Optimization of the reverse transcriptase polymerase chain reaction for the detection of circulating prostate cells.
The reverse transcriptase polymerase chain reaction (RT-PCR) is a sensitive technique that can detect prostate-specific messenger RNA in circulating blood. Many authors have studied the potential of RT-PCR as a staging technique in prostate cancer (PC). Clinical sensitivity and in some cases specificity has been disappointing. Few authors have been able to correlate RT-PCR result with patient stage. We have compared the results of using two different RT-PCR protocols with different sensitivities on blood samples from prostate cancer patients. An 80-amplification-cycle nested primer RT-PCR assay had a detection limit of 10 prostate cells and a 50-cycle RT-PCR could detect 20 cells in 5 ml blood. The 80-cycle assay detected prostate mRNA in four of 10 female samples, whereas the 50-cycle assay detected it in none. There was little difference in the assays' ability to detect prostate mRNA in advanced PC patients. The 50-cycle assay could differentiate between hormone-escaped, stable hormone-treated and untreated localized PC patients, whereas the 80-cycle assay could not. Each blood sample must be assayed several times with RT-PCR to avoid false-negative results and, if this is done, assay specificity can be increased with little effect on clinical sensitivity.
McIntyre
I G
IG
Department of Urology, Withington Hospital, Manchester, M21 1AH, UK.
Spreckley
K
K
Clarke
R B
RB
Anderson
E
E
Clarke
N W
NW
George
N J
NJ
D005188:False Negative Reactions; D005260:Female; D006801:Humans; D008297:Male; D009367:Neoplasm Staging; D016133:Polymerase Chain Reaction / Q000379:methods*; D017430:Prostate-Specific Antigen / Q000097:blood* / Q000235:genetics; D011471:Prostatic Neoplasms / Q000097:blood* / Q000473:pathology*; D012333:RNA, Messenger / Q000097:blood*; D012016:Reference Values; D015203:Reproducibility of Results; D020133:Reverse Transcriptase Polymerase Chain Reaction; D012680:Sensitivity and Specificity
D012333:RNA, Messenger; D017430:Prostate-Specific Antigen