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

Primitive malignant progenitors defined as nonobese diabetic/severe combined immunodeficient (NOD/SCID) leukemia-initiating cells or NOD/SL-IC from patients with acute myeloid leukemia (AML) can be detected and quantitated in sublethally irradiated NOD/SCID mice. However, there is variability in the levels of bone marrow (BM) engraftment obtained after intravenous injection of cells from different AML samples. In the current study, AML cell engraftment in standard NOD/SCID mice was compared to that obtained with NOD/SCID mice transgenic for the human growth factor genes Steel factor (SF), interleukin-3 (IL-3) and granulocyte macrophage-colony-stimulating factor (GM-CSF) (N/S-S/GM/3) as well as beta 2 microglobulin-null NOD/SCID (N/S-beta 2m(-/-)) mice. Three of the eight AML samples that failed to engraft in standard NOD/SCID animals showed easily detectable and up to 70-fold increased in the number of leukemic cells in BM 8-12 weeks post-transplantation in each of the N/S-beta 2m(-/-) and N/S-S/GM/3 mouse strains. In two of the four AML samples studied at limiting dilution, the frequency of NOD/SL-IC detected was increased six- and seven-fold. Thus, in these novel mouse strains a broader spectrum of AML patient samples can be evaluated for their progenitor content and potentially studied for their response to innovative therapeutics in vivo.
Leukemia 2003 Apr
PMID:Improved engraftment of human acute myeloid leukemia progenitor cells in beta 2-microglobulin-deficient NOD/SCID mice and in NOD/SCID mice transgenic for human growth factors. 1268 34

We established a novel experimental model for human T-cell leukemia virus type 1 (HTLV-1)-induced tumor using NOD-SCID/gammac(null) (NOG) mice. This model is very useful for investigating the mechanism of tumorigenesis and malignant cell growth of adult T-cell leukemia (ATL)/lymphoma, which still remains unclear. Nine HTLV-1-infected cell lines were inoculated subcutaneously in the postauricular region of NOG mice. As early as 2 to 3 weeks after inoculation, seven cell lines produced a visible tumor while two transformed cell lines failed to do so. Five of seven lines produced a progressively growing large tumor with leukemic infiltration of the cells in various organs that eventually killed the animals. Leukemic cell lines formed soft tumors, whereas some transformed cell lines developed into hemorrhagic hard tumors in NOG mice. One of the leukemic cell lines, ED-40515(-), was unable to produce visible tumors in NOD-SCID mice with a common gamma-chain after 2 weeks. In vivo NF-kappaB DNA binding activity of the ED-40515(-) cell line was higher and the NF-kappaB components were changed compared to cells in vitro. Bay 11-7082, a specific and effective NF-kappaB inhibitor, prevented tumor growth at the sites of the primary region and leukemic infiltration in various organs of NOG mice. This in vivo model of ATL could provide a novel system for use in clarifying the mechanism of growth of HTLV-1-infected cells as well as for the development of new drugs against ATL.
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PMID:Rapid tumor formation of human T-cell leukemia virus type 1-infected cell lines in novel NOD-SCID/gammac(null) mice: suppression by an inhibitor against NF-kappaB. 1269 30

The use of recombinant vectors based on wild-type viruses that are absent in humans and are not associated with any disease in their natural animal hosts or in accidentally infected humans would add an additional level of safety for human somatic gene therapy approaches. These criteria are fulfilled by foamy viruses (FVs), a family of complex retroviruses whose members are widely found among mammals and are apathogenic in all hosts. Here, we show by comparison of identically designed vector constructs that recombinant retroviral vectors based on FVs were as efficient as lentiviral vectors in transducing nonobese diabetic/severe combined immunodeficiency (NOD/SCID) mice repopulating human CD34(+) cord blood (CB) cells. The FV vector was able to achieve gene transfer levels up to 84% of engrafted human cells in a short overnight transduction protocol. In contrast, without prestimulation of the target cells, a human immunodeficiency virus type 1 (HIV-1)-based lentiviral vector pseudotyped with gibbon ape leukemia virus envelope (GALV Env) was nearly as inefficient as murine leukemia virus (MLV)-based oncoretroviral vectors in transducing NOD/SCID repopulating cells. The same HIV vector pseudotyped with the vesicular stomatitis virus glycoprotein G (VSV-G) achieved high marking efficiency. Clonality analysis of bone marrow samples showed oligoclonal hematopoiesis with single to multiple insertions per cell, both for FV and HIV vectors. These data demonstrate that vectors based on FVs warrant further investigation and development for medical use.
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PMID:Comparison of three retroviral vector systems for transduction of nonobese diabetic/severe combined immunodeficiency mice repopulating human CD34+ cord blood cells. 1271 62

