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1.
Cancer Cell Int ; 24(1): 180, 2024 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-38783299

RESUMO

BACKGROUND: Although rare, uveal melanoma (UM) is a life-threatening malignancy. Understanding its biology is necessary to improve disease outcome. Three-dimensional (3D) in vitro culture methods have emerged as tools that incorporate physical and spatial cues that better mimic tumor biology and in turn deliver more predictive preclinical data. Herein, we comprehensively characterize UM cells under different 3D culture settings as a suitable model to study tumor cell behavior and therapeutic intervention. METHODS: Six UM cell lines were tested in two-dimensional (2D) and 3D-culture conditions. For 3D cultures, we used anchorage-dependent (AD) methods where cells were embedded or seeded on top of basement membrane extracts and anchorage-free (AF) methods where cells were seeded on agarose pre-coated plates, ultra-low attachment plates, and on hanging drops, with or without methylcellulose. Cultures were analyzed for multicellular tumor structures (MCTs) development by phase contrast and confocal imaging, and cell wellbeing was assessed based on viability, membrane integrity, vitality, apoptotic features, and DNA synthesis. Vascular endothelial growth factor (VEGF) production was evaluated under hypoxic conditions for cell function analysis. RESULTS: UM cells cultured following anchorage-free methods developed MCTs shaped as spheres. Regardless of their sizes and degree of compaction, these spheres displayed an outer ring of viable and proliferating cells, and a core with less proliferating and apoptotic cells. In contrast, UM cells maintained under anchorage-dependent conditions established several morphological adaptations. Some remained isolated and rounded, formed multi-size irregular aggregates, or adopted a 2D-like flat appearance. These cells invariably conserved their metabolic activity and conserved melanocytic markers (i.e., expression of Melan A/Mart-1 and HMB45). Notably, under hypoxia, cells maintained under 3D conditions secrete more VEGF compared to cells cultured under 2D conditions. CONCLUSIONS: Under an anchorage-free environment, UM cells form sphere-like MCTs that acquire attributes reminiscent of abnormal vascularized solid tumors. UM cells behavior in anchorage-dependent manner exposed diverse cells populations in response to cues from an enriched extracellular matrix proteins (ECM) environment, highlighting the plasticity of UM cells. This study provides a 3D cell culture platform that is more predictive of the biology of UM. The integration of such platforms to explore mechanisms of ECM-mediated tumor resistance, metastatic abilities, and to test novel therapeutics (i.e., anti-angiogenics and immunomodulators) would benefit UM care.

2.
FASEB J ; 37(2): e22732, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36694994

RESUMO

E-cigarettes currently divide public opinion, with some considering them a useful tool for smoking cessation and while others are concerned with potentially adverse health consequences. However, it may take decades to fully understand the effects of e-cigarette use in humans given their relative newness on the market. This highlights the need for comprehensive preclinical studies investigating the effects of e-cigarette exposure on health outcomes. Here, we investigated the impact of chronic, low-level JUUL aerosol exposure on multiple lung outcomes. JUUL is a brand of e-cigarettes popular with youth and young adults. To replicate human exposures, 8- to 12-week-old male and female C57BL/6J mice were exposed to commercially available JUUL products (containing 59 mg/ml nicotine). Mice were exposed to room air, PG/VG, or JUUL daily for 4 weeks. After the exposure period, inflammatory markers were assessed via qRT-PCR, multiplex cytokine assays, and differential cell count. Proteomic and transcriptomic analyses were also performed on samples isolated from the lavage of the lungs; this included unbiased analysis of proteins contained within extracellular vesicles (EVs). Mice exposed to JUUL aerosols for 4 weeks had significantly increased neutrophil and lymphocyte populations in the BAL and some changes in cytokine mRNA expression. However, BAL cytokines did not change. Proteomic and transcriptomic analysis revealed significant changes in numerous biological pathways including neutrophil degranulation, PPAR signaling, and xenobiotic metabolism. Thus, e-cigarettes are not inert and can cause significant cellular and molecular changes in the lungs.


