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1.
Drug Deliv Transl Res ; 14(2): 342-359, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37587289

RESUMO

Glioblastoma multiforme (GBM) is regarded as a highly aggressive brain cancer with a poor prognosis. There is an increase in the expression of P-glycoprotein (P-gp), responsible for multidrug resistance (MDR), making it a potential target for improving drug responses. Additionally, glioblastoma stem cells (GSCs) increase resistance to chemo- and radiotherapy and play a major role in cancer relapse. In this study, we targeted P-gp using a small molecule inhibitor, reversan (RV), to inhibit MDR that prolonged the retention of drugs in the cytosolic milieu. To eliminate GBM and GSCs, we have used two well-established anti-cancer drugs, regorafenib (RF) and curcumin (CMN). To improve the pharmacokinetics and decrease systemic delivery of drugs, we developed nanostructure hybrid lipid capsules (nHLCs), where hydrophobic drugs can be loaded in the core, and their physicochemical properties were determined by dynamic light scattering (DLS) and cryo-scanning electron microscopy (SEM). Inhibition of MDR by RV has also shown enhanced retention of nHLC in GBM cells. Co-delivery of drug-loaded nHLCs, pre-treated with RV, exhibited superior cytotoxicity in both GBM and GSCs than their individual doses and effectively reduced the size and stemness of tumor spheres and accelerated the rate of apoptosis, suggesting a promising treatment for glioblastoma.


Assuntos
Neoplasias Encefálicas , Glioblastoma , Humanos , Glioblastoma/tratamento farmacológico , Glioblastoma/metabolismo , Células-Tronco Neoplásicas , Resistência a Múltiplos Medicamentos , Neoplasias Encefálicas/tratamento farmacológico , Neoplasias Encefálicas/metabolismo , Lipídeos , Linhagem Celular Tumoral
2.
Eur J Pharm Biopharm ; 195: 114169, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38159872

RESUMO

Acute and chronic wounds are vulnerable to infection and delayed healing and require critical care and advanced wound protection. To overcome the challenges, dual therapy of antibacterial and growth factors will be a novel wound care strategy. The present study explores airbrushed core-shell nanofiber for dual delivery of epidermal growth factor (EGF) and amoxicillin (AMOX) in a sustained manner. A blend of polycaprolactone (PCL)-polyethylene oxide (PEO) was used to prepare the shell compartment for amoxicillin loading and poly-DL-lactide (PDLLA) core for EGF loading by using a customized airbrush setup. Characterization result shows a uniform distribution of nanofibers ranging between 200 and 500 nm in diameter. Amoxicillin loading in the shell compartment offers an initial burst release followed by a sustained release for up to 14 days. Whereas EGF in the core part shows a continuous sustained release throughout the release study.In-vitrostudy indicates the biocompatibility of EGF-AMOX loaded core-shell nanofibers with human dermal fibroblast cell (HDF) cells and a higher cellular proliferation compared to control samples. Gene expression data show an increase in fold change of collagen I and tropoelastin expression, indicating the regenerative properties of EGF-AMOX encapsulated nanofiber. The combination of bioactive core (EGF) and antibiotic shell (amoxicillin) in an airbrushed nanofibrous scaffold is a novel approach, which is the first time explored to deliver sustainable therapy to treat skin wounds. Our results demonstrate that PCL-PEO-Amoxicillin/PDLLA-EGF-loaded core-shell nanofibers are promising dual therapy scaffolds to deliver effective skin wound care, with the possibility of direct deposition on the wound.


Assuntos
Fator de Crescimento Epidérmico , Nanofibras , Humanos , Preparações de Ação Retardada , Cicatrização , Poliésteres , Antibacterianos/farmacologia , Amoxicilina
3.
ACS Appl Bio Mater ; 6(12): 5399-5413, 2023 Dec 18.
Artigo em Inglês | MEDLINE | ID: mdl-37975516

