Chick Chorioallantoic Membrane Model Research Articles

Decellularized Bone Matrix/45S5 Bioactive Glass Biocomposite Hydrogel-Based Constructs with Angiogenic and Osteogenic Properties: Ex Ovo and Ex Vivo Evaluations.

Decellularized extracellular matrix is often used to create an in vivo-like environment that supports cell growth and proliferation, as it reflects the micro/macrostructure and molecular composition of tissues. On the other hand, bioactive glasses (BG) are surface-reactive glass-ceramics that can convert to hydroxyapatite in vivo and promote new bone formation. This study is designed to evaluate the key properties of a novel angiogenic and osteogenic biocomposite graft made of bovine decellularized bone matrix (DBM) hydrogel and 45S5 BG microparticles (10 and 20wt%) to combine the existing superior properties of both biomaterial classes. Morphological, physicochemical, mechanical, and thermal characterizations of DBM and DBM/BG composite hydrogels are performed. Their in vitro biocompatibility is confirmed by cytotoxicity and hemocompatibility analyses. Ex vivo chick embryo aortic arch and ex ovo chick chorioallantoic membrane (CAM) assays reveal that the present pro-angiogenic property of DBM hydrogels is enhanced by the incorporation of BG. Histochemical stainings (Alcian blue and Alizarin red) and digital image analysis of ossification on hind limbs of embryos used in the CAM model reveal the osteogenic potential of biomaterials. The findings support the notion that the developed DBM/BG composite hydrogel constructs have the potential to be a suitable graft for bone repair.

Facilitated Transport across Glycocalyceal Barriers in the Chick Chorioallantoic Membrane.

Targeted drug delivery to visceral organs offers the possibility of not only limiting the required dose, but also minimizing drug toxicity; however, there is no reliable method for delivering drugs to the surface of visceral organs. Here, we used six color tracers and the chick chorioallantoic membrane (CAM) model to investigate the use of the heteropolysaccharide pectin to facilitate tracer diffusion across the glycocalyceal charge barrier. The color tracers included brilliant blue, Congo red, crystal violet, indocyanine green, methylene blue, and methyl green. The direct application of the tracers to the CAM surface or embedding tracers into linear-chain nanocellulose fiber films resulted in no significant diffusion into the CAM. In contrast, when the tracers were actively loaded into branched-chain pectin films, there was significant detectable diffusion of the tracers into the CAM. The facilitated diffusion was observed in the three cationic tracers but was limited in the three anionic tracers. Diffusion appeared to be dependent on ionic charge, but independent of tracer size or molecular mass. We conclude that dye-loaded pectin films facilitated the diffusion of color tracers across the glycocalyceal charge barrier and may provide a therapeutic path for drug delivery to the surface of visceral organs.

A Multifunctional Scaffold for Bone Infection Treatment by Delivery of microRNA Therapeutics Combined With Antimicrobial Nanoparticles.

Treating bone infections and ensuring bone repair is one of the greatest global challenges of modern orthopedics, made complex by antimicrobial resistance (AMR) risks due to long-term antibiotic treatment and debilitating large bone defects following infected tissue removal. An ideal multi-faceted solution would will eradicate bacterial infection without long-term antibiotic use, simultaneously stimulating osteogenesis and angiogenesis. Here, a multifunctional collagen-based scaffold that addresses these needs by leveraging the potential of antibiotic-free antimicrobial nanoparticles (copper-doped bioactive glass, CuBG) to combat infection without contributing to AMR in conjunction with microRNA-based gene therapy (utilizing an inhibitor of microRNA-138) to stimulate both osteogenesis and angiogenesis, is developed. CuBG scaffolds reduce the attachment of gram-positive bacteria by over 80%, showcasing antimicrobial functionality. The antagomiR-138 nanoparticles induce osteogenesis of human mesenchymal stem cells in vitro and heal a large load-bearing defect in a rat femur when delivered on the scaffold. Combining both promising technologies results in a multifunctional antagomiR-138-activated CuBG scaffold inducing hMSC-mediated osteogenesis and stimulating vasculogenesis in an in vivo chick chorioallantoic membrane model. Overall, this multifunctional scaffold catalyzes killing mechanisms in bacteria while inducing bone repair through osteogenic and angiogenic coupling, making this platform a promising multi-functional strategy for treating and repairing complex bone infections.

