2), catenins, and other epithelial markers. CDH12-enriched tumors define patients with poor outcome following surgery with or without NAC. In contrast, CDH12-enriched tumors exhibit superior response to ICT. In all settings, patient stratification by tumor CDH12 enrichment offers better prediction of outcome than currently established bladder cancer subtypes. Molecularly, the CDH12 population resembles an undifferentiated state with inherently aggressive biology including chemoresistance, likely mediated through progenitor-like gene expression and fibroblast activation. CDH12-enriched cells express PD-L1 and PD-L2 and co-localize with exhausted T-cells, possibly mediated through CD49a (ITGA1), providing one explanation for ICT efficacy in these tumors. Altogether, this study describes a cancer cell population with an intriguing diametric response to major bladder cancer therapeutics. Importantly, it also provides a compelling framework for designing biomarker-guided clinical trials.


Assuntos
Caderinas/genética , Células Epiteliais/metabolismo , Regulação Neoplásica da Expressão Gênica , Imunoterapia/métodos , Neoplasias da Bexiga Urinária/terapia , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , Proteínas Relacionadas a Caderinas , Caderinas/metabolismo , Cateninas/genética , Cateninas/metabolismo , Perfilação da Expressão Gênica/métodos , Humanos , Estimativa de Kaplan-Meier , Terapia Neoadjuvante/métodos , Avaliação de Resultados em Cuidados de Saúde , Proteômica/métodos , RNA-Seq/métodos , Linfócitos T/metabolismo , Bexiga Urinária/efeitos dos fármacos , Bexiga Urinária/metabolismo , Bexiga Urinária/cirurgia , Neoplasias da Bexiga Urinária/tratamento farmacológico , Neoplasias da Bexiga Urinária/cirurgia
13.
JACC Case Rep ; 3(6): 922-927, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34317656

RESUMO

Clinically significant myocardial infiltration by leukemic cells is a rare phenomenon. We describe a case of a 47-year-old woman with newly diagnosed acute myeloid leukemia and pleuritic chest pain with rapid cardiopulmonary decompensation. Post-mortem analyses showed fibrinous pericarditis and extensive leukemic infiltration of the myocardium. (Level of Difficulty: Intermediate.).

14.
Immunity ; 54(7): 1463-1477.e11, 2021 07 13.
Artigo em Inglês | MEDLINE | ID: mdl-34115964

RESUMO

Acute respiratory distress syndrome (ARDS), an inflammatory condition with high mortality rates, is common in severe COVID-19, whose risk is reduced by metformin rather than other anti-diabetic medications. Detecting of inflammasome assembly in post-mortem COVID-19 lungs, we asked whether and how metformin inhibits inflammasome activation while exerting its anti-inflammatory effect. We show that metformin inhibited NLRP3 inflammasome activation and interleukin (IL)-1ß production in cultured and alveolar macrophages along with inflammasome-independent IL-6 secretion, thus attenuating lipopolysaccharide (LPS)- and SARS-CoV-2-induced ARDS. By targeting electron transport chain complex 1 and independently of AMP-activated protein kinase (AMPK) or NF-κB, metformin blocked LPS-induced and ATP-dependent mitochondrial (mt) DNA synthesis and generation of oxidized mtDNA, an NLRP3 ligand. Myeloid-specific ablation of LPS-induced cytidine monophosphate kinase 2 (CMPK2), which is rate limiting for mtDNA synthesis, reduced ARDS severity without a direct effect on IL-6. Thus, inhibition of ATP and mtDNA synthesis is sufficient for ARDS amelioration.


Assuntos
Trifosfato de Adenosina/metabolismo , DNA Mitocondrial/biossíntese , Inflamassomos/efeitos dos fármacos , Metformina/farmacologia , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Pneumonia/prevenção & controle , Animais , COVID-19/metabolismo , COVID-19/prevenção & controle , Citocinas/genética , Citocinas/metabolismo , DNA Mitocondrial/metabolismo , Humanos , Inflamassomos/metabolismo , Interleucina-1beta/genética , Interleucina-1beta/metabolismo , Lipopolissacarídeos/toxicidade , Metformina/uso terapêutico , Camundongos , Núcleosídeo-Fosfato Quinase/metabolismo , Pneumonia/metabolismo , Síndrome do Desconforto Respiratório/induzido quimicamente , Síndrome do Desconforto Respiratório/prevenção & controle , SARS-CoV-2/patogenicidade
16.
Sci Signal ; 13(628)2020 04 21.
Artigo em Inglês | MEDLINE | ID: mdl-32317369

