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1.
Artigo em Inglês | MEDLINE | ID: mdl-38630575

RESUMO

ZCCHC17 is a master regulator of synaptic gene expression and has recently been shown to play a role in splicing of neuronal mRNA. We previously showed that ZCCHC17 protein declines in Alzheimer's disease (AD) brain tissue before there is significant gliosis and neuronal loss, that ZCCHC17 loss partially replicates observed splicing abnormalities in AD brain tissue, and that maintenance of ZCCHC17 levels is predicted to support cognitive resilience in AD. Here, we assessed the functional consequences of reduced ZCCHC17 expression in primary cortical neuronal cultures using siRNA knockdown. Consistent with its previously identified role in synaptic gene expression, loss of ZCCHC17 led to loss of synaptic protein expression. Patch recording of neurons shows that ZCCHC17 loss significantly disrupted the excitation/inhibition balance of neurotransmission, and favored excitatory-dominant synaptic activity as measured by an increase in spontaneous excitatory post synaptic currents and action potential firing rate, and a decrease in spontaneous inhibitory post synaptic currents. These findings are consistent with the hyperexcitable phenotype seen in AD animal models and in patients. We are the first to assess the functional consequences of ZCCHC17 knockdown in neurons and conclude that ZCCHC17 loss partially phenocopies AD-related loss of synaptic proteins and hyperexcitability.

2.
Cell Rep ; 43(4): 113975, 2024 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-38507411

RESUMO

The intestine is a highly metabolic tissue, but the metabolic programs that influence intestinal crypt proliferation, differentiation, and regeneration are still emerging. Here, we investigate how mitochondrial sirtuin 4 (SIRT4) affects intestinal homeostasis. Intestinal SIRT4 loss promotes cell proliferation in the intestine following ionizing radiation (IR). SIRT4 functions as a tumor suppressor in a mouse model of intestinal cancer, and SIRT4 loss drives dysregulated glutamine and nucleotide metabolism in intestinal adenomas. Intestinal organoids lacking SIRT4 display increased proliferation after IR stress, along with increased glutamine uptake and a shift toward de novo nucleotide biosynthesis over salvage pathways. Inhibition of de novo nucleotide biosynthesis diminishes the growth advantage of SIRT4-deficient organoids after IR stress. This work establishes SIRT4 as a modulator of intestinal metabolism and homeostasis in the setting of DNA-damaging stress.


Assuntos
Proliferação de Células , Neoplasias Intestinais , Intestinos , Sirtuínas , Animais , Humanos , Camundongos , Glutamina/metabolismo , Homeostase , Mucosa Intestinal/metabolismo , Neoplasias Intestinais/metabolismo , Neoplasias Intestinais/patologia , Neoplasias Intestinais/genética , Intestinos/metabolismo , Intestinos/patologia , Camundongos Endogâmicos C57BL , Proteínas Mitocondriais , Nucleotídeos/metabolismo , Organoides/metabolismo , Sirtuínas/metabolismo
3.
Heliyon ; 10(1): e23663, 2024 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-38187266

RESUMO

SCN4A mutations have been shown to be associated with myotonia, paramyotonia congenita, and periodic paralyses. More recently, loss-of-function variants in the SCN4A gene were also noted to be associated with rarer, autosomal recessive forms of congenital myasthenic syndrome and congenital myopathy. Diagnosis is challenging as the initial clinical presentation and histological features on muscle biopsies are non-specific. We report a Han Chinese patient presented with congenital myopathy with two missense SCN4A variants. The patient had an antenatal history of reduced fetal movements, polyhydramnios and a very preterm birth. At birth, she was noted to have low Apgar score, respiratory distress syndrome and hypotonia. Delayed motor development was noted in early childhood. Dysmorphic features such as an elongated face, dolichocephaly and high arched palate were present. At 16 years of age, the patient developed progressive muscle weakness and was wheelchair-bound by age 20. Muscle biopsy revealed non-specific changes only. Targeted hereditary myopathy panel testing by next generation sequencing revealed two previously unreported missense variants c.1841A > T p.(Asn614Ile) and c.4420G > A p.(Ala1474Thr) in the SCN4A gene. The clinical features of SCN4A-related congenital myopathy and myasthenic syndrome were reviewed. This case exemplifies the utility of next generation sequencing in the diagnosis of undifferentiated muscle disease.

