Relative concentrations of hK2/PSA mRNA in benign and malignant prostatic tissue.
BACKGROUND
Prostate-specific antigen (PSA/KLK3) and human kallikrein 2 (hK2/KLK2) belong to the human kallikrein gene family. These two highly homologous genes are specifically expressed in the prostate under androgen control. Expression of these is regulated by similar mechanisms but changes in their relative expression have been observed in prostate cancer.


METHODS
We determined the relative levels of PSA and hK2 mRNA in benign and malignant prostate tissue using a quantitative reverse transcription-polymerase chain reaction (RT-PCR) method. The mRNA of PSA and hK2 are reverse transcribed and amplified in one reaction with the same primers.


RESULTS
The variation in the ratio of hK2/PSA mRNA was remarkably small, the difference between the highest and lowest values being three-fold. The ratio was significantly higher in WHO grade 2 compared to normal or benign prostatic hyperplasia tissue (P = 0.032 and P = 0.035, respectively) and in grade 3 compared to normal or benign prostatic hyperplasia tissue (P = 0.006 in both).


CONCLUSIONS
The new quantitative RT-PCR technique facilitates very accurate quantitation of the relative mRNA levels of homologous genes. Using this method we have shown that the ratio of hK2/PSA mRNA is higher in cancerous than in benign prostatic tissue.
Lintula
Susanna
S
Department of Clinical Chemistry, Helsinki University Central Hospital, Helsinki, Finland. susanna.lintula@hus.fi
Stenman
Jakob
J
Bjartell
Anders
A
Nordling
Stig
S
Stenman
Ulf-Håkan
UH
D014408:Biomarkers, Tumor / Q000235:genetics; D045744:Cell Line, Tumor; D015972:Gene Expression Regulation, Neoplastic; D006801:Humans; D008297:Male; D017430:Prostate-Specific Antigen / Q000235:genetics*; D011470:Prostatic Hyperplasia / Q000503:physiopathology*; D011471:Prostatic Neoplasms / Q000503:physiopathology*; D012333:RNA, Messenger / Q000032:analysis; D015203:Reproducibility of Results; D020133:Reverse Transcriptase Polymerase Chain Reaction / Q000379:methods / Q000592:standards; D020840:Tissue Kallikreins / Q000235:genetics*
D014408:Biomarkers, Tumor; D012333:RNA, Messenger; D020840:Tissue Kallikreins; D017430:Prostate-Specific Antigen