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Background: Schistosoma mansoni infection poses a substantial public health challenge globally, and the World Health Organization (WHO) aims for the elimination of schistosomiasis by 2030. This study aimed to assess the current prevalence of human S. mansoni infection in endemic regions worldwide between 2010 and 2024. Methods: We conducted a comprehensive search in PubMed/Medline and Scopus databases as well as other public sources from 1 January 2010 to 15 July 2024. Population-based studies reporting the prevalence of S. mansoni infection were eligible. We undertook a random-effects meta-analysis to estimate pooled prevalences with 95% confidence intervals (CIs) in WHO-defined regions and assessed potential risk factors associated with S. mansoni infection. The protocol for this study was registered on PROSPERO (CRD42023438455). Findings: We identified a total of 542 eligible studies involving 1,163,866 individuals who had been tested for S. mansoni infection in 38 countries. The overall, pooled global prevalence of S. mansoni infection in endemic region was 14.8% (95% CI, 13.5%-16.1%). The pooled prevalences (95% CI) in specific regions were: 15.3% (13.9-16.8%) in sub-Saharan Africa, 12.4% (8.9-16.4%) in South America and 9.5% (5.4-14.6%) in the Eastern Mediterranean region. There was a 52.6% decrease in prevalence of S. mansoni infection and a 37% decrease in high-intensity infection for studies conducted between 2010 and 2014 compared to those conducted between 2020 and 2023. The present analysis revealed that factors including male gender, bathing or swimming in natural water bodies, crossing rivers or lakes, and engaging in water irrigation activities such as fishing, working in rice paddies or maintaining irrigation canals were significantly associated with S. mansoni infection. Interpretation: The findings of this investigation revealed that, despite a decline in prevalence and high-intensity infection, 7-12% of people in endemic regions, notably in sub-Saharan Africa, remained affected by schistosomiasis mansoni between 2020 and 2024. This study provides data of relevance to policymakers to support efforts to eliminate this disease. Funding: This study received no funding.
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5-Fluorouracil (5-FU) is an antimetabolite chemotherapeutic agent that can cause oxidative stress and complications in normal organs, including the reproductive system. This study was conducted to investigate the effect of melatonin (MEL) on 5-FU-induced reproductive toxicity in male rats. Male Wistar rats weighing 180 ± 20 g were divided into five groups: control, 5-FU (50 mg/kg), 5-FU + MEL (2.5, 5 & 10 mg/kg). The testes and prostates were removed, and histopathological aspects, biochemical markers, and gene expression were investigated. The effect of 5-FU on the normal TM4 cell line (murine testicular Sertoli line) and co-treatment of 5-FU and MEL were studied using MTT assay. Results showed that MEL prevented cell death in the TM4 cell line induced by 5-FU. MEL also reduced edema, hyperemia, and vacuolization in testis and prostate tissues induced by 5-FU. Additionally, MEL increased the activity of antioxidant enzymes and reduced the levels of MDA (p < 0.0001) and MPO (p < 0.0001). The levels of testosterone (p < 0.01) and the number of spermatocytes and spermatogonia (p < 0.0001) were increased in groups receiving 5-FU with MEL compared to 5-FU alone. The prostate-specific antigen (PSA) level in prostate samples was lower in the groups receiving 5-FU with MEL compared to the 5-FU group. Furthermore, the genes expression of COX-2 and TNF-α in testis tissues was reduced in the presence of MEL. in conclusion, the antioxidant property of MEL can protect the male reproductive system against 5-FU toxicity, as evidenced by the improved histopathological and biochemical parameters, as well as the reduced gene expression of COX-2 and TNF- α genes.
