Gender, Cytidine Deaminase, and 5-Aza/Decitabine

WethankCiccolineandcolleaguesfortheirattentionandcommentsregarding"IncreasedCDAexpression/activityinmalescontributestodecreasedcytidineanaloghalf-lifeandlikely contributes to worse outcomes with 5-azacytidine ordecitabine therapy" (1). Ciccoline and colleagues have notfound a sex difference in CDA activity using high-perfor-mance liquid chromatography (HPLC)–based measure-ments of CDA enzyme activity in red blood cell (RBC)lysates(2).Inaddition touseofgemcitabine asasubstrate,which has a more than 10-fold higher K