Assuntos
Sistemas Eletrônicos de Liberação de Nicotina , Adulto Jovem , Adolescente , Masculino , Humanos , Feminino , Animais , Camundongos , Transcriptoma , Proteômica , Camundongos Endogâmicos C57BL , Aerossóis/análise , Pulmão
3.
Semin Cancer Biol ; 71: 65-85, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-32450140

RESUMO

Uveal melanoma (UM) is a type of intraocular tumor with a propensity to disseminate to the liver. Despite the identification of the early driver mutations during the development of the pathology, the process of UM metastasis is still not fully comprehended. A better understanding of the genetic, molecular, and environmental factors participating to its spread and metastatic outgrowth could provide additional approaches for UM treatment. In this review, we will discuss the advances made towards the understanding of the pathogenesis of metastatic UM, summarize the current and prospective treatments, and introduce some of the ongoing research in this field.


Assuntos
Neoplasias Hepáticas/secundário , Melanoma/patologia , Neoplasias Uveais/patologia , Animais , Humanos , Fatores de Risco
4.
Exp Eye Res ; 217: 108978, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35134392

RESUMO

Age-related macular degeneration (AMD) is a major cause of blindness in elderly. It is characterized by the loss of central vision due to damaged retinal pigment epithelial (RPE) cells and photoreceptors. Blue Light (BL) exposure was proposed as a risk factor for AMD progression. We undertook this study to determine the effects of BL on the behaviour of RPE cells and their potential mitigation by BL-filtering intraocular lenses (IOL). Human RPE cells were exposed or not to BL, with the absence or presence of either a clear ultraviolet (UV)-filtering IOL (CIOL), or a yellow UV- and BL-filtering IOL (YIOL). Cells were analyzed for their oxidative stress by measuring the levels of reactive oxygen species (ROS), and their viability. BL exposure significantly increased the levels of both total cellular and mitochondrial ROS. While this increase was not affected by placing the CIOL in the BL beam, YIOL decreased the levels of both ROS reservoirs. Increased ROS production was accompanied by increased cell death which was similarly decreased when cells were protected with the YIOL. Pre-treatment of cells with N-acetylcycteine (NAC) abolished the increased cell death, suggesting that the effects of BL on cell viability were mainly due to increased levels of ROS. BL is deleterious to RPE cells due to increased oxidative stress and cell death. These effects were mitigated by filtering these radiations. The use of BL-filtering devices may represent a strategy to reduce these effects on RPE cells and delay the onset of AMD.


Assuntos
Degeneração Macular , Epitélio Pigmentado da Retina , Idoso , Células Epiteliais/metabolismo , Humanos , Luz , Degeneração Macular/metabolismo , Degeneração Macular/prevenção & controle , Estresse Oxidativo , Espécies Reativas de Oxigênio/metabolismo , Epitélio Pigmentado da Retina/metabolismo , Pigmentos da Retina/metabolismo
5.
Cancer Cell Int ; 21(1): 607, 2021 Nov 17.
Artigo em Inglês | MEDLINE | ID: mdl-34789240

RESUMO

BACKGROUND: Uveal melanoma (UM), the most prevalent intraocular tumor in adults, is a highly metastatic and drug resistant lesion. Recent studies have demonstrated cytotoxic and anti-metastatic effects of the antiprogestin and antiglucocorticoid mifepristone (MF) in vitro and in clinical trials involving meningioma, colon, breast, and ovarian cancers. Drug repurposing is a cost-effective approach to bring approved drugs with good safety profiles to the clinic. This current study assessed the cytotoxic effects of MF in human UM cell lines of different genetic backgrounds. METHODS: The effects of incremental concentrations of MF (0, 5, 10, 20, or 40 µM) on a panel of human UM primary (MEL270, 92.1, MP41, and MP46) and metastatic (OMM2.5) cells were evaluated. Cells were incubated with MF for up to 72 h before subsequent assays were conducted. Cellular functionality and viability were assessed by Cell Counting Kit-8, trypan blue exclusion assay, and quantitative label-free IncuCyte live-cell analysis. Cell death was analyzed by binding of Annexin V-FITC and/or PI, caspase-3/7 activity, and DNA fragmentation. Additionally, the release of cell-free DNA was assessed by droplet digital PCR, while the expression of progesterone and glucocorticoid receptors was determined by quantitative real-time reverse transcriptase PCR. RESULTS: MF treatment reduced cellular proliferation and viability of all UM cell lines studied in a concentration-dependent manner. A reduction in cell growth was observed at lower concentrations of MF, with evidence of cell death at higher concentrations. A significant increase in Annexin V-FITC and PI double positive cells, caspase-3/7 activity, DNA fragmentation, and cell-free DNA release suggests potent cytotoxicity of MF. None of the tested human UM cells expressed the classical progesterone receptor in the absence or presence of MF treatment, suggesting a mechanism independent of the modulation of the cognate nuclear progesterone receptor. In turn, all cells expressed non-classical progesterone receptors and the glucocorticoid receptor. CONCLUSION: This study demonstrates that MF impedes the proliferation of UM cells in a concentration-dependent manner. We report that MF treatment at lower concentrations results in cell growth arrest, while increasing the concentration leads to lethality. MF, which has a good safety profile, could be a reliable adjuvant of a repurposing therapy against UM.

