The complex pattern of regulation of UGT expression (reviewed in ref. 2) involves the production of many alternative variant isoforms presenting novel in-frame sequences, which are differentially expressed in oncogenic states.1,72 Furthermore, clinical parameters, including the type of cancer, aggressiveness or stage and cell-type-specific expression, all contribute to this variability in UGT expression. This evidence concerns the gene SLC35A2 and cancer.