SFRP1 and colorectal carcinoma: Thus, assessment of DNA methylation levels of genes expressed in normal cryptal cells, including SFRP1, SFRP2, SFRP5, DKK2, DKK3, mir34b/c, RASSF1A, IGFBP7, CDKN2A, and MLH1 might be useful in early detection or risk prediction of CRC.