Division of Molecular and Life Science, Pohang University of Science and Technology, Pohang, Kyungbuk 790-784, Republic of Korea.
J Biol Chem. 2011 Jul 8;286(27):24036-45. doi: 10.1074/jbc.M110.209908. Epub 2011 May 20.
Lysophosphatidic acid (LPA) is a bioactive phospholipid that affects various biological functions, such as cell proliferation, migration, and survival, through LPA receptors. Among them, the motility of cancer cells is an especially important activity for invasion and metastasis. Recently, AMP-activated protein kinase (AMPK), an energy-sensing kinase, was shown to regulate cell migration. However, the specific role of AMPK in cancer cell migration is unknown. The present study investigated whether LPA could induce AMPK activation and whether this process was associated with cell migration in ovarian cancer cells. We found that LPA led to a striking increase in AMPK phosphorylation in pathways involving the phospholipase C-β3 (PLC-β3) and calcium/calmodulin-dependent protein kinase kinase β (CaMKKβ) in SKOV3 ovarian cancer cells. siRNA-mediated knockdown of AMPKα1, PLC-β3, or (CaMKKβ) impaired the stimulatory effects of LPA on cell migration. Furthermore, we found that knockdown of AMPKα1 abrogated LPA-induced activation of the small GTPase RhoA and ezrin/radixin/moesin proteins regulating membrane dynamics as membrane-cytoskeleton linkers. In ovarian cancer xenograft models, knockdown of AMPK significantly decreased peritoneal dissemination and lung metastasis. Taken together, our results suggest that activation of AMPK by LPA induces cell migration through the signaling pathway to cytoskeletal dynamics and increases tumor metastasis in ovarian cancer.
溶血磷脂酸(LPA)是一种生物活性磷脂,通过 LPA 受体影响各种生物学功能,如细胞增殖、迁移和存活。其中,癌细胞的运动性对于侵袭和转移是一种特别重要的活性。最近,作为能量感应激酶的 AMP 激活蛋白激酶(AMPK)被证明可以调节细胞迁移。然而,AMPK 在癌细胞迁移中的具体作用尚不清楚。本研究探讨了 LPA 是否可以诱导 AMPK 激活,以及该过程是否与卵巢癌细胞的迁移有关。我们发现,LPA 导致 SKOV3 卵巢癌细胞中涉及磷脂酶 C-β3(PLC-β3)和钙/钙调蛋白依赖性蛋白激酶激酶β(CaMKKβ)的 AMPK 磷酸化显著增加。AMPKα1、PLC-β3 或(CaMKKβ)的 siRNA 介导的敲低削弱了 LPA 对细胞迁移的刺激作用。此外,我们发现 AMPKα1 的敲低消除了 LPA 诱导的小 GTPase RhoA 和 ezrin/radixin/moesin 蛋白的激活,这些蛋白调节膜动力学作为膜-细胞骨架连接物。在卵巢癌异种移植模型中,AMPK 的敲低显著减少了腹膜扩散和肺转移。总之,我们的结果表明,LPA 通过信号通路诱导 AMPK 的激活,从而诱导细胞迁移,调节细胞骨架动力学,并增加卵巢癌的肿瘤转移。