RESUMO

The glioblastoma stem cell (GSC) population in glioblastoma multiforme (GBM) poses major complication in clinical oncology owing to increased resistance to chemotherapeutic drugs, thereby limiting treatment in patients with recurring glioblastoma. To completely eradicate glioblastoma, a single therapy module is not enough; therefore, there is a need to develop a multimodal approach to eliminate bulk tumors along with the CSC population. With an aim to target transporters associated with multidrug resistance (MDR), such as P-glycoprotein (P-gp), a small-molecule inhibitor, reversan (RV) was used along with multifunctional magnetic nanoparticles (MNPs) for hyperthermia (HT) therapy and targeted drug delivery. Higher efflux of free doxorubicin (Dox) from the cells was stabilized by encapsulation in PPS-MnFe nanoparticles, whose physicochemical properties were determined by dynamic light scattering (DLS) and transmission electron microscopy (TEM). Treatment with RV also enhanced the cellular uptake of PPS-MnFe-Dox, whereas RV and magnetic hyperthermia (MHT) together showed prolonged retention of fluorescence dye, Rhodamine123 (R123), in glioblastoma cells compared with individual treatment. Overall, in this work, we demonstrated the synergistic action of RV and HT to combat MDR in GBM and GSCs, and chemo-hyperthermia therapy enhanced the cytotoxic effect of the chemotherapeutic drug Dox (with lower effective concentration) and induced a higher degree of apoptosis compared to single-drug dosage.


Assuntos
Glioblastoma , Hipertermia Induzida , Humanos , Glioblastoma/tratamento farmacológico , Doxorrubicina/farmacologia , Doxorrubicina/uso terapêutico , Resistência a Múltiplos Medicamentos , Células-Tronco
4.
Front Cell Infect Microbiol ; 13: 1248782, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37727809

RESUMO

Background and aims: Hepatitis B virus (HBV) infection affects 300 million individuals worldwide, representing a major factor for the development of hepatic complications. Although existing antivirals are effective in suppressing replication, eradication of HBV is not achieved. Therefore, a multi-faceted approach involving antivirals and immunomodulatory agents is required. Non-human primates are widely used in pre-clinical studies due to their close evolutionary relationship to humans. Nonetheless, it is fundamental to identify the differences in immune response between humans and these models. Thus, we performed a transcriptomic characterization and interspecies comparison of the early immune responses to HBV in human and cynomolgus macaques. Methods: We characterized early transcriptomic changes in human and cynomolgus B cells, T cells, myeloid and plasmacytoid dendritic cells (pDC) exposed to HBV ex vivo for 2 hours. Differentially-expressed genes were further compared to the profiles of HBV-infected patients using publicly-available single-cell data. Results: HBV induced a wide variety of transcriptional changes in all cell types, with common genes between species representing only a small proportion. In particular, interferon gamma signaling was repressed in human pDCs. At the gene level, interferon gamma inducible protein 16 (IFI16) was upregulated in macaque pDCs, while downregulated in humans. Moreover, IFI16 expression in pDCs from chronic HBV-infected patients anti-paralleled serum HBsAg levels. Conclusion: Our characterization of early transcriptomic changes induced by HBV in humans and cynomolgus macaques represents a useful resource for the identification of shared and divergent host responses, as well as potential immune targets against HBV.


Assuntos
Hepatite B , Transcriptoma , Animais , Humanos , Vírus da Hepatite B/genética , Interferon gama , Antivirais , Macaca fascicularis , Hepatite B/genética
5.
Photodiagnosis Photodyn Ther ; 44: 103747, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37567329

RESUMO

INTRODUCTION: Photodynamic therapy (PDT) has emerged as an effective therapy for various dermatology conditions, including oral lichen planus (OLP). The objective of this study was to evaluate the efficacy of PDT in managing OLP and to compare its effectiveness with corticosteroid therapy (CST). MATERIALS AND METHODS: A comprehensive electronic search was conducted following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines, utilizing databases such as PubMed, Embase, Google Scholar, Semantic Scholar, X-mole, and Dimensions. The inclusion criteria encompassed randomized controlled clinical trials (RCTs) that included patients with OLP undergoing treatment with PDT and CST, with no limitations on sample size or patient age. RESULTS: Out of 197 studies identified, only 8 met the inclusion criteria, involving 210 patients (104 in Group I: PDT, 106 in Group II: CST), with a female to male ratio of 3.75. Three studies reported OLP lesion numbers, six studies described lesion types, and five studies provided lesion location information. The efficacy of both PDT and CST was assessed using lesion size, pain, Thongprasom sign (ThS) scoring, efficacy index (EI), and clinical severity index (CSI). The limited and inconsistent reporting of data hindered to conduct a meta-analysis. CONCLUSIONS: PDT effectively treats OLP lesions, leading to significant symptom reduction and improved functionality. However, limited relevant RCTs and heterogeneous data reporting hinder definitive conclusions regarding the efficacy of PDT compared to CTS.


