Abstract: | The antitumor activity of tumor necrosis factor (TNF) against various primarily cultured human cancer cells (32 cases) was investigated by the 51Cr cytotoxic release assay and the tumor stem cell assay. Over 50% sensitivity (the ratio to the cytotoxicity in L929 cells) was noted in 4 of 14 cases of gastric cancer (28.6%), 7 of 9 cases of leukemic cells (77.8%), and 1 case each of pancreatic carcinoma and ovarian cancer. Scarcely any sensitivity, however, was observed in 1 case of acute promyelocytic leukemia or in some of the gastric cancer cases. No correlation was observed between the histological type of the cancer and TNF sensitivity. The above results seem to confirm that TNF has significant antitumor activity against human cancer cells. |