LncRNA MALAT1 regulates trophoblast cells migration and invasion via miR-206/IGF-1 axis

Preeclampsia (PE) is a pregnancy-specific syndrome that substantially leads to maternal and fetal mortality. Multiple factors contribute to the disease, but the exact pathogenesis still remains elusive. Here we explored the roles of lncRNA MALAT1 and miR-206 in PE. qRT-PCR was applied to measure mRNA levels of MALAT1 and miR-206 in the placenta of PE patients. Scratch wound healing assay and transwell invasion assay were conducted to test the effects of MALAT1 and miR-206 on migration and invasion of trophoblast cells. In addition, we validated MALAT1/miR-206 and miR-206/IGF-1 interactions with dual luciferase reporter assay. Western bot was used to detect protein expressions of IGF-1, p-PI3K, PI3K, p-Akt and Akt. We found that MALAT1 was decreased but miR-206 was increased in the placenta of patients with PE. Inhibition of MALAT1, knockdown IGF-1, or miR-206 mimics suppressed the trophoblast cells migration and invasion, while overexpression of MALAT1, IGF-1 or miR-206 inhibitors exhibited opposite effects. Further, miR-206 was confirmed as a direct target of MALAT1. Besides, miR-206 inhibited IGF-1 expression by directly binding to the 3'UTR. Mechanistically, our study demonstrated that MALAT1 regulates IGF-1/PI3K/Akt signaling via miR-206. Together, these results suggest that MALAT1 and miR-206 play important roles in PE. MALAT1 regulates miR-206/IGF-1 axis, thereby modulating trophoblast cells migration and invasion through PI3K/Akt signal pathway. These results show light on the underlying mechanisms of PE and provide potential targets for PE therapy.Abbreviations: PE: Preeclampsia; lncRNA: Long-non-coding RNA; MALAT1: Metastasis-associated lung adenocarcinoma transcript 1; IGF-1: Insulin-like growth factor 1; PI3k: Phosphatidylinositol-4, 5-bisphosphate 3-kinase; Akt: Protein kinase B; GAPDH: Glyceraldehyde 3-phosphate dehydrogenase; qRT-PCR: Quantitative Reverse Transcription polymerase chain reaction; shRNA: Short hairpin RNA; siRNA: Small interfering RNA; EMT: Epithelial-mesenchymal transition.