title: Enhancement of the photodynamic antitumor effect by streptococcal preparation OK-432 in the mouse carcinoma.
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 antitumor 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.
authors.affiliation: Second Department of Oral and Maxillofacial Surgery, Nagasaki University School of Dentistry, Japan. uehara@net.nagasaki-u.ac.jp
authors.forename: M
authors.initials: M
authors.lastname: Uehara
authors.forename: K
authors.initials: K
authors.lastname: Sano
authors.forename: Z L
authors.initials: ZL
authors.lastname: Wang
authors.forename: J
authors.initials: J
authors.lastname: Sekine
authors.forename: H
authors.initials: H
authors.lastname: Ikeda
authors.forename: T
authors.initials: T
authors.lastname: Inokuchi
mesh_terms: D000818:Animals; D000970:Antineoplastic Agents / Q000008:administration & dosage / Q000627:therapeutic use*; D001973:Bromodeoxyuridine / Q000378:metabolism; D002294:Carcinoma, Squamous Cell / Q000188:drug therapy / Q000276:immunology / Q000473:pathology / Q000628:therapy*; D003131:Combined Modality Therapy; D007150:Immunohistochemistry; D008297:Male; D051379:Mice; D008809:Mice, Inbred C3H; D009336:Necrosis; D009368:Neoplasm Transplantation; D009504:Neutrophils / Q000187:drug effects / Q000276:immunology / Q000473:pathology; D010778:Photochemotherapy / Q000379:methods*; D010844:Picibanil / Q000008:administration & dosage / Q000627:therapeutic use*; D013997:Time Factors; D016896:Treatment Outcome; D014407:Tumor Cells, Cultured
chemical_list: D000970:Antineoplastic Agents; D010844:Picibanil; D001973:Bromodeoxyuridine