Figure 4. X-ray causes a transient G₂/M arrest in HMEC cell cycle. (A) HMEC cells grown to 50–60% confluency were exposed to either 30 kVp/0.1 Gy or 80 kVp/2.5 Gy X-ray, cells were harvested at the indicated time-points post-irradiation, and the cell cycle analysis was performed using a BD FACSCanto II Flow Cytometer. (B) G₂/M phase cells were statistically analyzed and presented as percentages.