Effects of Lactate Transport Inhibition by AZD3965 in Muscle-Invasive Urothelial Bladder Cancer.

The Warburg Effect is characterized by high rates of glucose uptake and lactate production. Monocarboxylate transporters (MCTs) are crucial to avoid cellular acidosis by internal lactate accumulation, being largely overexpressed by cancer cells and associated with cancer aggressiveness. The MCT1-specific inhibitor AZD3965 has shown encouraging results in different cancer models. However, it has not been tested in urothelial bladder cancer (UBC), a neoplasm where rates of recurrence, progression and platinum-based resistance are generally elevated. We used two muscle-invasive UBC cell lines to study AZD3965 activity regarding lactate production, UBC cells' viability and proliferation, cell cycle profile, and migration and invasion properties. An "in vivo" assay with the chick chorioallantoic membrane model was additionally performed, as well as the combination of the compound with cisplatin. AZD3965 demonstrated anticancer activity upon low levels of MCT4, while a general lack of sensitivity was observed under MCT4 high expression. Cell viability, proliferation and migration were reduced, cell cycle was arrested, and tumor growth "in vivo" was inhibited. The compound sensitized these MCT4-low-expressing cells to cisplatin. Thus, AZD3965 seems to display anticancer properties in UBC under a low MCT4-expression setting, but additional studies are necessary to confirm AZD3965 activity in this cancer model.

Composite of bacterial cellulose and gelatin: A versatile biocompatible scaffold for tissue engineering

Synthesis of 0.4 ± 0.03 g/L per day of pure and porous bacterial cellulose (BC) scaffolds (scaffBC) and BC scaffolds modified with gelatin (scaffBC/Gel) was carried out using the Medusomyces gisevii Sa-28 bacterial strain. FT-IR spectroscopy and X-ray diffraction analysis showed that the scaffolds largely consist of crystalline cellulose I (Iα, Iß). Heating of BC with gelatin to 60 °C with subsequent lyophilization led to its modification by adsorption and binding of low-molecular fractions of gelatin and the formation of small pores between the fibers, which increased the biocompatibility and solubility of BC. The solubility of scaffBC and scaffBC/Gel was 20.8 % and 44.4 %, respectively, which enhances degradation in vivo. Light microscopy, scanning electron microscopy, and microcomputed tomography showed a uniform distribution of pores with a diameter of 100–500 μm. The chicken chorioallantoic membrane (CAM) model and subcutaneous implantation in rats confirmed low immunogenicity and intense formation of collagen fibers in both scaffolds and active germination of new blood vessels in scaffBC and scaffBC/Gel. The proliferative cellular activity of fibroblasts confirmed the safety of scaffolds. Taken together, the results obtained show that scaffBC/Gel can be used for the engineering of hard and soft tissues, which opens opportunities for further research.

Effective seed cake extract of O. sanctum inducing the p53 dependent apoptotic pathway in oral cancer cells

Objective Present study was to observe the therapeutic aspects of seed cake extracts of Ocimum sanctum against the oral cancer cell line with the activation of p53 apoptotic pathway. Method Seed cake extracts were characterized using GC-MS analysis. Cytotoxic activity was observed on KB cells and L929 cell through MTT assay and scratch assay. Antioxidant activity on KB cells were determined using enzymatic and non enzyme content in the treated cells. Chick chorioallantoic membrane (CAM) was established to check the presence of blood vessel formation and neuvasculature pattern in the treated fertilized eggs. DNA fragmentation and gene expression studies were also determined in the treated cells to check the upregulation of apoptotic pathways. Results GC-MS analysis confirmed alkaloids, phenols, and many. The cytotoxic activity showed maximum antiproliferative potential with aqueous extract, whereas no cytotoxic effect was observed on L929 cells. The ethanolic and aqueous extract has shown a greater SI value. Scratch assay has signified that aqueous extract has a lower migration rate of KB cells. Aqueous extract showed maximum enzymatic activity and lower malondialdehyde content in cells treated with ethanolic extract. CAM model confirmed that eggs treated with aqueous extract has shown inhibition of vasculature pattern and dissolutions of blood vessels. DNA Fragmentation and Gene expression studies confirmed maximum fold in the KB cell treated with an aqueous extract of seed cake leading to activation of p53 dependent apoptotic pathway. Conclusion The potent therapeutic properties of seed cake extracts have been proven, and they can be used as herbal treatments to prevent oral cancer.

