GnRH regulates trophoblast invasion via RUNX2-mediated MMP2/9 expression.

We hypothesized that Runt-related transcription factor 2 (RUNX2), matrix metalloproteinase (MMP)2 and MMP9 are involved in basal and gonadotrophin-releasing hormone (GnRH)-induced human extravillous trophoblast (EVT) cell invasion. Our finding indicates that GnRH-induced RUNX2 expression enhances the invasive capacity of EVT cells by modulating the expression of MMP2 and MMP9. GnRH is expressed in first-trimester placenta and exerts pro-invasive effects on EVT cells in vitro. RUNX2 regulates MMP2 and MMP9 expression and is often associated with invasive phenotypes. First-trimester human placenta (n = 9) was obtained from women undergoing elective termination of pregnancy. The localization of RUNX2, MMP2 and MMP9 in first-trimester human placenta was examined by immunohistochemistry. Primary or immortalized (HTR-8/SVneo) EVT cells were treated alone or in combination with GnRH, GnRH antagonist Antide, MAPK kinase inhibitor PD98095, phosphatidylinositol 3-kinase inhibitor LY294002, MMP2/9 inhibitor or small interfering RNAs (siRNAs) targeting RUNX2, MMP2 and/or MMP9. Protein and mRNA levels were measured by western blot and RT-PCR, respectively. Cell invasiveness was evaluated by transwell Matrigel or collagen I invasion assays. RUNX2, MMP2 and MMP9 were detected in the cell column regions of human first-trimester placental villi. GnRH treatment increased RUNX2 mRNA and protein levels in HTR-8/SVneo cells and primary EVTs, and these effects were attenuated by co-treatment with Antide, PD98095 or LY294002. Down-regulation of RUNX2 by siRNA reduced basal and GnRH-induced MMP2/9 expression and cell invasion. Moreover, pharmacological inhibition or siRNA-mediated knockdown of MMP2/9 reduced basal and GnRH-induced cell invasion. The lack of an in vivo model is the major limitation of our in vitro study. Our findings provide important insight into the functions of the GnRH - GnRH receptor system in early implantation and placentation. Not applicable. This research was supported by Canadian Institutes of Health Research (Grant #143317) to P.C.K.L. The authors have nothing to disclose.

Peng B ，Zhu H ，Klausen C ，Ma L ，Wang YL ，Leung PC ... -  《-》

Gonadotropin-releasing hormone regulates human trophoblastic cell invasion via TWIST-induced N-cadherin expression.

Peng B ，Zhu H ，Leung PC 《-》

Activin A Increases Human Trophoblast Invasion by Inducing SNAIL-Mediated MMP2 Up-Regulation Through ALK4.

Li Y ，Klausen C ，Zhu H ，Leung PC ... -  《-》

Prostaglandin F(2α) stimulates adhesion, migration, invasion and proliferation of the human trophoblast cell line HTR-8/SVneo.

The amount of prostaglandin F2α (PGF2α) in the uterine lumen increases during the window of implantation in many mammals, including humans. We hypothesized that PGF2α regulates processes related to human embryo implantation. The effect of PGF2α was studied using an in vitro model of human extravillous trophoblast (EVT) cell line (HTR-8/SVneo). Adhesion, proliferation, invasion and migration assays, zymography for metalloproteinases (MMP) activity, and gene/protein expression analyses were applied. Doses of 100 nM and/or 1 μM of PGF2α and fluprostenol were used. PGF2α receptor (PTGFR), MMP9 and MMP2 proteins in the human first trimester placenta were localized by immunohistochemistry and immunofluorescence. This study is the first reporting the expression of PTGFR protein in the first trimester placenta, as well as in HTR-8/SVneo cells. PGF2α and fluprostenol increased HTR-8/SVneo cell proliferation and adhesion to extracellular matrix protein (P < 0.05). This effect was abolished by mitogen activated protein kinases (MAPK) inhibitor. PGF2α induced phosphorylation of focal adhesion kinase and MAPK1/3 (P < 0.05). PGF2α increased mRNA content and protein activity of MMP9, and gene and protein expression of interleukin-6 (P < 0.05). EVT cell migration and invasiveness were stimulated by PGF2α (P < 0.05). The PGF2α effect on cell invasion was reduced by inhibitors of MMP2, MMP9 and mTOR. In all experiments, the stimulatory effects of PGF2α were diminished by using a PTGFR antagonist. Our findings suggest a significant role for PGF2α in mechanisms associated with implantation. PGF2α acting by PTGFR in HTR-8/SVneo cells stimulates their adhesion and proliferation through the MAPK signaling pathway and increases invasiveness inducing MMP proteolytic activity and mTOR signaling.

Baryla M ，Kaczynski P ，Goryszewska E ，Riley SC ，Waclawik A ... -  《-》

Expression of Gadd45α in human early placenta and its role in trophoblast invasion.

Well-controlled trophoblast migration and invasion at the maternal-foetal interface are crucial events for normal placentation and successful pregnancy. Growing evidence has revealed that growth arrest and DNA damage-inducible 45 alpha (Gadd45α) participates in tumour migration and invasion as a tumour suppressor. However, the expression and function of Gadd45α in trophoblasts is unknown. This study aimed to determine the Gadd45α expression and function in the human first trimester placenta and identify the underlying mechanisms. The expression of Gadd45α in human first trimester placenta was determined using immunohistochemistry. HTR8/SVneo cell line was used to investigate the effects of Gadd45α on proliferation, apoptosis, migration/invasion, matrix metalloproteinase (MMP)2/9 activities, and tissue inhibitor of metalloproteinase (TIMP)1/2 expression using cell proliferation assays, flow cytometric analysis, transwell migration/invasion assays, gelatin gel zymography, and western blotting, respectively. Moreover, a placental villous explant model was employed to verify its functions in placentation. Gadd45α was strongly expressed in syncytiotrophoblasts and trophoblast columns of human placental villi, extravillous trophoblast cells and glandular epithelium within the maternal decidua. Gadd45α knockdown significantly promoted migration and invasion of HTR8/SVneo cells, whereas it did not affect cell proliferation or apoptosis. Silencing Gadd45α also enhanced trophoblast outgrowth and migration in placental explants. These effects were related to increased activities of MMP2/9 and the decreased expression of TIMP1/2. Gadd45α may be involved in human trophoblast migration and invasion and may function as an important negative regulator at the foetal-maternal interface during early pregnancy by directly or indirectly regulating MMP2/9 activities.

Liu X ，Mu H ，Luo X ，Xiao X ，Ding Y ，Yin N ，Deng Q ，Qi H ... -  《-》