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Introduction: Diabetes is associated with several debilitating complications, including the development of diabetic foot ulcers (DFUs), which can have serious consequences. This study emphasizes a multidisciplinary approach, providing a thorough overview of DFU pathogenesis and available treatments. Methods: An extensive literature review, covering studies published between 2000 and 2023, was conducted to gather data on DFU pathophysiology and treatments, including wound dressings, photobiomodulation, off-loading devices, adjunct medicines, and stem cell therapy. Results: DFUs are complicated due to infection, ischemia, and neuropathy. Sufficient wound dressings maintain a moist environment, promoting autolytic debridement and facilitating the healing process. Through cellular mechanisms, photobiomodulation therapy (PBM) was observed to expedite the healing process. Additionally, off-loading devices were invented to reduce ulcer pressure and promote healing. Adjunct therapies such as negative pressure wound therapy and hyperbaric oxygen therapy were identified as valuable tools for enhancing healing outcomes. Furthermore, autologous and allogeneic stem cell treatments exhibited the potential for promoting tissue regeneration and expediting the healing process. Conclusion: The complex pathophysiology of DFUs necessitates a multimodal treatment approach. Essential components include PBM, wound dressings, off-loading devices, adjunct treatments, and stem cell therapy.
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Small extracellular vesicles (sEVs; <200 nm) that contain lipids, nucleic acids, and proteins are considered promising biomarkers for a wide variety of diseases. Conventional methods for sEV isolation from blood are incompatible with routine clinical workflows, significantly hampering the utilization of blood-derived sEVs in clinical settings. Here, we present a simple, viscoelastic-based microfluidic platform for label-free isolation of sEVs from human blood. The separation performance of the device is assessed by isolating fluorescent sEVs from whole blood, demonstrating purities and recovery rates of over 97 and 87%, respectively. Significantly, our viscoelastic-based microfluidic method also provides for a remarkable increase in sEV yield compared to gold-standard ultracentrifugation, with proteomic profiles of blood-derived sEVs purified by both methods showing similar protein compositions. To demonstrate the clinical utility of the approach, we isolate sEVs from blood samples of 20 patients with cancer and 20 healthy donors, demonstrating that elevated sEV concentrations can be observed in blood derived from patients with cancer.
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Vesículas Extracelulares , Neoplasias , Humanos , Microfluídica , Proteômica , CorantesRESUMO
OBJECTIVES: Rapidly growing evidence suggests that immune cells play a key role in determining tumor progression. Tumor cells are surrounded by a microenvironment composed of different cell populations including immune cells. The cross talk between tumor cells and the neighboring microenvironment is an important factor to take into account while designing tumor therapies. Despite significant advances in immunotherapy strategies, a relatively small proportion of patients have successfully responded to them. Therefore, the search for safe and efficient drugs, which could be used alongside conventional therapies to boost the immune system against tumors, is an ongoing need. In the present work, the modulatory effects of melatonin on different components of tumor immune microenvironment are reviewed. METHODS: A thorough literature review was performed in PubMed, Scopus, and Web of Science databases. All published papers in English on tumor immune microenvironment and the relevant modulatory effects of melatonin were scrutinized. RESULTS: Melatonin modulates macrophage polarization and prevents M2 induction. Moreover, it prevents the conversion of fibroblasts into cancer-associated fibroblasts (CAFs) and prevents cancer cell stemness. In addition, it can affect the payload composition of tumor-derived exosomes (TEXs) and their secretion levels to favor a more effective anti-tumor immune response. Melatonin is a safe molecule that affects almost all components of the tumor immune microenvironment and prevents them from being negatively affected by the tumor. CONCLUSION: Based on the effects of melatonin on normal cells, tumor cells and microenvironment components, it could be an efficient compound to be used in combination with conventional immune-targeted therapies to increase their efficacy.