6.
Langmuir ; 37(28): 8544-8556, 2021 07 20.
Artigo em Inglês | MEDLINE | ID: mdl-34232664

RESUMO

Liposomes encapsulate different substances ranging from drugs to genes. Control over the average size and size distribution of these nanoparticles is vital for biomedical applications since these characteristics determine to a high degree where liposomes will accumulate in the human body. Micromixers enable the continuous flow synthesis of liposomes, improving size control and reproducibility. Recently, Dean flow dynamics-based micromixers, such as the periodic disturbance mixer (PDM), have been shown to produce controlled-size liposomes in a scalable and reproducible way. However, contrary to micromixers based on molecular diffusion or chaotic advection, their production factors and their influence over liposome properties have not yet been addressed thoroughly. In this work, we present a comprehensive parametric study of the effects of flow conditions and molecular changing factors such as concentration, lipid type, and temperature on the physicochemical characteristics of liposomes. Numerical models and confocal images are used to quantitatively and qualitatively evaluate mixing performance under different liposome production conditions and their relationship with vesicle properties. The total flow rate (TFR) and, to a lesser extent, the flow rate ratio (FRR) control the liposome size and size distribution. Effects on liposome size are also observed by changing the molecular factors. Moreover, the liposome ζ potential is independent of the factors studied here. The micromixer presented in this work enables the production of liposomes as small as 24 nm, with monodispersed to low or close to low polydispersed liposome populations as well as a production rate as high as 41 mg/h.


Assuntos
Lipossomos , Nanopartículas , Humanos , Lipídeos , Tamanho da Partícula , Reprodutibilidade dos Testes
7.
Int J Gynecol Cancer ; 29(2): 346-352, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30659026

RESUMO

OBJECTIVE: Mutations in TP53 are found in the majority of high grade serous ovarian cancers, leading to gain of function or loss of function of its protein product, p53, involved in oncogenesis. There have been conflicting reports as to the impact of the type of these on prognosis. We aim to further elucidate this relationship in our cohort of patients. METHODS: 229 patients with high grade serous ovarian cancer underwent tumor profiling through an institutional molecular screening program with targeted next generation sequencing. TP53 mutations were classified using methods previously described in the literature. Immunohistochemistry on formalin-fixed paraffin embedded tissue was used to assess for TP53 mutation. Using divisive hierarchal clustering, we generated patient clusters with similar clinicopathologic characteristics to investigate differences in outcomes. RESULTS: Six different classification schemes of TP53 mutations were studied. These did not show an association with first platinum-free interval or overall survival. Next generation sequencing reliably predicted mutation in 80% of cases, similar to the proportion detected by immunohistochemistry. Divisive hierarchical clustering generated four main clusters, with cluster 3 having a significantly worse prognosis (p<0.0001; log-rank test). This cluster had a higher concentration of gain of function mutations and these patients were less likely to have undergone optimal debulking surgery. CONCLUSIONS: Different classifications of TP53 mutations did not show an impact on outcomes in this study. Immunohistochemistry was a good predictor for TP53 mutation. Cluster analysis showed that a subgroup of patients with gain of function mutations (cluster 3) had a worse prognosis.

8.
Ophthalmic Plast Reconstr Surg ; 33(3S Suppl 1): S101-S104, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-26882058

RESUMO

A 56-year-old Asian woman presented with an upper eyelid mass. The lesion was exposed after eversion of the eyelid revealing a thickened tarsus with yellowish areas. Working diagnosis was sebaceous carcinoma. Biopsy was performed. Histopathological studies showed a mycotic eumycetoma with Splendore-Hoeppli phenomena and - microbiologic cultures grew Scedosporium apiospermum. The patient was started on voriconazole 200 mg po bid with adequate serum levels. A complete response was observed after 18 weeks of voriconazole therapy. To the best of our knowledge, this is the first published case of S. apiospermum eumycotic mycetoma of the eyelid. It is important to consider mycotic infection in the differential diagnosis of eyelid tumors even in healthy patients.


