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2.
In Silico Biol ; 13(1-2): 41-53, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31156157

RESUMO

Global level network analysis of molecular links is necessary for systems level view of complex diseases like cancer. Using genome-wide expression datasets, we constructed and compared gene co-expression based specific networks of pre-cancerous tumors (adenoma) and cancerous tumors (carcinoma) with paired normal networks to assess for any possible changes in network connectivity. Previously, loss of connectivity was reported as a characteristics of cancer samples. Here, we observed that pre-cancerous conditions also had significantly less connections than paired normal samples. We observed a loss of connectivity trend for colorectal adenoma, aldosterone producing adenoma and uterine leiomyoma. We also showed that the loss of connectivity trend is not specific to positive or negative correlation based networks. Differential hub genes, which were the most highly differentially less connected genes in tumor, were mostly different between different datasets. No common gene list could be defined which underlies the lower connectivity of tumor specific networks. Connectivity of colorectal cancer methylation targets was different from other genes. Extracellular space related terms were enriched in negative correlation based differential hubs and common methylation targets of colorectal carcinoma. Our results indicate a systems level change of lower connectivity as cells transform to not only cancer but also pre-cancerous conditions. This systems level behavior could not be attributed to a group of genes.

3.
PLoS One ; 14(5): e0216521, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31051009

RESUMO

AIM: Christchurch, New Zealand, experienced two major earthquakes on 4th September 2010 and 22nd February 2011. Previous studies have demonstrated that earthquakes are associated with sudden cardiac deaths. Whilst myocardial ischemia would contribute to this, ventricular arrhythmia triggered by stress has also been suggested. We aim to study the impact of the two earthquakes on ventricular arrhythmia events. METHODS: We conducted a retrospective review of all patients resident in the earthquake zone with implantable defibrillators. Ventricular arrhythmia requiring therapy and non-sustained events were recorded from the period of 30 days before thru 30 days after the two earthquakes. Weekly event rates were calculated and compared using log rank analysis. Results are expressed as mean (range), significance was determined at the <0.05 level. RESULTS: For the 211 patients who were exposed to the 2010 earthquake, there was no difference in the proportion of patients free of therapy, either Shock or ATP (0.943 before and 0.933 after the earthquake, p = 0.85, ns). Similarly, there was no significant increase in events requiring therapy in the 236 patients exposed to the 2011 earthquake (0.957 before and 0.961 after the earthquake, p = 0.80, ns). We identified one patient who required multiple therapy for ventricular tachycardia immediately following both earthquakes. CONCLUSION: The two Christchurch earthquakes were not associated with an increase in the event rate of either sustained or non-sustained ventricular arrhythmias in our patients. We identified only a single patient who had arrhythmic storms immediately following the earthquakes.

4.
BMJ Open ; 9(5): e025253, 2019 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-31061024

RESUMO

OBJECTIVES: In takotsubo syndrome, QTc prolongation is a measure of risk of potentially fatal arrhythmia. It is not known how this risk, or derangement of other markers, differs across the echo variants of takotsubo syndrome. Therefore, we sought to explore whether apical takotsubo syndrome differs from the variants of the syndrome in more ways than just regional wall motion pattern. As the region of affected myocardium is usually larger, we hypothesised that patients with the classic apical ballooning form of takotsubo syndrome would have more severe derangement of their markers. DESIGN: Observational study of patients gathered from a prospective database (2010-2018) and by retrospective review (2006-2009). SETTING: The sole tertiary hospital from a New Zealand region in which case clusters of takotsubo syndrome were precipitated by large earthquakes in 2010, 2011 and 2016. PARTICIPANTS: A total of 222 patients who met a modified version of the Mayo criteria for takotsubo syndrome were included. All patients had digitally archived echocardiograms that were over-read by a second echocardiologist blinded to the clinical report. PRIMARY OUTCOME MEASURES: Ejection fraction, peak troponin and QTc interval. RESULTS: Patients with the apical form were older (p=0.011), had a lower initial left ventricular ejection fraction (35% vs 44%, p<0.0001) and a higher peak high-sensitivity troponin I (hsTnI) (p=0.01) than those with variant forms. There was no difference in the electrical abnormalities between the variants (QTc interval, heart rate, PR interval, QRS duration or T-wave axis). There was also no correlation between any of peak hsTnI, peak QTc and ejection fraction. QTc interval increased on day 2 and peaked on day 3 before falling steeply (p<0.0001). CONCLUSIONS: The variants of takotsubo syndrome differ in more ways than just their echo pattern but do not differ in their electrical abnormalities. There is a dissociation between the structural and electrical abnormalities. QTc peaks on day 3 and then falls steeply.

