Thus, the results revealed a strong correlation between DLEC1 transcriptional silencing and its promoter methylation in virtually all CRC and gastric cancer cell lines examined, except for one CRC cell line LS180, which has both methylated and unmethylated promoter alleles but DLEC1 expression is totally silenced, indicating that other mechanisms such as histone modification also could not be excluded. The gene discussed is DLEC1; the disease is gastric cancer.