Assuntos
Adenocarcinoma Sebáceo/diagnóstico , Infecções Oculares Fúngicas/diagnóstico , Doenças Palpebrais/diagnóstico , Neoplasias Palpebrais/diagnóstico , Micetoma/diagnóstico , Scedosporium/isolamento & purificação , Neoplasias das Glândulas Sebáceas/diagnóstico , Antifúngicos/uso terapêutico , Biópsia , Diagnóstico Diferencial , Infecções Oculares Fúngicas/tratamento farmacológico , Infecções Oculares Fúngicas/microbiologia , Doenças Palpebrais/tratamento farmacológico , Doenças Palpebrais/microbiologia , Pálpebras/microbiologia , Pálpebras/patologia , Feminino , Humanos , Pessoa de Meia-Idade , Micetoma/tratamento farmacológico , Micetoma/microbiologia , Voriconazol/uso terapêutico
9.
Nat Methods ; 10(10): 1021-7, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23995386

RESUMO

Fluorescence resonance energy transfer (FRET)-based detection of protein interactions is limited by the very narrow range of FRET-permitting distances. We show two different strategies for the rational design of weak helper interactions that co-recruit donor and acceptor fluorophores for a more robust detection of bimolecular FRET: (i) in silico design of electrostatically driven encounter complexes and (ii) fusion of tunable domain-peptide interaction modules based on WW or SH3 domains. We tested each strategy for optimization of FRET between (m)Citrine and mCherry, which do not natively interact. Both approaches yielded comparable and large increases in FRET efficiencies with little or no background. Helper-interaction modules can be fused to any pair of fluorescent proteins and could, we found, enhance FRET between mTFP1 and mCherry as well as between mTurquoise2 and mCitrine. We applied enhanced helper-interaction FRET (hiFRET) probes to study the binding between full-length H-Ras and Raf1 as well as the drug-induced interaction between Raf1 and B-Raf.


Assuntos
Proteínas de Bactérias/química , Transferência Ressonante de Energia de Fluorescência/métodos , Corantes Fluorescentes/química , Proteínas Luminescentes/química , Mapeamento de Interação de Proteínas/métodos , Células HeLa , Humanos , Modelos Químicos , Modelos Moleculares , Ligação Proteica , Domínios e Motivos de Interação entre Proteínas , Eletricidade Estática , Quinases raf/metabolismo , Proteínas ras/metabolismo , Proteína Vermelha Fluorescente
10.
Ophthalmic Res ; 56(2): 79-84, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-27160208

RESUMO

BACKGROUND: Diabetic retinopathy (DR) is the leading cause of blindness among the working-age population. The earliest morphological manifestation of the disease is pericyte loss, as shown by animal models. AIMS: The purpose of this study was to evaluate the presence of pericytes in vitreous samples (VS) from diabetic and nondiabetic patients. METHODS: VS from 125 patients with and without diabetes were analyzed. Thirty-three of the VS contained blood vessels and were therefore included in further analysis. Pericyte status was evaluated using α-smooth muscle actin and quantified using the following scoring system: total loss (3), >50% loss (2), <50% loss (1), and no loss (0). RESULTS: Of the 33 VS, 29 samples were from patients with diabetes and 4 from nondiabetic patients. Six diabetic cases had a score of 1, 8 diabetic cases had a score of 2, and 15 cases had a score of 3. A positive correlation between glycemia levels and pericyte loss was observed (p = 0.0016; Spearman's r = 0.61). Moreover, all nondiabetic cases had a score of 0 (sensitivity and specificity = 100%). CONCLUSION: Pericyte loss in VS might be a sensitive and specific marker of DR that correlates with glycemia levels. Furthermore, VS, which are currently discarded, may contain valuable information for diabetic management.


