Figure 3

The disruption of microtubules, which was induced by selenite, caused cell cycle arrest in HL60 cells. (A) An alteration in the cell cycle distribution was detected by flow cytometry after cells were exposed to 20 μM of selenite for varying times. The experiment was repeated three times, the mean value was exhibited, and *P < 0.05, when compared to untreated cells. (B) Cells treated with sodium selenite (20 μM) showed increased levels of Cyclin B1 and decreased levels of Mcl-1 in a time-dependent manner. After cells were exposed to selenite (20 μM) for varying times, they were collected, and alterations in Cyclin B1 and Mcl-1 levels were detected by western blotting. This experiment was repeated at least 3 times. (C) Taxol reversed the change in Cyclin B1 and Mcl-1 levels. Cells were pretreated with Taxol (20 nM) for 1 h before being exposed to 20 μM sodium selenite. The cells were harvested and alterations in Cyclin B1 and Mcl-1 levels were detected by western blotting. This experiment was repeated at least 3 times. (D) The disruption of microtubule reorganization caused down-regulation of Mcl-1 and up-regulation of Cyclin B1 in Jurkat cells. Colchicines (20 nM or 50 nM) were added to cells after selenite exposure at 2 h. After the cells were treated with selenite (20 μM) for 24 h, they were harvested, and alterations in Cyclin B1 and Mcl-1 levels were detected by western blotting. This experiment was repeated at least 3 times.