Enhancement of the photodynamic antitumor effect by streptococcal preparation OK-432 in the mouse carcinoma |
| |
Authors: | Masataka Uehara Kazuo Sano Zuo-Lin Wang Joji Sekine Hisazumi Ikeda Tsugio Inokuchi |
| |
Institution: | (1) Second Department of Oral and Maxillofacial Surgery, Nagasaki University School of Dentistry, 1-7-1 Sakamoto, Nagasaki 852-8588, Japan e-mail: uehara@net.nagasaki-u.ac.jp, JP |
| |
Abstract: | Biological response modifier antitumor effects are enhanced by the activation of the host defense mechanisms. We have investigated
the antitumor effect of photodynamic therapy (PDT) and/or local administration of a biological response modifier, the streptococcal
preparation OK-432, on transplanted NR-S1 mouse squamous cell carcinoma. Hematoporphyrin oligomers (20 mg/kg body weight)
were used to photosensitize PDT. A pulsed Nd:YAG dye laser, tuned at 630 nm, was used as the light source. The laser power
was 15 mJ cm−2 pulse−1, and the irradiation time was 40 min. The photosensitizer was injected intraperitoneally 48 h before laser irradiation. Where
used, OK-432 was injected into the tumor either 3 h prior to PDT or immediately afterwards. The antitumor effects were evaluated
48 h after each protocol by (a) estimating the area of tumor necrosis (%) in hematoxylin/eosin-stained specimens, and (b)
bromodeoxyuridine immunohistochemistry. Furthermore, the tumor sizes were evaluated 3, 7 and 10 days after each protocol,
and the survival time after each protocol was evaluated as well. The anti-tumor effect of PDT was enhanced by administration
of OK-432 3 h before PDT, whereas the administration of OK-432 immediately after PDT did not potentiate a PDT antitumor effect.
Treatment with OK-432 alone had little effect on tumors. Photodynamic therapy in combination with local administration of
OK-432 3 h before PDT is considered to be a useful treatment modality.
Received: 23 July 1999 / Accepted: 31 May 2000 |
| |
Keywords: | Photodynamic therapy OK-432 Biological response modifier Combined therapy In vivo |
本文献已被 PubMed SpringerLink 等数据库收录! |
|