Photodynamic therapy for human oral squamous cell carcinoma and xenografts using a new photosensitizer, PAD-S31.

Abstract

BACKGROUND AND OBJECTIVES:

Photodynamic therapy (PDT) is a novel and promising cancer treatment that employs a combination of photosensitizer and visible light. We examined the effect of PDT using a new photosensitizer, PAD-S31, and the 670-nm diode laser in human oral squamous cell carcinomas (SCC).

STUDY DESIGN/MATERIALS AND METHODS:

SAS and HSC-4 cell lines were used in all the experiments. Cell viability was determined by a modified MTT assay. Two methods were used for the determination of apoptosis in human oral SCC cells: TUNEL assay and detection of fragmented mono- and oligo-nucleosomes by ELISA. Xenografts of human oral SCC cells were generated in KSN S1c nude mice.

RESULTS:

In vitro PDT using PAD-S31 and the 670-nm diode laser showed cytotoxicity that was a function of laser energy, drug concentration, and time to the SAS and HSC-4 cell lines. On the other hand, PAD-S31 without irradiation had no effect on cell viability. The combinated use of PAD-S31 and the laser irradiation showed excellent anti-tumor activity against tumor xenografts without severe side effects. PDT-mediated cell death occurred predominantly by apoptosis in vitro and in vivo.

CONCLUSIONS:

The present study demonstrates that PAD-S31 may serve as a potent photosensitizer for PDT. Furthermore, it is expected that this therapy will be clinically useful for the treatment of patients with oral carcinoma.

• Authors: Masataka Date, Isao Sakata, Kazuhide Fukuchi, Kiyoshi Ohura, Yasutaka Azuma, Mitsuko Shinohara, Koichi Matsuzaki, Yoshihisa Namiki, Hiroshi Takahashi
• Journal: Lasers in surgery and medicine (Lasers Surg Med) Vol. 33 Issue 1 Pg. 57-63 ( 2003) ISSN: 0196-8092 [Print] United States
• PMID: 12866122 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)
• Copyright: Copyright 2003 Wiley-Liss, Inc.

Chemical References

• 13,17-bis(1-carboxypropionyl)carbamoylethyl-3-ethenyl-8-ethoxyiminoethylidene-7-hydroxy-2,7,12,18-tetramethyl porphyrin
• Photosensitizing Agents
• Porphyrins

Topics

• Animals
• Apoptosis (drug effects, radiation effects)
• Carcinoma, Squamous Cell (drug therapy, pathology)
• Cell Line, Tumor
• Disease Models, Animal
• Enzyme-Linked Immunosorbent Assay
• Humans
• In Situ Nick-End Labeling
• In Vitro Techniques
• Mice
• Mice, Nude
• Mouth Neoplasms (drug therapy, pathology)
• Photochemotherapy
• Photosensitizing Agents (therapeutic use)
• Porphyrins (therapeutic use)
• Transplantation, Heterologous