Overexpressed miR-122-5p Promotes Cell Viability, Proliferation, Migration And Glycolysis Of Renal Cancer By Negatively Regulating PKM2

The Inhibition of Fibrosis and Inflammation in Obstructive Kidney Injury via the miR-122-5p/SOX2 Axis Using USC-Exos

Background: Fibrosis and inflammation due to ureteropelvic junction obstruction substantially contributes to poor renal function. Urine-derived stem-cell-derived exosomes (USC-Exos) have therapeutic effects through paracrine. Methods: In vitro, the effects of USC-Exos on the biological functions of HK-2 and human umbilical vein endothelial cells were tested. Cell inflammation and fibrosis were induced by transforming growth factor-β1 and interleukin-1β, and their anti-inflammatory and antifibrotic effects were observed after exogenous addition of USC-Exos. Through high-throughput sequencing of microRNA in USC-Exos, the pathways and key microRNAs were selected. Then, the antifibrotic and anti-inflammatory effects of exosomal miR-122-5p and target genes were verified. The role of the miR-122-5p/SOX2 axis in anti-inflammatory and antifibrotic effects was verified. In vivo, a rabbit model of partial unilateral ureteral obstruction (PUUO) was established. Magnetic resonance imaging recorded the volume of the renal pelvis after modeling, and renal tissue was pathologically analyzed. Results: We examined the role of USC-Exos and their miR-122-5p content in obstructive kidney injury. These Exos exhibit antifibrotic and anti-inflammatory activities. SOX2 is the hub gene in PUUO and negatively related to renal function. We confirmed the binding relationship between miR-122-5p and SOX2. The anti-inflammatory and antifibrotic effects of miR-122-5p were inhibited, indicating that miR-122-5p has anti-inflammatory and antifibrotic effects by inhibiting SOX2 expression. In vivo, the PUUO group showed typical obstructive kidney injury after modeling. After USC-Exo treatment, the shape of the renal pelvis shown a remarkable improvement, and inflammation and fibrosis decreased. Conclusions: We confirmed that miR-122-5p from USC-Exos targeting SOX2 is a new molecular target for postoperative recovery treatment of obstructive kidney injury.

Study on the Role and Mechanism of Exosomes Derived from Dental Pulp Stem Cells in Promoting Regeneration of Myelin Sheath in Rats with Sciatic Nerve Injury

The prognosis of peripheral nerve injury (PNI) is usually poor, and currently, there is no effective treatment for PNI. Studies have shown that exosomes derived from mesenchymal stem cells could promote nerve regeneration by optimizing the function of endogenous Schwann cells (SCs), while the mechanism is unclear. Autophagy, a highly conserved intracellular catabolic process responsible for maintaining cellular homeostasis, has been proved to be involved in the regulation of nerve repair after injury. We explored the effect of exosomes derived from dental pulp stem cells (DPSC-Exos) on the regeneration of myelin sheath in rats with sciatic nerve injury (SNI). In vitro and in vivo experiments were performed to clarify whether the effect of DPSC-Exos is associated with autophagy of SCs and to reveal the mechanism at the molecular level. Our results showed that the SCs of SNI rats exhibited the obvious autophagic characteristics, and the increase of P53 expression was an internal factor of autophagy. Our mechanism research indicated that DPSC-Exos could deliver miR-122-5p from DPSCs into SCs and suppressed the rapamycin (RAPA)-induced autophagy in SCs by inhibiting P53 expression. Rescue experiments showed that both the use of GW4869 and overexpression of exogenous P53 in SCs could reverse the inhibitory effect of DPSCs on the autophagy in SCs from co-culture system. In short, our study indicated that DPSC-Exos could promote the regeneration of the myelin sheath through suppressing the autophagy in SCs caused by PNI via miR-122-5p/P53 pathway; this provides researchers with another option for precise repair of PNI.

