Modifications of tumor-associated antigen expression on human lung cancer cells by hyperthermia and cytokine

The effect of hyperthermia and cytokine (IFN-gamma) in the expression of carcinoembryonic antigen (CEA) on the surface of cells was studied in vitro. The human lung cancer cell line, GLL-1, was used. The results demonstrate increase in CEA expression after hyperthermia. The magnitude of elevated CEA expression increased with increasing temperature (41-43 degrees C). Time-course study demonstrated that the peak CEA expression was 3 days after heating at 43 degrees C. The relative CEA expression was 1.3 at 1 day, 1.6 at 2 days, 1.9 at 3 days, 1.8 at 4 days, and 1.5 at 5 days, respectively. Hyperthermia plus IFN-gamma showed a synergistic effect in the expression of CEA. The four fold marked increase of CEA expression was detected. Furthermore, the pattern of time-course of CEA expression in hyperthermia combined with IFN-gamma was different from that in hyperthermia alone.