4.
J Neurosci ; 44(3)2024 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-38050142

RESUMO

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


Assuntos
Doença de Alzheimer , Resiliência Psicológica , Feminino , Humanos , Masculino , Doença de Alzheimer/metabolismo , Cognição , Neurônios/metabolismo , RNA , Splicing de RNA/genética , Proteínas tau/metabolismo
5.
Clin Transl Med ; 13(10): e1391, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37759102

RESUMO

BACKGROUND: Lung cancer remains the major cause of cancer-related deaths worldwide. Early stages of lung cancer are characterized by long asymptomatic periods that are ineffectively identified with the current screening programs. This deficiency represents a lost opportunity to improve the overall survival of patients. Serum biomarkers are among the most effective strategies for cancer screening and follow up. METHODS: Using bead-based multiplexing assays we screened plasma and tumours of the KrasG12D/+; Lkb1f/f (KL) mouse model of lung cancer for cytokines that could be used as biomarkers. We identified tissue inhibitor of metalloproteinase 1 (TIMP1) as an early biomarker and validated this finding in the plasma of lung cancer patients. We used immunohistochemistry (IHC), previously published single-cell RNA-seq and bulk RNA-seq data to assess the source and expression of TIMP1in the tumour. The prognostic value of TIMP1 was assessed using publicly available human proteomic and transcriptomic databases. RESULTS: We found that TIMP1 is a tumour-secreted protein with high sensitivity and specificity for aggressive cancer, even at early stages in mice. We showed that TIMP1 levels in the tumour and serum correlate with tumour burden and worse survival in mice. We validated this finding using clinical samples from our institution and publicly available human proteomic and transcriptomic databases. These data support the finding that high tumour expression of TIMP1 correlates with an unfavorable prognosis in lung cancer patients. CONCLUSION: TIMP1 is a suitable biomarker for lung cancer detection.


Assuntos
Neoplasias Pulmonares , Inibidor Tecidual de Metaloproteinase-1 , Humanos , Animais , Camundongos , Inibidor Tecidual de Metaloproteinase-1/genética , Proteômica , Prognóstico , Biomarcadores , Neoplasias Pulmonares/diagnóstico , Neoplasias Pulmonares/genética , Proteínas de Neoplasias
6.
bioRxiv ; 2023 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-36993746

RESUMO

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

7.
BMC Public Health ; 22(1): 2164, 2022 11 24.
Artigo em Inglês | MEDLINE | ID: mdl-36424569

RESUMO

BACKGROUND: Peer-research is steered and conducted by people with lived experience of the issues being researched. This paper explores the value of peer-research in two complex public health intervention evaluations in the UK. METHODS: Reports from 18 peer research projects, completed by residents from 12 communities in the UK taking part in two community empowerment interventions, were analysed using cross-case analysis. RESULTS: Undertaking peer research helped to build the evaluation and research skills within individual projects as well as providing data on other outcomes related to the programmes Theory of Change. Some peer researchers, however, felt unprepared for the activity despite support from the academic team and were unsatisfied with project outcomes. While peer research projects provided more opportunities for local residents to engage with the overall evaluations, there was an overreliance on people closely connected to the programmes to be peer researchers. The peer research projects explored topics that were broader than the aims and objectives of the overall programme evaluations. All provided insight into the context in which projects occurred, while some also informed understanding of programme change mechanisms. CONCLUSIONS: Including peer research as part of complex public health intervention evaluations can help uncover important contextual and ecological details beyond the reach of more traditional evaluation data collection. Peer research can also empower and build research/evaluation capacity within communities, which is particularly pertinent for community empowerment interventions.