MicroRNA-122 in human cancers: from mechanistic to clinical perspectives

MicroRNAs (miRNAs) are endogenous short non-coding RNAs that can regulate the expression of target genes post-transcriptionally and interact with mRNA-coding genes. MiRNAs play vital roles in many biological functions, and abnormal miRNA expression has been linked to various illnesses, including cancer. Among the miRNAs, miR-122, miR-206, miR-21, miR-210, miR-223, and miR-424 have been extensively studied in various cancers. Although research in miRNAs has grown considerably over the last decade, much is yet to be discovered, especially regarding their role in cancer therapies. Several kinds of cancer have been linked to dysregulation and abnormal expression of miR-122, indicating that miR-122 may serve as a diagnostic and/or prognostic biomarker for human cancer. Consequently, in this review literature, miR-122 has been analyzed in numerous cancer types to sort out the function of cancer cells miR-122 and enhance patient response to standard therapy.

MiRNAs from serum-derived extracellular vesicles as biomarkers for uveal melanoma progression

Uveal melanoma (UM) is a rare type of malignancy that originates from melanocytes in the choroid, iris and the eye's ciliary body. Biomarkers for early detection and progression of UM, especially the molecular traits governing the development of metastasis, are still not available in clinical practice. One extensively studied components of liquid biopsies are extracellular vesicles. Due to their unique molecular cargo, they can contribute to early cancer development and at the same time carry markers for disease onset and progression. For characterisation of the miRNA profiles present in circulating serum-derived exosomes of patients with diagnosed primary and metastatic UM, we have analyzed the miRNA cargos using next-generation sequencing followed by RT-qPCR validation in a cohort of patients (control n = 20; primary n = 9; metastatic n = 11). Nine miRNAs differentiating these patient groups have been established. We show that hsa-miR-144-5p and hsa-miR-191-5p are the most promising biomarker candidates, allowing the categorization of patients into local and advanced UM. Additionally, the comparison of miRNA expression levels in exosomes derived from UM patients with those derived from healthy donors revealed that hsa-miR-191-5p, -223-3p, -483-5p, -203a has the potential to be used as an early marker for the presence of UM. This pilot study reveals that miRNAs extracted from circulating exosomes could be exploited as potential biomarkers in UM diagnosis and, more importantly, for indicating metastatic spread.

circRNA DENND1B inhibits tumorigenicity of clear cell renal cell carcinoma via miR-122-5p/TIMP2 axis

Clear cell renal cell carcinoma (ccRCC) is the most common type of renal cancers. However, circ_DENND1B has not been studied yet. GSE100186 dataset was used for the level analysis of circ_DENND1B. The quantitative real-time PCR was used to verify the expression of circ_DENND1B, microRNA-122-5p (miR-122-5p) and tissue inhibitor of metalloproteinases-2 (TIMP2) in ccRCC tissues and cells. Cell proliferation, migration, invasion and apoptosis were detected by colony formation assay, thymidine analog 5-ethynyl-2'-deoxyuridine assay, 3-(4,5-dimethylthiazol-2-y1)-2,5-diphenyl tetrazolium bromide, transwell and flow cytometry. The binding of miR-122-5p to circ_DENND1B/TIMP2 was investigated by dual-luciferase reporter assay. Finally, the role of circ_DENND1B in ccRCC was detected by tumorigenesis experiment in mice. circ_DENND1B was downregulated in ccRCC and circ_DENND1B overexpression suppressed the malignant behaviors of ccRCC cells. circ_DENND1B acted as a sponge of miR-122-5p. miR-122-5p upregulation reversed the effects of circ_DENND1B on cell proliferation, migration, invasion and apoptosis. TIMP2 was a target of miR-122-5p. Overexpression of circ_DENND1B regulated TIMP2 level by inhibiting miR-122-5p expression in ccRCC cells. circ_DENND1B overexpression inhibited the tumor growth of ccRCC in vivo. circ_DENND1B inhibited ccRCC cell progression by promoting TIMP2 expression by sponging miR-122-5p, suggesting that circ_DENND1B might be an effective therapeutic target for ccRCC.

