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Constitutively activating mutations of c-kit receptor tyrosine kinase confer factor-independent growth and tumorigenicity of factor-dependent hematopoietic cell lines
- Source :
- Blood. 85:790-798
- Publication Year :
- 1995
- Publisher :
- American Society of Hematology, 1995.
-
Abstract
- The c-kit receptor tyrosine kinase (KIT) is activated upon ligand binding, thereby leading to a variety of signaling events that play a fundamental role in hematopoiesis. In addition to ligand-dependent activation, we have previously shown that KIT is constitutively activated in a ligand-independent manner by two point mutations, Val- 559-->Gly (G559) mutation in the juxtamembrane domain and Asp-814-->Val (V814) mutation in the phosphotransferase domain. To investigate the biochemical consequence and biologic significance of these mutations, retroviral vectors encoding KITG559 or KITV814 were introduced into murine pro-B-type Ba/F3 cells and myeloid FDC-P1 cells, both of which require interleukin-3 (IL-3) for their growth and survival. In the cells, KITG559 or KITV814 were found to be constitutively phophorylated on tyrosine in the absence of stem cell factor (SCF) that is a ligand for KIT. Chemical cross-linking analysis showed that a substantial fraction of the phosphorylated KITG559 underwent dimerization even in the absence of SCF, whereas the phosphorylated KITV814 did not, suggesting the distinct mechanisms underlying constitutive activation of KIT by G559 and V814 mutations. Furthermore, the cells expressing either KITG559 or KITV814 were found to show a factor-independent growth, whereas the cells expressing wild-type KIT (KITWT) proliferated in response to SCF as well as IL-3. Moreover, subcutaneous injection of Ba/F3 cells expressing KITG559 or KITV814 into nude mice resulted in production of large tumors at all sites of the injection within 2 weeks, and all nude mice quickly succumbed to leukemia and died. These results suggest that, although the mechanisms underlying constitutive activation of KITG559 or KITV814 may be different, both of the activating mutations have a function to induce a factor-independent and tumorigenic phenotype. Also, the data of this study raise the possibility that the constitutively activating mutations of c-kit may play a causal role in development of hematologic malignancies.
- Subjects :
- Cell Transplantation
Immunology
Mice, Nude
Stem cell factor
Transfection
medicine.disease_cause
Biochemistry
Receptor tyrosine kinase
Cell Line
Mice
Proto-Oncogene Proteins
Proto-Oncogenes
Receptors, Colony-Stimulating Factor
medicine
Animals
Humans
Point Mutation
Amino Acid Sequence
Aspartic Acid
Mice, Inbred BALB C
Mutation
biology
Point mutation
Receptor Protein-Tyrosine Kinases
Valine
Cell Biology
Hematology
Molecular biology
Kinetics
Proto-Oncogene Proteins c-kit
Haematopoiesis
Cell Transformation, Neoplastic
Mutagenesis, Site-Directed
biology.protein
Female
Tyrosine kinase
Cell Division
Subjects
Details
- ISSN :
- 15280020 and 00064971
- Volume :
- 85
- Database :
- OpenAIRE
- Journal :
- Blood
- Accession number :
- edsair.doi.dedup.....ae3be7c8cb17528abeb2a6735b5ae21e