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Fibroblastos Associados a Câncer , Melatonina , Neoplasias , Humanos , Melatonina/farmacologia , Melatonina/uso terapêutico , Fibroblastos/patologia , Fibroblastos Associados a Câncer/patologia , Imunoterapia , Microambiente TumoralRESUMO
PURPOSE: Exosomes are membrane-derived nano-vesicles upregulated in pathological conditions like cancer. Therefore, inhibiting their release is a potential strategy for the development of more efficient combination therapies. Neutral sphingomyelinase 2 (nSMase2) is a key component in exosome release; however, a clinically safe yet efficient nSMase2 inhibitor remains to be used discovered. Accordingly, we made an effort to identify potential nSMase2 inhibitor(s) among the approved drugs. METHODS: Virtual screening was performed and aprepitant was selected for further investigation. To evaluate the reliability of the complex, molecular dynamics were performed. Finally, using the CCK-8 assay in HCT116 cells, the highest non-toxic concentrations of aprepitant were identified and the nSMase2 activity assay was performed to measure the inhibitory activity of aprepitant, in vitro. RESULTS: To validate the screening results, molecular docking was performed, and the retrieved scores were in line with the screening results. The root-mean-square deviation (RMSD) plot of aprepitant-nSMase2 showed proper convergence. Following treatment with different concentrations of aprepitant in both cell-free and cell-dependent assays, nSMase2 activity was remarkably decreased. CONCLUSION: Aprepitant, at a concentration as low as 15 µM, was able to inhibit nSmase2 activity in HCT116 cells without any significant effects on their viability. Aprepitant is therefore suggested to be a potentially safe exosome release inhibitor.
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Exossomos , Neoplasias , Humanos , Esfingomielina Fosfodiesterase , Aprepitanto/farmacologia , Simulação de Acoplamento Molecular , Reprodutibilidade dos Testes , Detecção Precoce de CâncerRESUMO
The extracellular RNA communication consortium (ERCC) is an NIH-funded program aiming to promote the development of new technologies, resources, and knowledge about exRNAs and their carriers. After Phase 1 (2013-2018), Phase 2 of the program (ERCC2, 2019-2023) aims to fill critical gaps in knowledge and technology to enable rigorous and reproducible methods for separation and characterization of both bulk populations of exRNA carriers and single EVs. ERCC2 investigators are also developing new bioinformatic pipelines to promote data integration through the exRNA atlas database. ERCC2 has established several Working Groups (Resource Sharing, Reagent Development, Data Analysis and Coordination, Technology Development, nomenclature, and Scientific Outreach) to promote collaboration between ERCC2 members and the broader scientific community. We expect that ERCC2's current and future achievements will significantly improve our understanding of exRNA biology and the development of accurate and efficient exRNA-based diagnostic, prognostic, and theranostic biomarker assays.
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Exosomal release pathway and autophagy together maintain homeostasis and survival of cells under stressful conditions. Autophagy is a catabolic process through which cell entities, such as malformed biomacromolecules and damaged organelles, are degraded and recycled via the lysosomal-dependent pathway. Exosomes, a sub-type of extracellular vesicles (EVs) formed by the inward budding of multivesicular bodies (MVBs), are mostly involved in mediating communication between cells. The unfolded protein response (UPR) is an adaptive response that is activated to sustain survival in the cells faced with the endoplasmic reticulum (ER) stress through a complex network that involves protein synthesis, exosomes secretion and autophagy. Disruption of the critical crosstalk between EVs, UPR and autophagy may be implicated in various human diseases, including cancers and neurodegenerative diseases, yet the molecular mechanism(s) behind the coordination of these communication pathways remains obscure. Here, we review the available information on the mechanisms that control autophagy, ER stress and EV pathways, with the view that a better understanding of their crosstalk and balance may improve our knowledge on the pathogenesis and treatment of human diseases, where these pathways are dysregulated.
