Résumé
<p><b>OBJECTIVE</b>To explore the effects of As(2)O(3) on BCR-ABL protein level and signal transduction in chronic myeloid leukemia (CML) cells.</p><p><b>METHODS</b>Immunoprecipitation, protein tyrosine kinase (PTK) activity assay, real-time Taqman quantitative PCR and Western blot were used.</p><p><b>RESULTS</b>As(2)O(3) downregulated BCR-ABL protein and STAT1 protein of CML mononuclear cells in the concentrations of 1.0 approximately 2.0 micro mol/L and 0.5 approximately 2.0 micro mol/L after 48 h exposure, respectively. However, p27 protein level was not affected. The PTK activity of BCR-ABL protein was also mildly decreased in CML monouclear cells at 60 h. The bcr-abl mRNA level remained unchanged.</p><p><b>CONCLUSION</b>As(2)O(3) downregulats BCR-ABL protein, STAT1 protein, BCR-ABL signal transduction and PTK activity in CML cells.</p>
Sujets)
Humains , Protéines de fusion bcr-abl , Génétique , Cellules K562 , Leucémie myéloïde chronique BCR-ABL positive , Génétique , Phosphorylation , Protein-tyrosine kinases , Métabolisme , Transduction du signalRésumé
In this research, the effects of two new retinoids, SX-115 and CHU-012, on promyelocytic leukemia cell line NB4 were studied in vitro. Cell proliferation, cell morphologic characters, cell cycle kinetics, reduction ability of NBT, differentiation antigens, immunofluorescence staining and RT-PCR were adopted as the observational parameters. The results showed that SX-115 and CHU-012 induced differentiation of NB4 cells at concentration of 10(-6) mol/L. Comparing the effects of the two retinoids with all trans-retinoic acid (ATRA) at same concentration, there was no significant difference among the three agents. The mechanism of the 2 new retinoids remains possibly the same as ATRA.