Fig. 1

Conditioned medium derived from the irradiated HCC cells enhanced normal hepatocyte injury. a Conditioned media were collected from irradiated SMMC7721 cells (with exposure to 2, 4, or 6 Gray) and non-irradiated SMMC7721 cells after incubated for 24 h. Conditioned medium from each of the four groups was mixed with normal medium in different proportion (1:4, 1:2, 1:1, 2:1, and 4:1). Normal hepatocytes L02 were incubated with these mixtures for 48 h. The viability of L02 cells was examined by CCK8 assay. b Viability of L02 cells was examined by the CCK8 assay at different time points after incubation with 7721-NR-CM and 7721-R-CM. Data presented were fold-change of 7721-R-CM group compared with 7721-NR-CM group ± SD from three independent experiments. **P < 0.01. c, d L02 cells were cultured in different medium as indicated, and apoptotic cells were detected by flow cytometry after 24 h. e The protein levels of Fas, ALB, Bcl-2, Bid, Bax, and cleaved caspase3 were determined by Western Blot. GAPDH was used as a loading control. f Changes of AST, ALT, ALB, SOD2, and MDA levels in culture supernatant of L02 cells after incubated with 7721-R-CM and 7721-NR-CM alone or combined with Fas-Fc. *P < 0.05, **P < 0.01