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1.
Mol Carcinog ; 62(9): 1428-1443, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37401875

RESUMO

Therapy using anti-PD-1 immune checkpoint inhibitors (ICI) has revolutionized the treatment of many cancers including head and neck squamous cell carcinomas (HNSCC), but only a fraction of patients respond. To better understand the molecular mechanisms driving resistance, we performed extensive analysis of plasma and tumor tissues before and after a 4-week neoadjuvant trial in which HNSCC patients were treated with the anti-PD-1 inhibitor, nivolumab. Luminex cytokine analysis of patient plasma demonstrated that HPVpos nonresponders displayed high levels of the proinflammatory chemokine, interleukin-8 (IL-8), which decreased after ICI treatment, but remained higher than responders. miRNAseq analysis of tetraspanin-enriched small extracellular vesicles (sEV) purified from plasma of HPVpos nonresponders demonstrated significantly lower levels of seven miRNAs that target IL-8 including miR-146a. Levels of the pro-survival oncoprotein Dsg2, which has been to down-regulate miR-146a, are elevated with HPVpos tumors displaying higher levels than HPVneg tumors. Dsg2 levels decrease significantly following ICI in responders but not in nonresponders. In cultured HPVpos cells, restoration of miR-146a by forced expression or treatment with miR-146a-loaded sEV, reduced IL-8 level, blocked cell cycle progression, and promoted cell death. These findings identify Dsg2, miR-146a, and IL-8 as potential biomarkers for ICI response and suggest that the Dsg2/miR-146a/IL-8 signaling axis negatively impacts ICI treatment outcomes and could be targeted to improve ICI responsiveness in HPVpos HNSCC patients.


Assuntos
Vesículas Extracelulares , Neoplasias de Cabeça e Pescoço , MicroRNAs , Infecções por Papillomavirus , Humanos , Carcinoma de Células Escamosas de Cabeça e Pescoço/tratamento farmacológico , Carcinoma de Células Escamosas de Cabeça e Pescoço/genética , Interleucina-8/genética , Nivolumabe/farmacologia , Nivolumabe/uso terapêutico , Terapia Neoadjuvante , MicroRNAs/genética , MicroRNAs/metabolismo , Neoplasias de Cabeça e Pescoço/tratamento farmacológico , Neoplasias de Cabeça e Pescoço/genética , Vesículas Extracelulares/metabolismo
2.
FASEB J ; 31(8): 3412-3424, 2017 08.
Artigo em Inglês | MEDLINE | ID: mdl-28438789

RESUMO

Extracellular vesicles (EVs) are nanoscale membrane-derived vesicles that serve as intercellular messengers carrying lipids, proteins, and genetic material. Substantial evidence has shown that cancer-derived EVs, secreted by tumor cells into the blood and other bodily fluids, play a critical role in modulating the tumor microenvironment and affecting the pathogenesis of cancer. Here we demonstrate for the first time that squamous cell carcinoma (SCC) EVs were enriched with the C-terminal fragment of desmoglein 2 (Dsg2), a desmosomal cadherin often overexpressed in malignancies. Overexpression of Dsg2 increased EV release and mitogenic content including epidermal growth factor receptor and c-Src. Inhibiting ectodomain shedding of Dsg2 with the matrix metalloproteinase inhibitor GM6001 resulted in accumulation of full-length Dsg2 in EVs and reduced EV release. When cocultured with Dsg2/green fluorescence protein-expressing SCC cells, green fluorescence protein signal was detected by fluorescence-activated cell sorting analysis in the CD90+ fibroblasts. Furthermore, SCC EVs activated Erk1/2 and Akt signaling and enhanced fibroblast cell proliferation. In vivo, Dsg2 was highly up-regulated in the head and neck SCCs, and EVs isolated from sera of patients with SCC were enriched in Dsg2 C-terminal fragment and epidermal growth factor receptor. This study defines a mechanism by which Dsg2 expression in cancer cells can modulate the tumor microenvironment, a step critical for tumor progression.-Overmiller, A. M., Pierluissi, J. A., Wermuth, P. J., Sauma, S., Martinez-Outschoorn, U., Tuluc, M., Luginbuhl, A., Curry, J., Harshyne, L. A., Wahl, J. K. III, South, A. P., Mahoney, M. G. Desmoglein 2 modulates extracellular vesicle release from squamous cell carcinoma keratinocytes.