Assuntos
Grupo Associado , Saúde Pública , Humanos , Avaliação de Programas e Projetos de Saúde , Pesquisadores , Reino Unido
8.
J Allergy Clin Immunol Pract ; 10(6): 1622-1634.e4, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35381395

RESUMO

BACKGROUND: Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection in patients with predominant antibody deficiency (PAD) is associated with high morbidity, yet data regarding the response to SARS-CoV-2 immunization in PAD patients, including additional dose vaccine, are limited. OBJECTIVE: To characterize antibody response to SARS-CoV-2 vaccine in PAD patients and define correlates of vaccine response. METHODS: We assessed the levels and function of anti-SARS-CoV-2 antibodies in 62 PAD patients compared with matched healthy controls at baseline, at 4 to 6 weeks after the initial series of immunization (a single dose of Ad26.COV2.S [Janssen] or two doses of BNT162b2 [Pfizer-BioNTech] or mRNA-1273 [Moderna]), and at 4 to 6 weeks after an additional dose immunization, if received. RESULTS: After the initial series of SARS-CoV-2 vaccination, PAD patients had lower mean anti-spike antibody levels compared with matched healthy controls (140.1 vs 547.3 U/mL; P = .02). Patients with secondary PAD (eg, B-cell depletion therapy was used) and those with severe primary PAD (eg, common variable immunodeficiency with autoinflammatory complications) had the lowest mean anti-spike antibody levels. Immune correlates of a low anti-spike antibody response included low CD4+ T helper cells, low CD19+ total B cells, and low class-switched memory (CD27+IgD/M-) B cells. In addition, a low (<100 U/mL) anti-spike antibody response was associated with prior exposure to B-cell depletion therapy, both at any time in the past (odds ratio = 5.5; confidence interval, 1.5-20.4; P = .01) and proximal to vaccination (odds ratio = 36.4; confidence interval, 1.7-791.9; P = .02). Additional dose immunization with an mRNA vaccine in a subset of 31 PAD patients increased mean anti-spike antibody levels (76.3 U/mL before to 1065 U/mL after the additional dose; P < .0001). CONCLUSIONS: Patients with secondary and severe primary PAD, characterized by low T helper cells, low B cells, and/or low class-switched memory B cells, were at risk for low antibody response to SARS-CoV-2 immunization, which improved after an additional dose vaccination in most patients.


Assuntos
COVID-19 , Vacinas Virais , Ad26COVS1 , Vacina BNT162 , COVID-19/epidemiologia , COVID-19/prevenção & controle , Vacinas contra COVID-19 , Humanos , SARS-CoV-2 , Vacinas Sintéticas , Vacinas de mRNA
9.
J Exp Clin Cancer Res ; 41(1): 43, 2022 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-35093151

RESUMO

BACKGROUND: Targeting mitochondrial oncoproteins presents a new concept in the development of effective cancer therapeutics. ATAD3A is a nuclear-encoded mitochondrial enzyme contributing to mitochondrial dynamics, cholesterol metabolism, and signal transduction. However, its impact and underlying regulatory mechanisms in cancers remain ill-defined. METHODS: We used head and neck squamous cell carcinoma (HNSCC) as a research platform and achieved gene depletion by lentiviral shRNA and CRISPR/Cas9. Molecular alterations were examined by RNA-sequencing, phospho-kinase profiling, Western blotting, RT-qPCR, immunohistochemistry, and immunoprecipitation. Cancer cell growth was assessed by MTT, colony formation, soft agar, and 3D cultures. The therapeutic efficacy in tumor development was evaluated in orthotopic tongue tumor NSG mice. RESULTS: ATAD3A is highly expressed in HNSCC tissues and cell lines. Loss of ATAD3A expression suppresses HNSCC cell growth and elicits tumor regression in orthotopic tumor-bearing mice, whereas gain of ATAD3A expression produces the opposite effects. From a mechanistic perspective, the tumor suppression induced by the overexpression of the Walker A dead mutant of ATAD3A (K358) produces a potent dominant-negative effect due to defective ATP-binding. Moreover, ATAD3A binds to ERK1/2 in the mitochondria of HNSCC cells in the presence of VDAC1, and this interaction is essential for the activation of mitochondrial ERK1/2 signaling. Most importantly, the ATAD3A-ERK1/2 signaling axis drives HNSCC development in a RAS-independent fashion and, thus, tumor suppression is more effectively achieved when ATAD3A knockout is combined with RAS inhibitor treatment. CONCLUSIONS: These findings highlight the novel function of ATAD3A in regulating mitochondrial ERK1/2 activation that favors HNSCC development. Combined targeting of ATAD3A and RAS signaling may potentiate anticancer activity for HNSCC therapeutics.


