Quantitative analysis of hippostasin/KLK11 gene expression in cancerous and noncancerous prostatic tissues.

OBJECTIVES

Hippostasin/kallikrein 11 (KLK11) is a member of the human kallikrein gene family, which includes prostate-specific antigen (PSA), human kallikrein 2 (hK2), and another 12 members, all localized on chromosome 19q13.4. Hippostasin has two alternative splicing isoforms, known as the brain type and prostate type. We have previously reported that the prostate-type isoform is not expressed in human prostate cancer cell lines.

METHODS

We compared the expression of hippostasin/KLK11 isoforms in 76 matched pairs of human normal and prostate cancer tissues by quantitative reverse transcriptase-polymerase chain reaction.

RESULTS

The expression of both isoforms of KLK11 was 25% to 45% higher in cancer tissues compared with their normal counterparts. Regarding prostate-type KLK11, we identified a significant association between lower expression and higher tumor stage, Gleason score, and tumor grade. No such association was seen with the brain-type isoform.

CONCLUSIONS

: The expression of the prostate-type isoform of KLK11 is increased in prostate cancer. This parameter should be examined further as a new prognostic indicator of prostate cancer.