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BACKGROUND: Angiogenesis, the biological mechanism by which new blood vessels are generated from existing ones, plays a vital role in growth and development. Effective preclinical screening is necessary for the development of medications that may enhance or inhibit angiogenesis in the setting of different disorders. Traditional in vitro and, in vivo models of angiogenesis are laborious and time-consuming, necessitating advanced infrastructure for embryo culture. MAIN BODY: A challenge encountered by researchers studying angiogenesis is the lack of appropriate techniques to evaluate the impact of regulators on the angiogenic response. An ideal test should possess reliability, technical simplicity, easy quantifiability, and, most importantly, physiological relevance. The CAM model, leveraging the extraembryonic membrane of the chicken embryo, offers a unique combination of accessibility, low cost, and rapid development, making it an attractive option for angiogenesis assays. This review evaluates the strengths and limitations of the CAM model in the context of its anatomical and physiological properties, and its relevance to human pathophysiological conditions. Its abundant capillary network makes it a common choice for studying angiogenesis. The CAM assay serves as a substitute for animal models and offers a natural setting for developing blood vessels and the many elements involved in the intricate interaction with the host. Despite its advantages, the CAM model's limitations are notable. These include species-specific responses that may not always extrapolate to humans and the ethical considerations of using avian embryos. We discuss methodological adaptations that can mitigate some of these limitations and propose future directions to enhance the translational relevance of this model. This review underscores the CAM model's valuable role in angiogenesis research and aims to guide researchers in optimizing its use for more predictive and robust preclinical studies. CONCLUSION: The highly vascularized chorioallantoic membrane (CAM) of fertilized chicken eggs is a cost-effective and easily available method for screening angiogenesis, in comparison to other animal models.
Assuntos
Membrana Corioalantoide , Neovascularização Fisiológica , Membrana Corioalantoide/irrigação sanguínea , Animais , Embrião de Galinha , Humanos , Neovascularização Patológica , Galinhas , AngiogêneseRESUMO
BACKGROUND: Angiogenesis is an important hallmark of Glioblastoma (GBM) marked by elevated vascular endothelial growth factor-A (VEGF-A) and its receptor 2 (VEGFR-2). As previously reported nimbolide (NBL), trans-chalcone (TC) and piperine (PPR) possess promising antiangiogenic activity in several cancers however, their comparative efficacy and mechanism of antiangiogenic activity in GBM against VEGFR-2 has not been elucidated. METHODS: 2D and 3D spheroids cultures of U87 (Uppsala 87 Malignant Glioma) were used for evaluation of non-cytotxoic dose for anti-angiogenic activity. The antiangiogenic effect was investigated by the GBM U87 cell line bearing chick CAM model. Excised U87 xenografts were histologically examined for blood vascular density by histochemistry. Reverse transcriptase polymerase chain reaction (RT-PCR) was used to detect the presence of avian and human VEGF-A and VEGFR-2 mRNA transcripts. RESULTS: Using 2D and 3D spheroid models, the non-cytotoxic dose of NBL, TC and PPR was ≤ 11 µM. We found NBL, TC and PPR inhibit U87-induced neoangiogenesis in a dose-dependent manner in the CAM stand-alone model as well as in CAM U87 xenograft model. The results also indicate that these natural compounds inhibit the expression of notable angiogenic factors, VEGF-A and VEGFR-2. A positive correlation was found between blood vascular density and VEGF-A as well as VEGFR-2 transcripts. CONCLUSION: Taken together, NBL, TC and PPR can suppress U87-induced neoangiogenesis via a reduction in VEGF-A and its receptor VEGFR-2 transcript expression at noncytotoxic concentrations. These phytochemicals showed their utility as adjuvants to GBM therapy, with Piperine demonstrating superior effectiveness among them all.