RESUMO

The tricarboxylic acid (TCA) cycle converts the end products of glycolysis and fatty acid ß-oxidation into the reducing equivalents NADH and FADH2 Although mitochondrial matrix uptake of Ca2+ enhances ATP production, it remains unclear whether deprivation of mitochondrial TCA substrates alters mitochondrial Ca2+ flux. We investigated the effect of TCA cycle substrates on MCU-mediated mitochondrial matrix uptake of Ca2+, mitochondrial bioenergetics, and autophagic flux. Inhibition of glycolysis, mitochondrial pyruvate transport, or mitochondrial fatty acid transport triggered expression of the MCU gatekeeper MICU1 but not the MCU core subunit. Knockdown of mitochondrial pyruvate carrier (MPC) isoforms or expression of the dominant negative mutant MPC1R97W resulted in increased MICU1 protein abundance and inhibition of MCU-mediated mitochondrial matrix uptake of Ca2+ We also found that genetic ablation of MPC1 in hepatocytes and mouse embryonic fibroblasts resulted in reduced resting matrix Ca2+, likely because of increased MICU1 expression, but resulted in changes in mitochondrial morphology. TCA cycle substrate-dependent MICU1 expression was mediated by the transcription factor early growth response 1 (EGR1). Blocking mitochondrial pyruvate or fatty acid flux was linked to increased autophagy marker abundance. These studies reveal a mechanism that controls the MCU-mediated Ca2+ flux machinery and that depends on TCA cycle substrate availability. This mechanism generates a metabolic homeostatic circuit that protects cells from bioenergetic crisis and mitochondrial Ca2+ overload during periods of nutrient stress.


Assuntos
Canais de Cálcio/metabolismo , Proteínas de Ligação ao Cálcio/metabolismo , Proteínas de Transporte de Cátions/metabolismo , Ácidos Graxos/metabolismo , Mitocôndrias Hepáticas/metabolismo , Proteínas de Transporte da Membrana Mitocondrial/metabolismo , Proteínas Mitocondriais/metabolismo , Ácido Pirúvico/metabolismo , Animais , Transporte Biológico Ativo/genética , Canais de Cálcio/genética , Proteínas de Ligação ao Cálcio/genética , Proteínas de Transporte de Cátions/genética , Células HEK293 , Células HeLa , Células Hep G2 , Humanos , Camundongos Knockout , Mitocôndrias Hepáticas/genética , Proteínas de Transporte da Membrana Mitocondrial/genética , Proteínas Mitocondriais/genética
17.
J Clin Invest ; 130(5): 2478-2487, 2020 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-32281946

RESUMO

Familial dysautonomia (FD) is the most prevalent form of hereditary sensory and autonomic neuropathy (HSAN). In FD, a germline mutation in the Elp1 gene leads to Elp1 protein decrease that causes sympathetic neuron death and sympathetic nervous system dysfunction (dysautonomia). Elp1 is best known as a scaffolding protein within the nuclear hetero-hexameric transcriptional Elongator protein complex, but how it functions in sympathetic neuron survival is very poorly understood. Here, we identified a cytoplasmic function for Elp1 in sympathetic neurons that was essential for retrograde nerve growth factor (NGF) signaling and neuron target tissue innervation and survival. Elp1 was found to bind to internalized TrkA receptors in an NGF-dependent manner, where it was essential for maintaining TrkA receptor phosphorylation (activation) by regulating PTPN6 (Shp1) phosphatase activity within the signaling complex. In the absence of Elp1, Shp1 was hyperactivated, leading to premature TrkA receptor dephosphorylation, which resulted in retrograde signaling failure and neuron death. Inhibiting Shp1 phosphatase activity in the absence of Elp1 rescued NGF-dependent retrograde signaling, and in an animal model of FD it rescued abnormal sympathetic target tissue innervation. These results suggest that regulation of retrograde NGF signaling in sympathetic neurons by Elp1 may explain sympathetic neuron loss and physiologic dysautonomia in patients with FD.


