Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts: Gene/Protein Disease Symptom Drug Enzyme Compound   Target Concepts: Gene/Protein Disease Symptom Drug Enzyme Compound

---

Query: EC:2.7.10.2 (focal adhesion kinase)
44,029 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Chronic myeloid leukemia (CML) is typified by robust marrow and extramedullary myeloid cell production. In the absence of therapy or sometimes despite it, CML has a propensity to progress from a relatively well tolerated chronic phase to an almost uniformly fatal blast crisis phase. The discovery of the Philadelphia chromosome followed by identification of its BCR-ABL fusion gene product and the resultant constitutively active P210 BCR-ABL tyrosine kinase, prompted the unraveling of the molecular pathogenesis of CML. Ground-breaking research demonstrating that BCR-ABL was necessary and sufficient to initiate chronic phase CML provided the rationale for targeted therapy. However, regardless of greatly reduced mortality rates with BCR-ABL targeted therapy, most patients harbor quiescent CML stem cells that may be a reservoir for disease progression to blast crisis. While the hematopoietic stem cell (HSC) origin of CML was first suggested over 30 years ago, only recently have the HSC and progenitor cell-specific effects of the molecular mutations that drive CML been investigated. This has provided the impetus for investigating the genetic and epigenetic events governing HSC and progenitor cell resistance to therapy and their role in disease progression. Accumulating evidence suggests that the acquired BCR-ABL mutation initiates chronic phase CML and results in aberrant stem cell differentiation and survival. This eventually leads to the production of an expanded progenitor population that aberrantly acquires self-renewal capacity resulting in leukemia stem cell (LSC) generation and blast crisis transformation. Therapeutic recalcitrance of blast crisis CML provides the rationale for targeting the molecular pathways that drive aberrant progenitor differentiation, survival and self-renewal earlier in disease before LSC predominate.
...
PMID:Chronic myeloid leukemia stem cells. 1907 22

Chronic myeloid leukemia (CML) is characterized by the presence of the Philadelphia (Ph) chromosome, which results from a reciprocal translocation between the long arms of the chromosomes 9 and 22 t(9;22)(q34;q11). This translocation creates two new genes, BCR-ABL on the 22q- (Ph chromosome) and the reciprocal ABL-BCR on 9q-. The BCR-ABL gene encodes for a 210-kD protein with deregulated tyrosine kinase (TK) activity, which is crucial for malignant transformation in CML. The recognition of the BCR-ABL gene and corresponding protein led to the synthesis of small-molecule drugs, designed to interfere with BCR-ABL tyrosine kinase activation by competitive binding at the ATP-binding site. The first tyrosine kinase inhibitor (TKI), introduced into clinical practice in 1998, was imatinib mesylate. Imatinib became the first choice drug in chronic phase CML, because of its high efficacy, low toxicity and ability to maintain durable hematological and cytogenetic responses. However, approximately 20-25% of patients initially treated with imatinib will need alternative therapy, due to drug resistance, which is often caused by the appearance of clones expressing mutant forms of BCR-ABL. Second-generation TKIs have provided new therapeutic option for the patients resistant to imatinib. Dasatinib is the first, second-generation TKI, approved in the US and European Union for the treatment of CML patients with imatinib resistance or intolerance. This drug is a dual SRC-ABL kinase inhibitor, active in most clinically relevant BCR-ABL mutations, except highly resistant T315I. Other second-generation TKIs include nilotinib, bosutinib and INNO 406. Apart from TKIs, the promising group of molecules is inhibitors of Aurora family of serine-threonine kinases. One of these molecules, MK0457, has entered clinical trials, and initial reports indicate that this compound could be active in disease associated with T315I mutation. Thus, wide spectrum of new agents, with different mode of action, is currently in clinical development for CML. It is likely that combination therapy will be the best therapeutic strategy in the future.
...
PMID:Targeted drugs in chronic myeloid leukemia. 1907 51

