Chick Embryo Chorioallantoic Membrane Research Articles

Silk fibroin/chitosan/montmorillonite sponge dressing: Enhancing hemostasis, antimicrobial activity, and angiogenesis for advanced wound healing applications

Open wounds present a significant challenge in healthcare, requiring careful management to prevent infection and promote wound healing. Advanced wound dressings are critical need to enhance their hemostatic capabilities, antimicrobial properties, and ability to support angiogenesis and sustained moisture for optimal healing. This study introduces a flexible hemostatic dressing designed for open wounds, integrating chitosan (CS) for hemostasis and biocompatibility, silk fibroin (SF) for mechanical strength, and montmorillonite (MMT) for enhanced drug transport. The CSSF@MMT dressings showed promising mechanical strength and swift hemostasis. The CIP-loaded CSSF@MMT demonstrated sustained release for up to one week, exhibiting antibacterial properties against both Gram-positive and Gram-negative bacteria. In vitro cell migration assay demonstrated that erythropoietin-loaded CSSF@MMT dressings promoted the proliferation and migration of endothelial cells. Similarly, the chick embryo chorioallantoic membrane study indicated the same dressings exhibited a significant increase in vascular regeneration. This research suggests that the CSSF@MMT sponge dressing, incorporated with CIP and erythropoietin, holds promise in effectively halting bleeding, creating a protective environment, diminishing inflammation, and fostering wound tissue regeneration. This potential makes it a significant advancement in open wound care, potentially lowering the need for limb amputation and decreasing wound care burden worldwide.

Liver cancer in ovo models for preclinical testing.

Immunotherapies have significantly improved the prognosis of patients with advanced hepatocellular carcinoma (HCC), although more than 70% of patients still do not respond to this first-line treatment. Many new combination strategies are currently being explored, which drastically increases the need for preclinical models that would allow large-scale testing of new immunotherapies and their combinations. We developed several in ovo (in the egg) human liver cancer models, based on human tumor xenografts of different liver cancer cell lines on the chicken embryo's chorioallantoic membrane. We characterized the angiogenesis, as well as the collagen accumulation and tumor immune microenvironment, and tested atezolizumab (anti-PD-L1) plus bevacizumab (anti-VEGF) treatment. Our results show the involvement of chicken immune cells in tumor growth, reproducing a classical non-inflamed "cold" as well as inflamed "hot" tumor status, depending on the in ovo liver cancer model. The treatment by atezolizumab and bevacizumab was highly efficient in the "hot" tumor model PLC/PRF/5 in ovo with the reduction of tumor size by 76% (p ≤ .0001) compared with the control, whereas the efficacy was limited in the "cold" Hep3B in ovo tumor. The contribution of the anti-PD-L1 blockade to the anti-tumoral effect in the PLC/PRF/5 in ovo model was demonstrated by the efficacy of atezolizumab monotherapy (p = .0080, compared with the control). To conclude, our study provides a detailed characterization and rational arguments that could help to partially replace conventional laboratory animals with a more ethical model, suited to the current needs of preclinical research of new immunotherapies for liver cancer.

Chitosan-collagen biopolymer biofilm derived from cephalopod gladius; Evaluation of osteogenesis, angiogenesis and wound healing for tissue engineering application