Advances of Mesenchymal Stem Cells Released Extracellular Vesicles in Periodontal Bone Remodeling

Extracellular vesicles (EVs) are nanoparticles that include exosomes, microvesicles, and apoptotic bodies; they interact with target cell surface receptors and transport contents, including mRNA, proteins, and enzymes into the cytoplasm of target cells to function. The biological fingerprints of EVs practically mirror those of the parental cells they originated from. In the bone remodeling microenvironment, EVs could act on osteoblasts to regulate the bone formation, promote osteoclast differentiation, and regulate bone resorption. Therefore, there have been many attempts wherein EVs were used to achieve targeted therapy in bone-related diseases. Periodontitis, a common bacterial infectious disease, could cause severe alveolar bone resorption, resulting in tooth loss, whereas research on periodontal bone regeneration is also an urgent question. Therefore, EVs-related studies are important for periodontal bone remodeling. In this review, we summarize the current knowledge of mesenchymal stem cell-EVs involved in periodontal bone remodeling and explore the functional gene expression through a comparative analysis of transcriptomic content.

miR-122-5p regulates proliferation and apoptosis of chicken granulosa cells of hierarchal follicles by targeting MAPK3

Chicken follicles plays a crucial role in the reproductive performance, especially in laying period. Recently, miR-122-5p has been found to be differentially expressed in the ovaries of rats with polycystic ovary syndrome and normal rats, indicating the potential role of miR-122-5p in the development of granulosa cells (GCs). In present study, we found that miR-122-5p was highly expressed in chicken atrophic ovaries. Herein, we investigated its function on GC proliferation and apoptosis of chicken in vitro. We found that overexpression of miR-122-5p significantly inhibited proliferation and promoted apoptosis of GCs, whereas the opposite effects were detected in miR-122-5p knockdown GCs. Meanwhile, mitogen-activated protein kinase 3 (MAPK3) was confirmed as a new target gene of miR-122-5p by bioinformatics software prediction and the dual-luciferase reporter assay verification. Furthermore, after knockdown of MAPK3, the function of MAPK3 for GC proliferation and apoptosis was opposite to that of miR-122-5p. Collectively, our results indicated that miR-122-5p impeded chicken GC proliferation and promoted apoptosis through the post-transcriptional downregulation of MAPK3.

The long noncoding RNA MIR122HG is a precursor for miR-122-5p and negatively regulates the TAK1-induced innate immune response in teleost fish

Long noncoding RNAs (lncRNAs) are a diverse subset of RNA species of noncoding transcripts that are usually longer than 200 nt. However, the biological role and function of many lncRNAs have not been fully identified. It has been shown that one potential function of lncRNAs is to act as a precursor miRNA and promote the production of multiple miRNAs. However, the function of the miiuy croaker lncRNA MIR122HG has not been explored. In the present study, we show that this differentially expressed teleost fish lncRNA can act as the host gene of miR-122-5p, regulate its expression, and indirectly regulate the expression of potential inflammatory target protein transforming growth factor-β–activated kinase 1. We show that MIR122HG can negatively regulate the transforming growth factor-β–activated kinase 1–triggered NF-κB and interferon regulatory factor 3 signaling pathways and subsequently attenuate the innate immune response. In addition, MIR122HG can promote the replication of Siniperca chuatsi rhabdovirus and exacerbate the pathological effects caused by viral infection. We conclude that the study of lncRNA–miRNA–mRNA interaction through bioinformatics analysis or experimental-supported analysis can provide information for further elucidation of the functions of fish lncRNAs in innate immunity.

Radix Rehmannia Glutinosa inhibits the development of renal fibrosis by regulating miR-122-5p/PKM axis

OBJECTIVE

It is acknowledged that Radix Rehmanniae Praeparata (RR) can regulate hormone metabolism, reduce blood glucose, resist aging, help to sedate patients and promote diuresis. The study aims to investigate the mechanism of how RR influences the development of renal fibrosis by regulating the miR-122-5p/PKM axis.

