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1.
Int J Mol Sci ; 25(4)2024 Feb 14.
Article in English | MEDLINE | ID: mdl-38396953

ABSTRACT

Biosynthetic gold nanoparticles (bAuNPs) present a promising avenue for enhancing bio-compatibility and offering an economically and environmentally responsible alternative to traditional production methods, achieved through a reduction in the use of hazardous chemicals. While the potential of bAuNPs as anticancer agents has been explored, there is a limited body of research focusing on the crucial physicochemical conditions influencing bAuNP production. In this study, we aim to identify the optimal growth phase of Pseudomonas aeruginosa cultures that maximizes the redox potential and coordinates the formation of bAuNPs with increased efficiency. The investigation employs 2,6-dichlorophenolindophenol (DCIP) as a redox indicator. Simultaneously, we explore the impact of temperature, pH, and incubation duration on the biosynthesis of bAuNPs, with a specific emphasis on their potential application as antitumor agents. Characterization of the resulting bAuNPs is conducted using ATR-FT-IR, TEM, and UV-Vis spectroscopy. To gain insights into the anticancer potential of bAuNPs, an experimental model is employed, utilizing both non-neoplastic (HPEpiC) and neoplastic (PC3) epithelial cell lines. Notably, P. aeruginosa cultures at 9 h/OD600 = 1, combined with biosynthesis at pH 9.0 for 24 h at 58 °C, produce bAuNPs that exhibit smaller, more spherical, and less aggregated characteristics. Crucially, these nanoparticles demonstrate negligible effects on HPEpiC cells while significantly impacting PC3 cells, resulting in reduced viability, migration, and lower IL-6 levels. This research lays the groundwork for the development of more specialized, economical, and ecologically friendly treatment modalities.


Subject(s)
Antineoplastic Agents , Metal Nanoparticles , Prostatic Neoplasms , Humans , Male , Anti-Bacterial Agents/chemistry , Gold/chemistry , Spectroscopy, Fourier Transform Infrared , Metal Nanoparticles/therapeutic use , Metal Nanoparticles/chemistry , Antineoplastic Agents/pharmacology , Antineoplastic Agents/therapeutic use , Prostatic Neoplasms/drug therapy , Green Chemistry Technology/methods , Plant Extracts/chemistry
2.
J Am Chem Soc ; 142(24): 10869-10880, 2020 06 17.
Article in English | MEDLINE | ID: mdl-32456416

ABSTRACT

The ability to create ways to control drug activation at specific tissues while sparing healthy tissues remains a major challenge. The administration of exogenous target-specific triggers offers the potential for traceless release of active drugs on tumor sites from antibody-drug conjugates (ADCs) and caged prodrugs. We have developed a metal-mediated bond-cleavage reaction that uses platinum complexes [K2PtCl4 or Cisplatin (CisPt)] for drug activation. Key to the success of the reaction is a water-promoted activation process that triggers the reactivity of the platinum complexes. Under these conditions, the decaging of pentynoyl tertiary amides and N-propargyls occurs rapidly in aqueous systems. In cells, the protected analogues of cytotoxic drugs 5-fluorouracil (5-FU) and monomethyl auristatin E (MMAE) are partially activated by nontoxic amounts of platinum salts. Additionally, a noninternalizing ADC built with a pentynoyl traceless linker that features a tertiary amide protected MMAE was also decaged in the presence of platinum salts for extracellular drug release in cancer cells. Finally, CisPt-mediated prodrug activation of a propargyl derivative of 5-FU was shown in a colorectal zebrafish xenograft model that led to significant reductions in tumor size. Overall, our results reveal a new metal-based cleavable reaction that expands the application of platinum complexes beyond those in catalysis and cancer therapy.


Subject(s)
Amides/chemistry , Antineoplastic Agents/pharmacology , Cisplatin/pharmacology , Morphinans/chemistry , Platinum/chemistry , Animals , Antineoplastic Agents/chemistry , Cell Line, Tumor , Cell Proliferation/drug effects , Cisplatin/chemistry , Drug Liberation , Drug Screening Assays, Antitumor , Humans , Molecular Structure , Neoplasms, Experimental/drug therapy , Neoplasms, Experimental/pathology , Zebrafish
3.
Can J Infect Dis Med Microbiol ; 2018: 5295619, 2018.
Article in English | MEDLINE | ID: mdl-30073039