Chitosan (Ch) and acid-soluble collagen (ASC) from Doryteuthis singhalensis gladius were isolated to test their osteogenic, angiogenic, and wound healing capabilities in male Wistar rats. The results of the study showed that the ASC yield was 18.58 %, the total protein content was 86.43 % ± 0.18 %, and the amino acid composition was as follows: glycine, 15.68 %; proline, 13.84 %. A, B, I, II, and III show FT-IR amide regional bands at 3392, 2959, 1652, 1471, and 1237 cm−1 respectively. The electrophoretic pattern of ASC validated its molecular weights of 105 kDa and 96 kDa. The 1H NMR spectra showed pure singles at 1.99 ppm, and the UV–Vis spectrum showed a particular absorbance between 238 and 220 nm. The DSC showed two endothermic peaks: one with an To value of 119.72 °C and TP of 126.28 °C, and the other with 147.42 °C and 148.47 °C. Initially, we fabricated Ch and ASC biofilms at an 8.5:1.5 ratio for tissue engineering applications. A cellular-level study demonstrated good biocompatibility and enhanced osteoblastic differentiation of collagen chitosan films (CChF). Additionally, the biofilm exhibited increased angiogenic potency, as observed in the chick embryo chorioallantoic membrane (CAM) assay. The experimental animal model demonstrated that in wound healing, the CChF treated rats (95.75 ± 2.28 %) had a greater decrease in the diameter of the wound than the control rats (22.25 ± 2.45 %), followed by the CF (collagen film) treated rats (63.25 ± 2.08 %) and ChF (chitosan film) (52.67 ± 1.58 %). Rats treated with CChF had 48.82 ± 1.25 mg/g of hydroxyproline in NFGT and 75.25 ± 1.56 mg/g of overall protein. The higher hydroxyproline levels in the CChF-treated groups corroborated these histopathological findings. These results imply that by promoting the development of scars, inflammation, and proliferation, CChF accelerates the healing process.

Chick Embryo Chorioallantoic Membrane as a Platform for Assessing the InVivo Efficacy of Chimeric Antigen Receptor T-cell Therapy in Solid Tumors.

The fertilized chicken egg chorioallantoic membrane (CAM), a highly vascularized membrane nourishing the developing embryo, also supports rapid growth of three-dimensional vascularized tumors from engrafted cells and tumor explants. Because murine xenograft models suffer limitations of time, cost, and scalability, we propose CAM tumors as a rapid, efficient screening tool for assessing anti-tumor efficacy of chimeric Ag receptor (CAR) T cells against solid tumors. We tested the efficacy of human epidermal growth factor receptor 2 (HER2)-specific CAR T cells against luminescent, HER2-expressing (FaDu, SCC-47) or HER2-negative (MDA-MB-468) CAM-engrafted tumors. Three days after tumor engraftment, HER2-specific CAR T cells were applied to tumors grown on the CAM. Four days post-CAR T cell treatment, HER2-expressing FaDu and SCC-47 tumors treated with CAR T showed reduced viable cancer cells as assessed by luciferase activity. This reduction in viable tumor cells was confirmed by histology, with lower Ki-67 staining observed in CAR T cell-treated tumors relative to T cell-treated controls. Persistence of CAR T in CAM and tumor tissue 4 days post-treatment was confirmed by CD3 staining. Altogether, our findings support further development of the chick CAM as an invivo system for rapid, scalable screening of CAR T cell efficacy against human solid tumors.

The Chick Chorioallantoic Membrane as a Xenograft Model for the Quantitative Analysis of Uveal Melanoma Metastasis in Multiple Organs.

Uveal melanoma (UM) is the most common intraocular tumor in adults, and nearly 50% of patients develop metastatic disease with a high mortality rate. Therefore, the development of relevant preclinical in vivo models that accurately recapitulate the metastatic cascade is crucial. We exploited the chick embryo chorioallantoic membrane (CAM) xenograft model to quantify both experimental and spontaneous metastasis by qPCR analysis. Our study found that the transplanted UM cells spread predominantly and early in the liver, reflecting the primary site of metastasis in patients. Visible signs of pigmented metastasis were observed in the eyes, liver, and distal CAM. Lung metastases occurred rarely and brain metastases progressed more slowly. However, UM cell types of different origins and genetic profiles caused an individual spectrum of organ metastases. Metastasis to multiple organs, including the liver, was often associated with risk factors such as high proliferation rate, hyperpigmentation, and epithelioid cell type. The severity of liver metastasis was related to the hepatic metastatic origin and chromosome 8 abnormalities rather than monosomy 3 and BAP1 deficiency. The presented CAM xenograft model may prove useful to study the metastatic potential of patients or to test individualized therapeutic options for metastasis in different organs.

