Hypoxia-sensitive drug delivery to tumors

Nina Filipczak, Ujjwal Joshi, Sara Aly Attia, Ilana Berger Fridman, Smadar Cohen, Tania Konry

Research output: Contribution to journalArticlepeer-review


Achievement of a high dose of drug in the tumor while minimizing its systemic side effects is one of the important features of an improved drug delivery system. Thus, developing responsive carriers for site-specific delivery of chemotherapeutic agents has become a main goal of research efforts. One of the known hallmarks of cancerous tumors is hypoxia, which offers a target for selective drug delivery. The stimuli-sensitive micellar system developed by us, (PEG-azobenzene-PEI-DOPE (PAPD) has proven to be effective in vitro. The proposed construct developed, PAPD, contains an azobenzene group as a hypoxia-sensitive moiety that triggers the shedding of the PEG layer from the nanoparticle surface under conditions of hypoxia to improve cellular uptake. Using microfluidics, we show significantly improved cellular association and penetration under hypoxia in both single cells and in a 3D tumor model. Employing an in vivo model, we demonstrate slower tumor growth that did not induce systemic side effects, including weight loss in an experimental animal model, when compared to the free drug treatment. This complex-in-nature but simple-in-design system for the simultaneous delivery of siRNA to silence the P-glycoprotein and doxorubicin with active tumor targeting and proven therapeutic efficacy represents a universal platform for the delivery of other hydrophobic chemotherapeutic agents and siRNA molecules which can be further modified.

Original languageAmerican English
Pages (from-to)431-442
Number of pages12
JournalJournal of Controlled Release
StatePublished - 1 Jan 2022


  • Doxorubicin
  • Hypoxia
  • Microfluidic single cell analysis
  • Nanoparticles
  • PEG
  • Polymeric micelles
  • siRNA

All Science Journal Classification (ASJC) codes

  • Pharmaceutical Science


Dive into the research topics of 'Hypoxia-sensitive drug delivery to tumors'. Together they form a unique fingerprint.

Cite this