title: Overexpression of PML induced apoptosis in bladder cancer cell by caspase dependent pathway.
abstract: The promyelocytic leukemia gene (PML) encodes a growth/tumor suppressor protein that is essential for the induction of apoptosis in response to various apoptotic signals. The mechanism by which PML plays a role in the regulation of cell death is still unknown. Our previous study demonstrated that overexpression of PML suppress the growth of bladder cancer cells by inducing apoptosis and cell cycle arrest. To further elucidate the mechanism of PML induced apoptosis in bladder cancer, we constructed a PML inducible stable cell line. We found that the increased expression of PML significantly inhibit the growth of the UM-UC-2/PML clone cells and present apparent massive apoptosis in 24 h post-induction, while the UM-UC-2/PMEP4 cells are not. We also examined the effect of PML on the cell cycle distribution in UM-UC-2 cells. We showed overexpression of PML cause a cell cycle arrest in G1 phase. In additional, increased expression of PML in bladder cancer UM-UC-2 cells reduce Survivin expression and up regulated Caspase-3, and cleaved PARP expression, these suggested that PML might regulate apoptosis through Caspase dependent pathways. Our results demonstrate a novel mechanism of PML-induced apoptosis by down-regulation of Survivin and activation of Caspase dependent pathway.
authors.affiliation: Institute of Urology, No. 1 Hospital, Xi'an Jiaotong University, Shaanxi 710061, China.
authors.forename: Lei
authors.initials: L
authors.lastname: Li
authors.forename: Dalin
authors.initials: D
authors.lastname: He
authors.forename: Hui
authors.initials: H
authors.lastname: He
authors.forename: Xinyang
authors.initials: X
authors.lastname: Wang
authors.forename: Linlin
authors.initials: L
authors.lastname: Zhang
authors.forename: Yong
authors.initials: Y
authors.lastname: Luo
authors.forename: Xunyi
authors.initials: X
authors.lastname: Nan
mesh_terms: D017209:Apoptosis / Q000235:genetics; D053148:Caspase 3; D020169:Caspases / Q000378:metabolism*; D045744:Cell Line, Tumor; D049109:Cell Proliferation; D015536:Down-Regulation; D004789:Enzyme Activation; D016193:G1 Phase; D006801:Humans; D020287:In Situ Nick-End Labeling; D051034:Inhibitor of Apoptosis Proteins; D008869:Microtubule-Associated Proteins / Q000235:genetics / Q000378:metabolism; D009363:Neoplasm Proteins / Q000096:biosynthesis / Q000235:genetics / Q000378:metabolism*; D009687:Nuclear Proteins / Q000096:biosynthesis / Q000235:genetics / Q000378:metabolism*; D011065:Poly(ADP-ribose) Polymerases / Q000235:genetics / Q000378:metabolism; D000071156:Promyelocytic Leukemia Protein; D000077022:Survivin; D014157:Transcription Factors / Q000096:biosynthesis / Q000235:genetics / Q000378:metabolism*; D014162:Transfection; D025521:Tumor Suppressor Proteins / Q000096:biosynthesis / Q000235:genetics / Q000378:metabolism*; D001749:Urinary Bladder Neoplasms / Q000235:genetics / Q000378:metabolism*
chemical_list: C107489:BIRC5 protein, human; D051034:Inhibitor of Apoptosis Proteins; D008869:Microtubule-Associated Proteins; D009363:Neoplasm Proteins; D009687:Nuclear Proteins; D000071156:Promyelocytic Leukemia Protein; D000077022:Survivin; D014157:Transcription Factors; D025521:Tumor Suppressor Proteins; C070576:PML protein, human; D011065:Poly(ADP-ribose) Polymerases; C505407:CASP3 protein, human; D053148:Caspase 3; D020169:Caspases