title: A novel mouse model for de novo Melanoma.
abstract: Nevus-associated melanomas arise from pre-existing benign lesions, but de novo melanomas can also develop in the absence of such lesions. Few studies have addressed the latter phenomenon because no animal models have been described in which melanomas clearly develop in a de novo manner. In this study, we have address this need in defining RFP-RET-transgenic mice (RET mice) as a mouse model for multi-step melanomagenesis that proceeds via tumor-free, benign, premalignant, and malignant stages. Melanomas from RET mice exhibited decreased expression levels of endothelin receptor B (Ednrb) compared with benign tumors. In RET mice that were heterozygous for Ednrb (Ednrb+/-;RET mice), >80% of the arising primary tumors were malignant. Life span after tumor development in the mice was significantly shorter than in RET mice. Lung metastasis after tumor development was significantly higher than in RET mice. The observed process of melanomagenesis in Ednrb+/-;RET mice, which proceeded without a pre-existing benign lesion, along with the emergent characteristics in the model after tumor development corresponded well with the formation of de novo melanoma in humans. Our findings define a novel transgenic mouse model for de novo melanoma and suggest that reduced expression of Ednrb might facilitate the development of de novo melanoma in humans.
authors.affiliation: Unit of the Environmental Health Sciences, Department of Biomedical Sciences, College of Life and Health Sciences, Chubu University, Kasugai, Aichi, Japan.
authors.forename: Mayuko Y
authors.initials: MY
authors.lastname: Kumasaka
authors.forename: Ichiro
authors.initials: I
authors.lastname: Yajima
authors.forename: Khaled
authors.initials: K
authors.lastname: Hossain
authors.forename: Machiko
authors.initials: M
authors.lastname: Iida
authors.forename: Toyonori
authors.initials: T
authors.lastname: Tsuzuki
authors.forename: Tamio
authors.initials: T
authors.lastname: Ohno
authors.forename: Masahide
authors.initials: M
authors.lastname: Takahashi
authors.forename: Masashi
authors.initials: M
authors.lastname: Yanagisawa
authors.forename: Masashi
authors.initials: M
authors.lastname: Kato
mesh_terms: D000818:Animals; D015153:Blotting, Western; D004195:Disease Models, Animal; D007150:Immunohistochemistry; D008546:Melanoma, Experimental / Q000235:genetics* / Q000473:pathology; D051379:Mice; D008822:Mice, Transgenic; D044023:Receptor, Endothelin B / Q000235:genetics*; D017466:Receptors, Endothelin / Q000235:genetics*; D020133:Reverse Transcriptase Polymerase Chain Reaction; D012878:Skin Neoplasms / Q000235:genetics* / Q000473:pathology
chemical_list: D044023:Receptor, Endothelin B; D017466:Receptors, Endothelin