MicroRNA-129-1-3p attenuates autophagy-dependent cell death by targeting MCU in granulosa cells of laying hens under H2O2-induced oxidative stress.

The present study aimed to investigate the mechanism of microRNA-129-1-3p (miR-129-1-3p) in regulating hydrogen peroxide (H2O2)-induced autophagic death of chicken granulosa cell by targeting mitochondrial calcium uniporter (MCU). The results indicated that the exposure of hens' ovaries to H2O2 resulted in a significant elevation in reactive oxygen species (ROS) levels, as well as the apoptosis of granulosa cells and follicular atresia. This was accompanied by an upregulation of glucose-regulated protein 75 (GRP75), voltage-dependent anion-selective channel 1 (VDAC1), MCU, mitochondria fission factor (MFF), microtubule-associated protein 1 light chain 3 (LC3) I, and LC3II expression, and a downregulation of peroxisome proliferator-activated receptor gamma coactivator-1 alpha (PGC-1α) and mitofusin-2 (MFN2) expression. In hens' granulosa cells, a luciferase reporter assay confirmed that miR-129-1-3p directly regulates MCU. The induction of oxidative stress through H2O2 resulted in the activation of the permeability transition pore, an overload of calcium, depolarization of the mitochondrial membrane potential, dysfunction of mitochondria-associated endoplasmic reticulum membranes (MAMs), and ultimately, autophagic cell death. The overexpression of miR-129-1-3p effectively mitigated these H2O2-induced changes. Furthermore, miR-129-1-3p overexpression in granulosa cells prevented the alterations induced by H2O2 in the expression of key proteins that play crucial roles in maintaining the integrity of MAMs and regulating autophagy, such as GRP75, VDAC1, MFN2, PTEN-induced kinase 1 (Pink1), and parkin RBR E3 ubiquitin-protein ligase (Parkin). Together, these in vitro- and in vivo-based experiments suggest that miR-129-1-3p protects granulosa cells from oxidative stress-induced autophagic cell death by downregulating the MCU-mediated mitochondrial autophagy. miR-129-1-3p/MCU calcium signaling pathway may act as a new target to alleviate follicular atresia caused by oxidative stress in laying hens.

Expression and significance of microRNA-129-1 in colon cancer based on database mining / 中华消化杂志

Objective:To investigate the expression, regulation, potential mechanism and clinical significance of microRNA(miRNA)-129-1 in colon cancer.Methods:The changes of expression and methylation of miRNA-129-1 were analyzed from the methylation, mRNA expression and miRNA expression data of colon cancer in the cancer genome atlas (TCGA) database. The target genes of miRNA-129-1 were predicted from miRwalk 2.0 and TargetScan database. DAVID 6.7 online software was used for gene oncology and Kyoto encyclopedia of genes and genomes enrichment analysis. STRING database was used for protein-protein interaction analysis. TCGA data were applied again to analyze the differential expression and prognosis of key target genes of miRNA-129-1. Paired t test and independent sample t test were used for statistical analysis. The receiver operating characteristic curve (ROC) was used to evaluate the diagnostic value of miRNA-129-1 gene methylation in colon cancer. Kaplan-Meier method and log-rank test were used to analyze the effects of miRNA-129-1 expression on survival. Results:The sequence of miRNA-129-1 among different species was conserved. After all colon cancer samples, and control samples of TCGA database were analyzed, the results showed that compared with those of control samples, the expression of miRNA-129-1 decreased in cancer samples (0.98±0.81 vs. 5.74±0.59), and the methylation levels of cg04524088, cg04840800, cg11364290, cg20734982 and cg24044186 locus of miRNA-129-1 significantly decreased (0.321±0.130 vs. 0.563±0.051, 0.432±0.123 vs. 0.624±0.064, 0.475±0.153 vs. 0.768±0.033, 0.659±0.180 vs. 0.816±0.037 and 0.862±0.096 vs. 0.916±0.019, respectively) in colon cancer tissues, and the differences were all statistically significant ( t=14.95, 11.36, 9.39, 11.74, 5.32 and 3.47, all P<0.01). The results of ROC analysis showed that the methylation levels of the above five locus of miRNA-129-1 gene had high diagnostic efficiency in colon cancer (area under curve=0.946, 0.915, 0.950, 0.758 and 0.667, all P<0.01). The results of survival analysis indicated that low expression of miRNA-129-1 was associated with poor prognosis (hazard ratio ( HR)=0.55, P=0.018). The results of bioinformatics analysis demonstrated that the target genes of miRNA-129-1 were enriched in serine / threonine kinase receptor, mitogen-activated protein kinase and other functional gene clusters closely related to tumor, and there was a complex interaction network among the target genes proteins. The high expression of ephrin type-B receptor2 ( EPHB2) gene, a potential key target gene of miRNA-129-1, was associated with the short overall survival and disease-free survival time ( HR=1.9 and 1.6, both P<0.01). Conclusions:The expression and methylation of miRNA-129-1 play an important regulatory role in the development and development of colon cancer. The methylation of miRNA-129-1 has potential value in the diagnosis of colon cancer, and miRNA-129-1 is an influencing factor for the prognosis of patients with colon cancer. EPHB2 may be a potential key target gene of miRNA-129-1.

miR129-1 regulates protein phosphatase 1D protein expression under hypoxic conditions in non-small cell lung cancer cells harboring a TP53 mutation.

