[Antitumor effect of PSK and its combined effect with CDDP on ovarian serous adenocarcinoma-bearing nude mice].
Although the antitumor effect of PSK can be increased by potentiating the immune functions of PSK in tumor-bearing hosts, the mechanisms of its action are not fully understood. In this study, we examined the antitumor effect and CDDP combined effect of oral administration of PSK on nude mice bearing a human ovarian cancer cell line (KF cells). 1. PSK was observed to have a significant antitumor effect in tumor-bearing nude mice and subsequently to bring about an increase in the survival rate and prolongation of the life span. 2. The antitumor effect of CDDP was (but not significantly) enhanced by oral administration of PSK and the prolongation of the life span of the tumor-bearing nude mice was obtained. 3. Six weeks after tumor inoculation, no significant natural killer (NK) cell activity in spleen cells from untreated nude mice was observed. However, when PSK (100 mg/kg but not 500 mg/kg) was given every other day, significant NK activity was induced. 4. The serum immunosuppressive acid protein (IAP) value in nude mice treated with PSK alone was significantly higher than that in nude mice treated with a combination of PSK (100 mg/kg) and CDDP. These results suggest that CDDP prevents the increase in serum IAP that occurs when PSK is used and that consequently combinations of PSK and CDDP result in augmentation of antitumor effects.
Department of Obstetrics and Gynecology, National Defense Medical College, Saitama.
K
K
Ishii
T
T
Kita
J
J
Hirata
T
T
Tode
Y
Y
Kikuchi
I
I
Nagata
D000818:Animals; D000903:Antibiotics, Antineoplastic / Q000008:administration & dosage; D000971:Antineoplastic Combined Chemotherapy Protocols / Q000627:therapeutic use*; D002945:Cisplatin / Q000008:administration & dosage; D003536:Cystadenocarcinoma / Q000188:drug therapy* / Q000276:immunology / Q000401:mortality; D003602:Cytotoxicity, Immunologic; D005260:Female; D006801:Humans; D007155:Immunologic Factors; D051379:Mice; D008819:Mice, Nude; D009363:Neoplasm Proteins / Q000097:blood; D009368:Neoplasm Transplantation; D010051:Ovarian Neoplasms / Q000188:drug therapy* / Q000276:immunology / Q000401:mortality; D011509:Proteoglycans / Q000008:administration & dosage; D015996:Survival Rate
D000903:Antibiotics, Antineoplastic; D007155:Immunologic Factors; D009363:Neoplasm Proteins; D011509:Proteoglycans; C030193:immunosuppressive acidic protein; C010770:polysaccharide-K; D002945:Cisplatin