Discovery of a novel class of AKT pleckstrin homology domain inhibitors.
AKT, a phospholipid-binding serine/threonine kinase, is a key component of the phosphoinositide 3-kinase cell survival signaling pathway that is aberrantly activated in many human cancers. Many attempts have been made to inhibit AKT; however, selectivity remains to be achieved. We have developed a novel strategy to inhibit AKT by targeting the pleckstrin homology (PH) domain. Using in silico library screening and interactive molecular docking, we have identified a novel class of non-lipid-based compounds that bind selectively to the PH domain of AKT, with "in silico" calculated K(D) values ranging from 0.8 to 3.0 micromol/L. In order to determine the selectivity of these compounds for AKT, we used surface plasmon resonance to measure the binding characteristics of the compounds to the PH domains of AKT1, insulin receptor substrate-1, and 3-phosphoinositide-dependent protein kinase 1. There was excellent correlation between predicted in silico and measured in vitro K(D)s for binding to the PH domain of AKT, which were in the range 0.4 to 3.6 micromol/L. Some of the compounds exhibited PH domain-binding selectivity for AKT compared with insulin receptor substrate-1 and 3-phosphoinositide-dependent protein kinase 1. The compounds also inhibited AKT in cells, induced apoptosis, and inhibited cancer cell proliferation. In vivo, the lead compound failed to achieve the blood concentrations required to inhibit AKT in cells, most likely due to rapid metabolism and elimination, and did not show antitumor activity. These results show that these compounds are the first small molecules selectively targeting the PH domain of AKT.
Mahadevan
Daruka
D
College of Medicine, Arizona Cancer Center, University of Arizona, Tucson, AZ 85721-0038, USA.
Powis
Garth
G
Mash
Eugene A
EA
George
Benjamin
B
Gokhale
Vijay M
VM
Zhang
Shuxing
S
Shakalya
Kishore
K
Du-Cuny
Lei
L
Berggren
Margareta
M
Ali
M Ahad
MA
Jana
Umasish
U
Ihle
Nathan
N
Moses
Sylvestor
S
Franklin
Chloe
C
Narayan
Satya
S
Shirahatti
Nikhil
N
Meuillet
Emmanuelle J
EJ
D048868:Adaptor Proteins, Signal Transducing / Q000037:antagonists & inhibitors; D000595:Amino Acid Sequence; D000818:Animals; D000970:Antineoplastic Agents / Q000138:chemical synthesis / Q000737:chemistry / Q000493:pharmacokinetics / Q000494:pharmacology; D001667:Binding, Competitive / Q000187:drug effects; D015195:Drug Design; D004354:Drug Screening Assays, Antitumor; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D019073:HT29 Cells; D006801:Humans; D055504:Insulin Receptor Substrate Proteins; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D016513:Mice, SCID; D008969:Molecular Sequence Data; D017434:Protein Structure, Tertiary; D051057:Proto-Oncogene Proteins c-akt / Q000037:antagonists & inhibitors* / Q000737:chemistry*; D016415:Sequence Alignment; D013846:Thiepins / Q000138:chemical synthesis / Q000737:chemistry / Q000493:pharmacokinetics / Q000494:pharmacology*
D048868:Adaptor Proteins, Signal Transducing; D000970:Antineoplastic Agents; C526292:IRS1 protein, human; D055504:Insulin Receptor Substrate Proteins; C526295:Irs1 protein, mouse; D013846:Thiepins; D051057:Proto-Oncogene Proteins c-akt
J Biol Chem. 1998 Dec 4;273(49):32377-9
9829964
EMBO J. 2004 Oct 13;23(20):3918-28
15457207
Science. 1998 Nov 13;282(5392):1318-21
9812896
Biochemistry. 1995 Jul 18;34(28):9111-7
7619809
FEBS Lett. 2003 Jul 3;546(1):108-12
12829245
Oncogene. 2005 Nov 14;24(50):7493-501
16288296
Curr Opin Investig Drugs. 2005 Dec;6(12):1250-8
16370391
Proc Natl Acad Sci U S A. 1999 Jul 20;96(15):8378-83
10411883
J Biol Chem. 2003 Aug 22;278(34):32124-31
12783884
J Biol Chem. 1998 May 22;273(21):13150-6
9582355
J Biol Chem. 1998 May 29;273(22):13375-8
9593664
Curr Opin Genet Dev. 1998 Feb;8(1):55-62
9529606
Cancer Res. 2000 Mar 15;60(6):1541-5
10749120
Mol Cell Biol. 2001 Feb;21(3):893-901
11154276
Trends Biochem Sci. 1997 Sep;22(9):355-8
9301337
Cancer Metastasis Rev. 2001;20(1-2):79-86
11831651
J Biol Chem. 1994 Apr 8;269(14):10217-20
8144601
PLoS Biol. 2007 Apr;5(4):e95
17407381
Proc Natl Acad Sci U S A. 1999 Apr 13;96(8):4240-5
10200246
Nat Rev Drug Discov. 2005 Dec;4(12):988-1004
16341064
Cell. 1997 Oct 17;91(2):231-41
9346240
Nat Rev Mol Cell Biol. 2001 Oct;2(10):760-8
11584303
Annu Rev Biophys Biomol Struct. 1998;27:503-28
9646876
J Biol Chem. 1999 Jul 30;274(31):21528-32
10419456
Oncol Res. 2004;14(10):513-27
15559765
Proc Natl Acad Sci U S A. 1998 Sep 15;95(19):11211-6
9736715
Cell Signal. 2002 May;14(5):381-95
11882383
Nat Biotechnol. 2006 Jul;24(7):794-6
16841064
Biochem J. 2001 Jun 1;356(Pt 2):481-6
11368775
Cancer Chemother Pharmacol. 1997;40(3):209-14
9219503
Cell. 2000 Mar 17;100(6):603-6
10761925
Biochem J. 1998 Oct 1;335 ( Pt 1):1-13
9742206
J Biol Chem. 2004 Nov 12;279(46):47720-5
15364915
Exp Hematol. 2007 Jul;35(7):1038-46
17588472
Curr Biol. 1997 Apr 1;7(4):261-9
9094314
Mol Cancer Ther. 2006 Mar;5(3):713-22
16546986
Nature. 1999 Sep 2;401(6748):82-5
10485710
Mol Cancer Ther. 2003 Apr;2(4):389-99
12700283
Nature. 1994 Jul 7;370(6484):71-5
8015612
Nature. 2007 Jul 26;448(7152):439-44
17611497
Cancer Res. 2004 Apr 15;64(8):2782-92
15087394
J Comput Aided Mol Des. 2002 Jan;16(1):11-26
12197663
Science. 2005 Feb 18;307(5712):1098-101
15718470
J Biol Chem. 1997 Nov 28;272(48):30491-7
9374542
Curr Biol. 2002 Jul 23;12(14):1256-62
12176338
Proc Natl Acad Sci U S A. 1998 Dec 22;95(26):15587-91
9861013