title: Transcriptional repression of CDKN2D by PML/RARα contributes to the altered proliferation and differentiation block of acute promyelocytic leukemia cells.
abstract: Cell proliferation and differentiation are highly coordinated processes. These two processes are disrupted during leukemogenesis, resulting in differentiation block and uncontrolled proliferation in leukemia. To understand the mechanisms disrupting the coordination between the two processes in acute promyelocytic leukemia (APL), we investigated the regulatory mechanism of the negative cell cycle regulator CDKN2D by the promyelocytic leukemia/retinoic acid receptor α (PML/RARα) fusion protein and the role of CDKN2D in cell differentiation and proliferation. We found that CDKN2D expression in APL cells was significantly lower than that in normal promyelocytes. By chromatin immunoprecipitation and luciferase reporter assays, we showed that PML/RARα directly bound to and inhibited the transactivation of the CDKN2D promoter. Further evidence by the truncated and mutated CDKN2D promoters revealed that the everted repeat 8 (ER8) motif on the promoter was the binding site of PML/RARα. Forced expression of CDKN2D induced G0/G1 phase arrest and partial granulocytic differentiation in APL-derived NB4 cells, suggesting the function of CDKN2D in regulating both cell proliferation and granulocytic differentiation. Furthermore, all-trans retinoic acid (ATRA) significantly induced CDKN2D expression in APL cells and knockdown of CDKN2D expression during ATRA treatment partially blocked the ATRA-induced differentiation and cell cycle arrest. Collectively, our data indicate that CDKN2D repression by PML/RARα disrupts both cell proliferation and differentiation in the pathogenesis of APL, and induced expression of CDKN2D by ATRA alleviates the disruption of both processes to ensure treatment efficiency. This study provides a mechanism for coupling proliferation and differentiation in leukemic cells through the action of CDKN2D.
authors.affiliation: State Key Laboratory of Medical Genomics and Shanghai Institute of Hematology, Rui Jin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, 200025, China.
authors.forename: Y
authors.initials: Y
authors.lastname: Wang
authors.affiliation: 1] State Key Laboratory of Medical Genomics and Shanghai Institute of Hematology, Rui Jin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, 200025, China [2] Institute of Health Sciences, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai, 200025, China [3] Sino-French Research Center for Life Sciences and Genomics, Rui Jin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, 200025, China.
authors.forename: W
authors.initials: W
authors.lastname: Jin
authors.affiliation: State Key Laboratory of Medical Genomics and Shanghai Institute of Hematology, Rui Jin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, 200025, China.
authors.forename: X
authors.initials: X
authors.lastname: Jia
authors.affiliation: School of Life Sciences/Center for Computational Systems Biology, Fudan University, Shanghai, 200433, China.
authors.forename: R
authors.initials: R
authors.lastname: Luo
authors.affiliation: State Key Laboratory of Medical Genomics and Shanghai Institute of Hematology, Rui Jin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, 200025, China.
authors.forename: Y
authors.initials: Y
authors.lastname: Tan
authors.affiliation: State Key Laboratory of Medical Genomics and Shanghai Institute of Hematology, Rui Jin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, 200025, China.
authors.forename: X
authors.initials: X
authors.lastname: Zhu
authors.affiliation: State Key Laboratory of Medical Genomics and Shanghai Institute of Hematology, Rui Jin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, 200025, China.
authors.forename: X
authors.initials: X
authors.lastname: Yang
authors.affiliation: State Key Laboratory of Medical Genomics and Shanghai Institute of Hematology, Rui Jin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, 200025, China.
authors.forename: X
authors.initials: X
authors.lastname: Wang
authors.affiliation: 1] State Key Laboratory of Medical Genomics and Shanghai Institute of Hematology, Rui Jin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, 200025, China [2] Institute of Health Sciences, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai, 200025, China [3] Sino-French Research Center for Life Sciences and Genomics, Rui Jin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, 200025, China.
authors.forename: K
authors.initials: K
authors.lastname: Wang
mesh_terms: D001665:Binding Sites; D059447:Cell Cycle Checkpoints; D002454:Cell Differentiation; D049109:Cell Proliferation; D050764:Cyclin-Dependent Kinase Inhibitor p19 / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism; D015536:Down-Regulation; D006801:Humans; D015473:Leukemia, Promyelocytic, Acute / Q000235:genetics / Q000378:metabolism / Q000503:physiopathology*; D015514:Oncogene Proteins, Fusion / Q000235:genetics / Q000378:metabolism*; D011401:Promoter Regions, Genetic
chemical_list: C493974:CDKN2D protein, human; D050764:Cyclin-Dependent Kinase Inhibitor p19; D015514:Oncogene Proteins, Fusion; C093476:promyelocytic leukemia-retinoic acid receptor alpha fusion oncoprotein