METHODS

Unilateral ureteral obstruction (UUO) was applied to induce renal fibrosis in mice in vivo, and human tubular epithelial HK2 cells treated by transforming growth factor-β (TGF-β1) were used to induce renal fibrosis in vitro. Interleukin 6 (IL-6) and tumor necrosis factor-α (TNF-α) in mouse serum were detected by Enzyme-linked immunosorbent assay (ELISA); fibronectin (FN) and type I collagen (Col-I) in renal tissue were detected by Western blotting; serum creatinine (Cr) and blood urea nitrogen (BUN) were analyzed by kits. Hematoxylin-eosin (HE) staining and Masson staining were utilized to assess the degree of pathological damage and fibrosis. Cell viability and apoptosis in the in vitro model were detected by MTT and Flow cytometry. Dual-luciferase reporter assay was performed to determine intermolecular targeting relationships.

RESULTS

RR could inhibit IL-6 and TNF-α levels, decrease the levels of FN and Col-I and improve the renal function indexes (serum Cr and BUN) in UUO mice (all P<0.05). In addition, RR was able to promote the up-regulation of miR-122-5p expression in UUO mice in vivo (P<0.05). MiR-122-5p expression was down-regulated and PKM expression was up-regulated in HK2 cells treated with TGF-β1 (all P<0.05). RR inhibited renal fibrosis progression by regulating the miR-122-5p/PKM axis. Inhibition of miR-122-5p or overexpression of PKM could promote apoptosis of TGF-β1-treated HK2 cells, inhibit their viability, aggravate fibrosis, and attenuate the protective effect of RR on the cells. The protective effect of RR promoted by overexpression of miR-122-5p was partially counteracted by PKM.

CONCLUSION

RR can inhibit renal fibrosis progression by regulating the miR-122-5p/PKM axis.

Androgen Receptors Act as a Tumor Suppressor Gene to Suppress Hepatocellular Carcinoma Cells Progression via miR-122-5p/RABL6 Signaling

Hepatocellular carcinoma (HCC) is a malignant tumor with a high degree of malignancy and a poor prognosis. Androgen receptor (AR) has been reported to play important roles in the regulation of the progression of HCC, but the underlying mechanisms of how AR regulates HCC initiation, progression, metastasis, and chemotherapy resistance still need further study. Our study found that AR could act as a tumor suppression gene to suppress HCC cells invasion and migration capacities via miR-122-5p/RABL6 signaling, and the mechanism study further confirmed that miR-122-5p could suppress the expression of RABL6 to influence HCC cells progression by directly targeting the 3'UTR of the mRNA of RABL6. The preclinical study using an in vivo mouse model with orthotopic xenografts of HCC cells confirmed the in vitro data, and the clinical data gotten from online databases based on TCGA samples also confirmed the linkage of AR/miR-122-5p/RABL6 signaling to the HCC progression. Together, these findings suggest that AR could suppress HCC invasion and migration capacities via miR-122-5p/RABL6 signaling, and targeting this newly explored signaling may help us find new therapeutic targets for better treatment of HCC.

MiR-122 radiosensitize hepatocellular carcinoma cells by suppressing cyclin G1

PURPOSE

Emerging evidence has shown that radiotherapy is an effective treatment for hepatocellular carcinoma (HCC), Micro(mi)RNAs are involved in regulating radiosensitivity in many cancers. MiR-122 accounts for approximately 70% of all cloned miRNAs in the liver, but there are few reports about whether it is involved in regulating of radiosensitivity in HCC cells.

MATERIALS AND METHODS

HCC cells (HepG2 and Huh7) overexpressing miR-122 were constructed by transfecting them with lentiviral-miR-122. Then, their proliferation ability was analyzed by the MTT, and colony formation assays and a xenograft tumor model was used to detect their radiosensitivity. The expression of cyclin G1 mRNA and protein was detected by the quantitative real-time polymerase chain reaction and western blotting, respectively.

RESULTS

Overexpression of miR-122 inhibited the proliferation of, and radiosensitized HCC cells. Cyclin G1 mRNA and protein level were suppressed in HepG2 tumors overexpression miR-122.

CONCLUSION

MiR-122 may be useful as a potential radiosensitizer for HCC, and its mechanism is related to the regulation of cyclin G1.