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Chalconas , Glioblastoma , Humanos , Glioblastoma/patologia , Fator A de Crescimento do Endotélio Vascular/genética , Fator A de Crescimento do Endotélio Vascular/metabolismo , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/genética , Inibidores da Angiogênese/farmacologia , Inibidores da Angiogênese/uso terapêutico , Neovascularização Patológica/tratamento farmacológico , Linhagem Celular TumoralRESUMO
BACKGROUND: The role of ATF2 in colon cancer (CC) is controversial. Recently, we reported that low ATF2 expression is characteristic of highly invasive tumors, suggesting that ATF2 might also be involved in therapy resistance. 5-Fluorouracil (5-FU) is the best-known chemotherapeutic drug for CC, but drug resistance affects its curative effect. To date, the role of ATF2 in the 5-FU response remains elusive. METHODS/RESULTS: For our study, we had available HCT116 cells (wild-type p53) and HT29 colon tumor cells (mutant p53) and their corresponding CRISPRâCas9-generated ATF2-KO clones. We observed that loss of ATF2 triggered dose- and time-dependent 5-FU resistance in HCT116 cells by activating the DNA damage response (DDR) pathway with high p-ATRThr1989 and p-Chk1Ser317 levels accompanied by an increase in the DNA damage marker γ-H2AX in vitro and in vivo using the chicken chorioallantoic membrane (CAM) model. Chk1 inhibitor studies causally displayed the link between DDR and drug resistance. There were contradictory findings in HT29 ATF2-KO cells upon 5-FU exposure with low p-Chk1Ser317 levels, strong apoptosis induction, but no effects on DNA damage. In ATF2-silenced HCT116 p53-/- cells, 5-FU did not activate the DDR pathway. Co-immunoprecipitation and proximity ligation assays revealed that upon 5-FU treatment, ATF2 binds to ATR to prevent Chk1 phosphorylation. Indeed, in silico modelling showed reduced ATR-Chk1 binding when ATF2 was docked into the complex. CONCLUSIONS: We demonstrated a novel ATF2 scaffold function involved in the DDR pathway. ATF2-negative cells are highly resistant due to effective ATR/Chk1 DNA damage repair. Mutant p53 seems to overwrite the tumor suppressor function of ATF2.
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Neoplasias do Colo , Proteína Supressora de Tumor p53 , Humanos , Proteína Supressora de Tumor p53/genética , Proteína Supressora de Tumor p53/metabolismo , Quinase 1 do Ponto de Checagem/genética , Quinase 1 do Ponto de Checagem/metabolismo , Proteínas Mutadas de Ataxia Telangiectasia/genética , Proteínas Mutadas de Ataxia Telangiectasia/metabolismo , Neoplasias do Colo/tratamento farmacológico , Neoplasias do Colo/genética , Fluoruracila/farmacologia , Dano ao DNA , Fator 2 Ativador da Transcrição/genéticaRESUMO
In cancer, the activating transcription factor 2 (ATF2) has pleiotropic functions in cellular responses to growth stimuli, damage, or inflammation. Due to only limited studies, the significance of ATF2 in colorectal cancer (CRC) is not well understood. We report that low ATF2 levels correlated with worse prognosis and tumor aggressiveness in CRC patients. NanoString gene expression and ChIP analysis confirmed trophoblast cell surface antigen 2 (TROP2) as a novel inhibitory ATF2 target gene. This inverse correlation was further observed in primary human tumor tissues. Immunostainings revealed that high intratumoral heterogeneity for ATF2 and TROP2 expression was sustained also in liver metastasis. Mechanistically, our in vitro data of CRISPR/Cas9-generated ATF2 knockout (KO) clones revealed that high TROP2 levels were critical for cell de-adhesion and increased cell migration without triggering EMT. TROP2 was enriched in filopodia and displaced Paxillin from adherens junctions. In vivo imaging, micro-computer tomography, and immunostainings verified that an ATF2KO/TROP2high status triggered tumor invasiveness in in vivo mouse and chicken xenograft models. In silico analysis provided direct support that ATF2low/TROP2high expression status defined high-risk CRC patients. Finally, our data demonstrate that ATF2 acts as a tumor suppressor by inhibiting the cancer driver TROP2. Therapeutic TROP2 targeting might prevent particularly the first steps in metastasis, i.e., the de-adhesion and invasion of colon cancer cells.
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Fator 2 Ativador da Transcrição , Antígenos de Neoplasias , Neoplasias Colorretais , Fator 2 Ativador da Transcrição/genética , Fator 2 Ativador da Transcrição/metabolismo , Animais , Antígenos de Neoplasias/genética , Antígenos de Neoplasias/metabolismo , Moléculas de Adesão Celular/genética , Moléculas de Adesão Celular/metabolismo , Linhagem Celular Tumoral/metabolismo , Proliferação de Células , Neoplasias Colorretais/genética , Neoplasias Colorretais/patologia , Humanos , Camundongos , Regulação para CimaRESUMO
Oncolytic viruses (OVs) are promising therapeutics for tumors with a poor prognosis. An OV based on herpes simplex virus type 1 (oHSV-1), talimogene laherparepvec (T-VEC), has been recently approved by the Food and Drug Administration (FDA) and by the European Medicines Agency (EMA) for the treatment of unresectable melanoma. T-VEC, like most OVs, is administered via intratumoral injection, underlining the unresolved problem of the systemic delivery of the oncolytic agent for the treatment of metastases and deep-seated tumors. To address this drawback, cells with a tropism for tumors can be loaded ex vivo with OVs and used as carriers for systemic oncolytic virotherapy. Here, we evaluated human monocytes as carrier cells for a prototype oHSV-1 with a similar genetic backbone as T-VEC. Many tumors specifically recruit monocytes from the bloodstream, and autologous monocytes can be obtained from peripheral blood. We demonstrate here that oHSV-1-loaded primary human monocytes migrated in vitro towards epithelial cancer cells of different origin. Moreover, human monocytic leukemia cells selectively delivered oHSV-1 to human head-and-neck xenograft tumors grown on the chorioallantoic membrane (CAM) of fertilized chicken eggs after intravascular injection. Thus, our work shows that monocytes are promising carriers for the delivery of oHSV-1s in vivo, deserving further investigation in animal models.
