Fig. 3
IL-6 expressing CD133+ cells (sc) were more radioresistant than IL-6 knocked down (IL-6si) cells. a Confirmation of IL-6 knockdown in IL-6si cells. IL-6 mRNA levels in A549IL-6si/sc and H157IL-6si/sc cell lines were analyzed by qPCR analyses and relative mRNA expressions were shown. b IL-6 secreted levels in CD133+ and CD133- cells of A549IL-6si/sc and H157IL-6si/sc cell lines. Supernatants were collected from CD133- and CD133+ cells of A549IL-6si/sc and H157IL-6si/sc cell lines and secreted IL-6 levels were analyzed by ELISA kit. c IL-6 IF staining. CD133+ cells of A549IL-6si/sc pairs were plated and IF staining was performed using anti-IL-6 Ab. d Clonogenic survival curves showed IL-6 expressing (sc) CD133+ cells (sc) were more radiation resistant than IL-6 knocked down (IL-6si) CD133+ cells. CD133+ cells of A549IL-6si/sc and H157IL-6si/sc pairs were exposed to different doses of radiation. Nine days later, cell survival was analyzed by clonogenic assay. Upper panel, result of CD133+ cells of A549IL-6si/sc pair; lower panel, result of CD133+ cells of H157IL-6si/sc pair (40-50 % plating efficiencies). c Sphere formation was higher in IL-6 expressing cells. CD133+ cells of A549IL-6si/sc and H157IL-6si/sc pairs were irradiated with 6 gamma rays. Ten days after irradiation, sphere formation assays were performed. Spheres having diameter greater than 50 μm were counted. d Higher number of Ki67 positive cells in IL-6 expressing cultures in IF staining. CD133+ cells of A549IL-6si/sc pair were irradiated (6 Gy). Two days after irradiation, IF staining was performed using anti-Ki67 Ab. *p < 0.05, **p < 0.01, ***p < 0.001. e Sphere formation was higher in IL-6 expressing cells. CD133+ cells of A549-6si/sc and H157IL-6si/sc pairs were irradiated with 6Gy gamma rays. Ten days after irradiation, sphere formation assays were performed. Spheres having a diameter greater than 50um were counted. f Higher number of Ki67 positive cells in IL-6 expressing cultures in IF staining. CD133+ cells of A549IL-6si/sc pair were irradiated (6Gy). Two days after irradiation, IF staining was performed using anti-Ki67 Ab. g IL-6 ELISA tests of CD133- and CD133+ cells of A549IL-6si/sc and H157IL-6si/sc pair. *p < 0.05, **p < 0.01, ***p < 0.001