MiR-429 improved the hypoxia tolerance of human amniotic cells by targeting HIF-1α

Hypoxia inducible factor-1α related mechanism and TCM intervention in process of early fracture healing

As a common clinical disease, fracture is often accompanied by pain, swelling, bleeding as well as other symptoms and has a high disability rate, even threatening life, seriously endangering patients' physical and psychological health and quality of life. Medical practitioners take many strategies for the treatment of fracture healing, including Traditional Chinese Medicine (TCM). In the early stage of fracture healing, the local fracture is often in a state of hypoxia, accompanied by the expression of hypoxia inducible factor-1α (HIF-1α), which is beneficial to wound healing. Through literature mining, we thought that hypoxia, HIF-1α and downstream factors affected the mechanism of fracture healing, as well as dominated this process. Therefore, we reviewed the local characteristics and related signaling pathways involved in the fracture healing process and summarized the intervention of TCM on these mechanisms, in order to inspirit the new strategy for fracture healing, as well as elaborate on the possible principles of TCM in treating fractures based on the HIF molecular mechanism.

HIF-1-Induced hsa-miR-429: Understanding Its Direct Targets as the Key to Developing Cancer Diagnostics and Therapies

MicroRNAs (miRNAs) play a critical role in the regulation of mRNA stability and translation. In spite of our present knowledge on the mechanisms of mRNA regulation by miRNAs, the utilization and translation of these ncRNAs into clinical applications have been problematic. Using hsa-miR-429 as an example, we discuss the limitations encountered in the development of efficient miRNA-related therapies and diagnostic approaches. The miR-200 family members, which include hsa-miR-429, have been shown to be dysregulated in different types of cancer. Although these miR-200 family members have been shown to function in suppressing epithelial-to-mesenchymal transition, tumor metastasis, and chemoresistance, the experimental results have often been contradictory. These complications involve not only the complex networks involving these noncoding RNAs, but also the problem of identifying false positives. To overcome these limitations, a more comprehensive research strategy is needed to increase our understanding of the mechanisms underlying their biological role in mRNA regulation. Here, we provide a literature analysis of the verified hsa-miR-429 targets in various human research models. A meta-analysis of this work is presented to provide better insights into the role of hsa-miR-429 in cancer diagnosis and any potential therapeutic approach.

Estradiol mediates the interaction of LINC01541 and miR-429 to promote angiogenesis of G1/G2 endometrioid adenocarcinoma in-vitro: A pilot study

Background

Endometrioid adenocarcinoma (EAC) is the most common subtype of endometrial cancer (EC) and is an estrogen-related cancer. In this study, we sought to investigate the expressions and mechanism of action of 17β-estradiol (E2) and long noncoding RNA (lncRNA) LINC01541 in G1/G2 EAC samples.

Methods

The expressions of estrogen receptor β (ESR2), LINC01541, miR-200s, and VEGFA were evaluated using real-time PCR in human EAC tissues (n = 8) and adjacent normal tissues (n = 8). Two EC cell lines (Ishikawa and RL95-2) were selected for validation in vitro. Bioinformatics analyses and luciferase reporter analyses were performed to verify potential binding sites. qRT-PCR, Western blot, and CCK-8 were used to identify the regulatory mechanisms of related genes in cell biological behavior.

Results

Compared with adjacent normal tissues, LINC01541 and miR-200s family (except miR-200c) were highly expressed in EAC tissues (n=8), while ESR2 and VEGFA were lowly expressed in EAC tissues (* P < 0.05; ** P < 0.01). In vitro: E2 inhibited the expression of LINC01541 and miR-429 in both cell lines, and estrogen antagonist (PHTPP) could reverse this effect, in addition, PHTPP could promote the proliferation of these two cancer cells, cell transfection LINC01541 also had this effect after overexpression of plasmid and miR-429 mimic. E2 promotes the expression of VEGFA in both cell lines, and PHTPP can also reverse this effect. LINC01541 interacts with miR-429 to promote the expression of each other, and both inhibit the synthesis of VEGFA in EAC cells after overexpression. Through the double validation of bioinformatics analysis and dual fluorescein reporter gene, it was confirmed that miR-429 targets the regulation of VEGFA expression (* P < 0.05; ** P < 0.01).

