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1.
Chinese Journal of Hematology ; (12): 314-319, 2018.
Article in Chinese | WPRIM | ID: wpr-1011753

ABSTRACT

Objective: To investigate whether fusion protein SD-HA could regulate its downstream signaling molecule activity by competing with the phospho-BCR-ABL Y177 site, and its mechanisms to inhibit proliferation and induce apoptosis of K562 cells. Methods: Co-immunoprecipitation interaction technology analysis of fusion protein SD-HA functioned by potently binding to the phospho-BCR-ABL Y177 site, Ras, MAPK and Akt activities were observed in the Ad5F35-SD-HA-treated cells. Western blot analyses of SD-HA fusion protein on cell membrane receptor pathway to death cascade caspase-8, caspase-3 and PRAP were performed. Results: Exploration into the underlying mechanisms revealed that Ad5F35-SD-HA infection functioned by binding to the phospho-BCR-ABL Y177 site, which lead to a complex with Grb2. competitively disrupted the Grb2 SH2-phospho-BCR-ABL Y177 formation. The fusion protein SD-HA could reduce the activation of Ras and phosphorylation of MAPK (p-MAPK) and the expression level of p-ELK, inhibition of Ras-MAPK signaling pathway; SD-HA fusion protein could reduce p-Akt and Akt substrate p-GSK with inhibition of PI3K-Akt signaling pathway, thereby inhibiting the proliferation of K562 cells. Caspases-8-induced apoptosis signal could be activated by DED protein binding to DED domain of precursor caspases-8. Conclusions: The strategy of fusion protein SD-HA inhibiting-Y177 BCR-ABL and Grb2 binding could be used as a novel entry point for the treatment of chronic myeloid leukemia.


Subject(s)
Humans , Adenoviridae , Apoptosis , Cell Proliferation , K562 Cells , Leukemia, Myelogenous, Chronic, BCR-ABL Positive , Oncogene Proteins, Fusion , Phosphatidylinositol 3-Kinases
2.
Chinese Journal of Zoonoses ; (12): 694-699, 2017.
Article in Chinese | WPRIM | ID: wpr-703029

ABSTRACT

The aims of this study are to construct the Bem46 knockout strain of Aspergillus fumigatus,investigate the effect of the Bem46 in the growth and germination,and observe the sensitivity of the oxidative stress,the osmotic stress,the temperature and the response to caspofungin and nikkomycin.The Bem46 gene was identified by sequence alignment in A.fumigatus genome database.The Bem46 knockout strain was construction by the protoplast.The growth was observed and compared between Ku80 and △Bem46 on different culture medium,such as GMM,GMM containing hydrogen peroxide,formamide,sodium chloride and sorbitol.The growth diameter was measured under the different temperatures.The germination rate was observed and compared by microscope.Results showed that the Bem46 gene,Afu7g04660,contained 1 116 bp bases pair and encoding 311 amino acids.Six transformants were obtained by gene cloning and protoplast method and only one was confirmed by PCR and Southernblot.The △Bem46 grew significantly faster than the control strain on the medium containing sorbitol.And there were no visible difference between △Bem46 and Ku80 on the other medium.The germination rate of the △Bem46 was more retarded than the Ku80 in GMM liquid medium.In conclusion,the Bem46 gene plays a role in osmotic stress in A.fumigatus and involved in osmotic pressure induced by sorbitol.And there is no visible effect in oxidative stress.The Bem46 gene has a positive effect on spore germination.

