Prostatic acid phosphatase

Acid phosphatase, prostate
250px PDB rendering based on 1cvi.
Available structures PDB Ortholog search: PDBe, RCSB List of PDB id codes 1CVI, 1ND5, 1ND6, 2HPA, 2L3H, 2L77, 2L79, 2MG0, 3PPD
Identifiers
Symbols	ACPP ; 5'-NT; ACP-3; ACP3
External IDs	OMIM: 171790 MGI: 1928480 HomoloGene: 55552 ChEMBL: 2633 GeneCards: ACPP Gene
EC number	3.1.3.2, 3.1.3.5
Gene ontology Molecular function • acid phosphatase activity • 5'-nucleotidase activity • phosphatase activity • thiamine phosphate phosphatase activity • identical protein binding • lysophosphatidic acid phosphatase activity Cellular component • extracellular space • intracellular • nucleus • lysosomal membrane • plasma membrane • vesicle membrane • integral component of membrane • filopodium • extracellular exosome Biological process • purine nucleobase metabolic process • thiamine metabolic process • nucleotide metabolic process • dephosphorylation • adenosine metabolic process • regulation of sensory perception of pain • positive regulation of adenosine receptor signaling pathway Sources: Amigo / QuickGO
RNA expression pattern
File:PBB GE ACPP 204393 s at tn.png
More reference expression data
Orthologs
Species	Human	Mouse
Entrez	55	56318
Ensembl	ENSG00000014257	ENSMUSG00000032561
UniProt	P15309	Q8CE08
RefSeq (mRNA)	NM_001099	NM_019807
RefSeq (protein)	NP_001090	NP_062781
Location (UCSC)	Chr 3: 132.32 – 132.37 Mb	Chr 9: 104.29 – 104.34 Mb
PubMed search	[1]	[2]

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 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 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 before a test may increase the level.

Its physiological function may be associated with the liquefaction process of semen.

Utility in prostatic cancer

Serum marker

PSAP was used to monitor and assess progression of prostate cancer until the introduction of prostate specific antigen (PSA), which has now largely displaced it. Recent work, suggesting it has a role in prognosticating intermediate and high-risk prostate cancer, has led to renewed interest in this marker.

Immunohistochemistry

PSAP immunohistochemical staining is often used with PSA (staining), by pathologists, to help distinguish poorly differentiated carcinomas. For example, poorly differentiated prostate adenocarcinoma (prostate cancer) and urothelial carcinoma (bladder cancer) may appear similar under the microscope, but PSAP and PSA staining can help differentiate them; prostate adenocarcinoma often stains with PSA and/or PSAP, while urothelial carcinoma does not.

Presumptive test for semen

Prostatic acid phosphatase is present in semen and its presence can be used as a presumptive test for semen. Other acid phosphatases are present in other bodily fluids, but the high concentration of PAP in semen gives a strong indication that semen is present.

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 which PAP converts into adenosine, a molecule known to suppress pain.

History

PSAP was the first useful serum tumour marker and emerged in the 1940s and 1950s.

See also

• Adenocarcinoma not otherwise specified

External links

• prostatic acid phosphatase at the US National Library of Medicine Medical Subject Headings (MeSH)