A quantitative method for screening and identifying molecular targets for nanomedicine

Abstract

Identifying a molecular target is essential for tumor-targeted nanomedicine. Current cancer nanomedicines commonly suffer from poor tumor specificity, “off-target” toxicity, and limited clinical efficacy. Here, we report a method to screen and identify new molecular targets for tumor-targeted nanomedicine based on a quantitative analysis. In our proof-of-principle study, we used comparative flow cytometric screening to identify ICAM-1 as a potential target for metastatic melanoma (MM). We further evaluated ICAM-1 as a MM targeting moiety by characterizing its (1) tumor specificity, (2) expression level, (3) cellular internalization, (4) therapeutic function, and (5) potential clinical impact. Quantitation of ICAM-1 protein expression on cells and validation by immunohistochemistry on human tissue specimens justified the synthesis of antibody-functionalized drug delivery vehicles, which were benchmarked against appropriate controls. We engineered ICAM-1 antibody conjugated, doxorubicin encapsulating immunoliposomes (ICAM-Dox-LPs) to selectively recognize and deliver doxorubicin to MM cells and simultaneously neutralize ICAM-1 signaling via an antibody blockade, demonstrating significant and simultaneous inhibitory effects on MM cell proliferation and migration. This paper describes a novel, quantitative metric system that identifies and evaluates new cancer targets for tumor-targeting nanomedicine.

ICAM-1: A master regulator of cellular responses in inflammation, injury resolution, and tumorigenesis

“…In another setting, ICAM-1 was engineered as a target moiety to deliver doxorubicin-conjugated liposomes to metastatic melanoma and enhanced drug uptake by these cancer cells. 194…”

ITGA2 as a potential nanotherapeutic target for glioblastoma

“…Identifying new GBM targets holds the key to the development of GBM-targeted therapeutics. Thus, we performed an unbiased and quantitative screening of a panel of 70 cancer-related cell surface antigens on three well-established human GBM cell lines (A172, U87, and U118) in comparison with non-neoplastic human glial SVG-P12 cells (normal control) by flow cytometric analysis as previously reported 13 (Fig. 1a).…”

“…The cell surface expression of 70 cancer-related antigens was evaluated using a BD FACSCalibur Flow Cytometer (BD Biosciences, San Jose, CA, USA) as previously described 13,46 . Surface antigen density on target cell surfaces was quantified using Quantum Simply Cellular microbeads as a reference and was conducted according to the protocol provided by the manufacturer.…”

Nanomaterial Preparation by Extrusion through Nanoporous Membranes

“…A liposome is a spherical synthetic lipid vesicle composed of a single lipid bilayer with a nanoscale diameter ranging from 60 nm to a few micrometers. Due to their unique hollow structure, liposomes have been widely used as a drug delivery system to protect and deliver therapeutic agents including chemodrugs, small molecule inhibitors, siRNAs, DNAs, proteins/peptides, and recently developed CRISPR‐Cas gene editing systems . The surface of liposomes is frequently modified with polyethylene glycol (PEG) to reduce cell uptake by immune cells and extend the liposome blood circulation time .…”