Assuntos
Retinopatia Diabética/cirurgia , Diagnóstico Precoce , Pericitos/patologia , Vitrectomia/métodos , Corpo Vítreo/patologia , Adulto , Idoso , Retinopatia Diabética/patologia , Retinopatia Diabética/fisiopatologia , Progressão da Doença , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico , Estudos Retrospectivos , Fatores de Tempo , Adulto Jovem
11.
J Proteome Res ; 13(1): 300-13, 2014 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-24313378

RESUMO

Relating protein concentration to cell-type-specific responses is one of the remaining challenges for obtaining a quantitative systems level understanding of mammalian signaling. Here we used mass-spectrometry (MS)- and antibody-based quantitative proteomic approaches to measure protein abundances for 75% of a hand-curated reconstructed ErbB network of 198 proteins, in two established cell types (HEK293 and MCF-7) and in primary keratinocyte cells. Comparison with other quantitative studies allowed building a set of ErbB network proteins expressed in all cells and another which are cell-specific and could impart specific properties to the network. As a proof-of-concept of the importance of protein concentration, we generated a small simplified mathematical model encompassing ligand binding, followed by receptor dimerization, activation, and degradation. The model predicts ErbB phosphorylation in HEK293, MCF-7, and keratinocyte cells simply by incorporating cell-type-specific ErbB1, ErbB2, and caveolin-1 abundances but otherwise contains similar rate constants. Altogether, the data provide a resource for protein abundances and localization to be included in larger mathematical models, enabling the generation of cell-type-specific computational models. MS data have been deposited to the ProteomeXchange via PRIDE (with identifier PXD000623) and PASSEL (with identifier PASS00372).


Assuntos
Receptor ErbB-2/metabolismo , Transdução de Sinais , Linhagem Celular , Humanos
12.
Cell Death Dis ; 15(9): 668, 2024 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-39266560

RESUMO

Extracellular vesicles (EVs) have emerged as key players in intercellular communication, facilitating the transfer of crucial cargo between cells. Liquid biopsy, particularly through the isolation of EVs, has unveiled a rich source of potential biomarkers for health and disease, encompassing proteins and nucleic acids. A milestone in this exploration occurred a decade ago with the identification of extracellular vesicle-associated DNA (EV-DNA) in the bloodstream of a patient diagnosed with pancreatic cancer. Subsequent years have witnessed substantial advancements, deepening our insights into the molecular intricacies of EV-DNA emission, detection, and analysis. Understanding the complexities surrounding the release of EV-DNA and addressing the challenges inherent in EV-DNA research are pivotal steps toward enhancing liquid biopsy-based strategies. These strategies, crucial for the detection and monitoring of various pathological conditions, particularly cancer, rely on a comprehensive understanding of why and how EV-DNA is released. In our review, we aim to provide a thorough summary of a decade's worth of research on EV-DNA. We will delve into diverse mechanisms of EV-DNA emission, its potential as a biomarker, its functional capabilities, discordant findings in the field, and the hurdles hindering its clinical application. Looking ahead to the next decade, we envision that advancements in EV isolation and detection techniques, coupled with improved standardization and data sharing, will catalyze the development of novel strategies exploiting EV-DNA as both a source of biomarkers and therapeutic targets.


Assuntos
DNA , Vesículas Extracelulares , Humanos , Vesículas Extracelulares/metabolismo , DNA/metabolismo , DNA/sangue , DNA/genética , Biomarcadores Tumorais/sangue , Biomarcadores Tumorais/metabolismo , Biomarcadores Tumorais/genética , Biópsia Líquida/métodos
13.
JAMA Netw Open ; 7(9): e2431722, 2024 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-39235812

RESUMO

Importance: Metastatic breast cancer (MBC) poses a substantial clinical challenge despite advancements in diagnosis and treatment. While tissue biopsies offer a static snapshot of disease, liquid biopsy-through detection of circulating tumor DNA (ctDNA)-provides minimally invasive, real-time insight into tumor biology. Objective: To determine the association between ctDNA and survival outcomes in patients with MBC. Data Sources: An electronic search was performed in 5 databases (CINAHL, Cochrane Library, Embase, Medline, and Web of Science) and included all articles published from inception until October 23, 2023. Study Selection: To be included in the meta-analysis, studies had to (1) include women diagnosed with MBC; (2) report baseline plasma ctDNA data; and (3) report overall survival, progression-free survival, or disease-free survival with associated hazards ratios. Data Extraction and Synthesis: Titles and abstracts were screened independently by 2 authors. Data were pooled using a random-effects model. This study adhered to the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) reporting guideline, and quality was assessed using the Newcastle-Ottawa Scale. Main Outcomes and Measures: The primary study outcome was the association between detection of specific genomic alterations in ctDNA with survival outcomes. Secondary objectives were associations of study methodology with survival. Results: Of 3162 articles reviewed, 37 met the inclusion criteria and reported data from 4264 female patients aged 20 to 94 years. Aggregated analysis revealed a significant association between ctDNA detection and worse survival (hazard ratio, 1.40; 95% CI, 1.22-1.58). Subgroup analysis identified significant associations of TP53 and ESR1 alterations with worse survival (hazard ratios, 1.58 [95% CI, 1.34-1.81] and 1.28 [95% CI, 0.96-1.60], respectively), while PIK3CA alterations were not associated with survival outcomes. Stratifying by detection method, ctDNA detection through next-generation sequencing and digital polymerase chain reaction was associated with worse survival (hazard ratios, 1.48 [95% CI, 1.22-1.74] and 1.28 [95% CI, 1.05-1.50], respectively). Conclusions and Relevance: In this systematic review and meta-analysis, detection of specific genomic alterations in ctDNA was associated with worse overall, progression-free, and disease-free survival, suggesting its potential as a prognostic biomarker in MBC. These results may help guide the design of future studies to determine the actionability of ctDNA findings.