Assuntos
ATPases Associadas a Diversas Atividades Celulares/metabolismo , Sistema de Sinalização das MAP Quinases/genética , Mitocôndrias/metabolismo , Proteínas Mitocondriais/metabolismo , Carcinoma de Células Escamosas de Cabeça e Pescoço/genética , Animais , Linhagem Celular Tumoral , Proliferação de Células , Humanos , Camundongos , Camundongos Endogâmicos NOD , Transdução de Sinais , Carcinoma de Células Escamosas de Cabeça e Pescoço/patologia
11.
J Diabetes Complications ; 35(8): 107967, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34099384

RESUMO

OBJECTIVE: To explore predictors of severe COVID-19 disease in patients with diabetes hospitalized for COVID-19. METHODS: This is a retrospective observational study of adults with diabetes admitted for COVID-19. Bivariate tests and multivariable Cox regression were used to identify risk factors for severe COVID-19, defined as a composite endpoint of intensive care unit admission/intubation or in-hospital death. RESULTS: In 1134 patients with diabetes admitted for COVID-19, more severe disease was associated with older age (HR 1.02, p<0.001), male sex (HR 1.28, p=0.017), Asian race (HR 1.34, p=0.029 [reference: white]), and greater obesity (moderate obesity HR 1.59, p=0.015; severe obesity HR 2.07, p=0.002 [reference: normal body mass index]). Outpatient diabetes medications were not associated with outcomes. CONCLUSIONS: Age, male sex, Asian race, and obesity were associated with increased risk of severe COVID-19 disease in adults with type 2 diabetes hospitalized for COVID-19. SUMMARY: In patients with type 2 diabetes hospitalized for COVID-19 disease, we observed that age, male sex, Asian race, and obesity predicted severe COVID-19 outcomes of intensive care unit admission, intubation, or in-hospital death. The risk conferred by obesity increased with worsening obesity. Outpatient diabetes medications were not observed to be significant predictors of study outcomes.


Assuntos
COVID-19/diagnóstico , COVID-19/epidemiologia , Diabetes Mellitus Tipo 2/diagnóstico , Diabetes Mellitus Tipo 2/epidemiologia , Admissão do Paciente/estatística & dados numéricos , Adulto , Idoso , Idoso de 80 Anos ou mais , Índice de Massa Corporal , COVID-19/patologia , COVID-19/terapia , Comorbidade , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/terapia , Feminino , Humanos , Unidades de Terapia Intensiva/estatística & dados numéricos , Masculino , Pessoa de Meia-Idade , New York/epidemiologia , Obesidade/complicações , Obesidade/diagnóstico , Obesidade/epidemiologia , Obesidade/terapia , Prognóstico , Grupos Raciais/estatística & dados numéricos , Estudos Retrospectivos , Fatores de Risco , SARS-CoV-2/fisiologia , Índice de Gravidade de Doença
12.
J Biomed Mater Res B Appl Biomater ; 109(12): 2117-2130, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-33983681