3.
Journal of Southern Medical University ; (12): 226-231, 2016.
Article in Chinese | WPRIM | ID: wpr-273783

ABSTRACT

<p><b>OBJECTIVE</b>To investigate the effects of Sinopodophyllum hexundrum on apoptosis in K562 cells.</p><p><b>METHODS</b>K562 cells were treated with Sinopodophyllum hexundrum at different concentrations and for different lengths of time to determine the optimal conditions of SinoPodophyllum hexandrum treatment for K562 cells using CCK8 assay. The cell apoptotic rate was detected by flow cytometry, and the cell morphology and nuclear morphology of K562 cells were observed with Wright staining and DPAI staining, respectively. The protein expressions of BCR/ABL, p-BCR/ABL, STAT5, p-STAT5 and the apoptosis-related proteins PARP, caspase-3 and cleaved-caspase-3 were determined with Western blotting.</p><p><b>RESULTS</b>The cell proliferation was inhibited in a concentration-and time-dependent manner by 1, 2, and 3 µg/mL Sinopodophyllum hexundrum. The treatment was optimal with a Sinopodophyllum hexundrum concentration of 2 µg/mL a treatment time of 48 h, and the cell apoptotic rate increased in a time-dependent manner and significantly increased at 48 h (P<0.001). The expression of apoptosis-related proteins PARP, caspase-3 and cleaved-caspase-3 were also activated in a time-dependent manner. The cells showed typical apoptotic changes after treatment with 2 µg/mL Sinopodophyllum hexundrum for 48 h with significantly reduced expressions of BCR/ABL, p-BCR/ABL, STAT5, AND p-STAT5.</p><p><b>CONCLUSION</b>Sinopodophyllum hexundrum promotes K562 cell apoptosis possibly by inhibiting BCR/ABL-STAT5 survival signal pathways and activating the mitochondrion-associated apoptotic pathways.</p>


Subject(s)
Humans , Apoptosis , Caspase 3 , Metabolism , Cell Proliferation , Drugs, Chinese Herbal , Pharmacology , Fusion Proteins, bcr-abl , Metabolism , K562 Cells , Mitochondria , Metabolism , STAT5 Transcription Factor , Metabolism , Signal Transduction
4.
Journal of Experimental Hematology ; (6): 976-981, 2015.
Article in Chinese | WPRIM | ID: wpr-357235

ABSTRACT

<p><b>OBJECTIVE</b>To investigate the effect of SH2-Caspase 8 fusion protein expressed by recombinant adenovirus AdE-SH2-Caspase8-HA-GFP (SC) on the apoptosis of K562/G01 cell line, which is a BCR/ABL positive chronic myeloid leukemia cell line and resistant to imatinib.</p><p><b>METHODS</b>The K562/G01 cell line was infected with AdE-SH2-Caspase 8-HA-GFP adenovirus (SC), then the cells were divided into 3 groups: AdE-SH2m-Caspase 8-HA-GFP (SmC) group, AdE-GFP (CMV) group and PBS group as control. The infection efficiency was observed under fluorescent microscopy and by flow cytometry. The expression of fusion protein SH2-Caspase 8-HA was measured by Western blot. The morphology of the cells detected by Wright's staining. The apoptosis of the cells were detected by flow cytometry and DNA ladder. The expression of Caspase 3 and PARP were detected by Western blot.</p><p><b>RESULT</b>The infection efficiency of SC on K562/G01 cells was high which was confirmed by fluorescent microscopy and FCM. SH2-Caspase 8-HA fusion protein were expressed correctly in K562/G01 cells. After treatment with SC the apoptosis of K562/G01 cells could be observed by microscopy. The result of FCM showed that early apoptosis of K562/G01 cells increased significantly as compared with control groups (P < 0.05). DNA ladder showed that the classic DNA ladders appeared in K562/G01 cells after treatment with SC. The wester blot detection showed that the expression level of apoptosis-related protein Caspase 3 and PARP increased.</p><p><b>CONCLUSION</b>The recombinant adenovirus SC expressing SH2-Caspase 8 fusion protein can induces the apoptosis of K562/G01 cells.</p>


Subject(s)
Humans , Adenoviridae , Apoptosis , Caspase 8 , Cell Line, Tumor , Cell Proliferation , Drug Resistance, Neoplasm , Imatinib Mesylate , K562 Cells , Leukemia, Myelogenous, Chronic, BCR-ABL Positive
5.
Journal of Experimental Hematology ; (6): 1517-1522, 2015.
Article in Chinese | WPRIM | ID: wpr-274004

ABSTRACT

Nucleotides have unambiguously emerged as a family of mediators of intercellular communication, which bind a class of plasma membrane receptors, P2 purinergic receptors, to trigger intercellular signaling. P2 receptors can be further divided into two structurally and functionally different sub-famlies, the P2X and P2Y receptors. Different blood cells express diverse spectrum of P2 receptors at different levels. Extracellular adenosine triphosphate (ATP) exerts different effects on blood cells, regulating cell proliferation, differentiation, migration, chemotaxis, release of cytokines or lysosomal constituents, and generation of reactive oxygen or nitrogen species. The relationship between abnormal P2 receptors and human diseases attracts more and more attention. This review briefly discusses the expression and function of P2 receptors in hematopoietic system.


