ToxSci Advance Access originally published online on May 24, 2004
Toxicological Sciences 2004 81(1):26-34; doi:10.1093/toxsci/kfh175
| ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Toxicological Sciences vol. 81 no. 1 © Society of Toxicology 2004; all rights reserved.
Lung Tumorigenicity in A/J and rasH2 Transgenic Mice Following Mainstream Tobacco Smoke Inhalation
Research and Development, R. J. Reynolds Tobacco Co., Winston-Salem, North Carolina 27102
Received March 17, 2004; accepted May 7, 2004
Hypothesizing that their respective genetic backgrounds would confer an increased sensitivity to lung tumorigenesis, the plausibility of selected rodent models for the inhalation testing of mainstream tobacco smoke (MTS) was evaluated. Strain A/J and rasH2 transgenic (Tg) mice were exposed to MTS from Kentucky 1R4F research cigarettes using either a whole-body or nose-only exposure regimen. The whole-body regimen consisted of a 20-week exposure period [0.200 mg wet total particulate matter/liter (WTPM/l), 6 h/day, 5 days/week]; nose-only dosing proceeded for 28 weeks [0.040, 0.125, or 0.400 mg WTPM/l, 3 h/day, 5 days/week]. Both regimens included a 16-week recovery period. Gross and microscopic examinations of the lungs were used to evaluate tumor formation, with experimental results supporting the following conclusions:
- Evaluation of MTS-induced tumorigenicity based on gross evaluation versus microscopic confirmation provides strikingly disparate results, indicating that serial sectioning is necessary for a definitive assessment of lung tumors.
- While the dosing regimens employed do not allow for a definitive comparison, whole-body exposure appeared to be more effective for inducing statistical changes in tumor multiplicity and incidence compared to nose-only exposure.
- Exposure-related stress, evidenced as reductions in both body weight gain and background tumor formation, represents a potential confounder during inhalation testing of MTS tumorigenicity, with additional investigation warranted to validate the specificity of exposure-related responses.
- Comparative findings between A/J and rasH2 Tg mice suggest that the former may be overly sensitive to exposure-related stress, potentially influencing tumorigenic responses.
Key Words: mainstream tobacco smoke; mouse lung tumorigenicity; strain A/J; rasH2 transgenic.
CiteULike 
Connotea 
Del.icio.us What's this?
This article has been cited by other articles:
|
|
 |
|
  F. D'Agostini, L. Mastracci, A. Izzotti, R. Balansky, T. M. Pennisi, V. E. Steele, and S. De Flora Modulation by Phenethyl Isothiocyanate and Budesonide of Molecular and Histopathologic Alterations Induced by Environmental Cigarette Smoke in Mice Cancer Prevention Research, June 1, 2009; 2(6): 546 - 556. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 R. Balansky, G. Ganchev, M. Iltcheva, V. E. Steele, F. D'Agostini, and S. De Flora Potent carcinogenicity of cigarette smoke in mice exposed early in life Carcinogenesis, October 1, 2007; 28(10): 2236 - 2243. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 C. R. E. Coggins An Updated Review of Inhalation Studies with Cigarette Smoke in Laboratory Animals International Journal of Toxicology, July 1, 2007; 26(4): 331 - 338. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
H.-J. Haussmann Smoking and Lung Cancer: Future Research Directions International Journal of Toxicology, July 1, 2007; 26(4): 353 - 364. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
J. A. Hutt, B. R. Vuillemenot, E. B. Barr, M. J. Grimes, F. F. Hahn, C. H. Hobbs, T. H. March, A. P. Gigliotti, S. K. Seilkop, G. L. Finch, et al. Life-span inhalation exposure to mainstream cigarette smoke induces lung cancer in B6C3F1 mice through genetic and epigenetic pathways Carcinogenesis, November 1, 2005; 26(11): 1999 - 2009. [Abstract] [Full Text] [PDF]
|
|