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Nanoprobes for Early Diagnosis of Cancer
Published in Klaus D. Sattler, st Century Nanoscience – A Handbook, 2020
Nanomaterials gadolinium oxide (Gd2O3), gadolinium fluoride (GdF3), and inorganic fluoride nanoparticles KGdF4 and NaGdF4 have been explored as promising T1 contrast agents for detection of cancer.15–18 For example, in a study performed by Hou and co-workers,19 they constructed differently sized NaGdF4-PEG-mAb nanoprobes with excellent binding specificity to epidermal growth factor receptor (EGFR). EGF and the aberrant activation of EGFR, such as overexpression of EGFR in tumor cells, play key roles in cell proliferation, cell motility, cell adhesion, invasion, cell survival, and angiogenesis, which result in the development and progression of various tumors. Thus, EGFR can work as a biomarker for early detection of tumor.20 NaGdF4 nanocrystals conjugated to anti-EGFR monoclonal antibody (mAb) via “click” reaction both on the maleimide residue on nanoparticle surface and on thiol group from the partly reduced anti-EGFR mAb. As shown in Figure 8.1, this probe exhibits excellent biocompatibility and presents superior contrast agent properties than GdDTPA (Magnevist). Moreover, NaGdF4-PEG-mAb probe displays promising tumor-specific targeting ability and enhanced MRI contrast effects.
Active Nanoparticle Targeting: Current Status and Future Challenges
Published in Sandeep Nema, John D. Ludwig, Parenteral Medications, 2019
Siddharth Patel, Janni Mirosevich
The way in which targeting moieties/ligands on nanoparticles can potentially adversely affect cell biology is another essential factor when evaluating targeted delivery systems. The melanocortin 1 receptor (MC1R) belongs to a family of five G protein-coupled melanocortin receptors (MC1R–MC5R) and is highly expressed on the surface of melanomas (Rosenkranz et al. 2013). As such, a number of highly specific and selective ligands against MC1R have been developed (Cai et al. 2006; Mayorov et al. 2006; Koikov et al. 2003). These ligands have been used for targeted imaging agents, targeted polymer-based micelles, and polymeric gene delivery nanoparticles (Durymanov et al. 2012; Barkey et al. 2011; Tafreshi et al. 2012; Barkey et al. 2013). However, MC1R activation is known to be involved in proliferation of melanoma cells (Rosenkranz et al. 2013). It is also known that EGF binding to EGFR activates signaling pathways that stimulate cell proliferation and survival (Master and Sen Gupta 2012; Wang 2012). Therefore, because many ligands are known to activate signaling pathways that promote cancer growth, downstream molecular pathways must be considered in order to ensure that nanoparticle ligand binding does not have unfavorable effects on the cells and tissues being treated.
Assessment of Quercetin Isolated from Enicostemma Littorale Against Few Cancer Targets: An in Silico Approach
Published in A. K. Haghi, Ana Cristina Faria Ribeiro, Lionello Pogliani, Devrim Balköse, Francisco Torrens, Omari V. Mukbaniani, Applied Chemistry and Chemical Engineering, 2017
Epidermal growth factor (EGF) is a growth factor that plays an important role in the regulation of cell growth, proliferation, and differentiation by binding to its receptor EGFR. Human EGF is a 6045-Da protein with 53 amino acid residues and three intramolecular disulfide bonds.5
Evaluation of a peptide motif designed for protein tethering to polymer surfaces
Published in Journal of Biomaterials Science, Polymer Edition, 2021
Ayana Nakano, Isao Hirata, Binh Vinh Pham, Ajay Shakya, Kotaro Tanimoto, Koichi Kato
EGF is known to be one of the growth factors and activates the tyrosine kinase EGF receptor to generate intracellular signals that have an impact on various cellular functions [27]. The experimental data on the phosphorylation of the tyrosine kinase receptor by, for example, western blotting, will be useful to gain insights into molecular mechanisms underlying cell responses mediated by tethered EGF. Previously it was demonstrated that surfaces tethering growth factors such as EGF [28,29] and bFGF [30,31] served to selectively entrap cells having the respective receptors. Initially entrapped cells weakly attach to the surface most likely through ligand-receptor interactions. This is followed by a gradual increase in adhesion forces, probably through the interaction of cell surface integrins with extracellular matrices secreted by the cells. The stability of the tethered EGF fusions during cell culture would have influences on the EGF-mediated cell attachment and signaling. Taking this into account, we tried to quantify the tethered EGF fusions remaining on the TCP and PCL surfaces after exposure to the culture medium for 7 d. However, we could not obtain reasonable results probably because of interference by proteinous constituents that might adsorb from the medium.
