EFFECT OF INTERFERON-ALPHA, INTERFERON-GAMMA AND TUMOR-NECROSIS-FACTOR ON THE PROCOAGULANT ACTIVITY OF HUMAN CANCER-CELLS

Background. It is not known whether the different cytokines may influe nce the procoagulant activity of cancer cells; the purpose of this stu dy was to investigate the effect of interferon alpha, inteferon gamma and tumor necrosis factor on the procoagulation capacity of human canc er cells cultured <<in vitro>> or isolated from tumor tissues. Methods . <<In vitro>> cultured tumor cell lines were derived from a patient w ith malignant mesothelioma and a patient with lung adenocarcinoma. Cel ls isolated from 6 carcinomas of different origin were also investigat ed. The procoagulant activity of the cells before and after treatment with the cytokines was expressed as RBT U/10(5) cells or RVV U/10(5) c ells. Results. Short-term incubation of tumor cells cultured << in vit ro>> with cytokines did not modify their procoagulant activity; after longer incubation however, interferon alpha induced a significant incr ease in the procoagulant activity of mesothelioma cells, while interfe ron gamma induced and increase in the procoagulant activity of lung ad enocarcinoma cells. Furthermore, short-term incubation of cells isolat ed from tumor tissues with interferon gamma or tumor necrosis factor r esulted in a significant increase of procoagulant activity, while inte feron alpha had no effect. Conclusions. Altogether, these data demonst rate that the cytokines may influence the expression of the different procoagulant activities of tumor cells.