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)

We designed a novel multiplex in-cell reverse transcription-polymerase chain reaction method for the simultaneous detection and differentiation of p190 and p210 BCR-ABL mRNAs within single cells from the human chronic myeloid leukemia and Philadelphia positive acute lymphoblastic leukemia. Human K562 chronic myeloid leukemia and SUP B-15 Ph+ acute lymphoblastic leukemia cell lines were used as positive controls for p210 and p190 BCR-ABL mRNAs, respectively. HL60 cell line was used as a negative control. After the leukemia cells were fixed and permeabilized, without extracting nucleic acids, the mRNAs were reverse transcribed to cDNAs, and the cDNAs were amplified by multiplex polymerase chain reaction with fluorescent primers specific for p190 and p210 BCR-ABL mRNAs. After transfer onto glass slides by cytospin, the amplified cells were detected by fluorescence microscopy. Fluorescence microscopy after propidium iodide or 4',6-diamidino-2-phenylindone counterstaining showed that the positive K562 cells exhibited a yellow-green fluorescent cytoplasm around a red nucleus, and that the positive SUP B-15 cells exhibited an orange cytoplasm around a blue nucleus. Only the red or blue nucleus was visible in respective negative HL60 cells. The specificity of amplification was confirmed by the absence of a signal when control experiments were performed either with RNase digestion of mRNA or without reverse transcriptase/Taq polymerase. We conclude that the multiplex in-cell reverse transcription-polymerase chain reaction method is capable of simultaneously detecting and differentiating the p210 and p190 BCR-ABL mRNAs of chronic myeloid leukemia and Philadelphia-positive acute lymphoblastic leukemia cells, and that it may be useful in quantitatively monitoring the minimal residual disease during therapy.
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PMID:Multiplex in-cell reverse transcription-polymerase chain reaction for the simultaneous detection of p210 and p190 BCR-ABL mRNAs in chronic myeloid leukemia and Philadelphia-positive acute lymphoblastic leukemia cell lines. 1109 54

Bcr-Abl, the product of the protooncogene bcr-abl, is a constitutively active protein-tyrosine kinase that is highly expressed in chronic myelogenous leukemia and in acute myeloid leukemia cells. Because Bcr-Abl is known to provide mitogenic signals through suppression of apoptosis, we investigated the effect of this oncogene product on signaling by tumor necrosis factor (TNF), a proapoptotic cytokine. We used a bcr-abl-deficient human megakaryocytic leukemia cell line MO7E and an isogenic MBA cell line stably transfected with bcr-abl. Electrophoretic mobility shift assay revealed that TNF activated the nuclear transcription factor NF-kappaB in MO7E cells but not in MBA cells. The impaired NF-kappaB activation in Bcr-Abl-expressing cells was not due to absence of the NF-kappaB proteins p65, p50, or p100 or of IkappaBalpha or IkappaBbeta. Okadaic acid-induced NF-kappaB activation was unaffected by Bcr-Abl expression. TNF induced IkappaBalpha phosphorylation and degradation in MO7E cells but not in MBA cells. The suppression of TNF-induced NF-kappaB activation by Bcr-Abl was not restricted to MBA cells, because ectopic expression of Bcr-Abl in human acute myeloid leukemia HL-60 cells also blocked TNF-induced NF-kappaB activation. When examined for the TNF receptors by the radioreceptor assay, flow cytometry, or Western blot analysis, we found that Bcr-Abl expression down-regulated the expression of the TNF receptors. The RNase protection assay and Northern blot analysis revealed the transcriptional down-regulation of the TNF receptor by Bcr-Abl protein. Overall, these results indicate that ectopic expression of Bcr-Abl interferes with the TNF signaling pathway through the down-regulation of TNF receptors.
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PMID:Ectopic expression of protein-tyrosine kinase Bcr-Abl suppresses tumor necrosis factor (TNF)-induced NF-kappa B activation and IkappaBalpha phosphorylation. Relationship with down-regulation of TNF receptors. 1206 Jun 65

