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 influence the procoagulant activity of cancer cells; the purpose of this study was to investigate the effect of interferon alpha, interferon gamma and tumor necrosis factor on the procoagulation capacity of human cancer cells cultured "in vitro" or isolated from tumor tissues. METHODS: "In vitro" cultured tumor cell lines were derived from a patient with malignant mesothelioma and a patient with lung adenocarcinoma. Cells isolated from 6 carcinomas of different origin were also investigated. 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) cells. RESULTS: Short-term incubation of tumor cells cultured "in vitro" with cytokines did not modify their procoagulant activity; after longer incubation however, interferon alpha induced a significant increase in the procoagulant activity of mesothelioma cells, while interferon gamma induced and increase in the procoagulant activity of lung adenocarcinoma cells. Furthermore, short-term incubation of cells isolated from tumor tissues with interferon gamma or tumor necrosis factor resulted in a significant increase of procoagulant activity, while interferon alpha had no effect. CONCLUSIONS: Altogether, these data demonstrate that the cytokines may influence the expression of the different procoagulant activities of tumor cells.