RESUMO

The principal cause of cancer deaths is the residual disease, which eventually results in metastases. Certain metastases are induced by disseminated dormancy-capable single cancer cells that can reside within the body undetected for months to years. Awakening of the dormant cells starts a cascade resulting in the patient's demise. Despite its established clinical significance, dormancy research and its clinical translation have been hindered by lack of in vitro models that can identify, isolate, and analyze dormancy-capable cells. We have previously shown that immobilization of cells in a stiff microenvironment induces dormancy in dormancy-capable cell lines. In this communication, we present a novel biomaterial and an in vitro immobilization method to isolate, analyze, and efficiently recover dormancy-capable cancer cells. MCF-7, MDA-MB-231, and MDA-MB-468 cells were individually coated with agarose using a microfluidic flow-focusing device. Coated cells were then immobilized in a rigid and porous silica gel. Dormancy induction by this process was validated by decreased Ki-67 expression, increased p38/ERK activity ratio, and reduced expression of CDK-2, cyclins D1, and E1. We showed that we can reliably and repeatedly induce dormancy in dormancy-capable MCF-7 cells and enhance the dormancy-capable sub-population in MDA-MB-231 cells. As expected, dormancy-resistant MDA-MB-468 cells did not survive immobilization. The dormant cells could be awakened on demand, by digesting the agarose gel in situ, and efficiently recovered by magnetically separating the silica gel, making the cells available for downstream analysis and testing. The awakened cells were shown to regain motility immediately, proliferating, and migrating normally.


Assuntos
Materiais Biocompatíveis , Neoplasias , Humanos , Células MCF-7 , Neoplasias/metabolismo , Sefarose/farmacologia , Dióxido de Silício/farmacologia
13.
Skeletal Radiol ; 50(6): 1219-1225, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33009582

RESUMO

OBJECTIVE: To describe the technique of sonographic ulnar nerve mapping in the postoperative elbow for surgical planning. MATERIALS AND METHODS: A retrospective review of a surgical databank identified 24 patients, all aged 18 years and older with a history of orthopedic elbow surgery, who were referred for preoperative sonographic mapping of the ulnar nerve prior to subsequent surgery. All cases were reviewed for patient demographics, clinical presentation, prior surgical interventions, and ultrasound technique. Charts were reviewed for intraoperative and postoperative outcomes, including nerve injury. RESULTS: The cohort included 12 males and 12 females with a mean age of 51 years (range 22-68 years) and a mean BMI of 29 (range 20-48). Preoperative sonographic ulnar nerve mapping occurred following various elbow surgeries including ulnar nerve transposition to assess nerve location prior to subsequent elbow surgery. Of the 24 patients with preoperative sonographic ulnar nerve mapping, subsequent surgery was performed arthroscopically in 14 and open in 10 cases. In 11 of the 24 cases, there was specific mention of a modified approach to joint access which was guided by the ulnar nerve map. There were no perioperative ulnar nerve-related complications, such as nerve transection. CONCLUSION: Preoperative mapping can facilitate planning of surgical access and ulnar nerve dissection. Sonographic mapping of the ulnar nerve reduces the potential uncertainty of nerve palpation in a complex postoperative elbow following ulnar nerve transposition. This technique may mitigate the risk of ulnar nerve injury.


Assuntos
Articulação do Cotovelo , Procedimentos Ortopédicos , Adulto , Idoso , Descompressão Cirúrgica , Cotovelo , Articulação do Cotovelo/diagnóstico por imagem , Articulação do Cotovelo/cirurgia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Nervo Ulnar/diagnóstico por imagem , Nervo Ulnar/cirurgia , Adulto Jovem
14.
Innovations (Phila) ; 15(4): 322-328, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32830573