5.
Biomaterials ; 210: 94-104, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31060867

RESUMO

Though early detection and treatment of primary tumors has significantly improved in recent years, metastatic disease remains among the most significant challenges in cancer therapy. Cancer cells can disseminate before the primary tumor is detected to form micro or gross metastases, requiring toxic systemic therapies. To prevent and suppress metastases, we have developed a nontoxic, long-circulating nanoscale coordination polymer (NCP) protecting microRNA (miRNA) in circulation and releasing it in tumors. PtIV(en)2 [en = ethylenediamine] containing NCPs (PtEN) can release a nontoxic, kinetically inert PtII(en)2 compound and carbon dioxide which aids the endosomal escape of its miRNA cargo, miR-655-3p. Without the presence of the PtEN core, the miRNA showed cellular uptake but no effect. When transfected into human colorectal HCT116 cells by NCPs, this oligometastatic miRNA limited proliferation and epithelial-to-mesenchymal transition by preventing ß-catenin nuclear translocation and tumor cell invasion. Systemic administrations of PtEN/miR-655-3p sustained effective transfection to reduce liver colonization and tumor burden in a xenogenic hepatic metastatic model of HCT116 without any observable toxicity.

6.
Methods Mol Biol ; 1974: 41-56, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31098994

RESUMO

In RNA interference (RNAi), silencing is achieved through the interaction of double-stranded small interfering RNAs (siRNAs) with essential RNAi pathway proteins, including Argonaute 2 (Ago2). Based on these interactions, one strand of the siRNA is loaded into Ago2 forming the active RNA-induced silencing complex (RISC). Optimal siRNAs maximize RISC activity against the intended target and minimize off-target silencing. To achieve the desired activity and specificity, selection of the appropriate siRNA strand for loading into Ago2 is essential. Here, we provide a protocol to quantify the relative loading of individual siRNA strands into Ago2, one factor in determining the capacity of a siRNA to achieve silencing activity and target specificity.

7.
Nat Commun ; 10(1): 1899, 2019 04 23.
Artigo em Inglês | MEDLINE | ID: mdl-31015397

RESUMO

Nanoparticles can potentially stimulate tumour microenvironments to elicit antitumour immunity. Herein, we demonstrate effective immunotherapy of colorectal cancer via systemic delivery of an immunostimulatory chemotherapeutic combination in nanoscale coordination polymer (NCP) core-shell particles. Oxaliplatin and dihydroartemesinin have contrasting physicochemical properties but strong synergy in reactive oxygen species (ROS) generation and anticancer activity. The combined ROS generation is harnessed for immune activation to synergize with an anti-PD-L1 antibody for the treatment of murine colorectal cancer tumours. The favourable biodistribution and tumour uptake of NCPs and the absence of peripheral neuropathy allow for repeated dosing to afford 100% tumour eradication. The involvement of innate and adaptive immune systems elicit strong and long lasting antitumour immunity which prevents tumour formation when cured mice are challenged with cancer cells. The intrinsically biodegradable, well tolerated, and systemically available immunostimulatory NCP promises to enter clinical testing as an immunotherapy against colorectal cancer.