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Herpesvirus Humano 1 , Melanoma , Terapia Viral Oncolítica , Vírus Oncolíticos , Embrião de Galinha , Animais , Humanos , Herpesvirus Humano 1/genética , Melanoma/terapia , Galinhas , Monócitos , Membrana Corioalantoide , Vírus Oncolíticos/genéticaRESUMO
Exosomes are extracellular vesicles that modulate essential physiological and pathological signals. Communication between cancer cells that express the von Hippel-Lindau (VHL) tumor suppressor gene and those that do not is instrumental to distant metastasis in renal cell carcinoma (RCC). In a novel metastasis model, VHL(-) cancer cells are the metastatic driver, while VHL(+) cells receive metastatic signals from VHL(-) cells and undergo aggressive transformation. This study investigates whether exosomes could be mediating metastatic crosstalk. Exosomes isolated from paired VHL(+) and VHL(-) cancer cell lines were assessed for physical, biochemical, and biological characteristics. Compared to the VHL(+) cells, VHL(-) cells produce significantly more exosomes that augment epithelial-to-mesenchymal transition (EMT) and migration of VHL(+) cells. Using a Cre-loxP exosome reporter system, the fluorescent color conversion and migration were correlated with dose-dependent delivery of VHL(-) exosomes. VHL(-) exosomes even induced a complete cascade of distant metastasis when added to VHL(+) tumor xenografts in a duck chorioallantoic membrane (dCAM) model, while VHL(+) exosomes did not. Therefore, this study supports that exosomes from VHL(-) cells could mediate critical cell-to-cell crosstalk to promote metastasis in RCC.
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Carcinoma de Células Renais , Exossomos , Neoplasias Renais , Humanos , Carcinoma de Células Renais/patologia , Neoplasias Renais/metabolismo , Exossomos/metabolismo , Proteína Supressora de Tumor Von Hippel-Lindau/genética , Proteína Supressora de Tumor Von Hippel-Lindau/metabolismoRESUMO
In this study, pyruvate dehydrogenase kinase-1 inhibition with dichloroacetate (DCA) was explored as an alternative cancer therapy. The study's aim was to compare the effectiveness of NaDCA and MgDCA on pediatric glioblastoma PBT24 and SF8628 tumors and cells. The treatment effects were evaluated on xenografts growth on a chicken embryo chorioallantoic membrane. The PCNA, EZH2, p53, survivin expression in tumor, and the SLC12A2, SLC12A5, SLC5A8, CDH1, and CDH2 expression in cells were studied. The tumor groups were: control, cells treated with 10 mM and 5 mM of NaDCA, and 5 mM and 2.5 mM of MgDCA. The cells were also treated with 3 mM DCA. Both the 10 mM DCA preparations significantly reduced PBT24 and SF8624 tumor invasion rates, while 5 mM NaDCA reduced it only in the SF8628 tumors. The 5 mM MgDCA inhibited tumor-associated neoangiogenesis in PBT24; both doses of NaDCA inhibited tumor-associated neoangiogenesis in SF8628. The 10 mM DCA inhibited the expression of markers tested in PBT24 and SF8628 tumors, but the 5 mM DCA affect on their expression depended on the cation. The DCA treatment did not affect the SLC12A2, SLC12A5, and SLC5A8 expression in cells but increased CDH1 expression in SF8628. The tumor response to DCA at different doses indicated that a contrast between NaDCA and MgDCA effectiveness reflects the differences in the tested cells' biologies.
