Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UMLS:C0023473 (chronic myeloid leukemia)
 18,916 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Imatinib mesylate is a potent and specific tyrosine kinase inhibitor against c-ABL, BCR-ABL, and c-KIT, and has been demonstrated to be highly active in chronic myeloid leukemia and gastrointestinal stromal tumors. We examined the antifibrotic effects of imatinib using a bleomycin-induced lung fibrosis model in mice because imatinib also inhibits tyrosine kinase of platelet-derived growth factor receptors (PDGFRs). Imatinib inhibited the growth of primary murine lung fibroblasts and the autophosphorylation of PDGFR-beta induced by PDGF. Administration of imatinib significantly prevented bleomycin-induced pulmonary fibrosis in mice, partly by reducing the number of mesenchymal cells incorporating bromodeoxyuridine. Analysis of bronchoalveolar lavage cells demonstrated that imatinib did not suppress early inflammation on Days 7 and 14 caused by bleomycin. These results suggest that imatinib has the potential to prevent pulmonary fibrosis by inhibiting the proliferation of mesenchymal cells, and that imatinib might be useful for the treatment of pulmonary fibrosis in humans.
 ...
PMID:Imatinib as a novel antifibrotic agent in bleomycin-induced pulmonary fibrosis in mice. 1573 62

In order to identify small regions of the genome whose specific copy number alteration is associated with high genomic instability in the form of overall genome-wide copy number aberrations, we have analyzed array-based comparative genomic hybridization (aCGH) data from 33 sporadic colorectal carcinomas. Copy number changes of a small number of specific regions were significantly correlated with elevated overall amplifications and deletions scattered throughout the entire genome. One significant region at 9q34 includes the c-ABL gene. Another region spanning 22q11-q13 includes the breakpoint cluster region (BCR) of the Philadelphia chromosome. Coordinate 22q11-q13 alterations were observed in 9 of 11 tumors with the 9q34 alteration. Additional regions on 1q and 14q were associated with overall genome-wide copy number changes, while copy number aberrations on chromosome 7p, 7q, and 13q21.1-q31.3 were found associated with this instability only in tumors from patients with a smoking history. Our analysis demonstrates there are a small number of regions of the genome where gain or loss is commonly associated with a tumor's overall level of copy number aberrations. Our finding BCR and ABL located within two of the instability-associated regions, and the involvement of these two regions occurring coordinately, suggests a system akin to the BCR-ABL translocation of CML may be involved in genomic instability in about one-third of human colorectal carcinomas.
 ...
PMID:aCGH local copy number aberrations associated with overall copy number genomic instability in colorectal cancer: coordinate involvement of the regions including BCR and ABL. 1719 95

The phenylaminopyrimidine-derivate Imatinib mesylate has been developed for targeted inhibition of the Abelson kinase (c-ABL), which is constitutively activated when translocated to the genetic locus of the breakpoint cluster region (leading to the BCR/ABL fusion gene), thereby forming the causative pathogenetic event for the development of chronic myeloid leukemia (CML). Of note, due to its physico-chemical properties, kinase specificity of Imatinib is limited. Despite of its well documented clinical efficacy mediated by inhibition of constitutively activated tyrosine kinases such as BCR/ABL in CML, PDGF-RA in HES and mutated c-kit in GIST patients, other tyrosine kinases such as Flt-3, Lck and mitogen-activated kinases (MAPK) are affected as well. Accordingly, it has recently been shown that therapeutic doses of Imatinib also target a variety of immune cells, e.g. by modulating the differentiation of dendritic cells (DC) as well as by impeding proper T-cell and macrophage function. In contrast, combining Imatinib with Interleukin 2 (IL-2) potently activates NK-cells and led to the description of a new subclass of DC, so-called IK-DC. The latter mediate Imatinib/IL-2-induced regression of tumors in pre-clinical animal models via production of high amounts of IFN-gamma and the death receptor ligand TRAIL. Thus, Imatinib exerts potent immuno-modulatory effects in vitro and in vivo, which will be discussed together with their clinical relevance in detail throughout this review.
 ...
PMID:The kinase inhibitor imatinib--an immunosuppressive drug? 1750 22

