IL6 and ovarian cancer: To investigate the effect of minocycline on IL-6 expression in ovarian cancer cells, immunofluorescent staining was performed after 24 h treatment of OVCAR-3 (with low IL-6 expression), SKOV-3 (with medium IL-6 expression), and CAOV-3 (with high IL-6 expression) cell lines with minocycline (100 μM).