ABSTRACT
The original version of this article contained an error in the published figures Fig 2 and Fig 3f, where the information was inadvertently duplicated. This error does not alter the conclusions of the paper. The corrected figures are published in this correction notice. The authors sincerely apologize for this error.
ABSTRACT
Lysophosphatidic acid (LPA) is a biolipid that has diverse biological activities implicated in ovarian cancer initiation and progression. Previous studies have shown the critical role of the Rho/Rho-associated kinase (ROCK) pathway in LPA-induced ovarian cancer progression. However, detailed underlying mechanism by which the Rho/ROCK pathway induces ovarian cancer cell invasion is still incompletely understood. In the present study, we observed that the Rho/ROCK pathway is implicated in the production of proteolytic enzymes, leading to LPA-induced ovarian cancer cell invasion. LPA induced matrix metalloproteinase (MMP)-9 expression in CAOV-3 and PA-1 cells and urokinase-type plasminogen activator (uPA) expression in SKOV-3 cells. LPA-induced proteolytic enzyme expression was required for the invasion of ovarian cancer cells expressing corresponding enzymes. Pretreatment of cells with a pharmacological inhibitor of Rho/ROCK (Y-27632) or overexpression of a dominant-negative mutant of Rho (Rho N19) profoundly inhibited LPA-induced proteolytic enzyme expression as well as the invasive potential of ovarian cancer cells. In addition, transfection with dominant-negative Ras (Ras N17) significantly inhibited LPA-induced Rho activation as well as MMP-9 and uPA expression. Consistently, Y-27632 reduced LPA-induced nuclear factor (NF)-κB activation that is critical for proteolytic enzyme expression and cellular invasion. Collectively, we demonstrate a mechanism by which LPA promotes ovarian cancer progression through coordinate activation of a Ras/Rho/ROCK/NF-κB signaling pathway and the proteolytic enzyme secretion, providing novel biomarkers and promising therapeutic targets for ovarian cancer cell progression.