title: LYRIC/AEG-1 overexpression modulates BCCIPalpha protein levels in prostate tumor cells.
abstract: LYRIC/AEG-1 is a unique protein that has been shown to promote tumor cell migration and invasion through activation of the transcription factor NF-kappaB. We performed yeast two-hybrid screening to detect LYRIC/AEG-1 associated proteins, and identified BCCIP, a CDKN1A and BRCA2-associated protein involved in cell cycle regulation and DNA repair. Here, we demonstrate association between LYRIC/AEG-1 and BCCIP in mammalian cells, and define the region of interaction. Co-expression of the two proteins resulted in decreased levels of BCCIPalpha, an effect partially abrogated by proteasome inhibition. A truncated LYRIC/AEG-1 construct lacking the interaction region did not alter BCCIPalpha protein levels. Coincidentally, it was observed that overexpression of BCCIPalpha in DU145 prostate tumor cells induced an apparent neuroendocrine differentiation. In summary, our data suggest LYRIC/AEG-1 is a negative regulator of BCCIPalpha, promoting proteasomal degradation either through direct interaction, or potentially through an indirect mechanism involving downstream effects of the NF-kappaB signaling pathway.
authors.affiliation: Department of Medicine, Division of Hematology/Oncology, Rhode Island Hospital, and The Alpert Medical School, Brown University, 593 Eddy Street, Geo. 362, Providence RI 02903, USA.
authors.forename: S C
authors.initials: SC
authors.lastname: Ash
authors.forename: D Q
authors.initials: DQ
authors.lastname: Yang
authors.forename: D E
authors.initials: DE
authors.lastname: Britt
mesh_terms: D002135:Calcium-Binding Proteins / Q000235:genetics / Q000378:metabolism*; D015815:Cell Adhesion Molecules / Q000235:genetics / Q000378:metabolism*; D018797:Cell Cycle Proteins / Q000235:genetics / Q000378:metabolism*; D002454:Cell Differentiation; D045744:Cell Line, Tumor; D006801:Humans; D008297:Male; D008565:Membrane Proteins / Q000235:genetics / Q000378:metabolism*; D016328:NF-kappa B / Q000378:metabolism; D016501:Neurites / Q000378:metabolism / Q000502:physiology; D009490:Neurosecretory Systems / Q000166:cytology / Q000378:metabolism; D009687:Nuclear Proteins / Q000235:genetics / Q000378:metabolism*; D011471:Prostatic Neoplasms / Q000378:metabolism*; D046988:Proteasome Endopeptidase Complex / Q000378:metabolism; D061988:Proteasome Inhibitors; D016601:RNA-Binding Proteins; D020798:Two-Hybrid System Techniques
chemical_list: C415366:BCCIP protein, human; D002135:Calcium-Binding Proteins; D015815:Cell Adhesion Molecules; D018797:Cell Cycle Proteins; C483039:MTDH protein, human; D008565:Membrane Proteins; D016328:NF-kappa B; D009687:Nuclear Proteins; D061988:Proteasome Inhibitors; D016601:RNA-Binding Proteins; D046988:Proteasome Endopeptidase Complex