Abstract
We have established a transgenic rat line carrying 3 copies of the human c‐Ha‐ras proto‐oncogene with its own promoter region (Jcl/SD‐TgN(HrasGen)128Ncc) (Hras128 rat), expression being detectable in almost all organs. We have already demonstrated that the rat is highly sensitive to mammary, esophagus and bladder carcinogenesis. In the present study, male and female transgenic and wild‐type littermates were topically treated with 2.5 mg of 7,12‐dimethylbenz[a]anthracene (DMBA) dissolved in 1.0 ml of acetone on the back skin at 50 days after birth. Starting 1 week thereafter, they were again topically treated with 100 nmol of 12‐O‐tetradecanoylphorbol 13‐acetate (TPA) dissolved in 0.5 ml of acetone 3 times weekly for the following 31 weeks. In males treated with DMBA and/or TPA, skin tumors, including both squamous cell papillomas (SCP) and carcinomas (SCC), were preferentially induced at the DMBA‐TPA painting sites: DMBA‐TPA, 15/15 (100%); DMBA, 6/8 (75%); TPA, 1/6 (16.7%). They were also, unexpectedly, induced on remote scrotal skin: DMBA‐TPA, 13/15 (86.7%); DMBA, 5/8 (62.5%); TPA, 0/6 (0%). Lesions were thus more frequent in the DMBA‐TPA group than with DMBA or TPA alone. In females, adenomas and adenocarcinomas of the mammary glands were preferentially induced: DMBA‐TPA, 12/14 (85.7%); DMBA, 6/8 (75%); TPA, 3/6 (50%), with only a few small skin papillomas at painting sites. Incidences and numbers of the mammary and skin tumors were much greater in Hras128 rats than in their wild‐type counterparts. PCR‐RFLP analysis of the transgene indicated that the percentage of the cell populations harboring a mutation in codons 12 and/or 61 ranged from 2% to 60% in individual tumors; skin tumors showed more mutations in codon 61 in the DMBA‐treated groups. In contrast, no mutations were detected in the endogenous rat c‐Ha‐ras gene. These results indicate that the Hras128 rat is highly susceptible to DMBA‐TPA skin and mammary carcinogenesis, thus providing a unique painting model for skin as well as mammary gland carcinogenesis, that would be suitable for investigating the role of transgene mutations.
References
- 1. Ando K, Saitoh A, Hino O, Takahashi R, Kimura M, Katsuki M. Chemically induced forestomach papillomas in transgenic mice carry mutant human c‐Ha‐ras transgenes. Cancer Res 1992; 52: 978–82. [PubMed] [Google Scholar]
- 2. Mitsumori K, Koizumi H, Nomura T, Yamamoto S. Pathological features of spontaneous and induced tumors in transgenic mice carrying a human prototype c‐Ha‐ras gene used for six–month carcinogenicity studies. Toxicol Pathol 1998; 26: 520–31. [DOI] [PubMed] [Google Scholar]
- 3. Doi ST, Kimura M, Katsuki M. Site‐specific mutation of the human c‐Ha‐ras transgene induced by dimethylbenzanthracene causes tissue‐specific tumors in mice. Jpn J Cancer Res 1994; 85: 801–7. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 4. Tsunematsu S, Saito H, Kagawa T, Morizane T, Hata J, Nakamura T, Ishii H, Tsuchiya M, Nomura T, Katsuki M. Hepatic tumors induced by carbon tetrachloride in transgenic mice carrying a human c‐H‐ras proto‐oncogene without mutations. Int J Cancer 1994; 59: 554–9. [DOI] [PubMed] [Google Scholar]
- 5. Yamamoto S, Mitsumori K, Kodama Y, Matsunuma N, Manabe S, Okiyama H, Suzuki H, Fukuda T, Sakamaki Y, Sunaga M, Nomura G, Hioki K, Wakana S, Nomura T, Hayashi Y. Rapid induction of more malignant tumors by various genotoxic carcinogens in transgenic mice harboring a human prototype c‐Ha‐ras gene than in control non‐transgenic mice. Carcinogenesis 1996; 17: 2455–61. [DOI] [PubMed] [Google Scholar]
