[The effect of local injection of interferon against human malignant glioma transplanted into nude mice and the mechanism of its effect].

In order to clarify the mechanism of action of recombinant human leucocyte interferon, the effect of local injection of it to the human malignant gliomas (one oligodendroglioma, the other glioblastoma) transplanted into nude mice were evaluated. The volume of the tumors were calculated as 1/2 (short diameter [cm])2 x (long diameter[cm]). And the ratio of tumor volume (T)/original size (C) were calculated in terms of experimental day. Among the groups of control (vehicle of IFN injected), 1 million units of IFN locally injected group, 3 million units injected group, and 9 million units injected group, the effects of the treatment were statistically evaluated in terms of T/C. At the end of the experiment, each animal was injected 4 mg of BrdU intraperitoneally, and the labeling indices of the tumor tissue were measured and compared among the groups above mentioned. Local injection of IFN to the tumor was effective even at the dose of 1 million units every other day for 16 days for glioblastoma and 50 days for oligodendroglioma. The labeling index of the treated groups was significantly reduced when compared to that of control group in both tumors. And the experiment was performed to evaluate the variation of NK activity and ADCC activity of mouse spleen cells among the experimental groups. For the oligodendroglioma, NK activities were significantly increased in the 9 million units of IFN injected group when compared to those of control group. For glioblastoma, there was no definite variation of NK and ADCC activities among the groups.(ABSTRACT TRUNCATED AT 250 WORDS)