ABSTRACT

Piper is the largest genus of the Piperaceae family. The species of this genus have diverse biological activities and are used in pharmacopeia throughout the world. They are also used in folk medicine for treatment of many diseases in several countries including Brazil, China, India, Jamaica, and Mexico. In Brazil, Piper species are distributed throughout the national territory, making this genus a good candidate for biological activity screening. During our studies with Piper essential oils, we evaluated its activity against Rhizopus oryzae, the main agent of mucormycosis. The main compounds of seven Piper essential oils analyzed were Piper callosum-safrole (53.8%), P. aduncum-dillapiole (76.0%), P. hispidinervum-safrole (91.4%), P. marginatum-propiopiperone (13.2%), P. hispidum-γ-terpinene (30.9%), P. tuberculatum-(E)-caryophyllene (30.1%), and Piper sp.-linalool (14.6%). The minimum inhibitory concentration of Piper essential oils against R. oryzae ranged from 78.12 to >1250 µg/mL. The best result of total inhibition of biofilm formation was obtained with Piper sp. starting from 4.88 µg/mL. Considering the bioactive potential of EOs against planktonic cells and biofilm formation of R. oryzae could be of great interest for development of antimicrobials for therapeutic use in treatment of fungal infection.

4.
Planta Med ; 80(7): 550-6, 2014 May.
Article in English | MEDLINE | ID: mdl-24841967

ABSTRACT

The leaves and bark of Croton cajucara, a shrub from the Amazon region, have been used in folk medicine to treat diabetes, malaria, and gastrointestinal and liver disorders. The essential oil from the leaves, rich in linalool, presented antileishmanial and antimicrobial activities. A chemotype of this species was found with an essential oil rich in 7-hydroxycalamenene. During our studies of the C. cajucara essential oil, we isolated 7-hydroxycalamenene at > 98 % purity. The minimum inhibitory concentration of 7-hydroxycalamenene against Absidia cylindrospora, Cunninghamella elegans, Mucor circinelloides, Mucor circinelloides f. circinelloides, Mucor mucedo, Mucor plumbeus, Mucor ramosissimus, Rhizopus microsporus, Rhizopus oryzae, and Syncephalastrum racemosum ranged from 19.53 to 2500 µg/mL. The reference drug used, amphotericin B, presented a minimum inhibitory concentration ranging from 0.085 µg/mL to 43.87 µg/mL. 7-Hydroxycalamenene also altered spore differentiation and total lipid content. Ultrastructural analysis by transmission electron microscopy showed significant alterations in the cellular structure of R. oryzae.


Subject(s)
Croton/chemistry , Oils, Volatile/pharmacology , Plant Extracts/pharmacology , Plant Oils/pharmacology , Rhizopus/drug effects , Sesquiterpenes/pharmacology , Zygomycosis/drug therapy , Acyclic Monoterpenes , Amphotericin B/pharmacology , Medicine, Traditional , Microbial Sensitivity Tests , Monoterpenes/chemistry , Monoterpenes/isolation & purification , Monoterpenes/pharmacology , Mycelium/drug effects , Oils, Volatile/chemistry , Oils, Volatile/isolation & purification , Plant Bark/chemistry , Plant Extracts/chemistry , Plant Extracts/isolation & purification , Plant Leaves/chemistry , Plant Oils/chemistry , Plant Oils/isolation & purification , Rhizopus/growth & development , Rhizopus/ultrastructure , Sesquiterpenes/chemistry , Sesquiterpenes/isolation & purification
5.
J Enzyme Inhib Med Chem ; 29(1): 12-7, 2014 Feb.
Article in English | MEDLINE | ID: mdl-23323991

ABSTRACT

Abstract Lippia alba (Miller) N.E. Brown is an aromatic plant known locally as "Erva-cidreira-do-campo" that has great importance in Brazilian folk medicine. The aim of our study was to evaluate the antidermatophytic potential of linalool-rich essential oil (EO) from L. alba and analyze the ability of this EO to inhibit peptidase and keratinase activities, which are important virulence factors in dermatophytes. The minimum inhibitory concentrations (MICs) of L. alba EO were 39, 156 and 312 µg/mL against Trichophyton rubrum, Epidermophyton floccosum and Microsporum gypseum, respectively. To evaluate the influence of L. alba EO on the proteolytic and keratinolytic activities of these dermatophytes, specific inhibitory assays were performed. The results indicated that linalool-rich EO from L. alba inhibited the activity of proteases and keratinases secreted from dermatophytes, and this inhibition could be a possible mechanism of action against dermatophytes. Due to the effective antidermatophytic activity of L. alba EO, further experiments should be performed to explore the potential of this linalool-rich EO as an alternative antifungal therapy.


