Missing content? – Request curation!
Request curation for specific Genes, Variants, or PubMed publications.
Have questions, comments, or suggestions? - Let us know!
Email us at : ckbsupport@genomenon.com
| Ref Type | Journal Article | ||||||||||||
| PMID | (19276253) | ||||||||||||
| Authors | Reindl C, Quentmeier H, Petropoulos K, Greif PA, Benthaus T, Argiropoulos B, Mellert G, Vempati S, Duyster J, Buske C, Bohlander SK, Humphries KR, Hiddemann W, Spiekermann K | ||||||||||||
| Title | CBL exon 8/9 mutants activate the FLT3 pathway and cluster in core binding factor/11q deletion acute myeloid leukemia/myelodysplastic syndrome subtypes. | ||||||||||||
|
|||||||||||||
| URL | |||||||||||||
| Abstract Text | CBL is a negative regulator of activated receptor tyrosine kinases (RTK). In this study, we determined the frequency of CBL mutations in acute leukemias and evaluated the oncogenic potential of mutant CBL.The cDNA of 300 acute myeloid leukemia (AML)/myelodysplastic syndrome (MDS) and acute lymphoblastic leukemia (ALL) patients and 82 human leukemic cell lines was screened for aberrations in the linker and RING finger domain of CBL. The oncogenic potential of identified mutants was evaluated in hematopoietic cells.We identified 3 of 279 AML/MDS patients expressing CBL exon 8/9 deletion mutants. Three of four cases at diagnosis expressed deleted transcripts missing exon 8 or exon 8/9. In remission samples a weak or no expression of mutant CBL was detected. No aberrations were found in normal hematopoietic tissues. One of 116 sequenced AML/MDS cases carried a R420G missense mutation. All AML/MDS patients with identified CBL mutants belonged to the core binding factor and 11q deletion AML subtypes. Functionally, CBL negatively regulated FMS-like tyrosine kinase 3 (FLT3) activity and interacted with human FLT3 via the autophosphorylation sites Y589 and Y599 and colocalized in vivo. Expression of CBLDeltaexon8 and CBLDeltaexon8+9 in FLT3-WT-Ba/F3 cells induced growth factor-independent proliferation associated with autophosphorylation of FLT3 and activated the downstream targets signal transducer and activator of transcription 5 (STAT5) and protein kinase B (AKT). FLT3 ligand-dependent hyperproliferation of CBL mutant cells could be abrogated by treatment with the FLT3 PTK inhibitor PKC412 (midostaurin).CBL exon8/9 mutants occur in genetically defined AML/MDS subtypes and transform hematopoietic cells by constitutively activating the FLT3 pathway. This phenotype resembles the one of mutated RTKs and suggests that CBL mutant AML patients might benefit from treatment with FLT3 PTK inhibitors. | ||||||||||||
| Gene Name | Source | Synonyms | Protein Domains | Gene Description | Gene Role |
|---|
| Therapy Name | Drugs | Efficacy Evidence | Clinical Trials |
|---|
| Drug Name | Trade Name | Synonyms | Drug Classes | Drug Description |
|---|
| Gene | Variant | Impact | Protein Effect | Variant Description | Associated with drug Resistance |
|---|---|---|---|---|---|
| CBL | del exon8 | deletion | gain of function | CBL del exon8 is a CBL splice variant caused by a mutation resulting in the deletion of exon 8 (PMID: 18698078). Del exon8 results in ligand-independent Flt3 autophosphorylation, and activation of Stat5 and Akt, and leads to increased ligand-dependent proliferation, and IL-3 independent proliferation of cells in culture (PMID: 19276253). | |
| CBL | del exon9 | deletion | loss of function | CBL del exon9 is a CBL splice variant caused by a mutation resulting in the deletion of exon 9 (PMID: 19276253). Del exon9 demonstrates increased ubiquitination and reduced protein stability of Cbl, and failure to suppress Erk phosphorylation in cell culture (PMID: 26152360). |
| Molecular Profile | Indication/Tumor Type | Response Type | Therapy Name | Approval Status | Evidence Type | Efficacy Evidence | References |
|---|