Interferon alfa activates a lytic mechanism in ovarian and cervical carcinoma cells.

Abstract

Our purpose was to examine the in vitro cytolytic potential of interferon alfa for human cervical and ovarian carcinoma cell lines. The lytic potential of interferon alfa alone and in the presence the protein synthesis inhibitors actinomycin D and emetine was determined in the human cervical carcinoma cell lines ME-180, MS751, SiHa, HT-3, and C-33A and the ovarian carcinoma cell lines Caov-3, NIH:OVCAR-3, SK-OV-3 carcinoma cell lines by means of an 18-hour chromium 51 release assay. Exposure of these cell lines to interferon alfa alone did not result in lysis. Similarly, when cells were simultaneously exposed to interferon alfa and either actinomycin D or emetine there was no additional increase in lysis above that seen with actinomycin D or emetine alone. Pretreatment of cells with interferon alfa (10(3), 10(4), or 10(5) U/ml) followed by protein synthesis inhibition by actinomycin D or emetine resulted in a synergistic increase in lysis. The ability to reveal the lytic potential of interferon alfa when protein synthesis is subsequently inhibited could have practical applications for the treatment of gynecologic malignancies.