Assuntos
Neoplasias da Mama , DNA Tumoral Circulante , Humanos , DNA Tumoral Circulante/sangue , DNA Tumoral Circulante/genética , Neoplasias da Mama/sangue , Neoplasias da Mama/mortalidade , Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Feminino , Metástase Neoplásica , Biomarcadores Tumorais/sangue , Biomarcadores Tumorais/genética , Pessoa de Meia-Idade
14.
Arq Bras Oftalmol ; 88(1): e20230037, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39109736

RESUMO

PURPOSE: To characterize the extracellular vesicle protein cargo in the aqueous humor and plasma of patients with ocular toxoplasmosis. METHODS: Aqueous humor and plasma were collected from six patients with active ocular toxoplasmosis and six patients with cataract. Extracellular vesicles were isolated, and western blotting and mass spectrometry were performed for protein analysis. RESULTS: All plasma samples from patients with ocular toxoplasmosis and cataract were positive for the tetraspanins CD63 and TSG101. However, the aqueous humor from patients with ocular toxoplasmosis was positive only for CD63. Sixty-seven new unreported proteins were identified in the aqueous humor and plasma of patients with the ocular toxoplasmosis and cataract. Of the 67 proteins, 10 and 7 were found only in the cataract and ocular toxoplasmosis groups, respectively. In general, these proteins were involved in immune system activation and retina homeostasis and were related to infections and retina-associated diseases. CONCLUSION: The distinct protein signatures between ocular toxoplasmosis and cataract may be helpful in the differential diagnosis of ocular toxoplasmosis. However, more studies are needed to better understand the role of these proteins in the pathogenesis of ocular toxoplasmosis.


Assuntos
Humor Aquoso , Western Blotting , Catarata , Vesículas Extracelulares , Toxoplasmose Ocular , Humanos , Humor Aquoso/metabolismo , Humor Aquoso/química , Humor Aquoso/parasitologia , Vesículas Extracelulares/metabolismo , Masculino , Feminino , Catarata/metabolismo , Pessoa de Meia-Idade , Adulto , Tetraspanina 30/análise , Tetraspanina 30/metabolismo , Espectrometria de Massas , Idoso , Proteínas de Ligação a DNA , Fatores de Transcrição , Complexos Endossomais de Distribuição Requeridos para Transporte
15.
Melanoma Res ; 34(4): 285-295, 2024 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-38847739

RESUMO

Uveal melanoma is the most common intraocular tumor in adults. Our group has previously developed a human uveal melanoma animal model; however, adverse effects caused by the immunosuppressive agent, cyclosporine A, prevented animals from surviving more than 12 weeks. In this study, we tested multiple cyclosporine A doses over an extended disease course up to 20 weeks, providing complete clinical imaging of intraocular tumors, histopathological analysis and liquid biopsy biomarker analysis. Twenty albino rabbits were divided into four groups with different daily cyclosporine A schedules (0-10 mg/kg) and inoculated with human uveal melanoma cell lines, 92.1 or MP41, into the suprachoroidal space. Rabbits were monitored with fundoscopy, ultrasound and optical coherence tomography. Intraocular tumors (macroscopic or microscopic) were detected in all study animals. Tumor size and growth were correlated to cyclosporine A dose, with tumors regressing when cyclosporine A was arrested. All tumors expressed HMB-45 and MelanA; however, tumor size, pigmentation and cell morphology differed in 92.1 vs. MP41 tumors. Finally, across all groups, circulating tumor DNA from plasma and aqueous humor was detected earlier than tumor detection by imaging and correlated to tumor growth. In conclusion, using three clinically relevant imaging modalities (fundoscopy, ultrasonography and optical coherence tomography) and liquid biopsy, we were successfully able to monitor tumor progression in our rabbit xenograft model of human uveal melanoma.


