PTEN

Definition: PTEN is a tumor suppressor gene that is frequently deleted or mutated in prostate, endometrial and breast cancer. This lipid phosphatase regulates cell survival, growth and migration.

PTEN suppresses phosphoinositol-3-kinase (PI3K) signaling, thereby down-regulating downstream mediators, including the oncogenic serine-threonine kinase AKT, which in turn regulates the mTOR (mammalian target of rapamycin) growth pathway.

PTEN activity causes cell-cycle arrest and apoptosis as well as inhibition of cell motility. It has been proposed that PTEN blocks the cell cycle by increasing the transcription of the p27 Cip/Kip cell-cycle inhibitor and stabilizing the protein.

Function

As the primary phosphatase of phosphatidylinositol (3,4,5)-trisphosphate, PTEN has a central role in reigning in the phosphoinositide 3-kinase (PI 3-kinase) network to control cellular homeostasis.

Cells that lack PTEN are unable to regulate the PtdIns 3-kinase programme, which stimulates a variety of cellular phenotypes that favour oncogenesis.

 tumour suppressor
 regulation of basic cellular functions

• cell migration
• cell size
• contractility of cardiac myocytes
• chemotaxis.

Pathology

Phosphatase and tensin homologue, deleted on chromosome 10 (PTEN) gene, mapped on chromosome 10q23, is frequently deleted in many human cancers but at particularly high frequency in endometrial carcinomas and glioblastomas. With loss of PTEN, therefore, cells are released into the cell cycle.

Mutations of the PTEN gene cause a dysregulation of the phosphoinositol-3-kinase/Akt pathway. The tumor suppressor properties of Pten are closely related to its inhibitory effect on the phosphatidyl-inositol-3’-kinase (Pi3k)-dependent activation of protein kinase B (Akt) signalling.

 germline mutations

• Lhermitte-Duclos disease (dysplastic gangliocytoma of the cerebellum)(MIM.158350)
• autosomal recessive VATER association with hydrocephalus (MIM.276950)
• Proteus syndrome (MIM.176920)
• PTEN-associated tumor syndromes
  • Cowden disease (MIM.158350) (80%)
  • Bannayan-Zonana syndrome or Bannayan-Ruvalcaba-Riley syndrome (BRRS) (MIM.153480) (60%)

 somatic mutations in cancer

• endometrial adenocarcinoma
• prostatic adenocarcinoma
• mammary adenocarcinoma
• malignant melanoma
• oligodendroglioma
• glioblastoma (24%)
• epidermoid carcinoma of head and neck

 Wilms tumor

• Loss of PTEN/MMAC1 activity is a rare and late event in the pathogenesis of Wilms tumor (nephroblastoma) (20381115)
• PTEN loss is associated with upgrading of prostate cancer from biopsy to radical prostatectomy. (24993522)

 prostate cancer

• Loss of PTEN expression is associated with increased risk of recurrence after prostatectomy for clinically localized prostate cancer. (22684219)

 gallbladder cancer

• Inactivation of tumor suppressor gene pten in early and advanced gallbladder cancer. (26294099)

Immunochemistry

 Immunohistochemical staining of thyroidectomy specimens for PTEN can aid in the identification of patients with Cowden syndrome. (21921783)

Animal models

 Deletion of Pten in the mouse enteric nervous system induces ganglioneuromatosis and mimics intestinal pseudoobstruction. (19884655)

Links

 PTEN central at Women’s and Perinatal Pathology, Brigham and Women’s Hospital, Boston, MA

See also

 PTEN/Akt pathway

Open references

 Inactivation of tumor suppressor gene pten in early and advanced gallbladder cancer. Roa I, de Toro G, Fernández F, Game A, Muñoz S, de Aretxabala X, Javle M. Diagn Pathol. 2015 Aug 21;10:148. doi : 10.1186/s13000-015-0381-2 PMID: 26294099 (Free)

 PTEN loss is associated with upgrading of prostate cancer from biopsy to radical prostatectomy. Lotan TL, Carvalho FL, Peskoe SB, Hicks JL, Good J, Fedor HL, Humphreys E, Han M, Platz EA, Squire JA, De Marzo AM, Berman DM. Mod Pathol. 2015 Jan;28(1):128-37. doi : 10.1038/modpathol.2014.85 PMID: 24993522 (Free)

 Loss of PTEN expression is associated with increased risk of recurrence after prostatectomy for clinically localized prostate cancer. Chaux A, Peskoe SB, Gonzalez-Roibon N, Schultz L, Albadine R, Hicks J, De Marzo AM, Platz EA, Netto GJ. Mod Pathol. 2012 Jun 8. PMID: 22684219 (Free)

References

 Immunohistochemical staining of thyroidectomy specimens for PTEN can aid in the identification of patients with Cowden syndrome. Barletta JA, Bellizzi AM, Hornick JL. Am J Surg Pathol. 2011 Oct;35(10):1505-11. PMID: 21921783

 Deletion of Pten in the mouse enteric nervous system induces ganglioneuromatosis and mimics intestinal pseudoobstruction. Puig I, Champeval D, De Santa Barbara P, Jaubert F, Lyonnet S, Larue L. J Clin Invest. 2009 Nov 2. PMID: 19884655

Reviews

 Zbuk KM, Eng C. Cancer phenomics: RET and PTEN as illustrative model. Nat Rev Cancer. 2007 Jan;7(1):35-45. PMID: 17167516

 Cheung AM, Mak TW. PTEN in the haematopoietic system and its therapeutic indications. Trends Mol Med. 2006 Sep 21; PMID: 16996801

 Brader S, Eccles SA. Phosphoinositide 3-kinase signalling pathways in tumor progression, invasion and angiogenesis. Tumori. 2004 Jan-Feb;90(1):2-8. PMID: 15143962

 Goberdhan DC, Wilson C. PTEN: tumour suppressor, multifunctional growth regulator and more. Hum Mol Genet. 2003 Oct 15;12 Spec No 2:R239-48. PMID: 12928488

 Eng C. PTEN: one gene, many syndromes. Hum Mutat. 2003 Sep;22(3):183-98. PMID: 12938083

 Sulis ML, Parsons R. PTEN: from pathology to biology. Trends Cell Biol. 2003 Sep;13(9):478-83. PMID: 12946627

 Wishart MJ, Dixon JE. PTEN and myotubularin phosphatases: from 3-phosphoinositide dephosphorylation to disease. Trends Cell Biol. 2002 Dec;12(12):579-85. PMID: 12495846

 Waite KA, Eng C. Protean PTEN: form and function.
Am J Hum Genet. 2002 Apr;70(4):829-44. PMID: 11875759

 Ali IU. Gatekeeper for endometrium: the PTEN tumor suppressor gene. J Natl Cancer Inst. 2000 Jun 7;92(11):861-3. PMID: 10841815