Expression profile of human tissue kallikrein 15 provides preliminary insights into its roles in the prostate and testis

Clin Biochem. 2018 Sep:59:78-85. doi: 10.1016/j.clinbiochem.2018.06.017. Epub 2018 Jun 26.

Abstract

Background: Human tissue kallikrein 15 (KLK15) is the latest member of the kallikrein-related peptidase family. Little is known about the pathophysiological roles of KLK15. Previous studies implied a role of KLK15 in prostate cancer.

Methods: In the present study, we examined KLK15 protein expression using a new immunoassay (ELISA) and immunohistochemistry (IHC).

Results: Highest KLK15 levels were detected in the testis and seminal fluid, whereas lower levels were observed in prostate and other tissues. Immunohistochemical analysis of testis suggests that KLK15 is strongly expressed in mature spermatids, but not in immature germ cells. KLK15 displayed predominantly nuclear localization in the basal cell layer of the prostatic epithelium. We also measured KLK15 in supernatants of various cell lines. Highest KLK15 levels were primarily detected in prostate cancer cell lines and KLK15 expression was hormone-independent, in contrast to KLK3.

Conclusions: Collectively, our data provide insights into the localization and possible role of KLK15 in human physiology.

Keywords: Cancer cell lines; Immunoassays; Immunohistochemistry; KLK15; Kallikreins; Prostate cancer.

MeSH terms

  • Adult
  • Cell Line, Tumor
  • Enzyme-Linked Immunosorbent Assay
  • Humans
  • Immunohistochemistry
  • Jurkat Cells
  • Kallikreins / biosynthesis*
  • Kallikreins / genetics*
  • Kallikreins / metabolism
  • Male
  • Prostate / enzymology*
  • Prostatic Neoplasms / enzymology
  • RNA, Messenger / genetics
  • RNA, Messenger / metabolism
  • Semen / enzymology
  • Testis / enzymology*
  • Transcriptome

Substances

  • RNA, Messenger
  • KLK15 protein, human
  • Kallikreins