Although imatinib mesylate therapy is effective for chronic myeloid leukemia (CML) patients, there are still some unanswered questions. It is unclear whether imatinib can actually cure CML and whether this therapy can be safely discontinued in patients showing complete cytogenetic and molecular responses. This report describes the clinical outcome of a patient with chronic phase CML who discontinued imatinib therapy after achieving molecular remission. This patient has shown a relapse based on transcription-mediated amplification-hybridization protection assay (TMA-HPA) to monitor BCR-ABL transcripts, highlighting the uncertainty of discontinuing imatinib therapy for five months.
...
PMID:[Molecular relapse of chronic myeloid leukemia after discontinuation of imatinib mesylate for maintaining complete molecular response for more than 2 years]. 1922 31

We report a clinical case of chronic myelogenous leukaemia (CML) with regional B-lymphoblastic transformation. Peripheral leukocytosis of 160 x 10(9)/L, splenomegaly and fatigue suggested CML. In peripheral blood and bone marrow smears, white blood cells in all maturation stages and only few blasts were seen and therefore the diagnosis of chronic phase CML was proposed. Cytogenetics performed on peripheral blood cells revealed the characteristic t(9;22)(q34;q11) translocation as solitary abnormality. Analyzing the bone marrow biopsy a focal nodular B-lymphoid blast component was additionally seen. BCR-ABL FISH analysis demonstrated 31% atypical split signals in the B-lymphoid blasts and in the maturing myeloid cells, furthermore, BCR-ABL fusion transcripts were seen in the RT-PCR assay. Imatinib-based therapy led to temporary regression of peripheral leukocytosis. Bone marrow examination 3 weeks after therapy induction demonstrated considerably reduced cellularity and the proportion of B-lymphoid blasts had decreased to 20% of the nuclear cells. BCR-ABL FISH analysis still presented 21% atypical split signals but levels of BCR-ABL transcripts had significantly fallen indicating a rather favourable prognosis. However, 3 months after diagnosis the patient relapsed and developed an immunodeficiency with soor esophagitis and aspergillus pneumonia. A therapy with dasatinib was not successful and the patient died in consequence of immunodeficiency. This report demonstrates the high diagnostic value of bone marrow biopsy in the evaluation of CML. Besides morphology investigation of diverse methods including RT-PCR and FISH performed on diagnostic bone marrow biopsies are obligatory for ideal monitoring of drug response.
...
PMID:High diagnostic value of morphologic examination and molecular analysis of bone marrow biopsies in a case of BCR-ABL+ CML with clusters of blasts. 1922 89

Chronic myeloid leukemia (CML) is an acquired neoplastic hematopoietic stem cell (HSC) disorder characterized by the expression of the BCR-ABL oncoprotein. This gene product is necessary and sufficient to explain the chronic phase of CML. The only known cause of CML is radiation exposure leading to a mutation of at least one HSC, although the vast majority of patients with CML do not have a history of radiation exposure. Nonetheless, in humans, significant radiation exposure (after exposure to atomic bomb fallout) leads to disease diagnosis in 3-5 years. In murine models, disease dynamics are much faster and CML is fatal over the span of a few months. Our objective is to develop a model that accounts for CML across all mammals. In the following, we combine a model of CML dynamics in humans with allometric scaling of hematopoiesis across mammals to illustrate the natural history of chronic phase CML in various mammals. We show how a single cell can lead to a fatal illness in mice and humans but a higher burden of CML stem cells is necessary to induce disease in larger mammals such as elephants. The different dynamics of the disease is rationalized in terms of mammalian mass. Our work illustrates the relevance of animal models to understand human disease and highlights the importance of considering the re-scaling of the dynamics that accrues to the same biological process when planning experiments involving different species.
...
PMID:The allometry of chronic myeloid leukemia. 1936 66

