scholarly journals Co-Culturing of Endothelial and Cancer Cells in a Nanofibrous Scaffold-Based Two-Layer System

2020 ◽  
Vol 21 (11) ◽  
pp. 4128
Author(s):  
Ye-Seul Oh ◽  
Min-Ho Choi ◽  
Jung-In Shin ◽  
Perry Ayn Mayson A. Maza ◽  
Jong-Young Kwak

Angiogenesis is critical for local tumor growth. This study aimed to develop a three-dimensional two-layer co-culture system to investigate effects of cancer cells on the growth of endothelial cells (ECs). Poly(ε-caprolactone) (PCL) nanofibrous membranes were generated via electrospinning of PCL in chloroform (C-PCL-M) and chloroform and dimethylformamide (C/DMF-PCL-M). We assembled a two-layer co-culture system using C-PCL-M and C/DMF-PCL-M for EC growth in the upper layer with co-cultured cancer cells in the lower layer. In the absence of vascular endothelial growth factor (VEGF), growth of bEND.3 ECs decreased on C/DMF-PCL-M but not on C-PCL-M with time. Growth of bEND.3 cells on C/DMF-PCL-M was enhanced through co-culturing of CT26 cancer cells and enhanced growth of bEND.3 cells was abrogated with anti-VEGF antibodies and sorafenib. However, EA.hy926 ECs displayed steady growth and proliferation on C/DMF-PCL-M, and their growth was not further increased through co-culturing of cancer cells. Moreover, chemical hypoxia in CT26 cancer cells upon treatment with CoCl2 enhanced the growth of co-cultured bEND.3 cells in the two-layer system. Thus, EC growth on the nanofibrous scaffold is dependent on the types of ECs and composition of nanofibers and this co-culture system can be used to analyze EC growth induced by cancer cells.

2020 ◽  
Vol 0 (0) ◽  
Author(s):  
Sinem Tunçer ◽  
Rafig Gurbanov

AbstractObjectivesThe expression level of Vascular Endothelial Growth Factor (VEGF) is assumed as a prognostic marker for several tumor types, including colorectal cancer. Therefore, the determination of pre- and post-therapy levels of VEGF appears to have great value in the assessment of tumor prognosis. Enzyme-Linked Immunosorbent Assay (ELISA) is commonly used for the determination of serum or plasma VEGF levels, but the method is costly and time-consuming. In this study, we aimed to describe a rapid and cost-effective analysis method to discriminate VEGF overexpressing colorectal cancer-derived conditioned medium (CM).MethodsAttenuated Total Reflection (ATR)-Fourier Transform Infrared (FTIR) spectroscopy, combined with Principal Component Analysis (PCA) and Linear Discriminant Analysis (LDA), was used to differentiate VEGF overexpressing colorectal cancer cell line CM from CM obtained from the corresponding control cells which express and secrete relatively lower amount of VEGF.ResultsSamples belong to VEGF overexpressing colorectal cancer cells were clearly distinguished from the control group with very high PC scores as PC1 + PC2 = 96%. Besides, a 100% accurate distinction between these two groups was achieved by the LDA analysis.ConclusionsATR-FTIR spectroscopy combined with pattern recognition techniques was able to discriminate CM of VEGF overexpressing colorectal cancer cells with high efficiency and accuracy.


2007 ◽  
Vol 293 (3) ◽  
pp. H1997-H2003 ◽  
Author(s):  
Xiang-Yang Zhu ◽  
Michael D. Bentley ◽  
Alejandro R. Chade ◽  
Erik L. Ritman ◽  
Amir Lerman ◽  
...  

Changes in the structure of the artery wall commence shortly after exposure to cardiovascular risk factors, such as hypercholesterolemia (HC), but may be difficult to detect. The ability to study vascular wall structure could be helpful in evaluation of the factors that instigate atherosclerosis and its pathomechanisms. The present study tested the hypothesis that early morphological changes in coronary arteries of hypercholesterolemic (HC) pigs can be detected using the novel X-ray contrast agent OsO4 and three-dimensional micro-computed tomography (CT). Two groups of pigs were studied after they were fed a normal or an HC (2% cholesterol) diet for 12 wk. Hearts were harvested, coronary arteries were injected with 1% OsO4 solution, and cardiac samples (6-μm-thick) were scanned by micro-CT. Layers of the epicardial coronary artery wall, early lesions, and perivascular OsO4 accumulation were determined. Leakage of OsO4 from myocardial microvessels was used to assess vascular permeability, which was correlated with immunoreactivity of vascular endothelial growth factor in corresponding histological cross sections. OsO4 enhanced the visualization of coronary artery wall layers and facilitated detection of early lesions in HC in longitudinal tomographic sections of vascular segments. Increased density of perivascular OsO4 in HC was correlated with increased vascular endothelial growth factor expression and suggested increased microvascular permeability. The use of OsO4 as a contrast agent in micro-CT allows three-dimensional visualization of coronary artery wall structure, early lesion formation, and changes in vascular permeability. Therefore, this technique can be a useful tool in atherosclerosis research.