Cancer cell extravasation requires iplectin-mediated delivery of MT1-MMP at invadopodia.

Invadopodia facilitate cancer cell extravasation, but the molecular mechanism whereby invadopodia-specific proteases such as MT1-MMP are called to invadopodia is unclear. Mass spectrometry and immunoprecipitation were used to identify interactors of MT1-MMP in metastatic breast cancer cells. After identification, siRNA and small molecule inhibitors were used to assess the effect these interactors had on cellular invasiveness. The chicken embryo chorioallantoic membrane (CAM) model was used to assess extravasation and invadopodia formation in vivo. In metastatic breast cancer cells, MT1-MMP was found to associate with plectin, a cytolinker and scaffolding protein. Complex formation between plectin and MT1-MMP launches invadopodia formation, a subtype we termed iplectin (i = invadopodial). iPlectin delivers MT1-MMP to invadopodia and is indispensable for regulating cell surface levels of the enzyme. Genetic depletion of plectin with siRNA reduced invadopodia formation and cell invasion in vitro. In vivo extravasation efficiency assays and intravital imaging revealed iplectin to be a key contributor to invadopodia ultrastructure and essential for extravasation. Pharmacologic inhibition of plectin using the small molecule Plecstatin-1 (PST-1) abrogated MT1-MMP delivery to invadopodia and extravasation efficiency. Anti-metastasis therapeutic approaches that target invadopodia are possible by disrupting interactions between MT1-MMP and iplectin. NCT04608357.

Enhanced vascularity in gelatin scaffolds via copper-doped magnesium–calcium silicates incorporation: In-vitro and ex-ovo insights

Addressing a critical challenge in current tissue-engineering practices, this study aims to enhance vascularization in 3D porous scaffolds by incorporating bioceramics laden with pro-angiogenic ions. Specifically, freeze-dried gelatin-based scaffolds were infused with sol-gel-derived powders of Cu-doped akermanite (Ca2MgSi2O7) and bredigite (Ca7MgSi4O16) at various concentrations (10, 20, and 30 wt%). The scaffolds were initially characterized for their structural integrity, biodegradability, swelling behavior, impact on physiological pH, and cytocompatibility with human umbilical vein endothelial cells (HUVECs). The silicate incorporation effectiveness in promoting vascularity was then assessed through HUVEC attachment, capillary tube formation, and ex-ovo chick embryo chorioallantoic membrane assays. The findings revealed significant improvements in both in-vitro and ex-ovo vascularity of the gelatin scaffolds upon the addition of Cu-doped akermanite. The most effective concentrations were determined to be 10 and 20 %, which led to notable HUVEC metabolic activity, a well-spread morphology with extensive peripheral filopodia and lamellipodia at 10 % and a cobblestone phenotype indicative of in-vivo endothelium at 20 % during cell attachment, the formation of complex networks of tubular structures, and robust vascularization in chick embryo development. Moving forward, the incorporation of Cu-doped akermanite into tissue-engineering scaffolds shows great potential for addressing the limitations of vascularization, especially for critical-sized bone defects, by facilitating the controlled release of pro-angiogenic and pro-osteogenic ions.

Design, synthesis, and evaluation of benzodioxolane compounds for antitumor activity

This study reports the design, synthesis, and comprehensive biological evaluation of 13 benzodioxolane derivatives, derived from the core structure of piperine, a natural product with established antitumor properties. Piperine, primarily found in black pepper, has been noted for its diverse pharmacological activities, including anti-inflammatory, antioxidant, and anticancer effects. Leveraging piperine’s antitumor potential, we aimed to enhance its efficacy through structural modifications. Among the synthesized compounds, HJ1 emerged as the most potent, exhibiting a 4-fold and 10-fold increase in inhibitory effects on HeLa and MDA-MB-231 cell lines, respectively, compared to piperine. Furthermore, HJ1 demonstrated a favorable safety profile, characterized by significantly lower cytotoxicity towards the human normal cell line 293T. Mechanistic investigations revealed that HJ1 markedly inhibited clonogenicity, migration, and adhesion of HeLa cells. In vivo studies utilizing the chick embryo chorioallantoic membrane (CAM) model substantiated the robust antitumor activity of HJ1, evidenced by its ability to suppress tumor angiogenesis and reduce tumor weight. These results suggest that HJ1 holds significant promise as a lead compound for the development of novel antitumor therapies.