The BCR-ABL inhibitor imatinib is standard first-line therapy for patients with chronic myeloid leukemia (CML) and has revolutionized treatment of the disease. However, resistance and intolerance to the agent have emerged as major clinical complications. Dasatinib is the first and only dual BCR-ABL/SRC family kinase inhibitor approved by the U.S. Food and Drug Administration for the treatment of patients with CML in any phase or Philadelphia chromosome-positive acute lymphoblastic leukemia who are resistant to or intolerant of imatinib. The agent is well tolerated and has shown clinical activity in such patients. As with other oral tyrosine kinase inhibitors, nonadherence to the prescribed dasatinib treatment regimen could obstruct a successful outcome. A new recommended dose of 100 mg once daily has been approved for patients with chronic phase CML. That dosing regimen, combined with appropriate management of dasatinib-related adverse events, may help patients adhere to their prescribed treatment and achieve maximum therapeutic benefit. This article highlights recent changes to the dasatinib label, including results with the 100 mg once-daily starting dose for patients with chronic phase CML, and discusses nursing strategies for the successful management of adverse events in patients receiving dasatinib.
...
PMID:A once-daily dasatinib dosing strategy for chronic myeloid leukemia. 1950 90

Deregulated BCR-ABL tyrosine kinase (TK) activity is the molecular marker for chronic myeloid leukemia (CML), which provides an identifiable target for developing therapeutic agents. Imatinib mesylate, a BCR-ABL TK inhibitor, is the frontline therapy for CML. Despite the stunning efficacy of this agent, a small number of patients develop a suboptimal response or resistance to imatinib. In newly diagnosed patients with chronic phase CML, the rate of resistance to imatinib at 4 years was up to 20%, increasing to 70% to 90% for patients in the accelerated/blastic phase. Resistance to imatinib led to the development of novel TK inhibitors such as dasatinib. Several clinical trials have reported more durable complete hematologic and cytogenetic responses with this agent in patients who are resistant or intolerant to imatinib. Dasatinib is well tolerated and has broad efficacy, resulting in durable responses in patients with any BCR-ABL mutation except for T3151 and mutations in codon 317 - most commonly F317L - including mutations that were highly resistant to imatinib, such as L248, Y253, E255, F359, and H396. Dasatinib is recommended for CML in chronic, blastic or accelerated phase that is resistant or intolerant to imatinib. Dasatinib was approved by the FDA at 100 mg once daily as the starting dose in patients with chronic phase CML and at 70 mg twice daily in patients with accelerated or blastic phase CML. Various clinical trial results provided evidence that resistance to one TK inhibitor can be reversed with the use of a different TK inhibitor (TKI). Other second-generation TKIs with activity in CML include nilotinib, bosutinib and INNO 406. New molecules, such as the inhibitor of Aurora family serine-threonine kinases, MK0457, which has antileukemic activity in CML associated with a T315I mutation, are being investigated. Allogeneic hematopoietic stem cell transplantation remains an option for selected patients.
...
PMID:Dasatinib in chronic myeloid leukemia: a review. 1953 17

Chronic myelogenous leukemia (CML) is a myeloproliferative disorder characterized by unregulated growth of myeloid leukemia cells in the bone marrow and accumulation of these cells in the blood. CML represents approximately 15-20% of all adult leukemia and the disease development is clearly linked to the constitutively active tyrosine kinase of the chimeric protein BCR-ABL. It is encoded by the Bcr-Abl fusion gene sequence as the result of chromosome 9/22 translocation (Philadelphia chromosome) or other aberrant cytogenetic events. The development of targeted agents that specifically inhibit the tyrosine kinase (TK) activity of BCR-ABL has revolutionized the treatment of CML. Imatinib is now the first-line treatment for chronic phase CML, and several newer tyrosine kinase inhibitors (TKIs) such as dasatinib and nilotinib have been added to the pharmacologic compendium. Despite the proven efficacy of TKIs to induce hematological and cytogenetic remission, the large majority of patients still have molecularly detectable disease. Therefore, new options are needed to improve therapeutic success in the treatment of leukemia. Pyrrolo[1,2-b][1,2,5]benzothiadiazepine 5,5-dioxides (PBTDs) induced apoptosis in human BCR-ABL expressing leukemia cells. The apoptotic activity was also observed in primary leukemic blasts, obtained from CML patients at onset or from patients in blast crisis and who were imatinib- dasatinib- and nilotinib resistant. These results suggests that these compounds are promising agent for the treatment of leukemia. Due to the fact that the phenomenon of resistance to TKIs remains a major issue in the treatment of patients with CML, the identification of new drugs may be of clinical relevance. This review summarises patents and papers dealing with the present understanding of mechanism of action and the most relevant data concerning TKs inhibition.
...
PMID:In vitro anti-leukaemia activity of pyrrolo[1,2-b][1,2,5]benzothiadiazepines (PBTDs). 1966 71