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Exossomos , Autofagia/fisiologia , Estresse do Retículo Endoplasmático/fisiologia , Humanos , Lisossomos , Resposta a Proteínas não DobradasRESUMO
Cell-based therapy and tissue engineering are promising substitutes for liver transplantation to cure end-stage liver disorders. However, the limited sources for healthy and functional cells and poor engraftment rate are main challenges to the cell-based therapy approach. On the other hand, feasibility of production and size of bioengineered tissues are primary bottlenecks in tissue engineering. Here, we induce regeneration in a rat fibrotic liver model by transplanting a natural bioengineered scaffold with a native microenvironment repopulated with autologous stem/progenitor cells. In the main experimental group, a 1 mm3 stromal derived factor-1α (SDF-1α; S) loaded scaffold from decellularized liver extracellular matrix (LEM) was transplanted (Tx) into a fibrotic liver and the endogenous stem/progenitor cells were mobilized via granulocyte colony stimulating factor (G-CSF; G) therapy. Four weeks after transplantation, changes in liver fibrosis and necrosis, efficacy of cell engraftment and differentiation, vasculogenesis, and liver function recovery were assessed in this (LEM-TxSG) group and compared to the other groups. We found significant reduction in liver fibrosis stage in the LEM-TxSG, LEM-TxS and LEM-TxG groups compared to the control (fibrotic) group. Liver necrosis grade, and alanine transaminase (ALT) and aspartate transaminase (AST) levels dramatically reduced in all experimental groups compared to the control group. However, the number of engrafted cells into the transplanted scaffold and ratio of albumin (Alb) positive cells per total incorporated cells were considerably higher in the LEM-TxSG group compared to the LEM-Tx, LEM-TxS and LEM-TxG groups. Serum Alb levels increased in the LEM-Tx, LEM-TxS, and LEM-TxG groups, and was highest in the LEM-TxSG group, which was significantly more than the fibrotic group. Small vessel formation in the LEM-TxSG group was significantly higher than the LEM-Tx and LEM-TxS groups. Totally, these findings support application of the in vivo tissue engineering approach as a possible novel therapeutic strategy for liver fibrosis.
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Methods: Pregnant Wistar rats were randomly assigned into five groups: control, NP (25 mg/kg), NP (25 mg/kg)+MLT (10 mg/kg), NP (25 mg/kg)+MLT (20 mg/kg), and MLT (20 mg/kg). The duration of treatment was 21 days from gestation time. Morris water maze was used to assess learning and memory. NP concentrations of serum and testicular tissue were measured by HPLC. Histological analysis of testicular tissues was done by H&E staining. Results: Behavioral study showed that NP does not impair learning and memory in first-generation rats. Histomorphometric results showed that NP can significantly reduce the cross-sectional area of the seminiferous tubules and the epithelium, the diameter and number of seminiferous tubules, the thickness of the epithelium, and the number of spermatocytes and spermatogonia compared to other groups. MLT reversed the NP-induced histomorphometric. Also, it changes and increased the activity of superoxide dismutase (SOD), total antioxidant capacity (TAC), and catalase (CAT). The level of malondialdehyde (MDA) significantly decreased in MLT-treated groups compared with the NP group. Conclusion: Our finding showed that MLT enhanced the learning process and reduced NP-induced testicular tissue damage through its antioxidants and cytoprotective effects.
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Melatonina , Animais , Antioxidantes/farmacologia , Feminino , Masculino , Melatonina/farmacologia , Estresse Oxidativo , Fenóis/farmacologia , Gravidez , Ratos , Ratos WistarRESUMO
Aims: To study the association between miR-31 expression and clinical outcomes in colorectal cancer. Methods: A systematic search was performed and 16 studies were found eligible. To calculate the combined hazard ratio (HR), the DerSimonian and Laird random-effects model was used. Results: Pooled analysis revealed significant associations between high miR-31 expression and poor overall (HR: 0.68; 95% CI: 0.47-0.97; I2: 68.6%) and progression-free survival (HR: 0.49; 95% CI: 0.33-0.73; I2: 81.1%). High expressers were more likely to have a BRAF mutation. Therapeutic regimen and the mutational status significantly affected the observed associations. Conclusion: We identified that high miR-31 expression is associated with poor overall survival and progression-free survival and has a significant predictive value for anti-EGFR response.
