mRNA expression analysis of human kallikrein 11 (KLK11) may be useful in the discrimination of benign prostatic hyperplasia from prostate cancer after needle prostate biopsy.

Kallikrein 11 (KLK11, TLSP, hippostatin) is a member of the human kallikrein gene family, which includes PSA, KLK2 and 12 other members, all localized on chromosome 19q13.4. The aim of this study was to investigate whether KLK11 expression could be used to discriminate prostate cancer (CaP) from benign prostatic hyperplasia (BPH) in needle prostate biopsies. We analyzed the expression of the prostate-type variant of the KLK11 gene in 64 CaP and BPH tissues obtained by transrectal ultrasound-guided needle biopsy. Reverse transcription (RT), PCR and image analysis methodologies were developed and used. Of the 42 BPH tissues examined, only 10 (23.8%) were positive for prostate-type KLK11 expression, while of the 22 CaP patients, 12 (54.5%) were KLK11-positive (p=0.025). Logistic regression and receiver operating characteristic curve analyses demonstrated that KLK11 expression has a significant discriminatory value (crude odds ratio=3.84, p=0.016; area under the curve, 0.65, 95% CI 0.51-0.80) between CaP and BPH in needle prostate biopsies.