PI3K/AKT/mTOR pathway: Difference between revisions

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'''PI3K/AKT/mTOR pathway''' is a critical cell signaling pathway that regulates several cellular processes, including cell growth, proliferation, and survival. This pathway is often dysregulated in various diseases, particularly in cancer, making it a significant target for therapeutic intervention.
{{DISPLAYTITLE:PI3K/AKT/mTOR pathway}}


== Overview ==
== Overview ==
The '''PI3K/AKT/mTOR pathway''' is initiated by the binding of a growth factor to its receptor tyrosine kinase (RTK). This binding activates phosphatidylinositol 3-kinase (PI3K), which phosphorylates and activates AKT, a serine/threonine kinase. AKT then activates the mammalian target of rapamycin (mTOR), a key regulator of cell growth and proliferation.  
The '''PI3K/AKT/mTOR pathway''' is a critical signaling pathway that regulates various cellular processes, including growth, proliferation, survival, and metabolism. This pathway is frequently activated in cancer and is a target for therapeutic intervention.


== Components ==
[[File:MTOR-pathway-v1.7.svg|thumb|right|Diagram of the PI3K/AKT/mTOR pathway.]]
=== [[Phosphatidylinositol 3-kinase|PI3K]] ===
PI3K is a lipid kinase that phosphorylates phosphatidylinositol 4,5-bisphosphate (PIP2) to generate phosphatidylinositol 3,4,5-trisphosphate (PIP3). PIP3 serves as a second messenger that recruits AKT to the plasma membrane.


=== [[AKT]] ===
== Components of the Pathway ==
AKT, also known as Protein Kinase B (PKB), is a serine/threonine kinase that is activated by PI3K. Once activated, AKT phosphorylates a variety of substrates involved in cell survival, growth, and proliferation.


=== [[mTOR]] ===
=== Phosphoinositide 3-kinases (PI3K) ===
mTOR is a serine/threonine kinase that regulates cell growth, proliferation, and survival. It is the target of the immunosuppressive drug rapamycin.
[[Phosphoinositide 3-kinases]] (PI3K) are a family of enzymes involved in cellular functions such as cell growth, proliferation, differentiation, motility, and survival. PI3K is activated by various growth factors and hormones, leading to the production of phosphatidylinositol (3,4,5)-trisphosphate (PIP3).


== Role in Disease ==
=== AKT ===
Dysregulation of the PI3K/AKT/mTOR pathway is often observed in various diseases, particularly in cancer. Mutations in PI3K, AKT, or mTOR can lead to constitutive activation of the pathway, promoting cell survival and proliferation and contributing to tumorigenesis.
[[AKT]] (also known as protein kinase B) is a serine/threonine-specific protein kinase that plays a key role in multiple cellular processes. Once activated by PIP3, AKT phosphorylates a range of downstream targets involved in cell survival and metabolism.


== Therapeutic Target ==
=== Mammalian Target of Rapamycin (mTOR) ===
Given its critical role in cell growth and survival, the PI3K/AKT/mTOR pathway is a significant target for therapeutic intervention. Several inhibitors targeting different components of this pathway are currently in clinical trials for the treatment of various cancers.
The [[mammalian target of rapamycin]] (mTOR) is a central regulator of cell metabolism, growth, proliferation, and survival. mTOR forms two distinct complexes: mTORC1 and mTORC2, each with unique roles in the cell.


== See Also ==
== Pathway Activation ==
The PI3K/AKT/mTOR pathway is activated by various extracellular signals, including growth factors like [[insulin]] and [[insulin-like growth factor 1]] (IGF-1). Upon activation, PI3K converts PIP2 to PIP3, which recruits AKT to the plasma membrane where it is phosphorylated and activated. Activated AKT then phosphorylates and regulates a variety of downstream targets, including mTOR.
 
== Role in Cancer ==
The PI3K/AKT/mTOR pathway is often dysregulated in cancer, leading to increased cell growth and survival. Mutations in genes encoding components of this pathway, such as [[PIK3CA]], [[PTEN]], and [[AKT1]], are common in various cancers. Targeting this pathway with specific inhibitors is a major focus of cancer therapy research.
 
== Therapeutic Targeting ==
Inhibitors of the PI3K/AKT/mTOR pathway are being developed and tested in clinical trials for their potential to treat cancer. These include PI3K inhibitors, AKT inhibitors, and mTOR inhibitors such as [[rapamycin]] and its analogs (rapalogs).
 
== Related Pages ==
* [[Signal transduction]]
* [[Signal transduction]]
* [[Cell cycle]]
* [[Apoptosis]]
* [[Cancer]]
* [[Cancer]]
* [[Phosphatidylinositol 3-kinase]]
* [[AKT]]
* [[mTOR]]


[[Category:Signal transduction]]
[[Category:Cell biology]]
[[Category:Cell biology]]
[[Category:Signal transduction]]
[[Category:Cancer research]]
[[Category:Cancer]]
[[Category:Pharmacology]]
 
{{pharmacology-stub}}

Latest revision as of 06:42, 16 February 2025


Overview[edit]

The PI3K/AKT/mTOR pathway is a critical signaling pathway that regulates various cellular processes, including growth, proliferation, survival, and metabolism. This pathway is frequently activated in cancer and is a target for therapeutic intervention.

File:MTOR-pathway-v1.7.svg
Diagram of the PI3K/AKT/mTOR pathway.

Components of the Pathway[edit]

Phosphoinositide 3-kinases (PI3K)[edit]

Phosphoinositide 3-kinases (PI3K) are a family of enzymes involved in cellular functions such as cell growth, proliferation, differentiation, motility, and survival. PI3K is activated by various growth factors and hormones, leading to the production of phosphatidylinositol (3,4,5)-trisphosphate (PIP3).

AKT[edit]

AKT (also known as protein kinase B) is a serine/threonine-specific protein kinase that plays a key role in multiple cellular processes. Once activated by PIP3, AKT phosphorylates a range of downstream targets involved in cell survival and metabolism.

Mammalian Target of Rapamycin (mTOR)[edit]

The mammalian target of rapamycin (mTOR) is a central regulator of cell metabolism, growth, proliferation, and survival. mTOR forms two distinct complexes: mTORC1 and mTORC2, each with unique roles in the cell.

Pathway Activation[edit]

The PI3K/AKT/mTOR pathway is activated by various extracellular signals, including growth factors like insulin and insulin-like growth factor 1 (IGF-1). Upon activation, PI3K converts PIP2 to PIP3, which recruits AKT to the plasma membrane where it is phosphorylated and activated. Activated AKT then phosphorylates and regulates a variety of downstream targets, including mTOR.

Role in Cancer[edit]

The PI3K/AKT/mTOR pathway is often dysregulated in cancer, leading to increased cell growth and survival. Mutations in genes encoding components of this pathway, such as PIK3CA, PTEN, and AKT1, are common in various cancers. Targeting this pathway with specific inhibitors is a major focus of cancer therapy research.

Therapeutic Targeting[edit]

Inhibitors of the PI3K/AKT/mTOR pathway are being developed and tested in clinical trials for their potential to treat cancer. These include PI3K inhibitors, AKT inhibitors, and mTOR inhibitors such as rapamycin and its analogs (rapalogs).

Related Pages[edit]