Assuntos
Glioblastoma , Acetatos/uso terapêutico , Animais , Embrião de Galinha , Galinhas/metabolismo , Membrana Corioalantoide/metabolismo , Ácido Dicloroacético/farmacologia , Glioblastoma/metabolismo , Humanos , Magnésio/metabolismo , Transportadores de Ácidos Monocarboxílicos , Antígeno Nuclear de Célula em Proliferação/metabolismo , Piruvato Desidrogenase Quinase de Transferência de Acetil , Sódio/metabolismo , Membro 2 da Família 12 de Carreador de Soluto , Survivina/metabolismo , Proteína Supressora de Tumor p53RESUMO
BACKGROUND: The oncogenic PIM kinases and the tumor-suppressive LKB1 kinase have both been implicated in the regulation of cell growth and metabolism, albeit in opposite directions. Here we investigated whether these kinases interact with each other to influence AMPK activation and tumorigenic growth of prostate and breast cancer cells. METHODS: We first determined how PIM and LKB1 kinases affect AMPK phosphorylation levels. We then used in vitro kinase assays to demonstrate that LKB1 is phosphorylated by PIM kinases, and site-directed mutagenesis to identify the PIM target sites in LKB1. The cellular functions of PIM and LKB1 kinases were evaluated using either pan-PIM inhibitors or CRISPR/Cas9 genomic editing, with which all three PIM family members and/or LKB1 were knocked out from PC3 prostate and MCF7 breast cancer cell lines. In addition to cell proliferation assays, we examined the effects of PIM and/or LKB1 loss on tumor growth using the chick embryo chorioallantoic membrane (CAM) xenograft model. RESULTS: We provide both genetic and pharmacological evidence to demonstrate that inhibition of PIM expression or activity increases phosphorylation of AMPK at Thr172 in both PC3 and MCF7 cells, but not in their derivatives lacking LKB1. This is explained by our observation that all three PIM family kinases can phosphorylate LKB1 at Ser334. Wild-type LKB1, but not its phosphodeficient derivative, can restore PIM inhibitor-induced AMPK phosphorylation in LKB1 knock-out cells. In the CAM model, loss of LKB1 enhances tumorigenicity of PC3 xenografts, while cells lacking both LKB1 and PIMs exhibit slower proliferation rates and form smaller tumors. CONCLUSION: PIM kinases are novel negative regulators of LKB1 that affect AMPK activity in an LKB1-dependent fashion. The impairment of cell proliferation and tumor growth in cells lacking both LKB1 and PIMs indicates that these kinases possess a shared signaling role in the context of cancer. These data also suggest that PIM inhibitors may be a rational therapeutic option for LKB1-deficient tumors. Video Abstract.
Assuntos
Quinases Proteína-Quinases Ativadas por AMP/metabolismo , Proteínas Quinases Ativadas por AMP/metabolismo , Carcinogênese/metabolismo , Carcinogênese/patologia , Proteínas Proto-Oncogênicas c-pim-1/metabolismo , Proteínas Quinases Ativadas por AMP/antagonistas & inibidores , Linhagem Celular Tumoral , Proliferação de Células , Ativação Enzimática , Humanos , Fosforilação , Ligação Proteica , Especificidade por SubstratoRESUMO
In the last decade, the chicken chorioallantoic membrane (CAM) assay has been re-discovered in cancer research to study the molecular mechanisms of anti-cancer drug effects. Literature about the CAM assay as an alternative in vivo cancer xenograft model according to the 3R principles has exploded in the last 3 years. Following a summary of the basic knowledge about the chicken embryo, we compare advantages and disadvantages with the classical mouse xenograft model, exemplify established and innovative imaging techniques that are used in the CAM model, and give examples of its successful utilization for studying major hallmarks of cancer such as angiogenesis, proliferation, invasion, and metastasis.
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Membrana Corioalantoide , Preparações Farmacêuticas , Animais , Bioensaio , Embrião de Galinha , Galinhas , Camundongos , Neovascularização Patológica/tratamento farmacológicoRESUMO
Diosgenin, a natural product with steroidal structure, has a wide range of clinical applications in China. It also shows great potential in the treatment of blood clots and nerve damage. To enhance the bioavailability as well as efficacy of diosgenin, eighteen diosgenin-amino acid derivatives were designed and synthesized. The neuroprotective effects of these compounds were evaluated by SH-SY5Y cell line and the biosafety was evaluated by H9c2 cell line. The results displayed that part of the derivatives' activities (EC50 < 20 µM) were higher than positive control edaravone (EC50 = 21.60 ± 3.04 µM), among which, DG-15 (EC50 = 6.86 ± 0.69 µM) exhibited the best neuroprotection. Meanwhile, biosafety evaluation showed that DG-15 had no cytotoxicity on H9c2 cell lines. Interestingly, combined neuroprotective and cytotoxic results, part of the derivatives without their protecting group were superior to compounds with protecting group. Subsequently, Giemsa staining and DAPI (4',6-diamidino-2-phenylindole) staining indicated that DG-15 had a protective effect on damaged SH-SY5Y cells by reducing apoptosis. Moreover, DG-15 showed a higher role in promoting angiogenesis at high concentrations (4 mg/mL) on the chorioallantoic membrane model. This finding displayed that DG-15 had dual functions of neuroprotection and angiogenesis, which provided further insight into designing agent for the application in treatment of ischemic stroke.