Assuntos
Adenocarcinoma/terapia , Vacinas Anticâncer/farmacologia , Neoplasias Colorretais/terapia , Fatores Imunológicos/farmacologia , Nanopartículas/administração & dosagem , Polímeros/administração & dosagem , Imunidade Adaptativa/efeitos dos fármacos , Adenocarcinoma/genética , Adenocarcinoma/imunologia , Adenocarcinoma/mortalidade , Animais , Anticorpos Neutralizantes/farmacologia , Antineoplásicos/farmacocinética , Antineoplásicos/farmacologia , Artemisininas/farmacocinética , Artemisininas/farmacologia , Antígeno B7-H1/antagonistas & inibidores , Antígeno B7-H1/genética , Antígeno B7-H1/imunologia , Vacinas Anticâncer/síntese química , Vacinas Anticâncer/farmacocinética , Linhagem Celular Tumoral , Neoplasias Colorretais/genética , Neoplasias Colorretais/imunologia , Neoplasias Colorretais/mortalidade , Composição de Medicamentos/métodos , Humanos , Imunidade Inata/efeitos dos fármacos , Fatores Imunológicos/síntese química , Fatores Imunológicos/farmacocinética , Camundongos , Camundongos Endogâmicos BALB C , Nanopartículas/química , Transplante de Neoplasias , Oxaliplatina/farmacocinética , Oxaliplatina/farmacologia , Polímeros/síntese química , Ratos , Ratos Sprague-Dawley , Espécies Reativas de Oxigênio/agonistas , Espécies Reativas de Oxigênio/imunologia , Espécies Reativas de Oxigênio/metabolismo , Análise de Sobrevida , Microambiente Tumoral/efeitos dos fármacos , Microambiente Tumoral/imunologia
8.
Cell Rep ; 27(1): 307-320.e5, 2019 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-30943411

RESUMO

Activation of inositol-requiring enzyme (IRE1α) is an indispensable step in remedying the cellular stress associated with lipid perturbation in the endoplasmic reticulum (ER) membrane. IRE1α is a single-spanning ER transmembrane protein possessing both kinase and endonuclease functions, and its activation can be fully achieved through the dimerization and/or oligomerization process. How IRE1α senses membrane lipid saturation remains largely unresolved. Using both computational and experimental tools, we systematically investigated the dimerization process of the transmembrane domain (TMD) of IRE1α and found that, with help of the serine 450 residue, the conserved tryptophan 457 residue buttresses the core dimerization interface of IRE1α-TMD. BiFC (bimolecular fluorescence complementation) experiments revealed that mutation on these residues abolished the saturated fatty acid-induced dimerization in the ER membrane and subsequently inactivated IRE1α activity in vivo. Therefore, our results suggest that the structural elements of IRE1α-TMD serve as a key sensor that detects membrane aberrancy.

9.
Sci Rep ; 9(1): 2969, 2019 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-30814572

RESUMO

Neural differentiation of mesenchymal stem cells is a controversial phenomenon, as it would require transdifferentiation across the mesoderm-ectoderm barrier. However, several laboratories have observed that MSCs are able to be induced to express neural characteristics. Previously, we demonstrated that the cAMP-elevating agents, forskolin and IBMX, induced neural-like differentiation of MSCs, including expression of neural markers and increased sensitivity to neurotransmitters. However, due to the broad range of effects that forskolin and IBMX can elicit through the intracellular second messenger, cAMP, a better mechanistic understanding is required. Here, we show that neural induction by forskolin and IBMX is dependent on downregulation of expression of the master transcriptional regulator, neuron restrictive silencer factor (NRSF), and its downstream target genes. Since silencing of NRSF is known to initiate neural differentiation, it suggests that forskolin and IBMX result in transdifferentiation of MSCs into a neural lineage.