A Glycolysis-Based Long Non-coding RNA Signature Accurately Predicts Prognosis in Renal Carcinoma Patients

Background

The prognosis of renal cell carcinoma (RCC) varies greatly among different risk groups, and the traditional indicators have limited effect in the identification of risk grade in patients with RCC. The purpose of our study is to explore a glycolysis-based long non-coding RNAs (lncRNAs) signature and verify its potential clinical significance in prognostic prediction of RCC patients.

Methods

In this study, RNA data and clinical information were downloaded from The Cancer Genome Atlas (TCGA) database. Univariate and multivariate cox regression displayed six significantly related lncRNAs (AC124854.1, AC078778.1, EMX2OS, DLGAP1-AS2, AC084876.1, and AC026401.3) which were utilized in construction of risk score by a formula. The accuracy of risk score was verified by a series of statistical methods such as receiver operating characteristic (ROC) curves, nomogram and Kaplan-Meier curves. Its potential clinical significance was excavated by gene enrichment analysis.

Results

Kaplan-Meier curves and ROC curves showed reliability of the risk score to predict the prognosis of RCC patients. Stratification analysis indicated that the risk score was independent predictor compare to other traditional clinical parameters. The clinical nomogram showed highly rigorous with index of 0.73 and precisely predicted 1-, 3-, and 5-year survival time of RCC patients. Kyoto Encyclopedia of Genes and Genomes (KEGG) and Gene set enrichment analysis (GSEA) depicted the top ten correlated pathways in both high-risk group and low-risk group. There are 6 lncRNAs and 25 related mRNAs including 36 lncRNA-mRNA links in lncRNA-mRNA co-expression network.

Conclusion

This research demonstrated that glycolysis-based lncRNAs possessed an important value in survival prediction of RCC patients, which would be a potential target for future treatment.

PTBP1-targeting microRNAs regulate cancer-specific energy metabolism through the modulation of PKM1/M2 splicing

Understanding of the microRNAs (miRNAs) regulatory system has become indispensable for physiological/oncological research. Tissue and organ specificities are key features of miRNAs that should be accounted for in cancer research. Further, cancer-specific energy metabolism, referred to as the Warburg effect, has been positioned as a key cancer feature. Enhancement of the glycolysis pathway in cancer cells is what primarily characterizes the Warburg effect. Pyruvate kinase M1/2 (PKM1/2) are key molecules of the complex glycolytic system; their distribution is organ-specific. In fact, PKM2 overexpression has been detected in various cancer cells. PKM isoforms are generated by alternative splicing by heterogeneous nuclear ribonucleoproteins. In addition, polypyrimidine tract-binding protein 1 (PTBP1) is essential for the production of PKM2 in cancer cells. Recently, several studies focusing on non-coding RNA elucidated PTBP1 or PKM2 regulatory mechanisms, including control by miRNAs, and their association with cancer. In this review, we discuss the strong relationship between the organ-specific distribution of miRNAs and the expression of PKM in the context of PTBP1 gene regulation. Moreover, we focus on the impact of PTBP1-targeting miRNA dysregulation on the Warburg effect.

Regulation of Autophagy by Glycolysis in Cancer

Autophagy is a critical cellular process that generally protects cells and organisms from harsh environment, including limitations in adenosine triphosphate (ATP) availability or a lack of essential nutrients. Metabolic reprogramming, a hallmark of cancer, has recently gained interest in the area of cancer therapy. It is well known that cancer cells prefer to utilize glycolysis rather than oxidative phosphorylation (OXPHOS) as their major energy source to rapidly generate ATP even in aerobic environment called the Warburg effect. Both autophagy and glycolysis play essential roles in pathological processes of cancer. A mechanism of metabolic changes to drive tumor progression is its ability to regulate autophagy. This review will elucidate the role and the mechanism of glycolysis in regulating autophagy during tumor growth. Indeed, understanding how glycolysis can modulate cellular autophagy will enable more effective combinatorial therapeutic strategies.