Electrospun Gelatin Scaffolds with Incorporated Antibiotics for Skin Wound Healing.

Recent advances in regenerative medicine provide encouraging strategies to produce artificial skin substitutes. Gelatin scaffolds are successfully used as wound-dressing materials due to their superior properties, such as biocompatibility and the ability to mimic the extracellular matrix of the surrounding environment. In this study, five gelatin combination solutions were prepared and successfully electrospun using an electrospinning technique. After careful screening, the optimal concentration of the most promising combination was selected for further investigation. The obtained scaffolds were crosslinked with 25% glutaraldehyde vapor and characterized by scanning electron microscopy, energy-dispersive X-ray spectroscopy, and Fourier-transform infrared spectroscopy. The incorporation of antibiotic agents such as ciprofloxacin hydrochloride and gentamicin sulfate into gelatin membranes improved the already existing antibacterial properties of antibiotic-free gelatin scaffolds against Pseudomonas aeruginosa and Staphylococcus aureus. Also, the outcomes from the in vivo model study revealed that skin regeneration was significantly accelerated with gelatin/ciprofloxacin scaffold treatment. Moreover, the gelatin nanofibers were found to strongly promote the neoangiogenic process in the in vivo chick embryo chorioallantoic membrane assay. Finally, the combination of gelatin's extracellular matrix and antibacterial agents in the scaffold suggests its potential for effective wound-healing treatments, emphasizing the importance of gelatin scaffolds in tissue engineering.

The chick chorioallantoic membrane assay as an in vivo model for colon tumor analysis with optical coherence tomography

Optical coherence tomography (OCT) has emerged as a promising imaging modality for biomedical research. In this paper, a commercial OCT system was used to differentiate two colon cell lines implanted in a chick embryo chorioallantoic membrane (CAM) model, using the attenuation coefficient of light. Malignant and non-malignant tumors were developed from RKO and NCM460 cell lines, respectively. OCT B-scan images were collected from 30 CAM models, 15 with RKO-cells and 15 with NCM460-cells. A support vector machine (SVM) classifier was trained and tested using features obtained from two different bands of interest in the depth-resolved attenuation coefficient images. Quantitative analysis revealed that the non-malignant tumors present a higher attenuation coefficient than the malignant tumors immediately after the air-tissue interface. On the other side, at a depth of 206 µm, malignant tumors exhibit higher attenuation coefficient values. Using the features median, interquartile range, and maximum of the A-scans attenuation coefficient values for two adjacent bands in-depth, the SVM nested cross-validation presents an accuracy, recall, precision, and AUC of 1.0, which gives evidence that non-malignant and malignant tumors can be distinguished with high accuracy. This work represents an important step toward the use of OCT imaging for real-time biopsy of colorectal tissues.

Genistein-Aspirin Combination Exerts Cytotoxic and Anti-Migratory Effects in Human Colorectal Cancer Cells.

Colorectal cancer (CRC) is a heterogenous pathology with high incidence and mortality rates globally, but it is also preventable so finding the most promising candidates (natural compounds or repurposed drugs) to be chemopreventive alternatives has become a topic of interest in recent years. The present work aims to elucidate the potential effects of a combination between genistein (GEN), an isoflavone of natural origin, and aspirin (ASA) in CRC prevention/treatment by performing an in vitro evaluation in human colorectal cancer cells (HCT-116) and an in ovo analysis using the chick embryo chorioallantoic membrane (CAM) model. Cell viability was verified by an MTT (migratory potential by scratch) assay, and the expressions of MMP-2 and MMP-9 were analyzed using RT-qPCR. Our results indicated a dose-dependent cytotoxic effect of ASA (2.5 mM) + GEN (10-75 µM) combination characterized by reduced cell viability and morphological changes (actin skeleton reorganization and nuclei deterioration), an inhibition of HCT-116 cells' migratory potential by down-regulating MMP-2 and MMP-9 mRNA expressions, and an antiangiogenic effect by modifying the vascular network. These promising results raise the possibility of future in-depth investigations regarding the chemopreventive/therapeutical potential of ASA+GEN combination.