- 6. Yamamoto S, Urano K, Koizumi H, Wakana S, Hioki K, Mitsumori K, Kurakawa Y, Hayashi Y, Nomura T. Validation of transgenic mice carrying the human prototype c‐Ha‐ras gene as a bioassay model for rapid carcinogenicity testing. Environ Health Perspect 1998; 106 Suppl 1: 56–69. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 7. Tsuda H, Moore MA, Asamoto M, Inoue T, Ito N, Satoh K, Ichihara A, Nakamura T, Amelizad Z, Oesch F. Effect of modifying agents on the phenotypic expression of cytochrome P‐450, glutathione S‐transferase molecular forms, microsomal epoxide hydrolase, glucose‐6‐phosphate dehydrogenase and gamma‐glutamyltranspeptidase in rat liver preneoplastic lesions. Carcinogenesis 1988; 9: 547–54. [DOI] [PubMed] [Google Scholar]
- 8. Tatematsu M, Mera Y, Ito N, Satoh K, Sato K. Relative merits of immunohistochemical demonstrations of placental, A, B and C forms of glutathione S‐transferase and histochemical demonstration of gamma‐glutamyl trans‐ferase as markers of altered foci during liver carcinogenesis in rats. Carcinogenesis 1985; 6: 1621–6. [DOI] [PubMed] [Google Scholar]
- 9. Haas MJ, Sattler CA, Dragan YP, Gast WL, Pitot HC. Multiple polypeptide hormone expression in pancreatic islet cell carcinomas derived from phos‐phoenolpyruvatecarboxykinase‐SV40 T antigen transgenic rats. Pancreas 2000; 20: 206–14. [DOI] [PubMed] [Google Scholar]
- 10. Asamoto M, Hokaiwado N, Cho YM, Shirai T. Effects of genetic background on prostate and taste bud carcinogenesis due to SV40 T antigen expression under probasin gene promoter control. Carcinogenesis 2000; 23: 463–7. [DOI] [PubMed] [Google Scholar]
- 11. Asamoto M, Hokaiwado N, Cho YM, Takahashi S, Ikeda Y, Imaida K, Shirai T. Prostate carcinomas developing in transgenic rats with SV40 T antigen expression under probasin promoter control are strictly androgen dependent. Cancer Res 2001; 61: 4693–700. [PubMed] [Google Scholar]
- 12. Asamoto M, Ochiya T, Toriyama‐Baba H, Ota T, Sekiya T, Terada M, Tsuda H. Transgenic rats carrying human c‐Ha‐ras proto‐oncogenes are highly susceptible to N‐methyl‐N‐nitrosourea mammary carcinogenesis. Carcinogenesis 2000; 21: 243–9. [DOI] [PubMed] [Google Scholar]
- 13. Tsuda H, Asamoto M, Ochiya T, Toriyama‐Baba H, Naito A, Ota T, Sekiya T, Terada M. High susceptibility of transgenic rats carrying the human c‐Ha‐ras proto‐oncogene to chemically‐induced mammary carcinogenesis. Mutat Res 2000; 477: 173–82. [DOI] [PubMed] [Google Scholar]
- 14. Ota T, Asamoto M, Toriyama‐Baba H, Yamamoto F, Matsuoka Y, Ochiya T, Sekiya T, Terada M, Akaza H, Tsuda H. Transgenic rats carrying copies of the human c‐Ha‐ras proto‐oncogene exhibit enhanced susceptibility to N‐bu‐tyl‐N‐(4‐hydroxybutyl)nitrosamine bladder carcinogenesis. Carcinogenesis 2000; 21: 1391–6. [PubMed] [Google Scholar]
- 15. Asamoto M, Toriyama‐Baba H, Ohnishi T, Naito A, Ota T, Ando A, Ochiya T, Tsuda H. Transgenic rats carrying human c‐Ha‐ras proto‐oncogene are highly susceptible to N‐nitrosomethylbenzylamine induction of esophageal tumorigenesis. Jpn J Cancer Res 2002; 93: 744–51. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 16. Han BS, Fukamachi K, Takasuka N, Ohnishi T, Maeda M, Yamasaki T, Tsuda H. Inhibitory effects of 17beta‐estradiol and 4‐n‐octylphenol on 7,12‐dimethylbenz[a]anthracene‐induced mammary tumor development in human c‐Ha‐ras proto‐oncogene transgenic rats. Carcinogenesis 2002; 23: 1209–15. [DOI] [PubMed] [Google Scholar]
- 17. Asamoto M, Ota T, Toriyama‐Baba H, Hokaiwado N, Naito A, Tsuda H. Mammary carcinomas induced in human c‐Ha‐ras proto‐oncogene transgenic rats are estrogen‐independent, but responsive to d‐limonene treatment. Jpn J Cancer Res 2002; 93: 32–35. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 18. Wilson JS, Holland LM. Periodic response difference in mouse epidermis chronically exposed to crude‐oils or BaP: males vs. females. Toxicology 1988; 50: 83–94. [DOI] [PubMed] [Google Scholar]
- 19. Rasmussen KS, Glenthoj A, Arffmann E. Skin carcinogenesis in rats by 3‐methylcholanthrene and 7,12‐dimethylbenz(alpha)anthracene. Influence of dose and frequency on tumour response and its histological type. Acta Pathol Microbiol Immunol ScandA 1983; 91: 445–55. [PubMed] [Google Scholar]