Subject(s)
Arthrodermataceae/enzymology , Lippia/chemistry , Monoterpenes/analysis , Oils, Volatile/pharmacology , Peptide Hydrolases/drug effects , Protease Inhibitors/pharmacology , Acyclic Monoterpenes , Electrophoresis, Polyacrylamide Gel , Hydrogen-Ion Concentration , Microbial Sensitivity Tests , Oils, Volatile/chemistry
6.
Acta Med Port ; 37(3): 163-171, 2024 Feb 05.
Article in Portuguese | MEDLINE | ID: mdl-36939679

ABSTRACT

INTRODUCTION: School-age test anxiety is an important risk factor for school performance. Notwithstanding, few studies seek to identify which strategies are effective in improving test anxiety. The aim of this study was to assess whether a cognitive-behavioural intervention for high school students could significantly reduce test anxiety. MATERIAL AND METHODS: Two-arm, cluster-randomized controlled, unblinded, parallel, trial. Participants were 10th grade students from Alves Martins High School in Viseu, Portugal. Students were randomized at class level to receive a cognitive-behavioural-based intervention combined with mindfulness, psychoeducation, and relaxation techniques, or to a control group with no intervention. Participants' anxiety levels were measured using the Test Anxiety Questionnaire. The analysis of the effect of the intervention was carried out on an intention-to-treat basis at the class level, using multilevel mixed effects models and Bayesian modelling. RESULTS: The intervention had a significant effect in reducing test anxiety (d = 0.81, 95% CI 0.45;1.17, Bayes factor = 31.3). Male gender was an independent risk factor for smaller reductions in anxiety levels. The intervention was more effective in reducing the worry component of test anxiety (d = 0.76, 95% CI 0.41;1.11, Bayes factor = 19.9) than the emotionality component (d = 0.63, 95% CI 0.31;0.95, Bayes factor = 6.6). CONCLUSION: A cognitive-behavioural intervention specifically designed to reduce test anxiety, using a combination of mindfulness, psychoeducation and relaxation techniques, was effective in reducing test anxiety levels. TRIAL REGISTRATION: Retrospectively registered on clinicaltrials.gov (NCT05481099) in 08/01/2022.


Introdução: A ansiedade face aos testes é um importante fator condicionante da performance escolar. Contudo, são escassos os estudos que procuram identificar quais as estratégias eficazes na sua melhoria. Este estudo teve como objetivo testar a eficácia de uma intervenção cognitivo-comportamental na redução da ansiedade face aos testes em alunos do ensino secundário. Material e Métodos: Estudo experimental, aleatorizado por clusters (turmas), controlado, sem ocultação, com dois grupos paralelos, com alunos do 10.º ano da Escola Secundária Alves Martins em Viseu, Portugal. Os alunos foram aleatorizados ao nível da turma para receber uma combinação de técnicas cognitivas e comportamentais, de mindfulness, psicoeducação e técnicas de relaxamento, ou para um grupo controlo sem intervenção. Os níveis de ansiedade dos participantes foram medidos através do Questionário de Ansiedade face aos Testes. A análise do efeito da intervenção foi realizada na base de intenção de tratar ao nível da turma recorrendo a modelos de efeitos mistos multinível e modelação bayesiana. Resultados: A intervenção teve um efeito significativo na redução da ansiedade face aos testes (d = 0,81, IC 95% 0,45;1,17, fator de Bayes = 31,3). Pertencer ao sexo masculino revelou-se um fator de risco independente para uma menor redução nos níveis de ansiedade. O efeito da intervenção foi mais pronunciado na redução da preocupação face aos testes (d = 0,76, IC 95% 0,41;1,11, fator de Bayes = 19,9) quando comparado com a emocionalidade (d = 0,63, IC 95% 0,31;0,95, fator de Bayes = 6,6). Conclusão: Uma intervenção especificamente desenhada para reduzir a ansiedade face aos testes, usando uma combinação de técnicas cognitivas e comportamentais de mindfulness, psicoeducação e técnicas de relaxamento, foi eficaz na redução dos níveis de ansiedade. Registo do Estudo: Estudo registado a posteriori (registo retrospetivo) em ClinicalTrials.gov com o número NCT05481099 em 01/08/2022.