Phytochemical profiling, cytotoxic, anti-migration, and anti-angiogenic potential of phenolic-rich fraction from Peganum harmala: in vitro and in ovo studies.

Peganum harmala has been extensively employed in Algerian traditional medicine practices. This study aimed to explore the impact of n-butanol (n-BuOH) extract sourced from Peganum harmala seeds on cell proliferation, cell migration, and angiogenesis inhibition. Cytotoxic potential of n-BuOH extract was evaluated using MTT (3-(4,5-dimethylthiazol-2-yl) 2,5 diphenyltetrazolium bromide) assay against human breast adenocarcinoma MCF-7 cells, cell migration was determined using scratch assay, and anti-angiogenic effect was evaluated through macroscopic and histological examinations conducted on chick embryo chorioallantoic membrane. Additionally, this research estimated the phytochemical profile of n-BuOH extract. Fifteen phenolic compounds were identified using Ultra-performance liquid chromatography UPLC-ESI-MS-MS analysis. In addition, the n-BuOH extract of P. harmala exhibited potent antioxidant and free radical scavenging properties. The n-BuOH extract showed potent cytotoxicity against MCF-7 cell with an IC50 value of 8.68 ± 1.58 μg/mL. Furthermore, n-BuOH extract significantly reduced migration. A strong anti-angiogenic activity was observed in the groups treated with n-BuOH extract in comparison to the negative control. Histological analysis confirmed the anti-angiogenic effect of the n-BuOH extract. This activity is probably a result of the synergistic effects produced by different polyphenolic classes.

Glycosaminoglycans Modulate the Angiogenic Ability of Type I Collagen-Based Scaffolds by Acting on Vascular Network Remodeling and Maturation.

Type I collagen, prevalent in the extracellular matrix, is biocompatible and crucial for tissue engineering and wound healing, including angiogenesis and vascular maturation/stabilization as required processes of newly formed tissue constructs or regeneration. Sometimes, improper vascularization causes unexpected outcomes. Vascularization failure may be caused by extracellular matrix collagen and non-collagen components heterogeneously. This study compares the angiogenic potential of collagen type I-based scaffolds and collagen type I/glycosaminoglycans scaffolds by using the chick embryo chorioallantoic membrane (CAM) model and IKOSA digital image analysis. Two clinically used biomaterials, Xenoderm (containing type I collagen derived from decellularized porcine extracellular matrix) and a dual-layer collagen sponge (DLC, with a biphasic composition of type I collagen combined with glycosaminoglycans) were tested for their ability to induce new vascular network formation. The AI-based IKOSA app enhanced the research by calculating from stereomicroscopic images angiogenic parameters such as total vascular area, branching sites, vessel length, and vascular thickness. The study confirmed that Xenoderm caused a fast angiogenic response and substantial vascular growth, but was unable to mature the vascular network. DLC scaffold, in turn, produced a slower angiogenic response, but a more steady and organic vascular maturation and stabilization. This research can improve collagen-based knowledge by better assessing angiogenesis processes. DLC may be preferable to Xenoderm or other materials for functional neovascularization, according to the findings.

Effects of Resveratrol on In Vivo Ovarian Cancer Cells Implanted on the Chorioallantoic Membrane (CAM) of a Chicken Embryo Model.