Exosomes modified with anti-MEK1 siRNA lead to an effective silencing of triple negative breast cancer cells

Triple negative breast cancer (TNBC) is a highly heterogenous disease not sensitive to endocrine or HER2 therapy and standardized treatment regimens are still missing. Therefore, development of novel TNBC treatment approaches is of utmost relevance. Herein, the potential of MAPK/ERK downregulation by RNAi-based therapeutics in a panel of mesenchymal stem-like TNBC cell lines was uncovered. Our data revealed that suppression of one of the central nodes of this signaling pathway, MEK1, affects proliferation, migration, and invasion of TNBC cells, that may be explained by the reversion of the epithelial-mesenchymal transition phenotype, which is facilitated by the MMP-2/MMP-9 downregulation. Moreover, an exosome-based system was successfully generated for the siRNA loading (iExoMEK1). Our data suggested absence of modification of the physical properties and general integrity of the iExoMEK1 comparatively to the unmodified counterparts. Such exosome-mediated downregulation of MEK1 led to a tumor regression accompanied by a decrease of angiogenesis using the chick chorioallantoic-membrane model. Our results highlight the potential of the targeting of MAPK/ERK cascade as a promising therapeutic approach against TNBC.

Feasibility of the chick chorioallantoic membrane model for preclinical studies on tumor radiofrequency ablation

BackgroundWe evaluated the feasibility of a chick chorioallantoic membrane (CAM) tumor model for preclinical research on tumor radiofrequency ablation (RFA).MethodsFertilized chicken eggs were incubated and divided into five cohorts: RFA for 30 s (n = 5), RFA for 60 s (n = 5), RFA for 120 s (n = 4), sham (n = 8), and controls (n = 6). Xenografting using pancreatic neuroendocrine tumor cells of the BON-1 cell line was performed on embryonic day (ED) 8. The RFA was performed on ED 12. Survival, stereomicroscopic observations, and histological observations using hematoxylin–eosin (H&E) and Ki67 staining were evaluated.ResultsThe survival rates in the 30-s, 60-s, and 120-s, sham and control cohort were 60%, 60%, 0%, 100%, and 50%, respectively. Signs of bleeding and heat damage were common findings in the evaluation of stereomicroscopic observations. Histological examination could be performed in all but one embryo. Heat damage, bleeding, thrombosis, and leukocyte infiltration and hyperemia were regular findings in H&E-stained cuts. A complete absence of Ki67 staining was recorded in 33.3% and 50% of embryos in the 30-s and 60-s cohorts that survived until ED 14, respectively.ConclusionsThe CAM model is a feasible and suiting research model for tumor RFA with many advantages over other animal models. It offers the opportunity to conduct in vivo research under standardized conditions. Further studies are needed to optimize this model for tumor ablations in order to explore promising but unrefined strategies like the combination of RFA and immunotherapy.Relevance statementThe chick chorioallantoic membrane model allows in vivo research on tumor radiofrequency ablation under standardized conditions that may enable enhanced understanding on combined therapies while ensuring animal welfare in concordance with the “Three Rs.”Key points• The chorioallantoic membrane model is feasible and suiting for tumor radiofrequency ablation.• Radiofrequency ablation regularly achieved reduction but not eradication of Ki67 staining.• Histological evaluation showed findings comparable to changes in humans after RFA.• The chorioallantoic membrane model can enable studies on combined therapies after optimization.Graphical