Epidermal stimulating factors-gelatin/polycaprolactone coaxial electrospun nanofiber: ideal nanoscale material for dermal substitute
Published in Journal of Biomaterials Science, Polymer Edition, 2021
Li Yan, Haoyu Wang, Hui Xu, Rui Zheng, Zhengyu Shen
Several mediators play a critical role in the different stages of healing. For example, epidermal growth factor (EGF) promotes healing in the wound area by stimulating the migration and proliferation of epithelial cells and fibroblasts [9]. Hydrocortisone (HC) and ascorbic-2-phosphoric (Asc-2-P) have the capacity to promote keratinocyte growth. Bone morphogenetic protein-4 (BMP-4) and all-trans retinoic acid (ATRA) guide epithelial differentiation of stem cells. Petry introduced a combination protocol of the five bio-reagents for trans-differentiation of mesenchymal stem cells into the epidermal cell line, which showed significant upregulation of cytokeratin expression on two-dimensional and three-dimensional culture discs [10]. Their findings demonstrated that a combination of bio-reagents associated with skin wound healing can prove beneficial for skin regeneration. Incorporating growth factors into electrospun nanofiber scaffolds can increase the bioactivity of scaffolds by supplying suitable chemical or biological cues and increasing cellularisation. Therefore, we encapsulated EGF, HC, Asc-2-P, BMP-4 and ATRA, which were defined as epidermal stimulating (ES) factors, into gelatin/polycaprolactone (GT/PCL) electrospun nanofibers using coaxial electrospinning strategy to obtain ES-GT/PCL (Supplementary material Figure S1). ES-GT/PCL can induce mesenchymal epidermal transformation (Supplementary material Figure S2).
A concise review on drug-loaded electrospun nanofibres as promising wound dressings
Published in Journal of Medical Engineering & Technology, 2019
Farzaneh Aavani, Sajedeh Khorshidi, Akbar Karkhaneh
Using growth factors has promising role in wound-healing process. Growth factors such as vascular endothelial growth factor (VEGF), platelet-derived growth factor (PDGF), transforming growth factor (TGF-β), epidermal growth factors (EGFs basic fibroblast growth factor (bFGF) and fibroblast growth factor (FGF-2) are presented at different healing stages with certain functionalities [57]. EGF plays an important role in the wound-healing process. For instance, this factor potentially can stimulate the proliferation and migration of keratinocytes. In addition, EGF can accelerate the wound healing by interaction with fibroblasts and keratinocytes superficial receptors. At first 5 days after injury, maximal differences are seen between EGF treated and untreated wounds, so this period of time is very critical in wound-healing process. EGF application after this period produces no significant improvement over controls, since by this time re-epithelialization has already occurred in both groups. The significant matter about EGF application in the case of wound dressing is its relatively short half-life of about 1 h. To conquer on this drawback, continually release of EFG in effective concentration during the critical period of initial wound healing is promising solution for effective local EGF delivery [58]. Another well-known growth factor is KFG or FGF-7. This bioactive molecule is expressed in mesenchymal origin cells and belongs to the fibroblast growth factor family. This monomeric peptide affects epithelial cells and is responsible for epidermal morphogenesis and wound healing. Under normal condition, KGF is present at very low levels in skin, whereas after injury is highly up-regulated [57].