Ovarian cancer poses a significant threat to patients in its advanced stages, often with limited treatment options available. In such cases, palliative management becomes the primary approach to maintaining a reasonable quality of life. Therefore, the administration of any medication that can benefit patients without a curative option holds potential. Resveratrol, a natural compound known for its in vitro anticancer activities, has generated contrasting results in vivo and human studies. In this study, we aimed to assess the anticancer effects of resveratrol on ovarian cancer cells grown on the chorioallantoic membrane (CAM) of chicken embryos. Two ovarian cancer cell lines, OVCAR-8 and SKOV-3, were cultured in collagen scaffolds for four days before being implanted on the CAM of chicken embryos on day 7. Different doses of resveratrol were applied to the CAM every two days for six days. Subsequently, CAM tissues were excised, fixed, and subjected to histological analysis. Some CAM tumours were extracted to analyse proteins through Western blotting. Our findings indicate that specific doses of resveratrol significantly reduce angiogenic activities, pNF-κB levels, and SLUG protein levels by using immunohistochemistry. These results suggest that resveratrol may have the potential to impact the behaviour of ovarian cancer CAM tumours, thereby warranting further consideration as a complementary treatment option for women with incurable ovarian cancer.

The biological characteristics of chicken embryo mesenchymal stem cells isolated from chorioallantoic membrane.

Mesenchymal stem cells (MSCs) derived from fetal membranes (FMs) have the potential to exhibit immunosuppression, improve blood flow, and increase capillary density during transplantation. In the field of medicine, opening up new avenues for disease treatment. Chicken embryo chorioallantoic membrane (CAM), as an important component of avian species FM structure, has become a stable tissue engineering material in vivo angiogenesis, drug delivery, and toxicology studies. Although it has been confirmed that chorionic mesenchymal stem cells (Ch-MSCs) can be isolated from the outer chorionic layer of FM, little is known about the biological characteristics of MSCs derived from chorionic mesodermal matrix of chicken embryos. Therefore, we evaluated the characteristics of MSCs isolated from chorionic tissues of chicken embryos, including cell proliferation ability, stem cell surface antigen, genetic stability, and in vitro differentiation potential. Ch-MSCs exhibited a broad spindle shaped appearance and could stably maintain diploid karyotype proliferation to passage 15 in vitro. Spindle cells were positive for multifunctional markers of MSCs (CD29, CD44, CD73, CD90, CD105, CD166, OCT4, and NANOG), while hematopoietic cell surface marker CD34, panleukocyte marker CD45, and epithelial cell marker CK19 were negative. In addition, chicken Ch-MSC was induced to differentiate into four types of mesodermal cells in vitro, including osteoblasts, chondrocytes, adipocytes, and myoblasts. Therefore, the differentiation potential of chicken Ch-MSC in vitro may have great potential in tissue engineering. In conclusion, chicken Ch-MSCs may be an excellent model cell for stem cell regenerative medicine and chorionic tissue engineering.

Abstract 1458: Anti tumoral role of PDX1 on pancreatic ductal adenocarcinoma aggressiveness

Abstract Pancreatic ductal adenocarcinoma (PDAC) represents a very aggressive type of pancreatic cancer (9% survival rate at 5 years). PDX1 is an important transcription factor for embryonic development of the pancreas, endocrine lineage differentiation and the maintenance of mature beta cells. Notably, in PDAC patients, the expression of PDX1 is downregulated in tumor cells compared to adjacent non-tumoral tissue. Interestingly, increasing tumor PDX1 expression has been shown to enhance the overall survival rate in PDAC patients. Therefore, our aim was to analyze the role of PDX1 on tumor aggressiveness of PDAC cells. To induce PDX1 expression, PANC1 cells were treated with BRD7552 (a PDX1 inducer) for 9 days. Overexpression of PDX1 was confirmed by Western Blot analysis and no cytotoxic effects were observed by MTT or Trypan Blue exclusion assays on treated cells compared to control. Wound healing and transwell migration assays showed a significant reduction in the migration rate compared to the control group. A higher proportion of cells in G1 phase was observed in treated cells compared to control by propidium iodide staining followed by flow cytometry assay. Furthermore, the cell confluence assay showed a significant reduction in proliferation rate in treated cells compared to control, but no differences were observed on the proportion of KI67+ and PH3+ cells by immunostaining. To assess the in ovo effects of BRD7552, treated PANC1 cells were implanted onto the chorioallantoic membrane of chick embryos and tumor growth was measured at different stages observing a significant reduction in tumor growth in PANC1 cells compared to control between days 3 and 8 post implantation. No significant differences in morphology or color were observed between treated and control implanted cells. Hematoxylin-eosin staining showed reduced invasion of treated cells into the chorioallantoic membrane compared to control. In conclusion, the overexpression of PDX1 affects cell cycle, reduces proliferation rate and inhibits migratory potential in vitro. Moreover, in an in ovo model this overexpression diminished tumor growth and invasion in PANC1 cells. In conclusion, the overexpression of PDX1 induced by BRD7552 drives pancreatic ductal adenocarcinoma to a less aggressive tumoral phenotype. Citation Format: Jimena Mosna, Federico Garde, Marcelo Stinson, Candela Pastore, Pablo Sanchis, Abel Carcagno. Anti tumoral role of PDX1 on pancreatic ductal adenocarcinoma aggressiveness [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 1458.