Hydroalcoholic Extract of Psoralea drupacea Inhibits Proliferation and Migration of Hepatocellular Carcinoma Cells and Decreases Angiogenesis in Chick Chorioallantoic Membrane

Objective: Hepatocellular carcinoma is one of the leading causes of cancer-related death worldwide. Experimental studies reported that some plants in the genus of Psoralea (Fabaceae family) show anticancer potential. The present study aimed to evaluate the effects of Psoralea drupacea extract (PDE) on HepG2 liver cancer cells. Methods: The proliferation, cell cycle, and migration of HepG2 cells were determined by thiazolyl blue tetrazolium bromide test, propidium iodide staining, and scratch assay, respectively. The effects of PDE on the activity of matrix metalloproteinases (MMPs) and angiogenesis were evaluated by the gelatin zymography method and chicken chorioallantoic membrane model, respectively. Results: The culture of HepG2 cells in the presence of PDE (24 hr and 48 hr) significantly reduced their viability (at a concentration of ≥ 50 µg/mL) and increased the percentage of cells in the sub-G1 stage. PDE also increased the antiproliferative and proapoptotic activities of doxorubicin (3 and 6 µg/mL). The extract significantly decreased the generation of reactive oxygen species and lipid peroxidation in the cells. Moreover, PDE (25 and 50 µg/mL) significantly suppressed the migration ability of HepG2 cells, which was associated with inhibition in the activity of MMP2 and MMP9 (50 µg/mL). Furthermore, treatment with PDE significantly reduced the number and diameter of vessels in the chick chorioallantoic membrane. Conclusion: PDE decreased the survival and cell cycle progression of liver cancer cells through a mechanism other than oxidative stress. This extract also showed an anti-angiogenesis effect and diminished the migration ability of HepG2 cells by inhibiting MMP activity

A MYCN-independent mechanism mediating secretome reprogramming and metastasis in MYCN-amplified neuroblastoma.

MYCN amplification (MNA) is a defining feature of high-risk neuroblastoma (NB) and predicts poor prognosis. However, whether genes within or in close proximity to the MYCN amplicon also contribute to MNA+ NB remains poorly understood. Here, we identify that GREB1, a transcription factor encoding gene neighboring the MYCN locus, is frequently coexpressed with MYCN and promotes cell survival in MNA+ NB. GREB1 controls gene expression independently of MYCN, among which we uncover myosin 1B (MYO1B) as being highly expressed in MNA+ NB and, using a chick chorioallantoic membrane (CAM) model, as a crucial regulator of invasion and metastasis. Global secretome and proteome profiling further delineates MYO1B in regulating secretome reprogramming in MNA+ NB cells, and the cytokine MIF as an important pro-invasive and pro-metastatic mediator of MYO1B activity. Together, we have identified a putative GREB1-MYO1B-MIF axis as an unconventional mechanism promoting aggressive behavior in MNA+ NB and independently of MYCN.

Novel biogenic silver nanoconjugates of Abrus precatorius seed extracts and their antiproliferative and antiangiogenic efficacies

Biogenic silver nanoconjugates (AgNCs), derived from medicinal plants, have been widely explored in the field of biomedicines. AgNCs for the first-time were synthesized using ethyl acetate seed extracts of Abrus precatorius and their antiproliferative and antiangiogenic efficacies were evaluated against cervical and oral carcinoma. Ultraviolet–Visible spectrophotometry, dynamic light Scattering (DLS), and scanning electron microscopy (SEM) were used for characterization of AgNCs. Antiproliferative activity was investigated using MTT, DNA fragmentation and in-vitro antioxidant enzyme activity assays. In-vivo chick chorioallantoic membrane (CAM) model was used to evaluate antiangiogenic activity. A total of 11 compounds were identified in both the extracts in GCMS analysis. The synthesized AgNCs were spherical shaped with an average size of 97.4 nm for AgAPE (Sox) and 64.3 nm for AgAPE (Mac). AgNCs possessed effective inhibition against Hep2C and KB cells. In Hep2C cells, AgAPE (Mac) revealed the highest SOD, catalase, GST activity and lower MDA content, whereas AgAPE (Sox) showed the highest GSH content. On the other hand, in KB cells, AgAPE (Sox) exhibited the higher SOD, GST activity, GSH content, and least MDA content, while AgAPE (Mac) displayed the highest levels of catalase activity. Docking analysis revealed maximum binding affinity of safrole and linoleic acid with selected targets. AgAPE (Sox), AgAPE (Mac) treatment profoundly reduced the thickness, branching, and sprouting of blood vessels in the chick embryos. This study indicates that A. precatorius-derived AgNCs have enhanced efficacies against cervical and oral carcinoma as well as against angiogenesis, potentially limiting tumour growth.

