Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UMLS:C0023418 (leukemia)
 93,477 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The first high performance liquid chromatographic method for determination of the plasma concentration of 2-chloro-2'-deoxyadenosine (CdA) in patients, which is significantly more sensitive than the previously used RIA method, is presented. CdA is a purine analogue with useful clinical activity against lymphoproliferative disorders and it has recently been found to be the single most active agent in the treatment of hairy cell leukaemia. Guaneran (6-nitroimidazol-6-thioguanine) was added to 1 mL plasma as the internal standard and CdA was extracted using ethyl acetate. A Perkin-Elmer C18, 3 mu, 8 cm column was used for the separation of CdA and the internal standard from endogenous compounds in the sample with a mixture of sodium phosphate buffer 10 mM, methanol and acetonitrile (85:10:5, pH = 3.0) as the mobile phase. The sensitivity of the method (1 nM) allows the determination of CdA in plasma 24 h after the administration of 0.14 mg/kg as a 2 h infusion.
 ...
PMID:Determination of 2-chloro-2'-deoxyadenosine in human plasma. 168 27

A method is described herein for the isolation and quantitation of polyglutamates of the thymidylate synthase (TS) inhibitor N10-propargyl-5,8-dideazafolic acid (CB3717) in tumor cells exposed to the drug in vitro. Cells were incubated with 50 microM 3H-CB3717 for 12 h and then disrupted by sonication. CB3717 and its polyglutamates were extracted by boiling in 0.01 M Tris-HCl pH 10. The extract was concentrated by lyophilization and analyzed by reverse phase HPLC (10 x 0.46-cm Polygosil 5-micron C18 column) using linear gradient elution (5-16% acetonitrile in 0.1 M sodium acetate, pH 5, over 15 min, 2 ml/min). Recovery of radioactivity at each stage of the method was greater than 70%. CB3717 and its polyglutamates were identified by co-chromatography with synthetic standards and by inhibition of partially purified TS. Quantitation was by means of radiochemical analysis. The 3H-CB3717 used in these studies was prepared by catalytic tritiation of diethyl-(2-chloro-4-nitrobenzoyl)-L-glutamate followed by consecutive alkylation with propargyl bromide and 2-amino-6-bromomethyl-3,4-dihydro-4-oxoquinazoline hydrobromide. The free diacid was prepared as required by hydrolysis in sodium hydroxide and purified by HPLC. Tritiation in only one position was confirmed by 3H NMR. Following the exposure of L1210 leukemia cells to 50 microM 3H-CB3717 for 12 h the total cellular radioactivity level was approximately 7 microM, of which 27% was present as polyglutamated metabolites with four and five glutamate residues.
 ...
PMID:Development of an assay for the estimation of N10-propargyl-5,8-dideazafolic acid polyglutamates in tumor cells. 246 Nov 14

In this study we detected a factor that stimulates the proliferation of bone marrow-derived hematopoietic precursors in diffusion chambers implanted in mice. This factor, called diffusible colony-stimulating factor (D-CSF), was found in medium conditioned in the presence of spleen and peripheral blood cells from mice with B cell leukemia (BCL1). After the administration of D-CSF, the number of colonies formed in the plasma clot inside the chamber (CFU-DG) was increased, as were the number of hematopoietic precursors (CFU-MIX, CFU-S, CFU-C, and BFU-E) as judged by a subculture of diffusion chamber contents. Depletion of macrophages and T cells from the spleen cell suspension did not decrease the production of D-CSF, thereby indicating that it was derived from B cells. Neoplastic BCL1 cells appear to be the source because D-CSF could not be detected in medium conditioned with normal B cells. BCL1-conditioned medium (CM) did not enhance CFU-MIX, BFU-E, and CFU-C colony formation in vitro, which suggested that D-CSF is different from multi-CSF, EPA, or CSF. The addition of BCL1 CM to multi-CSF-, erythroid potentiating activity (EPA), and CSF (EL-4CM)-containing cultures had no effect on CFU-MIX, BFU-E, and CFU-C colony formation, thus indicating the absence of a synergistic or inhibitory activity. On the other hand, EL-4 CM, which stimulates CFU-MIX, BFU-E, and CFU-C in vitro, had no effect on CFU-DG in vivo. Biochemical characterization of BCL1 CM revealed that D-CSF is relatively heat stable and loses its bioactivity with protease treatments. It binds to lentil-lectin, according to gel-filtration chromatography has a relative molecular weight of approximately 43,000, and on reverse-phase high-performance liquid chromatography elutes with acetonitrile. These data also indicate that transformed B cells may serve as a source for hematopoietic regulators that act on hematopoietic precursors in vivo.
 ...
PMID:Hematopoetic precursors respond to a unique B lymphocyte-derived factor in vivo. 282 36

