PI3Kα
PI3Kα (p110α), encoded by PIK3CA, is a class IA phosphoinositide 3-kinase catalytic subunit that forms a heterodimer with p85 regulatory proteins and catalyzes the phosphorylation of phosphatidylinositol-(4,5)-bisphosphate to generate phosphatidylinositol-(3,4,5)-trisphosphate, thereby regulating cell growth, proliferation, survival, migration, and metabolic signaling[1][2]. Mechanistically, PI3Kα is a central component of the PI3K-AKT-mTOR signaling axis and functions downstream of receptor tyrosine kinases and RAS proteins to amplify intracellular growth and survival pathways[3][4]. Dysregulation of this pathway is among the most common molecular events in human cancer, and activating mutations in PIK3CA promote tumor initiation, progression, and therapeutic resistance through sustained PI3K signaling[3][5]. In disease models, disruption of the RAS-PI3Kα interaction suppresses tumor growth and angiogenesis, highlighting the importance of PI3Kα-dependent signaling in oncogenic processes[4]. Compared with related class I PI3K isoforms, p110α and p110β are broadly expressed across tissues, whereas p110δ is predominantly expressed in leukocytes, indicating distinct physiological functions and therapeutic opportunities among isoforms[6]. Furthermore, PTEN-deficient tumors frequently depend on p110β activity, emphasizing a biologically important distinction between PI3Kα- and PI3Kβ-driven signaling networks[2]. For experimental and translational applications, isoform-selective PI3Kα inhibitors, including alpelisib, have been developed to target PIK3CA-driven malignancies, making PI3Kα a major focus of precision oncology research[5].
References:
- [1]. PI3Kα gene information from NCBI.
- [2]. Mazloumi Gavgani F, et al. Class I Phosphoinositide 3-Kinase PIK3CA/p110α and PIK3CB/p110β Isoforms in Endometrial Cancer. Int J Mol Sci. 2018 Dec 7;19(12):3931. [Content Brief]
- [3]. Wang Y, et al. Oncogenic activation of PIK3CA in cancers: Emerging targeted therapies in precision oncology. Genes Dis. 2024 Sep 10;12(2):101430. [Content Brief]
- [4]. Czyzyk D, et al. Structural insights into isoform-specific RAS-PI3Kα interactions and the role of RAS in PI3Kα activation. Nat Commun. 2025 Jan 9;16(1):525. [Content Brief]
- [5]. Thorpe LM, et al. PI3K in cancer: divergent roles of isoforms, modes of activation and therapeutic targeting. Nat Rev Cancer. 2015 Jan;15(1):7-24. [Content Brief]
- [6]. Wikipedia.
- [7]. Wikipedia.
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PI3Kα Related Products (236)
Related Products (236)
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Copanlisib dihydrochloride
0 ImagesSynonyms: BAY 80-6946 dihydrochlorideCopanlisib dihydrochloride (BAY 80-6946 dihydrochloride) is a potent, selective and ATP-competitive pan-class I PI3K inhibitor, with IC50s of 0.5 nM, 0.7 nM, 3.7 nM and 6.4 nM for PI3Kα, PI3Kδ, PI3Kβ and PI3Kγ, respectively. Copanlisib dihydrochloride has more than 2,000-fold selectivity against other lipid and protein kinases, except for mTOR. Copanlisib dihydrochloride has superior antitumor activity.
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Samotolisib
0 ImagesSynonyms: LY3023414Samotolisib (LY3023414) potently and selectively inhibits class I PI3K isoforms, DNA-PK, and mTORC1/2 with IC50s of 6.07 nM, 77.6 nM, 38 nM, 23.8 nM, 4.24 nM and 165 nM for PI3Kα, PI3Kβ, PI3Kδ, PI3Kγ, DNA-PK and mTOR, respectively. Samotolisib potently inhibits mTORC1/2 at low nanomolar concentrations.
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Apitolisib
0 ImagesSynonyms: GDC-0980; GNE 390; RG 7422
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Umbralisib
0 ImagesSynonyms: TGR-1202; RP5264Umbralisib (TGR-1202) is an orally active, potent and selective dual PI3Kδ and casein kinase-1-ε (CK1ε) inhibitor, with EC50 of 22.2 nM and 6.0 μM, respectively. Umbralisib exhibits unique immunomodulatory effects on chronic lymphocytic leukemia (CLL) T cells. Umbralisib can be used for haematological malignancies reseach.
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Vps34-PIK-III
0 ImagesVps34-PIK-III is an orally active and selective VPS34 inhibitor (IC50=18 nM). Vps34-PIK-III effectively inhibits autophagy and can be used as a molecular tool. vps34-PIK-III is also a PI3K inhibitor that inhibits the expression of genes in liver cancer stem cells (CSCs).
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Dactolisib Tosylate
0 ImagesSynonyms: BEZ235 Tosylate; NVP-BEZ 235 Tosylate
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D927
0 ImagesSynonyms: DS11252927D927 (DS11252927) is an orally active glucose transporter type 4 (GLUT4) translocation activator with an EC50 of 0.14 μM. D927 enhances the binding affinity of PI3Kα catalytic subunit p110α to canonical RAS proteins (KRAS4A, KRAS4B) and RRAS, RRAS2, MRAS. D927 activates the PI3Kα-AKT pathway (increasing phosphorylation of AKT, p70S6 kinase) without affecting the RAF-ERK1/2 pathway. D927 improves hyperglycemia in type 1 and type 2 diabetes mice model. D927 can be used for the study of glucose homeostasis disorders and diabetes.
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MTX-531
0 ImagesMTX-531 is an oral drug that inhibits EGFR (with an IC50 of 14.7 nM) and PI3K (with IC50 values of 6.4, 233, 8.3, and 1.1 nM for PI3Kα, PI3Kβ, PI3Kγ, and PI3Kδ respectively), and it has anti-tumor effects. MTX-531 also acts as a weak agonist of PPARγ, with an IC50 of 2.5 µM, helping to alleviate hyperglycemia induced by PI3K inhibitors.
