Disruption of the EGFR E884-R958 ion pair conserved in the human kinome differentially alters signaling and inhibitor sensitivity.
Targeted therapy against epidermal growth factor receptor (EGFR) represents a major therapeutic advance in lung cancer treatment. Somatic mutations of the EGFR gene, most commonly L858R (exon 21) and short in-frame exon 19 deletions, have been found to confer enhanced sensitivity toward the inhibitors gefitinib and erlotinib. We have recently identified an EGFR mutation E884K, in combination with L858R, in a patient with advanced lung cancer who progressed on erlotinib maintenance therapy, and subsequently had leptomeningeal metastases that responded to gefitinib. The somatic E884K substitution appears to be relatively infrequent and resulted in a mutant lysine residue that disrupts an ion pair with residue R958 in the EGFR kinase domain C-lobe, an interaction that is highly conserved within the human kinome as demonstrated by our sequence analysis and structure analysis. Our studies here, using COS-7 transfection model system, show that E884K works in concert with L858R in-cis, in a dominant manner, to change downstream signaling, differentially induce Mitogen-activated protein kinase (extracellular signaling-regulated kinase 1/2) signaling and associated cell proliferation and differentially alter sensitivity of EGFR phosphorylation inhibition by ERBB family inhibitors in an inhibitor-specific manner. Mutations of the conserved ion pair E884-R958 may result in conformational changes that alter kinase substrate recognition. The analogous E1271K-MET mutation conferred differential sensitivity toward preclinical MET inhibitors SU11274 (unchanged) and PHA665752 (more sensitive). Systematic bioinformatics analysis of the mutation catalog in the human kinome revealed the presence of cancer-associated mutations involving the conserved E884 homologous residue, and adjacent residues at the ion pair, in known proto-oncogenes (KIT, RET, MET and FAK) and tumor-suppressor gene (LKB1). Targeted therapy using small-molecule inhibitors should take into account potential cooperative effects of multiple kinase mutations, and their specific effects on downstream signaling and inhibitor sensitivity. Improved efficacy of targeted kinase inhibitors may be achieved by targeting the dominant activating mutations present.
Tang
Z
Z
Division of Hematology/Oncology, Case Western Reserve University School of Medicine, University Hospitals Case Medical Center and Ireland Cancer Center, Case Comprehensive Cancer Center, Cleveland, OH 44106, USA.
Jiang
S
S
Du
R
R
Petri
E T
ET
El-Telbany
A
A
Chan
P S O
PS
Kijima
T
T
Dietrich
S
S
Matsui
K
K
Kobayashi
M
M
Sasada
S
S
Okamoto
N
N
Suzuki
H
H
Kawahara
K
K
Iwasaki
T
T
Nakagawa
K
K
Kawase
I
I
Christensen
J G
JG
Hirashima
T
T
Halmos
B
B
Salgia
R
R
Boggon
T J
TJ
Kern
J A
JA
Ma
P C
PC
D000091162:AMP-Activated Protein Kinase Kinases; D019943:Amino Acid Substitution; D000818:Animals; D019556:COS Cells; D002522:Chlorocebus aethiops; D066246:ErbB Receptors / Q000037:antagonists & inhibitors / Q000235:genetics* / Q000378:metabolism*; D000069347:Erlotinib Hydrochloride; D051417:Focal Adhesion Kinase 1 / Q000037:antagonists & inhibitors / Q000235:genetics / Q000378:metabolism; D006801:Humans; D007211:Indoles / Q000494:pharmacology; D008175:Lung Neoplasms / Q000188:drug therapy / Q000201:enzymology* / Q000235:genetics* / Q000473:pathology; D020935:MAP Kinase Signaling System / Q000187:drug effects / Q000235:genetics*; D019950:Mitogen-Activated Protein Kinase 1 / Q000037:antagonists & inhibitors / Q000235:genetics / Q000378:metabolism; D048052:Mitogen-Activated Protein Kinase 3 / Q000037:antagonists & inhibitors / Q000235:genetics / Q000378:metabolism; D020125:Mutation, Missense; D010879:Piperazines / Q000494:pharmacology; D011487:Protein Conformation; D047428:Protein Kinase Inhibitors / Q000494:pharmacology / Q000627:therapeutic use; D017346:Protein Serine-Threonine Kinases / Q000037:antagonists & inhibitors / Q000235:genetics / Q000378:metabolism; D011518:Proto-Oncogene Proteins / Q000037:antagonists & inhibitors / Q000235:genetics / Q000378:metabolism; D019009:Proto-Oncogene Proteins c-kit / Q000235:genetics / Q000378:metabolism; D019859:Proto-Oncogene Proteins c-met; D051096:Proto-Oncogene Proteins c-ret / Q000037:antagonists & inhibitors / Q000235:genetics / Q000378:metabolism; D011799:Quinazolines / Q000494:pharmacology / Q000627:therapeutic use; D017978:Receptors, Growth Factor / Q000037:antagonists & inhibitors / Q000235:genetics / Q000378:metabolism; D013449:Sulfonamides / Q000494:pharmacology
C478479:((3Z)-N-(3-chlorophenyl)-3-((3,5-dimethyl-4-((4-methylpiperazin-1-yl)carbonyl)-1H-pyrrol-2-yl)methylene)-N-methyl-2-oxo-2,3-dihydro-1H-indole-5-sulfonamide); D007211:Indoles; D010879:Piperazines; D047428:Protein Kinase Inhibitors; D011518:Proto-Oncogene Proteins; D011799:Quinazolines; D017978:Receptors, Growth Factor; D013449:Sulfonamides; D000069347:Erlotinib Hydrochloride; C512478:EGFR protein, human; D066246:ErbB Receptors; C491743:MET protein, human; D019009:Proto-Oncogene Proteins c-kit; D019859:Proto-Oncogene Proteins c-met; D051096:Proto-Oncogene Proteins c-ret; C099282:RET protein, human; D051417:Focal Adhesion Kinase 1; C496050:PTK2 protein, human; D017346:Protein Serine-Threonine Kinases; C109790:STK11 protein, human; D019950:Mitogen-Activated Protein Kinase 1; D048052:Mitogen-Activated Protein Kinase 3; D000091162:AMP-Activated Protein Kinase Kinases