Subject(s)
Cognitive Behavioral Therapy , Test Anxiety , Humans , Male , Bayes Theorem , Students , Cognition
7.
Dis Model Mech ; 17(8)2024 Aug 01.
Article in English | MEDLINE | ID: mdl-39114912

ABSTRACT

The Bacillus Calmette-Guérin (BCG) vaccine is the oldest cancer immunotherapeutic agent in use. Despite its effectiveness, its initial mechanisms of action remain largely unknown. Here, we elucidate the earliest cellular mechanisms involved in BCG-induced tumor clearance. We developed a fast preclinical in vivo assay to visualize in real time and at single-cell resolution the initial interactions among bladder cancer cells, BCG and innate immunity using the zebrafish xenograft model. We show that BCG induced the recruitment and polarization of macrophages towards a pro-inflammatory phenotype, accompanied by induction of the inflammatory cytokines tnfa, il1b and il6 in the tumor microenvironment. Macrophages directly induced apoptosis of human cancer cells through zebrafish TNF signaling. Macrophages were crucial for this response as their depletion completely abrogated the BCG-induced phenotype. Contrary to the general concept that macrophage anti-tumoral activities mostly rely on stimulating an effective adaptive response, we demonstrate that macrophages alone can induce tumor apoptosis and clearance. Thus, our results revealed an additional step to the BCG-induced tumor immunity model, while providing proof-of-concept experiments demonstrating the potential of this unique model to test innate immunomodulators.


Subject(s)
Apoptosis , BCG Vaccine , Macrophages , Signal Transduction , Urinary Bladder Neoplasms , Zebrafish , Urinary Bladder Neoplasms/pathology , Urinary Bladder Neoplasms/drug therapy , Urinary Bladder Neoplasms/immunology , Animals , Macrophages/metabolism , Macrophages/drug effects , BCG Vaccine/pharmacology , BCG Vaccine/therapeutic use , Signal Transduction/drug effects , Humans , Cell Line, Tumor , Apoptosis/drug effects , Tumor Necrosis Factor-alpha/metabolism , Tumor Microenvironment
8.
Mycopathologia ; 176(3-4): 183-9, 2013 Oct.
Article in English | MEDLINE | ID: mdl-23943428

ABSTRACT

The possible role of sialic acids in host cells-fungi interaction and their association with glycoproteins were evaluated using a clinical isolate of the dimorphic fungus Mucor polymorphosporus. Lectin-binding assays with spores and yeast cells denoted the presence of surface sialoglycoconjugates containing 2,3- and 2,6-linked sialylglycosyl groups. Western blotting with peroxidase-labeled Limulus polyphemus agglutinin revealed the occurrence of different sialoglycoprotein types in both cell lysates and cell wall protein extracts of mycelia, spores, and yeasts of M. polymorphosporus. Sialic acids contributed to the surface negative charge of spores and yeast forms as evaluated by adherence to a cationic substrate. Sialidase-treated spores were less resistant to phagocytosis by human neutrophils and monocytes from healthy individuals than control (untreated) fungal suspensions. The results suggest that sialic acids are terminal units of various glycoproteins of M. polymorphosporus, contributing to negative charge of yeasts and spore cells and protecting infectious propagules from destruction by host cells.


Subject(s)
Blood/immunology , Mucor/chemistry , Mucor/immunology , Phagocytes/immunology , Phagocytosis/drug effects , Sialoglycoproteins/immunology , Sialoglycoproteins/metabolism , Humans , Hyphae/chemistry , Hyphae/immunology , Lectins/metabolism , Mucor/isolation & purification , Mucormycosis/microbiology , Protein Binding , Spores, Fungal/chemistry , Spores, Fungal/immunology , Static Electricity
9.
Molecules ; 18(1): 1128-37, 2013 Jan 16.
Article in English | MEDLINE | ID: mdl-23325101

ABSTRACT

Croton cajucara is a shrub native to the Amazon region locally known as "sacaca". Two morphotypes are known: white and red "sacaca". The essential oils (EO) obtained by hydrodistillation from leaves of the red morphotype were, in general, rich in 7-hydroxycalamenene (28.4%-37.5%). The effectiveness of these EO regarding the antimicrobial activity against pathogenic microorganisms was initially investigated by the drop test method, showing significant inhibition zones. Among the microorganisms tested, the essential oils rich in 7-hydroxycalamenene were more effective against methicillin resistant Staphylococcus aureus (MRSA), Enterococcus faecalis, Mycobacterium tuberculosis, M. smegmatis, Mucor circinelloides and Rhizopus oryzae. The minimum inhibitory concentrations (MIC) of the oils were determined using the broth dilution assay. It was possible to observe that 7-hydroxycalamenene-rich oils presented high antimicrobial activity, with MIC of 4.76 × 10⁻³ µg/mL for MRSA, 4.88 µg/mL for M. tuberculosis, 39.06 µg/mL for M. smegmatis, and 0.152 µg/mL for R. oryzae and 3.63 × 10⁻8 µg/mL for M. circinelloides. The antioxidant activity of this EO suggests that 7-hydroxycalamenene provides more antioxidant activity according with EC(50) less than 63.59 µg/mL. Considering the bioactive potential of EOs and 7-hydroxycalamenene could be of great interest for development of antimicrobials for therapeutic use in treatment of bacterial and fungal infections in humans and/or veterinary practice.