Subject(s)
Humans , Adenosine Triphosphate , Blood Cells , Physiology , Cell Differentiation , Cell Movement , Cell Proliferation , Hematopoiesis , Receptors, Purinergic P2 , Physiology , Signal Transduction
6.
Journal of Experimental Hematology ; (6): 1570-1575, 2015.
Article in Chinese | WPRIM | ID: wpr-272559

ABSTRACT

<p><b>OBJECTIVE</b>To investigate the inhibitory effect of indomethacin combined with imatinib on proliferation of KCL22 and K562/G01 cells, and to elucidate the molecular mechanism of antiproliferative effect by Wnt/β-Catenin signaling way.</p><p><b>METHODS</b>Indomethacin was used in KCL22 and K562/G01 cells. The cell growth was detected by MTT assay to explore the optimal concentration and time. The effect of drugs on proliferation capacity was assessed by MTT assay and colony-forming assay. Flow cytometry was used to identify the cell cycle and apoptosis changes. The protein expression of pβ-catenin (S33/37/T41), pGSK-3β (Ser9) and C-MYC were analyzed by Western blot.</p><p><b>RESULTS</b>The optimal concentration and time of indomethacin on KCL22 and K562/G01 were 80 µmol/L for 48 h. The inhibitory effect of 80 µmol/L indomethacin combined 2 µmol/L imatinib on cell proliferation was significantly better than a single drug treatment. Flow cytometry results showed that cell cycle was arrested in the G0/G1 phase in both combined treatment groups. The number of apoptosis cells in combined treatment groups was significantly higher than that in single drug treatment groups. Compared with the control group or single drug treatment groups, the protein level of pβ-catenin, β-catenin, pGSK-3β (Ser9) and C-MYC decreased significantly.</p><p><b>CONCLUSION</b>Indomethacin significantly enhances inhibitory effect of imatinib on proliferation of KCL22 and K562/G01 cells and regulate cell proliferation through Wnt/β-Catenin signaling way.</p>


Subject(s)
Humans , Apoptosis , Cell Cycle , Cell Line, Tumor , Cell Proliferation , Imatinib Mesylate , Indomethacin , Wnt Signaling Pathway , beta Catenin
7.
Journal of Experimental Hematology ; (6): 623-628, 2014.
Article in Chinese | WPRIM | ID: wpr-349659

ABSTRACT

This study was aimed at exploring the expression pattern of P2X family receptors (P2XR) in peritoneal macrophages and their relationship with the activation states of macrophages in Notch1-induced mouse T-ALL model. After establishment of the leukemia model, F4/80(+) peritoneal macrophages, F4/80(+)CD206(+) M2-like and F4/80(+)CD206(-) M1-like peritoneal macrophages were sorted by flow cytometry based on F4/80 and CD206 surface markers. The expression of P2XR in each cell population was detected by real time RT-PCR. The results showed that macrophages,M1-like and M2-like macrophages moderately expressed P2XR except for P2X5R. The expression of P2XR varied with the development of leukemia. The expression of P2X1R and P2X7R in peritoneal macrophages increased steadily; the expression of P2X2R and P2X3R decreased at late stage of leukemia;the expression of P2X4R slightly decreased at intermediate stage;the expression of P2X6R kept unchanged. At intermediate stage of leukemia, the expression of P2XR in M1-like and M2-like peritoneal macrophages varied. M1-like macrophages expressed higher level of P2X1R than M2-like macrophages, whereas M2-like macrophages expressed higher level of P2X7R than M1-like macrophages, which suggested that the expression of P2XR were related to the activation states. It is concluded that the expression of P2XR in peritoneal macrophages from leukemia mice is related to the progression of leukemia and the activation states of macrophages, which lay a foundation for further studying the role of macrophages in the development of leukemia.