The potential for differentiation of the human basophilic leukaemia cell line KU812 was examined by means of a panel of physiologic and non-physiologic substances used as inducers. The phenotypic characteristics of non-induced KU812 cells included an immature morphology with scanty cytoplasmic granulation, expression of a low amount of high affinity, but no low affinity receptors (CD 23) for IgE, and a capacity for low-rate histamine synthesis. The differentiation process was characterized by a rapid (24 h) increase in histamine production a slower morphological maturation with the development of Alcian blue stainable granula demonstrable after 72 h. Concomitant with the phenotypic alterations, cell growth was inhibited. Differentiation in KU812 cells was inducible by Ara-C and to some extent by sodium butyrate, but not by dimethyl sulphoxide, retinoic acid, or gamma-interferon. Conditioned medium (CM) from cultured peripheral blood cells from atopic individuals and 18 out of 22 analysed glioma cell lines induced differentiation of the KU812 cells, whereas supernatant from only 1 out of 21 other cell lines, including carcinoma, melanoma, sarcoma, leukaemia, and normal fibroblasts had this activity. CM from the T-leukaemic cell line, Mo, also induced KU812 differentiation. A primary fractionation of the active substance from this cell line by reversed phase chromatography eluted the active substance at a concentration of 42-44% acetonitrile. Our present study has shown that the KU812 may serve as an appropriate model to study differentiation of basophils. In addition, its fast and specific response to biological factors makes it suitable as a biological assay for determination of active factor produced by atopic individuals.
 ...
PMID:Induction of basophilic differentiation in the human basophilic cell line KU812. 297 55

An alpha-type transforming growth factor (TGF alpha) is produced at high levels by rat embryo cells transformed by the Snyder-Theilen strain of feline sarcoma virus (FeSV). Addition of 2 ng mouse epidermal growth factor (mEGF) during purification identified the presence of a second, EGF-dependent growth factor of the TGF beta type (TGF beta) in this conditioned medium. This factor had an approximate Mr of 12,000 and eluted at 37% acetonitrile during high performance liquid chromatography. This extracellular type of TGF beta activity also was present in conditioned medium of rat cells after infection with a transformation defective strain of Abelson leukemia virus, and hence expression of this growth factor activity was independent of cell transformation. Moreover, the presence of an EGF-dependent, 12,000 Mr clonogenic activity in extracts of bovine serum alone suggests serum as an origin for the B-type transforming growth factor initially observed in conditioned medium of Snyder-Theilen FeSV transformed cells. This does not, however, preclude the possibility that TGF beta is also secreted by the transformed rat embryo cells themselves.
 ...
PMID:A beta-type transforming growth factor, present in conditioned cell culture medium independent of cell transformation, may derive from serum. 298 78

