NPM-ALK promotes FOXO3a retention in the cytoplasm in a manner dependent on FOXO3a phosphorylation. Cos-7 cells were transiently transfected with the EGFP-tagged FOXO3a construct (WT or AAA triple mutant) and were cotransfected with or without pcDNA-NPM-ALK. After 40 hours, EGFP signal was detected by fluorescence microscopy. Representative images are shown in panel A, and quantitation of the experiment is shown in panel B.