EXPERIMENTAL-STUDY OF THE EFFECT OF IL-6 ON CANCER CACHEXIA

Several cytokines, including IL-1, TNF, LIF and IL-6 have recently bee n proposed as cachexia inducers. We experimentally examined the partic ipation of cytokines, particularly, IL-6, in cancer cachexia using the human digestive cancer cell lines MKN 28, MKN 45, MKN 74, Kato-III, O CUM-2M (gastric cancer), SW1990, Panc-1 (pancreatic cancer), and OCUG (gallbladder cancer). A high level of IL-6 was detected in the OCUG cu lture medium. Nude mice bearing OCUG tumor had reduced body weight eve n when the tumor was relatively small. Loss of both muscle and adipose tissue, anemia, hypoglycemia, and a high serum level of human IL-6 we re observed in these mice. However, body weight recovered rapidly to t he level of that of nontumor-bearing mice after resection of OCUG tumo r. Antihuman IL-6 but not anti-murine IL-6 receptor antibodies signifi cantly suppressed the development of cachexia as measured by various i ndicators of cachexia including loss of both muscle and adipose tissue , anemia and hypoglycemia, as well as weight loss. These results sugge st that OCUG-bearing mice exhibited cancer cachexia mediated by IL-6, and that of OCUG cell line might be useful as a human digestive cancer cachexia model.