The now classical major histocompatibility complex (MHC)-restricted receptor for antigen on human T lymphocytes has been identified as a 90 kDa disulphide-linked heterodimer composed of two glycoproteins termed alpha and beta. More recently, another type of T cell receptor for antigen has been described, which seems to mediate killing of target cells without any obvious requirement for MHC recognition. This T cell receptor for antigen is also a heterodimer composed of gamma, delta chains non-covalently associated with the three mon morphic CD3 subunits. Another disulphide-linked dimer capable of triggering T lymphocytes has been defined recently by a monoclonal antibody: the anti-human 9.3 antigen. In order to generate monoclonal or polyclonal reagents against variable and constant regions of the T cell receptor chains and against new epitopes of the 9.3 antigen, we have developed a biochemical method of purification of T lymphocyte disulphide-linked dimers. Our method relies on two biochemical properties of the 9.3 surface molecule and the T cell receptor for antigen. (1) They are disulphide-linked dimers and thus can be separated from the vast majority of the cell surface molecules by two-dimensional (non-reduced versus reduced) sodium dodecyl sulphate-polyacrylamide gel electrophoresis (SDS-PAGE). (2) T cell receptor chains are less hydrophobic than the 9.3 antigen, and thus can be isolated from it on reverse-phase high-performance liquid chromatography (HPLC) at a lower concentration of acetonitrile. Microsomal preparations from T cell clones and leukaemia lines were prepared by nitrocavitation and lysed in sodium deoxycholate. After concentration, this lysate was electrophoresed on SDS-PAGE in non-reducing conditions. The gel slice corresponding to the molecular weight of the T cell receptor was cut out and run in reducing conditions in the second dimension. The T cell receptor spots were easily located on the gel by autoradiography as the microsomal lysate had been mixed with iodinated glycoproteins. The T cell receptor was eluted from the gel with about 85% yield. At this stage, the T cell receptor preparations also contained the 9.3 antigen, another disulphide-linked dimer. The separation of this antigen from the T cell receptor chains had been achieved on reverse-phase HPLC. This procedure allows the purification and separation of two disulphide-linked dimers which are both involved in T cell activation. The obtention of antibodies against new epitopes of these important molecules would be extremely useful for analysing their role in T cell function and ontogeny.
 ...
PMID:Biochemical purification of various receptor molecules involved in human T lymphocyte activation. Separation of 9.3 antigen from the T cell receptor for antigen. 325 22

The feasibility of the use of reverse-phase high-performance liquid chromatography (RP-HPLC) for detecting differences in the protein phenotypes of highly purified fractions of normal and chronic myelogenous leukemic (CML) mature granulocytes isolated from peripheral blood was determined. At least 21 protein peaks were consistently and reproducibly detected in the RP-HPLC profiles of acetonitrile-trifluoroacetic acid extracts of normal granulocytes. This assay takes only 60 minutes to perform and can be done on 4 X 10(6) granulocytes (approximately the number of granulocytes in 1 ml normal blood). Furthermore, sodium dodecyl sulfate-gel electrophoresis of the RP-HPLC fractions provides a second dimension to the analysis of the polypeptide pattern of these cell lysates. Analyses of subcellular fractions by these methods revealed that most of the major peaks in the RP-HPLC profiles of intact granulocytes originate mainly from the granule and membrane fractions. Although the protein phenotypes of mature granulocytes were remarkably uniform among normal individuals, those of mature granulocytes obtained from the blood of CML patients were consistently abnormal and varied considerably among individual patients. The results indicate that the approach used here could have useful application in the study of abnormal granulocyte differentiation in leukemia.
 ...
PMID:Direct analysis of differentiation proteins in normal and leukemic human granulocytes by high-performance liquid chromatography. 386 Jun 80

Experiments were performed to examine a growth-promoting activity on B cells or B leukemic cells of T cell-replacing factor (TRF) produced by a murine T cell hybridoma (B151K12) which constitutively produces TRF. The cellfree supernatant (CFS) from B151K12 cells (B151-CFS) could induce terminal differentiation of pre-activated B cells or in vivo passaged chronic B leukemia cells, BCL1, into immunoglobulin-secreting cells, while it did not exert a nominal lymphokine activity such as BCGFI (now known as BSFpl), IL 2, or gamma-interferon. However, it promoted [3H]thymidine uptake of dextran sulfate (DXS)-stimulated normal B cells and in vivo passaged BCL1 cells, suggesting that it also has BCGFII activity. We tried extensively to purify and to separate the TRF active molecule from the BCGFII active molecule by using many types of purification procedures. The purification scheme consisted of ammonium sulfate precipitation, DEAE-cellulose chromatography, Blue-Sepharose chromatography, hydroxylapatite chromatography, and gel permeation with fast protein liquid chromatography (FPLC). It was revealed that the BCGFII active molecule was hardly separable from the TRF during the entire purification procedure. The TRF as well as BCGFII active materials were glycoprotein with an apparent m.w. of 50 to 60 Kd on gel permeation chromatography and 18 Kd on SDS-PAGE under reducing conditions. The BCGFII active materials were hardly separable from the TRF active one, even after a reverse-phase FPLC, in which both BCGFII and TRF activities were recovered in the fractions eluted at 44 to 48% acetonitrile in 0.1% trifluoroacetic acid (TFA). Furthermore, the absorption of TRF and BCGFII active materials by using BCL1 cells removed not only TRF but also BCGFII activity. Moreover, B cell-specific monoclonal antibody (9T1), which can preferentially block TRF-dependent plaque-forming cell responses, also inhibited the expression of BCGFII activity to BCL1 cells. Taking all of the results together, we conclude that the TRF from B151K12 cells promotes growth of appropriately activated, such as DXS-stimulated normal cells and BCL1 tumor cells. These results suggest that B151-TRF may act on B cells as B cell growth and differentiation factors.
 ...
PMID:BCGFII activity on activated B cells of a purified murine T cell-replacing factor (TRF) from a T cell hybridoma (B151K12). 387 7