Human Periodontal Ligament Stem Cell-Derived Exosomes Promote Bone Regeneration by Altering MicroRNA Profiles

The role and underlying mechanism of exosomes derived from human periodontal ligament stem cells (PDLSC) in osteogenesis are unclear. In the present study, we identified the exosomes derived from PDLSCs and found that osteogenic induction can enhance the osteogenic ability of PDLSC-derived exosomes in promoting the osteogenic differentiation of rat bone marrow stem cells (BMSCs). To investigate the underlying mechanism, we analyzed the exosomal miRNA expression profiles of undifferentiated and osteogenic differentiated PDLSCs by RNA sequencing. The results showed that seventy-two miRNAs were upregulated and thirty-five miRNAs were downregulated after osteogenic induction. The results of Gene Ontology analysis and pathway analysis demonstrated that the target genes of differentially expressed exosomal miRNAs participate in the regulation of a variety of biological processes, such as catalytic activity, protein binding, metabolic processes, cell development, and differentiation, and are enriched in osteogenic differentiation-related pathways, such as MAPK signaling, AMPK signaling, and insulin signaling pathways. Our results reveal for the first time that the exosomal miRNAs derived from osteogenic differentiated PDLSCs may promote the osteogenic differentiation of BMSCs, which provides a basis for further research on the regulatory function of exosomal miRNA of PDLSCs during osteogenesis.

The effect of a novel glycolysis-related gene signature on progression, prognosis and immune microenvironment of renal cell carcinoma

Background

Glycolysis is a central metabolic pathway for tumor cells. However, the potential roles of glycolysis-related genes in renal cell carcinoma (RCC) have not been investigated.

Methods

Seven glycolysis-related gene sets were selected from MSigDB and were analyzed through GSEA. Using TCGA database, the glycolysis-related gene signature was constructed. Prognostic analyses were based on the Kaplan–Meier method. The cBioPortal database was employed to perform the mutation analyses. The CIBERSORT algorithm and TIMER database were used to determine the immunological effect of glycolytic gene signature. The expressions in protein level of eight glycolytic risk genes were determined by HPA database. Finally, qPCR, MTT and Transwell invasion assays were conducted to validate the roles of core glycolytic risk genes (CD44, PLOD1 and PLOD2) in RCC.

Results

Four glycolysis-related gene sets were significantly enriched in RCC samples. The glycolytic risk signature was constructed (including CD44, PLOD2, KIF20A, IDUA, PLOD1, HMMR, DEPDC1 and ANKZF1) and identified as an independent RCC prognostic factor (HR = 1.204). Moreover, genetic alterations of glycolytic risk genes were uncommon in RCC (10.5%) and glycolytic risk signature can partially affect immune microenvironment of RCC. Six glycolytic risk genes (except for IDUA and HMMR) were over-expression in A498 and 786-O renal cancer cells through qPCR test. MTT and Transwell assays revealed that silencing of CD44, PLOD1 and PLOD2 suppressed the proliferation and invasion of renal cancer cells.

Conclusions

The glycolysis-related risk signature is closely associated with RCC prognosis, progression and immune microenvironment. CD44, PLOD1 and PLOD2 may serve as RCC oncogenes.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12885-020-07702-7.

MiR-122-5p and miR-326-3p promote cadmium-induced NRK-52E cell apoptosis by downregulating PLD1

Cadmium is a toxic heavy metal distributed broadly in the environment and manufactory industry. Long-term exposure to cadmium, considered as a risk for kidney injury, leads to chronic kidney disease eventually. Phospholipase D1 (PLD1) promotes cell proliferation and inhibits apoptosis, and might be involved in cadmium-induced kidney injury. In this study, we used miRNA microarray assays and bioinformatics analysis to identify miRNAs, which may regulate PLD1 expression and exert an impact on cadmium-induced kidney injury. MiR-122-5p and miR-326-3p，selected as candidates, were explored for their regulatory functions in kidney injury, using NRK-52E cells. Both of these two miRNAs exhibited higher expression in kidneys of SD rats after exposure to cadmium for 6 weeks. Cadmium treatment also increased miR-122-5p and miR-326-3p and decreased PLD1 in NRK-52E cells. Both of miR-122-5p and miR-326-3p could downregulate PLD1 expression through targeting its 3'UTR and enhance cadmium-induced apoptosis, while inhibiting either of these two miRNAs could reverse such effects. In conclusion, our results suggest that miR-122-5p and miR-326-3p might enhance cadmium-induced NRK-52E cell apoptosis through downregulating PLD1 expression.

