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)

The low potential cytochrome b (b-245) of the microbicidal oxidase of phagocytic cells has been purified from neutrophils from patients with chronic myeloid leukaemia. Cells were homogenized in the presence of proteinase inhibitors and centrifuged to remove the cytoplasm. The pellets containing membranes, granules and other organelles (15 mg/ml) were then washed with buffered sodium cholate (5 mg/ml). Residual pellets were subsequently solubilized with the non-ionic detergent Triton N 101 (10 mg/ml) which extracted about 60% of the cytochrome b. About 10% of the cytochrome b was of mitochondrial origin which was removed on a column of n-amino-octyl-Sepharose that did not adsorb cytochrome b-245. Cytochrome b-245 was chromatographed on a column of heparin-agarose and eluted with NaCl to give a peak specific content of 11-16 nmol of cytochrome b-245/mg of protein, representing a 140-200-fold purification with a recovery of 15%. This technique results in the purification of approx. 100-150 nmol of highly purified cytochrome b-245 from (3-5) X 10(11) cells within 4 days. The most purified material gave a broad band with an apparent Mr of between 68 000 and 78 000 on sodium dodecyl sulphate/polyacrylamide gel electrophoresis, but gel filtration indicated an aggregated form of the protein in Triton N101 . Purified protein (14 nmol of haem/mg of protein) did not contain FAD or FMN and had no NADPH-dependent O2--generating activity.
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PMID:Purification of cytochrome b-245 from human neutrophils. 633 90

The hybrid gene BCR-ABL that typifies chronic myeloid leukemia (CML) represents an attractive target for therapy with antisense oligodeoxyribonucleotides (ODN). A central obstacle in the therapeutic application of ODN is their poor cellular uptake. Adding various lipophilic conjugates to the ODN backbone has been reported to improve uptake, and electroporation of target cells has also been shown to enhance intracellular ODN delivery. We have shown that (1) BCR-ABL-directed ODN will specifically decrease the level of BCR-ABL mRNA, provided that cells are first permeabilized with Streptolysin-O (SL-O), and (2) chimeric methylphosphonodiester:phosphodiester ODN directed against 9 bases either side of the BCR-ABL junction are more efficient ODN effectors than structures composed solely of phosphodiester or phosphorothioate linkages. In this study, we compared the efficacy of lipophilic conjugation, SL-O permeabilization and electroporation on the intracellular delivery and molecular effect of BCR-ABL-directed ODN. b2a2- and b3a2-directed chimeric ODN were synthesized either unmodified or with one of the following groups at the 5' end: cholesterol, vitamin E, polyethylene glycol of average molecular weight 2,000 or 5,000, N-octyl-oligo-oxyethylene, or dodecanol. ODN associated with Lipofectin was also studied. Comparison was made in untreated, electroporated, and SL-O permeabilized KYO1 cells. Uptake was examined by fluorescence microscopy and flow cytometry, using ODN structures that were 3' labeled with fluorescein. The effect on target BCR-ABL mRNA expression was analyzed by Northern blotting. Several conjugated structures associated avidly with the cell membrane without achieving significant intracellular uptake or molecular effect. Similarly, ODN:Lipofectin complexes moderately increased cell association, without enhancing intracellular levels of ODN or inducing detectable molecular effect. In SL-O permeabilized or electroporated cells, uptake was approximately 1 to 2 logs greater than in untreated cells, and rapid nuclear localization was seen, especially with unmodified chimeric ODN. In SL-O permeabilized cells treated with ODN directed to the b2a2 and b3a2 junctions respectively, b2a2 BCR-ABL mRNA levels at 4 hours were reduced to 2. 6% +/- 2.1% and 38.4% +/- 1.3% of control values. In cells permeabilized by electroporation, BCR-ABL mRNA levels were decreased to 4.0% +/- 1.4% of control levels by b2a2 directed ODN, although very little nontargeted suppression was seen with b3a2-targeted ODN (93.4% +/- 4.2% of control). Greater cell to cell variation in ODN uptake was seen for SL-O permeabilized cells when compared with electroporated cells, suggesting that, after SL-O permeabilization, relatively unpermeabilized and overpermeabilized populations may coexist. No structure had any effect on the level of irrelevant (p53, MYC, and GADPH) mRNA levels. We conclude that the conjugation of chimeric ODN with one of the above-mentioned lipophilic groups or the complexing of ODN with Liopfectin does not improve either intracellular delivery of ODN or the molecular effect. In contrast, both electroporation and SL-O permeabilization (1) considerably enhanced uptake of chimeric ODN (even for structures without a conjugate group) and (2) achieved significant suppression of target mRNA levels.
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PMID:Improving the intracellular delivery and molecular efficacy of antisense oligonucleotides in chronic myeloid leukemia cells: a comparison of streptolysin-O permeabilization, electroporation, and lipophilic conjugation. 961 72