Conclusion

E2 promotes the synthesis of VEGFA by altering the expression levels of LINC01541 and miR-429 in EAC, thereby affecting the angiogenesis process of EAC. Also, E2-mediated LINC01541/miR-429 expression may affect cell migration in EAC. In addition, we identified a reciprocal promotion between LINC01541 and miR-429.

IGFBP1 inhibits the invasion, migration, and apoptosis of HTR-8/SVneo trophoblast cells in preeclampsia

OBJECTIVE

To investigate the effects and underlying mechanisms of IGFBP1 on the biological functions of trophoblasts in simulated preeclampsia.

METHODS

IGFBP1 expression in placenta was determined by immunohistochemistry. HTR-8/SVneo cells were stimulated with/without IGFBP1-overexpression and hypoxia-reoxygenation, and the proliferation, invasion, migration, and apoptosis were detected by CCK8, transwell, and flow cytometry, respectively.

RESULTS

IGFBP1 expression was increased in placenta of preeclampsia. IGFBP1 overexpression inhibited proliferation, invasion, migration, and apoptosis of HTR-8/SVneo cells and induced MMP-26 expression with/without hypoxia-reoxygenation challenge.

CONCLUSION

IGFBP1 affects biological functions of trophoblasts, and it may play a role in pathophysiology of preeclampsia by inducing MMP-26.

[Inhibitory effect of miR-429 on expressions of ZO-1, Occludin, and Claudin-5 proteins to improve the permeability of blood spinal cord barrier in vitro]

OBJECTIVE

To explore the feasibility and mechanism of inhibiting miR-429 to improve the permeability of the blood spinal cord barrier (BSCB) in vitro, and provide a new gene therapy target for enhancing the spinal cord microenvironment.

METHODS

First, the immortalized human brain microvascular endothelial cell line (hCMEC/D3) was transfected with the anti-miR-429 antagonist (antagomiR-429) and its negative control (antagomiR-429-NC), respectively. The miR-429 expression of hCMEC/D3 cells was observed by fluorescence microscopy and real-time fluorescence quantitative PCR to verify the transfection efficiency of antagomiR-429. Then the effect of miR-429 on BSCB permeability was observed in vitro. The experiment was divided into 4 groups. The blank control group (group A) was constructed of normal hCMEC/D3 cells and Ha-sc cells to prepare the BSCB model, the hypoxia-induced group (group B), the hypoxia-induced+antagomiR-429-NC group (group C), and the hypoxia-induced+antagomiR-429 group (group D) were constructed of normal, antagomiR-429-NC transfected, and antagomiR-429 transfected hCMEC/D3 cells and Ha-sc cells to prepare the BSCB models and hypoxia treatment for 12 hours. The permeability of BSCB in vitro was measured by horseradish peroxidase (HRP) permeability. Real-time fluorescence quantitative PCR, Western blot, and immunofluorescence staining were used to observe the expressions of ZO-1, Occludin, and Claudin-5.

RESULTS

The antagomiR-429 and antagomiR-429-NC were successfully transfected into hCMEC/D3 cells under a fluorescence microscope, and the transfection efficiency was about 90%. Real-time fluorescence quantitative PCR results showed that the relative expression of miR-429 in antagomiR-429 group was 0.109±0.013, which was significantly lower than that of antagomiR-429-NC group (0.956±0.004, P<0.05). HRP permeability measurement, real-time fluorescence quantitative PCR, and Western blot results showed that the HRP permeability of groups B and C were significantly higher than those of groups A and D ( P<0.05), and the relative expressions of ZO-1, Occludin, and Claudin-5 proteins and mRNAs were significantly lower in groups B and C than in groups A and D ( P<0.05) and in group D than in group A ( P<0.05); there was no significant difference between groups B and C ( P>0.05). Immunofluorescence staining showed that the immunofluorescence of ZO-1, Occudin, and Claudin-5 at the cell membrane boundary in group D were stronger than those in groups B and C, but not as strong as that in group A.