Lay abstract We aim to investigate whether the molecular marker miR-31 is useful in predicting clinical outcomes in colorectal cancer (CRC). We conducted a systematic search in the major scientific databases was performed and 16 studies were found eligible for data extraction.The analysis revealed that high levels of miR-31 in CRC patients are indicative of a shorter survival time. Patients with high miR-31 levels were also more likely to have a mutation in BRAF, an important gene in the pathogenesis and response to treatment of CRC patients. We showed that high levels of miR-31 are associated with shorter survival with a significant predictive value for anti-EGFR response.
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Antineoplásicos , Neoplasias Colorretais , MicroRNAs , Anticorpos Monoclonais/genética , Anticorpos Monoclonais/uso terapêutico , Antineoplásicos/uso terapêutico , Biomarcadores Tumorais/genética , Cetuximab/genética , Cetuximab/uso terapêutico , Neoplasias Colorretais/tratamento farmacológico , Receptores ErbB/genética , Receptores ErbB/metabolismo , Receptores ErbB/uso terapêutico , Humanos , MicroRNAs/metabolismo , Mutação , Prognóstico , Proteínas Proto-Oncogênicas B-raf/genética , Proteínas Proto-Oncogênicas B-raf/uso terapêuticoRESUMO
Circulating tumor cells (CTCs), secreted from primary and metastatic malignancies, hold a wealth of essential diagnostic and prognostic data for multiple cancers. Significantly, the information contained within these cells may hold the key to understanding cancer metastasis, both individually and fundamentally. Accordingly, developing ways to identify, isolate and interrogate CTCs plays an essential role in modern cancer research. Unfortunately, CTCs are typically present in the blood in vanishingly low titers and mixed with other blood components, making their isolation and analysis extremely challenging. Herein, we report the design, fabrication and optimization of a microfluidic device capable of automatically isolating CTCs from whole blood. This is achieved in two steps, via the passive viscoelastic separation of CTCs and white blood cells (WBCs) from red blood cells (RBCs), and subsequent active magnetophoretic separation of CTCs from WBCs. We detail the specific geometries required to balance the elastic and inertial forces required for successful passive separation of RBCs, and the use of computational fluid dynamics (CFD) to optimize active magnetophoretic separation. We subsequently describe the use of magnetic biosilica frustules, extracted from Chaetoceros sp. diatoms, to fluorescently tag CTCs and facilitate magnetic isolation. Finally, we use our microfluidic platform to separate HepG2-derived CTCs from whole blood, demonstrating exceptional CTC recovery (94.6%) and purity (89.7%).
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Trypanosomes are protozoan parasites of class Kinetoplastida. Trypanosoma vivax is one of the organisms that can cause Nagana and Trypanosoma evansi can cause Surra. In Africa, Trypanosoma vivax is mainly transmitted by Glossina spp. (tsetse fly) but it can be transmitted mechanically by other blood-feeding dipters. Trypanosoma evansi is transmitted mechanically and non-dependent to tsetse fly. In this research, T. vivax and T. evansi among camels (Camelus dromedarius) in Yazd, Iran were identified by microscopy and molecular examinations but the sensitivity of microscopy was lower than molecular examinations. Trypanosoma vivax and T. evansi were observed in 4 out of 134 blood film samples (2.98%). The prevalence of Trypanosoma spp. among 134 male camels (C. dromedarius) based on molecular examinations was 30.6% (22.76-38.44% with 95% confidence interval), 25 out of 134 (18.65%) had co-infection of T. evansi and T. vivax, and 16 out of 134 (11.94%) had an infection of T. vivax alone. We provided the first confirmation of infection with T. vivax among camels in Iran, and also in Asia, which has important implications on our knowledge of the occurrence and possible spread of this pathogen at the global level. Investigations in other species such as cattle and sheep are strongly recommended.