Proteomic analysis using electrospray liquid chromatography-mass spectrometry (ESI-LC-MS) has been used to compare the sites of glycation (Amadori adduct formation) and carboxymethylation of RNase and to assess the role of the Amadori adduct in the formation of the advanced glycation end-product (AGE), N(epsilon)-(carboxymethyl)lysine (CML). RNase (13.7 mg/mL, 1 mM) was incubated with glucose (0.4 M) at 37 degrees C for 14 days in phosphate buffer (0.2 M, pH 7.4) under air. On the basis of ESI-LC-MS of tryptic peptides, the major sites of glycation of RNase were, in order, K41, K7, K1, and K37. Three of these, in order, K41, K7, and K37 were also the major sites of CML formation. In other experiments, RNase was incubated under anaerobic conditions (1 mM DTPA, N2 purged) to form Amadori-modified protein, which was then incubated under aerobic conditions to allow AGE formation. Again, the major sites of glycation were, in order, K41, K7, K1, and K37 and the major sites of carboxymethylation were K41, K7, and K37. RNase was also incubated with 1-5 mM glyoxal, substantially more than is formed by autoxidation of glucose under experimental conditions, but there was only trace modification of lysine residues, primarily at K41. We conclude the following: (1) that the primary route to formation of CML is by autoxidation of Amadori adducts on protein, rather than by glyoxal generated on autoxidation of glucose; and (2) that carboxymethylation, like glycation, is a site-specific modification of protein affected by neighboring amino acids and bound ligands, such as phosphate or phosphorylated compounds. Even when the overall extent of protein modification is low, localization of a high proportion of the modifications at a few reactive sites might have important implications for understanding losses in protein functionality in aging and diabetes and also for the design of AGE inhibitors.
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PMID:Proteomic analysis of the site specificity of glycation and carboxymethylation of ribonuclease. 1458 47

Microbial RNases along with such animal RNases as onconase and BS-RNase are a promising basis for developing new antitumor drugs. We have shown that the Bacillus intermedius RNase (binase) induces selective apoptosis of transformed myeloid cells. It attacks artificially expressing activated c-Kit myeloid progenitor FDC cells and chronic myelogenous leukemia cells K562. Binase did not induce apoptosis in leukocytes of healthy donors and in normal myeloid progenitor cells. The inability of binase to initiate expression of activation markers CD69 and IFN-gamma in CD4+ and CD8+ T-lymphocytes testifies that enzyme is devoid of superantigenic properties. Altogether, these results demonstrate that binase possesses therapeutic opportunities for treatment of genotyped human neoplasms expressing activated kit.
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PMID:Binase induces apoptosis of transformed myeloid cells and does not induce T-cell immune response. 1768 90

Methylglyoxal (MG) is generated through the Embden-Meyerhof and polyol pathways, and it rapidly reacts with proteins to form advanced glycation end products (AGE) such as N(epsilon)-(carboxyethyl)lysine (CEL). In the present study, polyclonal and monoclonal antibodies specific for CEL were prepared to estimate CEL content in aldehydes-modified proteins and the pathological localization in human kidneys. Polyclonal CEL-specific antibody was prepared by removing cross-reactive antibodies against N(epsilon)-(carboxymethyl) lysine (CML), one of the major AGE structures, using CML-conjugated affinity chromatography. Monoclonal CEL-specific antibody (CEL-SP) was obtained by immunization with CEL-bovine serum albumin, followed by successive screening according to CEL-RNase-positive but CML-RNase-negative criteria. A non-competitive ELISA showed that both the polyclonal and monoclonal CEL-specific antibodies significantly reacted with CEL-proteins but not with CML-proteins. A competitive ELISA also demonstrated that CEL-SP does not show cross-reactivity against CEL analogues such as CML, carboxymethylarginine (CMA) and S-carboxymethylcysteine (CMC), thus indicating that antibody is able to recognize the difference of one methyl group between carboxymethyl group and carboxyethyl group. Furthermore, CEL-SP significantly reacted with human serum albumin modified with MG but not with glyoxal or 3-deoxyglucosone, and its reactivity was highly correlated with the CEL content, which was determined by high performance liquid chromatography. Immunohistochemical studies using CEL-SP provided evidence that CEL-modified proteins accumulate in distal tubular epithelial cells of the diabetic rat. These results demonstrate that a specific antibody against CEL can be a powerful tool for detecting CEL both in vitro and in vivo.
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PMID:Immunochemical detection of Nepsilon-(carboxyethyl)lysine using a specific antibody. 1824 32

