From a screen of eight thyroid cancer cell lines, we recently reported that there was no common thyroid CSC marker among 11 candidate markers [CD13, 15 (stage-specific embryonic antigen 1, SSEA-1), 24, 44, 44v, 90, 117, 133, 166, and 326 (epithelial cell adhesion molecule, EpCAM), and ALDH] (8). Here, FUT4 is linked to thyroid cancer.