Imiquimod Inhibits Proliferation of Serous Epithelial Ovarian Cancer Cells In Vitro: A Preliminary Study

Imiquimod, known as positive immune response modifier and stimulates local cytokine induction, has been used in therapy of genital warts via increasing local interferon and reducing human papillomavirus production. We aimed to investigate whether imiquimod has any effect on the proliferation of serous epithelial ovarian cancer cells in vitro. The study was designed in two stages. The first stage was designed to evaluate co-culturing of serous epithelial ovarian cancer cells with the drug imiquimod versus cancer cells cultured with no drug. The second stage of the study was initiated with primary ovarian cancer cell culture growth. Imiquimod was applied in increasing concentrations to flasks full of each kind of cells. Also, histomorphometrical evaluation was made using an unbiased counting frame. Treatment of the primary cancer cell cultures with imiquimod in concentrations of 2.5 μg/ml and 5.0 μg/ml did not result in a significant effect on cell proliferation and the cell proliferation continued. Cell proliferation stopped and the cells detached at concentrations of 7.5 μg/ml, especially 10.0 μg/ml, 12.5 μg/ml, and 25.0 μg/ml, within 2–3 days after exposure to the drug. The anti-proliferative effect of imiquimod reached a maximum level at a concentration of 12.5 μg/ml. Imiquimod has a dose-dependent anti-proliferative impact on serous epithelial ovarian cancer cells in vitro.