Alternating Current-Electric Field Inducing Chorio Allantoic Membrane (CAM) Angiogenesis through Exogenous Growth Factor Intervention

Angiogenesis is widely used in various therapies by promoting or inhibiting the formation of new blood vessels. The use of Alternating Current-Electric Fields (AC-EF) in Electro-Capacitive Cancer Therapy (ECCT) showed its potential as an anti-cancer device, and is characterized by its anti-proliferative and pro-apoptotic effects. However, the role of AC-EF in angiogenesis remains unclear. To investigate the effects of AC-EF on CAM angiogenesis, we used the ex ovo culture method of chorioallantoic membrane (CAM). A basic fibroblast growth factor (bFGF) dose of 30 ng/µL was administered as an exogenous growth factor. The ECCT device, generating AC-EF of 150 kHz and 18 Vpp, was exposed to the CAMs. Subsequently, the 24 CAMs of chick embryo were divided into four groups. Two groups were non-bFGF-induced CAM, while the other two were bFGF-induced CAM, and each group was exposed either with or without AC-EF. The vascularization was evaluated through macroscopic observation, while vascular endothelial growth factor A (VEGFA) gene expression was measured using qPCR. The data were statistically analyzed using ANOVA with GraphPad Prism 9.5. The results showed that an AC-EF exposure had no effects on normal CAM angiogenesis (P>0.05). Moreover, VEGFA gene expression did not show significant upregulation (P>0.05) in the bFGF-induced CAM with or without AC-EF exposure. Interestingly, the number of new blood vessels was significantly higher (P<0.05) in the bFGF-induced with AC-EF exposure than in the non-bFGF-induced group. In conclusion, AC-EF of ECCT did not affect normal angiogenesis. AC-EF may trigger CAM angiogenesis with bFGF induction. This observation suggested that AC-EF of intermediate frequency could enhance angiogenesis by administration of external growth factors, offering a potential avenue for addressing obstructive vascular conditions.

EPAC inhibitor suppresses angiogenesis and tumor growth of triple-negative breast cancer

