Figure 2 (A) JHU-011 cells, FaDu cells were divided into 5 groups according to the dose gradient (0 Gy, 2.5 Gy, 5 Gy, 10 Gy, 20 Gy), and γ-irradiation was carried out at room temperature. After irradiation, the cells were cultured for 12 h, and then the RT-PCR was performed to detect the transcription level of PSMB8. The dose of 10 Gy showed the most significant induction effect on all 3 types of the cells (** P<0.01). (B) Western blot of PSMB8 in FaDu cells and JHU-011 cells. Lanes: 1, FaDu cells without irradiation; 2, FaDu cells with irradiation; 3, JHU-011 cells without irradiation; 4, JHU-011 cells with irradiation. (C) The dose of 10 Gy was used to irradiate the JHU-011 cells and FaDu cells, and the relative ratio between isoforms E1 and E2 was detected by RT-PCR. The percentage of E2 was significantly upregulated by irradiation in FaDu cells (** P<0.01) and JHU-011 cells (** P<0.01). Each group included 3 independent repeats. Quantitative data are expressed as the mean±standard deviation (SD). (D) Plasmid pLKO.1-TRC contained the insertion site of the shRNA, located between the U6 promoter and cPPT, which originally was a stuffer of approximately 1.9 kb long. After digestion with AgeI and EcoRI, the designed double-stranded shRNA oligos (c-Abl-shRNA and c-Abl-Arg) were inserted into the gap between the AgeI and EcoRI sites to replace the stuffer, yielding the vector.