10.
J Alzheimers Dis ; 2018 Nov 29.
Artigo em Inglês | MEDLINE | ID: mdl-30507579

RESUMO

Little is known about the extracellular matrix (ECM) during progression of AD pathology. Brain ECM is abundant in hyaluronan (HA), a non-sulfated glycosaminoglycan synthesized by HA synthases (HAS) 1-3 in a high molecular weight (MW) form that is degraded into lower MW fragments. We hypothesized that pathologic severity of AD is associated with increases in HA and HA-associated ECM molecules. To test this hypothesis, we assessed HA accumulation and size; HA synthases (HAS) 1-3; and the HA-stabilizing hyaladherin, TSG-6 in parietal cortex samples from autopsied research subjects with not AD (CERAD = 0, Braak = 0- II, n = 12-21), intermediate AD (CERAD = 2, Braak = III-IV, n = 13-18), and high AD (CERAD = 3, Braak = V-VI, n = 32-40) AD neuropathologic change. By histochemistry, HA was associated with deposits of amyloid and tau, and was also found diffusely in brain parenchyma, with overall HA quantity (measured by ELSA) significantly greater in brains with high AD neuropathology. Mean HA MW was similar among the samples. HAS2 and TSG-6 mRNA expression, and TSG-6 protein levels were significantly increased in high AD and both molecules were present in vasculature, NeuN-positive neurons, and Iba1-positive microglia. These results did not change when accounting for gender, advanced age (≥ 90 years versus <90 years), or the clinical diagnosis of dementia. Collectively, our results indicate a positive correlation between HA accumulation and AD neuropathology, and suggest a possible role for HA synthesis and metabolism in AD progression.

12.
Mol Pharm ; 15(11): 4835-4842, 2018 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-30350641

RESUMO

Pharmaceutical excipients are no longer considered inert and have been shown to influence the activity of metabolic enzymes and transporters, resulting in altered pharmacokinetics of substrate drugs. In this study, the effect of 25 excipients commonly used in drug formulations were investigated for their effect on P-glycoprotein (P-gp) activity. The effect of excipients on P-gp were assessed by measuring the change in the cellular accumulation of a P-gp substrate, digoxin, in MDCK-MDR1 (Madin Darby canine kidney transfected with multidrug resistance 1 gene) cells. The cells were exposed to low (10 µM) and high (200 µM) concentrations of excipient along with 10 µM digoxin. Excipient concentrations were chosen to span the range of concentrations previously used for investigating activities in vitro. At 10 µM of excipient, an increase in the intracellular digoxin concentration was seen with d-α-tocopherol poly-(ethylene glycol) succinate (Vit-E-PEG; p = 0.002), poly(ethylene oxide)20 sorbitan monooleate (Tween 80; p = 0.001), cetyltrimethylammonium bromide (CTAB; p = 0.021), poly(ethylene oxide)35 modified castor oil (Cremophor EL; p = 0.01), polyethylene glycol15-hydroxystearate (Solutol HS 15; p = 0.006), and poly(ethylene glycol) hexadecyl ether (Brij 58; p = 0.001). At 200 µM, Vit-E-PEG ( p < 0.0001), sodium 1,4-bis (2-ethylhexoxy)-1,4-dioxobutane-2-sulfonate (AOT; p < 0.0001), Tween 80 ( p < 0.0001), CTAB ( p = 0.004), poly(ethylene oxide)20 sorbitan monolaurate (Tween 20; p < 0.0001), Cremophor EL ( p < 0.0001), Solutol HS 15 ( p < 0.0001), Brij 58 ( p < 0.0001), and sodium carboxymethyl cellulose (NaCMC; p = 0.006) increased intracellular digoxin significantly. Concentration-dependent inhibition of P-gp was then investigated for selected excipients giving an IC50 for Vit-E-PEG (12.48 µM), AOT (192.5 µM), Tween 80 (45.29 µM), CTAB (96.67 µM), Tween 20 (74.15 µM), Cremophor EL (11.92 µM), Solutol HS 15 (179.8 µM), Brij 58 (25.22 µM), and NaCMC (46.69 µM). These data add to the growing body of evidence demonstrating that not all excipients are inert and will aid excipient choice for rational formulation development.

