Fig. 7

Targeting the EMT stage for inhibition of PF by HSP27 inhibitor. A Illustration of the differences in HSP27 cross-linker administration periods. All mice were intraperitoneally (i.p.) administrated J2 (15 mg/kg); IR + J2 I group: J2 treatment until 12 weeks after 75 Gy IR exposure; IR + J2 II group: J2 treatment from 4 to 12 weeks after IR; IR + J2 III group: J2 treatment from 6 to 12 weeks after IR. On the 12th week, the lung tissues of mice from each group were harvested. B Lungs were photographed after complete fixation (top) and stained with H&E (2nd from the top), Sirius red (2nd from the bottom), or Masson’s trichrome (bottom). The graph shows quantification of the stained region. n ≥ 3, mean ± SD; ^***P < 0.001 vs. control; ^#P < 0.05, ^##P < 0.01 and ^###P < 0.001 vs. IR only. C Immunohistochemistry of HSP25 (top and middle; 40 and 400 ×) and pHSP25 (Ser 86) (bottom; 200 ×) in mouse lung tissues. The graph shows the quantification of positive cells. n ≥ 3, mean ± SD; ^***P < 0.001 vs. control; ^#P < 0.05 vs. IR only. D HSP27 (green) was co-stained with Twist (red) and α-SMA (violet). Magnification, 200 × . Scale bar, 20 μm, (n ≥ 3). ^***P < 0.001 vs. control; ^#P < 0.05, ^##P < 0.01, and ^###P < 0.001 vs. IR only. E qRT-PCR of L132 cells transfected with either siControl or siSmurf2. Cell lysates 12 h after 10 Gy IR with or without J2 (10 μM). gapdh mRNA was used for normalization. (n ≥ 4, mean ± SD) ^*P < 0.05, ^**P < 0.01, and ^***P < 0.001 vs. control; ^#P < 0.05 and ^###P < 0.001 vs. IR alone; ^†P < 0.05 and ^†††P < 0.001 vs. siControl-IR