Preparation Of HGRN A And Its Study Of Antitumor Activity In Vitro

In modern society,due to environmental pollution,social pressure and other issues,the incidence of tumors is getting higher and higher,and this problem has been gradually gained people's attention.There are many common methods for treating tumors,such as surgical resection,radiotherapy,and chemotherapy,etc.However,most of these common therapies have different side effects,which deteriorate the patient's constitution,greatly reduce the quality of life of the patient,and has great limitations.Compared with these common therapies,the methods of drug treatment and biological treatment have the advantages of small toxic side effects and low treatment costs.There are already protein drugs derived from the human body,which have been successfully applied clinically in the treatment of cancer.Based on research in this field,our team found that human granulin A(hGRN A)has antitumor activity.The greatest advantage of the anti-tumor active polypeptide is that it has high activity,small relative molecular mass,easy absorption by multiple channels,small adverse reactions,and low resistance to drug resistance.Therefore,research and mining of anti-tumor biologically active peptides will make significant progress in basic tumor research and clinical applications.The granule protein is the epithelin.The GRN family contains multiple cysteine residues and they all have a variety of functions.What the GRN family has in common is that all proteins contain 12 cysteine residues and These cysteine residues are arranged in highly conserved positions.The disulfide bonds formed by these cysteine residues constitute complex features.Human granule protein A(hGRN A)is a secreted protein polypeptide which is stable to acid and heat by the action of granzyme protein precursor under the action of hydrolase,and its molecular weight is 6kD.The study found that hGRN A is widely and stably present in epithelial cells,and plays an indispensable role in immune,tumorigenesis,neurological function and defensive homeostasis in human tissues.This subject first constructed the yeast expression vector pGAPZ?A-GRN A.The hGRN A gene fragment was recombined into the yeast SMD1168 H genome as a template for DNA cloning,and the recombinant expression of hGRN A in the eukaryotic system of yeast SMD1168 H was achieved.The fermentation conditions are then optimized from the aspects of inoculum size,fermentation temperature,fermentation time and medium composition,so that the protein yield is improved.Then the recombinant hGRN A is isolated and pu rified.The recombinant anti-cancer activity of hGRN A was determined by MTT assay.Studies have confirmed that hGRN A can induce tumor cell apoptosis and has certain anti-tumor activity.In summary,human granulin A has an inhibitory effect on tumor cells and has obvious cytotoxicity.Therefore,human granulin A has more advantages than traditional anti-tumor therapy,and further development research may become a new type of anti-cancer drug.This topic provides a strong theoretical support for this discovery.