Assuntos
Melanoma , Neoplasias Uveais , Animais , Neoplasias Uveais/patologia , Coelhos , Melanoma/patologia , Humanos , Biópsia Líquida/métodos , Modelos Animais de Doenças , Ensaios Antitumorais Modelo de Xenoenxerto , Linhagem Celular Tumoral
16.
Cancer Med ; 12(15): 15777-15787, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37526056

RESUMO

BACKGROUND: There is an alarming increase in human papillomavirus-associated head and neck cancer (HNC), reaching epidemic levels. While patient prognosis is generally good, off-target treatment effects are associated with decreased quality of life. Thus, non-invasive strategies to predict treatment response and risk of recurrence could help de-escalate treatment. In this study, we tested circulating tumor (ct)DNA in liquid biopsies (blood/saliva) of HPV-positive HNC patients to assess treatment response and disease progression. METHODS: A total of 235 blood and saliva samples were collected from 60 HPV-positive and 17 HPV-negative HNC patients (control group) before and/or after treatment. Samples were analyzed using ddPCR for HPV16/18/31/33/35/45 and correlated with imaging and pathological examination. RESULTS: HPV-ctDNA detection was significantly higher prior to treatment (91%) than after treatment (8.0%) (χ2 p < 0.00001), with high concordance between saliva and blood (93%). In matched samples, all patients positive for ctDNA before treatment showed significant reductions in ctDNA levels post treatment (p < 0.0001). All but one patient with persistent ctDNA after treatment showed residual tumor and subsequent recurrence. Finally, fragmentomic analysis revealed shifts in cell-free DNA fragment size after treatment, suggesting a complementary biomarker for treatment response. CONCLUSIONS: Blood and saliva were found to be good sources of HPV-ctDNA. The presence of ctDNA strongly correlated with treatment response, demonstrating clinical utility as a non-invasive biomarker to monitor tumor progression in HPV-positive HNC. Liquid biopsy based ctDNA testing could be an effective approach to predict recurrence and stratify patients for de-escalation of treatment, thereby improving quality of life.


Assuntos
DNA Tumoral Circulante , Neoplasias de Cabeça e Pescoço , Infecções por Papillomavirus , Humanos , Papillomavirus Humano , Infecções por Papillomavirus/complicações , Infecções por Papillomavirus/diagnóstico , Papillomavirus Humano 16/genética , Neoplasia Residual , Saliva , Qualidade de Vida , Papillomavirus Humano 18/genética , Neoplasias de Cabeça e Pescoço/terapia , Neoplasias de Cabeça e Pescoço/complicações , DNA Tumoral Circulante/genética , Biomarcadores Tumorais/genética , Recidiva Local de Neoplasia
17.
J Extracell Vesicles ; 12(8): e12341, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37563798

RESUMO

Lymph nodes (LNs) are frequently the first sites of metastasis. Currently, the only prognostic LN assessment is determining metastatic status. However, there is evidence suggesting that LN metastasis is facilitated by the formation of a pre-metastatic niche induced by tumour derived extracellular vehicles (EVs). Therefore, it is important to detect and modify the LN environmental changes. Earlier work has demonstrated that neutrophil extracellular traps (NETs) can sequester and promote distant metastasis. Here, we first confirmed that LN NETs are associated with reduced patient survival. Next, we demonstrated that NETs deposition precedes LN metastasis and NETs inhibition diminishes LN metastases in animal models. Furthermore, we discovered that EVs are essential to the formation of LN NETs. Finally, we showed that lymphatic endothelial cells secrete CXCL8/2 in response to EVs inducing NETs formation and the promotion of LN metastasis. Our findings reveal the role of EV-induced NETs in LN metastasis and provide potential immunotherapeutic vulnerabilities that may occur early in the metastatic cascade.


