Development of ferret as a human lung cancer model by injecting 4-(N-methyl-N-nitrosamino)-1-(3-pyridyl)-1-butanone (NNK)

Abstract

Objective Development of new animal lung cancer models that are relevant to human lung carcinogenesis is important for lung cancer research. Previously we have shown the induction of lung tumor in ferrets (Mustela putorius furo) exposed to both tobacco smoke and a tobacco carcinogen (4-(N-Methyl-N-nitrosamino)-1-(3-pyridyl)-1-butanone, NNK). In the present study, we investigated whether NNK treatment alone induces both preneoplastic and neoplastic lesions in the lungs of ferrets. Methods We exposed ferrets to NNK by i.p. injection of NNK (50 mg/kg BW) once a month for four consecutive months and then followed up for 24, 26 and 32 weeks. The incidences of pulmonary preneoplastic and neoplastic lesions were assessed by histopathological examination. The expressions of α7 nicotinic acetylcholine receptor (α7 nAChR, which has been shown to promote lung carcinogenesis) and its related molecular biomarkers in lungs were examined by immunohistochemistry and/or Western blotting analysis. Results Ferrets exposed to NNK alone developed both preneoplastic lesions (squamous metaplasia, dysplasia and atypical adenomatous hyperplasia) and tumors (squamous cell carcinoma, adenocarcinoma and adenosquamous carcinoma), which are commonly seen in humans. The incidence of tumor induced by NNK was time-dependent in the ferrets (16.7%, 40.0% and 66.7% for 24, 26 and 32 weeks, respectively). α7 nAChR is highly expressed in the ferret bronchial/bronchiolar epithelial cells, and alveolar macrophages in ferrets exposed to NNK, and in both squamous cell carcinoma and adenocarcinoma of the ferrets. In addition, we observed the tendency for an increase in phospho-ERK and cyclin D1 protein levels (p = 0.081 and 0.080, respectively) in the lungs of ferrets exposed to NNK. Conclusion The development of both preneoplastic and neoplastic lesions in ferret lungs by injecting NNK alone provides a simple and highly relevant non-rodent model for studying biomarkers/molecular targets for the prevention, detection and treatment of lung carcinogenesis in humans.

Tobacco carcinogen NNK-induced lung cancer animal models and associated carcinogenic mechanisms

“…They found that 16.7% of ferrets developed tumors 24 weeks after NNK injection (50 mg/kg), and after 26 and 32 weeks, the proportion increased to 40% and 66.7%, respectively. These results indicated that the injection of NNK alone could induce both preneoplastic lesions (squamous metaplasia, dysplasia, and atypical adenomatous hyperplasia) and tumors (squamous cell carcinoma, adenocarcinoma, and adenosquamous carcinoma) in lung, which were commonly seen in humans [24].…”

“…Aizawa et al [24] also used this scheme in male ferrets (3-5-month old) without smoke exposure. They found that 16.7% of ferrets developed tumors 24 weeks after NNK injection (50 mg/kg), and after 26 and 32 weeks, the proportion increased to 40% and 66.7%, respectively.…”

Phenotypic Modification of Human Airway Epithelial Cells in Air–Liquid Interface Culture Induced by Exposure to the Tobacco-Specific Nitrosamine 4-(Methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK)

“…Given the higher range of NNK contained in some tobacco products as well as the concentration used to provoke neoplastic change in experimental animals studies [18], the concentration used in the current in vitro study (100 mg/ml) was appropriate inasmuch as it provoked phenotypic transitions documented in other studies while retaining cell viability. In vitro cell culture models have been widely appropriated for mechanistic studies of a variety of infectious agents on differing epithelia of humans and experimental animals [19][20][21][22][23].…”

Tumor-penetration and antitumor efficacy of cetuximab are enhanced by co-administered iRGD in a murine model of human NSCLC

“…The fixed tumor tissues were embedded in paraffin and cut into 3–5 µm sections (20). The experiment was performed on with a streptavidin-peroxidase system (OriGene Technologies, Inc., Beijing, China).…”