The primary interest of my group is bone growth and mammary gland tumorigenesis usinganimal model systems. We have the following three projects.1. Functions of fibroblast growth factor receptors (FGFRs). FGFRs constitute a family of 4 membrane-spanning tyrosine kinases, which serve as high affinity receptors for at least eighteen growth factors (FGF1-21). It has been shown that mutations in FGF receptors are responsible for at least nine human inherited diseases, all of which are caused by single amino acid mutations and exhibit extensive craniofacial, axial and/or appendicular bone abnormalities. To study functions of FGFs/FGFRs signals in development and to gain insights into mechanisms underlying these inherited diseases, mice carrying a variety of mutations including complete, isoform and conditional knockouts, and point mutations that mimic the human diseases have been created through gene targeting. Functional analysis of these mutant mice is being carried out.2. Functions of Smad genes. Smads constitute of a gene family of 9 members that serve asintracellular mediators of TGF-b signals. We have generated mouse mutants carrying targeted mutations in SMAD2-6. Our preliminary analysis on the mutant mice has revealed distinct functions of these genes in multiple biological processes. 3. Functions of Brca1 gene. We are studying functions of the breast tumor suppressor geneBrca1 in mammary gland development and tumor formation. Breast cancer is the most common cancer and the second leading cause of cancer mortality in women, with approximately one in 9 being affected over their lifetime. Analyzing our Brca1-null, isoform or conditional knockout models, we showed that BRCA1 is essential for genetic stability. Loss of BRCA1 increases mutation rates of all genes, including tumor suppressors and oncogenes, which result in tumor formation. We are continuing to study mechanisms of BRCA1 associated tumorigenesis and seeking efficient ways to prevent the transformation process from happening.

Agency
National Institute of Health (NIH)
Institute
National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK)
Type
Intramural Research (Z01)
Project #
1Z01DK056001-02
Application #
6432177
Study Section
(GDDB)
Project Start
Project End
Budget Start
Budget End
Support Year
2
Fiscal Year
2000
Total Cost
Indirect Cost
Name
U.S. National Inst Diabetes/Digst/Kidney
Department
Type
DUNS #
City
State
Country
United States
Zip Code
Lahusen, Tyler J; Deng, Chu-Xia (2015) SRT1720 induces lysosomal-dependent cell death of breast cancer cells. Mol Cancer Ther 14:183-92
Cao, Liu; Xu, Xiaoling; Cao, Longyue L et al. (2007) Absence of full-length Brca1 sensitizes mice to oxidative stress and carcinogen-induced tumorigenesis in the esophagus and forestomach. Carcinogenesis 28:1401-7
Tominaga, Y; Wang, A; Wang, R-H et al. (2007) Genistein inhibits Brca1 mutant tumor growth through activation of DNA damage checkpoints, cell cycle arrest, and mitotic catastrophe. Cell Death Differ 14:472-9
De Soto, Joseph A; Wang, Xianyan; Tominaga, Yohei et al. (2006) The inhibition and treatment of breast cancer with poly (ADP-ribose) polymerase (PARP-1) inhibitors. Int J Biol Sci 2:179-85
Smolen, Gromoslaw A; Muir, Beth; Mohapatra, Gayatry et al. (2006) Frequent met oncogene amplification in a Brca1/Trp53 mouse model of mammary tumorigenesis. Cancer Res 66:3452-5
Overholtzer, Michael; Zhang, Jianmin; Smolen, Gromoslaw A et al. (2006) Transforming properties of YAP, a candidate oncogene on the chromosome 11q22 amplicon. Proc Natl Acad Sci U S A 103:12405-10
Kim, Byung-Gyu; Li, Cuiling; Qiao, Wenhui et al. (2006) Smad4 signalling in T cells is required for suppression of gastrointestinal cancer. Nature 441:1015-9
Gautam, Dinesh; Han, Sung-Jun; Hamdan, Fadi F et al. (2006) A critical role for beta cell M3 muscarinic acetylcholine receptors in regulating insulin release and blood glucose homeostasis in vivo. Cell Metab 3:449-61
Kim, Sang Soo; Cao, Liu; Lim, Sung-Chul et al. (2006) Hyperplasia and spontaneous tumor development in the gynecologic system in mice lacking the BRCA1-Delta11 isoform. Mol Cell Biol 26:6983-92
Xu, Xiaoling; Kobayashi, Shogo; Qiao, Wenhui et al. (2006) Induction of intrahepatic cholangiocellular carcinoma by liver-specific disruption of Smad4 and Pten in mice. J Clin Invest 116:1843-52

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