AimsExchange protein directly activated by cAMP 1 (EPAC1), a major isoform of guanine nucleotide exchange factors, is highly expressed in vascular endothelia cells and regulates angiogenesis in the retina. High intratumor microvascular densities (MVD) resulting from angiogenesis is responsible for breast cancer development. Downregulation of EPAC1 in tumor cell reduces triple-negative breast cancer (TNBC)-induced angiogenesis. However, whether Epac1 expressed in vascular endothelial cells contributes to angiogenesis and tumor development of TNBC remains elusive. Main methodsWe employed NY0123, a previously identified potent EPAC inhibitor, to explore the anti-angiogenic biological role of EPAC1 in vitro and in vivo through vascular endothelial cells, rat aortic ring, Matrigel plug, and chick embryo chorioallantoic membrane (CAM) and yolk sac membrane (YSM) assays, as well as the in vivo xenograft tumor models of TNBC in both chick embryo and mice. Key findingsInhibiting EPAC1 in vascular endothelial cells by NY0123 significantly suppresses angiogenesis and tumor growth of TNBC. In addition, NY0123 possesses a better inhibitory efficacy than ESI-09, a reported specific EPAC inhibitor tool compound. Importantly, inhibiting EPAC1 in vascular endothelia cells regulates the typical angiogenic signaling network, which is associated with not only vascular endothelial growth factor (VEGF)/vascular endothelial growth factor receptor-2 (VEGFR2) signaling, but also PI3K/AKT, MEK/ERK and Notch pathway. ConclusionsOur findings support that EPAC1 may serve as an effective anti-angiogenic therapeutic target of TNBC, and EPAC inhibitor NY0123 has the therapeutic potential to be developed for the treatment of TNBC.

Inhibition of PRMT1 Suppresses the Growth of U87MG-Derived Glioblastoma Stem Cells by Blocking the STAT3 Signaling Pathway.

Glioblastoma stem cells (GSCs) play a pivotal role in the initiation, progression, resistance to treatment, and relapse of glioblastoma multiforme (GBM). Thus, identifying potential therapeutic targets and drugs that interfere with the growth of GSCs may contribute to improved treatment outcomes for GBM. In this study, we first demonstrated the functional role of protein arginine methyltransferase 1 (PRMT1) in GSC growth. Furamidine, a PRMT1 inhibitor, effectively inhibited the proliferation and tumorsphere formation of U87MG-derived GSCs by inducing cell cycle arrest at the G0/G1 phase and promoting the intrinsic apoptotic pathway. Moreover, furamidine potently suppressed the in vivo tumor growth of U87MG GSCs in a chick embryo chorioallantoic membrane model. In particular, the inhibitory effect of furamidine on U87MG GSC growth was associated with the downregulation of signal transducer and activator of transcription 3 (STAT3) and key GSC markers, including CD133, Sox2, Oct4, Nanog, aldehyde dehydrogenase 1, and integrin α6. Our results also showed that the knockdown of PRMT1 by small interfering RNA significantly inhibited the proliferation of U87MG GSCs in vitro and in vivo through a molecular mechanism similar to furamidine. In addition, combined treatment with furamidine and berbamine, a calcium/calmodulin-dependent protein kinase II gamma (CaMKIIγ) inhibitor, inhibited the growth of U87MG GSCs more strongly than single-compound treatment. The increased antiproliferative effect of combining the two compounds resulted from a stronger downregulation of STAT3-mediated downstream GBM stemness regulators through dual PRMT1 and CaMKIIγ function blockade. In conclusion, these findings suggest that PRMT1 and its inhibitor, furamidine, are potential novel therapeutic targets and drug candidates for effectively suppressing GSC growth.

Super-resolution ultrasound imaging with monodisperse microbubbles in a chicken embryo model

ULM is a super-resolution imaging method that has transformed ultrasound imaging by beating the diffraction limit, enabling the visualization of blood vessel down to the capillary size. The development of innovative ultrasound responsive agents may allow to further improve the performance of this technology. Bracco is engaged in the formulation and the evaluation of various ultrasound responsive agents for ULM including monodisperse microbubbles. Our recent studies have shown that monodisperse microbubbles increase imaging sensitivity by an order of magnitude in comparison to polydisperse microbubbles. The benefit of this for ultrasound localization microscopy (ULM) has been tested in vitro in flow phantom and in a chicken embryo chorio-allantoic membrane (CAM) model. The performances of the monodisperse versus polydisperse formulations were evaluated through a collection of numeric metrics extracted from the super-resolved reconstructed CAM images, including not only quantitative criteria, such as the number of detected microbubbles or the rate of successful tracking, but also geometrical considerations such as vessel density or number of segments of the reconstructed vasculature. The study showed that monodisperse formulations outperformed the other polydisperse formulations, particularly using low to moderate microbubble concentrations.