Imprinted genes are involved in several cellular processes and perform a variety of functions, including cell cycle control, G-protein-coupled receptor signaling, and intracellular signaling, thereby influencing both pre- and postnatal growth and development through endocrine/paracrine pathways[6]. More recent data have shown that abnormal expression of several imprinted genes including decorin can cause YM155 mouse tumorigenesis. Decorin is a maternally expressed imprinted gene that belongs to the small leucine-rich proteoglycan

(SLRP) gene family and has been implicated in the control of cell proliferation [7, 8]. Reduced expression of decorin facilitates tumorigenesis and cell growth [9, 10]. Decorin is a functional component of the ECM,

and is also considered to be a novel biological selleck screening library ligand for EGFR, which is frequently expressed at elevated levels in multiple cancers of epithelial origin. Interactions between these factors can inhibit cell growth during tissue remodeling and cancer development [11]. In addition to serving as a ligand for EGFR, decorin can bind to various forms of active TGF-β through its core protein and can neutralize the activity of TGF-β[12]. Abnormal expression of decorin has been found in many tumors, including lymphoma and human breast carcinoma [13, 14]. In this study, gene expression profiles of normal mammary glands and spontaneous breast cancer tissues from TA2 mice were detected by Affymetrix Mouse Genome 430 2.0 Arrays for Edoxaban the first time. The expression data were analyzed by the MAS5.0 [4], BGX[15], and Array2BIO[16] methods. Based on the candidate genes identified by expression profiling, we hypothesized that abnormal expression of decorin, EGFR, and cyclin D1 might induce carcinogenesis of mammary gland epithelial cells in TA2 mice. Methods Animals and Sampling Female TA2 mice (five month-old TA2 mice and spontaneous breast cancer-bearing TA2 mice) were purchased from

the Experimental Animal Center of Tianjin Medical University. The Animal Fer-1 molecular weight Ethics Committee of National Research Institute for Family Planning Beijing approved the animal experimentation protocols and all animal experiments were performed according to guidelines (Guidelines for the Care and Use of Laboratory Animals) established by the Chinese Council on Animal Care. A total of 12 five month-old mice and 28 cancer-bearing mice were used in this study. As for the 28 cancer-bearing mice, spontaneous breast cancer was found with an average of 307 days after birth (213 days to 408 days). After euthanasia, mammary glands and spontaneous breast cancer tissues were collected from each cancer-bearing animal. Two abdominal mammary glands were collected from the five month-old mice (Group A). One was immediately frozen in liquid nitrogen and stored at -70°C, and the other was fixed in 4% formalin and embedded in paraffin.