Assuntos
Líquen Plano Bucal , Fotoquimioterapia , Masculino , Feminino , Humanos , Fotoquimioterapia/métodos , Fármacos Fotossensibilizantes/uso terapêutico , Líquen Plano Bucal/tratamento farmacológico , Ensaios Clínicos Controlados Aleatórios como Assunto , Corticosteroides/uso terapêutico
7.
Biomater Sci ; 11(11): 3938-3951, 2023 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-37093244

RESUMO

With the increasing dependence on fluorescence bioimaging, luminogens with aggregation-induced emission (AIE) properties have gained significant attention due to their excellent photostabilization, minimal photobleaching, high reliability, and superior biocompatibility. Since mitochondria are crucial subcellular organelles in eukaryotic cells with important biological functions, organelle-specific AIE emitters with distinct functions have been highly sought after, but with limited success using simple synthetic methods. Here, we describe a strategy for synthesizing two triphenylamine (TPA) based acrylonitriles, tethered to different donor groups, TPA and phenothiazine (PTZ), respectively, with superior AIE properties using Suzuki coupling. We conducted a systematic and detailed experimental analysis of the structural characteristics of both AIE luminogens, which exhibited excellent photostability, a large Stokes shift, and bright solid-state emission. A cell viability study carried out with F1 and F2 dyes revealed that both luminogens exhibited excellent biocompatibility. Based on fluorescence experiments, F2 displayed excellent AIE characteristics, permeability, biocompatibility, and photostability compared to rhodamine 123, allowing it to selectively stain and track mitochondria in cancer cells over an extended period of time. The Pearson correlation coefficient of F2 and rhodamine 123 was estimated to have an r-value of 0.99. Our findings are expected to provide insight into the synthesis of an extensive archive of AIE-based acrylonitriles with fascinating properties for mitochondrial staining.


Assuntos
Corantes Fluorescentes , Mitocôndrias , Humanos , Rodamina 123 , Reprodutibilidade dos Testes , Corantes Fluorescentes/química , Células HeLa
8.
Cancers (Basel) ; 15(7)2023 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-37046702

RESUMO

Endometrial cancer (EC) is the seventh most common tumor in women, and prognosis of recurrent and metastatic disease is poor. Cervical cancer (CC) represents the fifth most common gynecological cancer. While ECs are more common in developed countries, the incidence of CC has decreased due to the recent implementation of large screening and vaccination programs. Until very recently, patients with advanced or unresectable EC or CC had very limited treatment options and were receiving in first line setting platinum/taxane-based chemotherapy (CT). Significant progress in the treatment of gynecological cancers has occurred in the last few years, with the use of innovative targeted therapies and immunotherapy. However, targeting the immune system in patients with gynecological tumors remains challenging and is not always successful. In ovarian cancer, several immunotherapy treatment regimens have been investigated (as monotherapy and combination therapy in first and subsequent lines of treatment) and showed poor responses. Therefore, we specifically focused our review on EC and CC for their specific immune-related features and therapeutic results demonstrated with immunotherapy. We report recent and current immunotherapy-based clinical trials and provide a review of emerging data that are likely to impact immunotherapy development based on increased biomarkers' identification to monitor response and overcome resistance.

