Fig. 4

SERPINB5 prevents X-ray radiation–induced NPC cell apoptosis. a Flow cytometry analysis of Annexin V and PI staining in HONE1 cells with TRIM21 GOF or LOF after X-ray radiation. Annexin⁺PI⁻ cells were evaluated and quantified. b, c Quantification of apoptotic HONE1 b and 5-8F c cells. d Absorbance intensity of SERPINB5 GOF (top) and LOF (bottom) tumor cells and their counterpart controls in mice (n = 5 for each group). The tumors were evaluated 2 and 3 weeks, respectively, after implantation, and the mice received radiotherapy (2 Gy daily and a total of 12 Gy) after 2 weeks. e, f Absorbance intensity analysis of the tumors in mice. g GFP expression in HONE1 cells with SERPINB5-V2A-GFP overexpression or TRIM21 knockout. h Flow cytometry analysis of GFP⁺ cell percentages in HONE1 and 5-8F cells. *P < 0.05, **P < 0.01, ***P < 0.001