title: Expression of A1 and A3 adenosine receptors in human breast tumors.
abstract: BACKGROUND
  Adenosine receptors (A1, A2A, A2B, A3) play an important role in the regulation of growth, proliferation and death of cancer and normal cells. We recently showed the expression profile of A2A and A2B receptors in normal and tumor breast tissues. In the present study, we used semiquantitative RT-PCR to measure the A1 and A3 gene expression levels in normal and tumor breast tissues.
  
  
  METHODS
  Breast tumors (n = 18) and non-neoplastic mammary tissues (n = 10) were collected and histologically confirmed to be neoplastic or non-neoplastic, respectively. Total RNA was extracted and reverse transcribed into cDNA, and PCR was performed under optimized condition for each receptor subtype. Amplification of beta-actin mRNA served as control for RT-PCR. The PCR products were separated on 1.7% agarose gels. The intensity of the bands was quantitated with ImageJ software after normalization against beta-actin expression.
  
  
  RESULTS
  All breast tumor and normal tissue specimens expressed A1 and A3 adenosine receptor transcripts. However, we observed that the expression level of the A3 receptor in tumor tissues was 1.27-fold that of normal tissues, whereas there was no significant difference between the expression levels of A1 in normal and tumor tissues.
  
  
  CONCLUSIONS
  Interestingly, the results of the present study indicate that breast tumors exhibit a higher level of A3 transcripts (than normal tissues) and support the possible key role of A3 adenosine receptor in tumor development. However, further studies based on real-time quantitative RT-PCR are needed to identify the exact gene expression levels.
authors.affiliation: Department of Biochemistry, School of Pharmacy and Pharmaceutical Sciences, Isfahan University of Medical Sciences, Isfahan, Iran. panjehpour@pharm.mui.ac.ir
authors.forename: Mojtaba
authors.initials: M
authors.lastname: Panjehpour
authors.forename: Simin
authors.initials: S
authors.lastname: Hemati
authors.forename: Mohammad Ali
authors.initials: MA
authors.lastname: Forghani
mesh_terms: D000328:Adult; D000368:Aged; D001940:Breast / Q000737:chemistry; D001943:Breast Neoplasms / Q000737:chemistry*; D018076:DNA, Complementary / Q000032:analysis; D004587:Electrophoresis, Agar Gel; D005260:Female; D015972:Gene Expression Regulation, Neoplastic; D006801:Humans; D008875:Middle Aged; D012333:RNA, Messenger / Q000032:analysis; D043682:Receptor, Adenosine A1 / Q000032:analysis* / Q000235:genetics; D043684:Receptor, Adenosine A3 / Q000032:analysis* / Q000235:genetics; D020133:Reverse Transcriptase Polymerase Chain Reaction
chemical_list: D018076:DNA, Complementary; D012333:RNA, Messenger; D043682:Receptor, Adenosine A1; D043684:Receptor, Adenosine A3