Subject(s)
Animals , Mice , Cytokines , Metabolism , Disease Models, Animal , Macrophages, Peritoneal , Metabolism , Mice, Inbred C57BL , Precursor Cell Lymphoblastic Leukemia-Lymphoma , Metabolism , Receptor, Notch1 , Metabolism , Receptors, Purinergic P2X , Metabolism , Signal Transduction
8.
Journal of Experimental Hematology ; (6): 544-549, 2013.
Article in Chinese | WPRIM | ID: wpr-332739

ABSTRACT

This study aimed to construct the dual expression vectors of wide type or N187D mutant P2X7 receptor and intracellular domain of Notch1 (ICN1) linked by 2A peptide to coexpress them in leukemia cells so as to lay a foundation for further investigating the role of P2X7 in development of leukemia. Overlap PCR was used to construct the dual expression vectors encoding wide type or N187D mutant type P2X7 receptor and ICN1 linked by the self-cleaving 2A sequence. The results showed that stable expressing cell lines were obtained by retroviral infection followed by cell sorting after DNA sequence analysis. RT-PCR, Western blot, intracellular free calcium concentration analysis were used to verify the functionally successful construction of K562 cell line expressing P2X7 receptor alone or with ICN1. DNA sequence analysis revealed that all construction were right. The infection efficiency of packaged constructed virus ranged from 40% to 70% for K562 cells. Stable infected cell line was obtained by cell sorting. RT-PCR analysis revealed that P2X7 receptor and/or ICN1 could be detected at high level in their stable infected cell lines, respectively. Western blot analysis also showed that P2X7 receptor was highly expressed in cell line infected by virus with P2X7 receptor. Sustained increase in intracellular free calcium concentration ([Ca(2+)]i) could be observed in K562 cells overexpressing either type of P2X7 receptor upon stimulation with BzATP. It is concluded that the wide type or N187D mutant P2X7 receptor and ICN1 are simultaneously and functionally over-express in leukemia cells, which lay a foundation for further studying the role of P2X7 receptor in the development of leukemia.


Subject(s)
Humans , Gene Expression , Genetic Vectors , K562 Cells , RNA, Messenger , Genetics , Receptor, Notch1 , Genetics , Receptors, Purinergic P2X7 , Genetics , Retroviridae , Genetics
9.
Chinese Journal of Medical Education Research ; (12): 1321-1323, 2011.
Article in Chinese | WPRIM | ID: wpr-671649

ABSTRACT

ObjectiveTo cultivate students innovative spirit and the ability of studying all their lives independently in the course of clinical transfusion laboratory medicine.MethodsBeginning with examination reform,we adopted the teaching mode,problem situation setting up-guidance to research and cooperation-evaluation of the students' learning effect by use of formative assessment.ResultsNew teaching mode acquired satisfactory results with development of students' activity and creativity.

