The overall goal of this proposal is to study the regulation of signaling pathways mediated by lysophosphatidic acid (LPA) and its associated receptors in ovarian cancer cells. LPA acid and its associated receptors, EDG2, EDG4 and EDG7 of the endothelial differentiation gene (EDG) family, have been shown to contribute to ovarian cancer cell proliferation and tumor invasion. Overexpression of EDG4 has been implicated in the progression of ovarian cancer. Thus, these LPA receptors could serve as therapeutic targets in ovarian cancer. In this proposal, we provided the first evidence for the regulation of EDG4 functions by the proapoptotic protein, Siva-1, and the focal adhesion molecule, TRIP6 (Thyroid Receptor Interacting Protein 6). Our long-term goal is to design nove strategies specifically targeting LPA receptors for therapeutic treatment.
Three specific aims will be addressed.
In Aim 1, a role for Siva-1 in down-regulation of LPA signaling and induction of apoptosis will be determined. Biochemical approaches and yeast genetics wiIl be utilized to determine the functional significance of the interaction between Siva-1 and EDG4.
In Aim 2, the role of TRIP6 in LPA-dependent, EDG4-mediated cell migration and mitogenic signaling will be explored by biochemical approaches and immunofluorescence microscopy.
In Aim 3, the specificity of Siva-1 and TRIP6 in regulating different LPA receptors will be determined by biochemical approaches. The knowledge obtained from this study will gain insight into the understanding of LPA signaling and regulation in ovarian cancer.

Agency
National Institute of Health (NIH)
Institute
National Cancer Institute (NCI)
Type
Research Project (R01)
Project #
5R01CA100848-03
Application #
6890335
Study Section
Pathology B Study Section (PTHB)
Program Officer
Sathyamoorthy, Neeraja
Project Start
2003-05-01
Project End
2007-04-30
Budget Start
2005-05-01
Budget End
2006-04-30
Support Year
3
Fiscal Year
2005
Total Cost
$258,100
Indirect Cost
Name
University of Alabama Birmingham
Department
Anatomy/Cell Biology
Type
Schools of Medicine
DUNS #
063690705
City
Birmingham
State
AL
Country
United States
Zip Code
35294
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E, Shuyu; Lai, Yun-Ju; Tsukahara, Ryoko et al. (2009) Lysophosphatidic acid 2 receptor-mediated supramolecular complex formation regulates its antiapoptotic effect. J Biol Chem 284:14558-71
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Lai, Yun-Ju; Lin, Weei-Chin; Lin, Fang-Tsyr (2007) PTPL1/FAP-1 negatively regulates TRIP6 function in lysophosphatidic acid-induced cell migration. J Biol Chem 282:24381-7
Lai, Yun-Ju; Chen, Chen-Shan; Lin, Weei-Chin et al. (2005) c-Src-mediated phosphorylation of TRIP6 regulates its function in lysophosphatidic acid-induced cell migration. Mol Cell Biol 25:5859-68
Luo, Yuhong; Lin, Fang-Tsyr; Lin, Weei-Chin (2004) ATM-mediated stabilization of hMutL DNA mismatch repair proteins augments p53 activation during DNA damage. Mol Cell Biol 24:6430-44
Wang, Bing; Liu, Kang; Lin, Fang-Tsyr et al. (2004) A role for 14-3-3 tau in E2F1 stabilization and DNA damage-induced apoptosis. J Biol Chem 279:54140-52
Xu, Jun; Lai, Yun-Ju; Lin, Weei-Chin et al. (2004) TRIP6 enhances lysophosphatidic acid-induced cell migration by interacting with the lysophosphatidic acid 2 receptor. J Biol Chem 279:10459-68
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