Peptide NGR Modified TiO_(2) Nanofiber Substrate for Circulating Tumor Cells Capture

The analysis of circulating tumor cells(CTCs)allows a noninvasive method of“real-time liquid biopsy”from the blood samples of cancer patients for the diagnosis of early-stage cancer,prognosis,and monitoring therapeutic response.In this study,we develop a simple,inexpensive,and reliable method that utilizes a small molecule peptide,the asparagine-glycine-arginine(NGR),as a capture probe for the selective enrichment and isolation of circulating tumor cells(CTCs).The multiscale TiO_(2) nanofibers are obtained by electrospinning and calcination.Bovine serum albumin(BSA)is decorated onto TiO_(2) nanofiber surfaces to inhibit non-target cell adhesion,while NGR peptides are conjugated onto the TiO_(2)-BSA surface through the glutaraldehyde(GA)to specifically capture the target cells.The TiO_(2)-BSA-NGR substrate exhibits a high capture sensitivity and efficiency from the mimical blood samples with PC-3 cancer cells as low as 10 cells/mL.The TiO_(2) nanofiber substrate can be a promising strategy for the capture and enumeration of CTCs in cancer progression monitoring.

Anti-tumor targeted drug delivery systems mediated by aminopeptidase N/CD13

Aminopeptidase N(APN)/CD13 is a transmembrane glycoprotein,which is overexpressed on tumor neovascular endothelial cells and most tumor cells,where it plays an important role in tumor angiogenesis.Peptides containing the Asn-Gly-Arg(NGR)motif can specifically recognize APN/CD13 allowing them to act as tumor-homing peptides for the targeted delivery of anti-tumor drugs to tumor neovascular endothelial cells and tumor cells.This article reviews the literature and recent developments related to APN/CD13,its role in tumor growth and some antitumor drug delivery systems containing NGR peptides designed to target APN/CD13.