10.
Journal of Southern Medical University ; (12): 1806-1811, 2011.
Article in Chinese | WPRIM | ID: wpr-333806

ABSTRACT

<p><b>OBJECTIVE</b>To construct a recombinant adenovirus vector for SH2-DED fusion gene and assess its inhibitory effect on the proliferation of K562 cells.</p><p><b>METHODS</b>SH2-DED fusion gene and its mutant SH2mt-DED were amplified by splicing PCR and cloned into pAdTrack-CMV plasmid separately to construct the shuttle plasmids pAdT-SD-EGFP and pAdT-SmD-EGFP, respectively. After Pme I digestion, the shuttle plasmids were transformed into ultra-competent pAd5F35-BJ5183 cells to generate defective adenovirus vectors pAd5F35-SD-EGFP and pAd5F35- SmD-EGFP by homologous recombination. The vectors, linearized by Pac I digestion, were further transfected into AD293 cells for packaging and amplified by infecting AD293 cells repeatedly. K562 cells were then infected by the recombinant adenoviruses and the expression of SD was detected by Western blotting. MTT assay and flow cytometry were used to investigate the effect of Ad5F35-SD-EGFP and Ad5F35-SmD-EGFP on the proliferation of K562 cells.</p><p><b>RESULTS</b>The recombinant adenovirus vectors pAd5F35-SD-EGFP and pAd5F35-SmD-EGFP were constructed correctly, with a titer reaching 1.5×10(12) pfu/ml after amplification. Western blotting demonstrated that the target proteins were effectively expressed in transfected K562 cells. MTT assay and flow cytometry showed that transfection with pAd5F35-SD-EGFP resulted in growth inhibition rate of 55.21% in K562 cells, significantly higher than the inhibition rate of 17.95% following transfection with pAd5F35- SmD-EGFP and 7.33% following PBS treatment (P<0.05).</p><p><b>CONCLUSION</b>The recombinant adenovirus vector Ad5F35-SD-EGFP we constructed can significantly inhibit the proliferation of K562 cells in vitro.</p>


Subject(s)
Humans , Adenoviridae , Genetics , Metabolism , Apoptosis Regulatory Proteins , Genetics , Cell Proliferation , Cloning, Molecular , Genetic Vectors , Green Fluorescent Proteins , Genetics , K562 Cells , Leukemia, Myelogenous, Chronic, BCR-ABL Positive , Pathology , Mutant Proteins , Genetics , Recombinant Fusion Proteins , Genetics , Repressor Proteins , Genetics , Shc Signaling Adaptor Proteins , Genetics , Transfection
11.
Chinese Journal of Epidemiology ; (12): 1043-1046, 2009.
Article in Chinese | WPRIM | ID: wpr-321048

ABSTRACT

Objective To investigate the epidemiological features of patients with nosoeomial invasive fungal infection. Methods Fungi in blood were identified by BaeT ALERT 3D, other clinical samples were cultured by Sabouraud' s dextrose agar (SDA) medium. Candidas were isolated and identified by CHRO Magar candida color medium. Fungus-cultured positive cases from Jan. 2004 to Nov. 2007 were analyzed on items as patients' age, underlying disease, sample, strain, and species distribution. All statistical analyses were carried out by SPSS 13.0. Results The overall incidence rate of invasive fungal infections was 4.12%. The average age of patients was 7-96 with most patients were male, with geriatric problems and different kinds of underlying diseases. Lower respiratory tract infection was the most frequent infection site, followed by urinary tract, gastrointestinal tract. The main pathogens of invasive fungal infections were Candidas (93.80%). Strains of Candida albicans were the most frequent organisms which accounted for 67.29% of all the isolates. Mould fungus infections accounted for only 6.20%. During the 4 years of observation, the detection rate of fungi, specimen sources and the distribution of species and compartment were different with significant differences (P<0.0083). Conduslon The epidemiological properties such as the source of specimen, the distribution of species and composition sections of invasive fungal infections were changing. Candida slaP. were still the main pathogens of invasive fungal infections but the sections of fungi changed. The incidence of Aspergillus infections had been increasing recently.

12.
Chinese Journal of Hematology ; (12): 326-331, 2009.
Article in Chinese | WPRIM | ID: wpr-314482

ABSTRACT

<p><b>OBJECTIVE</b>To observe the effect of recombinant adenovirus-mediated wild-type p53 gene on the number and proteins of centrosome in K562 cells. To explore the possibility of application of wild-type p53 gene therapy in the treatment of chronic myeloid leukemia.</p><p><b>METHODS</b>The recombinant adenoviruses carrying wild-type p53 gene (Ad5 wtp53), mutant p53 gene (Ad5 mtp53) or the green fluorescent protein (GFP) gene was repeatedly amplified and co-infected into K562 cells with cation polybrene. The optimal infection titer and infection time of the recombinant adenoviruses were determined by MTT assay, p53 mRNA and protein expression were determined by RT-PCR and Western blot respectively. The centrosomal structural protein gamma-tubulin and the spindle protein alpha-tubulin were marked simultaneously by indirect immunofluorescence staining, and the expression of the centrosomal gamma-tubulin protein, the mitosis and the number of centrosome were observed under the laser confocal microscopy.</p><p><b>RESULTS</b>Infection efficiency with recombinant adenoviruses was facilitated by polybrene in K562 cells, and 4 microg/ml polybrene was chosen. The optimal adenovirus infection titer was 20,000 MOI and the optimal infection time was 72 hours. p53 mRNA and P53 protein can be expressed in K562 cells by Ad5wtp53 and Ad5mtp53. Both the expression of the centrosomal gamma-tubulin protein and the number of centrosomes were decreased after Ad5wtp53 infection.</p><p><b>CONCLUSION</b>There is sustained expression of P53 protein in K562 cells after its infection by Ad5wtp53. Wild-type P53 protein can lead to the down-regulation of the number of centrosomes and the expression of centrosomal gamma-tubulin protein in K562 cells.</p>