Subject(s)
Anti-Bacterial Agents/pharmacology , Croton/chemistry , Free Radical Scavengers/chemistry , Oils, Volatile/pharmacology , Plant Oils/pharmacology , Sesquiterpenes/pharmacology , Anti-Bacterial Agents/chemistry , Anti-Bacterial Agents/isolation & purification , Biphenyl Compounds/chemistry , Enterococcus faecalis/drug effects , Free Radical Scavengers/isolation & purification , Free Radical Scavengers/pharmacology , Free Radicals/chemistry , Methicillin-Resistant Staphylococcus aureus/drug effects , Microbial Sensitivity Tests , Mycobacterium tuberculosis/drug effects , Oils, Volatile/chemistry , Oils, Volatile/isolation & purification , Picrates/chemistry , Plant Oils/chemistry , Plant Oils/isolation & purification , Sesquiterpenes/chemistry , Sesquiterpenes/isolation & purification
10.
Heliyon ; 9(8): e18846, 2023 Aug.
Article in English | MEDLINE | ID: mdl-37593602

ABSTRACT

Studying changes in temperature is fundamental for understanding its interactions with the environment and biodiversity. However, studies in mountainous areas are few, due to their complex formation and the difficulty of obtaining local data. We analysed changes in temperature over time in Montesinho Natural Park (MNP) (Bragança, Portugal), an important conservation area due to its high level of biodiversity. Specifically, we aimed to analyse: i) whether temperature increased in MNP over time, ii) what environmental factors influence the Land Surface Temperature (LST), and iii) whether vegetation is related to changes in temperature. We used annual summer and winter mean data acquired from the Moderate-Resolution Imaging Spectroradiometer (MODIS) datasets/products (e.g. LST, gathered at four different times: 11am, 1pm, 10pm and 2am, Enhance vegetation index - EVI, and Evapotranspiration - ET), available on the cloud-based platform Google Earth Engine between 2003 and 2021). We analysed the dynamics of the temporal trend patterns between the LST and local thermal data (from a weather station) by correlations; the trends in LST over time with the Mann-Kendall trend test; and the stability of hot spots and cold spots of LST with Local Statistics of Spatial Association (LISA) tests. The temporal trend patterns between LST and Air Temperature (Tair) data were very similar (ρ > 0.7). The temperature in the MNP remained stable over time during summer but increased during winter nights. The biophysical indices were strongly correlated with the summer LST at 11am and 1pm. The LISA results identified hot and cold zones that remained stable over time. The remote-sensed data proved to be efficient in measuring changes in temperature over time.

11.
Biomedicines ; 10(11)2022 Oct 28.
Article in English | MEDLINE | ID: mdl-36359265

ABSTRACT

The gut microbiota refers to bacteria lodges in the gastrointestinal tract (GIT) that interact through various complex mechanisms. The disturbance of this ecosystem has been correlated with several diseases, such as neurologic, respiratory, cardiovascular, and metabolic diseases and cancer. Therefore, the modulation of the gut microbiota has emerged as a potential therapeutic tool; of the various forms of gut microbiota modulation, fecal microbiota transplantation (FMT) is the most approached. This recent technique involves introducing fecal material from a healthy donor into the patient's gastrointestinal tract, aiming to restore the gut microbiota and lead to the resolution of symptoms. This procedure implies a careful donor choice, fine collection and handling of fecal material, and a balanced preparation of the recipient and consequent administration of the prepared content. Although FMT is considered a biological therapy with promising effects, side effects such as diarrhea and abdominal pain have also been claimed, making this a significant challenge in the application of FMT. Bearing this in mind, the present review aims to summarize the recent advances in understanding FMT mechanisms, their impact across different pathological conditions, and the associated side effects, emphasizing the most recent published data.

12.
Case Rep Hematol ; 2022: 7178065, 2022.
Article in English | MEDLINE | ID: mdl-35535243

ABSTRACT

Iatrogenic immunodeficiency-associated lymphoproliferative disorders (LPDs) are heterogeneous clinicopathological entities developing in patients receiving immunosuppression. Outside the posttransplant setting, methotrexate (MTX), a drug commonly used for the treatment of autoimmune diseases, is an immunosuppressive agent frequently reported to be associated with LPD. MTX-associated LPD (MTX-LPD) includes a spectrum of lymphocytic proliferations, ranging from polyclonal hyperplasia to malignant lymphoma. MTX-LPD diagnosis can be challenging, as signs and symptoms are often nonspecific and may overlap with those of several other conditions, including exacerbation of the underlying autoimmune disease. Spontaneous regression of LPD after MTX discontinuation is characteristic of MTX-LPD, therefore avoiding chemotherapeutic intervention in a significant proportion of patients. Other cases, however, should receive chemotherapy.

