11:10-12:00, Rm 103

Cell: signal transductionL-18-88Activation of AMP-activated protein kinase is essential for LPA-inducedcell migration in ovarian cancer cellsEung-Kyun Kim¹ , ², Ji-Man Park², Seyoung Lim², Jung Woong Choi¹, Hyeon SooKim³, Heon Seok², Jeong Kon Seo², Keunhee Oh⁴, Dong-Sup Lee⁴, Kyong TaiKim¹, Sung Ho Ryu¹and Pann-Ghill Suh¹ , ² , *¹Division of Molecular and Life Science, Pohang University of Science and Technology, Pohang,Kyungbuk 790-784, Korea, ²School of Nano-Bioscience & Chemical Engineering, Ulsan NationalInstitute of Science and Technology, Ulsan, Korea, ³Department of Anatomy, Korea University College ofMedicine, 126-1, 5-ga, Anam-dong, Seongbuk-gu, Seoul 136-701, Korea, ⁴Transplantation ResearchInstitute, College of Medicine, Seoul National University, Seoul, KoreaLysophosphatidic acid (LPA) is a bioactive phospholipid that affects various biologicalfunctions through LPA receptors. Among them, the motility of cancer cells is an especiallyimportant activity for invasion and metastasis. Recently, AMP-activated protein kinase(AMPK), an energy-sensing kinase, was shown to regulate cell migration. However, thespecific role of AMPK in cancer cell migration is unknown. The present study investigatedwhether LPA could induce AMPK activation and whether this process was associated withcell migration in ovarian cancer cells. We found that LPA led to a striking increase in AMPKphosphorylation in pathways involving the PLC-β3 and CaMKKβin SKOV3 ovarian cancercells. Knockdown of AMPKα1, PLC-β3, or CaMKKβimpaired the stimulatory effects of LPAon cell migration. Furthermore, we found that knockdown of AMPKα1 abrogated LPAinducedactivation of RhoA and ezrin/radixin/moesin (ERM) proteins. The role of AMPK wasfurther confirmed in vivo using xenografts. Knockdown of AMPK decreased peritonealdissemination and lung metastasis. Taken together, these results suggested that activationof AMPK by LPA induces cell migration through the RhoA-ROCK-ERM pathway. This studymay provide the basis for new therapies to control the ovarian cancer metastasis.L-18-89Clusterin-induced matrix metalloproteinase-9 expression through ERK,JNK and nuclear factor-kB in macrophagesYoung-Jun Shim, Byeong-Ho Kang, Hye-Sook Jeon and Bon-Hong MinDepartment of Pharmacology and BK21 Program in Biomedical Sciences, College of Medicine,Korea University, Seoul 136-705, KoreaClusterin (CLU) has been implicated in tissue remodeling, metastasis, and inflammation,which these processes are associated with ECM degradation. Thus, we examinedwhether CLU enhances expression of MMP-9 and demonstrated that the production ofMMP-9 protein and mRNA is promoted by CLU in macrophage-like Raw 264.7 cells. CLUupregulated MMP-9 expression in a time- and dose- dependent manner. To explore theintracellular signaling pathways, cells were treated with inhibitors of MAPK pathways.CLU-stimulated MMP-9 induction was significantly attenuated by inhibition of ERK1/2 andJNK by PD98059 and SP600125, respectively. Indeed, CLU stimulated a time-dependentphosphorylation of both ERK1/2 within 60 min. Moreover, the translocation of NF-kB p65into the nucleus and the degradation of IkB-alpha are involved in the CLU-induced MMP-9 expression. MMP-9 promoter activity was facilitated by CLU treatment in cellstransfected with wild-type MMP-9-Luc, which was inhibited by PD98059, SP600125.Collectively, these results propose that phosphorylation of ERK1/2, JNK, and NF-kBtransactivation is indispensable for CLU-induced MMP-9 production. [This work wassupported by the Korea Science and Engineering Foundation (KOSEF) grant funded bythe Korea government (MEST) (No. 2009-009-1418)]290 Korean Society for Biochemistry and Molecular Biology