Subject(s)
Humans , Adenoviridae , Genetics , Centrosome , Metabolism , Genes, p53 , Genetics , Genetic Vectors , K562 Cells , Transfection , Tubulin , Metabolism , Tumor Suppressor Protein p53 , Metabolism
13.
Chinese Journal of Hematology ; (12): 34-38, 2008.
Article in Chinese | WPRIM | ID: wpr-262932

ABSTRACT

<p><b>OBJECTIVE</b>To use a decoy RNA targeted blockage of the RNA binding protein E2 (hnRNP E2) resulting in the CCAAT/enhancer-binding protein alpha (C/EBP alpha) gene's abnormal translation and investigate its effect on the granulocytic differentiation of K562 cells and the probable molecular mechanism.</p><p><b>METHODS</b>The hnRNP E2 decoy RNA expression plasmid was constructed and transfected into K562 cells with cationic liposome, and stable expression cells were obtained by G418 selection. The changes of C/EBP alpha and granulocyte colony-stimulating factor receptor (G-CSFR) gene expression were detected by RT-PCR and Western blot. The morphologic changes were observed after Wright-Giemsa staining. The expression of granulocytic differentiation antigens CD13 and CD15 was studied by immunocytochemistry.</p><p><b>RESULTS</b>The stably expressed pG cells were obtained. Its C/EBP alpha mRNA level remained unchanged, while 42kD-C/EBP alpha protein expression was increased by (49.7 +/- 5.5)% (P < 0.05); and G-CSFR mRNA was increased by (42.1 +/- 3.6)% (P < .05), and its protein was increased by (37.4 +/- 6.2)% (P < 0.05) compared to that in the K562 control cells. The characteristics of polymorphonuclear neutrophils appeared in pG cells and CD13 and CD15 positive cell ratios were (18.7 +/- 2.5)% and (26.3 +/- 2.9)% respectively.</p><p><b>CONCLUSIONS</b>HnRNP E2 decoy RNA can induce granulocytic differentiation of K562 cells, and G-CSF promotes this effect. The mechanisms may be that decoy RNA specifically blocks hnRNP E2, hence regulates the translation of C/ EBP alpha mRNA, restores the expression of 42kD-C/EBP alpha, and then up-regulates the expression of G-CSFR gene.</p>


Subject(s)
Humans , CCAAT-Enhancer-Binding Protein-alpha , Genetics , Cell Differentiation , Genetics , Gene Expression Regulation , Heterogeneous-Nuclear Ribonucleoproteins , Genetics , K562 Cells , RNA , Genetics , Translating
14.
Chinese Journal of Hematology ; (12): 724-727, 2004.
Article in Chinese | WPRIM | ID: wpr-229910

