ABSTRACT
<p><b>OBJECTIVE</b>To explore the expression, characteristics and roles of macrophage colony-stimulating factor receptor (M-CSF-R) in human leukemia cell lines.</p><p><b>METHODS</b>Peripheral blood mononuclear cells (PBMCs) collected from 3 healthy persons, cord blood mononuclear cells (CBMCs) collected from 5 healthy persons and 4 human myelomonocytic leukemia cell lines including J6-1, J6-2, K562 and HL-60 were studied by using ABC immunoperoxidaes assay, indirect immunofluorescene staining, flow cytometry, and Western blot.</p><p><b>RESULTS</b>M-CSF-R was noticed to be localized in the cytoplasm, nucleus and at the membrane in 4 human leukemia cell lines; expression of M-CSF-R was not detected in normal human PBMCs without PHA stimulation. Human PBMCs stimulated by PHA expressed a low level of M-CSF-R. Frequencies of membrane bound M-CSF-R (M-CSF-mR) expression in J6-1, J6-2, K562 and HL-60 were 78.9%, 72.6%, 54.9% and 58.0% respectively. Frequencies of cytoplasm and nucleus associated M-CSF-R (M-CSF-cnR) were 52.3%, 44.3%, 28.0% and 65.3% respectively. One form of M-CSF-R with a molecular weight of 120 000 was detected both in the cytoplasm and nucleus of HL-60 cells. The half-life of M-CSF-cnR in leukemia cells mentioned above was longer than that of corresponding M-CSF-R in stimulated CBMCs, and the half-life of M-CSF-mR in leukemia cells was extended except that of M-CSF-mR in K562 cells. Both anti-M-CSF-R monoclonal antibody and recombinant human M-CSF soluble receptor could cause the growth arrest of HL-60 cell in G(0)/G(1) phase, and could inhibit the formation of colony of HL-60 cell in soft agarose.</p><p><b>CONCLUSIONS</b>Expression of M-CSF-R in leukemia cells is heterogeneous. The accumulation of cellular M-CSF-R results in the low degradation rate of cellular M-CSF-R in leukemia cells, which could be a potential mitotic signal. Signal mediated by M-CSF-R is important and necessary for the growth of HL-60 cell.</p>
Subject(s)
Humans , Cell Line , HL-60 Cells , Leukemia , Leukocytes, Mononuclear , Metabolism , Macrophage Colony-Stimulating Factor , Metabolism , Receptor, Macrophage Colony-Stimulating Factor , Tumor Cells, CulturedABSTRACT
Objective To study the effect of caveolin-1 gene expression on the proliferation of human gastric adenocarcinoma cells,and to explore the possibility for its future usage in gene therapy.Methods The full-length caveolin-1 gene was stably transfected into the MGC803 cell line by lipofectin.The Pcl neo vector was transfected at the same time as mock control.The expression of caveolin-1 was detected by Western blot in both the caveolin-1 gene transfected MGC803 cells and the controls.The cell cycle was analyzed by flow cytometry.Results After transfected with caveolin-1,MGC803 cells significantly up-regulated the expression of caveolin 1 and extended their doubling time.The cell proliferation was inhibited and the cell cycle was arrested in the G_0/G_1 phase.Conclusion Caveolin-1 can inhibit the proliferation of MGC803 cells and induce cell cycle arrest in G_0/G_1 phase.
ABSTRACT
AIM:To explore the production and cytotoxicity of the reactive oxygen species(ROS)induced by diallyl trisulfide(DATS)in HL-60 cells.METHODS:HL-60 cells were either treated with various doses of DATS alone,or DATS combination with apocynin,a specific NADPH oxidase inhibitor,or with antioxidant N-acetyl-L-cysteine(NAC)for 0,1,3,6,12 and 24 h,respectively.The intracellular ROS level was measured by flow cytometry.The activity of NADPH oxidase was evaluated by NBT reduction experiment.The content of both malondialdehyde(MDA)and the protein carbonyl were analyzed by spectrophotometer.RESULTS:The results from flow cytometry indicated that DATS significantly increased the intracellular ROS level in HL-60 cells(P