Effects of celecoxib combined with arsenic trioxide on bcr-abl protein and signal transduction in CML primary cells / 白血病·淋巴瘤

Objective To explore the effects of celecoxib combined with arsenic trioxide (As2O3) on the mRNA expression,protein expression and protein tyrosine kinase (PTK) activity of bcr-abl fusion gene and its downstream signal transduction in chronic myeloid leukemia (CML) primary cells.Methods The cells were incubated with celecoxib (40 μmol/L) or As2O3 (2 μmol/L) alone and celecoxib (40 μmol/L) combined with As2O3 (2 μmol/L) for 36 hours.The changes of mRNA expression,p210 expression and PTK activity of bcr-abl fusion gene in each group were examined respectively by real time quantitative reverse transcriptase polymerase chain reaction (RQ-RT-PCR),Western blot and PTK activity analysis.The important proteins STAT1,STAT5 and their phosphorylatic proteins p-STAT1 and p-STAT5 and inhibitor of DNA binding 1 (ID1)a common downstream target of oncogenic tyrosine kinase were also analyzed by Western blot.Results The mRNA expressions in control group,celecoxib group,As203 group and celecoxib combined with As2O3 group were (5.97±0.53) ％,(5.74±0.46) ％,(5.94±0.57) ％ and (3.06±0.41) ％ respectively,and the statistical difference was found only between celecoxib combined with As2O3 group and control group (t =28.35,P =0.00).The similar statistic difference was only observed between the two groups from PTK activity tests (t =4.38,P =0.04).Western blot also showed that p210,STAT1,STAT5,p-STAT1,p-STAT5 and ID1 were more extraordinaryly downregulated by celecoxib combined with As2O3 than others treatments.Conclusion Celecoxib combined with As2O3 can downregulate mRNA,p210 expression,PTK activity of bcr-abl fusion gene and inhibit STAT and ID1 signal transduction pathways in a synergistic way.

Allicin enhances cytotoxicity of CPT-11 to colon cancer LoVo cell in vitro / 中国中药杂志

<p><b>OBJECTIVE</b>To study the effect of allicin on human colon cancer cell line LoVo and the combined effect of allicin and CPT-11 on this cancer cell line.</p><p><b>METHOD</b>The LoVo cells were cultured in vitro and treated with allicin in different concentrations. MTT assay was used to test dynamically the cell growth inhibiting effect. Apoptosis induction (Annexin-V-FITC/PI) and modulation of DNA cell cycle were measured by flow cytometry. The change of cytotoxicity of CPT-11 after combination of allicin at the concentration of 4.0, 8.0 mg x L(-1) were investigated.</p><p><b>RESULT</b>Allicin had inhibitive effect on growth of LoVo cells in a dose and time dependent manner, with IC50 value of 32.23, 10.74, 6.58 mg x L(-1) at 24 h, 48 h and 72 h, respectively. The apoptosis rate of LoVo cells increased progressively as the cells were treated with increasing concentration of allicin in 24 h, while the apoptosis rate achieved peak value when the cells were treated with allicin at the concentration of 8 mg x L(-1) in 48 h. The result indicated the low concentrations of allicin (< 4 mg x L(-1)) lead to G2/M cell cycle arrest, and higer concentrations ( > 4 mg x L(-1)) exert G1 + G2/M cell cycle arrest in 24 h. Compared with single use of CPT-11, the combined use of CPT-11 and allicin (4.0, 8.0 mg x L(-1), respectively) showed increasing cytotoxicity on the LoVo cells, with IC50 of 24 h decreasing from 47.5 to 7.4 and 7.2 mg x L(-1), respectively.</p><p><b>CONCLUSION</b>Allicin has significant anti-proliferation effect on human colon cancer cell line LoVo by induction of apoptosis and arrestment of cell cycle and can enhance the cytotoxicity of CPT-11 on the colon cancer LoVo cell.</p>

Detection for expression level of gene FN1,NME2 and TIMP3 in mesenchymal stem cells,tumor cells and leukemia cells / 临床检验杂志

Objective To investigate the differential expression of genes encoding fibronectin 1(FN1),non-metastatic cell proteins 2(NME2) and tissue inhibitor of metalloproteinase 3(TIMP3) in fetal bone marrow mesenchymal stem cells(FMSCs),adult bone marrow mesenchymal stem cells(AMSCs),F6,SGC and leukemia cells and study the molecular biological characters of tumor and leukemia cells.Methods RT-PCR was used to clone the cDNA of total RNA extracted from FMSCs,AMSCs,F6,SGC and leukemia cells respectively and then the expression levels of gene FN1,NME2 and TIMP3 were detected by PCR and real-time PCR.Results The expression levels of gene FN1,NME2 and TIMP3 in AMSCs were higher than those in FMSCs,F6,SGC(P