Sodium arsenite selectively inducing apoptosis of G2+M phase NB4 cells

Objective To explore the mechanism of sodium arsenite inducing apoptosis of NB4 cells. Methods The apoptosis of NB4 cells was studied by flow cytometry, DNA gel electrophoresis and Western blot analysis. Results Sodium arsenite induced apoptosis of NB4 cells while the cells were arrested in G2+M phase; dUTPFITC specifically labeled NB4 cells in G2+M phase after the cells were treated with sodium arsenite; After the treatment the expressions of cyclin A, E,D1,D2 and D3 of the NB4 cells did not change significantly, while the expression of cyclin B1 was upregulated with prolongation of the treatment; Some of S phase NB4 cells expressed high level cyclin B1 during the early period of treatment (16h), but most of NB4 cells expressing high level of cyclin B1 were in G2+M phase. ConclusionTBZSodium arsenite selectively induced apoptosis of G2+M phase NB4 cells, accompanied by upregulation of cyclin B1.