A physiological role of interferon (IFN)-beta derived from tumor: tumor growth of a mouse bladder carcinoma line MBT-2 is partially suppressed by autocrine IFN-beta.
Although some tumor cells endogenously produce a wide variety of cytokines, their physiological roles remain to be fully understood. In this study, we found that mouse subcutaneous tumor induced by inoculation of bladder tumor MBT-2 cells into syngeneic mice secreted a significant amount of interferon (IFN), whereas the cells exhibited no IFN production in in vitro cell culture. Typing experiment using IFN-specific neutralizing antibodies showed that the tumor-derived IFN was exclusively beta type. Since the MBT-2 tumor tissues were homogenous and not infiltrated by immune cells, MBT-2 cells themselves were considered to be IFN-beta producers. By intraperitoneal injection of neutralizing anti-IFN-beta antibodies into MBT-2 cell-inoculated mice, the tumor growth was substantially precipitated and survival days of the tumor-bearing mice were shortened. As the in vitro cell growth of MBT-2 cells was dose-dependently inhibited by IFN-beta, it was suggested that apparent immunogenicity of MBT-2 tumor is partially mediated by tumor suppression by autocrine IFN-beta.
Kawabata
K
K
Department of Drug Delivery Research, Faculty of Pharmaceutical Sciences, Kyoto University, Japan.
Okamoto
S
S
Takakura
Y
Y
Hashida
M
M
Hashimura
T
T
Watanabe
Y
Y
D000818:Animals; D000911:Antibodies, Monoclonal; D000970:Antineoplastic Agents / Q000032:analysis* / Q000276:immunology / Q000494:pharmacology; D004305:Dose-Response Relationship, Drug; D005260:Female; D016899:Interferon-beta / Q000276:immunology / Q000494:pharmacology / Q000502:physiology*; D051379:Mice; D008809:Mice, Inbred C3H; D009368:Neoplasm Transplantation; D014407:Tumor Cells, Cultured / Q000187:drug effects; D001749:Urinary Bladder Neoplasms / Q000737:chemistry* / Q000401:mortality / Q000473:pathology
D000911:Antibodies, Monoclonal; D000970:Antineoplastic Agents; D016899:Interferon-beta