title: Expression of alpha-fetoprotein and prostate-specific antigen genes in several tissues and detection of mRNAs in normal circulating blood by reverse transcriptase-polymerase chain reaction.
abstract: BACKGROUND
  alpha-Fetoprotein (AFP) and prostate-specific antigen (PSA) in serum are widely used as tumor markers in the evaluation of prognosis and management of patients with hepatocellular carcinoma and prostate cancer, respectively. To establish the molecular diagnosis of cancer, reverse transcriptase polymerase chain reaction (RT-PCR) for AFP and PSA was used to identify circulating cancer cells in the blood of cancer patients. Here, we examined the tissue-specificity of AFP and PSA and tested whether AFP and PSA are suitable targets in the detection of certain cancer cells by RT-PCR using peripheral blood samples.
  
  
  METHODS
  Tissue specificity of AFP and PSA was analyzed by Northern blotting and RT-PCR. Probes for AFP and PSA were hybridized with poly A+ RNAs from 50 human tissues. RT-PCR for AFP and PSA mRNA was performed using several cancerous tissues and normal tissues and peripheral blood cells from seven healthy volunteers.
  
  
  RESULTS
  Broad expression of AFP was observed in several tissues and a large amount of AFP mRNA was found in fetal liver. PSA was expressed in prostate, salivary gland, pancreas and uterus. By RT-PCR, AFP and PSA mRNA were detected in several tumors, including salivary pleomorphic adenoma, hilar bile duct carcinoma, pancreatic carcinoma, transitional cell carcinoma of urinary bladder and thyroid papillary carcinoma. Furthermore, AFP and PSA mRNAs were frequently detected by RT-PCR, even in peripheral blood cells from healthy volunteers.
  
  
  CONCLUSIONS
  Neither AFP nor PSA showed tissue-specific expression. AFP and PSA mRNA were detected in several diseased and non-diseased tissues and normal circulating blood by RT-PCR.
authors.affiliation: Department of Biochemistry and Molecular Oncology, Institute of Basic Medical Sciences and Center for Tsukuba Advanced Research Alliance, Ibaraki, Japan.
authors.forename: T
authors.initials: T
authors.lastname: Ishikawa
authors.forename: H
authors.initials: H
authors.lastname: Kashiwagi
authors.forename: Y
authors.initials: Y
authors.lastname: Iwakami
authors.forename: M
authors.initials: M
authors.lastname: Hirai
authors.forename: T
authors.initials: T
authors.lastname: Kawamura
authors.forename: Y
authors.initials: Y
authors.lastname: Aiyoshi
authors.forename: T
authors.initials: T
authors.lastname: Yashiro
authors.forename: Y
authors.initials: Y
authors.lastname: Ami
authors.forename: K
authors.initials: K
authors.lastname: Uchida
authors.forename: M
authors.initials: M
authors.lastname: Miwa
mesh_terms: D008949:Adenoma, Pleomorphic / Q000175:diagnosis; D000328:Adult; D001650:Bile Duct Neoplasms / Q000175:diagnosis; D014408:Biomarkers, Tumor / Q000097:blood*; D006528:Carcinoma, Hepatocellular / Q000175:diagnosis; D002295:Carcinoma, Transitional Cell / Q000175:diagnosis; D005333:Fetus / Q000737:chemistry; D006801:Humans; D008113:Liver Neoplasms / Q000175:diagnosis; D008297:Male; D010190:Pancreatic Neoplasms / Q000175:diagnosis; D017430:Prostate-Specific Antigen / Q000097:blood / Q000235:genetics*; D011471:Prostatic Neoplasms / Q000175:diagnosis; D012333:RNA, Messenger / Q000097:blood; D020133:Reverse Transcriptase Polymerase Chain Reaction; D012468:Salivary Gland Neoplasms / Q000175:diagnosis; D001749:Urinary Bladder Neoplasms / Q000175:diagnosis; D000509:alpha-Fetoproteins / Q000235:genetics / Q000378:metabolism*
chemical_list: D014408:Biomarkers, Tumor; D012333:RNA, Messenger; D000509:alpha-Fetoproteins; D017430:Prostate-Specific Antigen