This study revealed that CTCs from CRC patients are characterized by hypermethylation of the SFRP2 promoter and exon 1 of VIM (Lyberopoulou et al., 2017), which are genes related to epithelial-to-mesenchymal transition (EMT) and CRC metastasis (Shirahata et al., 2009; Loboda et al., 2011; Vincent and Postovit, 2017). Here, SFRP2 is linked to colorectal carcinoma.