13.
Clin Cancer Res ; 28(6): 1203-1216, 2022 03 15.
Article in English | MEDLINE | ID: mdl-34980600

ABSTRACT

PURPOSE: Cetuximab is an EGFR-targeted therapy approved for the treatment of RAS wild-type (WT) metastatic colorectal cancer (mCRC). However, about 60% of these patients show innate resistance to cetuximab. To increase cetuximab efficacy, it is crucial to successfully identify responder patients, as well as to develop new therapeutic approaches to overcome cetuximab resistance. EXPERIMENTAL DESIGN: We evaluated the value of EGFR effector phospholipase C gamma 1 (PLCγ1) in predicting cetuximab responses, by analyzing progression-free survival (PFS) of a multicentric retrospective cohort of 94 treated patients with mCRC (log-rank test and Cox regression model). Furthermore, we used in vitro and zebrafish xenotransplant models to identify and target the mechanism behind PLCγ1-mediated resistance to cetuximab. RESULTS: In this study, levels of PLCγ1 were found increased in RAS WT tumors and were able to predict cetuximab responses in clinical samples and in vitro and in vivo models. Mechanistically, PLCγ1 expression was found to bypass cetuximab-dependent EGFR inhibition by activating ERK and AKT pathways. This novel resistance mechanism involves a noncatalytic role of PLCγ1 SH2 tandem domains in the propagation of downstream signaling via SH2-containing protein tyrosine phosphatase 2 (SHP2). Accordingly, SHP2 inhibition sensitizes PLCγ1-resistant cells to cetuximab. CONCLUSIONS: Our discoveries reveal the potential of PLCγ1 as a predictive biomarker for cetuximab responses and suggest an alternative therapeutic approach to circumvent PLCγ1-mediated resistance to cetuximab in patients with RAS WT mCRC. In this way, this work contributes to the development of novel strategies in the medical management and treatment of patients with mCRC.


Subject(s)
Colonic Neoplasms , Colorectal Neoplasms , Protein Tyrosine Phosphatase, Non-Receptor Type 11/metabolism , Rectal Neoplasms , Animals , Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Cetuximab/pharmacology , Cetuximab/therapeutic use , Colonic Neoplasms/drug therapy , Colorectal Neoplasms/drug therapy , Colorectal Neoplasms/genetics , ErbB Receptors/genetics , Humans , Mutation , Phospholipase C gamma/genetics , Proto-Oncogene Proteins p21(ras) , Rectal Neoplasms/drug therapy , Retrospective Studies , Zebrafish
14.
ACS Pharmacol Transl Sci ; 5(11): 1156-1168, 2022 Nov 11.
Article in English | MEDLINE | ID: mdl-36407952

ABSTRACT

Bruton's tyrosine kinase (BTK) is a member of the TEC-family kinases and crucial for the proliferation and differentiation of B-cells. We evaluated the therapeutic potential of a covalent inhibitor (JS25) with nanomolar potency against BTK and with a more desirable selectivity and inhibitory profile compared to the FDA-approved BTK inhibitors ibrutinib and acalabrutinib. Structural prediction of the BTK/JS25 complex revealed sequestration of Tyr551 that leads to BTK's inactivation. JS25 also inhibited the proliferation of myeloid and lymphoid B-cell cancer cell lines. Its therapeutic potential was further tested against ibrutinib in preclinical models of B-cell cancers. JS25 treatment induced a more pronounced cell death in a murine xenograft model of Burkitt's lymphoma, causing a 30-40% reduction of the subcutaneous tumor and an overall reduction in the percentage of metastasis and secondary tumor formation. In a patient model of diffuse large B-cell lymphoma, the drug response of JS25 was higher than that of ibrutinib, leading to a 64% "on-target" efficacy. Finally, in zebrafish patient-derived xenografts of chronic lymphocytic leukemia, JS25 was faster and more effective in decreasing tumor burden, producing superior therapeutic effects compared to ibrutinib. We expect JS25 to become therapeutically relevant as a BTK inhibitor and to find applications in the treatment of hematological cancers and other pathologies with unmet clinical treatment.

