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)

Flow cytometry was used to detect fibrinogen (platelet associated fibrinogen: PAFbg) and fibronectin (PAFn) on the surface membrane of platelets in leukemia (9 cases), lung cancer (15 cases) and hepatoma (8 cases) patients (by one color analysis method), and simultaneously to investigate the binding of monoclonal anti-glycoprotein (GP) IIb/IIIa and anti-GP Ib antibodies (by two color analysis). All patient groups showed higher Fbg values than the normal control group, but no differences were found between patient groups. The values of Fbg and Fn showed a correlation, but the pattern of binding did not show a regular tendency in any patient group. There also was no significant correlation between Fbg values and the positive percentage of monoclonal anti-GPIIb/IIIa and anti-GPIb antibodies, and the binding of Fbg did not inhibit that of monoclonal antibody. The results suggest the following. 1. There are no differences in platelet activation in leukemia, lung cancer and hepatoma patients, and the degree of platelet activation is decided by the degree and the kind of stimulation. 2. The increase of both PAFbg and PAFn prove to the existence of activated platelet.
 ...
PMID:[Analysis of adhesive proteins on the surface membrane of platelet in malignant neoplasm]. 232 78

We measured concentrations of fibronectin (FN) in the cerebrospinal fluid (CSF) in long-term follow-up patients with acute lymphoblastic leukemia (ALL). In 11 patients with neuroleukemia the CSF-FN level was elevated already at the time of diagnosis of ALL, 3.8 +/- 0.6 mg/l, increased during therapy to 4.7 +/- 0.5 mg/l, and at the time of concurrent blast cell finding it was 5.5 +/- 1.0 mg/l. In 11 patients with no subsequent CNS leukemia, the mean CSF-FN level was 2.4 +/- 0.6 mg/l at the time of diagnosis of ALL and 2.8 +/- 0.6 mg/l during therapy, and increased to 3.2 +/- 0.8 mg/l. The neuroleukemia rate was 43% in patients with initial CSF-FN levels greater than 2 mg/l, compared with 5% in patients with CSF-FN levels less than or equal to 2 mg/l (p less than 0.005) in a group of 45 long-term follow-up patients with ALL. Regression analysis on the 21 clinical or laboratory parameters studied showed that the only variable independently associated with CSF-FN was the total protein concentration in the CSF; this, however, explained only 14% of the observed variation in the CSF-FN concentration and did not show any correlation with CNS involvement. We conclude that the CSF-FN test at diagnosis of ALL showed significant differences between groups of patients with and without CNS leukemia, and may prove to be a new early marker for neuroleukemia.
 ...
PMID:Fibronectin concentration in cerebrospinal fluid reflects early central nervous system involvement in children with acute lymphoblastic leukemia. 234 67

Rous sarcoma virus-transformed BHK cells (RSV/B4-BHK) adhere to a fibronectin-coated substratum primarily at specific dot-shaped sites. Such sites contain actin and vinculin and represent close contacts with the substratum as revealed by interference reflection microscopy. Only a few adhesion plaques and actin filament bundles can be detected in these cells as compared to untransformed parental fibroblasts. In thin sections examined with transmission electron microscopy (TEM) these adhesion sites correspond to short protrusions of the ventral cell surface that contact the substratum at their apical portion. These structures, which may represent cellular feet, are therefore called podosomes. By screening a number of different transformed fibroblasts plated on a fibronectin-coated substratum we find that podosomes are common to mammalian and avian cell lines transformed either by Rous sarcoma virus (RSV) or by Fujinami avian sarcoma virus (FSV), whose oncogenes encode specific tyrosine kinases. Using antibodies reacting with phosphotyrosine in immunofluorescence experiments, we show that phosphotyrosine-containing molecules are concentrated in podosomes. Podosomes are not detected in fibroblasts transformed by other retroviruses (Snyder-Theilen sarcoma virus, Abelson leukemia virus and Kirsten sarcoma virus) or by DNA tumor viruses (polyoma, SV40), indicating that podosome-mediated adhesion in transformed fibroblasts is related to the peculiar properties of some oncoproteins and possibly to their tropism for adhesion systems. Podosomes and adhesion plaques, although similar in cytoskeletal protein composition, have different mechanisms and kinetics of formation. Assembly of podosomes, in fact (i) does not require fetal calf serum (FCS) in the adhesion medium, that is necessary for the organization of adhesion plaques; (ii) does not require protein synthesis; and (iii) is insensitive to the ionophore monensin, that prevents adhesion plaque formation. Moreover, during attachment to fibronectin-coated dishes, podosomes appear in the initial phase (60 min) of attachment, while adhesion plaques require a minimum of 180 min. In conclusion podosomes of RSV- and FSV-transformed fibroblasts represent a phenotypic variant of adhesion structures.
 ...
PMID:Rous sarcoma virus-transformed fibroblasts adhere primarily at discrete protrusions of the ventral membrane called podosomes. 241 76

