Reproductive Cell Biology Laboratory, National Institute of Immunology, Aruna Asaf Ali Marg, New Delhi, India.
PLoS One. 2012;7(1):e29745. doi: 10.1371/journal.pone.0029745. Epub 2012 Jan 3.
This study examines the IL-11 mediated activation of downstream signaling and expression of effector molecules to resolve the controversies associated with the IL-11 mediated regulation of the invasiveness of two commonly used trophoblastic cell models viz. JEG-3 and HTR-8/SVneo cells. It has been reported that IL-11 increases the invasiveness of JEG-3 cells while, reduces the invasiveness of HTR-8/SVneo cells. Invasion assay performed simultaneously for both the cell lines confirmed the above findings. In addition, HTR-8/SVneo cells showed a higher basal invasiveness than JEG-3 cells. Western blot showed the IL-11 mediated activation of STAT3(tyr705) and STAT1(tyr701) in both the cell lines. However, IL-11 activated the ERK1/2 phosphorylation in JEG-3 cells but, inhibited it in HTR-8/SVneo cells. Within 10 min of IL-11 treatment, p-STAT3(tyr705) was localized inside the nucleus of both the cell lines but, there was enhanced co-localization of protein inhibitor of activated STAT1/3 (PIAS1/3) and p-STAT3(tyr705) in HTR-8/SVneo cells and not in JEG-3 cells. This could be reason for the poor responsiveness of STAT3 responsive genes like mucin 1 (MUC1) in HTR-8/SVneo cells and not in JEG-3 cells. Further, microarray analysis of the IL-11 treated cells revealed differential responsiveness of JEG-3 as compared to HTR-8/SVneo cells. Several family of genes like activator protein-1 (AP-1) transcription factors (Jun and Fos), mucin-type molecules, MMP23B etc showed enhanced expression in IL-11 treated JEG-3 cells while, there was no response or decrease in their expression in IL-11 treated HTR-8/SVneo cells. Expression of these molecules was confirmed by quantitative RT-PCR. In addition, HTR-8/SVneo cells also showed a significant decrease in the expression of MMP2, MMP3 and MMP9 upon IL-11 treatment. Hence, IL-11 mediated differential activation of signaling and expression of effector molecules is responsible for the differential invasive response of JEG-3 and HTR-8/SVneo cells.
这项研究考察了 IL-11 介导的下游信号转导和效应分子表达的激活，以解决与 IL-11 介导的两种常用滋养层细胞模型（即 JEG-3 和 HTR-8/SVneo 细胞）侵袭性调节相关的争议。据报道，IL-11 增加了 JEG-3 细胞的侵袭性，而降低了 HTR-8/SVneo 细胞的侵袭性。同时对这两种细胞系进行的侵袭实验证实了上述发现。此外，HTR-8/SVneo 细胞的基础侵袭性高于 JEG-3 细胞。Western blot 显示，IL-11 在两种细胞系中均激活了 STAT3（tyr705）和 STAT1（tyr701）。然而，IL-11 在 JEG-3 细胞中激活了 ERK1/2 磷酸化，而在 HTR-8/SVneo 细胞中则抑制了该磷酸化。在 IL-11 处理后的 10 分钟内，p-STAT3（tyr705）定位于两种细胞的细胞核内，但在 HTR-8/SVneo 细胞中，蛋白激活 STAT1/3 抑制剂（PIAS1/3）和 p-STAT3（tyr705）的共定位增强，而在 JEG-3 细胞中则没有。这可能是 HTR-8/SVneo 细胞中 STAT3 反应基因（如粘蛋白 1（MUC1））反应不佳的原因，而 JEG-3 细胞中则没有。此外，IL-11 处理细胞的微阵列分析显示，与 HTR-8/SVneo 细胞相比，JEG-3 的反应不同。几个基因家族，如激活蛋白-1（AP-1）转录因子（Jun 和 Fos）、粘蛋白样分子、MMP23B 等，在 IL-11 处理的 JEG-3 细胞中表达增强，而在 IL-11 处理的 HTR-8/SVneo 细胞中则没有反应或表达减少。通过定量 RT-PCR 证实了这些分子的表达。此外，HTR-8/SVneo 细胞在接受 IL-11 处理后，MMP2、MMP3 和 MMP9 的表达也显著下降。因此，IL-11 介导的信号转导和效应分子表达的差异激活是 JEG-3 和 HTR-8/SVneo 细胞侵袭反应差异的原因。