Assuntos
Indutores da Angiogênese , Diosgenina , Desenho de Fármacos , Neovascularização Fisiológica/efeitos dos fármacos , Fármacos Neuroprotetores , Indutores da Angiogênese/síntese química , Indutores da Angiogênese/química , Indutores da Angiogênese/farmacologia , Animais , Isquemia Encefálica/tratamento farmacológico , Isquemia Encefálica/metabolismo , Isquemia Encefálica/patologia , Linhagem Celular , Embrião de Galinha , Diosgenina/análogos & derivados , Diosgenina/síntese química , Diosgenina/química , Diosgenina/farmacologia , Avaliação Pré-Clínica de Medicamentos , Humanos , Fármacos Neuroprotetores/síntese química , Fármacos Neuroprotetores/química , Fármacos Neuroprotetores/farmacologia , Acidente Vascular Cerebral/tratamento farmacológico , Acidente Vascular Cerebral/metabolismo , Acidente Vascular Cerebral/patologiaRESUMO
Two bifunctional ruthenium(II)-p-cymene complexes with perfluorinated side chains, attached via pyridine ligands, have been evaluated in a series of in vitro and in vivo assays. Their effects on human endothelial (ECRF24 and HUVEC) cells, noncancerous human embryonic kidney (HEK-293) cells, and various human tumor cells were investigated. The complex with the shorter chain, 1, inhibits the proliferation of the tumor cell lines and ECRF24, whereas 2 selectively inhibits ECRF24 and HUVEC proliferation. Neither inhibits the migration of ECRF24 cells whereas both compounds inhibit sprout formation in HUVEC cells. Using three preclinical models, i.e., vasculature formation in the chorioallantoic membrane (CAM) of the chicken embryo, human A2780 ovarian carcinoma tumors xenografted on the CAM, and human LS174T colorectal adenocarcinoma tumors grown in athymic mice, the angiostatic and anticancer activities of these two complexes were studied. Overall, 1 inhibited tumor growth predominantly through an anticancer effect whereas 2 inhibited tumor growth predominately via an antiangiogenic mechanism.
Assuntos
Inibidores da Angiogênese/farmacologia , Antineoplásicos/farmacologia , Neoplasias Colorretais/tratamento farmacológico , Monoterpenos/química , Compostos Organometálicos/farmacologia , Neoplasias Ovarianas/tratamento farmacológico , Rutênio/química , Inibidores da Angiogênese/química , Animais , Antineoplásicos/química , Apoptose/efeitos dos fármacos , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , Embrião de Galinha , Membrana Corioalantoide/efeitos dos fármacos , Membrana Corioalantoide/metabolismo , Neoplasias Colorretais/metabolismo , Neoplasias Colorretais/patologia , Cimenos , Ensaios de Seleção de Medicamentos Antitumorais , Endotélio Vascular/citologia , Endotélio Vascular/efeitos dos fármacos , Endotélio Vascular/metabolismo , Feminino , Células HEK293 , Humanos , Técnicas Imunoenzimáticas , Camundongos , Modelos Moleculares , Neovascularização Patológica/prevenção & controle , Compostos Organometálicos/química , Neoplasias Ovarianas/metabolismo , Neoplasias Ovarianas/patologia , Relação Estrutura-AtividadeRESUMO
Malignant pleural mesothelioma (MPM) is an aggressive cancer associated with asbestos exposure. MPM is often diagnosed late, at a point where limited treatment options are available, but early intervention could improve the chances of successful treatment for MPM patients. Biomarkers to detect MPM in at-risk individuals are needed to implement early diagnosis technologies. Volatile organic compounds (VOCs) have previously shown diagnostic potential as biomarkers when analysed in MPM patient breath. In this study, chorioallantoic membrane (CAM) xenografts of MPM cell lines were used as models of MPM tumour development for VOC biomarker discovery with the aim of generating targets for investigation in breath, biopsies or other complex matrices. VOC headspace analysis of biphasic or epithelioid MPM CAM xenografts was performed using solid-phase microextraction and gas chromatography-mass spectrometry. We successfully demonstrated the capture, analysis and separation of VOC signatures from CAM xenografts and controls. A panel of VOCs was identified that showed discrimination between MPM xenografts generated from biphasic and epithelioid cells and CAM controls. This is the first application of the CAM xenograft model for the discovery of VOC biomarkers associated with MPM histological subtypes. These findings support the potential utility of non-invasive VOC profiling from breath or headspace analysis of tissues for detection and monitoring of MPM.