Assuntos
Carcinoma de Células Escamosas/metabolismo , Desmogleína 2/metabolismo , Vesículas Extracelulares/metabolismo , Regulação Neoplásica da Expressão Gênica/fisiologia , Queratinócitos/metabolismo , Células Cultivadas , Desmogleína 2/genética , Humanos , Queratinócitos/patologia
3.
J Biol Chem ; 291(48): 24857-24865, 2016 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-27703000

RESUMO

Desmosomes are prominent adhesive junctions present between many epithelial cells as well as cardiomyocytes. The mechanisms controlling desmosome assembly and remodeling in epithelial and cardiac tissue are poorly understood. We recently identified protein palmitoylation as a mechanism regulating desmosome dynamics. In this study, we have focused on the palmitoylation of the desmosomal cadherin desmoglein-2 (Dsg2) and characterized the role that palmitoylation of Dsg2 plays in its localization and stability in cultured cells. We identified two cysteine residues in the juxtamembrane (intracellular anchor) domain of Dsg2 that, when mutated, eliminate its palmitoylation. These cysteine residues are conserved in all four desmoglein family members. Although mutant Dsg2 localizes to endogenous desmosomes, there is a significant delay in its incorporation into junctions, and the mutant is also present in a cytoplasmic pool. Triton X-100 solubility assays demonstrate that mutant Dsg2 is more soluble than wild-type protein. Interestingly, trafficking of the mutant Dsg2 to the cell surface was delayed, and a pool of the non-palmitoylated Dsg2 co-localized with lysosomal markers. Taken together, these data suggest that palmitoylation of Dsg2 regulates protein transport to the plasma membrane. Modulation of the palmitoylation status of desmosomal cadherins can affect desmosome dynamics.


Assuntos
Membrana Celular/metabolismo , Desmogleína 2/metabolismo , Desmossomos/metabolismo , Lipoilação/fisiologia , Substituição de Aminoácidos , Linhagem Celular Tumoral , Membrana Celular/genética , Desmogleína 2/genética , Desmossomos/genética , Humanos , Mutação de Sentido Incorreto , Transporte Proteico/fisiologia
4.
Exp Dermatol ; 26(12): 1274-1277, 2017 12.
Artigo em Inglês | MEDLINE | ID: mdl-29105150

RESUMO

The potentially severe side effects of systemic corticosteroids and immunosuppressants used in Pemphigus vulgaris (PV) call for novel therapeutic approaches. In this context, pharmacological inhibition of major pathogenic signalling effectors represents a promising alternative. However, we have also shown that overinhibition of effectors required for epidermal homeostasis can exacerbate PV pathophysiology implicating transepidermal keratinocyte fragility. A feedforward target validation therefore preferentially includes studies on knockout mouse models. We previously reported on successful amelioration of PV blisters following inhibition of non-apoptotic, low-level caspase-3. Here, we use conditional, keratinocyte-specific caspase-3-deficient mice (casp3EKO ) to demonstrate (i) absence of keratinocyte fragility upon injection of the potent Dsg3-specific antibody AK23 and (ii) amelioration of blistering on the background of known signalling effectors. Our results provide the experimental proof of concept justifying translation of the caspase-3 inhibitor approach into PV clinical trials.


Assuntos
Inibidores de Caspase/uso terapêutico , Pênfigo/tratamento farmacológico , Animais , Caspase 3 , Inibidores de Caspase/farmacologia , Avaliação Pré-Clínica de Medicamentos , Estudos de Viabilidade , Camundongos
5.
J Cell Sci ; 127(Pt 17): 3782-93, 2014 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-25002405

RESUMO

Desmosomes are prominent adhesive junctions found in various epithelial tissues. The cytoplasmic domains of desmosomal cadherins interact with a host of desmosomal plaque proteins, including plakophilins, plakoglobin and desmoplakin, which, in turn, recruit the intermediate filament cytoskeleton to sites of cell-cell contact. Although the individual components of the desmosome are known, mechanisms regulating the assembly of this junction are poorly understood. Protein palmitoylation is a posttranslational lipid modification that plays an important role in protein trafficking and function. Here, we demonstrate that multiple desmosomal components are palmitoylated in vivo. Pharmacologic inhibition of palmitoylation disrupts desmosome assembly at cell-cell borders. We mapped the site of plakophilin palmitoylation to a conserved cysteine residue present in the armadillo repeat domain. Mutation of this single cysteine residue prevents palmitoylation, disrupts plakophilin incorporation into the desmosomal plaque and prevents plakophilin-dependent desmosome assembly. Finally, plakophilin mutants unable to become palmitoylated act in a dominant-negative manner to disrupt proper localization of endogenous desmosome components and decrease desmosomal adhesion. Taken together, these data demonstrate that palmitoylation of desmosomal components is important for desmosome assembly and adhesion.


