MiR-424-5p Inhibits Proliferation, Migration, Invasion and Angiogenesis of the HTR-8/SVneo Cells Through Targeting LRP6 Mediated β-catenin

The aim of this study was to investigate the effects of miR-424-5p on biological behaviors and angiogenesis of the HTR-8/SVneo Cells. Our study included 60 parturient women, which were divided into an PA group (placenta accreta, n = 30) and a normal group (normal placenta, n = 30). QPCR was used to measure the expression of miR-424-5p in placental tissues. The effects of the miR-424-5p mimic on proliferation, migration, and invasion of human HTR-8/SVneo cells and angiogenesis were analyzed. The potential modulated relationship between miR-424-5p and low-density lipoprotein receptor-related protein-6 (LRP6) was demonstrated by luciferase assay. The expression of LRP6, β-catenin, matrix metalloproteinase-2 (MMP-2), placental growth factor (PGF) and vascular endothelial growth factor (VEGF) were measured by qPCR and Western blot assays. The expression of miR-424-5p in the PA group was significantly decreased than that in the normal group. The expression of miR-424-5p has negative correlation with blood loss. Upregulation of miR-424-5p significantly suppressed the cell proliferation, migration, and invasion of HTR-8/SVneo cells in vitro, as well as the tube formation of human umbilical vein endothelial cells (HUVECs). The luciferase assay demonstrated that LRP6 was a target of miR-424-5p. The expression of LRP6, β-catenin, MMP-2, PGF and VEGF were also decreased with upregulation of miR-424-5p (p < 0.05). The inhibitory effects of miR-424-5p on HTR-8/SVneo cells and angiogenesis were enhanced by downregulation of LRP6, but were reversed by upregulation of LRP6. The present study suggests that downregulation of miR-424-5p is related to the occurrence of PA. Enhancing miR-424-5p inhibits proliferation, migration, invasion and angiogenesis of the HTR-8/SVneo cells through targeting LRP6 mediated β-catenin, providing more insights about PA.

Genomic Differences between Spontaneous versus Indicated Extreme Preterm Birth

OBJECTIVE

 Extremely preterm infants are at high risk of neonatal mortality and morbidity. Extreme preterm birth (PTB) may result from spontaneous preterm labor or preterm premature rupture of membranes or may be indicated due to preeclampsia, eclampsia, hypertension, or other causes. Our objective was to identify single nucleotide polymorphisms (SNPs) and biological pathways associated with spontaneous versus indicated extreme PTB using the neonatal genome.

STUDY DESIGN

 We evaluated 523 spontaneous births and 134 indicated births weighing 401 to 1,000 g at birth from the Eunice Kennedy Shriver National Institute of Child Health and Human Development Neonatal Research Network's Genomics dataset by genome-wide association study (GWAS) and pathway analysis. The TOLSURF cohort was used to replicate the results.

RESULTS

 In the NRN GWAS, no statistically significant results were found, although the Manhattan plot showed one almost significant peak (rs60854043 on chromosome 14 at p = 1.03E-07) along with many other modest peaks at p = 1-9E-06, for a total of 15 suggestive associations at this locus. In the NRN pathway analysis, multiple pathways were identified, with the most significant being "GO_mf:go_low_density_lipoprotein_particle_receptor_activity" at p = 1.14E-06. However, these results could not be replicated in the TOLSURF cohort.

CONCLUSION

 Genomic differences are seen between infants born by spontaneous versus indicated extreme PTB. Due to the limited sample size, there is a need for larger studies.

KEY POINTS

· Genomic differences are seen between infants born by spontaneous versus indicated very PTB.. · Future studies with large sample sizes evaluating extreme PTB are necessary.. · Spontaneous PTB is more common than indicated extreme PTB..

MicroRNA-513c-5p is involved in the pathogenesis of preeclampsia by regulating of low-density lipoprotein receptor-associated protein 6

Background

Preeclampsia (PE) is a major cause of maternal and perinatal morbidity and mortality. Studies on the role of microRNAs (miRNAs), in the pathogenesis of PE through their effects on trophoblast function have been reported, but roles for some miRNAs including miR-513c-5p, have not been identified. We aimed to evaluate potential miRNA candidates that regulate the LRP6 mRNAand to elucidate the possible mechanism in PE. Potential miRNAs were selected by bioinformatics analysis, PCR of placenta tissues and dual luciferase reporter assay of HTR-8/SVneo cells.

Methods

A bioinformatics analysis (Gene Expression Omnibus, GEO; miRWalk) was performed to screen the possible miRNAs that participate in the pathology of PE. Placentas from patients with PE and women with a normal pregnancy were collected to detect the expression of predicted miRNAs by RT-qPCR. A dual luciferase reporter assay was used to test the binding of the potential miRNAs to LRP6. The effects of miR-513c-5p on the biological functions of HTR-8/SVneo cells were further evaluated by performing EdU staining, flow cytometry, wound healing assays and Transwell assays.