Assuntos
Membrana Corioalantoide , Cromatografia Gasosa-Espectrometria de Massas , Neoplasias Pulmonares , Mesotelioma Maligno , Neoplasias Pleurais , Compostos Orgânicos Voláteis , Compostos Orgânicos Voláteis/análise , Animais , Humanos , Mesotelioma Maligno/patologia , Neoplasias Pleurais/patologia , Neoplasias Pulmonares/patologia , Neoplasias Pulmonares/metabolismo , Biomarcadores Tumorais/análise , Mesotelioma/patologia , Linhagem Celular Tumoral , Xenoenxertos , Testes Respiratórios/métodos , Microextração em Fase Sólida/métodosRESUMO
Cannabidiol (CBD) is the main non-psychotropic cannabinoid. It has attracted a great deal of interest in the treatment of several diseases such as inflammatory disorders and cancer. Despite its promising clinical interest, its administration is very challenging. In situ forming implants (ISFIs) could be a simple and cheap strategy to administer CBD while obtaining a prolonged effect with a single administration. This work aims to design, develop, and characterize for the first time ISFIs for the parenteral administration of CBD with potential application in cancer disease. Formulations made of PLGA-502, PLGA-502H, and PLA-202 in NMP or DMSO and PLA-203 in DMSO at a polymer concentration of 0.25 mg/µL and loaded with CBD at a drug: polymer ratio of 2.5:100 and 5:100 (w/w) were developed. The formulations prepared with NMP exhibited a faster drug release. CBD implants elaborated with PLGA-502 and DMSO with the highest CBD: polymer ratio showed the most suitable drug release for one month. This formulation was successfully formed in ovo onto the chorioallantoic chick membrane without exhibiting signs of toxicity and exhibited a superior antiangiogenic activity than CBD in solution administered at the same doses. Consequently, implants made of PLGA-502 and DMSO represent a promising strategy to effectively administer CBD subcutaneously as combination therapy in cancer disease.
Assuntos
Canabidiol , Liberação Controlada de Fármacos , Poliésteres , Copolímero de Ácido Poliláctico e Ácido Poliglicólico , Animais , Canabidiol/administração & dosagem , Canabidiol/química , Copolímero de Ácido Poliláctico e Ácido Poliglicólico/química , Poliésteres/química , Implantes de Medicamento , Embrião de Galinha , Membrana Corioalantoide/efeitos dos fármacos , Dimetil Sulfóxido/química , Dimetil Sulfóxido/administração & dosagem , Portadores de Fármacos/química , Células Endoteliais da Veia Umbilical Humana/efeitos dos fármacosRESUMO
Lung cancer, one of the most common causes of high mortality worldwide, still lacks appropriate and convenient treatment options. Photodynamic therapy (PDT) has shown promising results against cancer, especially in recent years. However, pulmonary drug delivery of the predominantly hydrophobic photosensitizers still represents a significant obstacle. Nebulizing DPPC/Cholesterol liposomes loaded with the photosensitizer curcumin via a vibrating mesh nebulizer might overcome current restrictions. In this study, the liposomes were prepared by conventional thin-film hydration and two other methods based on dual centrifugation. The liposomes' physicochemical properties were determined before and after nebulization, showing that liposomes do not undergo any changes. However, morphological characterization of the differently prepared liposomes revealed structural differences between the methods in terms of lamellarity. Internalization of curcumin in lung adenocarcinoma (A549) cells was visualized and quantified. The generation of reactive oxygen species because of the photoreaction was also proven. The photodynamic efficacy of the liposomal formulations was tested against A549 cells. They revealed different phototoxic responses at different radiant exposures. Furthermore, the photodynamic efficacy was investigated after nebulizing curcumin-loaded liposomes onto xenografted tumors on the CAM, followed by irradiation, and evaluated using positron emission tomography/computed tomography and histological analysis. A decrease in tumor metabolism could be observed. Based on the efficacy of curcumin-loaded liposomes in 2D and 3D models, liposomes, especially with prior film formation, can be considered a promising approach for PDT against lung cancer.
