Prostate-specific antigen

Prostate-specific antigen (PSA) is a protein present in humans. It is encoded by the gene KLK3, which is regulated by androgen receptors. It is present in high concentrations in both male and female ejaculate as well as in blood in much lower concentrations.

Bicalutamide
Bicalutamide inhibits PSA levels via androgen receptor antagonism (specifically, by preventing AR from activating KLK3).

The following table shows the response of PSA levels to varying doses of bicalutamide in prostate cancer patients. Note that prostate cancer can significantly increase PSA production, as PSA is primarily produced in the prostate. As a result, the response curve given in this table may not readily generalize to people without prostate cancer.

5α-Reductase inhibitors
5α-Reductase inhibitors (e.g. finasteride, dutasteride) inhibit PSA levels by about 50% by decreasing DHT concentration.

Cyproterone acetate (with and without estrogens)
Trans women aged 18-50 years (median 30 years) treated with 100 mg/day cyproterone acetate had the following PSA response:

a Only 17 of the original 31 subjects were analyzed at the 12 month mark.

Reference ranges
The following reference ranges are for serum concentrations. Serum PSA levels may be increased by prostatitis, benign prostatic hyperplasia (BPH), and recent ejaculation.