Fig. 4.

Inhibition of autophagy by 3-methyladenine promoted TCF21 expression and cell apoptosis. a The expressions of ATG9, BECLIN-1, LC3-I and LC3-II and p62 were tested in H1299 with or without 3-methyladenine (3-MA) treatment by Western blotting. b The TCF21 promoter methylation levels in the H1299 cells with or without 3-MA treatment were detected by methylation-specific PCR. c The mRNA level of TCF21 in the H1299 cells with or without 3-MA treatment by quantitative real-time reverse transcription polymerase chain reaction (qRT-PCR). d Annexin V/propidium iodide double-staining assay was performed to detect the apoptosis levels of H1299 cells with or without 3-MA treatment. e Activity of autophagy by testing p62 was verified by inhibiting the activity of apoptosis using inhibitor Z-VAD-FMK (20 mM for 20 min). Data were presented as the means ± SD from three independent experiments with triple replicates per experiment. ** p < 0.01, indicate significant difference compared to untreated cells