We examined DNA methylation levels of SFRP1, SFRP2, SFRP5, DKK2, DKK3, mir34b/c, RASSF1A, IGFBP7, CDKN2A, and MLH1 in cancerous glands and normal crypts isolated from cancer tissue and the surrounding normal mucosa. Here, DKK2 is linked to cancer.