KLK9 explained

Kallikrein-related peptidase 9 also known as KLK9 is an enzyme which in humans is encoded by the KLK9 gene.^[1]

Function

KLK9 belongs to the kallikrein subgroup of serine proteases, which have diverse physiologic functions in many tissues.^{[2] [3] [4]} KLK9 is primarily expressed in thymus, testis, spinal cord, cerebellum, trachea, mammary gland, prostate, brain, salivary gland, ovary, and skin.^[1]

Clinical significance

KLK9 is under steroid hormone regulation in ovarian and breast cancer cell lines and is a potential prognostic marker for early-stage ovarian^[5] and breast cancer patients.^[6]

Further reading

• Yousef GM, Kyriakopoulou LG, Scorilas A, Fracchioli S, Ghiringhello B, Zarghooni M, Chang A, Diamandis M, Giardina G, Hartwick WJ, Richiardi G, Massobrio M, Diamandis EP, Katsaros D . Quantitative expression of the human kallikrein gene 9 (KLK9) in ovarian cancer: a new independent and favorable prognostic marker . Cancer Research . 61 . 21 . 7811–8 . November 2001 . 11691797 .
• Yousef GM, Luo LY, Diamandis EP . Identification of novel human kallikrein-like genes on chromosome 19q13.3-q13.4 . Anticancer Research . 19 . 4B . 2843–52 . 1999 . 10652563 .
• Gan L, Lee I, Smith R, Argonza-Barrett R, Lei H, McCuaig J, Moss P, Paeper B, Wang K . Sequencing and expression analysis of the serine protease gene cluster located in chromosome 19q13 region . Gene . 257 . 1 . 119–30 . October 2000 . 11054574 . 10.1016/S0378-1119(00)00382-6 .

External links

• The MEROPS online database for peptidases and their inhibitors: S01.307

Notes and References

1. Yousef GM, Diamandis EP . The expanded human kallikrein gene family: locus characterization and molecular cloning of a new member, KLK-L3 (KLK9) . Genomics . 65 . 2 . 184–94 . April 2000 . 10783266 . 10.1006/geno.2000.6159 . 10.1.1.326.8491 .
2. Web site: Entrez Gene: KLK9 .
3. Lundwall A, Band V, Blaber M, Clements JA, Courty Y, Diamandis EP, Fritz H, Lilja H, Malm J, Maltais LJ, Olsson AY, Petraki C, Scorilas A, Sotiropoulou G, Stenman UH, Stephan C, Talieri M, Yousef GM . A comprehensive nomenclature for serine proteases with homology to tissue kallikreins . Biological Chemistry . 387 . 6 . 637–41 . June 2006 . 16800724 . 10.1515/BC.2006.082 . 436200 .
4. Diamandis . Eleftherios P. . Deperthes . David . Lundwall . Åke . vanc . Proceedings of the 1st International Symposium on Kallikreins, Lausanne, Switzerland, September 1-3, 2005 . Biological Chemistry . 387 . 6 . 635–824 . June 2006 . 16800723 . 10.1515/BC.2006.081 . 83910246 .
5. Yousef GM, Kyriakopoulou LG, Scorilas A, Fracchioli S, Ghiringhello B, Zarghooni M, Chang A, Diamandis M, Giardina G, Hartwick WJ, Richiardi G, Massobrio M, Diamandis EP, Katsaros D . Quantitative expression of the human kallikrein gene 9 (KLK9) in ovarian cancer: a new independent and favorable prognostic marker . Cancer Research . 61 . 21 . 7811–8 . November 2001 . 11691797 .
6. Yousef GM, Scorilas A, Nakamura T, Ellatif MA, Ponzone R, Biglia N, Maggiorotto F, Roagna R, Sismondi P, Diamandis EP . The prognostic value of the human kallikrein gene 9 (KLK9) in breast cancer . Breast Cancer Research and Treatment . 78 . 2 . 149–58 . March 2003 . 12725415 . 10.1023/A:1022931403825 . 6515644 .