Protein phosphatase 1D (PPM1D), which functions as an oncogene, is a known target of the tumor suppressor p53 and is involved in p53-regulated genomic surveillance mechanisms. PPM1D dephosphorylates both p53 and its ubiquitin ligase mouse double minute 2 homolog, as well as the RNA-binding protein (RBM)38, which turns RBM38 from an inducer to inhibitor of TP53 translation. In addition, RBM38 induces PPM1D translation. Hence, the PPM1D-RBM38-p53 axis is important in maintaining genomic integrity and is often altered during tumorigenesis. TP53, which encodes p53, is deleted or mutated in >50% of cancer types, including lung cancer. Mutant p53 has been revealed to complex with hypoxia-inducible factor 1α (HIF1α) and upregulate transcription of pro-metastatic genes. However, the mechanism underlying the action of the PPM1D-RBM38-p53 axis in the context of mutant p53 under normoxic and hypoxic conditions is yet to be elucidated. In the present study, using non-small cell lung cancer (NSCLC) cell lines harboring wild-type (A549 cells) or hot-spot mutant (NCI-H1770 and R249WΔ-TP53-A549 cells) TP53, it was demonstrated that in cells harboring mutant p53, RBM38 was not the primary regulator of PPM1D translation under hypoxic conditions. Knockdown of RBM38 in TP53 mutant cells did not affect the PPM1D protein expression under hypoxic conditions. Instead, in NCI-H1770 cells maintained under normoxic conditions, PPM1D was revealed as a target of micro RNA (miR)-129-1-3p, a known tumor suppressor in lung cancer. Hypoxia resulted in the downregulation of miR-129-1-3p expression, and thus, in the downregulation of PPM1D messenger RNA (mRNA) translation. In NCI-H1770 cells grown under hypoxic conditions, the transient transfection of miR-129-1-3p mimic, and not control mimic, repressed the expression of a reporter containing wild-type, but not miR-129-1-3p binding mutant, of the PPM1D 3'-untranslated region (UTR). Analysis of NSCLC cell lines from the Broad Institute Cancer Cell Encyclopedia and patients with NSCLC from The Cancer Genome Atlas dataset revealed significant co-occurrence of PPM1D/RBM38 and PPM1D/HIF1A mutations. However, there was no significant difference in the overall survival of patients with NSCLC with or without genomic alterations in TP53, RBM38, PPM1D and HIF1A. In summary, the current study demonstrated hypoxia-dependent miR-129-1-3p-mediated regulation of PPM1D protein expression in NSCLC cell line harboring mutant TP53.

MicroRNA-129-1-3p regulates cyclic stretch-induced endothelial progenitor cell differentiation by targeting Runx2.

Endothelial progenitor cells (EPCs) are vital to the recovery of endothelial function and maintenance of vascular homeostasis. EPCs mobilize to sites of vessel injury and differentiate into mature endothelial cells (ECs). Locally mobilized EPCs are exposed to cyclic stretch caused by blood flow, which is important for EPC differentiation. MicroRNAs (miRNAs) have emerged as key regulators of several cellular processes. However, the role of miRNAs in cyclic stretch-induced EPC differentiation remains unclear. Here, we investigate the effects of microRNA-129-1-3p (miR-129-1-3p) and its novel target Runt-related transcription factor 2 (Runx2) on EPC differentiation induced by cyclic stretch. Bone marrow-derived EPCs were exposed to cyclic stretch with a magnitude of 5% (which mimics physiological mechanical stress) at a constant frequency of 1.25 Hz for 24 hours. The results from a miRNA array revealed that cyclic stretch significantly decreased miR-129-1-3p expression. Furthermore, we found that downregulation of miR-129-1-3p during cyclic stretch-induced EPC differentiation toward ECs. Meanwhile, expression of Runx2, a putative target gene of miR-129-1-3p, was increased as a result of cyclic stretch. A 3'UTR reporter assay validated Runx2 as a direct target of miR-129-1-3p. Furthermore, small interfering RNA (siRNA)-mediated knockdown of Runx2 inhibited EPC differentiation into ECs and attenuated EPC tube formation via modulation of vascular endothelial growth factor (VEGF) secretion from EPCs in vitro. Our findings demonstrated that cyclic stretch suppresses miR-129-1-3p expression, which in turn activates Runx2 and VEGF to promote endothelial differentiation of EPCs and angiogenesis. Therefore, targeting miR-129-1-3p and Runx2 may be a potential therapeutic strategy for treating vessel injury.