[Deferoxamine induces apoptosis of K562 cells].

Objective: To study the molecular mechanism of apoptosis of leukemic cells (K562 cells) induced by iron chelating agent deferoxamine (DFO).

Methods: The exponentially growing K562 cells were used (1×10(6)/mL) in this study. The K562 cells were treated with different concentrations of DFO (10, 50 and 100 mmol/L), DFO+FeCl3 (10 μmol/L each) or normal saline (blank control).

[Valproic acid induced intracellular GSH-redox imbalance and apoptosis of leukemic cells resistant to dexamethasone and doxorubicin].

Objective: To investigate the anti-neoplastic effects of Valproic acid (VPA) on leukemic cells, especially drug-resistant lines, and to investigate whether modulation of GSH-redox status is involved in VPA-induced apoptosis.

Methods: After the treatment of VPA at various concentrations for indicated times, cellular proliferation of the Jurkat, CEM, HL-60, K562, K562/AO2 cells were evaluated via MTT assay; and the activities of Caspase-3, Caspase-8 and Caspase-9 were quantitatively analyzed by colorimetric assay. The morphological change and cell cycle distribution were also examined on Jurkat (Dexamethasone-resistant) and K562/AO2 (Doxorubicin-resistant) cell lines.

[Expression of HSP70 mRNA and MDR1 mRNA in K562 cells induced by heat shock and ADM].

This study was purpose to investigate the expression levels of HSP70 and MDR1 genes under heat shock and/or adriamycin (ADM) chemotherapy stimulation. The K562 cells were bathed in water at 43 degrees C for 1 hour, then the heat-treated K562 cells were collected and were cultured at 37 degrees C. The expression of HSP70 was assayed by immunocytochemistry, the growth suppression rate of K562 cells was detected by MTT assay, the function of P-gp and the expressions of HSP70 mRNA, MDR1 mRNA were detected by flow cytometry and real-time quantitative PCR (RT-PCR) respectively.

[Detection of the labile iron pool in leukemia cells and its significance].

To explore a rapid and easy method to detect labile iron of pool (LIP) in cells, HL-60 and K562 cells were cultured at a concentration 1 x 10(6)/ml in RPMI 1640 containing 10% heat-inactivated fetal bovine serum. The iron deprivation was induced by adding desferrioxamine (DFO) 10 - 100 micromol/L for 0 - 48 hours. The intracellular LIP was measured by probe calcein-AM.

[Prevalence of iron deficiency in children aged 7 months to 7 years in China].

Objective: To collect epidemiological data of iron deficiency in Chinese children 7 months to 7 years of age, so more rational strategies of prevention and treatment against iron deficiency can be made.

Methods: All the 31 provinces, municipalities and autonomous regions in China were first divided into 3 major regions based on geographic location socioeconomic developmental status. Among them, 15 provinces, municipalities and autonomous regions were randomly selected: 6 from the coastal regions, 5 from inland regions and 4 from remote regions.

[Prevalence of iron deficiency in pregnant and premenopausal women in China: a nationwide epidemiological survey].

Objective: In order to better understand the iron status in pregnant and premenopausal nonpregnant women in China.

Methods: A nationwide epidemiological survey was undertaken in the year 2000 to investigate the prevalence rates (PR) of iron depletion (ID), iron deficiency anemia (IDA) and iron deficiency (ID + IDA). 3591 pregnant women and 3721 premenopausal women were selected by multi-stratification and random sampling from 26 cities and counties of 15 provinces.

[Expression of MOST-1 mRNA in bone marrow mononuclear cells from patients with acute lymphoblastic leukemia].

Objective: To investigate the MOST-1 mRNA expression in bone marrow (BM) mononuclear cells in children with acute lymphoblastic leukemia, and to explore its association with immunophenotype and treatment response.

Methods: Semiquantitative RT-PCR was employed to study the MOST-1 mRNA expression in BM mononuclear cells separated by Ficoll density gradient method. The MOST-1 expression levels were represented by the ratio of MOST-1 band pixels against its corresponding housekeeping gene beta-actin mRNA band pixels determined by GDS8000 densitometry and GelWork-1 analysis software.

[EGR-1 mRNA expression during 12-0-tetradecanoylphorbol-13-acetate-induced K562 cell differentiation].

Objective: 12-0-tetradecanoylphorbol-13 acetate (TPA) plays an important role in precipitating cell differentiation for various tumor cells, especially leukemic cells. Changes of many genes may be involved in this process. The purpose of this study was to observe the relationship between the EGR1mRNA expression and cell differentiation during TPA-induced K562 cell differentiation.

[Erythropoietin increases transferrin receptor expression and the impact of erythropoietin on K562 leukemic cell cycle].

Objective: Functionally, erythropoietin (EPO) can promote the proliferation and growth of erythroid progenitor cells, and it is widely used in the treatment of anemia in chronic diseases caused by tumor and inflammation. However, it is unclear whether EPO has any effect on tumor cell iron metabolism and tumor cell proliferation. The purpose of this study was to explore the effects of recombinant human EPO (rhEPO) on the expression of transferrin receptor (TfR, CD(71) antigen) of leukemic cell K562 and its relation to cell cycle.

[Effect of nitric oxide on iron metabolism in rats with anemia of chronic disease].

To explore the role of nitric oxide (NO) in the pathogenesis and effect on regulation of iron metabolism in anemia of chronic disease (ACD) and provide experimental evidence for prevention and treatment of ACD. On the basis of traditional animal model of rheumatoid arthritis, an ACD rat model was established by repeated injection of Freund's complete adjuvant. The relationship between NO concentration and iron metabolism was observed in ACD rats with and without NO synthase inhibitor, L-NAME, (N omega-nitro-L-arginine methyl ester L-NAME).

[Effect of T3 on the expression of transferrin receptor and ferritin in K562 cells and its possible mechanism].

Objective: To explore the effect of T(3) on the expression of transferrin receptor (TfR) and ferritin (Fn) in K562 cells and its possible mechanism.

Methods: Flow cytometry was used for the detection of TfR expression, radioimmunoassay for Fn expression, RNA/protein band shift assay for the binding activity of iron regulatory protein (IRP) and iron responsive elements (IRE), and RT-PCR for TfR and Fn mRNA levels.

Results: Different concentration of T(3) significantly increased Fn expression of K562 cells, especially at 100 nmol/L and 200 nmol/L (p < 0.