Experimental Study on the Anti-tumor Mechanism of Interleukin-6 / 中国肿瘤生物治疗杂志

ABSTRACT

Segregated Kunming mice bearing S180 sarcoma were used as tumor models and treated with rhIL-6. The tumor regressed in most of the treated mice (8/10) in which there was no tumor growth when rechallenged with the same tumor cells, whereas 9/10 of controls died as the tumor progressed. Morphologically, in the treated group, the mice had enlarged spleen (4 times larger than that of control group)with hyperplastic white pulp consisted predominantly of activated lymphocytes. Cytotoxicity of spleen cells from IL-6 treated group to autologous tumor cells was higher than that of control group (907 ?318 387 ?144, P=0.003) and so did L929 cell line used as target (1145?164 186?251).We also set in vitro experiment using human PBL and human melanoma and colon carcinoma cell lines (A375,LS174). These cells were treated with IL-6 respectively and the cytotoxicity was assayed. Although PBL stimulated with IL-6 killed the LS174 more efficiently,the higher cytotoxicity to LS174 is because of the increased sensitivty of LS174 to the effector cells .On the contrary,IL-6 showed no effect on the A 375 cell line. It is assumed that this difference might result from the discrepancy of the recognition molecules existed on the cell surface between these two cell lines.