Signal Transduction Inhibitor 571 (STI571, formerly known as CGP 57148B) or Gleevec received fast track approval by the US Food and Drug Administration (FDA) for treatment of chronic myeloid leukemia (CML). STI571 (Gleevec) is a revolutionary and promising new oral therapy for CML, which functions at the molecular level with high specificity. The dramatic improvement in efficacy compared with existing treatments prompted an equally profound increase in the pace of development of Gleevec. The duration from first dose in man to completion of the New Drug Application (NDA) filing was less than 3 years. In addition, recently, FDA approved Gleevec for the treatment of gastrointestinal stromal tumor (GIST). In order to support all toxicokinetic (TK) studies with sufficient speed to meet various target dates, a semi-automated procedure using solid phase extraction (SPE) was developed and validated. A Packard Multi-Probe I and a SPE step in a 96-well plate format were utilized. A 3M Empore octyl (C(8))-standard density 96-well plate was used for plasma sample extraction. A Sciex API 3000 triple quadrupole mass spectrometer with an atmospheric pressure chemical ionization (APCI) interface operated in positive ion mode was used for detection. Lower limits of quantification of 1.00 and 2.00 ng/ml were attained for STI571 and its metabolite, CGP 74588, respectively. The method proved to be rugged and allowed the simultaneous quantification of STI571 and CGP 74588 in monkey plasma. Herein, assay development, validation, and representative concentration-time profiles obtained from TK studies are presented.
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PMID:Quantification of the anti-leukemia drug STI571 (Gleevec) and its metabolite (CGP 74588) in monkey plasma using a semi-automated solid phase extraction procedure and liquid chromatography-tandem mass spectrometry. 1204 82

The K562 cell line has been proposed as a useful experimental system to identify anti-tumor compounds acting by inducing terminal erythroid differentiation. K562 cells exhibit a low proportion of hemoglobin-synthesizing cells under standard cell growth conditions, but are able to undergo terminal erythroid differentiation when treated with a variety of anti-tumor compounds. In this paper we report a screening study on a set of different modified C(5) uracil derivatives for the evaluation of their antiproliferative effect in connection with erythroid differentiation pathways, and for defining a new class of drug candidates for the treatment of chronic myelogenous leukemia. Activity of the derivatives tested can be classified in two effect: an antiproliferative effect linked to a high level of erythroid differentiation activity and an antiproliferative effect without activation of gamma globin genes The highest antiproliferative effect and erythroid induction was shown by compound 9, a thymine derivative bearing a n-octyl chain on nitrogen N(1), whereas thymine did not show any effect, suggesting the importance of the linear alkyl chain in position N(1). To our knowledge this compound should be considered among the most efficient inducers of erythroid differentiation of K562 cells. This work is the starting point for the quest of more effective and specific drugs for the induction of terminal erythroid differentiation, for leading new insights in the treatment of neoplastic diseases with molecules acting by inducing differentiation rather than by simply exerting cytotoxic effects.
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PMID:C(5) modified uracil derivatives showing antiproliferative and erythroid differentiation inducing activities on human chronic myelogenous leukemia K562 cells. 2195 70

Some amino acid derivatives, such as R-glycine, have been synthesized together with their full spectroscopic characterization. The sodium salts of these bidentate amino acid ligands have been interacted with [M(bpy)(H2O)2](NO3)2 giving the corresponding some new complexes with formula [M(bpy)(R-gly)]NO3 (where M is Pt(II) or Pd(II), bpy is 2,2'-bipyridine and R-gly is butyl-, hexyl- and octyl-glycine). Due to less solubility of octyl derivatives, the biological activities of butyl and hexyl derivatives have been tested against chronic myelogenous leukemia cell line, K562. The interaction of these complexes with highly polymerized calf thymus DNA has been extensively studied by means of electronic absorption, fluorescence and other measurements. The experimental results suggest that these complexes positive cooperatively bind to DNA presumably via groove binding. Molecular dynamic results show that the DNA structure is largely maintained its native structure in hexylglycine derivative-water mixtures and at lower temperatures. The simulation data indicates that the more destabilizing effect of butylglycine is induced by preferential accumulation of these molecules around the DNA and due to their more negative free energy of binding via groove binding.
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PMID:Rich spectroscopic and molecular dynamic studies on the interaction of cytotoxic Pt(II) and Pd(II) complexes of glycine derivatives with calf thymus DNA. 2573 64