RESUMO

OBJECTIVE: Cable closure has been introduced as a potential alternative to traditional wire cerclage (WC) for closure of median sternotomy. To evaluate whether cable closure improves patient outcomes, we conducted a systematic review and meta-analysis of the literature. METHODS: Ovid versions of Medline and Embase, and Google Scholar were used for the literature search. This yielded 7 studies (n = 2,758), which compared traditional WC to cable closure systems. Outcomes included deep sternal wound infection, sternal dehiscence, postoperative pain score, and sternal wound infection. RESULTS: We found significantly lower incidence of sternal dehiscence for cable closure compared to WC (risk ratio [RR] 0.14, 95% confidence interval [CI]: 0.03 to 0.59, P < 0.01, I 2 = 0%) but no difference in DSWI (RR 0.97, 95% CI: 0.39 to 2.42, P = 0.95, I 2 = 33%). Cable closure was also associated with lower pain when compared with the WC group (mean difference -1.04 points, 95% CI: -1.89 to -0.19, P = 0.02, I 2 = 87%). CONCLUSIONS: This study suggests that cable closure results in less incidence of sternal dehiscence and pain compared to WC. Nonetheless, there remains a limited number of studies on this topic and further high-quality studies are required to confirm the results of this meta-analysis.


Assuntos
Esternotomia/métodos , Técnicas de Fechamento de Ferimentos/instrumentação , Fios Ortopédicos , Humanos , Incidência , Dor Pós-Operatória/epidemiologia , Dor Pós-Operatória/prevenção & controle , Ensaios Clínicos Controlados Aleatórios como Assunto , Esternotomia/instrumentação , Deiscência da Ferida Operatória/epidemiologia , Deiscência da Ferida Operatória/prevenção & controle , Infecção da Ferida Cirúrgica/epidemiologia
15.
Biotechnol Bioeng ; 117(10): 3066-3080, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32589792

RESUMO

Around 20-30% of ovarian cancer patients exhibit chemoresistance, but there are currently no methods to predict whether a patient will respond to chemotherapy. Here, we discovered that chemoresistant ovarian cancer cells exhibit enhanced survival in a quiescent state upon experiencing the stress of physical confinement. When immobilized in stiff silica gels, most ovarian cancer cells die within days, but surviving cells exhibit hallmarks of single-cell dormancy. Upon extraction from gels, the cells resume proliferation but demonstrate enhanced viability upon reimmobilization, indicating that initial immobilization selects for cells with a higher propensity to enter dormancy. RNA-seq analysis of the extracted cells shows they have signaling responses similar to cells surviving cisplatin treatment, and in comparison to chemoresistant patient cohorts, they share differentially expressed genes that are associated with platinum-resistance pathways. Furthermore, these extracted cells demonstrate greater resistance to cisplatin and paclitaxel, despite being proliferative. In contrast, serum starvation and hypoxia could not effectively select for chemoresistant cells upon removal of the environmental stress. These findings demonstrate that ovarian cancer chemoresistance and the ability to enter dormancy are linked, and immobilization rapidly distinguishes chemoresistant cells. This platform could be suitable for mechanistic studies, drug development, or as a clinical diagnostic tool.


Assuntos
Bioensaio/métodos , Sobrevivência Celular , Cisplatino/farmacologia , Resistencia a Medicamentos Antineoplásicos , Neoplasias Ovarianas/tratamento farmacológico , Paclitaxel/farmacologia , Sílica Gel/química , Antineoplásicos/farmacologia , Antineoplásicos Fitogênicos/farmacologia , Linhagem Celular Tumoral , Proliferação de Células , Feminino , Humanos , Neoplasias Ovarianas/genética , Neoplasias Ovarianas/metabolismo , Neoplasias Ovarianas/patologia , Transdução de Sinais
16.
Cells ; 9(3)2020 02 25.
Artigo em Inglês | MEDLINE | ID: mdl-32106632