Mutant forms of the c-ABL gene are well known to be involved in hematopoietic malignancies such as chronic myeloid leukemia (CML). CML patients possess a fused BCR-ABL gene that activates the Abl tyrosine kinase domain within Bcr-Abl. In general fusion proteins that cause oligomerization of Abl lead to activation of its tyrosine kinase activity. In this review, we highlight recent discoveries indicating that the activated c-Abl tyrosine kinase, not as a fusion protein, plays an important role in malignant solid tumors of lung and breast.
 ...
PMID:Activated c-Abl tyrosine kinase in malignant solid tumors. 1839 83

Myeloproliferative disorders (MPD) are stem cell-derived clonal diseases arising as a consequence of acquired aberrations in c-ABL, Janus-activated kinase 2 (JAK2), and platelet-derived growth factor receptor (PDGFR) that generate oncogenic fusion tyrosine kinases (FTK), including BCR/ABL, TEL/ABL, TEL/JAK2, and TEL/PDGFbetaR. Here, we show that FTKs stimulate the formation of reactive oxygen species and DNA double-strand breaks (DSB) both in hematopoietic cell lines and in CD34(+) leukemic stem/progenitor cells from patients with chronic myelogenous leukemia (CML). Single-strand annealing (SSA) represents a relatively rare but very unfaithful DSB repair mechanism causing chromosomal aberrations. Using a specific reporter cassette integrated into genomic DNA, we found that BCR/ABL and other FTKs stimulated SSA activity. Imatinib-mediated inhibition of BCR/ABL abrogated this effect, implicating a kinase-dependent mechanism. Y253F, E255K, T315I, and H396P mutants of BCR/ABL that confer imatinib resistance also stimulated SSA. Increased expression of either nonmutated or mutated BCR/ABL kinase, as is typical of blast phase cells and very primitive chronic phase CML cells, was associated with higher SSA activity. BCR/ABL-mediated stimulation of SSA was accompanied by enhanced nuclear colocalization of RAD52 and ERCC1, which play a key role in the repair. Taken together, these findings suggest a role of FTKs in causing disease progression in MPDs by inducing chromosomal instability through the production of DSBs and stimulation of SSA repair.
 ...
PMID:BCR/ABL and other kinases from chronic myeloproliferative disorders stimulate single-strand annealing, an unfaithful DNA double-strand break repair. 1875

Imatinib, nilotinib and dasatinib are protein kinase inhibitors which target the tyrosine kinase activity of the Breakpoint Cluster Region-Abelson kinase (BCR-ABL) and are used to treat chronic myelogenous leukemia. Recently, using a chemical proteomics approach another tyrosine kinase, the collagen receptor Discoidin Domain Receptor1 (DDR1) has also been identified as a potential target of these compounds. To further investigate the interaction of imatinib, nilotinib and dasatinib with DDR1 kinase we cloned and expressed human DDR1 and developed biochemical and cellular functional assays to assess their activity against DDR1 and the related receptor tyrosine kinase Discoidin Domain Receptor2 (DDR2). Our studies demonstrate that all 3 compounds are potent inhibitors of the kinase activity of both DDR1 and DDR2. In order to investigate the question of selectivity among DDR1, DDR2 and other tyrosine kinases we have aligned DDR1 and DDR2 protein sequences to other closely related members of the receptor tyrosine kinase family such as Muscle Specific Kinase (MUSK), insulin receptor (INSR), Abelson kinase (c-ABL), and the stem cell factor receptor (c-KIT) and have built homology models for the DDR1 and DDR2 kinase domains. In spite of high similarity among these kinases we show that there are differences within the ATP-phosphate binding loop (P-loop), which could be exploited to obtain kinase selective compounds. Furthermore, the potent DDR1 and DDR2 inhibitory activity of imatinib, nilotinib and dasatinib may have therapeutic implications in a number of inflammatory, fibrotic and neoplastic diseases.
 ...
PMID:Inhibition of collagen-induced discoidin domain receptor 1 and 2 activation by imatinib, nilotinib and dasatinib. 1893 56

