Characterization and bioactivity of self-assembled anti-angiogenic chondroitin sulfate-ES2-AF nanoparticle conjugate

Xing, Liang; Sun, Feng; Wang, Zhendong; Li, Yan; Yang, Zhifang; Wang, Fengshan; Zhai, Guangxi; Tan, Haining

Chondroitin sulfate (CS) is a glycosaminoglycan composed of alternating d-glucuronic acid and N-acetyl-d-galactosamine residues and is widely present in the extracellular matrix and the cell surface of animal tissues, particularly in abundance in cartilage tissue. 1, 2 It is an endogenous mucopolysaccharide with good histocompatibility, which is often used for drug modification and the construction of drug carriers. CS-modified cisplatin displayed improved anti-cancer activity and reduced drug toxicity. 3 CS-modified glucocorticoids can prolong the release time of the drug in vivo and enhance the efficacy, without toxicity or side effects. 4 In addition, CS is also a ligand of CD44, which can specifically target the CD44-overexpressed tumor cells. [5] [6] [7] [8] A short peptide, ES2, containing eleven amino acids (IVRRADRAAVP) is the main active fragment of endostatin (ES), which has anti-angiogenic properties. We have studied the bioactivity of ES2 and found that it could effectively inhibit the proliferation and migration of endothelial cells. 9 A VEGFR1-selective hexapeptide (GNQWFI, AF) was 15-mL centrifuge tubes were purchased from Corning INC (New York, NY, USA). Dimethyl sulphoxide (DMSO) and tetrabutylammonium hydroxide (TBA) were purchased from Sinopharm Chemical Reagent Co., Ltd. (Shanghai, China). (Benzotriazol-1-yloxy)tris(dimethylamino)phosphonium hexafluorophosphate (BOP) was purchased from TCI Co., Ltd. (Shanghai, China). Fluorescein isothiocyanate (FITC) was purchased from Shanghai Purple One Reagent Factory (Shanghai, China). VEGF 165 and basic fibroblast growth factor (bFGF) were purchased from Peprotech (Rocky Hill, NJ, USA). Tween 20 and 3,3',5,5'-Tetramethylbenzidine color liquid were purchased from Beyotime Biological Technology Co., Ltd. (Shanghai, China). Anti-human IgG-HRP-Fc was purchased from Cusabio Biological Engineering Co., Ltd. (Wuhan, China). Recombinant CD44 protein and Flt-Fc were purchased from R&D Systems (Minneapolis, MN, USA). All other chemicals and reagents were of the highest commercial grade available.