The glandular epithelium is influenced by sex hormones, such as testosterone and adrenal androgens. These hormones enter the secretory cells of glandular epithelium and are converted to dihydrotestosterone (DHT) by the  enzyme 5-reductase. DHT is approximately 30 times more potent than testosterone. The binding of DHT to the androgen receptor (AR) results in a conformational change of the receptor and its relocation from the cytosol to the cell nucleus. Here the phosphorylated dimers of AR complex bind to a specific sequence of DNA known as a hormone-response element residing in the promoter  regions of target genes. The primary function for AR is direct upor down-regulation of specific gene transcription. DHT stimulates growth of normal prostatic epithelium and proliferation and growth of BPH and androgen-dependent prostate cancer.
The prostate gland secretes prostatic acid phosphatase (PAP), fibrinolysin, citric acid, and prostate-specific antigen (PSA).
The epithelial cells in prostate gland produce several enzymes, particularly prostate-specific antigen (PSA), pro-static acid phosphatase (PAP), fibrinolysin, and citric acid.
 Prostate-specifc antigen (PSA), a 33-kilodalton serine protease, is one of the most clinically important tumor markers. In normal conditions, PSA is secreted into prostatic gland alveoli and ultimately incorporated into seminal fluid. The alveolar secretion from the prostate gland is pumped into the prostatic urethra during ejaculation by contraction of the fibromuscular tissue of the prostate. Because PSA is predominately released into prostatic secretion, only a very small amount of PSA (usually below 4 ng/mL) is circulating in the blood of a healthy individual. However, in prostate cancer, serum concentration of PSA increases; large amounts of PSA are produced and misdirected into the circulation by the transformed  prostatic epithelium. Therefore, the elevated levels of PSA are directly related to increased activity of the prostatic cancer cells. A PSA level between 4 and 10 ng/mL suggests about 25% percent cancer risk; levels above 10 ng/mL suggest a risk greater than 67%. An increased PSA serum level is used as marker for the presence and progression of the disease. Recently, it has become widely accepted that small amounts of PSA are also present in many nonprostatic tissues, including breast, ovary, salivary gland, and liver tissue, and in various tumors. It is also important to mention that high circulating levels of PSA can be associated with benign (noncancerous) conditions such as prostatitis (infection of the prostate gland), interrupted blood fow to the prostate, or BPH.
 The prostatic acid phosphatase (PAP) (100-kilodalton) enzyme regulates cell growth and metabolism of prostate glandular epithelium. Because elevated serum levels of PAP are found in patients with metastatic prostate cancer, this enzyme is routinely used as an alternate marker to PSA for prostatic tumors. Measurements of PAP and PSA are useful in assessing the prognosis of prostate cancer.
 Fibrinolysin, secreted from the prostate gland, liquefies semen.
The bulbourethral glands secrete preseminal fluid.
The paired bulbourethral glands (Cowper’s glands) are pea-sized structures located in the urogenital diaphragm (see Fig. 22.1). The duct of each gland passes through the inferior fascia of the urogenital diaphragm and joins the initial portion of the penile urethra. The glands are compound tubuloalveolar glands that structurally resemble mucus secretory glands (Fig. 22.29). The simple columnar epithelium, which varies considerably in height depending