Figure 2.

Induction of cell-cycle arrest by CPT or CN-CPT treatment. CAL-62 (A, B) and BHT-101 (C, D) cells (1.5 × 10⁵) were treated or not with CPT or CN-CPT (10⁻⁸ and 10⁻⁹ M) for 48 h and cell cycle was then assessed by flow cytometry. CPT and CN-CPT were replenished every 24 h (48 h culture: 24 + 24 h) without changing the culture medium. Graphs show: (A, C) the % of cells in each cycle phase detected in one representative experiment, (B, D) the % of cells in S phase cycle expressed as means ± SEM (n = 3). Each experiment was performed in triplicate. §§p < 0.01, significantly different from untreated cells; *p < 0.05, **p < 0.01, significantly different from treated cells at the same drug concentration.