Retinoic acid increases sodium/iodide symporter mRNA levels in human thyroid cancer cell lines and suppresses expression of functional symporter in nontransformed FRTL-5 rat thyroid cells. - Schmutzler,C.; Winzer,R.; Meissner-Weigl,J.; Köhrle,J. (Biochem Biophys Res Commun, 1997)