miR-101-3p and miR-199b-5p promote cell apoptosis in oral cancer by targeting BICC1

microRNAs (miRNAs) are involved in the carcinogenesis and progression of oral cancer. In this research, we aimed to identify the DE_miRNAs in oral cancer and the related molecular mechanisms. Using the GEO2R online tool, we identified 19 DE_miRNAs from the GSE115117 dataset and 3343 the DEGs from GSE74530 dataset. GO enrichment analysis of DE_miRNAs were performed using FunRich online analysis. Venn diagrams of the overlapping genes regulated by miR-204-5p, miR-199b-5p, and miR-101-3p were constructed using Draw Venn Diagram, FunRich, miRDB, TargetScan and GSE74530 databases. Cytoscape was used to construct a miRNAs-mRNAs network. RT-PCR and western blotting showed downregulation of miR-199b-5p and miR-101-3p, and upregulation of BICC1 in oral cancer cell lines and tissues. Spearman correlation analysis further demonstrated a positive correlation between miR-101-3p and miR-199b-5p levels and that miR-199b-5p and miR-101-3p were negatively correlated with BICC1 mRNA levels. miR-199b-5p and BICC1 were significantly related to survival rate of patients with oral cancer. Upregulation of miR-199b-5p and miR-101-3p inhibited the viability and promoted the apoptosis in TSCCA and SCC-9 cells, as shown by the CCK8 assay and flow cytometry analysis, respectively. Inhibition of BICC1 reduced viability and promoted apoptosis in TSCCA cells. Additionally, the relationship between BICC1 and both miR-101-3p and miR-199b-5p was assessed by a luciferase reporter assay. The effects of miR-101-3p and miR-199b-5p upregulation on the promotion of cell apoptosis and the inhibition of tumor growth were reversed by overexpression of BICC1. In conclusion, the increased levels of miR-199b-5p and miR-101-3p enhanced apoptosis and suppressed cell viability in oral cancer by suppressing BICC1 expression.

Transcription Factor E2F1 Aggravates Neurological Injury in Ischemic Stroke via microRNA-122-Targeted Sprouty2

BACKGROUND

It has been documented that microRNAs (miRs) assume a pivotal role in the development of ischemic stroke (IS). However, it remains poorly identified about the role of miR-122 in IS. Herein, this study was intended to explore the mechanism of E2F1-orchestrated miR-122 in IS.

PATIENTS AND METHODS

E2F1, miR-122, and SPRY2 expression in serum from patients with IS and oxygen-glucose deprivation (OGD)-treated N2a cells was detected by RT-qPCR. After gain- and loss-of-function approaches in OGD-induced N2a cells, GAFP staining, flow cytometry, and Western blot analysis were adopted to assess neuronal viability, cell cycle and apoptosis, and expression of apoptosis- and autophagy-related proteins, respectively. Meanwhile, mice with IS were induced, in which E2F1, miR-122, and SPRY2 were overexpressed, followed by evaluation of neurological deficit and cerebral infarction area. The MAPK pathway activity in tissues of mice and cells was determined.

RESULTS

miR-122 was down-regulated, and E2F1 and SPRY2 were up-regulated in IS patients and OGD-induced N2a cells. E2F1 inhibited miR-122 transcription, while miR-122 targeted SPRY2. Overexpression (OE) of miR-122 or down-regulation of E2F1 or SPRY2 increased viability, but decreased apoptosis, cell cycle arrest, and autophagy in OGD-induced N2a cells. In IS mice, the neurological deficit score and cerebral infarction area were elevated, which was aggravated by up-regulating E2F1 or SPRY2 but attenuated by overexpressing miR-122. E2F1/miR-122/SPRY2 axis mediated the MAPK pathway in vivo and in vitro.

CONCLUSION

Collectively, E2F1 reduced miR-122 transcription to up-regulate SPRY2, which inactivated MAPK pathway and promoted neurological deficit in IS.