BACKGROUND & AIMS: The c-kit gene encodes a receptor tyrosine kinase (KIT). Recently, we found gain-of-function mutations of the c-kit gene in gastrointestinal stromal tumors (GISTs). All mutations were confined within the 11 amino acids (Lys-550 to Val-560) in the juxtamembrane domain, but one GIST showed a novel deletion-type mutation at codon 579 (Asp) in the juxtamembrane domain. The aim of this study was to clarify whether the mutation is activating. METHODS: Mutant c-kit cDNA was transfected into an interleukin 3 (IL-3)-dependent Ba/F3 murine lymphoid cell line, and the magnitude of autophosphorylation of the mutant KIT was examined with or without stem cell factor (SCF), a ligand of KIT. An in vitro kinase assay was also performed. The biological behavior of the transfectant was estimated by both an in vitro proliferation assay and in vivo transplantation to nude mice. RESULTS: The mutant KIT exhibited constitutive phosphorylation and strong kinase activity without SCF. The transfectant grew autonomously without IL-3 and SCF, and it formed tumors in nude mice. CONCLUSIONS: Deletion at codon 579 (Asp) in the juxtamembrane domain of the c-kit gene is a novel gain-of-function mutation other than the region between Lys-550 and Val-560.
BACKGROUND & AIMS: The c-kit gene encodes a receptor tyrosine kinase (KIT). Recently, we found gain-of-function mutations of the c-kit gene in gastrointestinal stromal tumors (GISTs). All mutations were confined within the 11 amino acids (Lys-550 to Val-560) in the juxtamembrane domain, but one GIST showed a novel deletion-type mutation at codon 579 (Asp) in the juxtamembrane domain. The aim of this study was to clarify whether the mutation is activating. METHODS: Mutant c-kit cDNA was transfected into an interleukin 3 (IL-3)-dependent Ba/F3 murine lymphoid cell line, and the magnitude of autophosphorylation of the mutant KIT was examined with or without stem cell factor (SCF), a ligand of KIT. An in vitro kinase assay was also performed. The biological behavior of the transfectant was estimated by both an in vitro proliferation assay and in vivo transplantation to nude mice. RESULTS: The mutant KIT exhibited constitutive phosphorylation and strong kinase activity without SCF. The transfectant grew autonomously without IL-3 and SCF, and it formed tumors in nude mice. CONCLUSIONS: Deletion at codon 579 (Asp) in the juxtamembrane domain of the c-kit gene is a novel gain-of-function mutation other than the region between Lys-550 and Val-560.
Authors: B Lawrence; A Perez-Atayde; M K Hibbard; B P Rubin; P Dal Cin; J L Pinkus; G S Pinkus; S Xiao; E S Yi; C D Fletcher; J A Fletcher Journal: Am J Pathol Date: 2000-08 Impact factor: 4.307
Authors: Justin M Drake; Nicholas A Graham; Tanya Stoyanova; Amir Sedghi; Andrew S Goldstein; Houjian Cai; Daniel A Smith; Hong Zhang; Evangelia Komisopoulou; Jiaoti Huang; Thomas G Graeber; Owen N Witte Journal: Proc Natl Acad Sci U S A Date: 2012-01-17 Impact factor: 11.205
Authors: M L Lux; B P Rubin; T L Biase; C J Chen; T Maclure; G Demetri; S Xiao; S Singer; C D Fletcher; J A Fletcher Journal: Am J Pathol Date: 2000-03 Impact factor: 4.307
Authors: Tanya M Laidlaw; John W Steinke; Adrienne M Tiñana; Chunli Feng; Wei Xing; Bing K Lam; Sailaja Paruchuri; Joshua A Boyce; Larry Borish Journal: J Allergy Clin Immunol Date: 2011-02-01 Impact factor: 10.793