PSA (hK3) is synthesized by the prostate ductal and acinal epitphelium and secteted into the lumen. (Gilgunn et. al. 2013, Nat. Rev. Urology). PSA is initially translated as preproPSA and cotranslationaly clevead to proPSA. Both are inactive forms of the protein. proPSA is then activated by hK2 or hK4. hK2 and hK4 are expressed in by prostate secretory epithelium (Balk et. al. 2003, J. of Clin. Oncology).

Does anyone know whether PSA (hK3), hK2 and hK4 are expressed in the same cells. If so, PSA could already be inactivated in the cells, or not?

Is there only inactive PSA in the cells, ore active forms too?

Are there publications on this subject?

Many thanks for the help.