Selective cancer treatment via photodynamic sensitization of hypoxia-responsive drug delivery

Nanoscale. 2018 Feb 8;10(6):2856-2865. doi: 10.1039/c7nr07677k.

Abstract

The precise and selective delivery of chemodrugs into tumors represents a critical requirement for anti-cancer therapy. Intelligent delivery systems that are responsive to a single internal or external stimulus often lack sufficient cancer selectivity, which compromises the drug efficacy and induces undesired side effects. To overcome this dilemma, we herein report a cancer-targeting vehicle which allows highly cancer-selective drug release in response to cascaded external (light) and internal (hypoxia) dual triggers. In particular, doxorubicin (DOX)-loaded, hypoxia-dissociable nanoparticles (NPs) were prepared from self-assembled polyethylenimine-nitroimidazole (PEI-NI) micelles that were further co-assembled with hyaluronic acid-Ce6 (HC). Upon accumulation in tumor cells, tumor site-specific light irradiation (660 nm, 10 mW cm-2) generated high levels of reactive oxygen species (ROS) and greatly enhanced the hypoxic levels to induce NP dissociation and accordingly DOX release. A synergistic anti-cancer efficacy between DOX-mediated chemotherapy and Ce6-mediated photodynamic therapy (PDT) was thus achieved, resulting in reduced side effects to normal tissues/cells. This study therefore provides an effective method to control the cancer-specific drug delivery by responding to cascaded multiple triggers, and it renders promising applications for the programmed combination of chemotherapy and PDT toward cancer treatment.

MeSH terms

  • Animals
  • Cell Line, Tumor
  • Doxorubicin / administration & dosage*
  • Drug Delivery Systems*
  • Female
  • Hyaluronic Acid
  • Hypoxia
  • Mice, Inbred C57BL
  • Micelles
  • Nanoparticles*
  • Neoplasms, Experimental / therapy*
  • Nitroimidazoles
  • Photoacoustic Techniques
  • Photochemotherapy*
  • Polyethyleneimine
  • Tissue Distribution

Substances

  • Micelles
  • Nitroimidazoles
  • Doxorubicin
  • Polyethyleneimine
  • Hyaluronic Acid