Cre-loxP-controlled periodic Aurora-A overexpression induces mitotic abnormalities and hyperplasia in mammary glands of mouse models.
Aurora-A, a serine/threonine mitotic kinase, was reported to be overexpressed in various human cancers, and its overexpression induces aneuploidy, centrosome amplification and tumorigenic transformation in cultured human and rodent cells. However, the underlying mechanisms and pathological settings by which Aurora-A promotes tumorigenesis are largely unknown. Here, we created a transgenic mouse model to investigate the involvement of Aurora-A overexpression in the development of mammary glands and tumorigenesis using a Cre-loxP system. The conditional expression of Aurora-A resulted in significantly increased binucleated cell formation and apoptosis in the mammary epithelium. The surviving mammary epithelial cells composed hyperplastic areas after a short latency. Induction of Aurora-A overexpression in mouse embryonic fibroblasts prepared from the transgenic mice also led to aberrant mitosis and binucleated cell formation followed by apoptosis. The levels of p53 protein were remarkably increased in these Aurora-A-overexpressing cells, and the apoptosis was significantly suppressed by deletion of p53. Given that no malignant tumor formation was found in the Aurora-A-overexpressing mouse model after a long latency, additional factors, such as p53 inactivation, are required for the tumorigenesis of Aurora-A-overexpressing mammary epithelium. Our findings indicated that this mouse model is a useful system to study the physiological roles of Aurora-A and the genetic pathways of Aurora-A-induced carcinogenesis.
Department of Tumor Genetics and Biology, Graduate School of Medical Sciences, Kumamoto University, 1-1-1 Honjo, Kumamoto 860-8556, Japan.
Dongwei
D
Zhang
Toru
T
Hirota
Tomotoshi
T
Marumoto
Michio
M
Shimizu
Naoko
N
Kunitoku
Takashi
T
Sasayama
Yoshimi
Y
Arima
Liping
L
Feng
Misao
M
Suzuki
Motohiro
M
Takeya
Hideyuki
H
Saya
D000818:Animals; D017209:Apoptosis / Q000502:physiology; D064096:Aurora Kinase A; D064127:Aurora Kinases; D001483:Base Sequence; D002471:Cell Transformation, Neoplastic; D005455:Fluorescent Antibody Technique; D006965:Hyperplasia; D008321:Mammary Glands, Animal / Q000473:pathology*; D008325:Mammary Neoplasms, Experimental / Q000201:enzymology / Q000473:pathology; D051379:Mice; D008822:Mice, Transgenic; D008938:Mitosis / Q000502:physiology*; D023421:Models, Animal; D008969:Molecular Sequence Data; D017346:Protein Serine-Threonine Kinases / Q000235:genetics / Q000378:metabolism*; D045522:Recombinases / Q000378:metabolism / Q000502:physiology*; D016159:Tumor Suppressor Protein p53 / Q000502:physiology
D045522:Recombinases; D016159:Tumor Suppressor Protein p53; C576918:Aurka protein, mouse; D064096:Aurora Kinase A; D064127:Aurora Kinases; D017346:Protein Serine-Threonine Kinases