A class of highly selective inhibitors bind to an active state of PI3Kγ.
Nat Chem Biol
; 15(4): 348-357, 2019 04.
Article
in En
| MEDLINE
| ID: mdl-30718815
ABSTRACT
We have discovered a class of PI3Kγ inhibitors exhibiting over 1,000-fold selectivity over PI3Kα and PI3Kß. On the basis of X-ray crystallography, hydrogen-deuterium exchange-mass spectrometry and surface plasmon resonance experiments we propose that the cyclopropylethyl moiety displaces the DFG motif of the enzyme away from the adenosine tri-phosphate binding site, inducing a large conformational change in both the kinase- and helical domains of PI3Kγ. Site directed mutagenesis explained how the conformational changes occur. Our results suggest that these cyclopropylethyl substituted compounds selectively inhibit the active state of PI3Kγ, which is unique to these compounds and to the PI3Kγ isoform, explaining their excellent potency and unmatched isoform selectivity that were confirmed in cellular systems. This is the first example of a Class I PI3K inhibitor achieving its selectivity by affecting the DFG motif in a manner that bears similarity to DFG in/out for type II protein kinase inhibitors.
Full text:
1
Database:
MEDLINE
Main subject:
Phosphatidylinositol 3-Kinases
/
Class Ib Phosphatidylinositol 3-Kinase
/
Phosphoinositide-3 Kinase Inhibitors
Limits:
Humans
Language:
En
Journal:
Nat Chem Biol
Journal subject:
BIOLOGIA
/
QUIMICA
Year:
2019
Type:
Article
Affiliation country:
Sweden