Dihydroartemisinin inhibits angiogenesis in breast cancer via regulating VEGF and MMP-2/-9.

Dihydroartemisinin (DHA) is an artemisinin derivative known for its antimalarial properties. It has also shown potential as an anti-tumor and anti-angiogenic agent. However, its specific role in inhibiting angiogenesis in breast cancer is not well understood. We aimed to investigate the anti-angiogenesis effect of DHA on breast cancer and explore its potential as a therapeutic drug. Our objectives were to assess the impact of DHA on neovascularization induced by MDA-MB-231 cells, evaluate its effects on vessel sprout and tube-formation in vascular endothelial cells, and analyze the expression of key angiogenesis-related proteins. Using a chicken chorioallantoic membrane (CAM) model, we cultured MDA-MB-231 cells and treated them with DHA. We assessed neovascularization and cultured vascular endothelial cells with DHA-treated cell media to evaluate vessel sprout and tube-formation. Protein expression levels of VEGF, MMP-2, and MMP-9 were analyzed using Western blotting. DHA significantly attenuated neovascularization induced by MDA-MB-231 cells. It also suppressed vessel sprout and tube-formation of HUVEC cells when exposed to DHA-treated cell media. Furthermore, DHA downregulated the expression of VEGF, MMP-2, and MMP-9 proteins. Mechanistically, DHA inhibited the phosphorylation of PI3K, AKT, ERK, and NF-κB proteins in tumor cells. Our study provides evidence of the inhibitory effect of DHA on breast cancer angiogenesis. These findings support the potential of DHA as an anti-breast cancer drug and warrant further investigation for its therapeutic applications.

The Chick Chorioallantoic Membrane (CAM) Model as a Tool to Study Ovarian Tissue Transplantation

Ovarian tissue cryopreservation and transplantation is an effective strategy for preserving fertility but has one major drawback, namely massive follicle loss occurring shortly after reimplantation due to abnormal follicle activation and death. Rodents are benchmark models for investigating follicle activation, but the cost, time, and ethical considerations are becoming increasingly prohibitive, thus driving the development of alternatives. The chick chorioallantoic membrane (CAM) model is particularly attractive, being inexpensive and maintaining natural immunodeficiency up to day 17 postfertilization, making it ideal to study short-term xenografting of human ovarian tissue. The CAM is also highly vascularized and has been widely used as a model to explore angiogenesis. This gives it a remarkable advantage over in vitro models and allows the investigation of mechanisms affecting the early post-grafting follicle loss process. The protocol outlined herein aims to describe the development of a CAM xenografting model for human ovarian tissue, with specific insights into the effectiveness of the technique, the graft revascularization time frame, and the tissue viability across a 6 day grafting period.

ATF2 loss promotes 5-FU resistance in colon cancer cells via activation of the ATR-Chk1 damage response pathway

BackgroundThe 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/ResultsFor our study, we had available HCT116 cells (wild-type p53) and HT29 colon tumor cells (mutant p53) and their corresponding CRISPR‒Cas9-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.ConclusionsWe 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.

The angiogenic potential of pH-neutral borophosphate bioactive glasses.