Chronic myeloid leukemia patients with different BCR-ABL transcripts might respond differently to Imatinib mesylate. This prompted us to study BCR-ABL transcripts in chronic myeloid leukemia (CML) patients and their correlation with response to Imatinib. Eighty-seven chronic phase CML patients (median age, 35 years; range, 13-62 years; M/F, 59:28) were included in this study; 57 patients had received interferon-alpha and/or hydroxyurea, and 30 were previously untreated. All patients received Imatinib mesylate (Gleevec) 400 mg daily. Complete hematological remission rate and major cytogenetic response (CGR) rates were 99% and 72%, respectively. B3a2 transcript was present in 53% of patients, b2a2 in 39%, and both transcripts in 8% of patients. Twenty of 34(59%) patients with b2a2 type achieved complete CGR compared to 15 of 53 (28%) patients with b3a2, p = 0.04. Among 24 patients with minor or no CGR, six (25%) had b2a2 compared to 18 (75%) b3a2 type, p = 0.04. Expression of BCR-ABL/ABL% was higher in b3a2 patients compared to b2a2, p = 0.120. Pre-treatment characteristics-mean spleen size (6.6 vs. 6.4 cm, p = 0.868), mean hemoglobin (G/dl; 12.0 vs. 11.8, p = 0.690), mean WBC count (83 x 10(9) vs. 77 x 10(9)/L, p = 0.923), and mean platelets counts (360x10(9) vs. 340 x 10(9)/L, p = 0.712)-were not significantly different in the b3a2 vs. b2a2 transcripts groups. Our preliminary findings suggest that CML patients with b2a2 BCR-ABL transcript might have higher CGRs to Imatinib mesylate (Gleevec).
...
PMID:Response to Imatinib mesylate in chronic myeloid leukemia patients with variant BCR-ABL fusion transcripts. 1971 31

Chronic myelogenous leukemia (CML) is associated with the Ph1 chromosome translocation, which produces a chimeric tyrosine-specific kinase gene, the product of the fusion of the BCR gene and the ABL gene. The immune system has long been implicated in the control of CML. We found oligoclonal T cell responses in treated patients with IFN-alpha or leukemic dendritic cells. Also other groups treated chronic phase CML (CP-CML) patients with various leukemic antigen peptides, resulted in apparent immune response and clinical response. Imatinib mesylate is currently used as the first line therapy for CP-CML patients. Although it selectively targets the ABL portion of BCR-ABL protein as a reversible tyrosine kinase inhibitor, it cannot kill the leukemic stem cells of CML. To find a possibility to enhance the immunity in imatinib-treated CML patients by combining it with immunotherapy, we summarized the immune response of innate and adaptive immunity in CML. Development of such immunotherapeutic strategies would be a promising approach to treat the imatinib-treated CML-CP patients.
...
PMID:[Immunological evaluation for CML and its possibility for an immunotherapy]. 1972 43


<< Previous 1 2 3 4 5 6 7 8 9 10 Next >>

---