Assuntos
Armadilhas Extracelulares , Vesículas Extracelulares , Animais , Metástase Linfática/patologia , Células Endoteliais , Linfonodos/patologia
18.
J Extracell Vesicles ; 11(10): e12270, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-36271888

RESUMO

Extracellular vesicles (EVs) play a key role in cellular communication both in physiological conditions and in pathologies such as cancer. Emerging evidence has shown that EVs are active carriers of molecular cargo (e.g. protein and nucleic acids) and a powerful source of biomarkers and targets. While recent studies on EV-associated DNA (EV-DNA) in human biofluids have generated a large amount of data, there is currently no database that catalogues information on EV-DNA. To fill this gap, we have manually curated a database of EV-DNA data derived from human biofluids (liquid biopsy) and in-vitro studies, called the Extracellular Vesicle-Associated DNA Database (EV-ADD). This database contains validated experimental details and data extracted from peer-reviewed published literature. It can be easily queried to search for EV isolation methods and characterization, EV-DNA isolation techniques, quality validation, DNA fragment size, volume of starting material, gene names and disease context. Currently, our database contains samples representing 23 diseases, with 13 different types of EV isolation techniques applied on eight different human biofluids (e.g. blood, saliva). In addition, EV-ADD encompasses EV-DNA data both representing the whole genome and specifically including oncogenes, such as KRAS, EGFR, BRAF, MYC, and mitochondrial DNA (mtDNA). An EV-ADD data metric system was also integrated to assign a compliancy score to the MISEV guidelines based on experimental parameters reported in each study. While currently available databases document the presence of proteins, lipids, RNA and metabolites in EVs (e.g. Vesiclepedia, ExoCarta, ExoBCD, EVpedia, and EV-TRACK), to the best of our knowledge, EV-ADD is the first of its kind to compile all available EV-DNA datasets derived from human biofluid samples. We believe that this database provides an important reference resource on EV-DNA-based liquid biopsy research, serving as a learning tool and to showcase the latest developments in the EV-DNA field. EV-ADD will be updated yearly as newly published EV-DNA data becomes available and it is freely available at www.evdnadatabase.com.


Assuntos
Vesículas Extracelulares , Ácidos Nucleicos , Humanos , Bases de Dados de Ácidos Nucleicos , Proteínas Proto-Oncogênicas B-raf/metabolismo , Proteínas Proto-Oncogênicas p21(ras)/metabolismo , Biópsia Líquida/métodos , Vesículas Extracelulares/metabolismo , Ácidos Nucleicos/metabolismo , Proteínas/metabolismo , RNA/metabolismo , Receptores ErbB/genética , Biomarcadores/metabolismo , Lipídeos , DNA Mitocondrial/metabolismo
19.
Ocul Oncol Pathol ; 7(1): 1-16, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33796511

RESUMO

In the era of precision oncology, major strides are being made to use individual tumor information for clinical decision-making. Differing from traditional biopsy methods, the emerging practice of liquid biopsy provides a minimally invasive way of obtaining tumor cells and derived molecules. Liquid biopsy provides a means to detect and monitor disease progression, recurrence, and treatment response in a noninvasive way, and to potentially complement classical biopsy. Uveal melanoma (UM) is a unique malignancy, with diagnosis heavily reliant on imaging, few repeat biopsies, and a high rate of metastasis, which occurs hematogenously and often many years after diagnosis. In this disease setting, a noninvasive biomarker to detect, monitor, and study the disease in real time could lead to better disease understanding and patient care. While advances have been made in the detection of tumor-disseminated components, sensitivity and specificity remain important challenges. Ambiguity remains in how to interpret current findings and in how liquid biopsy can have a place in clinical practice. Related publications in UM are few compared to other cancers, but with further studies we may be able to uncover more about the biology of disseminated molecules and the mechanisms involved in the progression to metastasis.

20.
Micromachines (Basel) ; 12(9)2021 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-34577745

RESUMO

The shape and dimensions of a micromixer are key elements in the mixing process. Accurately quantifying the mixing efficiency enables the evaluation of the performance of a micromixer and the selection of the most suitable one for specific applications. In this paper, two methods are investigated to evaluate the mixing efficiency: a numerical model and an experimental model with a software image processing technique. Using two methods to calculate the mixing efficiency, in addition to corroborating the results and increasing their reliability, creates various possible approaches that can be selected depending on the circumstances, resources, amount of data to be processed and processing time. Image processing is an easy-to-implement tool, is applicable to different programming languages, is flexible, and provides a quick response that allows the calculation of the mixing efficiency using a process of filtering of images and quantifying the intensity of the color, which is associated with the percentage of mixing. The results showed high similarity between the two methods, with a difference ranging between 0 and 6% in all the evaluated points.

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