Borate bioactive glasses have gained attention in recent years due to their therapeutic and regenerative effects in vivo. However, borate bioactive glasses release alkaline ions, increasing the local pH and creating a toxic environment for cell culture studies. A partial compositional substitution of phosphate for borate can create a pH-neutral glass that does not significantly affect the local pH while still releasing therapeutic ions. In the present study, a series of Na-Ca-borophosphate bioactive glasses with different borate-to-phosphate ratios was evaluated in vitro and in vivo for cytotoxicity and angiogenic effects. Compared to more basic borate glasses, the pH-neutral glasses supported endothelial cell migration and stimulated greater blood vessel formation in a chick chorioallantoic membrane model. The results from this study indicate that these pH-neutral glasses are promising angiogenic biomaterials for use in tissue engineering and regenerative medicine.

Anti-angiogenic effect of nano-formulated water soluble kaempferol and combretastatin in an in vivo chick chorioallantoic membrane model and HUVEC cells

The present study evaluated the efficacy of nano-formulated water-soluble kaempferol and combretastatin alone and combined against the native kaempferol and combretastatin on angiogenesis. The solvent evaporation method was used to synthesize the nano-formulated water-soluble kaempferol and combretastatin and characterized using various analyses such as dynamic light scattering (DLS) and Fourier-transform infrared (FT-IR) spectroscopy.The anti-angiogenic activity of native, nano-formulated water-soluble kaempferol and combretastatin was investigated by cell viability on HUVEC and A498 cell lines, while chick chorioallantoic membrane (CAM) assay was utilized to assess morphometric and histopathological changes, and mRNA expressions of VEGF-A and FGF2 using qRT-PCR. MTT assay results revealed that the combination of nano-formulated water-soluble kaempferol and combretastatin significantly reduced the cell viability compared to control, individual treatments of native, nano-formulated water-soluble kaempferol, and combretastatin. Morphometric analysis of CAM showed that treatment with nano-formulated water-soluble kaempferol and combretastatin caused a substantial decrease in density, vessel network, branch points, and nets of CAM blood vessels. The histopathological results of CAM showed the irregular shape of blood vessels at the thin stratum of chronic endoderm, and blood capillaries were diminished compared to the control. In addition, the mRNA expression levels of VEGF-A and FGF2 were significantly decreased compared with native forms. Therefore, the findings of this study indicate that nano-formulated water-soluble combretastatin and kaempferol suppress angiogenesis by preventing the activation of endothelial cells and suppressing factors of angiogenesis. Moreover, a combination of nano-formulated water-soluble kaempferol and combretastatin worked much better than individual treatments.

Abstract 3620: N-myristoylation inhibition reduces angiogenesis and cancer cell migration

