Antitumor activity of interleukin-12 against murine bladder cancer.
OBJECTIVE
We investigated the antitumor activity of interleukin-12 (IL-12) against MBT-2, a murine bladder carcinoma, to clarify whether or not IL-12 is effective against urothelial tumors.


METHODS
MBT-2, a murine carcinogen-induced, poorly differentiated transitional cell carcinoma of C3H/He origin, was used. Three or 10 days after the subcutaneous administration of MBT-2 cells, C3H/He mice were injected intraperitoneally with IL-12 five times per wk. for 2 wk. Tumor growth was measured twice weekly. Spleen cells from the C3H/He mice that had rejected MBT-2 after the IL-12 treatment were examined for MBT-2-specific cytolytic T lymphocytes (CTL) activity and cytokine production.


RESULTS
Tumor growth and acceptance was obviously suppressed when C3H/He mice were treated with IL-12 from 3 days after the tumor inoculation. In the spleen cells from the C3H/He mice that had rejected MBT-2, MBT-2-specific CTL activity and secretion of IL-2 and interferon (IFN)-gamma were clearly detected. However, the established MBT-2 tumor cells were not rejected when C3H/He mice were given IL-12 from 10 days after the tumor inoculation, although the tumor growth was transiently suppressed during the IL-12 treatment.


CONCLUSIONS
These data demonstrate that IL-12 is considerably effective against murine bladder cancer and suggest the clinical application of IL-12 against human bladder cancer.
Eto
M
M
Department of Urology, Faculty of Medicine, Medical Institute of Bioregulation, Kyushu University, Fukuoka, Japan.
Harada
M
M
Tamada
K
K
Tokuda
N
N
Koikawa
Y
Y
Nakamura
M
M
Nomoto
K
K
Naito
S
S
D000276:Adjuvants, Immunologic / Q000627:therapeutic use*; D000818:Animals; D002295:Carcinoma, Transitional Cell / Q000188:drug therapy*; D004354:Drug Screening Assays, Antitumor; D005260:Female; D018664:Interleukin-12 / Q000627:therapeutic use*; D051379:Mice; D008809:Mice, Inbred C3H; D001749:Urinary Bladder Neoplasms / Q000188:drug therapy*
D000276:Adjuvants, Immunologic; D018664:Interleukin-12