Assuntos
Movimento Celular/fisiologia , Desmossomos/metabolismo , Lipoilação/fisiologia , Placofilinas/metabolismo , Linhagem Celular Tumoral , Desmoplaquinas/metabolismo , Humanos , gama Catenina/metabolismo
6.
J Invest Dermatol ; 144(2): 225-233, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37877931

RESUMO

The recent discovery of extracellular vesicles (EVs) carrying cargo consisting of various bioactive macromolecules that can modulate the phenotype of recipient target cells has revealed an important new mechanism through which cells can signal their neighbors and regulate their microenvironment. Because EV cargo and composition correlate with the physiologic state of their cell of origin, investigations into the role of EVs in disease pathogenesis and progression have become an area of intense study. The physiologic and pathologic effects of EVs on their microenvironment are incredibly diverse and include the modulation of molecular pathways involved in angiogenesis, inflammation, wound healing, epithelial-mesenchymal transition, proliferation, and immune escape. This review examines recent studies on the role of EVs in diseases of the skin and on how differences in EV composition and cargo can alter cell states and the surrounding microenvironment. We also discuss the potential clinical applications of EVs in skin disease diagnosis and management. We examine their value as an easily isolated source of biomarkers to predict disease prognosis or to monitor patient response to treatment. Given the ability of EVs to modulate disease-specific signaling pathways, we also assess their potential to serve as novel personalized precision therapeutic tools for dermatological diseases.


Assuntos
Vesículas Extracelulares , Pele , Humanos , Vesículas Extracelulares/metabolismo , Biomarcadores/metabolismo , Cicatrização , Prognóstico
7.
Front Oncol ; 14: 1412212, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38957320

RESUMO

Introduction: Oral cavity squamous cell carcinoma (OSCC) occurs most frequently in patients >60 years old with a history of tobacco and alcohol use. Epidemiological studies describe increased incidence of OSCC in younger adults (<45 years). Despite its poor prognosis, knowledge of OSCC tumor microenvironment (TME) characteristics in younger adults is scarce and could help inform possible resistance to emerging treatment options. Methods: Patients with OSCC were evaluated using TCGA-HNSC (n=121) and a stage and subsite-matched institutional cohort (n=8) to identify differential gene expression focusing on the extracellular matrix (ECM) and epithelial-mesenchymal transition (EMT) processes in younger (≤45 years) vs. older adults (≥60 years). NanoString nCounter analysis was performed using isolated total RNA from formalin-fixed paraffin-embedded (FFPE) tumor samples. Stained tumor slides from young and old OSCC patients were evaluated for CD8+ T-cell counts using immunohistochemistry. Results: Younger OSCC patients demonstrated significantly increased expression of ECM remodeling and EMT process genes, as well as TME immunosuppression. Gene set enrichment analyses demonstrated increased ECM pathways and concurrent decreased immune pathways in young relative to old patients. Transcripts per million of genetic markers involved in ECM remodeling including LAMB3, VCAN, S100A9, COL5A1, and ITGB2 were significantly increased in tumors of younger vs. older patients (adjusted p-value < 0.10). Young patient TMEs demonstrated a 2.5-fold reduction in CD8+ T-cells as compared to older patients (p < 0.05). Conclusion: Differential gene expression impacting ECM remodeling and TME immunosuppression may contribute to disease progression in younger adult OSCC and has implications on response to evolving treatment modalities, such as immune checkpoint inhibitor therapy.

8.
J Extracell Vesicles ; 13(2): e12404, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38326288

RESUMO

Extracellular vesicles (EVs), through their complex cargo, can reflect the state of their cell of origin and change the functions and phenotypes of other cells. These features indicate strong biomarker and therapeutic potential and have generated broad interest, as evidenced by the steady year-on-year increase in the numbers of scientific publications about EVs. Important advances have been made in EV metrology and in understanding and applying EV biology. However, hurdles remain to realising the potential of EVs in domains ranging from basic biology to clinical applications due to challenges in EV nomenclature, separation from non-vesicular extracellular particles, characterisation and functional studies. To address the challenges and opportunities in this rapidly evolving field, the International Society for Extracellular Vesicles (ISEV) updates its 'Minimal Information for Studies of Extracellular Vesicles', which was first published in 2014 and then in 2018 as MISEV2014 and MISEV2018, respectively. The goal of the current document, MISEV2023, is to provide researchers with an updated snapshot of available approaches and their advantages and limitations for production, separation and characterisation of EVs from multiple sources, including cell culture, body fluids and solid tissues. In addition to presenting the latest state of the art in basic principles of EV research, this document also covers advanced techniques and approaches that are currently expanding the boundaries of the field. MISEV2023 also includes new sections on EV release and uptake and a brief discussion of in vivo approaches to study EVs. Compiling feedback from ISEV expert task forces and more than 1000 researchers, this document conveys the current state of EV research to facilitate robust scientific discoveries and move the field forward even more rapidly.