Human natural killer (NK) and NK T cells play an important role in allogeneic bone marrow (BM) transplantation and graft-versus-leukemia (GVL) effect. The mechanisms by which these cells home to the BM and spleen are not well understood. Here we show that treatment of these cells with pertussis toxin and neutralizing antibodies to the chemokine receptor CXCR4 inhibited homing of the cells to the BM, but not the spleen, of NOD/SCID mice. The retention of NK and NK T cells within the spleen and BM was dependent on Galphai signaling and CXCR4 function. The chemokine receptors CXCR4 and CXCR3 are expressed predominantly on the cell surface of NK T cells. Following activation with interleukin-2 (IL-2), the levels of CXCR4 on NK and NK T cells decreased significantly. Treatment of cells with IL-2 inhibited their migration in response to CXCL12 and their homing and retention in the BM and spleen of NOD/SCID mice. In contrast to CXCR4, the expression levels of the chemokine receptor CXCR3 and the migration of cells in response to CXCL9 and CXCL10 increased after IL-2 treatment. Thus, down-regulation of CXCR4 and up-regulation of CXCR3 may direct the trafficking of cells to the site of inflammation, rather than to hematopoietic organs, and therefore may limit their alloreactive potential.
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PMID:Involvement of CXCR4 and IL-2 in the homing and retention of human NK and NK T cells to the bone marrow and spleen of NOD/SCID mice. 1273 Jan 2

There have been controversies about CD34 and CD38 expression by human cord blood (CB) stem cells. Using the newborn NOD/SCID/beta2-microglobulin-null mouse assay that we recently developed, we examined the in vivo engrafting capability of human CB cells. Almost all of the 4-5 months engrafting cells were found in CD34(+) population. The capability of secondary reconstitution was found only in the CD34(+) cells. When the CD34(+) CB cells were separated into CD38(-) and CD38(+) subpopulations and tested for engraftment, the majority of the engrafting cells were detected in the CD38(-) subpopulation. These findings are consistent with the results from studies of murine stem cells and strongly indicate that the phenotype of human CB stem cells is CD34(+) CD38(-).
Leukemia 2003 May
PMID:Human cord blood long-term engrafting cells are CD34+ CD38-. 1275 Jul 10

Imatinib mesylate, a competitive inhibitor of Abl tyrosine kinase, is highly effective for the early stages of chronic myelogenous leukemia (CML), but remissions induced in advanced-phase CML and Philadelphia chromosome-positive (Ph+) acute lymphoblastic leukemia tend to be relatively short-lived. Therefore, the search for agents that enhance the anti-Ph+ effect of imatinib mesylate is warranted. We investigated the combined effects of imatinib mesylate and the third-generation bisphosphonate zoledronate (ZOL) on Ph+ leukemias, because ZOL inhibited the prenylation of Ras-related proteins downstream of Bcr/Abl. First, we identified the potency of ZOL in vitro against human leukemic cell lines, including 2 Ph+ and a P-glycoprotein-overexpressing leukemic cell line. ZOL was also effective in vivo because as it prolonged the survival of nonobese diabetic/severe combined immunodeficient (NOD/SCID) mice who were given xenografts with Ph+ BV173 leukemic cells. Next, we showed the in vitro synergistic effects with ZOL and imatinib mesylate for Ph+ cell lines. ZOL combined with imatinib mesylate showed synergistic effects in vivo that prolonged the survival of mice inoculated with BV173. ZOL only minimally inhibited the growth of normal hematopoietic progenitors in vitro, and mice receiving ZOL or imatinib mesylate or both tolerated these treatments well. These findings indicate that ZOL is a potent antileukemic agent that augments synergistically the anti-Ph+ leukemia activity of imatinib mesylate.
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PMID:The third-generation bisphosphonate zoledronate synergistically augments the anti-Ph+ leukemia activity of imatinib mesylate. 1276 30

Nectins are recently described adhesion molecules that are widely expressed on many tissues, including the hematopoietic tissue. Nectin 1 (CD111) is expressed on a higher proportion of mobilized peripheral blood (mPB) than cord blood (CB) CD34+ cells, and of CD34+/CD38+ cells when compared with CD34+/CD38- cells. We studied functional properties of human CB and mPB CD34+ cells that express low or high levels of CD111. CD34+/CD111(dim) cells contain a higher proportion of cells in G0/G1 phase than CD34+/CD111(bright) cells. CD34+/CD111(bright) cells contain more erythroid progenitors: CFU-E, than their counterparts, which on the opposite contain more HPP-CFC. Limiting dilution analyses demonstrate a higher frequency of immature progenitors: cobblestone-area colony-forming cells, CD34+/CD111(dim) than in CD34+/CD111(bright) cells. In vitro differentiation assays demonstrate a higher frequency of B-, T- and dendritic-cell precursors, but less NK-cell precursors in CD34+/CD111(dim) cells. Evaluation of engraftment in NOD-SCID mice shows that SCID repopulating cells are more frequent among mPB CD34+/CD111(dim) cells. Liquid culture of CD34+/CD111(dim) cells with erythropoietin shows that CD111 expression increases simultaneously with CD36, following CD71 and before glycophorin A expression. In conclusion, immature human hematopoietic progenitors express low levels of CD111 on their surface. During erythroid differentiation CD34+ cells acquire higher levels of the CD111 antigen.
Leukemia 2003 Jun
PMID:Functional characterization of human CD34+ cells that express low or high levels of the membrane antigen CD111 (nectin 1). 1276 81

