SFRP1 and colorectal carcinoma: Examples of genes methylated early and involved in the initiation of CRC include SLC5A8, MINT1, MINT31, SFRP1, SFRP2, CDH13, CRBP1, RUNX3, p14ARF, HLTF, ITGA4, CDKN2A (p16), CDH1 and ESR1 [5].