title: p63 is required beside p53 for PERP-mediated apoptosis in uveal melanoma.
abstract: PERP (p53 apoptosis effector related to PMP-22), a transcriptional target of p53, is downregulated and contributes to the impairment of apoptosis in uveal melanoma (UM). Intriguingly, PERP is not induced in UM despite functional p53. p63, located on chromosome 3, which is characteristically altered in high-risk UM, can transactivate PERP. Here, we determine the functional role of p63 expression in the initiation of p53/PERP-mediated apoptosis in UM.
  
  
  
  PERP expression was monitored by quantitative PCR (qPCR) and immunoblotting in UM cell lines treated with DNA-damaging agents. The functional role of p63 was assessed by transient expression of p63-turbo GFP (p63-tGFP) in the apoptosis- resistant, 3q-deficient OCM-1 cells. Expression and localisation of p63, PERP and p53, and induction of apoptosis were characterised by qPCR, immunoblotting and live cell confocal microscopy.
  
  
  
  PERP expression was significantly downregulated in all UM cell lines. DNA-damaging treatments failed to induce apoptosis and activate PERP in OCM-1 cells, which displayed non-functional levels of p63. Expression of p63-tGFP induced apoptosis with marked increase in PERP expression and associated p53 accumulation.
  
  
  
  Lack of p63 contributes to reduced PERP levels and impaired p53-mediated apoptosis in UM. p63 expression is required for PERP-mediated apoptosis in UM.
authors: Department of Eye and Vision Science, Institute of Ageing and Chronic Disease, University of Liverpool, William Henry Duncan Building, 6 West Derby Street, Liverpool L7 8TX, UK.
authors: Raheela
authors: R
authors: Awais
authors: Systems Microscopy Centre, Faculty of Life Sciences, University of Manchester, Manchester M13 9PT, UK.
authors: David G
authors: DG
authors: Spiller
authors: Systems Microscopy Centre, Faculty of Life Sciences, University of Manchester, Manchester M13 9PT, UK.
authors: Michael R H
authors: MR
authors: White
authors: Department of Eye and Vision Science, Institute of Ageing and Chronic Disease, University of Liverpool, William Henry Duncan Building, 6 West Derby Street, Liverpool L7 8TX, UK.
authors: Luminita
authors: L
authors: Paraoan
mesh_terms: D017209:Apoptosis / Q000187:drug effects / Q000502:physiology* / Q000528:radiation effects; D045744:Cell Line, Tumor; D004249:DNA Damage; D015972:Gene Expression Regulation, Neoplastic; D006801:Humans; D015151:Immunoblotting; D008545:Melanoma / Q000235:genetics / Q000378:metabolism / Q000473:pathology*; D018613:Microscopy, Confocal; D060888:Real-Time Polymerase Chain Reaction; D011993:Recombinant Fusion Proteins / Q000378:metabolism; D053221:TNF-Related Apoptosis-Inducing Ligand / Q000494:pharmacology; D014157:Transcription Factors / Q000096:biosynthesis / Q000235:genetics / Q000502:physiology*; D015533:Transcriptional Activation; D025521:Tumor Suppressor Proteins / Q000096:biosynthesis / Q000235:genetics / Q000502:physiology*; D014466:Ultraviolet Rays; D014604:Uveal Neoplasms / Q000235:genetics / Q000378:metabolism / Q000473:pathology*
chemical_list: D011993:Recombinant Fusion Proteins; D053221:TNF-Related Apoptosis-Inducing Ligand; C115051:TP63 protein, human; D014157:Transcription Factors; D025521:Tumor Suppressor Proteins