Abstract Myristoylation is the modification of proteins by the 14-carbon fatty acid myristate. In humans, two N-myristoyltransferases (NMT1 and NMT2) catalyze myristate transfer onto >200 proteins to regulate membrane binding and signal transduction. The pan-NMT inhibitor PCLX-001 has been in phase I clinical trials over a year for the treatment of lymphoma and advanced solid malignancies. Lack of myristoylation promotes the degradation of numerous normally myristoylated proteins like the proto-oncogenic Src family kinases (SFKs). SFKs like Src and Lyn are essential for downstream signaling of Vascular Endothelial Growth Factor (VEGF) and Epidermal Growth Factor (EGF) receptor tyrosine kinases. Thus, SFKs are critical for angiogenesis and cell motility. Angiogenesis is essential for tumor growth and dissemination of cancer cells to distal locations. VEGF-induced angiogenesis requires Src activation, suggesting that PCLX-001 may have antiangiogenic properties. SFKs also promote cell migration/metastasis, the leading cause of cancer-associated mortality. Lyn SFK knockdown was shown to reduce breast cancer migration and neighbouring tissue invasion, suggesting that PCLX-001 may also inhibit cell migration/metastasis. We investigated the antiangiogenic properties of PCLX-001 in vitro using HUVEC umbilical cord cells. PCLX-001 treatment significantly reduced HUVEC sprouting and tube-formation to levels lower than two FDA-approved angiogenesis inhibitors Sorafenib and Sunitinib. PCLX-001 also significantly reduced neo-vascularisation in vivo at lower concentrations than these two drugs using a chicken chorioallantoic membrane model, demonstrating the high potential of myristoylation inhibitors to reduce angiogenesis. We then validated our observations in vivo using a HT-1376 bladder mouse xenograft model. Tumors from mice treated for 28 days at increasing PCLX-001 concentrations showed significant reduction of Src, Lyn, and VEGF receptor protein levels as measured by immunohistochemistry, further validating PCLX-001 effect in vivo. We hypothesize that PCLX-001 acts downstream of VEGF/EGF receptors by inducing degradation of un-myristoylated SFKs. We confirmed this by knocking down NMT1 or treating breast cancer cells with PCLX-001 and found that both significantly reduced SFK protein levels. In a wound-healing assay using PCLX-001, we observed significant dose-dependent cell migration inhibition. PCLX-001 also dose-dependently reduced migration and invasion in transwell migration/invasion assays, indicating that myristoylation is required for optimal migration and potentially cancer cell metastasis. Overall, by lowering SFK levels, PCLX-001 reduces angiogenesis, cell migration/invasion, and thus potentially cancer metastasis. Reducing these classical cancer hallmarks in malignant cells may benefit a wide array of cancer patients and ultimately improve cancer treatment outcomes. Citation Format: Rony Pain, Erwan Beauchamp, Katia Carmine-Simmen, Jay Gamma, Rebecca Reif, Abul Azad, Allan Murray, John Lewis, Luc Berthiaume. N-myristoylation inhibition reduces angiogenesis and cancer cell migration. [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 3620.

Abstract 4866: Pharmacological mechanisms of osimertinib in advanced non-small lung cancer bearing the deletion exon 19 of EGFR In an original chicken chorioallantoic membrane (CAM) Model

Abstract Introduction: NSCLC accounts for about 80-85% of all lung cancers. Approximately 10-50% of patients with NSCLC harbor EGFR activating mutations, such as in-frame deletions in exon 19 (Ex19del). Currently, for patients with advanced NSCLC, testing for sensitizing mutations in EGFR is mandatory prior to the administration of anti-EGFR inhibitors such as Osimertinib. The CAM xenograft offers a rich environment in nutrients and embryonic growth factors, favorable for aggressive tumor development, with its highly vascularized membrane and natural immunodeficiency at engraftment (at EDD9). Methods: HCC827 Ex19del cells have been engrafted in ovo, and treated with various doses of osimertinib for seven days (4 treatments). The xenografts were collected and immunohistopathological, transcriptional and genetic analyses were carried out. Based on human transcriptional data, supervised multivariate discrimination between conditions and ontology analysis was performed through GSEA. Results: The xenograft growth was inversely dependent on the exposure dose of osimertinib, with a reduction in tumor weight of 58% for 10 µM (corresponding to 8.3 µg/Kg, T1/2 =4hr). The histological analysis showed epithelial tumor cells composed of solid sheets. The quantity of tumor cells was significantly lower in the treated group, with an area of tumor necrosis. The immunohistochemistry of tumor cells confirmed the human pulmonary epithelial origin, with TTF1 positive in treated and control groups. As expected, the ontology analysis of transcriptomic findings highlighted a downregulation of the EGFR pathway and its downstream effectors. Furthermore, the transcriptomic responses associated with chemotaxis, immune cell recruitment, and angiogenesis were dampened in the presence of osimertinib. This suggests that therapeutic efficacy was not uniquely guided through cell-autonomous mechanisms, but also takes place at the tissue level. We confirmed this in an independent experiment of in ovo HCC827 engraftment, showing a statically significant reduction of 15% in the number of vessels surrounding the xenograft in the osimertinib-treated condition. This demonstrates the advantage of using the in ovo model to decipher the regulations associated with therapeutics in a complex tissue context. Conclusions: For the first time, we have observed that osimertinib modulates angiogenesis and chemotaxis, which apparently reduces immune system recruitment and immune checkpoint responses. The ontologic analysis of transcriptomic findings in the CAM model strongly support the clinical observations of the pharmacological tumoral response to targeted therapy. The fact that immune infiltration was reduced in osimertinib-treated tumors may partially explain the lower response to immunotherapy regimens in osimertinib resistance contexts. Citation Format: David Barthelemy, Arnaud Vigneron, Xavier Rousset, Jerome Guitton, Emmanuel Grolleau, Margaux Raffin, Julie Balandier, Gaelle Lescuyer, Florence Geiguer, Sebastien Couraud, Jean Vaillet, Nazim Benzerdjeb, Lea Payen-Gay. Pharmacological mechanisms of osimertinib in advanced non-small lung cancer bearing the deletion exon 19 of EGFR In an original chicken chorioallantoic membrane (CAM) Model. [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 4866.

