THE PRESENCE OF TUMOR-NECROSIS-FACTOR-ALPHA AND ITS ANTIBODY IN THE SERA OF CACHEXIC PATIENTS WITH GASTROINTESTINAL CANCER

Although cancer cachexia has been shown to involve several cytokines, the tumor necrosis factor-alpha (TNF) has rarely been detected in such patients. In this study, sera from 21 patients with cancer cachexia w ere examined for the presence of TNF and the anti-TNF antibody using a n enzyme-linked immunosorbent assay (ELISA) and Western blotting, resp ectively. All of the patients had recurrent cancer and manifested the characteristics of progressive body weight loss. TNF was found in the sera of four patients (20%) at levels ranging from 10.4 to 53.1 pg/ml, while a positive reaction for the anti-TNF antibody was detected in t he sera from six patients (30%), two of whom showed both TNF and its a ntibody. Thus, either TNF or the anti-TNF antibody was present in the sera from 8 of 21 patients (40%). The results of this study indicate t hat TNF may be present in the circulation of at least 40% of cachexic patients, and suggest that it may be one of the main mediators of canc er-associated cachexia.