Functional expression and mutations of c-Met and its therapeutic inhibition with SU11274 and small interfering RNA in non-small cell lung cancer.
Non-small cell lung cancer (NSCLC) is a difficult disease to treat. The c-Met receptor is an attractive potential target for novel therapeutic inhibition in human cancers. We provide strong evidence that c-Met is overexpressed, activated, and sometimes mutated in NSCLC cell lines and tumor tissues. Expression of c-Met was found in all (100%) of the NSCLC tumor tissues examined (n = 23) and most (89%) of the cell lines (n = 9). Sixty-one percent of tumor tissues strongly expressed total c-Met, especially adenocarcinoma (67%). Specific expression of phospho-Met (p-Met) [Y1003] and [Y1230/1234/1235] was seen by immunohistochemistry. p-Met expression was preferentially observed at the NSCLC tumor invasive fronts. c-Met alterations were identified within the semaphorin domain (E168D, L299F, S323G, and N375S) and the juxtamembrane domain (R988C, R988C + T1010I, S1058P, and alternative splice product skipping entire juxtamembrane domain) of a NSCLC cell line and adenocarcinoma tissues. We validated c-Met as potential therapeutic target using small interfering RNA down-regulation of the receptor expression by 50% to 60% in NSCLC cells. This led to inhibition of p-Met and phospho-AKT and up to 57.1 +/- 7.2% cell viability inhibition at 72 hours. The selective small molecule inhibitor of c-Met SU11274 inhibited cell viability in c-Met-expressing NSCLC cells. SU11274 also abrogated hepatocyte growth factor-induced phosphorylation of c-Met and its downstream signaling. Here, we provide first direct evidence by small interfering RNA targeting and small molecule inhibitor that c-Met is important in NSCLC biology and biochemistry. These results indicate that c-Met inhibition will be an important therapeutic strategy against NSCLC to improve its clinical outcome.
Ma
Patrick C
PC
Section of Hematology/Oncology, Department of Medicine, University of Chicago Medical Center, Pritzker School of Medicine, Chicago, Illinois, USA.
Jagadeeswaran
Ramasamy
R
Jagadeesh
Simha
S
Tretiakova
Maria S
MS
Nallasura
Vidya
V
Fox
Edward A
EA
Hansen
Mark
M
Schaefer
Erik
E
Naoki
Katsuhiko
K
Lader
Alan
A
Richards
William
W
Sugarbaker
David
D
Husain
Aliya N
AN
Christensen
James G
JG
Salgia
Ravi
R
D002289:Carcinoma, Non-Small-Cell Lung / Q000188:drug therapy / Q000235:genetics / Q000473:pathology / Q000628:therapy*; D045744:Cell Line, Tumor; D002470:Cell Survival / Q000187:drug effects; D015972:Gene Expression Regulation, Neoplastic; D020868:Gene Silencing; D006801:Humans; D007211:Indoles / Q000494:pharmacology*; D008175:Lung Neoplasms / Q000188:drug therapy / Q000235:genetics / Q000473:pathology / Q000628:therapy*; D009154:Mutation; D010766:Phosphorylation / Q000187:drug effects; D010879:Piperazines / Q000494:pharmacology*; D019859:Proto-Oncogene Proteins c-met / Q000037:antagonists & inhibitors* / Q000096:biosynthesis / Q000235:genetics / Q000378:metabolism; D034741:RNA, Small Interfering / Q000235:genetics*; D015398:Signal Transduction / Q000187:drug effects; 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; D034741:RNA, Small Interfering; D013449:Sulfonamides; D019859:Proto-Oncogene Proteins c-met