Here we demonstrated that the 'loss of function' of not-rearranged c-ABL in chronic myeloid leukemia (CML) is promoted by its cytoplasmic compartmentalization bound to 14-3-3 sigma scaffolding protein. In particular, constitutive tyrosine kinase (TK) activity of p210 BCR-ABL blocks c-Jun N-terminal kinase (JNK) phosphorylation leading to 14-3-3 sigma phosphorylation at a critical residue (Ser(186)) for c-ABL binding in response to DNA damage. Moreover, it is associated with 14-3-3 sigma over-expression arising from epigenetic mechanisms (promoter hyper-acetylation). Accordingly, p210 BCR-ABL TK inhibition by the TK inhibitor Imatinib mesylate (IM) evokes multiple events, including JNK phosphorylation at Thr(183), p38 mitogen-activated protein kinase (MAPK) phosphorylation at Thr(180), c-ABL de-phosphorylation at Ser residues involved in 14-3-3 binding and reduction of 14-3-3 sigma expression, that let c-ABL release from 14-3-3 sigma and nuclear import, and address BCR-ABL-expressing cells towards apoptotic death. Informational spectrum method (ISM), a virtual spectroscopy method for analysis of protein interactions based on their structure, and mathematical filtering in cross spectrum (CS) analysis identified 14-3-3 sigma/c-ABL binding sites. Further investigation on CS profiles of c-ABL- and p210 BCR-ABL-containing complexes revealed the mechanism likely involved 14-3-3 precluded phosphorylation in CML cells.
 ...
PMID:14-3-3 ligand prevents nuclear import of c-ABL protein in chronic myeloid leukemia. 1922 Aug 9

Imatinib (Glivec or Gleevec) potently inhibits the tyrosine kinase activity of BCR-ABL, a constitutively activated kinase, which causes chronic myelogenous leukemia (CML). Here we report the first almost complete backbone assignment of c-ABL kinase domain in complex with imatinib.
 ...
PMID:Backbone NMR resonance assignment of the Abelson kinase domain in complex with imatinib. 1963 20

Constitutive tyrosine kinase (TK) activity of p210 BCR-ABL fusion protein of chronic myeloid leukemia (CML) usurps physiological functions of normal p145 c-ABL protein. Accordingly, its inhibition by imatinib mesylate (IM) lets p145 c-ABL translocate into the nuclear compartment, which drives cell growth arrest and apoptotic death. Here we show that IM and the mammalian target of rapamycin (mTOR) inhibitor RAD001 (Everolimus) have additive effects on BCR-ABL-expressing cells. Those effects are at least partly conditional upon the enhanced nuclear accumulation of p145 c-ABL through events encompassing post-translational modifications of p145 c-ABL (Thr(735) phosphorylation) precluding its nuclear export and of 14-3-3 sigma (Ser(186) phosphorylation by c-Jun N-terminal kinase [JNK]) promoting p145 c-ABL nuclear re-import.
 ...
PMID:mTOR inhibitor RAD001 (Everolimus) enhances the effects of imatinib in chronic myeloid leukemia by raising the nuclear expression of c-ABL protein. 1964 77

Genes encoding c-ABL kinase and BCR protein are targeted by yet-unknown mechanisms causing DNA double-strand breaks resulting in the generation of a chimeric gene encoding BCR/ABL fusion tyrosine kinase. BCR/ABL kinase displays transforming activity because of its constitutive kinase activity causing deregulated proliferation, apoptosis, differentiation, and adhesion. Moreover, BCR/ABL kinase is able to facilitate DNA repair, prolong activation of G2/M and S cell cycle checkpoints, and elevate expression of the antiapoptotic protein Bcl-X(L), making malignant cells less responsive to antitumor treatment. BCR/ABL may also stimulate generation of reactive oxygen species and enhance spontaneous DNA damage in tumor cells. Unfortunately, BCR/ABL kinase compromises the fidelity of DNA repair mechanisms, thus contributing to the accumulation of additional genetic abnormalities that lead to resistance to inhibitors such as imatinib mesylate and to malignant progression of the disease. Therefore, chronic myelogenous leukemia cells display mutator phenotype.
 ...
PMID:Genomic instability: The cause and effect of BCR/ABL tyrosine kinase. 2042 53


<< Previous 1 2 3 4 5 Next >>