In vitro efficiency and mechanistic role of indocyanine green as photodynamic therapy agent for human melanoma

Mamoon, Abdel-Megid; Gamal–Eldeen, Amira M.; Ruppel, Meghan E.; Smith, Randy J.; Tsang, Thomas; Miller, Lisa M.

doi:10.1016/j.pdpdt.2009.05.002

« Previous Next »Photodiagnosis and Photodynamic Therapy
Volume 6, Issue 2 , Pages 105-116, June 2009

In vitro efficiency and mechanistic role of indocyanine green as photodynamic therapy agent for human melanoma

Abdel-Megid Mamoon
- Egyptian Atomic Energy Authority, Nasr City, Cairo, Egypt
Amira M. Gamal–Eldeen
- Cancer Biology Laboratory, Center of Excellence for Advanced Sciences, National Research Center, Dokki 12622, Cairo, Egypt
- Cancer Biology Laboratory, Center of Excellence for Advanced Sciences, National Research Center, Dokki 12622, Cairo, Egypt. Tel.: +2 010 605 3903; fax: +2 02 333 709 31.
Meghan E. Ruppel
- Department of Biomedical Engineering, Stony Brook University, Stony Brook, NY, 11794, USA
Randy J. Smith
- National Synchrotron Light Source, Brookhaven National Laboratory, Upton, NY, 11973, USA
Thomas Tsang
- Instrumentation Division, Brookhaven National Laboratory, Upton, NY, 11973, USA
Lisa M. Miller, MS PhD
- Department of Biomedical Engineering, Stony Brook University, Stony Brook, NY, 11794, USA
- National Synchrotron Light Source, Brookhaven National Laboratory, Upton, NY, 11973, USA
- Corresponding author at: National Synchrotron Light Source, Bldg 725 D, Brookhaven National Laboratory, 75 Brookhaven Avenue, Upton, NY 11973-5000, USA. Tel.: +1 631 344 2091; fax: +1 631 344 3238.

published online 13 July 2009.

Summary

Background

Photodynamic therapy (PDT) is a promising treatment for superficial cancer. However, poor therapeutic results have been reported for melanoma, due to the high melanin content. Indocyanine green (ICG) has near infrared absorption (700–800nm) and melanins do not absorb strongly in this area. This study explores the efficiency of ICG as a PDT agent for human melanoma, and its mechanistic role in the cell death pathway.

Methods

Human skin melanoma cells (Sk-Mel-28) were incubated with ICG and exposed to a low power Ti:Sapphire laser. Synchrotron-assisted Fourier transform infrared microspectroscopy and hierarchical cluster analysis were used to assess the cell damage and changes in lipid, protein, and nucleic acids. The cell death pathway was determined by analysis of cell viability and apoptosis and necrosis markers.

Results

In the cell death pathway, ¹O₂ generation evoked rapid multiple consequences that trigger apoptosis after laser exposure for only 15min including the release of cytochrome c, the activation of total caspases, caspase-3, and caspase-9, the inhibition of NF-κB P65, and the enhancement of DNA fragmentation, and histone acetylation.

Conclusion

ICG/PDT can efficiently and rapidly induce apoptosis in human melanoma cells and it can be considered as a new therapeutic approach for topical treatment of melanoma.

Keywords: Photodynamic therapy, Human melanoma, Indocyanine green, Apoptosis, Infrared microspectroscopy, Hierarchical cluster analysis, Synchrotron