ECRG4 promoter methylation and mRNA expression in primary colorectal carcinoma samples. a) COBRA analysis of ECRG4 methylation in colorectal carcinoma and normal colon tissue samples. Arrows point to restriction fragments indicating a methylated sequence. b) Box plots of methylation percentages of selected colorectal carcinomas and normal colon tissue as determined by Epitect bisulfite sequencing analysis. unmeth = unmethylated; meth = methylated c) Box plots of relative ECRG4 mRNA expression as determined by semiquantitative RT-PCR in colorectal carcinomas relative to normal colon tissue. Note a significantly lower expression in tumor tissue (p = 0.0018). NT = normal colon tissue; CC = colorectal carcinoma.