Table 1.
Triterpenoids (CDDO-Im and CDDO-Me) reduce the total burden and severity of lung tumors whereas DMF increases the number and severity of lung tumors in A/J mice injected with vinyl carbamate.
| Treatment (diet in mg/kg) | Control | CDDO-Im | CDDO-Me | DMF | |||||
|---|---|---|---|---|---|---|---|---|---|
| 50 | 100 | 200 | 12.5 | 50 | 400 | 800 | 1200 | ||
| Tumor number, size, burden | |||||||||
| n | 104 | 24 | 24 | 24 | 24 | 24 | 44 | 48 | 24 |
| Average number of tumors (% control) | 3.21±0.15 (100) | 2.54±0.34 (79) | 3±0.49 (94) | 2.17±0.29*(68) | 2.17±0.27* (68) | 2.13±0.24* (66) | 4.09±0.25* (127) | 3.25±0.25 (101) | 4.13±0.44* (129) |
| Average tumor size, mm3 (% control) | 0.37±0.04 (100) | 0.16±0.02* (43) | 0.16±0.02* (43) | 0.05±0.008*(14) | 0.09±0.01* (24) | 0.037±0.007* (11) | 0.25±0.02 (68) | 0.25±0.02 (68) | 0.23±0.03* (62) |
| Average tumor burden, mm3 (% control) | 1.19±0.14 (100) | 0.39±0.07* (33) | 0.49±0.11* (41) | 0.12±0.02*(10) | 0.2±0.03* (17) | 0.08±0.02* (7) | 1.02±0.08 (86) | 0.82±0.09 (69) | 0.95±0.17 (80) |
| Tumor histopathology | |||||||||
| Number of tumors | 334 | 61 | 73 | 52 | 52 | 51 | 180 | 156 | 99 |
| Total number of medium-grade tumors (% total) | 134 (40) | 27 (44) | 36 (49) | 30* (58) | 26 (50) | 26 (51) | 61 (34) | 53 (34) | 34 (34) |
| Total number of high-grade tumors (% total) | 172 (52) | 27 (44) | 26* (36) | 11* (21) | 16* (31) | 7** (14) | 110* (61) | 98* (63) | 59 (60) |
Female mice were injected i. p. with two doses of vinyl carbamate (0.32mg per mouse) 1 week apart and fed with control, CDDO-Im (50, 100 and 200mg/kg), CDDO-Me (12.5 and 50mg/kg) or DMF (400, 800 and 1200mg/kg) diets, beginning 1 week after the last injection of carcinogen, for 15 weeks. Number, size of tumors and histopathology of tumors were evaluated by two independent investigators. Values represent mean ± standard error.
*P < 0.05, **P < 0.001.