Inhibitory effect of tumor necrosis serum on the metastasis of B-16 mouse melanoma cells.

The inhibitory effect of tumor necrosis serum (TNS) on the artificial metastasis of B-16 melanoma cells and the spontaneous metastasis of Lewis lung carcinoma cells was investigated. The results obtained were as follows: 1) When tumor necrosis serum (TNS) was administered either 20 min or 2 days after injection of B-16 melanoma cells, a very strong inhibitory effect (99%) relative to the control was noted. 2) TNS showed a 60% inhibitory effect on spontaneous metastasis, and the weight of the original tumor regressed by 60%. 3) No histological changes in normal tissues were observed microscopically following TNS injection. The above results confirm that TNS is extremely effective in preventing metastasis.