9.
Artif Intell Med ; 137: 102493, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36868692

RESUMO

Recent advances in causal inference techniques, more specifically, in the theory of structural causal models, provide the framework for identifying causal effects from observational data in cases where the causal graph is identifiable, i.e., the data generation mechanism can be recovered from the joint distribution. However, no such studies have been performed to demonstrate this concept with a clinical example. We present a complete framework to estimate the causal effects from observational data by augmenting expert knowledge in the model development phase and with a practical clinical application. Our clinical application entails a timely and essential research question, the effect of oxygen therapy intervention in the intensive care unit (ICU). The result of this project is helpful in a variety of disease conditions, including severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) patients in the ICU. We used data from the MIMIC-III database, a widely used health care database in the machine learning community with 58,976 admissions from an ICU in Boston, MA, to estimate the oxygen therapy effect on morality. We also identified the model's covariate-specific effect on oxygen therapy for more personalized intervention.


Assuntos
COVID-19 , Humanos , SARS-CoV-2 , Unidades de Terapia Intensiva , Oxigênio , Bases de Dados Factuais
10.
Front Neurosci ; 17: 1108212, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36937670

RESUMO

There is increasing evidence that viral infections are the source/origin of various types of encephalitis, encephalomyelitis, and other neurological and cognitive disorders. While the involvement of certain viruses, such as the Nipah virus and measles virus, is known, the mechanisms of neural invasion and the factors that trigger intense immune reactions are not fully understood. Based on recent publications, this review discusses the role of the immune response, interactions between viruses and glial cells, and cytokine mediators in the development of inflammatory diseases in the central nervous system. It also highlights the significant gaps in knowledge regarding these mechanisms.

11.
Acta Biomater ; 161: 1-36, 2023 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-36907233

RESUMO

Immunotherapy involves the therapeutic alteration of the patient's immune system to identify, target, and eliminate cancer cells. Dendritic cells, macrophages, myeloid-derived suppressor cells, and regulatory T cells make up the tumor microenvironment. In cancer, these immune components (in association with some non-immune cell populations like cancer-associated fibroblasts) are directly altered at a cellular level. By dominating immune cells with molecular cross-talk, cancer cells can proliferate unchecked. Current clinical immunotherapy strategies are limited to conventional adoptive cell therapy or immune checkpoint blockade. Targeting and modulating key immune components presents an effective opportunity. Immunostimulatory drugs are a research hotspot, but their poor pharmacokinetics, low tumor accumulation, and non-specific systemic toxicity limit their use. This review describes the cutting-edge research undertaken in the field of nanotechnology and material science to develop biomaterials-based platforms as effective immunotherapeutics. Various biomaterial types (polymer-based, lipid-based, carbon-based, cell-derived, etc.) and functionalization methodologies for modulating tumor-associated immune/non-immune cells are explored. Additionally, emphasis has been laid on discussing how these platforms can be used against cancer stem cells, a fundamental contributor to chemoresistance, tumor relapse/metastasis, and failure of immunotherapy. Overall, this comprehensive review strives to provide up-to-date information to an audience working at the juncture of biomaterials and cancer immunotherapy. STATEMENT OF SIGNIFICANCE: Cancer immunotherapy possesses incredible potential and has successfully transitioned into a clinically lucrative alternative to conventional anti-cancer therapies. With new immunotherapeutics getting rapid clinical approval, fundamental problems associated with the dynamic nature of the immune system (like limited clinical response rates and autoimmunity-related adverse effects) have remained unanswered. In this context, treatment approaches that focus on modulating the compromised immune components within the tumor microenvironment have garnered significant attention amongst the scientific community. This review aims to provide a critical discussion on how various biomaterials (polymer-based, lipid-based, carbon-based, cell-derived, etc.) can be employed along with immunostimulatory agents to design innovative platforms for selective immunotherapy directed against cancer and cancer stem cells.


Assuntos
Materiais Biocompatíveis , Neoplasias , Humanos , Materiais Biocompatíveis/farmacologia , Materiais Biocompatíveis/uso terapêutico , Neoplasias/patologia , Imunoterapia/métodos , Células-Tronco Neoplásicas/patologia , Lipídeos , Microambiente Tumoral
13.
Prog Biomater ; 10(2): 131-150, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34224092

