title: A3 adenosine receptor mediates apoptosis in in vitro RCC4-VHL human renal cancer cells by up-regulating AMID expression.
abstract: OBJECTIVE
  Accumulating studies have shown that extracellular adenosine induces apoptosis in various cancer cells via diverse signaling pathways. We sought to understand adenosine induced apoptosis in human renal cancer cells and the underlying pathway.
  
  
  METHODS
  RCC4-VHL (European Collection of Animal Cell Cultures, Salisbury, United Kingdom), ACHN (Cell Resource Center for Biomedical Research, Institute of Development, Aging and Cancer, Tohuku University, Aoba-ku, Sendai, Japan) and 786-O (ATCC®) human renal cancer cells were cultured. MTT assay, TUNEL staining, reverse transcriptase-polymerase chain reaction and Western blot were done in cells untransfected and transfected with siRNA silencing the A(3) adenosine receptor targeted gene or the AMID targeted gene.
  
  
  RESULTS
  Adenosine induced apoptosis in all cell types used in a concentration (1 to 10 mM) dependent manner. A similar effect was obtained with the A(3) adenosine receptor agonist 2-Cl-IB-MECA. Adenosine induced RCC4-VHL cell death was inhibited by the A(3) adenosine receptor inhibitor MRS1191 or by knocking down A(3) adenosine receptor or AMID. Adenosine up-regulated the expression of AMID mRNA and protein in RCC4-VHL cells, which was suppressed by A(3) adenosine receptor knockdown. Moreover, adenosine promoted AMID translocation from cytosol to nucleus.
  
  
  CONCLUSIONS
  Adenosine induces RCC4-VHL cell apoptosis by up-regulating AMID expression and accumulating AMID in the nucleus via A(3) adenosine receptor.
authors.affiliation: Laboratory of Cell and Gene Therapy, Institute for Advanced Medical Sciences and Division of Bioinformation, Department of Physiology, Hyogo College of Medicine, Mukogawa-cho, Nishinomiya, Japan.
authors.forename: Hisao
authors.initials: H
authors.lastname: Nagaya
authors.forename: Akinobu
authors.initials: A
authors.lastname: Gotoh
authors.forename: Takeshi
authors.initials: T
authors.lastname: Kanno
authors.forename: Tomoyuki
authors.initials: T
authors.lastname: Nishizaki
mesh_terms: D017209:Apoptosis / Q000502:physiology*; D051017:Apoptosis Regulatory Proteins / Q000096:biosynthesis*; D002292:Carcinoma, Renal Cell / Q000473:pathology; D045744:Cell Line, Tumor; D006801:Humans; D007680:Kidney Neoplasms / Q000473:pathology; D024101:Mitochondrial Proteins / Q000096:biosynthesis*; D043684:Receptor, Adenosine A3 / Q000502:physiology*; D015854:Up-Regulation; D051794:Von Hippel-Lindau Tumor Suppressor Protein
chemical_list: C462504:ferroptosis suppressor protein 1, human; D051017:Apoptosis Regulatory Proteins; D024101:Mitochondrial Proteins; D043684:Receptor, Adenosine A3; D051794:Von Hippel-Lindau Tumor Suppressor Protein; C497446:VHL protein, human