Rosa26-hHRAS Mice

Catalog Number: I001213

Strain Name: C57BL/6JCya-Gt(ROSA)26Sorem1(hHRAS*c.450+180A>G)/Cya

Genetic Background: C57BL/6JCya

 

Strain Description

The HRas oncogene (HRAS), also known as the Harvey Rat Sarcoma Viral Oncogene Homolog (HRAS), is a member of the Ras oncogene family, which also includes KRAS and NRAS. All members of this family are associated with the development of mammalian sarcoma retroviruses [1]. HRAS encodes the H-Ras protein, a small GTPase responsible for transmitting signals from cell surface receptors to the nucleus, regulating cell proliferation, survival, and differentiation. HRAS is primarily expressed in various tissues, including the brain, heart, and skeletal muscle, and is involved in controlling the cellular response to growth factors. As a member of the small GTPase family, HRAS acts as a molecular switch, cycling between active and inactive states to influence key cellular processes. Mutations in the HRAS gene can lead to abnormal signal transduction, commonly found in tumors of stratified epithelial tissues, such as bladder cancer, thyroid cancer, and head and neck squamous cell carcinoma. Additionally, HRAS is associated with Costello syndrome, a genetic disorder characterized by developmental delays and an increased risk of tumors [2-3].

Early studies have shown that genotoxic carcinogens shorten the latency period and increase the incidence of malignant tumors in rasH2 mice, which carry the human HRAS (c-Ha-ras) oncogene, compared to non-transgenic mice. Therefore, rasH2 mice are ideal animal models for rapid carcinogenicity testing [4-5]. Further research has shown that F1 hybrid mice (CB6F1 background rasH2 mice) obtained by mating male C57BL/6J mice carrying the human prototype c-Ha-ras gene with female BALB/c mice are significantly more sensitive to both mutagenic and non-mutagenic carcinogens than control mice [5]. These mice are highly sensitive to the carcinogenicity of both genotoxic and non-genotoxic compounds while showing no response to non-carcinogens [6]. Between 12 to 18 months of age, rasH2 mice primarily develop spontaneous alveolar adenomas/bronchial adenomas/adenocarcinomas, splenic hemangiomas/hemangiosarcomas, and a smaller number of skin and gastric papillomas and lymphomas [4]. In the 1990s, this mouse model was officially approved by the FDA for carcinogenicity evaluations in drug safety assessments, reducing the standard two-year carcinogenicity test in common rodents to six months.

The Rosa26-hHRAS mouse model is a humanized model constructed by integrating a human HRAS gene with the c.450+180A>G mutation into the Rosa26 safe harbor site in mice using gene editing technology. The introduction of the c.450+180A>G mutation significantly enhances HRAS gene expression. This model can be used for rapid in vivo testing of the carcinogenicity of genotoxic and non-genotoxic compounds, studying the impact of HRAS oncogene point mutations on tumorigenesis and development, and developing tumor prevention or suppression therapies.

Strain Strategy


Figure 1. Gene editing strategy of Rosa26-hHRAS mice. The Mutant human HRAS genome cassette was cloned into the intron 1 of ROSA26 in reverse orientation. The c.450+180A>G point mutation was introduced into the intron 4 of Human HRAS.

Application

  • Rapid in vivo test for carcinogenicity of genotoxic and non-genotoxic compounds;
  • Impact of HRAS oncogene point mutations on tumorigenesis and development.

 

Validation Data

1. Expression of the human HRAS gene

Figure 2. Detection of human HRAS gene expression in the liver, spleen, and lungs of 6-week-old male heterozygous Rosa26-hHRAS mice and wild-type mice (WT) (n=3). RT-qPCR results show that the human HRAS gene is expressed in the liver, spleen, and lungs of Rosa26-hHRAS mice, with different levels of hHRAS mRNA expression in different tissues, and the highest expression observed in the lungs. (ND: Not detected)

2. Expression of the human HRAS protein


Figure 3. Detection of human HRAS protein expression in the lungs of 6-week-old male heterozygous Rosa26-hHRAS mice and wild-type mice (WT) (n=3). Western Blot results show that the human HRAS protein (Human H-Ras) is expressed in the lungs of heterozygous Rosa26-hHRAS mice*.

*The antibody used in this assay for human H-Ras protein shows cross-species reactivity and can recognize the homologous H-Ras protein in mice.

 

References

[1]Parikh C, Subrahmanyam R, Ren R. Oncogenic NRAS, KRAS, and HRAS exhibit different leukemogenic potentials in mice. Cancer Res. 2007 Aug 1;67(15):7139-46.
[2]Untch BR, Dos Anjos V, Garcia-Rendueles MER, Knauf JA, Krishnamoorthy GP, Saqcena M, Bhanot UK, Socci ND, Ho AL, Ghossein R, Fagin JA. Tipifarnib Inhibits HRAS-Driven Dedifferentiated Thyroid Cancers. Cancer Res. 2018 Aug 15;78(16):4642-4657.
[3]Wu XY, Liu WT, Wu ZF, Chen C, Liu JY, Wu GN, Yao XQ, Liu FK, Li G. Identification of HRAS as cancer-promoting gene in gastric carcinoma cell aggressiveness. Am J Cancer Res. 2016 Sep 1;6(9):1935-1948.
[4]Maronpot RR, Mitsumori K, Mann P, Takaoka M, Yamamoto S, Usui T, Okamiya H, Nishikawa S, Nomura T. Interlaboratory comparison of the CB6F1-Tg rasH2 rapid carcinogenicity testing model. Toxicology. 2000 May 5;146(2-3):149-59.
[5]Yamamoto S, Urano K, Nomura T. Validation of transgenic mice harboring the human prototype c-Ha-ras gene as a bioassay model for rapid carcinogenicity testing. Toxicol Lett. 1998 Dec 28;102-103:473-8.
[6]Sehata S, Maejima T, Watanabe M, Ogata S, Makino T, Tanaka K, Manabe S, Takaoka M. Twenty-six-Week carcinogenicity study of chloroform in CB6F1 rasH2-transgenic mice. Toxicol Pathol. 2002 May-Jun;30(3):328-38.