Tumor hypoxia, the Warburg effect, and multidrug resistance: Modulation of hypoxia induced MDR using EGFR-targeted polymer blend nanocarriers for combination paclitaxel/lonidamine therapy.

摘要

Multi-drug resistant (MDR) cancer is a significant clinical obstacle and is often implicated in cases of recurrent, non-responsive disease. The biological focus of this work is to explore the relationship between the hypoxic microenvironment of a tumor, the development of MDR, and the energetic profile characteristic of the Warburg effect (aerobic glycolysis). The therapeutic aim of this research is to develop an EGFR-targeted nanocarrier system for combination (paclitaxel/lonidamine) therapy for the treatment of MDR cancer.;The stability of the nanocarrier formulation was validated in vitro and the system was characterized for drug release kinetics, size, surface modification, and EGFR-targeting ability. An orthotopic animal model of hypoxic, MDR breast cancer was developed for the pre-clinical evaluation of this system. The EGFR-targeted nanoparticles loaded with lonidamine and paclitaxel demonstrated superior pharmacokinetic parameters relative to non-targeted nanoparticles and drug solution. Combination therapy with lonidamine and paclitaxel, in solution and EGFR-targeted nanoparticle form, was more effective at suppressing tumor growth than single agent treatment. However, combination therapy with EGFR-targeted nanoparticles was less toxic than treatment with drug solution. Combination therapy did change the MDR and hypoxic character of the tumors as demonstrated by a decrease in marker proteins. This EGFR-targeted combination nanocarrier therapy has the potential to make the successful treatment of MDR a clinical reality.