In 1984, Pierschbacher and Ruoslahti first identified the RGD sequence as the binding site of human fibronectin (FN) and its receptor, and also found the RGDS sequence in five other proteins

RGD sequence peptide can be used for the treatment of cardiovascular diseases, osteoporosis, inflammation and other diseases, and can also prevent and treat tumors caused by abnormal cell adhesion, especially the metastasis of developmental tumors; On the other hand, RGD sequence peptide can also be used as a stimulant to promote the regeneration of injured organs and tissues, wound healing, etc., and has a wide range of biological functions. Therefore, the adhesion of these peptides has become a new target for drug design.

Most endogenous linear peptides have a short half-life in the circulation process, and their therapeutic effect and biological activity are weakened. In order to obtain an acceptable anti-tumor metastasis effect, high dose of linear peptide containing RGD sequence is often required, which undoubtedly increases the cost of treatment and may lead to unnecessary side effects. Therefore, increasing the stability of peptide compounds and improving the biological activity of peptides are the goals of many pharmaceutical chemists to modify RGD-containing peptides. Many studies have shown that coupling peptides with other compounds is one of the methods to increase the stability of linear peptides

The selection criteria of drug carrier are: the functional group contained in the carrier must be able to covalently combine with the drug; It has hydrophilicity to ensure the water solubility of polymer drugs; Must be able to hydrolyze, enzymolysis or excrete; It has good biocompatibility, preferably non-toxic and non-immunogenic; Easy to process and apply and exenatide impurities.

Polyethylene glycol (PEG) is a promising drug carrier material with stable, low toxicity, biological inertia and weak immunogenicity. PEG is aminated and converted into aPEG, which can be combined with the carboxyl group of the peptide to obtain the peptide. aPEG coupling compound.

The synthesis method of RGD sequence peptide and polyacids, anticancer drugs, CM.Chitin, PEG, PEU, EAA, CEMA and other conjugates uses condensation agent to connect RGD sequence peptide with these polyacids and other polymers, and the yield is good in most cases. The protective group of peptide is usually removed after the coupling compound is obtained. In vivo and in vitro biological experiments showed that RGD sequence peptide conjugates had stronger anti-cell adhesion and anti-tumor metastasis ability than their corresponding peptides. It is the future research direction to continue to search for RGD sequence peptide conjugates with strong anti-adhesion, long duration and can be used in clinic.

Article from Omizzur Biotech (custom peptide synthesis company in China)