13.
BMJ Qual Saf ; 2018 Oct 08.
Artigo em Inglês | MEDLINE | ID: mdl-30297375

RESUMO

BACKGROUND: Quality improvement (QI) campaigns appear to increase use of evidence-based practices, but their effect on health outcomes is less well studied. OBJECTIVE: To assess the effect of a multistate QI campaign (Project JOINTS, Joining Organizations IN Tackling SSIs) that used the Institute for Healthcare Improvement's Rapid Spread Network to promote adoption of evidence-based surgical site infection (SSI) prevention practices. METHODS: We analysed rates of SSI among Medicare beneficiaries undergoing hip and knee arthroplasty during preintervention (May 2010 to April 2011) and postintervention (November 2011 to September 2013) periods in five states included in a multistate trial of the Project JOINTS campaign and five matched comparison states. We used generalised linear mixed effects models and a difference-in-differences approach to estimate changes in SSI outcomes. RESULTS: 125 070 patients underwent hip arthroplasty in 405 hospitals in intervention states, compared with 131 787 in 525 hospitals in comparison states. 170 663 patients underwent knee arthroplasty in 397 hospitals in intervention states, compared with 196 064 in 518 hospitals in comparison states. After the campaign, patients in intervention states had a 15% lower odds of developing hip arthroplasty SSIs (OR=0.85, 95% CI 0.75 to 0.96, p=0.01) and a 12% lower odds of knee arthroplasty SSIs than patients in comparison states (OR=0.88, 95% CI 0.78 to 0.99, p=0.04). CONCLUSIONS: A larger reduction of SSI rates following hip and knee arthroplasty was shown in intervention states than in matched control states.

14.
Can J Ophthalmol ; 53(4): 342-348, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-30119787

RESUMO

OBJECTIVE: Our prior study revealed significantly lower use of eye care providers in Newfoundland and Labrador (NFLD). This study reports factors associated with this low use and related vision health outcomes. DESIGN: Cross-sectional survey. PARTICIPANTS: A total of 14 925 Caucasian respondents to the Canadian Community Health Survey - Healthy Aging 2008/2009 aged ≥65 years. METHODS: Univariate and multivariate analyses were performed using self-reported survey data. RESULTS: NFLD, along with 3 other provinces, does not insure seniors for routine eye examinations. Among seniors without self-reported glaucoma, cataracts, and diabetes, the use of eye care providers in NFLD (36.3%) is the lowest compared with provinces with (50.7%, p < 0.05) and without (42.2%, p > 0.05) government-insured eye examinations. Among seniors with known eye disease insured for eye care in all provinces, eye care utilisation in NFLD (63.1%) is still the lowest across all provinces (69.4%-71.3%, p > 0.05). Compared with the national average, NFLD seniors have significantly higher proportions of low income (61.7% vs 47.4%), no postsecondary education (53.6% vs 42.2%), and rural residency (40.6% vs 18.9%). These factors are all associated with low levels of eye care utilisation. Compared with insured provinces, NFLD has a significantly lower prevalence of self-reported cataracts (16.7% vs 23.1) and glaucoma (3.8% vs 7.0%), and a slightly higher prevalence of presenting visual impairment (4.0% vs 3.5%). CONCLUSIONS: Lack of government insurance, low socioeconomic status, and living in nonurbanised areas all contribute to the underutilisation of eye care providers in NFLD. This underutilisation appears to be associated with reduced detection of eye diseases.

15.
Respir Res ; 19(1): 146, 2018 08 02.
Artigo em Inglês | MEDLINE | ID: mdl-30071849

RESUMO

BACKGROUND: Airway inflammation is a hallmark of asthma. Alterations in extracellular matrix (ECM) hyaluronan (HA) content have been shown to modulate the recruitment and retention of inflammatory cells. Bronchial epithelial cells (BECs) regulate the activity of human lung fibroblasts (HLFs); however, their contribution in regulating HLF production of HA in asthma is unknown. In this study, we tested the hypothesis that BECs from asthmatic children promote the generation of a pro-inflammatory, HA-enriched ECM by HLFs, which promotes the retention of leukocytes. METHODS: BECs were obtained from well-characterized asthmatic and healthy children ages 6-18 years. HLFs were co-cultured with BECs for 96 h and samples were harvested for analysis of gene expression, synthesis and accumulation of HA, and subjected to a leukocyte adhesion assay with U937 monocytes. RESULTS: We observed increased expression of HA synthases HAS2 and HAS3 in HLFs co-cultured with asthmatic BECs. Furthermore, we demonstrated greater total accumulation and increased synthesis of HA by HLFs co-cultured with asthmatic BECs compared to healthy BEC/HLF co-cultures. ECM generated by HLFs co-cultured with asthmatic BECs displayed increased HA-dependent adhesion of leukocytes in a separate in vitro binding assay. CONCLUSIONS: Our findings demonstrate that BEC regulation of HA production by HLFs is altered in asthma, which may in turn promote the establishment of a more leukocyte-permissive ECM promoting airway inflammation in this disease.


