The prostate is both an accessory gland of the male reproductive system and a muscle-driven mechanical switch between urination and ejaculation. It is found in all male mammals. It differs between species anatomically, chemically, and physiologically. Anatomically, the prostate is found below the bladder, with the urethra passing through it. It is described in gross anatomy as consisting of lobes and in microanatomy by zone. It is surrounded by an elastic, fibromuscular capsule and contains glandular tissue, as well as connective tissue.
Benign prostatic hyperplasia (BPH), also called prostate enlargement, is a noncancerous increase in size of the prostate gland. Symptoms may include frequent urination, trouble starting to urinate, weak stream, inability to urinate, or loss of bladder control. Complications can include urinary tract infections, bladder stones, and chronic kidney problems.
Liver tumors are abnormal growth of liver cells on or in the liver. Several distinct types of tumors can develop in the liver because the liver is made up of various cell types. Liver tumors can be classified as benign (non-cancerous) or malignant (cancerous) growths. They may be discovered on medical imaging, and the diagnosis is often confirmed with liver biopsy. Signs and symptoms of liver masses vary from being asymptomatic to patients presenting with an abdominal mass, hepatomegaly, abdominal pain, jaundice, or some other liver dysfunction. Treatment varies and is highly specific to the type of liver tumor.
Prostate-specific antigen (PSA), also known as gamma-seminoprotein or kallikrein-3 (KLK3), P-30 antigen, is a glycoprotein enzyme encoded in humans by the KLK3 gene. PSA is a member of the kallikrein-related peptidase family and is secreted by the epithelial cells of the prostate gland in men and the paraurethral glands in women.
Tadalafil, sold under the brand name Cialis among others, is a medication used to treat erectile dysfunction, benign prostatic hyperplasia, and pulmonary arterial hypertension. It is taken by mouth. Onset is typically within half an hour and the duration is up to 36 hours.
Hyperplasia, or hypergenesis, is an enlargement of an organ or tissue caused by an increase in the amount of organic tissue that results from cell proliferation. It may lead to the gross enlargement of an organ, and the term is sometimes confused with benign neoplasia or benign tumor.
Finasteride, sold under the brand names Proscar and Propecia among others, is a medication used to treat pattern hair loss and benign prostatic hyperplasia (BPH) in men. It can also be used to treat excessive hair growth in women. It is usually taken orally but there are topical formulations for patients with hair loss, designed to minimize systemic exposure by acting specifically on hair follicles.
5α-Reductases, also known as 3-oxo-5α-steroid 4-dehydrogenases, are enzymes involved in steroid metabolism. They participate in three metabolic pathways: bile acid biosynthesis, androgen and estrogen metabolism. There are three isozymes of 5α-reductase encoded by the genes SRD5A1, SRD5A2, and SRD5A3.
Cytochrome P450 17A1 is an enzyme of the hydroxylase type that in humans is encoded by the CYP17A1 gene on chromosome 10. It is ubiquitously expressed in many tissues and cell types, including the zona reticularis and zona fasciculata of the adrenal cortex as well as gonadal tissues. It has both 17α-hydroxylase and 17,20-lyase activities, and is a key enzyme in the steroidogenic pathway that produces progestins, mineralocorticoids, glucocorticoids, androgens, and estrogens. More specifically, the enzyme acts upon pregnenolone and progesterone to add a hydroxyl (-OH) group at carbon 17 position (C17) of the steroid D ring, or acts upon 17α-hydroxyprogesterone and 17α-hydroxypregnenolone to split the side-chain off the steroid nucleus.
An adrenocortical adenoma or adrenal adenoma is commonly described as a benign neoplasm emerging from the cells that comprise the adrenal cortex. Like most adenomas, the adrenocortical adenoma is considered a benign tumor since the majority of them are non-functioning and asymptomatic. Adrenocortical adenomas are classified as ACTH-independent disorders, and are commonly associated with conditions linked to hyperadrenalism such as Cushing's syndrome (hypercortisolism) or Conn's syndrome (hyperaldosteronism), which is also known as primary aldosteronism. In addition, recent case reports further support the affiliation of adrenocortical adenomas with hyperandrogenism or florid hyperandrogenism which can cause hyperandrogenic hirsutism in females. "Cushing's syndrome" differs from the "Cushing's disease" even though both conditions are induced by hypercortisolism. The term "Cushing's disease" refers specifically to "secondary hypercortisolism" classified as "ACTH-dependent Cushing's syndrome" caused by pituitary adenomas. In contrast, "Cushing's syndrome" refers specifically to "primary hypercortisolism" classified as "ACTH-independent Cushing's syndrome" caused by adrenocortical adenomas.
Kimura's disease is a benign rare chronic inflammatory disorder. Its primary symptoms are subdermal lesions in the head or neck or painless unilateral inflammation of cervical lymph nodes.
Epristeride, sold under the brand names Aipuliete and Chuanliu, is a medication which is used in the treatment of enlarged prostate in China. It is taken by mouth.
Oxendolone, sold under the brand names Prostetin and Roxenone, is an antiandrogen and progestin medication which is used in Japan in the treatment of enlarged prostate. However, this use is controversial due to concerns about its clinical efficacy. Oxendolone is not effective by mouth and must be given by injection into muscle.
BOMT, also known by its developmental code name Ro 7-2340 and as 6α-bromo-4-oxa-17α-methyl-5α-dihydrotestosterone, is a synthetic steroidal antiandrogen which was first produced in 1970 and was never marketed for medical use. It is the 6α-brominated, 4-oxygenated, and 17α-methylated derivative of the androgen dihydrotestosterone (DHT). Along with benorterone, cyproterone, and flutamide, BOMT was among the earliest antiandrogens to be developed and extensively studied, although it is less well-documented in comparison to the others. BOMT has been investigated clinically in the treatment of benign prostatic hyperplasia, though development for this use did not continue. There was also interest in BOMT for the potential applications of acne, pattern hair loss, and possibly prostate cancer, but it was not developed for these indications either.
This article is about the discovery and development of 5α-reductase inhibitors (5-ARIs), also known as dihydrotestosterone (DHT) blockers.
Helen Nicholson is a New Zealand medical academic specialising in male reproductive health. She is a full professor and served as Acting Vice-Chancellor of the University of Otago between March 2023 and June 2024.
The androgen backdoor pathway is responsible for the synthesis of physiologically relevant androgens. This process starts with 21-carbon steroids, also known as pregnanes, and involves a step called "5α-reduction". Notably, this pathway does not require the intermediate formation of testosterone, hence the term "bypassing testosterone" is sometimes used in medical literature as the hallmark feature of this way of androgen biosynthesis. This feature is a key distinction from the conventional, canonical androgenic pathway, which necessitates the involvement of testosterone as an intermediate in the synthesis of androgens.
Jacqueline Dianne Kidd (Ngāpuhi) is a Māori academic, and is a full professor at the Auckland University of Technology, specialising in Māori health and anti-racism in health practices and processes.
Philippa Seaton is a New Zealand academic, and is a full professor at the University of Otago, specialising in nursing education.
Elizabeth Mary Ditzel is a New Zealand nursing academic, and is a full professor at the Otago Polytechnic, specialising in nursing education, curriculum development, and the use of new technology within the nursing curriculum.