RESUMO

Functional tissue regeneration using synthetic biomaterials requires proliferation and heterotypic differentiation of stem/progenitor cells within a specialized heterogeneous (biophysical-biochemical) microenvironment. The current techniques have limitations to develop synthetic hydrogels, mimicking native extracellular matrix porosity along with heterogeneous microenvironmental cues of matrix mechanics, degradability, microstructure and cell-cell interactions. Here, we have developed a microenvironment modulating system to fabricate in situ porous hydrogel matrix with two or more distinct tailored microenvironmental niches within microbeads and the hydrogel matrix for multicellular tissue regeneration. Electrosprayed pectin-gelatin blended microbeads and crosslinked alginate hydrogel system help to tailor microenvironmental niches of encapsulated cells where two different cells are surrounded by a specific microenvironment. The effect of different microenvironmental parameters associated with the microbead/hydrogel matrix was evaluated using human umbilical-cord mesenchymal stem cells (hUCMSCs). The osteogenic differentiation of hUCMSCs in the hydrogel matrix was evaluated for bone tissue regeneration. This will be the first report on microenvironment modulating microbead-hydrogel system to encapsulate two/more types of cells in a hydrogel, where each cell is surrounded with distinct niches for heterogeneous tissue regeneration.

14.
Elife ; 102021 01 28.
Artigo em Inglês | MEDLINE | ID: mdl-33507150

RESUMO

Antiviral effectors such as natural killer (NK) cells have impaired functions in chronic hepatitis B (CHB) patients. The molecular mechanism responsible for this dysfunction remains poorly characterised. We show that decreased cytokine production capacity of peripheral NK cells from CHB patients was associated with reduced expression of NKp30 and CD16, and defective mTOR pathway activity. Transcriptome analysis of patients NK cells revealed an enrichment for transcripts expressed in exhausted T cells suggesting that NK cell dysfunction and T cell exhaustion employ common mechanisms. In particular, the transcription factor TOX and several of its targets were over-expressed in NK cells of CHB patients. This signature was predicted to be dependent on the calcium-associated transcription factor NFAT. Stimulation of the calcium-dependent pathway recapitulated features of NK cells from CHB patients. Thus, deregulated calcium signalling could be a central event in both T cell exhaustion and NK cell dysfunction occurring during chronic infections.


Assuntos
Fatores de Restrição Antivirais/imunologia , Hepatite B Crônica/imunologia , Células Matadoras Naturais/imunologia , Infecção Persistente/imunologia , Linfócitos T/imunologia , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem
15.
Cell Mol Immunol ; 18(9): 2140-2152, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-32398809

RESUMO

T cell development proceeds under the influence of a network of transcription factors (TFs). The precise role of Zeb1, a member of this network, remains unclear. Here, we report that Zeb1 expression is induced early during T cell development in CD4-CD8- double-negative (DN) stage 2 (DN2). Zeb1 expression was further increased in the CD4+CD8+ double-positive (DP) stage before decreasing in more mature T cell subsets. We performed an exhaustive characterization of T cells in Cellophane mice that bear Zeb1 hypomorphic mutations. The Zeb1 mutation profoundly affected all thymic subsets, especially DN2 and DP cells. Zeb1 promoted the survival and proliferation of both cell populations in a cell-intrinsic manner. In the periphery of Cellophane mice, the number of conventional T cells was near normal, but invariant NKT cells, NK1.1+ γδ T cells and Ly49+ CD8 T cells were virtually absent. This suggested that Zeb1 regulates the development of unconventional T cell types from DP progenitors. A transcriptomic analysis of WT and Cellophane DP cells revealed that Zeb1 regulated the expression of multiple genes involved in the cell cycle and TCR signaling, which possibly occurred in cooperation with Tcf1 and Heb. Indeed, Cellophane DP cells displayed stronger signaling than WT DP cells upon TCR engagement in terms of the calcium response, phosphorylation events, and expression of early genes. Thus, Zeb1 is a key regulator of the cell cycle and TCR signaling during thymic T cell development. We propose that thymocyte selection is perturbed in Zeb1-mutated mice in a way that does not allow the survival of unconventional T cell subsets.