Assuntos
Asma/metabolismo , Brônquios/metabolismo , Matriz Extracelular/metabolismo , Ácido Hialurônico/biossíntese , Leucócitos/metabolismo , Mucosa Respiratória/metabolismo , Adolescente , Brônquios/citologia , Criança , Técnicas de Cocultura , Feminino , Fibroblastos/metabolismo , Humanos , Pulmão/metabolismo , Masculino , Mucosa Respiratória/citologia , Células U937
16.
Artigo em Inglês | MEDLINE | ID: mdl-30016571

RESUMO

Cancer immunotherapies that train or stimulate the inherent immunological systems to recognize, attack, and eradicate tumor cells with minimal damage to healthy cells have demonstrated promising clinical responses in recent years. However, most of these immunotherapeutic strategies only benefit a small subset of patients and cause systemic autoimmune side effects in some patients. Immunogenic cell death (ICD)-inducing modalities not only directly kill cancer cells but also induce antitumor immune responses against a broad spectrum of solid tumors. Such strategies for generating vaccine-like functions could be used to stimulate a "cold" tumor microenvironment to become an immunogenic, "hot" tumor microenvironment, working in synergy with immunotherapies to increase patient response rates and lead to successful treatment outcomes. This Minireview will focus on nanoparticle-based treatment modalities that can induce and enhance ICD to potentiate cancer immunotherapy.

17.
Drug Metab Pharmacokinet ; 33(4): 179-187, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29921509

RESUMO

The first-order degradation rate constant (kdeg) of cytochrome P450 (CYP) enzymes is a known source of uncertainty in the prediction of time-dependent drug-drug interactions (DDIs) in physiologically-based pharmacokinetic (PBPK) modelling. This study aimed to measure CYP kdeg using siRNA to suppress CYP expression in primary human hepatocytes followed by incubation over a time-course and tracking of protein expression and activity to observe degradation. The magnitude of gene knockdown was determined by qPCR and activity was measured by probe substrate metabolite formation and CYP2B6-Glo™ assay. Protein disappearance was determined by Western blotting. During a time-course of 96 and 60 h of incubation, over 60% and 76% mRNA knockdown was observed for CYP3A4 and CYP2B6, respectively. The kdeg of CYP3A4 and CYP2B6 protein was 0.0138 h-1 (±0.0023) and 0.0375 h-1 (±0.025), respectively. The kdeg derived from probe substrate metabolism activity was 0.0171 h-1 (±0.0025) for CYP3A4 and 0.0258 h-1 (±0.0093) for CYP2B6. The CYP3A4 kdeg values derived from protein disappearance and metabolic activity were in relatively good agreement with each other and similar to published values. This novel approach can now be used for other less well-characterised CYPs.


Assuntos
Citocromo P-450 CYP2B6/metabolismo , Citocromo P-450 CYP3A/metabolismo , Hepatócitos/citologia , Hepatócitos/metabolismo , Proteólise , Interferência de RNA , RNA Interferente Pequeno/genética , Células Cultivadas , Citocromo P-450 CYP2B6/genética , Citocromo P-450 CYP3A/genética , Humanos , Cinética , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , RNA Interferente Pequeno/metabolismo
18.
Nat Commun ; 9(1): 2351, 2018 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-29907739