Assuntos
Exossomos , Vesículas Extracelulares , Vesículas Extracelulares/metabolismo , Exossomos/metabolismo , Transporte Biológico , Biomarcadores/metabolismo , Fenótipo
9.
Dermatol Surg ; 39(6): 934-43, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23458347

RESUMO

BACKGROUND: Disturbance of p53 expression may play an important role in the pathogenesis of ultraviolet (UV) light-induced skin cancer as well as photoaging. OBJECTIVES: To objectively evaluate the potential effect of nonablative facial rejuvenation on p53 expression. PARTICIPANTS AND METHODS: Thirty patients with Fitzpatrick skin type III to IV were divided into five groups. Each group underwent a different nonablative modality: radiofrequency (RF), intense pulsed light (IPL), electro-optical synergy (ELOS) (combined RF and IPL), 1,320-nm neodymium-doped yttrium aluminum garnet (Nd:YAG) laser, and 2,940-nm erbium-doped (Er):YAG laser minipeel. Skin biopsies were obtained before treatment, by the end of treatment, and 3 months after treatment. Biopsies were also taken from 30 controls. Quantitative evaluation of p53 was performed using computer image analysis for immunostained tissues. RESULTS: P53 expression was statistically significantly greater at the end of IPL (p = .02) and ELOS (p = .02) treatments than before treatment but was statistically insignificantly lower (p > .05) 3 months after treatment than at the end of treatment. No significant differences (p > .05) were observed in p53 level after RF, 1,320-nm Nd:YAG, and 2,940-nm Er:YAG mini-peel treatments from baseline. CONCLUSIONS: The increase in epidermal p53 expression after IPL treatment could increase the risk of skin neoplasia by intense pulsed light-induced DNA damage which may lead to dysregulation of apoptosis and initiation of skin cancer.


Assuntos
Técnicas Cosméticas/efeitos adversos , Terapia a Laser/efeitos adversos , Rejuvenescimento/fisiologia , Neoplasias Cutâneas/etiologia , Proteína Supressora de Tumor p53/biossíntese , Adolescente , Adulto , Criança , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem
10.
J Immunother Cancer ; 11(8)2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37536941

RESUMO

BACKGROUND: The combination of nivolumab and ipilimumab has been approved for the treatment of multiple solid tumors. This was a phase I study investigating definitive radioimmunotherapy (RIT) with nivolumab and ipilimumab for the treatment of locally advanced (LA) squamous cell carcinoma of the head and neck (SCCHN). METHODS: Patients with newly diagnosed, stage IVA-IVB SCCHN eligible for cisplatin-based chemotherapy received nivolumab (3 mg/kg every 2 weeks for a total of 17 doses) and ipilimumab (1 mg/kg every 6 weeks for a total of 6 doses) starting 2 weeks prior to radiotherapy. The primary endpoint was safety of definitive RIT. Secondary endpoints included progression-free survival (PFS) and overall survival (OS). Exploratory endpoints included the association of baseline programmed death-ligand 1 (PD-L1) expression as well as on-treatment changes in immune bias with treatment outcomes. RESULTS: Twenty-four patients were enrolled. With a median follow-up of 36.1 months, grade 3 or higher treatment-related adverse events were reported in 21 individuals (88%); 5 individuals developed in-field soft tissue ulceration during consolidation immunotherapy, resulting in one fatality. The 3-year PFS and OS rates were 74% (95% CI 58% to 94%) and 96% (95% CI 88% to 100%), respectively. PD-L1 combined positive score (CPS) did not correlate with death or disease progression. Decreases in extracellular vesicle PD-L1 within the concurrent RIT phase were associated with prolonged PFS (p=0.006). Also, interval decreases in circulating interleukin (IL)4, IL9, IL12, and IL17a during concurrent RIT were associated with subsequent ulceration. CONCLUSIONS: Definitive RIT with nivolumab and ipilimumab has sufficient clinical activity to support further development. Early changes in circulating biomarkers appear able to predict treatment outcomes as well as ensuing in-field soft tissue ulceration. TRIAL REGISTRATION NUMBER: NCT03162731.