A novel cell line, SACHI, was established from a pericardial effusion developed during the course of primary plasma cell leukemia (PCL). The cell line SACHI cells were the same as the infiltrating plasma cells with regard to surface markers (CD38(+)CD19(-)PCA-1(+)VLA-5(-)CD56(-)TdT(+)) and immunoglobulin gene rearrangements. Analysis of SACHI cells showed a complex hypertriploid (karyotype mode 70-73) including 7p32, 14q32, and Xq24 structural abnormalities, which were found also in the original leukemia cells. Dual-color fluorescence in situ hybridization revealed that the c-MYC gene was juxtaposed with a constant region of IgG (Cgamma) on 14q32. The split Cgamma locus was fused near the MAFB gene on chromosome 20. The SACHI cells had increased amounts of c-MYC and MAFB transcripts. Injection of SACHI cells into NOD/SCID mice generated leukemic plasmacytosis with invasion to liver, spleen, and bone marrow. This cell line may be useful for therapeutic testing as well as analyzing the molecular pathogenesis of PCL.
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PMID:A xeno-transplantable plasma cell leukemia line with a split translocation of the IgH gene. 1281 Feb 53

The human hematopoietic stem cell compartment is comprised of repopulating CD34(+) and CD34(-) cells. The interaction between these subsets with respect to their reconstitution capacity in vivo remains to be characterized. Here, lineage-depleted (Lin(-)) human CD34(+) and CD34(-) hematopoietic cells were isolated from human male and female umbilical cord blood (CB) and transplanted into immune-deficient NOD/SCID EMV(null) mice, thereby allowing the use of human and Y-chromosome-specific DNA sequences to discriminate human reconstitution contributed by CD34(+) vs CD34(-) repopulating stem cells. Although cultured human CB CD34(-)Lin(-) cells transplanted alone possessed only minimal repopulating capacity, with 15% of mice achieving low levels of engraftment, transplantation of cocultured male CD34(-)Lin(-) cells with female CD34(+)Lin(-) cells demonstrated human repopulation with a contribution from CD34(-)Lin(-)-derived progeny in 80% of the recipients. After coculture and transplantation, male CD34(-)Lin(-) cells gave rise to primitive CD34(+)CD38(-) cells isolated in vivo, which demonstrated clonogenic progenitor function into multiple lineages. Taken together, our study indicates that the presence of CD34(+)Lin(-) cells in coculture enhanced the low repopulating function of human CD34(-)Lin(-) cells in vivo. We propose that CD34(+)Lin and CD34(-)Lin cells represent phenotypically distinct, but related cell types that exhibit unique and previously unappreciated functional interaction.
Leukemia 2003 Aug
PMID:Coculture and transplant of purified CD34(+)Lin(-) and CD34(-)Lin(-) cells reveals functional interaction between repopulating hematopoietic stem cells. 1288 51

The aim of our study was to characterise, for the first time, the chemo- and radiation sensitivity of seven pediatric acute lymphoblastic leukemias xenotransplanted into immunodeficient NOD/SCID mice and to correlate the findings with the expression of three drug resistance proteins, P-glycoprotein (P-gp), multidrug resistance-associated protein (MRP1) and lung resistance protein (LRP). Mice were treated with single drugs used in clinical protocols: daunorubicin, doxorubicin, cyclophosphamide, vincristine, cytarabine, asparaginase and methotrexate. Two ALL samples, established from primarily diagnosed patients, responded to 5 or 6 of the tested cytostatics, respectively, while 3 out of 5 ALLs from relapse patients were only sensitive towards 2-4 drugs tested. Daunorubicin was more efficient than doxorubicin. The response of xenografted ALL toward vincristine and cyclophosphamide was inversely correlated with the expression of P-gp, LRP and MRP1 (R2 = 0.71, 0.70 and 0.64 for vincristine and 0.44, 0.70 and 0.60 for cyclophosphamide). A good correlation could be detected between the expression of P-gp and LRP (R2 = 0.88), P-gp and MRP1 (R2 = 0.75) and LRP and MRP1 (R2 = 0.90). The highest co-expression of the drug resistance proteins in the leukemia ALL-SCID 6 coincided with a high resistance to radiation and chemotherapy. Prediction of the individual drug resistance profile of a patient on the basis of results from the ALL-SCID xenograft studies was not possible because of the relatively long time necessary and because of the changes in the expression of P-gp, LRP and MRP1 during the murine generations. We conclude that in the drug resistance phenotype of ALL not only the above mentioned proteins but a variety of different molecules are involved.
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PMID:Chemo- and radiation sensitivity of xenografted acute lymphoblastic leukemias--correlation to the expression of multidrug resistance proteins. 1289 54


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