Fig. 3

CREB5 promotes TOP1MT transcription in HNSCC. A RT-PCR was used to detect the effect of CREB5 on the expression of mitochondrial-related gene in HN4 and HN30 cells. B Immunoblotting was used to detect the effect of CREB5 on TOP1MT expression in HN4 and HN30 cells. C, D RT-PCR and immunoblotting were used to detect the effect of CREB5 knockdown on TOP1MT expression in HN4/DDP and HN30/DDP cells. E RT-PCR analysis of correlation of CREB5 expression with TOP1MT expression in HNSCC patients. F, G Immunoblotting was used to analyze the effect of TOP1MT on the mitochondrial apoptosis pathway in parent and cisplatin-resistant cells. H Schematic representation of TOP1MT promoter amplified by eight ChIP PCR primers. ChIP-PCR analysis of anti-CREB5- or IgG-immunoprecipitated TOP1MT promoter fragments extracted from HNSCC cells stably transfected with CREB5. I The luciferase deletion mutation vector of the predicted CREB5 target sequence (canonical motif: TGACG, non-canonical motif: TGGCG) in the TOP1MT gene. J Relative TOP1MT reporter activity in HN4 and HN30 cells co-transfected with CREB5 and luciferase reporter. K The effect of cisplatin resistance on TOP1MT reporter luciferase activity in HN4 and HN30 cells. *p < 0.05; **p < 0.01; ***p < 0.001; ****p < 0.0001