Table 4.
In vitro mammalian chromosome aberration test conducted with GT
| Concentration (µg TOS/ml) | Relative cell growth (%) | Number of cells with structural aberrations | Number of cells with aberrations—gap (%) | Number of polyploid cells (%) | |||||
|---|---|---|---|---|---|---|---|---|---|
| Gap | ctb | cte | csb | cse | Others | ||||
| 6‐hr short‐term treatment: −S9 | |||||||||
| Negative control (100 µl/ml distilled water) | 100.0 | 0 | 2 | 0 | 0 | 0 | 0 | 2 (0.7)* | 1 (0.3) |
| 1,000 | 92.4 | 1 | 7 | 1 | 0 | 0 | 0 | 8 (2.7) | 1 (0.3) |
| 3,000 | 79.8 | 4 | 8 | 7 | 0 | 0 | 0 | 15 (5.0)** | 2 (0.7) |
| 4,000 | 72.8 | 1 | 11 | 3 | 0 | 0 | 0 | 14 (4.7)** | 1 (0.3) |
| 5,000 | 60.3a | – | – | – | – | – | – | – | – |
| Positive control (0.1 µg/ml MMC) | 79.0 | 10 | 87 | 130 | 0 | 0 | 0 | 172 (57.3)** | 1 (0.3) |
| 6‐hr short‐term treatment: +S9 | |||||||||
| Negative control (100 µl/ml distilled water) | 100.0 | 1 | 1 | 0 | 0 | 0 | 0 | 1 (0.3)* | 0 (0.0) |
| 500 | 97.4 | 0 | 2 | 6 | 0 | 0 | 0 | 8 (2.7)** | 0 (0.0) |
| 1,000 | 76.1 | 1 | 13 | 10 | 1 | 0 | 0 | 23 (7.7)** | 0 (0.0) |
| 2,000 | 63.3 | – | – | – | – | – | – | – | – |
| 3,000 | 71.5 | 1 | 26 | 11 | 0 | 0 | 0 | 35 (11.7)** | 0 (0.0) |
| 4,000 | 76.6a | – | – | – | – | – | – | – | – |
| Positive control (12.5 µg/ml CP) | 45.3 | 3 | 76 | 196 | 0 | 0 | 0 | 214 (71.3)** | 2 (0.7) |
| 24‐hr continuous treatment | |||||||||
| Negative control (100 µl/ml distilled water) | 100.0 | 1 | 1 | 1 | 0 | 0 | 0 | 2 (0.7)* | 1 (0.3) |
| 500 | 86.6 | 2 | 19 | 4 | 0 | 0 | 0 | 22 (7.3)** | 2 (0.7) |
| 1,000 | 96.9 | 7 | 32 | 7 | 0 | 0 | 0 | 39 (13.0)** | 1 (0.3) |
| 3,000 | 78.0 | 9 | 44 | 16 | 0 | 0 | 0 | 59 (19.7)** | 3 (1.0) |
| 4,000 | 55.8 | – | – | – | – | – | – | – | – |
| Positive control (0.05 µg/ml MMC) | 64.7 | 6 | 66 | 80 | 0 | 0 | 0 | 129 (43.0)** | 0 (0.0) |
Abbreviations: ‐gap, total number of cells with aberrations except gap; –, not applicable; −S9, in the absence of S9; +S9, in the presence of S9; CP, cyclophosphamide; csb, chromosome break; cse, chromosome exchange; ctb, chromatid break; cte, chromatid exchange; GT, glutaminase from nongenetically modified A. niger strain GT147; MMC, mitomycin C; TOS, total organic solids.
a
There were a lot of c‐mitosis figures, and almost none of the analyzable mitosis were observed.
*
Significant correlation with dosage levels (Cochran‐Armitage trend test): p ≤ .025.
**
Significant difference from control (Fisher's exact test): p ≤ .025.