title: Improved real-time rt-PCR assays of two colorectal cancer peripheral blood mRNA biomarkers: a pilot study.
abstract: Efficient screening for detection of colorectal cancer (CRC) at earlier stages reduces its mortality. The purpose of this study was to investigate expression of carcinoembryonic antigen (CEA) and human telomerase reverse transcriptase (hTERT) mRNA in peripheral blood of CRC patients and to present strategies for early detection screen test.
  
  
  
  Twenty seven patients in non-metastatic stage and 27 healthy individuals were studied. Expression of CEA, hTERT mRNA and 18srRNA (18s subunit of ribosomal RNA, as reference gene) were determined based on real-time RT-PCR on 3 µg of total RNA from blood in 3 separate vials (1 µg per vial).
  
  
  
  Positive expression rate of CEA mRNA (78%) and hTERT mRNA (81%) were higher in patient group (P<0.001). These rates were meaningfully higher than the results of individual vials containing only 1 µg of total RNA. Difference between Ct values of markers with 18srRNA ΔCt) was higher in healthy group than patient one. Therefore, a ΔCt cut-off value was determined for distinguishing between true- and false-positive results. Concurrent expression of both markers was found in 67% of the patients, which was higher than healthy cases (11%). Combination of concurrent marker expression with cut-off point strategy increased specificity to 100%.
  
  
  
  These results showed that concurrent evaluation of marker expression and performing the test on 3 µg of samples in 3 separate vials may increase specificity and sensitivity of real-time RT-PCR for early detection of non-metastatic CRC. However, more investigations with larger numbers of samples are needed to verify these results.
authors.affiliation: Research Center for Molecular Medicine, Hamadan University of Medical Sciences, Hamadan, Iran.|Dept. of Genetics and Molecular Medicine, Hamadan University of Medical Sciences, Hamadan, Iran.
authors.forename: Reza
authors.initials: R
authors.lastname: Yadegarazari
authors.affiliation: Research Center for Molecular Medicine, Hamadan University of Medical Sciences, Hamadan, Iran.
authors.forename: Taghi
authors.initials: T
authors.lastname: Hassanzadeh
authors.affiliation: Dept. of Gastrointestinal Disease, Beheshti Hospital of Hamadan University of Medical Sciences, Hamadan, Iran.
authors.forename: Amir
authors.initials: A
authors.lastname: Majlesi
authors.affiliation: Dept. of General Surgery, Imam Khomeini Hospital of Tehran University of Medical Sciences, Tehran, Iran.
authors.forename: Amir
authors.initials: A
authors.lastname: Keshvari
authors.affiliation: Dept. of Pathology, Hamadan University of Medical Sciences, Hamadan, Iran.
authors.forename: Alireza
authors.initials: A
authors.lastname: Monsef Esfahani
authors.affiliation: Research Center for Molecular Medicine, Hamadan University of Medical Sciences, Hamadan, Iran.
authors.forename: Amirsasan
authors.initials: A
authors.lastname: Tootoonchi
authors.affiliation: Research Center for Molecular Medicine, Hamadan University of Medical Sciences, Hamadan, Iran.|Dept. of Genetics and Molecular Medicine, Hamadan University of Medical Sciences, Hamadan, Iran.
authors.forename: Nooshin
authors.initials: N
authors.lastname: Shabab
authors.affiliation: Research Center for Molecular Medicine, Hamadan University of Medical Sciences, Hamadan, Iran.|Dept. of Genetics and Molecular Medicine, Hamadan University of Medical Sciences, Hamadan, Iran.
authors.forename: Massoud
authors.initials: M
authors.lastname: Saidijam
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D014408:Biomarkers, Tumor / Q000097:blood; D002272:Carcinoembryonic Antigen / Q000097:blood* / Q000235:genetics; D015179:Colorectal Neoplasms / Q000097:blood / Q000175:diagnosis* / Q000235:genetics; D055088:Early Detection of Cancer; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D010865:Pilot Projects; D012333:RNA, Messenger / Q000097:blood*; D012337:RNA, Ribosomal, 18S / Q000097:blood*; D020133:Reverse Transcriptase Polymerase Chain Reaction; D019098:Telomerase / Q000097:blood* / Q000235:genetics
chemical_list: D014408:Biomarkers, Tumor; D002272:Carcinoembryonic Antigen; D012333:RNA, Messenger; D012337:RNA, Ribosomal, 18S; C509186:TERT protein, human; D019098:Telomerase
keywords: Carcinoembryonic antigen; Biomarker; Colorectal cancer