- 20. Schweizer J, Loehrke H, Hesse B, Goerttler K. 7,12‐Dimethylbenz[a]‐anthracene/12‐O‐tetradecanoylphorbol‐13‐acetate‐mediated skin tumor initiation and promotion in male Sprague‐Dawley rats. Carcinogenesis 1982; 3: 785–9. [DOI] [PubMed] [Google Scholar]
- 21. Zackheim HS, Fu KK, Chan AS. Lack of effect of supplemental dietary selenium on time to development of radiation–induced cutaneous tumors in rats. Cancer Lett 1993; 70: 123–7. [DOI] [PubMed] [Google Scholar]
- 22. Zabezhinski MA, Pliss GB, Okulov VB, Petrov AS. Skin tumours induced by local and systemic action of N‐nitroso‐compounds in rats. Arch Geschwulstforsch 1985; 55: 117–22. [PubMed] [Google Scholar]
- 23. Rehman I, Lowry DT, Adams C, Abdel‐Fattah R, Holly A, Yuspa SH, Hennings H. Frequent codon 12 Ki‐ras mutations in mouse skin tumors initiated by N‐methyl‐N'‐nitro‐N‐nitrosoguanidine and promoted by mezerein. Mol Carcinog 2000; 27: 298–307. [PubMed] [Google Scholar]
- 24. Saitoh A, Kimura M, Takahashi R, Yokoyama M, Nomura T, Izawa M, Sekiya T, Nishimura S, Katsuki M. Most tumors in transgenic mice with human c‐Ha‐ras gene contained somatically activated transgenes. Oncogene 1990; 5: 1195–200. [PubMed] [Google Scholar]
- 25. Pazzaglia S, Mancuso M, Primerano B, Rebessi S, Biozzi G, Covelli V, Saran A. Analysis of c‐Ha‐ras gene mutations in skin tumors induced in carcinogenesis‐susceptible and carcinogenesis‐resistant mice by different two‐stage protocols or tumor promoter alone. Mol Carcinog 2001; 30: 111–8. [DOI] [PubMed] [Google Scholar]
- 26. Pazzaglia S, Mancuso M, Rebessi S, Di Majo V, Tanori M, Biozzi G, Covelli V, Saran A. The genetic control of chemically and radiation‐induced skin tumorigenesis: a study with carcinogenesis‐susceptible and carcinogenesis‐resistant mice. Radiat Res 2002; 158: 78–83. [DOI] [PubMed] [Google Scholar]
- 27. Battalora MS, Spalding JW, Szczesniak CJ, Cape JE, Morris RJ, Trempus CS, Bortner CD, Lee BM, Tennant RW. Age‐dependent skin tumorigenesis and transgene expression in the Tg. AC (v‐Ha‐ras) transgenic mouse. Carcinogenesis 2001; 22: 651–9. [DOI] [PubMed] [Google Scholar]
- 28. Rodriguez‐Puebla ML, LaCava M, Bolontrade MF, Russell J, Conti CJ. Increased expression of mutated Ha‐ras during premalignant progression in SENCAR mouse skin. Mol Carcinog 1999; 26: 150–6. [PubMed] [Google Scholar]
- 29. Ise K, Nakamura K, Nakao K, Shimizu S, Harada H, Ichise T, Miyoshi J, Gondo Y, Ishikawa T, Aiba A, Katsuki M. Targeted deletion of the H‐ras gene decreases tumor formation in mouse skin carcinogenesis. Oncogene 2000; 19: 2951–6. [DOI] [PubMed] [Google Scholar]
- 30. Trempus CS, Bishop WR, Njoroge FG, Doll RJ, Battalora MS, Mahler JF, Haseman JK, Tennant RW. A farnesyl transferase inhibitor suppresses TPA‐mediated skin tumor development without altering hyperplasia in the ras transgenic Tg. AC mouse. Mol Carcinog 2000; 27: 24–33. [DOI] [PubMed] [Google Scholar]
- 31. Casanova ML, Larcher F, Casanova B, Murillas R, Fernandez‐Acenero MJ, Villanueva C, Martinez‐Palacio J, Ullrich A, Conti CJ, Jorcano JL. A critical role for ras‐mediated, epidermal growth factor receptor‐dependent angiogenesis in mouse skin carcinogenesis. Cancer Res 2002; 62: 3402–7. [PubMed] [Google Scholar]
- 32. Thompson TA, Haag JD, Lindstrom MJ, Griep AE, Lohse JK, Gould MN. Decreased susceptibility to NMU‐induced mammary carcinogenesis in transgenic rats carrying multiple copies of a rat ras gene driven by the rat Harvey ras promoter. Oncogene 2002; 18: 2797–804. [DOI] [PubMed] [Google Scholar]
- 33. Matsuoka Y, Hamaguchi T, Toriyama‐Baba H, Fukamachi K, Kawaguchi H, Kusunoki M, Yoshida H, Tsuda H. Rapid emergence of mammary preneoplastic and malignant lesions in human c‐Ha‐ras proto‐oncogene transgenic rats: possible application for screening of chemopreventive agents. Toxicol Pathol 2003; 31: in press. [DOI] [PubMed] [Google Scholar]