Results

GEO and miRWalk predicted 16 miRNAs that might target LRP6. Hsa-miR-371a-5p, hsa-miR-513c-5p, hsa-miR-126-3p, hsa-miR-145-5p, hsa-miR-193b-5p and hsa-miR-296-5p were 6 miRNAs upregulated in the PE placenta. LRP6 was downregulated in patients with PE compared to normal women. miR-513c-5p mimics inhibited LRP6 expression in HTR-8/SVneo cells, and LRP6 is the target gene of miR-513c-5p. miR-513c-5p mimics also inhibited invasion, migration and proliferation of HTR-8/SVneo cells but promoted their apoptosis.

Conclusions

Our study reveals that overexpression of placenta miR-513c-5p is involved in PE by regulating the biological functions of trophoblasts through the inhibition of LRP6.

Hsa_circ_0074371 Regulates Proliferation, Apoptosis, Migration, and Invasion via the miR-582-3p/LRP6 Axis in Trophoblast Cells

Fetal growth restriction (FGR) ranks second among causes of perinatal death. Circular RNA hsa_circ_0074371 (hsa_circ_0074371) is reported to be downregulated in FGR placentae. However, the role and regulatory mechanism of hsa_circ_0074371 in FGR pathogenesis are indistinct. Expression of hsa_circ_0074371, microRNA (miR)-582-3p, and low-density lipoprotein receptor-related protein 6 (LRP6) mRNA in FGR placentae and trophoblast cells (HTR-8/SVneo) was detected by quantitative real-time polymerase chain reaction (qRT-PCR). The relationship between hsa_circ_0074371 or LRP6 and miR-582-3p was verified by dual-luciferase reporter and/or RNA immunoprecipitation (RIP), RNA pull-down assays. The proliferation, cell cycle progression, apoptosis, migration, and invasion of HTR-8/SVneo cells were evaluated by Cell Counting Kit-8 (CCK-8), flow cytometry, wound healing, or transwell assays. Caspase3 activity was analyzed with a commercial kit. The protein levels of c-myc, cyclinD1, matrix metalloproteinase (MMP) 2, MMP9, and LRP6 were examined by western blotting. We observed that hsa_circ_0074371 and LRP6 were downregulated while miR-582-3p was upregulated in FGR placentae and HTR-8/SVneo cells. Hsa_circ_0074371 modulated LRP6 expression via sponging miR-582-3p. Hsa_circ_0074371 knockdown induced cell cycle arrest, apoptosis, and inhibited cell proliferation, migration, and invasion in HTR-8/SVneo cells. MiR-582-3p inhibitor reversed hsa_circ_0074371 silencing me on proliferation, migration, and invasion of HTR-8/SVneo cells. LRP6 overexpression overturned the inhibitory effect of miR-582-3p mimic on proliferation, migration, and invasion of HTR-8/SVneo cells. In conclusion, hsa_circ_0074371 downregulation inhibited proliferation, migration, and invasion of trophoblast cells via sponging miR-582-3p and decreasing LRP6 expression, providing a new mechanism related to FGR pathogenesis.

LRP6 regulates Rab7-mediated autophagy through the Wnt/β-catenin pathway to modulate trophoblast cell migration and invasion

Pre-eclampsia is a common complication during pregnancy; however, the underlying mechanisms of the crosstalk between low-density lipoprotein receptor-related protein 6 (LRP6) and autophagy in trophoblast cells are still not fully explored. Messenger RNA (mRNA) and protein levels of LRP6, beclin 1, Unc-51-like autophagy activating kinase 1 (ULK1), p62, vimentin, matrix metallopeptidase-9 (MMP-9), β-catenin, c-Myc, and Rab7, as well as the ratio of LC3-II/LC3-I, were analysed by quantitative real-time polymerase chain reaction or Western blot analysis, respectively. An MTT assay was used to measure cell growth, and transwell and wound healing assays were carried out to evaluate the invasion and migration abilities of the trophoblasts used. An immunofluorescence assay was used to measure LC3. The mRFP-GFP-LC3 tandem fluorescence assay was applied to detect autophagic flow. LRP6 overexpression was achieved by constructing pcDNA3.1-LRP6 vectors. LRP6 was expressed at low levels in HTR-8/SVneo cells under hypoxia/reoxygenation (H/R) conditions. H/R inhibited the activation of autophagy. LRP6 overexpression promoted cell proliferation and activated autophagy, which led to the upregulation of beclin 1 and ULK1, as well as the ratio of LC3-II/LC3-I and the downregulation of p62. Furthermore, LRP6 overexpression elevated the migration and invasion abilities of the indicated cells and increased vimentin and MMP-9 expression levels. Furthermore, LRP6 upregulated Rab7 and activated autophagy through the Wnt/β-catenin pathway. The late autophagy inhibitor bafilomycin A1 (Baf-A1) and the Wnt/β-catenin pathway inhibitor PKF115-584 reversed the effects of LRP6 on trophoblast autophagy, migration and invasion. LRP6 promotes Rab7-mediated autophagy by activating the Wnt/β-catenin pathway, which leads to increasing migration and invasion of trophoblast cells. Our study paves a new avenue for clinical treatment, and LRP6 may serve as an essential target in pre-eclampsia.