The amino acid sequence of the vitronectin receptor alpha subunit deduced from cDNA is presented. The sequence defines a 1047-amino-acid polypeptide precursor with a putative signal sequence, a large extracellular domain with several sites homologous to calcium binding sites in other proteins, a transmembrane domain, and a 32-amino-acid cytoplasmic domain. The 7-kilobase vitronectin receptor alpha subunit mRNA was found to be expressed in all cell lines examined, including endothelial cells, K562 and HEL leukemia cells, and osteosarcoma cells. In the two leukemia cell lines, the expression of the vitronectin receptor mRNA, as well as that of the fibronectin receptor, was enhanced in the presence of phorbol ester, a treatment known to increase the adhesiveness of these cells. The HEL cells were the only ones among the cell lines tested that also contained the mRNA of the platelet adhesion receptor alpha subunit, glycoprotein IIb. The expression of glycoprotein IIb was slightly enhanced by treatment of the cells with phorbol ester. These results complete the partial cDNA sequence of the vitronectin receptor alpha subunit published previously (Suzuki, S., Argraves, W. S., Pytela, R., Arai, H., Krusius, T., Pierschbacher, M. D., and Ruoslahti, E. (1986) Proc. Natl. Acad. Sci. U.S.A., 83, 8614-8618), confirm that the vitronectin receptor, and not IIb, is expressed in endothelial cells, and show that changes in the level of its expression correlate with changes in cell adhesiveness.
 ...
PMID:Amino acid sequence of the vitronectin receptor alpha subunit and comparative expression of adhesion receptor mRNAs. 244

In the present study plasma fibronectin levels were determined in patients with hematopoietic malignancy, particularly leukemias, in an effort to clarify their clinical implications. Among leukemia patients, those with AML, ALL, ATL or CLL had various plasma fibronectin levels that were higher in some cases, while lower in others, as compared to normal control values. An elevation of the fibronectin level was noted often in APL, while lower fibronectin values were observed in many instances of CML. In these types of leukemia, acute exacerbation as well as supervention of infection tended to be associated with lower than normal levels of fibronectin. An especially marked depression of fibronectin occurred, when leukemia was complicated by sepsis or DIC, in which a good parallel was noted between the progress of disease and the fibronectin level. In lymphoproliferative diseases, the fibronectin value varied widely, but low fibronectin levels were frequently associated with intercurrent infection or an extreme deterioration of the general physical conditions.
 ...
PMID:Variation of plasma fibronectin levels in leukemia patients. 248 45

Glomerular visceral epithelial cells (GVEC) from normal human glomeruli were grown in tissue culture. Cell surface markers were studied by immunofluorescence microscopy using antibodies against lymphohaemopoietic differentiation antigens which are known to be present early (BA-1, OKB2, BA-2) and late (J5, anti CR1) in renal ontogenesis. Like foetal human glomerular epithelium, the cultured cells reacted with BA-1 and OKB2 (identifying an antigen expressed on B cells and polymorphonuclear leucocytes), and BA-2 (leukaemia-associated antigen), but were consistently negative for CR1 (C3b receptor); J5 which identifies the common acute lymphoblastic leukaemia antigen (CALLA) stained variably. Reactivity with antimyosin or anti factor VIII were absent. The cells produced an extracellular matrix containing laminin, type IV collagen, and fibronectin. This study supports the notion that GVEC undergo dedifferentiation as shown by the acquisition of lymphohaemopoietic differentiation antigens present early in renal ontogeny. In addition, the production of extracellular matrix constituents in vitro may be useful for the investigation of human glomerular basement membranes.
 ...
PMID:Lymphohaemopoietic antigens of cultured human glomerular epithelial cells. 264 19

We investigated whether the concentration of fibronectin (FN) in the cerebrospinal fluid (CSF) could be used for identifying patients with subclinical blast-cell infiltration in the central nervous system (CNS) and an increased risk of CNS relapse later in the course of their leukemia. Our series comprised 36 children with newly diagnosed acute lymphoblastic leukemia (ALL). The mean follow-up time was 54 months (range 5 to 96 months). The median concentration of CSF-FN at diagnosis was 2.24 mg/l (range 0.78 to 7.04 mg/l). The 3-year continuous complete remission rate for the 16 patients with CSF-FN concentrations less than or equal to 2 mg/l was 93% as compared with 37% for the 19 patients with CSF-FN greater than 2 mg/l (p = 0.001). When multivariate analysis was performed, the CSF-FN concentration retained its prognostic significance. When all relapses were considered as failures, the relative risks of relapse for patients with CSF-FN less than or equal to 2 mg/l and greater than 2 mg/l were I and 15.8 (95% confidence limits 1.8-135.6, p less than 0.02), respectively. If only CNS relapses (isolated and combined) were considered as failures, relative risks for the above-mentioned groups were I and 11.6 (1.4-99.5, p less than 0.05), respectively. We conclude that determination of the CSF-FN concentration may provide a new means of evaluating the CSF in children with ALL and may prove to be a sensitive indicator of leukemic CNS infiltration.
 ...
PMID:Elevated cerebrospinal fluid fibronectin concentration at diagnosis indicates poor prognosis in children with acute lymphoblastic leukemia. 291 Aug 30