Assuntos
Neoplasias de Cabeça e Pescoço , Nivolumabe , Humanos , Nivolumabe/farmacologia , Nivolumabe/uso terapêutico , Ipilimumab/farmacologia , Ipilimumab/uso terapêutico , Antígeno B7-H1 , Carcinoma de Células Escamosas de Cabeça e Pescoço/tratamento farmacológico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias de Cabeça e Pescoço/tratamento farmacológico
11.
iScience ; 26(12): 108568, 2023 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-38162019

RESUMO

Stem cells (SCs) are critical to maintain tissue homeostasis. However, it is currently not known whether signaling through cell junctions protects quiescent epithelial SC reservoirs from depletion during disease-inflicted damage. Using the autoimmune model disease pemphigus vulgaris (PV), this study reveals an unprecedented role for a desmosomal cadherin in governing SC quiescence and regeneration through adhesion signaling in the multipotent mouse hair follicle compartment known as the bulge. Autoantibody-mediated, mechanical uncoupling of desmoglein (Dsg) 3 transadhesion activates quiescent bulge SC which lose their multipotency and stemness, become actively cycling, and finally delaminate from their epithelial niche. This then initiates a self-organized regenerative program which restores Dsg3 function and bulge morphology including SC quiescence and multipotency. These profound changes are triggered by the sole loss of functional Dsg3, resemble major signaling events in Dsg3-/- mice, and are driven by SC-relevant EGFR activation and Wnt modulation requiring longitudinal repression of Hedgehog signaling.

12.
Front Oncol ; 13: 1327478, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38188287

RESUMO

Desmoglein-2 (DSG2) is a calcium-binding single pass transmembrane glycoprotein and a member of the large cadherin family. Until recently, DSG2 was thought to only function as a cell adhesion protein embedded within desmosome junctions designed to enable cells to better tolerate mechanical stress. However, additional roles for DSG2 outside of desmosomes are continuing to emerge, particularly in cancer. Herein, we review the current literature on DSG2 in cancer and detail its impact on biological functions such as cell adhesion, proliferation, migration, invasion, intracellular signaling, extracellular vesicle release and vasculogenic mimicry. An increased understanding of the diverse repertoire of the biological functions of DSG2 holds promise to exploit this cell surface protein as a potential prognostic biomarker and/or target for better patient outcomes. This review explores the canonical and non-canonical functions of DSG2, as well as the context-dependent impacts of DSG2 in the realm of cancer.

13.
Exp Dermatol ; 21(8): 586-91, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22639968

RESUMO

Mutations in the ATP2C1 gene encoding Ca(2+) /Mn(2+) ATPase SPCA1 cause Hailey-Hailey disease (HHD, OMIM 16960). HHD is characterized by epidermal acantholysis. We attempted to model HHD using normal keratinocytes, in which the SPCA1 mRNA was down-regulated with the small inhibitory RNA (siRNA) method. SiRNA inhibition significantly down-regulated the SPCA1 mRNA, as demonstrated by qPCR, and decreased the SPCA1 protein beyond detectable level, as shown by Western analysis. The expression of selected desmosomal, adherens and tight junction (TJ) proteins was then studied in the SPCA1-deficient and control keratinocytes cultured in low (0.06 mm) or high (1.2 mm) calcium concentration. The mRNA and protein levels of most TJ components were up-regulated in non-treated control keratinocyte cultures upon switch from low to high calcium concentration. In contrast, SPCA1-deficient keratinocytes displayed high levels of TJ proteins claudins 1 and 4 even in low calcium. ZO-1 did not, however, follow similar expression patterns. Protein levels of occludin, beta-catenin, E-cadherin, desmoplakin, desmogleins 1-3, desmocollin 2/desmocollin 3 and plakoglobin did not show marked changes in SPCA1-deficient keratinocytes. Indirect immunofluorescence labelling revealed delayed translocation of desmoplakin and desmoglein 3 in desmosomes and increased intracellular pools of TJ and desmosomal components in SPCA1-inhibited keratinocytes. The results show that SPCA1 regulates the levels of claudins 1 and 4, but does not affect desmosomal protein levels, indicating that TJ proteins are differently regulated. The results also suggest a potential role for claudins in HHD.


Assuntos
ATPases Transportadoras de Cálcio/metabolismo , Claudinas/metabolismo , Queratinócitos/metabolismo , Proteínas de Membrana/metabolismo , Pênfigo Familiar Benigno/metabolismo , Junções Íntimas/metabolismo , Cálcio/farmacologia , ATPases Transportadoras de Cálcio/genética , Células Cultivadas , Claudina-1 , Claudina-4 , Desmogleína 3/metabolismo , Desmoplaquinas/metabolismo , Relação Dose-Resposta a Droga , Regulação para Baixo/efeitos dos fármacos , Humanos , Técnicas In Vitro , Queratinócitos/citologia , Queratinócitos/efeitos dos fármacos , Pênfigo Familiar Benigno/fisiopatologia , RNA Mensageiro/metabolismo , RNA Interferente Pequeno/farmacologia
14.
J Exp Clin Cancer Res ; 41(1): 41, 2022 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-35086548