RESUMO

Checkpoint blockade immunotherapy enhances systemic antitumor immune response by targeting T cell inhibitory pathways; however, inadequate T cell infiltration has limited its anticancer efficacy. Radiotherapy (RT) has local immunomodulatory effects that can alter the microenvironment of irradiated tumors to synergize with immune checkpoint blockade. However, even with high doses of radiation, RT has rarely elicited systemic immune responses. Herein, we report the design of two porous Hf-based nanoscale metal-organic frameworks (nMOFs) as highly effective radioenhancers that significantly outperform HfO2, a clinically investigated radioenhancer in vitro and in vivo. Importantly, the combination of nMOF-mediated low-dose RT with an anti-programmed death-ligand 1 antibody effectively extends the local therapeutic effects of RT to distant tumors via abscopal effects. Our work establishes the feasibility of combining nMOF-mediated RT with immune checkpoint blockade to elicit systemic antitumor immunity in non-T cell-inflamed tumor phenotypes without normal tissue toxicity, promising to broaden the application of checkpoint blockade immunotherapy.

19.
Methods Cell Biol ; 143: 261-279, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29310782

RESUMO

Versican is a chondroitin sulfate proteoglycan found in the extracellular matrix that is important for changes in cell phenotype associated with development and disease. Versican has been shown to be involved in cardiovascular disorders, as well as lung disease and fibrosis, inflammatory bowel disease, cancer, and several other diseases that have an inflammatory component. Versican was first identified as a fibroblast proteoglycan and forms large multimolecular complexes with hyaluronan and other components of the provisional matrix during wound healing and inflammation. The biology of versican has been well studied. Versican plays a major role in embryogenesis, particularly heart formation, where versican deletion proves lethal. The ability to purify versican to characterize and to use in experimental systems is vital to defining its role in development and disease. Protein expression systems have proven challenging to obtain milligram quantities of full-length versican. Here, we describe proteoglycan biochemical purification techniques that have been developed by others, but which we have adapted to use with our source tissues and cells. We also include methods for immunohistochemical localization and quantitation of versican in tissue sections.


Assuntos
Matriz Extracelular/metabolismo , Imagem Molecular/métodos , Versicanas/análise , Animais , Western Blotting/instrumentação , Western Blotting/métodos , Técnicas de Cultura de Células/instrumentação , Técnicas de Cultura de Células/métodos , Cromatografia em Gel/instrumentação , Cromatografia em Gel/métodos , Desenvolvimento Embrionário/fisiologia , Matriz Extracelular/química , Fibroblastos , Coração/embriologia , Humanos , Processamento de Imagem Assistida por Computador , Imuno-Histoquímica , Imagem Molecular/instrumentação , Fixação de Tecidos/instrumentação , Fixação de Tecidos/métodos , Versicanas/química , Versicanas/isolamento & purificação
20.
Nat Biomed Eng ; 2(8): 600-610, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-31015630

RESUMO

Checkpoint blockade immunotherapy relies on energized cytotoxic T cells attacking tumour tissue systemically. However, for many cancers, the reliance on T cell infiltration leads to low response rates. Conversely, radiotherapy has served as a powerful therapy for local tumours over the past 100 years, yet is rarely sufficient to cause systemic tumour rejection. Here, we describe a treatment strategy that combines nanoscale metal-organic framework (nMOF)-enabled radiotherapy-radiodynamic therapy with checkpoint blockade immunotherapy for both local and systemic tumour elimination. In mouse models of breast and colorectal cancer, intratumorally injected nMOFs treated with low doses of X-ray irradiation led to the eradication of local tumours and, when loaded with an inhibitor of the immune checkpoint molecule indoleamine 2,3-dioxygenase, the irradiated nMOFs led to consistent abscopal responses that rejected distal tumours. By combining the advantages of local radiotherapy and systemic tumour rejection via synergistic X-ray-induced in situ vaccination and indoleamine 2,3-dioxygenase inhibition, nMOFs may overcome some of the limitations of checkpoint blockade in cancer treatment.


Assuntos
Imunoterapia/métodos , Estruturas Metalorgânicas/química , Nanoestruturas/química , Terapia por Raios X/métodos , Animais , Antineoplásicos , Morte Celular/efeitos dos fármacos , Morte Celular/efeitos da radiação , Linhagem Celular Tumoral , Terapia Combinada , Humanos , Estruturas Metalorgânicas/farmacologia , Camundongos , Nanomedicina
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