title: Independent patterns of cytochrome P450 gene expression in liver and blood in patients with suspected liver disease.
abstract: OBJECTIVE
  Assessment of liver metabolism using blood samples was tested by comparison of cytochrome P450 (CYP) gene expression in paired liver and blood samples from 13 individuals.
  
  
  METHODS
  Total RNA was isolated from percutaneous needle biopsies and blood collected simultaneously. Gene expression for CYP1A2, CYP1B1, CYP2E1 and CYP3A4 was studied using a real-time reverse-transcription polymerase chain reaction (RT-PCR) method.
  
  
  RESULTS
  All CYP mRNA species were expressed in all liver biopsies but at varying levels. The highest and lowest levels of expression were observed for CYP2E1 and CYP1B1, respectively. The expression patterns differed between blood and liver. CYP1B1 was expressed in all blood samples at a 20% higher level than in the liver. CYP1A2, CYP2E1 and CYP3A4 were expressed in blood at 35- to 5,000-fold lower levels than in liver. None of the transcripts in blood showed any correlation with the expression in liver.
  
  
  CONCLUSIONS
  We conclude that blood cannot serve as a surrogate organ for assessment of the expression of the studied CYP genes in liver.
authors.affiliation: Department of Medical Laboratory Sciences and Technology, Karolinska Institute, Huddinge University Hospital, Stockholm, Sweden. Niklas.Finnstrom@labtek.ki.se
authors.forename: N
authors.initials: N
authors.lastname: Finnström
authors.forename: M
authors.initials: M
authors.lastname: Thörn
authors.forename: L
authors.initials: L
authors.lastname: Lööf
authors.forename: A
authors.initials: A
authors.lastname: Rane
mesh_terms: D000328:Adult; D000368:Aged; D001707:Biopsy, Needle; D003577:Cytochrome P-450 Enzyme System / Q000097:blood* / Q000235:genetics / Q000378:metabolism*; D005260:Female; D015971:Gene Expression Regulation, Enzymologic; D006801:Humans; D007527:Isoenzymes / Q000097:blood / Q000235:genetics / Q000378:metabolism; D008099:Liver / Q000201:enzymology; D008107:Liver Diseases / Q000097:blood / Q000201:enzymology* / Q000473:pathology; D008297:Male; D008875:Middle Aged; D012333:RNA, Messenger / Q000032:analysis; D012015:Reference Standards; D020133:Reverse Transcriptase Polymerase Chain Reaction; D014158:Transcription, Genetic
chemical_list: D007527:Isoenzymes; D012333:RNA, Messenger; D003577:Cytochrome P-450 Enzyme System