Therapeutic effect of photodynamic therapy using PAD-S31 and diode laser on human liver cancer cells.

Abstract

BACKGROUND/AIMS:

Photodynamic therapy (PDT) is an effective local cancer treatment which a photosensitizer is administered and the tumor is irradiated with light. We examined the effect of PDT using PAD-S31 as the photosensitizer, and the 670 nm diode laser on human hepatocellular carcinomas (HCCs).

METHODS:

Huh-7, HepG2 and Hep3B cell lines were used in the all experiments. Cell viability was determined by a modified MTT assay. Two methods were used for the determination of apoptosis: terminal deoxynucleotidyl transferase (TdT)-mediated dUTP nick-end labeling assay and detection of fragmented mono- and oligo-nucleosomes by enzyme-linked immunosorbent assay. The caspase activity was measured by fluorometric assay. Cytochrome c in cytosolic fraction was determined using a human cytochrome c immunoassay. Xenografts of human oral HCC cells were generated in KSN S1c nude mice.

RESULTS:

In vitro PDT showed excellent cytotoxicity that was a function of laser energy, drug concentration and time to the hepatoma cell lines. The combined use of PAD-S31 and laser irradiation showed excellent anti-tumor activity without severe side-effect against human hepatoma xenografts in nude mice. PDT-mediated cell death occurred predominantly by apoptosis in vitro and in vivo. Furthermore, this treatment initiates early cytochrome c release, followed by late caspase-3 and -9 activation.

CONCLUSION:

Our study demonstrates that PDT using PAD-S31 and the diode laser induces apoptosis that is mediated by cytochrome c release and caspase activation in human liver cancer cell lines. It is expected that this therapy will be clinically useful for the treatment of patients with HCC.

• Authors: Masataka Date, Kazuhide Fukuchi, Yoshihisa Namiki, Akihiko Okumura, Shosuke Morita, Hiroshi Takahashi, Kiyoshi Ohura
• Journal: Liver international : official journal of the International Association for the Study of the Liver (Liver Int) Vol. 24 Issue 2 Pg. 142-8 (Apr 2004) ISSN: 1478-3223 [Print] United States
• PMID: 15078479 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)
• Copyright: Copyright Blackwell Munksgaard 2004

Chemical References

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

Topics

• Animals
• Antineoplastic Agents (pharmacology, therapeutic use)
• Apoptosis (drug effects)
• Carcinoma, Hepatocellular (drug therapy, pathology)
• Cell Line, Tumor (drug effects)
• Dose-Response Relationship, Drug
• Humans
• In Situ Nick-End Labeling
• Lasers
• Liver Neoplasms (drug therapy, pathology)
• Male
• Mice
• Mice, Inbred Strains
• Mice, Nude
• Neoplasm Transplantation
• Neoplasms, Experimental (drug therapy, pathology)
• Photochemotherapy
• Photosensitizing Agents (pharmacology, therapeutic use)
• Porphyrins (pharmacology, therapeutic use)