Prostatic acid phosphatase (PAP), also prostatic specific acid phosphatase (PSAP), is an enzyme produced by the prostate. It may be found in increased amounts in men who have

prostate cancer Prostate cancer is cancer of the prostate. Prostate cancer is the second most common cancerous tumor worldwide and is the fifth leading cause of cancer-related mortality among men. The prostate is a gland in the male reproductive system that sur ...

or other diseases. The highest levels of acid phosphatase are found in metastasized prostate cancer. Diseases of the bone, such as Paget's disease or hyperparathyroidism, diseases of blood cells, such as sickle-cell disease or

multiple myeloma Multiple myeloma (MM), also known as plasma cell myeloma and simply myeloma, is a cancer of plasma cells, a type of white blood cell that normally produces antibodies. Often, no symptoms are noticed initially. As it progresses, bone pain, an ...

or lysosomal storage diseases, such as Gaucher's disease, will show moderately increased levels. Certain medications can cause temporary increases or decreases in acid phosphatase levels. Manipulation of the prostate gland through massage, biopsy or

rectal exam Digital rectal examination (DRE; la, palpatio per anum, PPA) is an internal examination of the rectum, performed by a healthcare provider. Prior to a 2018 report from the U.S. Preventive Services Task Force, the DRE was a common and "dreaded" co ...

before a test may increase the level. Its physiological function may be associated with the liquefaction process of semen.Page 1135-1136 in:

Use in prostatic cancer prognosis

Serum marker

PSAP was used to monitor and assess progression of

until the introduction of prostate specific antigen (PSA), which has now largely displaced it. Subsequent work, suggested that it has a role in prognosticating intermediate and high-risk prostate cancer, and led to renewed interest in it as a biomarker.

Immunohistochemistry

PSAP immunohistochemical staining is often used with PSA (staining), by pathologists, to help distinguish poorly differentiated

carcinoma Carcinoma is a malignancy that develops from epithelial cells. Specifically, a carcinoma is a cancer that begins in a tissue that lines the inner or outer surfaces of the body, and that arises from cells originating in the endodermal, mesodermal ...

s. For example, poorly differentiated prostate adenocarcinoma (

) and urothelial carcinoma ( bladder cancer) may appear similar under the microscope, but PSAP and

PSA PSA, PsA, Psa, or psa may refer to: Biology and medicine * Posterior spinal artery * Primary systemic amyloidosis, a disease caused by the accumulation of abnormal proteins * Prostate-specific antigen, an enzyme used as a blood tracer for pros ...

staining can help differentiate them; prostate adenocarcinoma often stains with PSA and/or PSAP, while urothelial carcinoma does not.

HIV

PAP may play an important role in the transmission of HIV. Researchers at the University of Ulm in Germany found that PAP forms fibers made of amyloid. They called the fibers Semen-derived Enhancer of Virus Infection (SEVI) and showed that they capture HIV virions promoting their attachment to target cells. The association of PAP with HIV may increase the ability of the virus to infect human cells "by several orders of magnitude." PAP may be a future target of efforts to combat the spread of HIV infection.

Pain suppression

A study at the University of North Carolina and University of Helsinki suggested that PAP could have potent antinociceptive, antihyperalgesic, and antiallodynic effects that last longer than morphine. One dose of PAP lasted for up to three days, much longer than the five hours gained with a single dose of morphine. When in distress, nerve cells release a chemical known as adenosine triphosphate (ATP) which in turn invokes a painful sensation. ATP is broken down into AMP ( adenosine monophosphate), which PAP converts into

adenosine Adenosine ( symbol A) is an organic compound that occurs widely in nature in the form of diverse derivatives. The molecule consists of an adenine attached to a ribose via a β-N9-glycosidic bond. Adenosine is one of the four nucleoside building ...

, a molecule known to suppress pain.

History

PSAP was the first useful

serum Serum may refer to: *Serum (blood), plasma from which the clotting proteins have been removed **Antiserum, blood serum with specific antibodies for passive immunity * Serous fluid, any clear bodily fluid * Truth serum, a drug that is likely to mak ...

tumour marker A tumor marker is a biomarker found in blood, urine, or body tissues that can be elevated by the presence of one or more types of cancer. There are many different tumor markers, each indicative of a particular disease process, and they are used in ...

and emerged in the 1940s and 1950s.

References

External links

* {{Tumor markers HIV/AIDS Tumor markers Prostate Prostate cancer