Assuntos
Curcumina , Neoplasias Pulmonares , Humanos , Lipossomos/uso terapêutico , Curcumina/farmacologia , Curcumina/uso terapêutico , Sistemas de Liberação de Medicamentos , Nebulizadores e Vaporizadores , Fármacos Fotossensibilizantes/uso terapêutico , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/patologiaRESUMO
The development of the vascular system is essential for embryonic development, including processes such as angiogenesis. Angiogenesis plays a critical role in many normal physiological and pathological processes. It is driven by a set of angiogenic proteins, including angiogenic growth factors, chemokines, and extracellular matrix proteins. Among various animal model systems, the chorioallantoic membrane (CAM), a specialized and highly vascularized tissue of the avian embryo, has proven to be a valuable tool for analyzing the angiogenic potential of candidate cells or factors. In this protocol, we provide detailed procedures for establishing the CAM model to evaluate the function and mechanism of migrasomes in embryonic angiogenesis. This includes the CAM nylon mesh assay and CAM ex vivo sprouting assay to assess CAM angiogenesis, as well as the observation, purification, and delivery of migrasomes. Additionally, we describe the generation of T4-KO-mCherry-KI embryos using the CRISPR system within the CAM tissue to investigate the role of migrasomes in angiogenesis.
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Mouse models are commonly used to study the biodistribution of novel radioligands, but alternative models corresponding to the 3Rs principles, such as the chorioallantoic membrane (CAM) model, are highly required. While there are promising data from the CAM model regarding target-specific radiolabeled compounds, its utility for assessing macromolecule biodistribution and analyzing the EPR effect remains to demonstrated. Using 89Zr-labeled human serum albumin, the accumulation of nontarget-specific macromolecules in CAM and mouse xenograft models was studied using PET and MRI. Therefore, the radioligand [89Zr]Zr-DFO-HSA was analyzed in both chicken embryos (n = 5) and SCID mice (n = 4), each with TZM-bl and PC-3 tumor entities. Dynamic PET and anatomical MRI, as well as ex vivo biodistribution analyses, were performed to assess ligand distribution over 24 h. Histological staining and autoradiography verified the intratumoral accumulation. The tumors were successfully visualized for CAM and mouse models by PET, and the albumin influx from the blood into the respective tumors did not differ significantly. The accumulation and retention of HSA in tumors due to the EPR effect was demonstrated for both models. These results highlight that the CAM model is a potential alternative to the mouse model for initial studies with novel radiolabeled macromolecules with respect to the 3Rs principles.
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The application of photodynamic therapy has become more and more important in combating cancer. However, the high lipophilic nature of most photosensitizers limits their parenteral administration and leads to aggregation in the biological environment. To resolve this problem and deliver a photoactive form, the natural photosensitizer parietin (PTN) was encapsulated in poly(lactic-co-glycolic acid) nanoparticles (PTN NPs) by emulsification diffusion method. PTN NPs displayed a size of 193.70 nm and 157.31 nm, characterized by dynamic light scattering and atomic force microscopy, respectively. As the photoactivity of parietin is essential for therapy, the quantum yield of PTN NPs and the in vitro release were assessed. The antiproliferative activity, the intracellular generation of reactive oxygen species, mitochondrial potential depolarization, and lysosomal membrane permeabilization were evaluated in triple-negative breast cancer cells (MDA-MB-231 cells). At the same time, confocal laser scanning microscopy (CLSM) and flow cytometry were used to investigate the cellular uptake profile. In addition, the chorioallantoic membrane (CAM) was employed to evaluate the antiangiogenic effect microscopically. The spherical monomodal PTN NPs show a quantum yield of 0.4. The biological assessment on MDA-MB-231 cells revealed that free PTN and PTN NPs inhibited cell proliferation with IC50 of 0.95 µM and 1.9 µM at 6 J/cm2, respectively, and this can be attributed to the intracellular uptake profile as proved by flow cytometry. Eventually, the CAM study illustrated that PTN NPs could reduce the number of angiogenic blood vessels and disrupt the vitality of xenografted tumors. In conclusion, PTN NPs are a promising anticancer strategy in vitro and might be a tool for fighting cancer in vivo.