A Study of Ungernia trisphaera Bunge and Thymus transcaspicus Cytotoxicity in Cancer Cell Lines

Objective: Thymus transcaspicus (Lamiaceae) is an Iranian species of Thymus, and Ungernia trisphaera Bunge belongs to the family Amaryllidaceae. Cytotoxic properties of total ethanolic extract of T. transcaspicus and U. trisphaera were investigated against different cell lines including B16F10, PC3, U87, and MCF-7. Methods: The proliferation, cell cycle, and migration of the cells were determined by thiazolyl blue tetrazolium bromide (MTT) test, propidium iodide (PI) staining, and scratch assay respectively. The effects of U. trisphaera extract (UTE) on the activity of matrix metalloproteinases (MMPs) and angiogenesis were evaluated by the gelatin zymography method and chicken chorioallantoic membrane model, respectively. The GSH, SOD, and MDA were evaluated by colorimetric method. Results: The results showed that UTE could inhibit the development of malignant cells in a concentration- dependent manner, while the inhibitory effect of T. transcaspicus extract (TTE) was not significant compared to the control group. The UTE-induced sub-G1 peak apoptosis compared to the control group indicated that apoptotic cell death is involved in UTE-induced cytotoxicity. MMPs activity was significantly decreased 48 hours after treatment. Moreover, GSH level and SOD activity were significantly decreased while MDA and ROS levels were significantly increased after 24 hours treatment. In addition, combination of UTE (1.5-25 μg/mL) with doxorubicin (6 μg/mL) showed an additive cell growth inhibitory effect. Conclusion: UTE demonstrated cytotoxic and apoptogenic effects in different cancer cell lines, and it was found that apoptosis plays a crucial role in the cytotoxicity of UTE. Thus, U. trisphaera can be considered a potential medicinal herb in cancer treatment after comprehensive pharmacological and toxicological studies.

Chorioallantoic Membrane Assay at the Cross-Roads of Adipose-Tissue-Derived Stem Cell Research.

With a history of more than 100 years of different applications in various scientific fields, the chicken chorioallantoic membrane (CAM) assay has proven itself to be an exceptional scientific model that meets the requirements of the replacement, reduction, and refinement principle (3R principle). As one of three extraembryonic avian membranes, the CAM is responsible for fetal respiration, metabolism, and protection. The model provides a unique constellation of immunological, vascular, and extracellular properties while being affordable and reliable at the same time. It can be utilized for research purposes in cancer biology, angiogenesis, virology, and toxicology and has recently been used for biochemistry, pharmaceutical research, and stem cell biology. Stem cells and, in particular, mesenchymal stem cells derived from adipose tissue (ADSCs) are emerging subjects for novel therapeutic strategies in the fields of tissue regeneration and personalized medicine. Because of their easy accessibility, differentiation profile, immunomodulatory properties, and cytokine repertoire, ADSCs have already been established for different preclinical applications in the files mentioned above. In this review, we aim to highlight and identify some of the cross-sections for the potential utilization of the CAM model for ADSC studies with a focus on wound healing and tissue engineering, as well as oncological research, e.g., sarcomas. Hereby, the focus lies on the combination of existing evidence and experience of such intersections with a potential utilization of the CAM model for further research on ADSCs.