Assuntos
Receptores de Antígenos de Linfócitos T alfa-beta , Subpopulações de Linfócitos T , Animais , Diferenciação Celular , Proliferação de Células , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Receptores de Antígenos de Linfócitos T alfa-beta/genética , Transdução de Sinais/genética , Timo
16.
Methods Mol Biol ; 1938: 3-18, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30617969

RESUMO

Astrocytes are known to provide trophic support to neurons and were originally thought to be passive space-filling cells in the brain. However, recent advances in astrocyte development and functions have highlighted their active roles in controlling brain functions by modulating synaptic transmission. A bidirectional cross talk between astrocytic processes and neuronal synapses define the concept of tripartite synapse. Any change in astrocytic structure/function influences neuronal activity which could lead to neurodevelopmental and neurodegenerative disorders. In this chapter, we briefly overview the methodologies used in deciphering the mechanisms of dynamic interplay between astrocytes and neurons.


Assuntos
Astrócitos/fisiologia , Neurônios/fisiologia , Sinapses/fisiologia , Animais , Encéfalo/citologia , Encéfalo/fisiologia , Encéfalo/ultraestrutura , Técnicas de Cultura de Células , Diferenciação Celular , Técnicas de Cocultura , Técnicas Citológicas , Humanos , Técnicas In Vitro , Células-Tronco Pluripotentes Induzidas/citologia , Células-Tronco Pluripotentes Induzidas/metabolismo , Transmissão Sináptica
17.
J Immunol ; 201(8): 2331-2344, 2018 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-30185518

RESUMO

Effective B cell responses such as cytokine secretion, proliferation, and Ab-specific responses are essential to clear hepatitis B virus (HBV) infection. However, HBV alters numerous immune pathways to persist in the host. B cell activity depends on activation of the innate sensor TLR9 by viral or bacterial DNA motifs. How HBV can deregulate B cell functions remains unknown. In this study, we show that HBV can enter and decrease TLR9 expression in human primary B cells. Using PBMCs from human blood donors, we show that TLR9 expression was reduced in all peripheral B cells subsets exposed to HBV. B cell function mediated by TLR9, but not TLR7, such as proliferation and proinflammatory cytokines secretion, were abrogated in the presence of HBV; however, global Ig secretion was not downregulated. Mechanistically, we show, using human myeloma B cell line RPMI 8226, that the surface Ag hepatitis B surface Ag was responsible for TLR9 dysfunction. hepatitis B surface Ag suppressed the phosphorylation and thus the activation of the transcription factor CREB, preventing TLR9 promoter activity. Finally, we corroborated our in vitro findings in a cohort of chronic HBV carriers and found that TLR9 expression and function were significantly suppressed. The effect of HBV on TLR9 activity in B cells gives insights into oncoviral immune escape strategies, providing knowledge to develop novel immunotherapeutic approaches in chronic HBV-carrier patients.


Assuntos
Linfócitos B/imunologia , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/metabolismo , Antígenos de Superfície da Hepatite B/metabolismo , Vírus da Hepatite B/fisiologia , Hepatite B Crônica/imunologia , Receptor Toll-Like 9/metabolismo , Adulto , Idoso , Linfócitos B/virologia , Linhagem Celular Tumoral , Proliferação de Células , Estudos de Coortes , Citocinas/metabolismo , Regulação para Baixo , Feminino , Antígenos de Superfície da Hepatite B/imunologia , Humanos , Evasão da Resposta Imune , Tolerância Imunológica , Integrases/genética , Integrases/metabolismo , Ativação Linfocitária , Masculino , Pessoa de Meia-Idade , Fosforilação , Regiões Promotoras Genéticas/genética , Adulto Jovem
18.
PLoS Pathog ; 14(8): e1007158, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-30089163

RESUMO

Human papillomavirus type 16 (HPV16) and other oncoviruses have been shown to block innate immune responses and to persist in the host. However, to avoid viral persistence, the immune response attempts to clear the infection. IL-1ß is a powerful cytokine produced when viral motifs are sensed by innate receptors that are members of the inflammasome family. Whether oncoviruses such as HPV16 can activate the inflammasome pathway remains unknown. Here, we show that infection of human keratinocytes with HPV16 induced the secretion of IL-1ß. Yet, upon expression of the viral early genes, IL-1ß transcription was blocked. We went on to show that expression of the viral oncoprotein E6 in human keratinocytes inhibited IRF6 transcription which we revealed regulated IL-1ß promoter activity. Preventing E6 expression using siRNA, or using E6 mutants that prevented degradation of p53, showed that p53 regulated IRF6 transcription. HPV16 abrogation of p53 binding to the IRF6 promoter was shown by ChIP in tissues from patients with cervical cancer. Thus E6 inhibition of IRF6 is an escape strategy used by HPV16 to block the production IL-1ß. Our findings reveal a struggle between oncoviral persistence and host immunity; which is centered on IL-1ß regulation.