Assuntos
Emodina , Nanopartículas , Neoplasias de Mama Triplo Negativas , Humanos , Neoplasias de Mama Triplo Negativas/tratamento farmacológico , Portadores de Fármacos , Fármacos Fotossensibilizantes/farmacologia , Linhagem Celular TumoralRESUMO
Natural photosensitizers, such as curcumin or parietin, play a vital role in photodynamic therapy (PDT), causing a light-mediated reaction that kills cancer cells. PDT is a promising treatment option for glioblastoma, especially when combined with nanoscale drug delivery systems. The curcumin- or parietin-loaded lipid nanoparticles were prepared via dual asymmetric centrifugation and subsequently characterized through physicochemical analyses including dynamic light scattering, laser Doppler velocimetry, and atomic force microscopy. The combination of PDT and lipid nanoparticles has been evaluated in vitro regarding uptake, safety, and efficacy. The extensive and well-vascularized chorioallantois membrane (CAM) of fertilized hen's eggs offers an optimal platform for three-dimensional cell culture, which has been used in this study to evaluate the photodynamic efficacy of lipid nanoparticles against glioblastoma cells. In contrast to other animal models, the CAM model lacks a mature immune system in an early stage, facilitating the growth of xenografts without rejection. Treatment of xenografted U87 glioblastoma cells on CAM was performed to assess the effects on tumor viability, growth, and angiogenesis. The xenografts and the surrounding blood vessels were targeted through topical application, and the effects of photodynamic therapy have been confirmed microscopically and via positron emission tomography and X-ray computed tomography. Finally, the excised xenografts embedded in the CAM were analyzed histologically by hematoxylin and eosin and KI67 staining.
Assuntos
Curcumina , Glioblastoma , Fotoquimioterapia , Humanos , Animais , Feminino , Fotoquimioterapia/métodos , Glioblastoma/tratamento farmacológico , Glioblastoma/patologia , Curcumina/farmacologia , Curcumina/uso terapêutico , Galinhas , Linhagem Celular TumoralRESUMO
Diagnosing Intracranial Hemorrhage (ICH) at an early stage is difficult since it affects the blood vessels in the brain, often resulting in death. We propose an ensemble of Convolutional Neural Networks (CNNs) combining Squeeze and Excitation-based Residual Networks with the next dimension (SE-ResNeXT) and Long Short-Term Memory (LSTM) Networks in order to address this issue. This research work primarily used data from the Radiological Society of North America (RSNA) brain CT hemorrhage challenge dataset and the CQ500 dataset. Preprocessing and data augmentation are performed using the windowing technique in the proposed work. The ICH is then classified using ensembled CNN techniques after being preprocessed, followed by feature extraction in an automatic manner. ICH is classified into the following five types: epidural, intraventricular, subarachnoid, intra-parenchymal, and subdural. A gradient-weighted Class Activation Mapping method (Grad-CAM) is used for identifying the region of interest in an ICH image. A number of performance measures are used to compare the experimental results with various state-of-the-art algorithms. By achieving 99.79% accuracy with an F-score of 0.97, the proposed model proved its efficacy in detecting ICH compared to other deep learning models. The proposed ensembled model can classify epidural, intraventricular, subarachnoid, intra-parenchymal, and subdural hemorrhages with an accuracy of 99.89%, 99.65%, 98%, 99.75%, and 99.88%. Simulation results indicate that the suggested approach can categorize a variety of intracranial bleeding types. By implementing the ensemble deep learning technique using the SE-ResNeXT and LSTM models, we achieved significant classification accuracy and AUC scores.
RESUMO
The chorioallantoic membrane (CAM) assay is an increasingly popular method using a hen's egg as an experimental organism. Animal models have been established in scientific research for centuries. Yet, awareness of animal welfare in society rises, and the transferability of findings obtained in rodent models to human physiology is challenged. Thus, using fertilized eggs as an alternative platform for animal experimentation might be a promising alternative. The CAM assay is utilized for toxicological analysis by determination of CAM irritation as well as analysis of organ damage and ultimately death of the embryo. Furthermore the CAM provides a micromilieu suited for the implantation of xenografts. Xenogene tissues and tumors grow on the CAM due to a lack of rejection by the immune system and a dense vascular network providing oxygen and nutrients. Multiple analytical methods including in vivo microscopy and various imaging techniques are applicable to this model. Additionally, ethical aspects, a comparatively low financial burden, and low bureaucratic hurdles legitimize the CAM assay.We here describe an in ovo model utilized for xenotransplantation of a human tumor. The model can be used to evaluate the efficacy as well as the toxicity of different therapeutic agents after intravascular injection. Additionally, we present the evaluation of vascularization and viability by intravital microscopy, ultrasonography, and immunohistochemistry.