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Camelus , Trypanosoma vivax/isolamento & purificação , Tripanossomíase/veterinária , Animais , Irã (Geográfico)/epidemiologia , Masculino , Prevalência , Trypanosoma/isolamento & purificação , Tripanossomíase/epidemiologia , Tripanossomíase/parasitologiaRESUMO
The current era of cancer research has been continuously advancing upon identifying novel aspects of tumorigenesis and the principal mechanisms behind the unleashed proliferation, invasion, drug resistance and immortality of cancer cells in hopes of exploiting these findings to achieve a more effective treatment for cancer. In pursuit of this goal, the identification of the first components of an extremely important regulatory pathway in Drosophila melanogaster that largely determines cell fate during the developmental stages, ended up in the discovery of the highly sophisticated Hippo signaling cascade. Soon after, it was revealed that deregulation of the components of this pathway either via mutations or through epigenetic alterations can be observed in a vast variety of tumors and these alterations greatly contribute to the neoplastic transformation of cells, their survival, growth and resistance to therapy. As more hidden aspects of this pathway such as its widespread entanglement with other major cellular signaling pathways are continuously being uncovered, many researchers have sought over the past decade to find ways of therapeutic interventions targeting the major components of the Hippo cascade. To date, various approaches such as the use of exogenous targeting miRNAs and different molecular inhibitors have been recruited herein, among which naturally occurring compounds have shown a great promise. On such a basis, in the present work we review the current understanding of Hippo pathway and the most recent evidence on targeting its components using natural plant-derived phytochemicals.
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Drosophila melanogaster , Neoplasias , Animais , Transformação Celular Neoplásica , Drosophila melanogaster/genética , Drosophila melanogaster/metabolismo , Via de Sinalização Hippo , Humanos , Neoplasias/tratamento farmacológico , Neoplasias/genética , Neoplasias/metabolismo , Compostos Fitoquímicos/farmacologia , Compostos Fitoquímicos/uso terapêutico , Proteínas Serina-Treonina Quinases , Transdução de Sinais/genéticaRESUMO
T cells sense and respond to their local environment at the nanoscale by forming small actin-rich protrusions, called microvilli, which play critical roles in signaling and antigen recognition, particularly at the interface with the antigen presenting cells. However, the mechanism by which microvilli contribute to cell signaling and activation is largely unknown. Here, we present a tunable engineered system that promotes microvilli formation and T cell signaling via physical stimuli. We discovered that nanoporous surfaces favored microvilli formation and markedly altered gene expression in T cells and promoted their activation. Mechanistically, confinement of microvilli inside of nanopores leads to size-dependent sorting of membrane-anchored proteins, specifically segregating CD45 phosphatases and T cell receptors (TCR) from the tip of the protrusions when microvilli are confined in 200-nm pores but not in 400-nm pores. Consequently, formation of TCR nanoclustered hotspots within 200-nm pores allows sustained and augmented signaling that prompts T cell activation even in the absence of TCR agonists. The synergistic combination of mechanical and biochemical signals on porous surfaces presents a straightforward strategy to investigate the role of microvilli in T cell signaling as well as to boost T cell activation and expansion for application in the growing field of adoptive immunotherapy.
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Expressão Gênica/imunologia , Ativação Linfocitária/imunologia , Microvilosidades/imunologia , Linfócitos T/imunologia , Actinas/imunologia , Células Apresentadoras de Antígenos/imunologia , Células Cultivadas , Humanos , Receptores de Antígenos de Linfócitos T/imunologia , Transdução de Sinais/imunologiaRESUMO
Rapidly growing interest in the study of extracellular vesicles (EVs) has led to the accumulation of evidence on their critical roles in various pathologies, as well as opportunities to design novel therapeutic EV-based applications. Efficiently exploiting the constantly expanding knowledge of the biology and function of EVs requires a deep understanding of the various possible strategies of using EVs for therapeutic purposes. Accordingly, in the present work, we have narrowed the broad therapeutic potential of EVs and consider the similarities and differences of various strategies as we articulate three major aspects (i.e., a triad) of their therapeutic uses: (i) EVs as drug targets, whereby we discuss therapeutic targeting of disease-promoting EVs; (ii) EVs as drugs, whereby we consider the natural medicinal properties of EVs and the available options for their optimization; and (iii) EVs as drug carriers, whereby we highlight the advantages of EVs as vehicles for efficacious drug delivery of natural compounds. Finally, after conducting a comprehensive review of the latest literature on each of these aspects, we outline opportunities, limitations, and potential solutions.