Assuntos
Regulação da Expressão Gênica/imunologia , Evasão da Resposta Imune/imunologia , Fatores Reguladores de Interferon/metabolismo , Interleucina-1beta/biossíntese , Infecções por Papillomavirus/imunologia , Papillomavirus Humano 16/imunologia , Humanos , Fatores Reguladores de Interferon/imunologia , Interleucina-1beta/imunologia , Queratinócitos/imunologia , Queratinócitos/metabolismo , Queratinócitos/virologia , Proteínas Oncogênicas Virais/metabolismo , Infecções por Papillomavirus/metabolismo , Proteínas Repressoras/metabolismo
20.
J Virol ; 91(19)2017 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-28724760

RESUMO

Several lines of evidence indicate that cutaneous human papillomavirus (HPV) types belonging to the beta genus of the HPV phylogenetic tree synergize with UV radiation in the development of skin cancer. Accordingly, the E6 and E7 oncoproteins from some beta HPV types are able to deregulate pathways related to immune response and cellular transformation. Toll-like receptor 9 (TLR9), in addition to playing a role in innate immunity, has been shown to be involved in the cellular stress response. Using primary human keratinocytes as experimental models, we have shown that UV irradiation (and other cellular stresses) activates TLR9 expression. This event is closely linked to p53 activation. Silencing the expression of p53 or deleting its encoding gene affected the activation of TLR9 expression after UV irradiation. Using various strategies, we have also shown that the transcription factors p53 and c-Jun are recruited onto a specific region of the TLR9 promoter after UV irradiation. Importantly, the E6 and E7 oncoproteins from beta HPV38, by inducing the accumulation of the p53 antagonist ΔNp73α, prevent the UV-mediated recruitment of these transcription factors onto the TLR9 promoter, with subsequent impairment of TLR9 gene expression. This study provides new insight into the mechanism that mediates TLR9 upregulation in response to cellular stresses. In addition, we show that HPV38 E6 and E7 are able to interfere with this mechanism, providing another explanation for the possible cooperation of beta HPV types with UV radiation in skin carcinogenesis.IMPORTANCE Beta HPV types have been suggested to act as cofactors in UV-induced skin carcinogenesis by altering several cellular mechanisms activated by UV radiation. We show that the expression of TLR9, a sensor of damage-associated molecular patterns produced during cellular stress, is activated by UV radiation in primary human keratinocytes (PHKs). Two transcription factors known to be activated by UV radiation, p53 and c-Jun, play key roles in UV-activated TLR9 expression. The E6 and E7 oncoproteins from beta HPV38 strongly inhibit UV-activated TLR9 expression by preventing the recruitment of p53 and c-Jun to the TLR9 promoter. Our findings provide additional support for the role that beta HPV types play in skin carcinogenesis by preventing activation of specific pathways upon exposure of PHKs to UV radiation.


Assuntos
Transformação Celular Neoplásica/patologia , Ativação Enzimática/efeitos da radiação , Queratinócitos/metabolismo , Papillomaviridae/crescimento & desenvolvimento , Proteínas E7 de Papillomavirus/metabolismo , Receptor Toll-Like 9/metabolismo , Receptor Toll-Like 9/efeitos da radiação , Proteínas Virais/metabolismo , Proliferação de Células/genética , Células Cultivadas , Humanos , Proteínas Quinases JNK Ativadas por Mitógeno/metabolismo , Regiões Promotoras Genéticas/genética , Interferência de RNA , RNA Interferente Pequeno/genética , Pele/parasitologia , Pele/virologia , Neoplasias Cutâneas/virologia , Receptor Toll-Like 9/genética , Proteína Supressora de Tumor p53/genética , Proteína Supressora de Tumor p53/metabolismo , Raios Ultravioleta
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