RESUMO

BACKGROUND: Cancer cells have an imbalance in oxidation-reduction (redox) homeostasis. Understanding the precise mechanisms and the impact of the altered redox microenvironment on the immunologic reaction to tumors is limited. METHODS: We isolated exosomes from ovarian cancer cells through ultracentrifuge and characterized by Western-blots and Nanoparticle Tracking Analysis. 2D, 3D-coculture tumor model, and 3D live cell imaging were used to study the interactions between tumor cells, macrophages and CD3 T cells in vitro. The role of exosomal miR-155-5p in tumor growth was evaluated in xenograft nude mice models and immune-competent mice models. Flow cytometry and flow sorting were used to determine the expression levels of miR-155-5p and PD-L1 in ascites and splenic macrophages, and the percentages of CD3 T cells subpopulations. RESULTS: The elevation of reactive oxygen species (ROS) greatly downregulated exosomal miR-155-5p expression in tumor cells. Neutralization of ROS with N-acetyl-L-cysteine (NAC) increased the levels of miR-155-5p in tumor exosomes that were taken up by macrophages, leading to reduction of macrophage migration and tumor spheroid infiltration. We further found that programmed death ligand 1 (PD-L1) is a functional target of miR-155-5p. Co-culture of macrophages pre-treated with NAC-derived tumor exosomes or exosomal miR-155-5p with T-lymphocytes leading to an increased percentage of CD8+ T-lymphocyte and a decreased CD3+ T cell apoptosis through PD-L1 downregulation. Tumor growth in nude mice was delayed by treatment with NAC-derived tumor exosomes. Delivery of tumor exo-miR-155-5p in immune-intact mice suppressed ovarian cancer progression and macrophage infiltration, and activated CD8+ T cell function. It is of note that exo-miR-155-5p inhibited tumor growth more potently than the PD-L1 antibody, suggesting that in addition to PD-L1, other pathways may also be targeted by this approach. CONCLUSIONS: Our findings demonstrate a novel mechanism, ROS-induced down-regulation of miR-155-5p, by which tumors modulate the microenvironment that favors tumor growth. Understanding of the negative impact of ROS on the tumor immune response will improve current therapeutic strategies. Targeting miR-155-5p can be an alternative approach to prevent formation of an immunosuppressive TME through downregulation of PD-L1 and other immunosuppressive factors.


Assuntos
Antígeno B7-H1/metabolismo , Exossomos/imunologia , Imunidade/imunologia , Macrófagos/metabolismo , MicroRNAs/metabolismo , Animais , Linhagem Celular Tumoral , Feminino , Humanos , Camundongos , Camundongos Nus , Espécies Reativas de Oxigênio
15.
Cell Death Dis ; 13(10): 911, 2022 10 29.
Artigo em Inglês | MEDLINE | ID: mdl-36309486

RESUMO

Type 1 diabetes is a complex disease characterized by the lack of endogenous insulin secreted from the pancreatic ß-cells. Although ß-cell targeted autoimmune processes and ß-cell dysfunction are known to occur in type 1 diabetes, a complete understanding of the cell-to-cell interactions that support pancreatic function is still lacking. To characterize the pancreatic endocrine compartment, we studied pancreata from healthy adult donors and investigated a single cell surface adhesion molecule, desmoglein-2 (DSG2). Genetically-modified mice lacking Dsg2 were examined for islet cell mass, insulin production, responses to glucose, susceptibility to a streptozotocin-induced mouse model of hyperglycaemia, and ability to cure diabetes in a syngeneic transplantation model. Herein, we have identified DSG2 as a previously unrecognized adhesion molecule that supports ß-cells. Furthermore, we reveal that DSG2 is within the top 10 percent of all genes expressed by human pancreatic islets and is expressed by the insulin-producing ß-cells but not the somatostatin-producing δ-cells. In a Dsg2 loss-of-function mice (Dsg2lo/lo), we observed a significant reduction in the number of pancreatic islets and islet size, and consequently, there was less total insulin content per islet cluster. Dsg2lo/lo mice also exhibited a reduction in blood vessel barrier integrity, an increased incidence of streptozotocin-induced diabetes, and islets isolated from Dsg2lo/lo mice were more susceptible to cytokine-induced ß-cell apoptosis. Following transplantation into diabetic mice, islets isolated from Dsg2lo/lo mice were less effective than their wildtype counterparts at curing diabetes. In vitro assays using the Beta-TC-6 murine ß-cell line suggest that DSG2 supports the actin cytoskeleton as well as the release of cytokines and chemokines. Taken together, our study suggests that DSG2 is an under-appreciated regulator of ß-cell function in pancreatic islets and that a better understanding of this adhesion molecule may provide new opportunities to combat type 1 diabetes.


