Characterization of a microsphere formulation containing glucose oxidase and its in vivo efficacy in a murine solid tumor model.

Purpose: This work focused on the characterization and in vitro/in vivo evaluation of an alginate/chitosan microsphere (ACMS) formulation of glucose oxidase (GOX) for the locoregional delivery of reactive oxygen species for the treatment of solid tumors.

Methods: The GOX distribution and ACMS composition were determined by confocal laser scanning microscopy and X-ray photoelectron spectroscopy. The mechanism of GOX loading and GOX-polymer interactions were examined with Fourier transform infrared spectroscopy and differential scanning calorimetry.

Localization of P-glycoprotein at the nuclear envelope of rat brain cells.

P-glycoprotein is a plasma membrane drug efflux protein implicated in extrusion of cytotoxic compounds out of a cell. There is now evidence that suggests expression of this transporter at several subcellular sites, including the nucleus, mitochondria, and Golgi apparatus. This study investigated the localization and expression of P-glycoprotein at the nuclear membrane of rat brain microvessel endothelial (RBE4) and microglial (MLS-9) cell lines.

Expression of the ATP-binding cassette membrane transporter, ABCG2, in human and rodent brain microvessel endothelial and glial cell culture systems.

Purpose: The function of ABCG2 (BCRP), a member of the ATP-binding cassette (ABC) superfamily of membrane-associated drug transporters, at the blood-brain barrier remains highly controversial. This project investigates the functional expression of endogenous ABCG2 in cultures of human and rodent brain cellular compartments.

Materials And Methods: RT-PCR, western blot and fluorescent immunocytochemical analyses were performed on ABCG2-overexpressing human breast cancer (MCF-MX100) cells, human and rat brain microvessel endothelial (HBEC and RBE4, respectively), and rat glial cells.

A mechanistic study of enhanced doxorubicin uptake and retention in multidrug resistant breast cancer cells using a polymer-lipid hybrid nanoparticle system.

The objectives of this study were to evaluate the potential of a polymer-lipid hybrid nanoparticle (PLN) system to enhance cellular accumulation and retention of doxorubicin (Dox), a widely used anticancer drug and an established P-glycoprotein (Pgp) substrate, in Pgp-overexpressing cancer cell lines and to explore the underlying mechanisms. Nanoparticles containing Dox complexed with a novel anionic polymer (Dox-PLN) were prepared using an ultrasound method. Two Pgp-overexpressing breast cancer cell lines (a human cell line, MDA435/LCC6/MDR1, and a mouse cell line, EMT6/AR1) were used to investigate the effect of nanoparticles on cellular uptake and retention of Dox.