Abstract: | The antitumor activity of 27 anticancer drugs against a human breast cancer tumor (MX-1) has been studied using the subrenal capsule assay developed by A.E. Bogden et al. in 1978. Without immunosuppression with cyclophosphamide, BDF1 mice transplanted with MX-1 were treated with various drugs. The antitumor activity was evaluated by the tumor growth inhibition rate on day 6 after treatment. Among the 27 anticancer drugs tested, 10 compounds (37%) which showed more than 75% tumor growth inhibition rate were considered to be active. On the other hand, 8 compounds out of 27 drugs (30%) which showed less than 50% tumor growth inhibition rate were considered to be inactive. When the antitumor activity between the subrenal capsule assay in BDF1 mice and the subcutaneous transplantation assay in nude mice were compared, both assays were well correlated (r = 0.787, p less than 0.001). These results suggest that the antitumor activity of drugs can be evaluated faster, cheaper and easier by the subrenal capsule assay compared with the subcutaneous transplantation assay in nude mice. |