Assuntos
Diabetes Mellitus Experimental , Diabetes Mellitus Tipo 1 , Ilhotas Pancreáticas , Animais , Humanos , Camundongos , Sobrevivência Celular , Desmogleínas/metabolismo , Diabetes Mellitus Experimental/genética , Diabetes Mellitus Experimental/metabolismo , Diabetes Mellitus Tipo 1/metabolismo , Insulina/metabolismo , Ilhotas Pancreáticas/metabolismo , Estreptozocina
16.
Clin Cancer Res ; 28(5): 915-927, 2022 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-34911681

RESUMO

PURPOSE: We hypothesize that the addition of the phosphodiesterase-5 inhibitor tadalafil to the PD-1 inhibitor nivolumab, is safe and will augment immune-mediated antitumor responses in previously untreated squamous cell carcinoma of the head and neck (HNSCC). PATIENTS AND METHODS: We conducted a two-arm multi-institutional neoadjuvant randomized trial in any-stage resectable HNSCC (NCT03238365). Patients were stratified at randomization by human papillomavirus (HPV) status. Patients in both arms received nivolumab 240 mg intravenously on days 1 and 15 followed by surgery on day 28. Those in the combination therapy arm also received tadalafil 10 mg orally once daily for 4 weeks. Imaging, blood, and tumor were obtained pretreatment and posttreatment for correlative analysis. RESULTS: Neoadjuvant therapy was well-tolerated with no grade 3 to 5 adverse events and no surgical delays. Twenty-five of 46 (54%) evaluable patients had a pathologic treatment response of ≥20%, including three (7%) patients with a complete pathologic response. Regardless of HPV status, tumor proliferation rate was a negative predictor of response. A strong pretreatment T-cell signature in the HPV-negative cohort was a predictor of response. Tadalafil altered the immune microenvironment, as evidenced by transcriptome data identifying enriched B- and natural killer cell gene sets in the tumor and augmented effector T cells in the periphery. CONCLUSIONS: Preoperative nivolumab ± tadalafil is safe in HNSCC and results in more than 50% of the patients having a pathologic treatment response of at least 20% after 4 weeks of treatment. Pretreatment specimens identified HPV status-dependent signatures that predicted response to immunotherapy while posttreatment specimens showed augmentation of the immune microenvironment with the addition of tadalafil.


Assuntos
Neoplasias de Cabeça e Pescoço , Terapia Neoadjuvante , Carcinoma de Células Escamosas de Cabeça e Pescoço , Neoplasias de Cabeça e Pescoço/tratamento farmacológico , Humanos , Terapia Neoadjuvante/efeitos adversos , Nivolumabe/uso terapêutico , Infecções por Papillomavirus/complicações , Carcinoma de Células Escamosas de Cabeça e Pescoço/tratamento farmacológico , Tadalafila/uso terapêutico , Resultado do Tratamento , Microambiente Tumoral
17.
J Am Acad Dermatol ; 64(3): 524-35, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21315951

RESUMO

BACKGROUND: Multiple therapies involving ablative and nonablative techniques have been developed for rejuvenation of photodamaged skin. Monopolar radiofrequency (RF) is emerging as a gentler, nonablative skin-tightening device that delivers uniform heat to the dermis at a controlled depth. OBJECTIVE: We evaluated the clinical effects and objectively quantified the histologic changes of the nonablative RF device in the treatment of photoaging. METHODS: Six individuals of Fitzpatrick skin type III to IV and Glogau class I to II wrinkles were subjected to 3 months of treatment (6 sessions at 2-week intervals). Standard photographs and skin biopsy specimens were obtained at baseline, and at 3 and 6 months after the start of treatment. We performed quantitative evaluation of total elastin, collagen types I and III, and newly synthesized collagen using computerized histometric and immunohistochemical techniques. Blinded photographs were independently scored for wrinkle improvement. RESULTS: RF produced noticeable clinical results, with high satisfaction and corresponding facial skin improvement. Compared with the baseline, there was a statistically significant increase in the mean of collagen types I and III, and newly synthesized collagen, while the mean of total elastin was significantly decreased, at the end of treatment and 3 months posttreatment. LIMITATIONS: A limitation of this study is the small number of patients, yet the results show a significant improvement. CONCLUSIONS: Although the results may not be as impressive as those obtained by ablative treatments, RF is a promising treatment option for photoaging with fewer side effects and downtime.