ABSTRACT

<p><b>OBJECTIVES</b>To investigate targeted blockage of BCR/ABL oncoprotein mediated cell transformation by STAT5 decoy oligodeoxynucleotide (ODN), its effect on the growth and proliferation inhibition of K562 cells and the related molecular mechanisms.</p><p><b>METHODS</b>STAT5 decoy ODN, designed and synthesized in vitro, was transfected into K562 cells by cationic lipid. The cell growth curve and colony formation assay were used to reflect the growth and proliferation capacity of K562 cells, RT-PCR to detect the expression of three genes downstream STAT5.</p><p><b>RESULTS</b>Confocal microscopy demonstrated that STAT5 decoy ODN was successfully transfected into K562 cells (95.2% positive cells). STAT5 decoy ODN inhibited the growth of K562 cells (inhibition rate 77.7%) and their colony formation capacity (Decoy ODN treated group 8.3% vs control group 35.7%, P < 0.05) after the treatment with STAT5 decoy ODN, the expressions of c-myc, bcl-X(L), cyclin D1 mRNA were down-regulated by 15.4%, 30.8%, 29.1%, respectively in the K562 cells.</p><p><b>CONCLUSIONS</b>STAT5 decoy ODN inhibits the growth and proliferation of K562 cells. The mechanisms may be that decoy ODN blocks the transcriptional activation potent of STAT5 and down-regulates the expression of these tumor related genes downstream STAT5.</p>


Subject(s)
Humans , Cell Proliferation , Cyclin D1 , Genetics , Fusion Proteins, bcr-abl , Genetics , Metabolism , Gene Expression , K562 Cells , Liposomes , Microscopy, Confocal , Oligodeoxyribonucleotides, Antisense , Genetics , Proto-Oncogene Proteins c-myc , Genetics , Reverse Transcriptase Polymerase Chain Reaction , STAT5 Transcription Factor , Genetics , Physiology , Transfection , bcl-X Protein , Genetics
15.
Chinese Journal of Hematology ; (12): 5-7, 2004.
Article in Chinese | WPRIM | ID: wpr-291463

ABSTRACT

<p><b>OBJECTIVE</b>To investigate the effect of small interference RNA (siRNA) on mdr1 and P-glyco-protein (P-gp) expression of multi-drug resistance (MDR) human leukemia cell line K562/A02.</p><p><b>METHODS</b>Three si RNAs (si-mdr1-1, si-mdr1-2, si-mdr1-3) which were specifically targeted mdr1 gene were synthesized and transfected into K562/A02 cells. Expression of mdr1 mRNA was assayed by RT-PCR. P-gp expression and intracellular daunorubicin (DNR) concentration were determined by flow cytometry. 50% inhibition concentration (IC(50)) of doxorubicin (ADM) on K562/A02 was determined by MTT method.</p><p><b>RESULTS</b>Treatment of K562/A02 cell with the 3 kinds of siRNAs resulted in a reversal of MDR of a different extent. The third siRNA was more effective in the suppression of mdr1 with a significant reduction of (58.0 +/- 1.54)% of the mdr1 mRNA expression. Positive expression rate of p170 decreased from (76.0 +/- 1.0)% to (19.6 +/- 1.9)%, and the relative efficiency of K562/A02 to ADM was 70.4%. The intracellular accumulation of DNR increased after siRNA treatment.</p><p><b>CONCLUSION</b>The siRNA could effectively restore the sensitivity of K562/A02 cells to conventional chemotherapeutic agents.</p>


Subject(s)
Humans , Base Sequence , Daunorubicin , Pharmacokinetics , Drug Resistance, Neoplasm , Genes, MDR , Physiology , K562 Cells , Molecular Sequence Data , RNA, Messenger , RNA, Small Interfering , Pharmacology
16.
Chinese Journal of Hematology ; (12): 22-25, 2004.
Article in Chinese | WPRIM | ID: wpr-291459

ABSTRACT

<p><b>OBJECTIVE</b>To explore the effects of vascular endothelial growth factor (VEGF) antisense phosphorothioated oligodeoxynucleotide (AS-ODN) on the expression of VEGF in human leukemic cell lines (HL-60 and K562 cells).</p><p><b>METHODS</b>The levels of VEGF mRNA and protein in leukemic cells incubated with VEGF AS-ODN were measured by RT-PCR, immunohistochemistry assay and ELISA. MTT test was used to examine the influence of the culture supernatant (CS) of VEGF AS-ODN treated leukemic cells on the proliferation of human umbilical vein endothelial cells (ECV304).</p><p><b>RESULTS</b>After leukemic cells were treated with different concentrations (2.5 approximately 15.0 micro mol/L) of VEGF AS-ODN for 24 h, VEGF mRNA level in the cells decreased remarkably in a concentration dependent manner, no change was found in the VEGF missense ODN treated cells (MS-ODN). When the leukemic cells were treated with 5 micro mol/L VEGF AS-ODN for 24 h, VEGF protein level decreased greatly both in the cells and in the CS; and the proliferation stimulating effect of the treated CS on the ECV304 cells reduced. Meanwhile, there was no obvious change in VEGF protein and its effect in the VEGF MS-ODN treated group.</p><p><b>CONCLUSION</b>VEGF AS-ODN could inhibit VEGF expression in human leukemic cell lines in vitro.</p>