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Fatores Biológicos/metabolismo , Portadores de Fármacos/metabolismo , Sistemas de Liberação de Medicamentos/métodos , Vesículas Extracelulares/metabolismo , Animais , Fatores Biológicos/administração & dosagem , Portadores de Fármacos/administração & dosagem , Exossomos/metabolismo , Humanos , Doenças Vasculares/sangue , Doenças Vasculares/tratamento farmacológicoRESUMO
Aims: Acute myeloblastic leukemia (AML) is the most common type of acute leukemia in adults. Despite numerous treatment strategies including chemotherapy and radiotherapy, a large number of patients do not respond to treatment and experience relapse. The main problem of these patients is the development of resistance to anti-cancer drugs. Therefore, any endeavor to reduce drug resistance in these patients is of high priority. In general, several mechanisms such as changes in drug metabolic pathways, drug inactivation, drug target alterations and reduced drug accumulation in the cells contribute to drug resistance of cancer cells. In this context, evidence suggests that exosomes could reduce drug resistance by removing drugs from their parent cells. In the present study, we aimed to investigate the effects of exosome release inhibition on the resistance of U937 cells to PEGylated liposomal doxorubicin (PLD). Main Methods: In order to find a suitable ABCG2 (ATP-binding cassette sub-family G member 2) transporter substrate, virtual screening was performed among a list of drugs used in leukemia and PLD was selected. U937 cells were treated with PLD with/without co-treatment with the exosome release inhibitor, GW4869. Released exosomes within different study groups were isolated and characterized to determine the differences between groups. Doxorubicin presence in the isolated exosomes was also measured by high performance liquid chromatography (HPLC) to confirm drug export through the exosomes. Finally, the effect of exosome inhibition on the cytotoxicity of PLD on U937 cells was determined using different cytotoxicity assays including the standard lactate dehydrogenase (LDH) release assay and the flow cytometric analysis of apoptotic and non-apoptotic cell death. Key Findings: GW4869 treatment caused a significant decrease in the exosome release of U937 cells compared to the untreated cells, as evidenced by the reduction of the protein content of the isolated exosomes (P<0.05). Co-treatment with GW4869 significantly increased cytotoxic cell death in the groups treated with 0.5 and 1 µM PLD, compared to the same groups without GW4869 co-treatment (P<0.05). Interestingly, co-treatment with GW4896 and 0.5 µM PLD was enough to induce the same cytotoxic effect as that of the sole 1 µM PLD group. Significance: Our findings showed that U937 cells increase their resistance against the cytotoxic effects of PLD through the exosome-mediated expelling of the drug. Inhibition of exosome release could prevent PLD efflux and consequently increase the vulnerability of the U937 cells to the cytotoxic effects of PLD. Our results along with prior studies indicate that the integration of exosome release inhibitors into the common PLD-containing chemotherapy regimens could significantly lower the required concentrations of the drug and consequently reduce its associated side effects. Further studies are warranted to identify clinically safe inhibitors and investigate their clinical efficacy.