15.
Porto Biomed J ; 6(1): e106, 2021.
Article in English | MEDLINE | ID: mdl-33490701

ABSTRACT

Lately, the gut microbiota has emerged as an important mediator of the development and the outcomes of certain diseases. It's well known that the gut microbiota plays an important role in maintaining human health. Still far from being completely understood and analyzed is the complexity of this ecosystem, although a close relationship between the gut microbiota and cardiovascular diseases (CVD) has been established. A loss of diversity in the microbiota will lead to physiological changes, which can improve inflammatory or infection states like atherosclerosis and hypertension, the basic pathological process of CVD. Targeting the gut microbiota and its metabolites are new and promising strategies for the treatment and prognosis of CVD.

16.
Cells ; 10(8)2021 08 13.
Article in English | MEDLINE | ID: mdl-34440847

ABSTRACT

BACKGROUND: Cancers of the pancreas and biliary tree remain one of the most aggressive oncological malignancies, with most patients relying on systemic chemotherapy. However, effective biomarkers to predict the best therapy option for each patient are still lacking. In this context, an assay able to evaluate individual responses prior to treatment would be of great value for clinical decisions. Here we aimed to develop such a model using zebrafish xenografts to directly challenge pancreatic cancer cells to the available chemotherapies. METHODS: Zebrafish xenografts were generated from a Panc-1 cell line to optimize the pancreatic setting. Pancreatic surgical resected samples, without in vitro expansion, were used to establish zebrafish patient-derived xenografts (zAvatars). Upon chemotherapy exposure, zAvatars were analyzed by single-cell confocal microscopy. RESULTS: We show that Panc-1 zebrafish xenografts are able to reveal tumor responses to both FOLFIRINOX and gemcitabine plus nanoparticle albumin-bound (nab)-paclitaxel in just 4 days. Moreover, we established pancreatic and ampullary zAvatars with patient-derived tumors representative of different histological types. CONCLUSION: Altogether, we provide a short report showing the feasibility of generating and analyzing with single-cell resolution zAvatars from pancreatic and ampullary cancers, with potential use for future preclinical studies and personalized treatment.


Subject(s)
Antineoplastic Agents/therapeutic use , Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Pancreatic Neoplasms/drug therapy , Xenograft Model Antitumor Assays/methods , Albumins/therapeutic use , Animals , Deoxycytidine/analogs & derivatives , Deoxycytidine/therapeutic use , Drug Therapy, Combination , Fluorouracil/therapeutic use , Irinotecan/therapeutic use , Leucovorin/therapeutic use , Oxaliplatin/therapeutic use , Paclitaxel/therapeutic use , Pancreatic Neoplasms/pathology , Tumor Cells, Cultured , Zebrafish , Gemcitabine
17.
Nat Commun ; 12(1): 1156, 2021 02 19.
Article in English | MEDLINE | ID: mdl-33608544

ABSTRACT

Cancer immunoediting is a dynamic process of crosstalk between tumor cells and the immune system. Herein, we explore the fast zebrafish xenograft model to investigate the innate immune contribution to this process. Using multiple breast and colorectal cancer cell lines and zAvatars, we find that some are cleared (regressors) while others engraft (progressors) in zebrafish xenografts. We focus on two human colorectal cancer cells derived from the same patient that show contrasting engraftment/clearance profiles. Using polyclonal xenografts to mimic intra-tumor heterogeneity, we demonstrate that SW620_progressors can block clearance of SW480_regressors. SW480_regressors recruit macrophages and neutrophils more efficiently than SW620_progressors; SW620_progressors however, modulate macrophages towards a pro-tumoral phenotype. Genetic and chemical suppression of myeloid cells indicates that macrophages and neutrophils play a crucial role in clearance. Single-cell-transcriptome analysis shows a fast subclonal selection, with clearance of regressor subclones associated with IFN/Notch signaling and escaper-expanded subclones with enrichment of IL10 pathway. Overall, our work opens the possibility of using zebrafish xenografts as living biomarkers of the tumor microenvironment.


Subject(s)
Colonic Neoplasms/metabolism , Colorectal Neoplasms/metabolism , Immune Evasion , Animals , Cell Line, Tumor , Disease Models, Animal , Heterografts , Homeodomain Proteins/genetics , Humans , Immunity, Innate , Macrophages/metabolism , Mice , Mice, Inbred BALB C , Mice, Inbred C57BL , Tumor Microenvironment , Xenograft Model Antitumor Assays , Zebrafish
18.
Med Mycol ; 48(2): 278-84, 2010 Mar.
Article in English | MEDLINE | ID: mdl-20141371

ABSTRACT

Complement activation by spores of Mucor ramosissimus, Mucor plumbeus and Mucor circinelloides was studied using absorbed human serum in the presence or absence of chelators (EGTA or EDTA). We found that the spore caused full complement activation when incubated with EGTA-Mg2+ or without chelators, indicating that the alternative pathway is mainly responsible for this response. In order to compare activation profiles from each species, ELISAs for C3 and C4 fragments, mannan binding lectin (MBL), C-reactive protein (CRP) and IgG studies were carried out. All proteins were present on the species tested. Immunofluorescence tests demonstrated the presence of C3 fragments on the surface of all samples, which were confluent throughout fungal surfaces. The same profile of C3, C4, MBL, CRP and IgG deposition, observed in all species, suggests a similar activation behavior for these species.