RESUMO

BACKGROUND: Development of radioresistance in oral squamous cell carcinoma (OSCC) remains a significant problem in cancer treatment, contributing to the lack of improvement in survival trends in recent decades. Effective strategies to overcome radioresistance are necessary to improve the therapeutic outcomes of radiotherapy in OSCC patients. METHODS: Cells and xenograft tumors were irradiated using the Small Animal Radiation Research Platform. AKT inhibitor capivasertib (AZD5363) was encapsulated into cathepsin B-responsible nanoparticles (NPs) for tumor-specific delivery. Cell viability was measured by alamarBlue, cell growth was determined by colony formation and 3D culture, and apoptosis was assessed by flow cytometry with the staining of Fluorescein isothiocyanate (FITC) Annexin V and PI. An orthotopic tongue tumor model was used to evaluate the in vivo therapeutic effects. The molecular changes induced by the treatments were assessed by Western blotting and immunohistochemistry. RESULTS: We show that upregulation of AKT signaling is the critical mechanism for radioresistance in OSCC cells, and AKT inactivation by a selective and potent AKT inhibitor capivasertib results in radiosensitivity. Moreover, relative to irradiation (IR) alone, IR combined with the delivery of capivasertib in association with tumor-seeking NPs greatly enhanced tumor cell repression in 3D cell cultures and OSCC tumor shrinkage in an orthotopic mouse model. CONCLUSIONS: These data indicate that capivasertib is a potent agent that sensitizes radioresistant OSCC cells to IR and is a promising strategy to overcome failure of radiotherapy in OSCC patients.


Assuntos
Neoplasias Bucais/dietoterapia , Nanopartículas/metabolismo , Proteínas Proto-Oncogênicas c-akt/uso terapêutico , Pirimidinas/uso terapêutico , Pirróis/uso terapêutico , Animais , Modelos Animais de Doenças , Feminino , Humanos , Camundongos , Camundongos Endogâmicos NOD , Neoplasias Bucais/radioterapia , Proteínas Proto-Oncogênicas c-akt/farmacologia , Pirimidinas/farmacologia , Pirróis/farmacologia , Ensaios Antitumorais Modelo de Xenoenxerto
17.
Ann Biomed Eng ; 48(4): 1230-1240, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31916125

RESUMO

Irreversible electroporation (IRE) is an emerging technology for non-thermal ablation of solid tumors. This study sought to integrate electrodes into microporous poly(caprolactone) (PCL) scaffolds previously shown to recruit metastasizing cancer cells in vivo in order to facilitate application of IRE to disseminating cancer cells. As the ideal parallel plate geometry would render much of the porous scaffold surface inaccessible to infiltrating cells, numerical modeling was utilized to predict the spatial profile of electric field strength within the scaffold for alternative electrode designs. Metal mesh electrodes with 0.35 mm aperture and 0.16 mm wire diameter established electric fields with similar spatial uniformity as the parallel plate geometry. Composite PCL-IRE scaffolds were fabricated by placing cylindrical porous PCL scaffolds between two PCL dip-coated stainless steel wire meshes. PCL-IRE scaffolds exhibited no difference in cell infiltration in vivo compared to PCL scaffolds. In addition, upon application of IRE in vivo, cells infiltrating the PCL-IRE scaffolds were successfully ablated, as determined by histological analysis 3 days post-treatment. The ability to establish homogeneous electric fields within a biomaterial that can recruit metastatic cancer cells, especially when combined with immunotherapy, may further advance IRE technology beyond solid tumors to the treatment of systemic cancer.


Assuntos
Materiais Biocompatíveis , Eletroporação , Poliésteres , Animais , Linhagem Celular Tumoral , Condutividade Elétrica , Eletrodos , Feminino , Melanoma Experimental/terapia , Camundongos Endogâmicos C57BL
18.
Int J Hyperthermia ; 36(1): 130-138, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30676126