The aim of this study was to investigate the effects of 2-methoxyestradiol (2-ME) on expressions of caspase-3 and survivin in chronic myelocytic leukemia (CML) K562 cells. The experiment was divided into 3 groups: control group, in which K562 cells were cultured in medium without 2-ME; the experimental group, in which K562 cells were cultured in medium containing different concentrations of 2-ME (1, 2, 4, 8 and 16 micromol/L) for 36 hours; the negative control group, in which K562 cells were replaced by distilled water without RNase in medium. The apoptosis rate, the protein and its mRNA expressions of caspase-3 and survivin of K562 cells was detected by TUNEL, flow cytometry (FCM), half-quantitative RT-PCR respectively. The results showed that the apoptosis rate of K562 cells in experimental group was significantly higher than that in control group (p < 0.05). The apoptosis rate of K562 cells detected by FCM was almost the same as that detected by TUNEL method (p < 0.01). The result detected by TUNEL methods was positively correlated with that detected by FCM (gamma = 0.845, p = 0.034). The expression of caspase-3 protein increased in a concentration-dependent manner, and also this expression level in the experimental group was higher than that in the control group (p < 0.05); the expression of survivin protein decreased along with the increasing of 2-ME concentration. and the difference between the experimental group and the control group was statistically significant (p < 0.05). The expression of caspase-3 mRNA was higher in the experimental group than that in the control group (p < 0.01), and the expression of survivin mRNA was lower in the experimental group than that in the control group (p < 0.01). The expression level of caspase-3 mRNA was negatively correlated with that of survivin (gamma = -0.966, p = 0.001). It is concluded that the 2-ME can induce apoptosis of K562 cells in a concentration-dependent manner and indicate its promising potential in the treatment of CML patients.
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PMID:[Effects of 2-methoxyestradiol on the expression of caspase-3 and survivin in chronic myelocytic leukemia K562 cells]. 1937 62

This review summarizes data on ambiguous biological functions of ribonucleases (RNases) at tumor growth. In some cases the raised level of enzyme activity in biological fluids can be regarded as an additional marker of malignant growth (pancreas cancer, chronic myeloid leukemia, etc.). At the same time the activity of RNases is often lowered in tumor tissue. High substrate specificity of particular RNases provides metabolic balance between various kinds of RNAs with various half-time exchange turn. RNases are the important factors of epigenetic regulation of gene activity in cells. The activity of RNases is adjustable by inhibitors and other factors, and defines time of existence of different kinds of RNAs. RNases (the modified variants of RNase A, RNases of semen fluid of the cattle, RNase of amphibia oocytes) can be used as anti-tumor therapeutic agents. On the other hand, some inhibitors of RNases of natural or synthetic origin were demonstrated to be perspective drugs that inhibit tumor growth.
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PMID:Ribonucleases in tumor growth. 1978 70

The endoribonuclease RNase-L is the terminal component of an interferon-regulated RNA decay pathway known as the 2'-5'-oligoadenylate (2-5A) system, whose established functions include antimicrobial and tumor suppressive activities. RNase-L activity requires binding of the small molecule 2-5A, leading to RNase-L dimerization and cleavage of single-stranded RNA. RNase-L expression is controlled post-transcriptionally by its 3'-untranslated region (3' UTR), which exerts a strong negative effect on RNase-L levels. MicroRNAs (miRNAs) are a class of small noncoding RNAs that repress expression of target genes by binding to regions of complementarity often in the 3' UTR. The miR-29 family acts as a tumor suppressor in several cancers, including acute and chronic myelogenous leukemia (CML), and has many oncogenic targets. We report that the miR-29 family represses RNase-L protein expression across several cell types. Using a luciferase reporter, we showed that miR-29 acts via 4 target sites within the RNASEL 3' UTR. Mutation of all sites is required for abrogation of miR-29 repression. In light of the reported tumor suppressive role of miR-29 in K562 CML cells and miR-29 repression of RNase-L in these cells, we generated K562 cells with stable RNase-L knockdown and demonstrated that loss of RNase-L inhibits proliferation in vitro as well as tumor growth in a xenograft model. Our findings identify a previously unknown miRNA regulator of RNase-L expression and support a novel oncogenic role for RNase-L in CML and potentially other hematopoietic malignancies.
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PMID:Regulation of human RNase-L by the miR-29 family reveals a novel oncogenic role in chronic myelogenous leukemia. 2311 44


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