Assuntos
Disautonomia Familiar/metabolismo , Fator de Crescimento Neural/metabolismo , Neurônios/metabolismo , Transdução de Sinais , Sistema Nervoso Simpático/metabolismo , Animais , Disautonomia Familiar/genética , Disautonomia Familiar/patologia , Mutação em Linhagem Germinativa , Humanos , Peptídeos e Proteínas de Sinalização Intracelular/genética , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Camundongos , Camundongos Transgênicos , Fator de Crescimento Neural/genética , Neurônios/patologia , Proteína Tirosina Fosfatase não Receptora Tipo 6/genética , Proteína Tirosina Fosfatase não Receptora Tipo 6/metabolismo , Receptor trkA/genética , Receptor trkA/metabolismo , Sistema Nervoso Simpático/patologia
18.
EMBO Rep ; 21(5): e48904, 2020 05 06.
Artigo em Inglês | MEDLINE | ID: mdl-32212315

RESUMO

While the zinc finger transcription factors EGR1, EGR2, and EGR3 are recognized as critical for T-cell function, the role of EGR4 remains unstudied. Here, we show that EGR4 is rapidly upregulated upon TCR engagement, serving as a critical "brake" on T-cell activation. Hence, TCR engagement of EGR4-/- T cells leads to enhanced Ca2+ responses, driving sustained NFAT activation and hyperproliferation. This causes profound increases in IFNγ production under resting and diverse polarizing conditions that could be reversed by pharmacological attenuation of Ca2+ entry. Finally, an in vivo melanoma lung colonization assay reveals enhanced anti-tumor immunity in EGR4-/- mice, attributable to Th1 bias, Treg loss, and increased CTL generation in the tumor microenvironment. Overall, these observations reveal for the first time that EGR4 is a key regulator of T-cell differentiation and function.


Assuntos
Sinalização do Cálcio , Fatores de Transcrição de Resposta de Crescimento Precoce , Neoplasias , Animais , Diferenciação Celular , Ativação Linfocitária , Camundongos , Microambiente Tumoral , Dedos de Zinco
20.
Nat Commun ; 10(1): 3850, 2019 08 28.
Artigo em Inglês | MEDLINE | ID: mdl-31462642

RESUMO

Brain glioma treatment with checkpoint inhibitor antibodies to cytotoxic T-lymphocyte-associated antigen 4 (a-CTLA-4) and programmed cell death-1 (a-PD-1) was largely unsuccessful due to their inability to cross blood-brain barrier (BBB). Here we describe targeted nanoscale immunoconjugates (NICs) on natural biopolymer scaffold, poly(ß-L-malic acid), with covalently attached a-CTLA-4 or a-PD-1 for systemic delivery across the BBB and activation of local brain anti-tumor immune response. NIC treatment of mice bearing intracranial GL261 glioblastoma (GBM) results in an increase of CD8+ T cells, NK cells and macrophages with a decrease of regulatory T cells (Tregs) in the brain tumor area. Survival of GBM-bearing mice treated with NIC combination is significantly longer compared to animals treated with single checkpoint inhibitor-bearing NICs or free a-CTLA-4 and a-PD-1. Our study demonstrates trans-BBB delivery of tumor-targeted polymer-conjugated checkpoint inhibitors as an effective GBM treatment via activation of both systemic and local privileged brain tumor immune response.


Assuntos
Antineoplásicos Imunológicos/administração & dosagem , Neoplasias Encefálicas/tratamento farmacológico , Glioma/tratamento farmacológico , Imunoconjugados/administração & dosagem , Nanoconjugados/química , Animais , Antineoplásicos Imunológicos/farmacocinética , Biopolímeros/química , Barreira Hematoencefálica/metabolismo , Neoplasias Encefálicas/imunologia , Neoplasias Encefálicas/patologia , Antígeno CTLA-4/antagonistas & inibidores , Antígeno CTLA-4/imunologia , Linhagem Celular Tumoral/transplante , Modelos Animais de Doenças , Feminino , Glioma/imunologia , Glioma/patologia , Humanos , Imunoconjugados/química , Imunoconjugados/farmacocinética , Malatos/química , Camundongos , Permeabilidade , Physarum polycephalum/química , Polímeros/química , Receptor de Morte Celular Programada 1/antagonistas & inibidores , Receptor de Morte Celular Programada 1/imunologia , Resultado do Tratamento
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