[Relationship between drug resistance and the expression of NF-kappaB induced in leukemic cells].

Autor: Zhang XH; The Second Affiliated Hospital, College of Medicine, Zhejiang University, Hangzhou 310009, China., Su LD, Lu QH, Liang Y, Zhao XY
Jazyk: čínština
Zdroj: Zhejiang da xue xue bao. Yi xue ban = Journal of Zhejiang University. Medical sciences [Zhejiang Da Xue Xue Bao Yi Xue Ban] 2004 Sep; Vol. 33 (5), pp. 421-6.
DOI: 10.3785/j.issn.1008-9292.2004.05.011
Abstrakt: Objective: To explore the relationship between drug resistance of leukemic cells and the expression of both IkappaB-alpha and NF-kappaB associated with apoptosis induced by arsenic trioxide (As2O3) in K562 and K562/ADR cells.
Methods: Apoptosis was induced in K562 and K562/ADR cells cultured with As2O3 in different concentrations. Western blot was used to analyze the expression of NF-kappaB in nuclear and IkappaB-alpha in cytoplasm of these cells. Apoptosis and degradation of IkappaB-alpha protein were also observed by flow cytometry.
Results: After exposure to As2O3, the ratio of apoptosis cells in K562/ADR was significantly lower than that in K562 cells. K562/ADR [(6.33+/-1.51)%] and K562 cells [(13.25+/-1.83)%] cultured with 1 micromol/L As2O3 were in apoptosis. When cultured with 4 micromol/L As2O3, the apoptosis cells increased to (8.00+/-1.47)% and (50.56+/-8.62)%, respectively. The level of IkappaB-alpha in K562 cytoplasm was down-regulated from 88.07% to 49.21% after As2O3 stimulation, while NF-kappaB in nuclear was up-regulated, that was not found in K562/ADR cells.
Conclusion: As2O3 could induce apoptosis of K562 cells, associated with the degradation of IkappaB-alpha and the activation of NF-kappaB. There are an elevated expression of NF-kappaB and resistance to apoptosis induced by As2O3 in K562/ADR cells.
Databáze: MEDLINE