The effect of tumor necrosis factor alpha on a human renal cell carcinoma xenotransplanted into nude mice: comparison of intravenous and intraperitoneal injection.

The effect of recombinant human tumor necrosis factor alpha (TNF-alpha) on tumor growth and tumor cell proliferation of a human renal cell carcinoma transplanted into nude mice as well as on the body weight of the tumor-bearing animals has been studied. Due to differences of the effect of TNF-alpha after intravenous and intraperitoneal injection reported in the literature the influence of the two routes of application was presently studied. There was no effect on tumor growth with either route of application. Only the mode of growth showed a tendency to an increased rate of growth at the beginning of the treatment and a following increased growth deceleration. A slight change of the 3H-thymidine labeling index and the mitotic index was observed only after intraperitoneal injection of TNF-alpha indicative of a more cytostatic than cytotoxic effect of the drug. This is supported by the lack of an increase of necrotic cells. Although a rather high dose of TNF-alpha was applied, no effect on the body weight of the animals, i.e. no toxic effect of the treatment, has been found.