Aspargine-glycine-arginine (NGR)-containing peptides are targeted peptides which can be integrated with CD13 receptors on tumor vascular endothelial cells. NGR peptides are connected to liposomes to obtain NGR peptide-modified liposomes. By intravenous injection of these liposomes, NGR peptides can be combined with CD13 receptors on tumor vascular endothelial cells, position liposomes in tumor tissues, and concentrate drug in liposomes in tumor, so as to enhance the antitumor effect. The article starts with NGR peptides, summarizes definition of NGR, NGR peptide-modified liposomes, strengths and weaknesses of NGR peptide-modified liposomes in antitumor and the latest study orientation of NGR peptide-modified liposomes, and looks into the future of studies on NGR peptide-modified liposomes.
Animals ; Antineoplastic Agents ; pharmacology ; CD13 Antigens ; administration & dosage ; pharmacology ; Humans ; Liposomes ; Oligopeptides ; administration & dosage ; pharmacology

A few members of coronavirus group I which includes porcine epidemic diarrhea virus (PEDV) use porcine aminopeptidase N (pAPN) as a cellular receptor. Cellular receptors play an important role in virus attachment and entry. However, the low permissiveness of PEDV to APN-expressing porcine cell lines has made it difficult to elucidate the role of pAPN in vitro. The purpose of this study was to prove whether the treatment of soluble pAPN could enhance the antibody production against PEDV in guinea pigs, rabbits and sows. The animals (20 guinea pigs, 8 rabbits and 20 sows) were divided into 4 groups. Group A was injected intramuscularly (IM) with soluble pAPN at one hour before intramuscular infection of PEDV on the same site, group B for IM simultaneous injection of pAPN and PEDV, and group C for IM injection of PEDV only. Group D served as a control of pAPN treatment or PEDV infection. Antibody production against PEDV was compared among groups at regular intervals. The results suggested that pAPN could enhance the antibody production against PEDV in guinea pigs and rabbits which are free of pAPN, however, the effect of pAPN treatment in sows was not clearly elucidated.
Animals ; Antibodies, Viral/*blood ; Antibody Formation ; Antigens, CD13/*administration&dosage ; Cercopithecus aethiops ; Coronavirus/*immunology/physiology ; Coronavirus Infections/immunology/*veterinary ; Enzyme-Linked Immunosorbent Assay/veterinary ; Female ; Guinea Pigs ; Immunoglobulin G/*blood ; Immunoglobulin Isotypes ; Injections, Intramuscular ; Pregnancy ; Rabbits ; Solubility ; Swine ; Swine Diseases/*immunology ; Vero Cells/virology

OBJECTIVETo investigate whether phenylbutyrate (PB) combined with 5-aza-2'-deoxycytidine (5-Aza-CdR)could inhibit transcription repression and induce t(8;21) acute myelogenous leukemia (AML) Kasumi-1 cells to differentiate and undergo apoptosis.

METHODSKasumi-1 cells were treated with PB and 5-Aza-CdR at different concentrations in suspension culture. Cellular proliferation was determined by the MTT assay, expression of myeloid-specific differentiation antigen and cell cycles were analyzed by flow cytometry. Cell apoptosis were assessed using AnnexinV/PI staining and flow cytometry.

RESULTSTreatment of Kasumi-1 cells with PB caused a dose-dependent inhibition of proliferation, with an IC(50) of 2.3 mmol/L. When combined with 5-Aza-CdR, PB resulted in a greater growth inhibition with an IC(50) of 1.95 mmol/L. Treatment of Kasumi-1 cells with PB resulted in cell cycle arrest at G(0)/G(1), while combined treatment with PB and 5-Aza-CdR led to cell cycle arrest at G(2)/M. Expression of myeloid cell differentiation antigens CD11b and CD13 induced by PB was enhanced when Kasumi-1 cells were pretreated with low dose of 5-Aza-CdR. High, but not low, concentrations of 5-Aza-CdR could enhance early apoptosis of Kasumi-1 cells induced by PB.

CONCLUSIONPhenylbuty rate, when combined with 5-Aza-CdR, inhibits AML cell in vitro proliferation and increases apoptosis in a synergistic fashion.

Acute Disease ; Apoptosis ; drug effects ; Azacitidine ; administration & dosage ; analogs & derivatives ; pharmacology ; CD11b Antigen ; metabolism ; CD13 Antigens ; metabolism ; Cell Cycle ; drug effects ; Cell Line, Tumor ; Cell Proliferation ; drug effects ; Dose-Response Relationship, Drug ; Drug Synergism ; Humans ; Leukemia, Myeloid ; immunology ; pathology ; Phenylbutyrates ; pharmacology