Table 2.
Tumor | 4-1-ST
|
AZ-521
|
SC-2
|
|||
---|---|---|---|---|---|---|
Enzyme | Control | Irinotecan (75 mg/kg/wk × 2) | Control | Irinotecan (75 mg/kg/wk × 2) | Control | Irinotecan (75 mg/kg/wk × 2) |
TS | 2.163±0.281 | 1.375±0.184* | 0.622±0.095 | 0.082±0.019* | 0.089±0.043 | 0.086±0.033 |
DPD | 2.22 ± 0.27 | 1.84 ± 0.34 | 78.10±12.59 | 53.87±15.40† | 8.580±3.45 | 8.120±1.46 |
OPRT | 8.119±0.663 | 7.599±0.806 | 6.649±0.772 | 4.726±0.600† | 21.01±2.68 | 22.10±4.00 |
TP | 1.011±0.018 | 1.168±0.157 | 0.115±0.030 | 0.103±0.025 | 0.647±0.154 | 0.676±0.105 |
RNR | 2.030±0.975 | 3.076±1.183 | 0.483±0.282 | 0.660±0.099 | 4.330±1.840 | 4.150±0.730 |
TK | 15.28±1.90 | 15.29± 3.41 | 31.10± 3.75 | 35.97± 6.86 | 32.01± 4.20 | 68.70±13.61 |
For each tumor, mice received saline (n=5) or irinotecan 75 mg/kg (n=5) administered IV weekly for 2 weeks. At 24 hours after last treatment, tumors were removed and activities of 5-FU-metabolizing enzymes were measured. TS = thymidylate synthase; DPD = dihydropyrimidine dehydrogenase; OPRT = orotate phosphoribosyltransferase; TP = thymidine phosphorylase; RNR = ribonucleotide reductase; TK = thymidine kinase.
P < .01
P < .05 compared with control group by Dunnett’s test