title: Selection of housekeeping genes for gene expression studies in a rat model of irinotecan-induced mucositis.
abstract: OBJECTIVE
  Mucositis is the term used to describe damage caused by chemotherapy to mucous membranes of the alimentary tract. RT-PCR has recently been utilised to determine the molecular events that occur in mucositis. As this method relies on the use of a validated endogenous control, this study aims to validate commonly used housekeeping genes in an irinotecan-induced mucositis model.
  
  
  METHODS
  Rats were administered irinotecan and sacrificed at different time points, in particular 1, 24, 72 and 144 h following treatment. Histopathological damage was assessed by haematoxylin and eosin staining. RT-PCR was used to evaluate the expression of 11 housekeeping genes. Expression stability was determined by the Normfinder program. Matrix metalloproteinase 2 was used as a target gene to validate the appropriateness of the top-ranking housekeeping gene.
  
  
  RESULTS
  For normalisation to multiple housekeeping genes, the most stable combination across all time points in the jejunum was Ywhaz/UBC and in the colon UBC/β-actin. SDHA and GAPDH were the most variable genes in the jejunum and colon where they were 4.4 and 3.2 fold upregulated following irinotecan, respectively.
  
  
  CONCLUSIONS
  For normalisation of irinotecan-induced mucositis gene expression studies, a combination of Ywhaz/UBC and UBC/β-actin should be used in the jejunum and colon, respectively. UBC is the most favourable if restricted to a single housekeeping gene across all time points.
authors.affiliation: Department of Medicine, University of Adelaide, Adelaide, S.A., Australia. noor.al-dasooqi@adelaide.edu.au
authors.forename: Noor
authors.initials: N
authors.lastname: Al-Dasooqi
authors.forename: Joanne M
authors.initials: JM
authors.lastname: Bowen
authors.forename: Rachel J
authors.initials: RJ
authors.lastname: Gibson
authors.forename: Richard M
authors.initials: RM
authors.lastname: Logan
authors.forename: Andrea M
authors.initials: AM
authors.lastname: Stringer
authors.forename: Dorothy M
authors.initials: DM
authors.lastname: Keefe
mesh_terms: D048948:14-3-3 Proteins / Q000235:genetics / Q000378:metabolism; D000199:Actins / Q000235:genetics / Q000378:metabolism; D000818:Animals; D002166:Camptothecin / Q000031:analogs & derivatives / Q000633:toxicity; D003106:Colon / Q000378:metabolism; D004195:Disease Models, Animal; D005786:Gene Expression Regulation / Q000187:drug effects; D005987:Glyceraldehyde-3-Phosphate Dehydrogenases / Q000235:genetics / Q000378:metabolism; D000077146:Irinotecan; D007583:Jejunum / Q000378:metabolism; D008297:Male; D020778:Matrix Metalloproteinase 2 / Q000235:genetics / Q000378:metabolism; D018832:Molecular Chaperones / Q000235:genetics / Q000378:metabolism; D052016:Mucositis / Q000139:chemically induced / Q000235:genetics* / Q000378:metabolism; D051381:Rats; D013385:Succinate Dehydrogenase / Q000235:genetics / Q000378:metabolism; D025822:Ubiquitin C / Q000235:genetics / Q000378:metabolism; D015854:Up-Regulation
chemical_list: D048948:14-3-3 Proteins; D000199:Actins; D018832:Molecular Chaperones; D025822:Ubiquitin C; C490391:Ywhaz protein, rat; D000077146:Irinotecan; D005987:Glyceraldehyde-3-Phosphate Dehydrogenases; D013385:Succinate Dehydrogenase; D020778:Matrix Metalloproteinase 2; D002166:Camptothecin