Assuntos
Terapia por Radiofrequência , Rejuvenescimento , Envelhecimento da Pele/efeitos da radiação , Colágeno Tipo I/biossíntese , Colágeno Tipo III/biossíntese , Técnicas Cosméticas , Elastina/metabolismo , Face , Feminino , Humanos , Pessoa de Meia-Idade , Pele/metabolismo , Pele/patologia , Resultado do Tratamento
18.
J Cosmet Laser Ther ; 13(3): 98-106, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21609211

RESUMO

The neodymium:yttrium-aluminum-garnet (Nd:YAG) laser is a popular non-ablative treatment used for skin rejuvenation. The purpose of this prospective study was to evaluate the clinical effects, coupled with a quantitative assessment, of the histological changes in response to Nd:YAG 1320-nm laser treatment of periocular wrinkles. Six volunteers with Fitzpatrick skin types III and IV and Glogau class I-II wrinkles were subjected to 3 months of Nd:YAG 1320-nm treatment in the periocular area (six sessions at 2-week intervals). Volunteers were photographed, and skin biopsies were obtained at baseline as well as 3 and 6 months after the start of treatments. Quantitative evaluation of total elastin, newly synthesized tropoelastin, collagen types I, III and VII, and newly synthesized collagen was performed using a computerized morphometric analysis. A noticeable clinical and histological improvement was observed after Nd:YAG 1320-nm treatment. Collagen types I, III and VII, as well as newly synthesized collagen, together with tropoelastin showed a statistically significant increase in response to treatment, while the mean level of total elastin was significantly decreased after treatment. Our data suggest that Nd:YAG 1320 nm is an effective treatment for skin rejuvenation as it stimulates the repair processes, and reverses the clinical, as well as the histopathological, signs of skin aging.


Assuntos
Técnicas Cosméticas , Lasers de Estado Sólido/uso terapêutico , Terapia com Luz de Baixa Intensidade , Rejuvenescimento , Envelhecimento da Pele/efeitos da radiação , Pele/efeitos da radiação , Adulto , Colágeno/análise , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Pele/química , Tropoelastina/análise
19.
J Drugs Dermatol ; 10(11): 1246-52, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22052303

RESUMO

BACKGROUND: The use of intense pulsed light (IPL) for facial rejuvenation had been the topic of many studies. However, few of them discussed quantitative changes in extracellular matrix proteins after IPL therapy. OBJECTIVE: To objectively quantify the histological changes in extracellular matrix proteins after IPL treatment for facial wrinkles. METHODS: Biopsy specimens were obtained from the periocular area of six volunteers of Fitzpatrick skin type III-IV and Glogau's class I-III wrinkles. They were subjected to three months of IPL treatment (six sessions at two-week intervals). Using histological and immunostaining analysis coupled with computerized morphometric analysis, quantitative evaluation of collagen types I, III and VII, newly synthesized collagen, total elastin and tropoelastin was performed for skin biopsies at baseline, end of treatment, and three months post-treatment. RESULTS: Clinical assessment of volunteers did not show clinically noticeable improvement in facial wrinkles after IPL treatment. Furthermore, quantitative evaluation of extracellular matrix proteins showed no statistically significant changes (P>0.05) in response to IPL treatment CONCLUSION: Although 50 percent of volunteers showed mild improvement in skin texture at the end of IPL treatment, none of them reported improvement in skin tightening or wrinkles. No statistically significant histological changes were observed three months post IPL treatment.


Assuntos
Técnicas Cosméticas , Fototerapia/métodos , Rejuvenescimento , Envelhecimento da Pele , Adulto , Biópsia , Colágeno Tipo I/metabolismo , Colágeno Tipo III/metabolismo , Colágeno Tipo VII/metabolismo , Matriz Extracelular/metabolismo , Face , Feminino , Seguimentos , Humanos , Pessoa de Meia-Idade , Resultado do Tratamento
20.
JID Innov ; 1(4): 100053, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34909749

RESUMO

Exosomes or small extracellular vesicles (sEVs) are membrane-bound nanoparticles that carry various macromolecules and act as autocrine and paracrine signaling messengers. In this study, sEVs from epidermoid carcinoma cells influenced by membrane presentation of the glycoprotein desmoglein 2 and its palmitoylation state were investigated. In this study, sEVs were isolated by sequential ultracentrifugation followed by iodixanol density gradient separation. They were then subjected to multiplex profiling of cytokines associated with the surface of intact sEVs. The results revealed a previously undescribed active sorting of cytokines onto the surface of low-density and high-density sEV subpopulations. Specifically, an altered surface presentation of desmoglein 2 decreased FGF-2 and VEGF in low-density sEVs. In addition, in response to desmoglein 2, IL-8 and RANTES were increased in low-density sEVs but only slightly decreased in high-density sEVs. Finally, IL-6 and G-CSF were increased dramatically in high-density sEVs. This comprehensive analysis of the cytokine production profile by squamous cell carcinoma‒derived sEVs highlights their contribution to immune evasion, pro-oncogenic and proangiogenic activity, and the potential to identify diagnostic disease biomarkers.

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