Subject(s)
Humans , Enzyme-Linked Immunosorbent Assay , HL-60 Cells , Immunohistochemistry , K562 Cells , Oligonucleotides, Antisense , Pharmacology , RNA, Messenger , Vascular Endothelial Growth Factor A , Genetics
17.
Chinese Journal of Hematology ; (12): 344-346, 2003.
Article in Chinese | WPRIM | ID: wpr-354865

ABSTRACT

<p><b>OBJECTIVE</b>To investigate the effect of MTS1 gene beta promoter transcriptional activation in T-cell acute lymphoblastic leukemia (T-ALL) cell lines and identify the fragment with transcriptional activation.</p><p><b>METHODS</b>Seven pGL3 recombinant plasmids with the same 3'-end transcriptional start site but the different 5'sequences were constructed by gene recombinant technique and transfected into Jurkat cell line which is biallelic deletion of MTS1 gene by transient transfection. Luciferase report gene was detected to observe beta promoter transcriptional activation.</p><p><b>RESULTS</b>Seven pGL3 recombinant plasmids containing different fragments of beta promoter were obtained, all of them showed transcriptional activation in Jurkat cell line. Among them, the 0.38 kb fragment cut by SacII-SacI is fundamental in transcription.</p><p><b>CONCLUSION</b>MTS1 gene beta promoter can be activated in Jurkat cell line.</p>


Subject(s)
Humans , Genes, p16 , Jurkat Cells , Plasmids , Genetics , Promoter Regions, Genetic , Genetics , Transcriptional Activation , Transfection
18.
Chinese Journal of Laboratory Medicine ; (12)2003.
Article in Chinese | WPRIM | ID: wpr-685654

ABSTRACT

Objective To establish a quantitative RT-PCR method with self-quenched fluorogenic probe for detection of bcr/abl mRNA in patients with chronic myeloid leukemia for providing a useful tool for diagnosis of CML,evaluation of therapeutic effect and monitoring of minimal residual disease(MRD). Methods bcr/abl gene from cultured K562 cells was amplified by conventional RT-PCR.The standard quantitative plasmid was constructed by A-T clone method.The self-quenched fluorogenic quantitative RT- PCR method(FQ-RT-PCR)for determination of bcr/abl mRNA was established successfully using the ABI PRISM 7000 PCR Detector.The linear range,sensitivity,stability,and repetitiveness of the method were determined.The marrow samples from 25 CML patients and 3 ALL patients were assessed.Results The sensitivity of the FQ-RT-PCR was 10 copies/?l recombined plasmid,and bcr/abl mRNA can be detected from 1 K562 cell in 10~5 normal cells.The linear range was 10~2-10~9 copies/?l recombined plasmid.The coefficient variation(CV)value was 2.1% in intra-assay and 6.1% in inter-assay.The median ber/abl mRNA expression level was 4.50?10~4 copies/?g RNA [(0.45-89.00)?10~4],5.45?10~4 copies/?g RNA [(2.95-19.30)?10~4 ],13.00?10~4 copies/?g RNA [(4.10-89.00)?10~4] and 2.35?10~4 copies/?g RNA [(0.45-5.12)?10~4] in 25 CML patients,11 patients in the incipient chronic phase,6 patients in blastic crisis,8 patients in chronic period after treatment,respectively.The bcr/abl mRNA level in blastic crisis was significantly higher than that in chronic phase(q= 3.41,P

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