2021 ◽  
Vol 108 (Supplement_6) ◽  
Author(s):  
Joshua Burke ◽  
Jack Helliwell ◽  
Mikolaj Kowal ◽  
David Jayne

Abstract Aim Platelet-rich fibrin (PRF) is a three-dimensional fibrin scaffold with associated platelets and leukocytes which releases high quantities of growth factors over a sustained period of time. PRF has shown promising clinical results in promoting wound healing and tissue regeneration. The aims of this feasibility study were to establish optimal spinning methods for production of PRF, to quantify the production of vascular endothelial growth factor (VEGF) by PRF and to explore new vehicles of clinical PRF delivery. Method Assessment of optimal production involved comparisons between Protocol 1 (EDTA bottle) and Protocol 2 (no additive) at three different centrifugation forces: 400g, 1000g and 1700g. VEGF production was analysed using ELISA with varied incubation periods and PRF plug segments. Novel methods for PRF delivery were explored using surgical sutures and a Zimmer® Skin Graft Mesher. Results Protocol 2 demonstrated shorter average time to blood draw (9.8s compared to 13.6s) and to centrifuge (25.5s compared to 33.1s) with a decreased range of values. All PRF segments exhibited a positive correlation between incubation time and amount of VEGF produced with the bottom segments producing on average more VEGF. A segment of the fibrin plug was successfully secured on a suture and meshed in a 1:1.5 ratio. Conclusions PRF production can be optimised using blood bottles with no additive and high centrifugation forces. VEGF production by PRF peaks at 120 hours with the bottom PRF segment exhibiting the highest rate of production. The first description of a PRF mesh enables new clinical applications.


2001 ◽  
Vol 21 (12) ◽  
pp. 3995-4004 ◽  
Author(s):  
Erik Laughner ◽  
Panthea Taghavi ◽  
Kelly Chiles ◽  
Patrick C. Mahon ◽  
Gregg L. Semenza

ABSTRACT Hypoxia-inducible factor 1 (HIF-1) is a transcriptional activator composed of HIF-1α and HIF-1β subunits. Several dozen HIF-1 targets are known, including the gene encoding vascular endothelial growth factor (VEGF). Under hypoxic conditions, HIF-1α expression increases as a result of decreased ubiquitination and degradation. The tumor suppressors VHL (von Hippel-Lindau protein) and p53 target HIF-1α for ubiquitination such that their inactivation in tumor cells increases the half-life of HIF-1α. Increased phosphatidylinositol 3-kinase (PI3K) and AKT or decreased PTEN activity in prostate cancer cells also increases HIF-1α expression by an undefined mechanism. In breast cancer, increased activity of the HER2 (also known as neu) receptor tyrosine kinase is associated with increased tumor grade, chemotherapy resistance, and decreased patient survival. HER2 has also been implicated as an inducer of VEGF expression. Here we demonstrate that HER2 signaling induced by overexpression in mouse 3T3 cells or heregulin stimulation of human MCF-7 breast cancer cells results in increased HIF-1α protein and VEGF mRNA expression that is dependent upon activity of PI3K, AKT (also known as protein kinase B), and the downstream kinase FRAP (FKBP-rapamycin-associated protein). In contrast to other inducers of HIF-1 expression, heregulin stimulation does not affect the half-life of HIF-1α but instead stimulates HIF-1α synthesis in a rapamycin-dependent manner. The 5′-untranslated region of HIF-1α mRNA directs heregulin-inducible expression of a heterologous protein. These data provide a molecular basis for VEGF induction and tumor angiogenesis by heregulin-HER2 signaling and establish a novel mechanism for the regulation of HIF-1α expression.


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