CONCLUSION

Inhibition of miR-429 expression can promote the expressions of ZO-1, Occludin, and Claudin-5 proteins in microvascular endothelial cells, thereby improving the increased permeability of BSCB due to hypoxia.

Aberrant hydroxymethylation of ANGPTL4 is associated with selective intrauterine growth restriction in monochorionic twin pregnancies

Selective intrauterine growth restriction (sIUGR) is a severe complication in monochorionic (MC) twin pregnancies, and it carries increased risks of poor prognosis. Current data suggest that vascular anastomoses and unequal placental sharing may be the key contributor to discordant foetal growth. While MC twins derive from a single zygote and have almost identical genetic information, the precise mechanisms remain unknown. DNA hydroxymethylation is a newly discovered epigenetic feature associated with gene regulation and modification. Here, we investigate discordant hydroxymethylation patterns between two placental shares of sIUGR and analyse the potential role of aberrant hydroxymethylation of angiopoietin-like 4 (ANGPTL4) in placental dysplasia. Hydroxymethylation DNA immunoprecipitation (hMeDIP)-chip and mRNA sequencing were performed to identify hydroxymethylation-associated genes. Real-time qPCR, western blotting, and immunohistochemistry were used to confirm ANGPTL4 expression. The mechanisms regulating ANGPTL4 were investigated by cell migration assay, invasion assay, viability assay, and apoptotic ratio assays, western blotting and hMeDIP-qPCR. Decreased ANGPTL4 was detected in the smaller placental shares of sIUGR. ANGPTL4 knockdown suppressed trophoblast invasiveness and migration, which possibly occurred through hypoxia inducible factor 1α (HIF-1α) and HIF-1 signalling pathway. Hypoxia leads to aberrant expression of ANGPTL4 and HIF-1α, positively correlated with their aberrant hydroxymethylation levels in promoter regions. Aberrant hydroxymethylation of ANGPTL4 may contribute to placental impairment by the HIF-1 signalling pathway in smaller placental shares of sIUGR.

miR-495 promotes apoptosis and inhibits proliferation in endometrial cells via targeting PIK3R1

Endometrial cancer (EC) is a huge threat to women's health. The aims of this study were to investigate the role of microRNA (miR)-495 in the proliferation and apoptosis of EC cells in vitro. Reverse transcription-quantitative polymerase chain reaction (RT-qPCR) was performed to detect the mRNA levels. In addition, dual-luciferase reporter assay was used to verified that PIK3R1 was a target of miR-495. After transfection with miR-495 mimics, Cell Counting Kit 8 (CCK-8) assay was performed to evaluate the cell viability of EC cells. The protein expression of PIK3R1, vascular endothelial growth factor (VEGF), Bcl-2, Bax, caspase 3 after transfection was analyzed using western blotting. Furthermore, cell apoptosis rate of EC cells was evaluated by flow cytometry. These results showed that miR-495 was significantly down-regulated in tumor tissues compared with the adjacent normal tissues, while PIK3R1 was up-regulated. The proliferation of the EC cells that were transfected with miR-495 mimics was markedly inhibited, and apoptosis was significantly promoted. In addition, downregulated expression of PIK3R1, Bcl-2, VEGF expression and upregulated expression of Bax and caspase 3 expression were observed after transfected with miR-495 mimic. Together these findings indicated that miR-495 acts as a tumor suppressor gene by directly targeting PIK3R1 at the post-transcriptional level in EC cells in vitro.