Gu TL, Goss VL, Reeves C, Popova L, Nardone J, Macneill J et al.. Phosphotyrosine profiling identifies the KG-1 cell line as a model for the study of FGFR1 fusions in acute myeloid leukemia. Blood 108: 4202-4204

Oregon Health and Science University, Portland, Oregon, United States
Blood (Impact Factor: 10.45). 01/2007; 108(13):4202-4. DOI: 10.1182/blood-2006-06-026666
Source: PubMed


The 8p11 myeloproliferative syndrome (EMS) is associated with translocations that disrupt the FGFR1 gene. To date, 8 fusion partners of FGFR1 have been identified. However, no primary leukemia cell lines were identified that contain any of these fusions. Here, we screened more than 40 acute myeloid leukemia cell lines for constitutive phosphorylation of STAT5 and applied an immunoaffinity profiling strategy to identify tyrosine-phosphorylated proteins in the KG-1 cell line. Mass spectrometry analysis of KG-1 cells revealed aberrant tyrosine phosphorylation of FGFR1. Subsequent analysis led to the identification of a fusion of the FGFR1OP2 gene to the FGFR1 gene. Small interfering RNA (siRNA) against FGFR1 specifically inhibited the growth and induced apoptosis of KG-1 cells. Thus, the KG-1 cell line provides an in vitro model for the study of FGFR1 fusions associated with leukemia and for the analysis of small molecule inhibitors against FGFR1 fusions.

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Available from: Michael J Comb
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    • "Interestingly, immunoblotting results show that FGFR1 as a receptor tyrosine kinase is co-localized with PDHK1 and its substrate PDHA1 in mitochondria (Figure 1D right). Moreover, TKI258 treatment significantly decreased phosphorylation levels of PDHA1 at S293 in human myeloid leukemia KG1a cells harboring a FOP2-FGFR1 fusion protein (Gu et al., 2006) (Figure 1E; left) and lung cancer NCI-H1299 cells overexpressing FGFR1 (Marek et al., 2009) (Figure 1E; right). In consonance with this, targeting PDHK1 by a PDHK inhibitor, dichloroacetate (DCA), or shRNA results in decreased S293 phosphorylation levels of PDHA1 in FGFR1-expressing cancer cells (Figure 1F). "
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    • "STAT3-decoy ODN also induced cell death of MCF-7 cells, in which a low but detectable STAT3 activation has been previously observed [42]. However, the STAT3-decoy ODN had no effect on the acute myeloid leukemia cell line KG1, in which STAT5, rather than STAT3, is activated [43] (Figure 4A). The mutated STAT3-decoy ODN had no effect in any of the three cell lines (Figure 4A). "
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    • "Compared to IMAC, PhosphoScan should better dissect phosphorylation profiles, specifically identifying tyrosine-phosphorylated peptides. This approach has already been successfully used in the phospho-profiling of primary [23] and metastatic [24] lung cancer, in acute leukemia samples [25], in Bcr/Abl positive cell lines [26], AML cell lines [27] and Hodgkin lymphoma cell lines [28]. Since tyrosine phosphorylation regulates the activity of many proteins, the PhosphoScan approach can provide a picture of the most active pathways in the analyzed samples. "
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