The effect of NCTD on the A549 cells cell cycle progression
Growth inhibition is often associated with cell cycle progression. Therefore, the cycle distribution of A549 cells after exposure to NCTD was measured by propidium iodide staining. As shown in Figure 2A, as the concentration of NCTD treatment increased, cell accumulation in the G2 / M phase increased, with a gradual decrease in the G1 population. The above results indicate that the cell cycle is blocked in the G2 / M phase.
The complex of cyclin and CDKs plays an important role in regulating the progress of the cell cycle, so the expression of cycle-related proteins was further tested by western blot method. After NCTD treatment of cells, the expressions of cyclin D3, E2, G1, and S phases were significantly reduced, while the expression of cyclin B1, cyclin A, and G2 / M phase-related proteins showed an upward trend (Figure 2C). . Moreover, p21 expression was also found to increase, while cdc2 expression was reduced (Figure 2B). The activity of the M phase promoting factor cdc2 / cyclinB complex plays a crucial role in the G2 to M phases. Our results indicate that despite the increased expression of cyclin A and cyclin B1 (G2-phase related proteins), p21 can inhibit the activity of the cdc2 / cyclin B complex. Therefore, we can infer that NCTD induces G2 phase cell cycle arrest by increasing the expression of p21.
fig. 2