Interest of RGD-containing linear or cyclic peptide targeted tetraphenylchlorin as novel photosensitizers for selective photodynamic activity

Bioorg Chem. 2007 Jun;35(3):205-20. doi: 10.1016/j.bioorg.2006.11.005. Epub 2006 Dec 9.

Abstract

Destruction of the neovasculature is essential for tumor eradication by photodynamic therapy. Since the over-expression of integrins is correlated with tumor angiogenesis, we conjugated a photosensitizer (5-(4-carboxyphenyl)-10,15,20-triphenylchlorin or porphyrin) to the alpha(v)beta(3) integrin specific peptide RGD (H-Arg-Gly-Asp-OH) motif as a common sequence. We reported an efficient solid-phase synthesis of a new family of peptidic photosensitizers with linear or cyclic[RGDfK] RGD motif and compared conjugates in vitro selectivity and photodynamic activity. The conjugates were characterized by (1)H NMR, MALDI, UV-visible spectroscopy and singlet oxygen formation was performed. Chlorins containing linear and constrained RGD motif were incorporated up to 98- and 80-fold more, respectively, than the unconjugated photosensitizer over a 24-h exposure in human umbilical vein endothelial cells (HUVEC) over-expressing alpha(v)beta(3) integrin. Peptidic moiety also led to a non-specific increased cellular uptake by murine mammary carcinoma cells (EMT-6), lacking RGD binding receptors. Survival measurements demonstrated that HUVEC were greatly sensitive to conjugates-mediated photodynamic therapy.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Cell Line
  • Cell Survival / drug effects
  • Drug Screening Assays, Antitumor
  • Endothelial Cells / drug effects
  • Endothelial Cells / radiation effects
  • Humans
  • Integrin alphaVbeta3 / biosynthesis
  • Integrin alphaVbeta3 / chemistry*
  • Mammary Neoplasms, Animal / drug therapy*
  • Mice
  • Molecular Structure
  • Peptides / chemistry*
  • Peptides, Cyclic / chemistry*
  • Photochemotherapy / methods
  • Photosensitizing Agents / chemical synthesis
  • Photosensitizing Agents / chemistry*
  • Photosensitizing Agents / pharmacology
  • Porphyrins / chemical synthesis
  • Porphyrins / chemistry*
  • Porphyrins / pharmacology
  • Structure-Activity Relationship

Substances

  • 5-(4-carboxyphenyl)-10,15,20-triphenylchlorin
  • Integrin alphaVbeta3
  • Peptides
  • Peptides, Cyclic
  • Photosensitizing Agents
  • Porphyrins