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Membro 2 da Subfamília G de Transportadores de Cassetes de Ligação de ATP/antagonistas & inibidores , Compostos de Anilina/farmacologia , Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Compostos de Benzilideno/farmacologia , Doxorrubicina/análogos & derivados , Exossomos/efeitos dos fármacos , Leucemia Mieloide Aguda/tratamento farmacológico , Proteínas de Neoplasias/antagonistas & inibidores , Membro 2 da Subfamília G de Transportadores de Cassetes de Ligação de ATP/metabolismo , Morte Celular/efeitos dos fármacos , Doxorrubicina/metabolismo , Doxorrubicina/farmacologia , Resistencia a Medicamentos Antineoplásicos , Exossomos/metabolismo , Exossomos/patologia , Humanos , Leucemia Mieloide Aguda/metabolismo , Leucemia Mieloide Aguda/patologia , Proteínas de Neoplasias/metabolismo , Polietilenoglicóis/metabolismo , Polietilenoglicóis/farmacologia , Células U937RESUMO
Hematological malignancies are classified as a heterogeneous category of cancers with various degrees of incidence and prognosis and different etiologies. Due to their aggressive essence they should be diagnosed as early as possible to improve prognosis, treatment outcome and survival. Bases on the limitations of previously identified biomarkers in terms of sensitivity, specificity and predictability, it is necessary to develop new diagnostic tools and biomarkers for the early diagnosis of hematological malignancies. Exosomes are nanovesicles secreted by almost all cell types in both physiological and pathological conditions. They play major roles in intercellular communication and are recently being considered as disease biomarkers. These nanovesicles carry proteins, lipids and nucleic acids like microRNAs (miRNAs). miRNAs are small noncoding RNAs, which act as translational suppressors via regulating protein-coding genes. The aberrant expression of miRNAs has been shown in various conditions including hematological malignancies. Moreover, it is now known that tumor cells secrete higher amounts of exosomes compared to normal cells. The idea of using exosomal miRNAs in serum as biomarkers is based on their surprisingly high stability and specificity. In the present paper, we reviewed and recommended exosomal miRNA panels including (miR-150, miR-155 and miR-1246), (miR-17-5p, miR-20a-5p, miR-16-5p and miR-5a-5p), (miR-18a, Let-7b) and (miR192-5p, miR21-5p, miR320b and Let-7d), for their potential to be used as non-invasive biomarkers in different hematological malignancies such as multiple myeloma, leukemia, and lymphoma.
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Biomarcadores Tumorais/sangue , Neoplasias Hematológicas/sangue , MicroRNAs/sangue , Exossomos/metabolismo , Exossomos/patologia , Neoplasias Hematológicas/metabolismo , Neoplasias Hematológicas/patologia , HumanosRESUMO
The biological functions of melatonin range beyond the regulation of the circadian rhythm. With regard to cancer, melatonin's potential to suppress cancer initiation, progression, angiogenesis and metastasis as well as sensitizing malignant cells to conventional chemo- and radiotherapy are among its most interesting effects. The targets at which melatonin initiates its anti-cancer effects are in common with those of a majority of existing anti-cancer agents, giving rise to the notion that this molecule is a pleiotropic agent sharing many features with other antineoplastic drugs in terms of their mechanisms of action. Among these common mechanisms of action are the regulation of several major intracellular pathways including mitogen-activated protein kinase (MAPK), extracellular signal-regulated kinase (ERK) and protein kinase B (AKT/PKB) signaling. The important mediators affected by melatonin include cyclins, nuclear factor-κB (NF-κB), heat shock proteins (HSPs) and c-Myc, all of which can serve as potential targets for cancer drugs. Melatonin also exerts some of its anti-cancer effects via inducing epigenetic modifications, DNA damage and mitochondrial disruption in malignant cells. The regulation of these mediators by melatonin mitigates tumor growth and invasiveness via modulating their downstream responsive genes, housekeeping enzymes, telomerase reverse transcriptase, apoptotic gene expression, angiogenic factors and structural proteins involved in metastasis. Increasing our knowledge on how melatonin affects its target sites will help find ways of exploiting the beneficial effects of this ubiquitously-acting molecule in cancer therapy. Acknowledging this, here we reviewed the most studied target pathways attributed to the anti-cancer effects of melatonin, highlighting their therapeutic potential.