Influence of intravesical administration of tumor necrosis factor alpha and systemic gamma-interferon on murine bladder cancer: lack of dose response.

The effect of intravesical administration of high dose recombinant tumor necrosis factor-alpha (rTNF) and in combination with systemic recombinant gamma-interferon (rIFN) on murine bladder cancer was studied. RTNF was given at 12.5 micrograms/mouse on days 7, 11 and 15 after tumor instillation or at 2.5 micrograms/mouse on days 7, 9, 11, 13 and 15. Some groups were also injected i.v., 24-h prior to each rTNF treatment with rIFN at a dose of 1.3 micrograms/mouse. RTNF treatment suppressed tumor growth up to 48% of control, although the difference was not statistically significant. Combined administration of rIFN did not provide additional benefit.