Effects of photoactivated 5-aminolevulinic acid hexyl ester on MDR1 over-expressing human uterine sarcoma cells

Toxicol Lett. 2008 Sep;181(1):7-12. doi: 10.1016/j.toxlet.2008.06.860. Epub 2008 Jun 25.

Abstract

The role of multi-drug resistance (MDR1) and its product, P-glycoprotein (P-gp) on 5-aminolevulinic acid hexyl ester (Hexyl-ALA) mediated phototoxicity was determined with human uterine sarcoma cells, MES-SA control and MDR1 expressing MES-SA-Dx5. MDR1 expression reduced intracellular levels of the Hexyl-ALA metabolite, protoporphyrin IX (PpIX) to a limited degree and could be reversed with a P-gp inhibitor, verapamil. P-gp expression also reduced Hexyl-ALA photosensitivity. More importantly, photoactivated Hexyl-ALA reduced at the mRNA and protein levels without altering housekeeping GAPDH mRNA. These findings suggest that Hexyl-ALA could be used to selectively reduce P-gp expression in overcoming resistance to chemotherapy agents such as doxorubicin and paclitaxel.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • ATP Binding Cassette Transporter, Subfamily B
  • ATP Binding Cassette Transporter, Subfamily B, Member 1 / antagonists & inhibitors
  • ATP Binding Cassette Transporter, Subfamily B, Member 1 / genetics
  • ATP Binding Cassette Transporter, Subfamily B, Member 1 / physiology*
  • Aminolevulinic Acid / analogs & derivatives*
  • Aminolevulinic Acid / pharmacology
  • Cell Line, Tumor
  • Female
  • Humans
  • Photochemotherapy*
  • RNA, Messenger / analysis
  • Sarcoma / drug therapy*
  • Sarcoma / pathology
  • Uterine Neoplasms / drug therapy*
  • Uterine Neoplasms / pathology
  • Verapamil / pharmacology

Substances

  • ABCB1 protein, human
  • ATP Binding Cassette Transporter, Subfamily B
  • ATP Binding Cassette Transporter, Subfamily B, Member 1
  • RNA, Messenger
  • Aminolevulinic Acid
  • Verapamil
  • 5-aminolevulinic acid hexyl ester