ABSTRACT
Objective To investigate the effect of decitabine (DAC) on human acute myeloid leukemia (AML) cell line HL-60 and the regulating of natural killer (NK) cell activating receptor (NKG2D) ligands(NKG2DL), and to detect the molecular mechanism of JAK-STAT3-SOCS signaling pathway. Methods The effect of DAC on the proliferation of HL-60 was detected by using CCK-8 assay. The cell apoptosis was analyzed by using Annexin-V/PI double standard method. The expressions of receptor NKG2DL including MICA/B and ULBPs in HL-60 cells were detected by using flow cytometry (FCM). The killing activity of NK cells was analyzed by using carboxy fluorescein diacetate succinimidyl ester (CFSE). The expressions of JAK/STAT3 signaling pathway or molecules including STAT3, its upstream kinases JAK1, JAK2 and the negative regulator of STAT3,SOCS-1,SOCS-3 were examined by Western blot.Methylation level of the SOCS-1,SOCS-3 gene after the treatment of DAC was analyzed by using methylation-sensitive high resolution melting(MS-HRM). Results There was an obvious inhibitory effect of DAC on HL-60 cells. The cell viability of HL-60 treated with 0.2, 0.5, and 1.0 μmol/L DAC for 48 h was decreased by (25±11) %, (39±8) % and (50±7)%(P<0.01)respectively compared with those cells without DAC treatment.The incidence of apoptosis was (24.77±7.50) %, (27.10±4.48) % and (30.53±3.93) % after DAC treatment for 48h respectively, which were higher than that of untreated cells[(3.11±0.50)%](P<0.01).DAC induced a significant up-regulation of MICA/B, ULBP-1, ULBP-3 in HL-60 cells, and enhanced the sensitivity of HL-60 cells to NK cytotoxicity. Western blot results showed that a down-regulating expression of STAT3 and JAK1, JAK2 protein was detected, in addition to the phosphor-STAT3 and phosphor-JAKs in HL-60 cells after DAC treatment, but the expressions of SOCS-1 and SOCS-3 protein were increased. HRM results showed that DAC could inhibit the methylation of SOCS-3 gene. Conclusion DAC can inhibit the proliferation of HL-60 cells, upregulate the expression of NKG2DL and enhance the cytotoxicity of NK targeted to HL-60 cells, which might be related to the activity regulation of intracellular JAK-STAT3-SOCS signaling pathway.
ABSTRACT
Objective To investigate the effect of decitabine (DAC) on human acute myeloid leukemia (AML) cell line HL-60 and the regulating of natural killer (NK) cell activating receptor (NKG2D) ligands(NKG2DL), and to detect the molecular mechanism of JAK-STAT3-SOCS signaling pathway. Methods The effect of DAC on the proliferation of HL-60 was detected by using CCK-8 assay. The cell apoptosis was analyzed by using Annexin-V/PI double standard method. The expressions of receptor NKG2DL including MICA/B and ULBPs in HL-60 cells were detected by using flow cytometry (FCM). The killing activity of NK cells was analyzed by using carboxy fluorescein diacetate succinimidyl ester (CFSE). The expressions of JAK/STAT3 signaling pathway or molecules including STAT3, its upstream kinases JAK1, JAK2 and the negative regulator of STAT3,SOCS-1,SOCS-3 were examined by Western blot.Methylation level of the SOCS-1,SOCS-3 gene after the treatment of DAC was analyzed by using methylation-sensitive high resolution melting(MS-HRM). Results There was an obvious inhibitory effect of DAC on HL-60 cells. The cell viability of HL-60 treated with 0.2, 0.5, and 1.0 μmol/L DAC for 48 h was decreased by (25±11) %, (39±8) % and (50±7)%(P<0.01)respectively compared with those cells without DAC treatment.The incidence of apoptosis was (24.77±7.50) %, (27.10±4.48) % and (30.53±3.93) % after DAC treatment for 48h respectively, which were higher than that of untreated cells[(3.11±0.50)%](P<0.01).DAC induced a significant up-regulation of MICA/B, ULBP-1, ULBP-3 in HL-60 cells, and enhanced the sensitivity of HL-60 cells to NK cytotoxicity. Western blot results showed that a down-regulating expression of STAT3 and JAK1, JAK2 protein was detected, in addition to the phosphor-STAT3 and phosphor-JAKs in HL-60 cells after DAC treatment, but the expressions of SOCS-1 and SOCS-3 protein were increased. HRM results showed that DAC could inhibit the methylation of SOCS-3 gene. Conclusion DAC can inhibit the proliferation of HL-60 cells, upregulate the expression of NKG2DL and enhance the cytotoxicity of NK targeted to HL-60 cells, which might be related to the activity regulation of intracellular JAK-STAT3-SOCS signaling pathway.
ABSTRACT
OBJECTIVE To analyze the pathogenic distribution and antimicrobial resistance in our hospital in 2006 and provide the rational information to use antibiotics reasonably.METHODS Flora cultivation and isolation were operated with the methods described by the National Clinical Laboratory Operational Regulations.Flora was identified with the VITEK32 automatic identifier,and bacteria-susceptibility test was operated with Kirby-Bauer method.RESULTS Totally 967 strains of pathogenic bacteria were isolated;they comprised 326 strains of Gram-positive bacteria,541 strains of Gram-negative bacteria and 100 strains of fungi.The main Gram-positive microorganisms included Staphylococcus aureus and Enterococcus faecalis,et al.The main Gram-negative microorganisms included Escherichia coli,Klebsiella pneumoniae,Acinetobacter baumannii,Stenotrophomonas maltophilia and Pseudomonas aerugiinosa,et al.Specimen samples mainly isolated from sputum(43.85%),urine(22.34%),and secretion(10.03%).G+ microorganisms were sensitive to nitrofurantoin and vancomycin.G-microorganisms except A.baumannii and S.maltophilia were sensitive to cefoxitin,piperacillin/tazobactam,imipenem,and amikacin;the average resistant rates of A.baumannii and S.maltophilia to antibiotics were 68.20% and 64.43%,respectively.CONCLUSIONS The severe degree of bacterial multi-drug resistance is increasing,it is urgent to carry out surveillance of bacterial resistance for reasonabe use of antibiotics and decreasing the morbidity rate and the fatality rate.
ABSTRACT
0.05).Conclusions Compared with the patients with Chronic Hepatitis C related to transfusionem,the efficiency of peg-IFN alpha-2b combined with ribavirin in treatment of IVDU with Chronic Hepatitis C was similar,and the therapy is a effective choice in treatment of IVDU with Chronic Hepatitis C.