Fig. 6. PCBP2 and TRIB2 maintain cell viability via GPX4 under OS.
a Spheroid formation by the Bel-7402 and SMMC-7721 cells with or without TRIB2 knocked out, in the presence or absence of overexpressed PCBP2 (n = 3); Scale bar = 30 µm. Data were analyzed by one-way ANOVA and expressed as mean ± SD. ***P < 0.001; ****P < 0.0001. b Tumor growth in athymic mice inoculated with Bel-7402 cells with or without TRIB2 knocked out in the presence or absence of overexpressed PCBP2 (n = 5/group); Scale bar = 4 mm. The data were analyzed by Student’s t-test and expressed as mean ± SD. ***P < 0.001; ****P < 0.0001. c–h Inhibition of GPX4 diminished the ability of TRIB2 and PCBP2 to protect cells against OS. Bel-7402 cells transfected with Dox-inducible shRNA targeting GPX4 (iGPX4sh1 (c, f); iGPX4sh2 (d, g)) were pretreated with or without Dox (700 ng/ml, 24 h) (c, d, f, g). Bel-7402 cells were also pretreated with or without RSL3 (5 µM) for 5 h (e, h). Then, the cells were exposed to the indicated concentration of t-BuOOH (c–e) or diquat (f–h) for another 24 h. Cell viability was determined and calculated as described in the “Materials and methods” section (n = 3). The data were analyzed by one-way ANOVA and expressed as mean ± SD. **P < 0.01; ***P < 0.001; ****P < 0.0001. NS non-significance.