RESUMO

Focal thermal therapy (Heat), cryosurgery (Cryo) and irreversible electroporation (IRE) are increasingly used to treat cancer. However, local recurrence and systemic spread are persistent negative outcomes. Nevertheless, emerging work with immunotherapies (i.e., checkpoint blockade or dendritic cell (DC) vaccination) in concert with focal therapies may improve outcomes. To understand the role of focal therapy in priming the immune system for immunotherapy, an in vitro model of T cell response after exposure to B16 melanoma cell lysates after lethal exposures was designed. Exposure included: Heat (50 °C, 30 min), Cryo (-80 °C, 30 min) and IRE (1250 V/cm, 99 pulses, 50 µs pulses with 1 Hz intervals). After viability assessment (CCK-8 assay), cell lysates were collected and assessed for protein release (BCA assay), protein denaturation (FTIR-spectroscopy), TRP-2 antigen release (western blot), and T cell activation (antigen-specific CD8 T cell proliferation). Results showed IRE released the most protein and antigen (TRP-2), followed by Cryo and Heat. In contrast, Cryo released the most native (not denatured) protein, compared to IRE and Heat. Finally, IRE dramatically outperformed both Cryo and Heat in T cell activation while Cryo modestly outperformed Heat. This study demonstrates that despite all focal therapies ability to destroy cells, the 'quantity' (i.e., amount) and 'quality' (i.e., molecular state) of tumor protein (including antigen) released can dramatically change the ensuing priming of the immune system. This suggests protein-based metrics whereby focal therapies can be designed to prime the immune system in concert with immunotherapies to eventually achieve improved and durable cancer treatment in vivo.


Assuntos
Antígenos de Neoplasias/metabolismo , Linfócitos T CD8-Positivos/imunologia , Neoplasias/imunologia , Animais , Humanos , Camundongos , Camundongos Transgênicos
19.
J Soc Psychol ; 159(3): 284-298, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-29634454

RESUMO

Previous research shows that people with high self-esteem cope with threats to the self by reducing the extent to which their self-worth is contingent on the threatened domain (Buckingham, Weber, & Sypher, 2012). The present studies tested the hypothesis that this is a defensive process. In support of this hypothesis, Study 1 (N = 160), showed that self-affirmation attenuates the tendency for people with high self-esteem to reduce their contingencies of self-worth following self-threat. Furthermore, Study 2 (N = 286), showed that this tendency was more prevalent among people with defensive self-esteem than among those with secure self-esteem. The present studies imply that reducing contingent self-worth after self-threat is a defensive process. We discuss implications for theories of contingent self-worth.


Assuntos
Adaptação Psicológica , Mecanismos de Defesa , Autoimagem , Adulto , Feminino , Humanos , Masculino , Adulto Jovem
20.
Pain ; 159(7): 1325-1345, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29561359

RESUMO

Molecular neurobiological insight into human nervous tissues is needed to generate next-generation therapeutics for neurological disorders such as chronic pain. We obtained human dorsal root ganglia (hDRG) samples from organ donors and performed RNA-sequencing (RNA-seq) to study the hDRG transcriptional landscape, systematically comparing it with publicly available data from a variety of human and orthologous mouse tissues, including mouse DRG (mDRG). We characterized the hDRG transcriptional profile in terms of tissue-restricted gene coexpression patterns and putative transcriptional regulators, and formulated an information-theoretic framework to quantify DRG enrichment. Relevant gene families and pathways were also analyzed, including transcription factors, G-protein-coupled receptors, and ion channels. Our analyses reveal an hDRG-enriched protein-coding gene set (∼140), some of which have not been described in the context of DRG or pain signaling. Most of these show conserved enrichment in mDRG and were mined for known drug-gene product interactions. Conserved enrichment of the vast majority of transcription factors suggests that the mDRG is a faithful model system for studying hDRG, because of evolutionarily conserved regulatory programs. Comparison of hDRG and tibial nerve transcriptomes suggests trafficking of neuronal mRNA to axons in adult hDRG, and are consistent with studies of axonal transport in rodent sensory neurons. We present our work as an online, searchable repository (https://www.utdallas.edu/bbs/painneurosciencelab/sensoryomics/drgtxome), creating a valuable resource for the community. Our analyses provide insight into DRG biology for guiding development of novel therapeutics and a blueprint for cross-species transcriptomic analyses.


Assuntos
Gânglios Espinais/metabolismo , Dor/metabolismo , Transcriptoma , Animais , Sequência de Bases , Perfilação da Expressão Gênica , Humanos , Camundongos , Neurociências , Dor/genética
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