Subject(s)
Complement Activation/immunology , Mucor/physiology , Spores, Fungal/immunology , C-Reactive Protein/metabolism , Complement C3/metabolism , Complement C4/metabolism , Edetic Acid , Egtazic Acid , Enzyme-Linked Immunosorbent Assay , Fluorescent Antibody Technique, Direct , Humans , Immunoglobulin G/metabolism , Mannose-Binding Lectin/metabolism , Mucor/immunology
19.
Porto Biomed J ; 5(2)2020.
Article in English | MEDLINE | ID: mdl-33299942

ABSTRACT

BACKGROUND: For almost a century it has been recognized that human possess a varied and dens microbial ecosystem called the human microbiota, yet we are still beginning to understand many of the roles that these microorganisms play in human health and development. It is thought that under certain circumstances such as dysbiosis, the microbiota can cause diseases, where the central nervous system (CNS) has an important relevance and where the "gut-brain axis" will play a major role. AIMS: This review investigated the influence of the gut microbiota on brain function, trying to demonstrate whether dysbiosis influences CNS diseases or whether it is the disease that causes dysbiosis, highlighting the existing literature within this field. METHODS: We performed a systematic literature search in EMBASE, PubMed, and Cochrane combining the terms "gut microbiota," "dysbiosis," and "CNS diseases" to identify those whom reported some influence or relation between dysbiosis of gut microbiota and CNS diseases. For the present systematic review, we only included systematic reviews or meta-analysis. RESULTS: The EMBASE, PubMed, and Cochrane were systematically searched, considering only systematic reviews or meta-analysis. Nine studies comprising 705 articles were included in this review. Those 9 systematic reviews consist in 2 about autism spectrum disorder, 1 in dementia, 1 in depression, 2 in autoimmune diseases, 1 in schizophrenia, and 2 in some altered brain function. Available data characterizing several neural diseases demonstrate a significant correlation between dysbiosis and CNS diseases, strengthen the evidence that dysbiosis of gut microbiota may correlate with abnormalities in CNS patients. CONCLUSIONS: Although there is a clear need for more investigations to better understand the role of the gut microbiota in CNS diseases, the modulation of the nervous system by the microbiota is clear, continuing to be the subject of continuous research. We need to fully understand the mechanisms by which the microbiota interacts with the human brain, and therefore what's the connection between dysbiosis and pathologies such depression, dementia, autism, or schizophrenia.

20.
Commun Biol ; 3(1): 299, 2020 06 10.
Article in English | MEDLINE | ID: mdl-32523131

ABSTRACT

Despite promising preclinical results, average response rates to anti-VEGF therapies, such as bevacizumab, are reduced for most cancers, while incurring in remarkable costs and side effects. Currently, there are no biomarkers available to select patients that can benefit from this therapy. Depending on the individual tumor, anti-VEGF therapies can either block or promote metastasis. In this context, an assay able to predict individual responses prior to treatment, including the impact on metastasis would prove of great value to guide treatment options. Here we show that zebrafish xenografts are able to reveal different responses to bevacizumab in just 4 days, evaluating not only individual tumor responses but also the impact on angiogenesis and micrometastasis. Importantly, we perform proof-of-concept experiments where clinical responses in patients were compared with their matching zebrafish Patient-Derived Xenografts - zAvatars, opening the possibility of using the zebrafish model to screen bevacizumab therapy in a personalized manner.


Subject(s)
Angiogenesis Inhibitors/pharmacology , Bevacizumab/pharmacology , High-Throughput Screening Assays/methods , Neovascularization, Pathologic/drug therapy , Triple Negative Breast Neoplasms/drug therapy , Animals , Apoptosis , Cell Proliferation , Female , Humans , Neoplasm Metastasis , Neovascularization, Pathologic/metabolism , Neovascularization, Pathologic/pathology , Triple Negative Breast Neoplasms/metabolism , Triple Negative Breast Neoplasms/pathology , Tumor Cells, Cultured , Xenograft Model Antitumor Assays , Zebrafish
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