Table 1.
Effect of ICR-191 alone, CHL alone, and mixture of ICR and CHL, on level of expression of γH2AX in HL-60 cells
| Cell treatment | All cells | G1 | S | G2M |
|---|---|---|---|---|
| CTRL | 169±2.5 | 112±4.0 | 184±4.5 | 149±4.5 |
| CHL, 1 µM | 159±3.5 | 108±3.5 | 188±1.1 | 226±1.5 |
| ICR 191, 1.2 µM | 190±7.0 | 119±7.1 | 256±12.1 | 248±4.5 |
| ICR 191+CHL, 1 µM | 151±4.5 | 112±6.0 | 179±5.0 | 209±8.2 |
| ICR 191+CHL, 0.5 µM | 164±5.4 | 111±3.8 | 186±4.9 | 231±6.6 |
| ICR 191+CHL, 0.1 µM | 167±4.4 | 119±3.8 | 202±6.1 | 237±3.9 |
The cells were treated with these agents for 1 h and then intensity of γH2AX immunofluorescence concurrently with DNA content was measured in individual cells by flow cytometry as described in Material and methods section. The data show mean values of γH2AX expression (±SD) for all 10,000 cells measured in each sample as well as for cells in G1, S or G2M phases of the cell cycle, identified by the differences in cellular DNA content, as shown in Fig. 5 (left panel) and described in detail elsewhere [36–38]. Note an increase in γH2AX expression predominantly in S-phase cells in cells treated with ICR 191 alone, total elimination of the increase at 1 µM and 0.5 µM of CHL and partial suppression at 0.1 µM CHL. In all samples ICR 191 was present at 1.2 µM concentration.