Fig. 2

Methylation and expression levels of CPEB1 are negatively correlated with one another in both primary CRCs and CRC cell lines. a Expression of CPEB1 in CRCs and para-tumour tissues from TCGA database; FPKM, fragments per kilobase of exon model per million mapped fragments. b The significant negative correlation between CPEB1 methylation and expression from the TCGA database. CPEB1 expression is shown on the y-axis, whilst the average methylation level (β value) of the CPEB1 promoter is shown on the x-axis. c CPEB1 expression in CRC tumours and para-tumour tissues detected by real-time qPCR in our validation cohort. d The significant negative correlation between CPEB1 methylation and expression in our validation cohort. e, f Average methylation levels of all CpG sites in the targeted region of CPEB1 in both SW480 and HCT116 cells in the presence or absence of 5-aza-2′-deoxycytidine (DAC). Four replicate experiments were performed with each cell line. g Expression of CPEB1 in SW480 and HCT116 cells in the presence or absence of DAC. h CPEB1 protein detected in SW480 and HCT116 cells in the presence or absence of DAC. CPEB1 protein density normalised to the GAPDH internal control is shown on the y-axis. Data are presented as the mean ± SD; **P < 0.01; ***P < 0.001