Effect of STAT 5 decoy oligodeoxynudeotide on tumorigenicity of K 562 cells in nude mice / 肿瘤

Objective: As a potential gene therapeutic method, transcription factor decoy strategy has been used to block the transcription function of multi-transcription factors. This study aims to further verify the inhibitory effect of signal transducer and activator of transcription 5 (STAT 5) decoy oligodeoxynucleotides (ODN) on tumor growth in nude mice. Methods: The xenografted tumor model was established by subcutaneously injecting leukemia K 562 cells in nude mice. Liposome-ODN complex was directly injected into tumor body once daily every 3 days. The tumor growth and tumor size were measured everyday. Nude mice were sacrificed at the end of the experiment. The tumor was removed and weighed. RT-PCR and Western blotting were performed to detect mRNA and protein expression of bcl-xL, cyclin D1, and c-myc, respectively. Results: The tumorigenicity of K 562 cells was significantly inhibited by decoy ODN. The tumor weight was markedly reduced in decoy ODN group than mutant ODN group [(0.485 ± 0.178) g vs (0.928 ± 0.223) g, P < 0.05 ]. The tumor growth inhibition rate was 47.7%. RT-PCR and Western blotting showed that the mRNA and protein expression level of bcl-xL, cyclinD1, and c-myc were down-regulated. Conclusion: Transcription factor decoy strategy effectively blocks transcription of STAT 5 target genes in xenografted tumor of nude mice.

Demonstration of carbonic anhydrase Ⅲ for 25 000 protein decreased in skeletal muscle of myasthenia gravis / 中华神经科杂志

Objective To demonstrate the carbonic anhydrase Ⅲ (CAⅢ) for 25 000 protein decreased in skeletal muscle of myasthenia gravis (MG). Methods The protein molecular properties responsible to antibodies against 25 000 protein and CAⅢ were analyzed by a combination method of two-dimensional electrophoresis and immuno-Western blot. Competitive binding reactions of the antibodies to the purified 25 000 protein and muscular homogenate were observed by using immuno-Dot blot and immuno-Western blot, respectively. The expression of CAⅢ from normal and MG muscles was detected by immuno-Western blot. Results Combination analysis of two-dimensional electrophoresis and immuno-Western blot showed that the protein of immunological responsible to antibodies against 25 000 protein and CAⅢ had an identical molecular mass and isoelectric point. Competitive binding reactions proved that 25 000 protein and CAⅢ were the same substance, either by immuno-Dot blot or by immuno-Western blot. In addition, a much similar result was obtained when the levels of 25 000 protein from normal and MG muscles were detected by antibodies against 25 000 protein and (CAⅢ) by immuno-Western blot. Conclusion 25 000 protein decreased in the MG skeletal muscle was proved to be just a known protein CAⅢ, which made a basis for further exploring the relationship of CAⅢ deficiency and MG pathogenesis.

The Oxidation Process of Red Blood Cells and the Molecules Involved in their Binding to Macrophage

BACKGROUND AND OBJECTIVES: Controversy exists about the characteristics of the lipid-oxidizing process, and the molecules in oxidized lipids that are involved in the binding and uptake to macrophages, in atherosclerosis. The aim of this study was to find answers to these questions using oxidized red blood cells (ox-RBCs). MATERIALS AND METHODS: The RBCs were oxidized in the presence of various concentrations of CuSO4, and the degree of oxidation evaluated by the semiquantitative measurement of the thiobarbituric acid reactive substance (TBARS). The ox-RBC was characterized using annexin-V and flow cytometry. The relationships between the CuSO4 concentration, the degree of oxidation, characteristics of the ox-RBC and it's binding to macrophages transformed from THP-1 cells, were evaluated. RESULTS: The RBCs were oxidized, not by their gradual changes, but by the sudden transformation of a proportion of the RBCs in relation to the CuSO4 concentration. There were few RBCs between oxidized and non-oxidized groups. The annexin-V bound only to the ox-RBC, with a similar degree of binding in all ox-RBCs. The binding of ox-RBC to macrophages was completely inhibited by oxidized low density lipoprotein, which was directly related to the CuSO4 concentration, the TBARS and the proportion of ox-RBC. CONCLUSION: These results suggest that the oxidation of lipids might be an on-off phenomenon process. Molecules that have the ability to bind annexin-V, presumptively phosphatidyl serine, may be involved in the process of binding the ox-lipids to macrophages. Further study will be needed to clarify these molecules.