The plasma membrane of murine erythro-leukemia (MEL) cells contains a 140-kD protein that binds specifically to fibronectin. A 125I-labeled 140-kD protein from surface-labeled uninduced MEL cells was specifically bound by an affinity matrix that contained the 115-kD cell binding fragment of fibronectin, and specifically eluted by a synthetic peptide that has cell attachment-promoting activity. The loss of this protein during erythroid differentiation was correlated with loss of cellular adhesion to fibronectin. Both MEL cells and reticulocytes attached to the same site on fibronectin as do fibroblasts since adhesion of erythroid cells to fibronectin was specifically blocked by a monoclonal antibody directed against the cell-binding fragment of fibronectin and by a synthetic peptide containing the Arg-Gly-Asp-Ser sequence found in the cell-binding fragment of fibronectin. Erythroid cells attached specifically to surfaces coated either with the 115-kD cell-binding fragment of fibronectin or with the synthetic peptide-albumin complex. Thus, the erythroid 140-kD protein exhibits several properties in common with those described for the fibronectin receptor of fibroblasts. We propose that loss or modification of this protein at the cell surface is responsible for the loss of cellular adhesion to fibronectin during erythroid differentiation.
 ...
PMID:The fibronectin receptor on mammalian erythroid precursor cells: characterization and developmental regulation. 293 41

We describe the isolation of human fibronectin receptors (integrins) from two nonadherent promonocytic cell lines and from peripheral blood monocytes. Integrins purified from U-937 and THP-1 cells exhibited identical electrophoretic migrations on sodium dodecyl sulfate gels run under reducing (approximately Mr 150,000) and nonreducing (alpha, Mr 160,000; beta, Mr 130,000) conditions. Treatment of U-937 or THP-1 cells with phorbol esters induced these cells to express different integrins with electrophoretic mobilities (alpha, Mr 140,000; beta, Mr 115,000, nonreduced) identical to those from normal human peripheral blood monocytes. Receptors isolated from uninduced, nonadherent promonocytic leukemia cells (U-937 and THP-1) were distinct from glycoproteins IIb and IIIa and from leukocyte adhesion molecules (p150/95). However, receptors isolated here did react with an antibody known to block cell adhesion to fibronectin. The differences observed in apparent molecular masses of fibronectin receptors from uninduced and induced U-937 or THP-1 cells are removed by treatment of purified integrins with endoglycosidase F or N-glycanase. In summary, the data presented here demonstrate the purification of integrins by fibronectin affinity chromatography from human leukemia cells and normal peripheral blood monocytes. Our results suggest that these receptors differ in immature and mature monocytic cells, and are altered by glycosylation in the course of cellular maturation.
 ...
PMID:Alteration of fibronectin receptors (integrins) in phorbol ester-treated human promonocytic leukemia cells. 297 31

Human hemopoietic blast colony-forming cells (BI-CFCs) recognize and adhere to the extracellular matrix (ECM) produced by marrow-derived stromal cells in vitro. We have investigated the requirements for this interaction by testing the capacity of BI-CFCs to adhere to ECM components under a variety of conditions. Binding was prevented completely by prior treatment of stromal ECM with nitrous acid, in large part by treatment with heparitinase or hyaluronidase, and slightly by treatment with chondroitinases. Whereas heparan sulfate isolated from marrow stromal cultures effectively blocked binding, heparan sulfate from bovine kidney did not. Chondroitin sulfate and hyaluronic acid did not have any effect in this test. In contrast, collagen was not sufficient for the interaction because dishes coated with collagen type I or IV did not act as adhesive surfaces for BI-CFCs. Ligands for integrin receptors (e.g., fibronectin) did not participate in BI-CFC binding because the synthetic pentapeptide glycine-arginine-glycine-asparagine-serine did not compete with stroma in binding BI-CFCs. These findings indicate that heparan sulfate in the bone marrow microenvironment is necessary for BI-CFC binding to ECM and may contribute to localizing hemopoietic stem cells in hemopoietic tissue.
Leukemia 1988 Dec
PMID:Heparan sulfate is necessary for adhesive interactions between human early hemopoietic progenitor cells and the extracellular matrix of the marrow microenvironment. 297 4


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