Fig. 1

TERRA expression increased in patients with IPF and cell model. a AEC-II and mitochondria were observed in normal cells under TEM. Mitochondria were marked by arrows. b Apoptotic AEC-II and mitochondria observed in patients with IPF under TEM. c TERRA expression increased in the peripheral blood mononuclear cells of patients with IPF, as indicated by qRT-PCR results. The data of TERRA expression are normalized to one in every healthy person. The data in each corresponding patient are standardized by each corresponding healthy person. d Forced vital capacity, expressed as FVC%, significantly decreases with the TERRA expression in patients with IPF. r = −0.6915, P = 0.0002. TERRA expression was calculated by using 2^−△△Ct. e TERRA expression increased with prolonged H₂O₂ treatment in the cell model. A549 cells were treated with 120 μM of H₂O₂ for 0, 3, 6, 12, and 24 h. f TERRA expression levels in the animal model also significantly increased. g The qRT-PCR data showed that siRNAs-TERRA was effectively interfered with TERRA expression in A549 cells. h siRNA-TERRA1 and siRNA-TERRA2 promoted the proliferation of H₂O₂-treated A549 cells. After transfection with siRNA-TERRA1, siRNA-TERRA2, or siRNA-negative control for 48 h, cells were co-treated with 120 μM of H₂O₂ for 12 h. i After the cells were transfected with siRNA-TERRA1, siRNA-TERRA2, or siRNA-negative control for 3 h, cells were co-treated with 120 μM of H₂O₂ for 3 h. Then, A549 cell growth curves were analyzed using xCELLigence real-time cell analyzer for 80 h. j The analytical data of the cell growth curves showed TERRA silencing can promote cell growth. Each bar represents mean ± standard deviation (SD), n = 6. ^* P < 0.05 and ^** P < 0.01 compared with the normal control group or sham group. ^# P < 0.05 and ^## P < 0.01 compared with the H₂O₂+ siRNA-TERRA negative control group. ^▲▲ P < 0.01 compared with the normal + siRNA-TERRA negative control group