Polymer-drug conjugates for intracellar molecule-targeted photoinduced inactivation of protein and growth inhibition of cancer cells

Sci Rep. 2012;2:766. doi: 10.1038/srep00766. Epub 2012 Oct 24.


For most molecule-targeted anticancer systems, intracellular protein targets are very difficult to be accessed by antibodies, and also most efforts are made to inhibit protein activity temporarily rather than inactivate them permanently. In this work we firstly designed and synthesized multifunctional polymer-drug conjugates (polythiophene-tamoxifen) for intracellular molecule-targeted binding and inactivation of protein (estrogen receptor α, ERα) for growth inhibition of MCF-7 cancer cells. Small molecule drug was conjugated to polymer side chain for intracellular signal protein targeting, and simultaneously the fluorescent characteristic of polymer for tracing the cellular uptake and localization of polythiophene-drug conjugates by cell imaging. Under light irradiation, the conjugated polymer can sensitize oxygen to produce reactive oxygen species (ROS) that specifically inactivate the targeted protein, and thus inhibit the growth of tumor cells. The conjugates showed selective growth inhibition of ERα positive cancer cells, which exhibits low side effect for our intracellular molecule-targeted therapy system.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Antineoplastic Agents, Hormonal / administration & dosage
  • Antineoplastic Agents, Hormonal / chemistry*
  • Antineoplastic Agents, Hormonal / pharmacology
  • Breast Neoplasms / drug therapy
  • Cell Proliferation / drug effects
  • Drug Carriers / chemistry*
  • Estrogen Receptor alpha / antagonists & inhibitors*
  • Estrogen Receptor alpha / metabolism
  • Female
  • Humans
  • Light
  • MCF-7 Cells
  • Microscopy, Fluorescence
  • Photochemotherapy
  • Polymers / chemistry*
  • Reactive Oxygen Species / metabolism
  • Tamoxifen / administration & dosage
  • Tamoxifen / chemistry*
  • Tamoxifen / pharmacology
  • Thiophenes / chemistry*


  • Antineoplastic Agents, Hormonal
  • Drug Carriers
  • Estrogen Receptor alpha
  • Polymers
  • Reactive Oxygen Species
  • Thiophenes
  • Tamoxifen
  • polythiophene