The myelosuppressive effects of human chemokines were evaluated in vitro on normal myeloid progenitors obtained from bone marrow and cord blood, on bone marrow progenitors from patients with acute or chronic leukemia, on proliferation of human factor-dependent cell line M07e, and in vivo on myelopoiesis in mice. Preincubation of human MIP-1 alpha, MIP-2 alpha, interleukin (IL)-8, platelet factor (PF) 4, monocyte chemotactic and activating factor (MCAF), and interferon-inducible protein-10 (IP-10) in an acetonitrile (ACN) solution significantly enhanced the specific activity of these chemokines for in vitro suppression of granulocyte-macrophage (CFU-GM), erythroid (BFU-E), and multipotential (CFU-GEMM) progenitor cells stimulated to proliferate with a colony stimulating factor plus steel factor (SLF). Combinations of any two of these ACN-treated chemokines synergized to suppress colony formation of CFU-GM, BFU-E, and CFU-GEMM at chemokine concentrations below that at which combinations of non-ACN treated chemokines are active. Cord blood progenitors, as previously reported, were in a slow or noncycling state and nonresponsive to inhibition by chemokines. However, after suspension culture with GM-CSF, IL-3, and SLF, they were placed into rapid cell cycle and were responsive to inhibition by ACN-treated chemokines. Low doses of these ACN-pretreated chemokines were active in vivo in suppressing absolute numbers and cycling status of femoral marrow CFU-GM, BFU-E, and CFU-GEMM in C3H/HeJ mice. Other chemokines, alone and in combination, including MIP-1 beta, MIP-2 beta, GRO-alpha NAP-2, and RANTES, were inactive in vitro and in vivo whether or not they were pretreated with ACN. While heterogeneity in responsiveness of CFU-GM from different patients with leukemia to suppression by ACN-treated chemokines was apparent, if the patients had CFU-GM responsive to one of the active chemokines these cells were responsive to the other active chemokines; if patient CFU-GM were not responsive to one of the chemokines, they were not responsive to the other active chemokines. M07e colony-forming cells were responsive to the growth-inhibiting effects of the active ACN-treated chemokines, alone and in combination, but these effects were rapidly reversible and sustained only by multiple daily additions of chemokines. These results should be of value in considering these chemokines for potential clinical use and for assessment of their mechanisms of action, alone and in combination.
 ...
PMID:Human chemokines: enhancement of specific activity and effects in vitro on normal and leukemic progenitors and a factor-dependent cell line and in vivo in mice. 749 26

Based upon previously discovered antileukemic properties of 9-beta-D-fucopyranosyladenine (1) in cell culture, four new nucleosides containing naturally occurring bases have been prepared from D-fucose. alpha-D-Fucopyranose tetraacetate was condensed with the silylated bases in either acetonitrile or 1,2-dichloroethane with tin(IV) chloride as the catalyst. The intermediate blocked nucleosides were obtained in crystalline form and deacetylated with methanolic sodium methoxide. 1-beta-D-Fucopyranosyluracil (8), 1-beta-D-fucopyranosylthymine (9), 1-beta-D-fucopyranosylcytosine (10) as the hydrochloride salt, and 7-beta-D-fucopyranosylguanine (11) were crystallized, and their structures were verified by spectroscopic techniques. Nucleosides 8 and 9 had only borderline activity against leukemia L1210 cells grown in culture, whereas nucleoside 11 had activity equal to 1. However, nucleoside 10 proved to be twice as active as either 1 or 11. The antileukemic activity, which was due to the inhibition of cell division, was reversible by transfer of the arrested cells to fresh media or by the addition of cytidine.
 ...
PMID:Synthesis and antileukemic activity of certain D-fucopyranosyl nucleosides. 834 53


1 2 3 4 Next >>