Expression analysis and prognostic significance of human kallikrein 11 in prostate cancer.
BACKGROUND
Kallikrein 11 (KLK11) is a newly discovered human kallikrein gene that is mainly expressed in the central nervous system and endocrine tissues. KLK11 has two alternative splicing isoforms, known as the brain type and prostate type. Many members of the human kallikrein gene family are differentially expressed in cancer and a few have potential as diagnostic/prognostic markers.


METHODS
In the present study, the expression of prostate type variant of KLK11 gene was analyzed by RT-PCR in 66 prostate cancer tissues. Tumors were pulverized, total RNA was extracted, and cDNA was prepared by reverse transcription. KLK11 was amplified by PCR using gene specific primers and its identity was verified by sequencing. Prostate tissues were then classified as KLK5 positive or negative based on eithidium bromide staining in agarose gels and image analysis.


RESULTS
KLK11 was found to be highly expressed in 43/66 (65%) of prostate cancer samples. We found a significant negative relationship between KLK11 expression and Gleason score (p = 0.004) and disease stage (p = 0.038). Serum total PSA concentration was found to be lower in patients with overexpression of KLK11 (p = 0.044).


CONCLUSIONS
We conclude that down-regulation of the KLK11 gene in advanced and more aggressive tumors may open the possibility of being used as a future biological marker distinguishing the tumor aggressiveness as well as a useful prognostic biomarker for prostate cancer.
Stavropoulou
Panagiota
P
Department of Biochemistry and Molecular Biology, Faculty of Biology, University of Athens, 157 01 Athens, Greece.
Gregorakis
Alkiviades K
AK
Plebani
Mario
M
Scorilas
Andreas
A
D000368:Aged; D020869:Gene Expression Profiling; D015972:Gene Expression Regulation, Neoplastic; D006801:Humans; D007610:Kallikreins / Q000235:genetics / Q000378:metabolism*; D008297:Male; D008875:Middle Aged; D009367:Neoplasm Staging; D011379:Prognosis; D017430:Prostate-Specific Antigen / Q000097:blood; D011471:Prostatic Neoplasms / Q000175:diagnosis* / Q000235:genetics / Q000378:metabolism* / Q000473:pathology
D007610:Kallikreins; D017430:Prostate-Specific Antigen